per the federal facility agreement for iowa army

Per the Federal Facility Agreement for Iowa Army Ammunition Plant, Article X.B.1, the attached document is the final version of the submitted document.

Prepared for:

I':'P'I':'1~

March 1998

ECOLOGICAL RISKASSESSMENT ADDENDUM 1

IOWA ARMY AMMUNITION PLANT (IAAAP)Middletown,lbwa

Volume IDRAFT FINAL REPORT

U.S. ARMY CORPS OF ENGINEERSOmaha District

ECOLOGICAL RISK ASSESSMENT ADDENDUMIOWA ARMY AMMUNITION PLANT

Table of Contents

1.0 EXECUTIVE SUMMARy 1-11.1 Purpose and Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1-11.2 Problem Formulation 1-21.3 Ecological Risks at lAAAP .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1-4

2.0 INTRODUCTION 2-12.1 Project Authorization And Purpose 2-12.2 Previous Studies 2-12.3 Scope of the Ecological Risk Assessment Addendum 2-2

3.0 PROBLEM FORMULATION 3-13.1 Ecological Site Description 3-13.2 Geology 3-53.3 Hydrogeology 3-63.4 Surface Water 3-83.5 Chemical Data Collection and Review 3-93.6 Selection of Preliminary COECs 3-93.7 Selection of Key Receptors 3-103.8 Ecological Assessment and Measurement Endpoints 3-133.9 Conceptual Site Model '" " .. 3-153.10 Field Methods and Materials '" 3-15

4.0 BRUSH CREEK WATERSHED 4-14.1 Watershed Description 4-14.2 Results ofField Sampling 4-134.3 Risk Characterization 4-22

5.0 LONG CREEK WATERSHED 5-15.1 Watershed Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5-15.2 Results ofField Sampling 5-105.3 Risk Characterization .. " " '" '" .. 5-18

6.0 SPRING CREEK WATERSHED 6-16.1 Watershed Description 6-16.2 Results ofField Sampling 6-96.3 Risk Characterization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-17

7.0 SKUNK RIVER WATERSHED 7-17.1 Watershed Description 7-17.2 Results ofField Sampling 7-7

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Final)

March 23, 1998Page i

7.3 Risk Characterization. " '" '" 7-7

8.0 BASEWIDE RISKS 8-18.1 Project Remediation Goals 8-18.2 Basewide Receptors 8-68.3 Conclusions 8-8

9.0 REFERENCES 9-1

APPENDICESA. Screening and Preliminary Identification of COECsB. Estimation of Exposure Point ConcentrationsC. Terrestrial Exposure and Risk EstimationD. Laboratory ReportsE. Field LogsF. Benthic Macroinvertebrates


March 23. 1998Page ii

AECARDLBCFx

BHCBTAGBTEXCBOD5COECCPOMCWPDA/DFDBHDDDDDEDDTDNRDNTDODODEDAExEMREPAEPTERAERAAEWIFDAHBIHEPHIHMXHQIAAAPIDAKow

LAPLCx

LOAELMDLNOAELNOEL

LIST OF ABBREVIATIONS AND ACRONYMS

Army Environmental CenterApplied Research Development LaboratoryBioconcentration Factor, for x=a (aquatic animals), for x=t (terrestrialherbivores)HexacWorocyclohexaneBiological and Technical Advisory GroupBenzene, Toluene, Ethylbenzene, XylenesCarboneous Biochemical Oxygen Demand (5 day)Chemical of Ecological ConcernCoarse Particulate Organic MatterContaminated Waste ProcessorDemolition Area/Deactivation FurnaceDiameter at Breast HeightDicWorodiphenoldichloroethaneDicWorodiphenolcWoroethaneDichlorodiphenoltrichloroethaneDepartment ofNatural ResourcesDinitrotolueneDissolved OxygenDepartment of DefenseExplosive Disposal AreaExposure from x=f (food), x=w (water), x=s (ingestion)Exposure Modification RateEnvironmental Protection AgencyEphemeroptera, Plecoptera, TricopteraEcological Risk AssessmentEcological Risk Assessment AddendumExplosive Waste IncineratorFood and Drug AdministrationHilsenhoffBiotic IndexHabitat Evaluation ProcedureHazard IndexOctahydro-l,3 ,5,7-tetranitro-l ,3,5,7-tetrazocineHazard QuotientIowa Army Ammunition PlantInert Disposal AreaOctonol-Water Partition CoeffientLoading, Assembly, and PackingLethal Concentration for X Percentage of PopulationLowest Observed Adverse Affect LevelMethod Detection LimitNo Observed Adverse Effects LevelNo Observed Effect Level


March 23, 1998Page iii

NPDESPCBPNAPRGRAGSRBPRIRDXRTVSCVSQISRISVOCTCETNBTNTUCLUSACEUSEPAUSGSVOCWQAPPWQCWWTPYSI

National Pollutant Discharge Elimination SystemPolychlorinated BiphenylPolynuclear Aromatic HydrocarbonProject Remediation GoalsRisk Assessment Guidance for SuperfundRapid Bioassessment ProtocolRemedial InvestigationHexahydro-I ,3,5-trinitro-1 ,3,5-triazineReference Toxicity ValueSecondary Chronic ValueSite Quality IndexSupplemetal Remedial InvestigationSemi-Volatile Organic CompoundTrichloroethyleneTrinitrobenzeneTrinitrotolueneUpper Confidence LimitU. S. Army Corps of Engineers, Omaha DistrictU. S. Environmental Protection AgencyU.S. Geological SurveyVolatile Organic CompoundCombined Work/Quality Assurance Project PlanWater Quality CriteriaWastewater Treatment PlantYellow Springs Instrument


March 23. 1998Page iv

FC!J0;/CiLl J<,~i: IIJteiS~J,J Arid(I1c1/)~

11!'(~ frrf1.0 EXECUTIVE SUMMARY

1.1 Purpose and Scope

The purpose of this study is to complete and prepare an addendum to a previous ecological risk assessment

at the Iowa Army Ammunition Plant (IAAAP), Middletown, Iowa. The ecological risk assessment addendum

(ERAA) will complement ongoing soil and groundwater remediation efforts at this site. Historical and

ongoing contamination, as well as loss of habitat due to current land use practices are to be considered as

ecological stressors. The following tasks are addressed within the framework of this study:

• Identification of ecological receptors of concern, including the identification of governmental

listed endangered or threatened species.

• Identification of critical/sensitive habitats, if any, based on the presence of

threatened/endangered/endemic species, fragile ecosystems, or breeding/spawning

considerations.

• Identification of contaminants of ecological concern (COEC).

• Identification, analysis and discussion of ecotoxicity values for the receptors of concern.

• Incorporation into the ERAA, as appropriate, of ecological information presented in the report,

"Uptake of Explosives from Contaminated Soil by Existing Vegetation at the Iowa Army

Ammunition Plant", AEC, February 1995.

• Identification, investigation and discussion of the recommendations in the previous baseline

ERA.

• Collect physical and chemical data determined essential to completion ofthis effort.

• Preparation ofa written Risk Characterization for IAAAP, following the requirements presented

in Section 3.4 of EM 200-1-4: Risk Assessment Handbook, Volume II: Environmental

Evaluation; USACE 1996 as well as the guidance of the USEPA RAGS (1997).


March 23, 1998Page '·1

1.2 Problem Formulation

1.2.1 Site Description

The IAAAP is located in the Dissected Till Plain section of the Central Lowland Province of the Southern

Iowa Drift Plain Region. Surface topography is characterized by flat to gently rolling uplands dissected by

entrenched streams and rivers. The IAAAP can be considered largely as four watersheds; from east to west,

they are Spring Creek, Brush Creek, Long Creek and Skunk River. Approximately a third of the IAAAP

property is occupied by active or formerly active production or storage facilities. The remaining land is

approximately evenly divided between leased agricultural acreage and woodlands.

No federal-listed endangered species are known to occur at the Plant. However, the bald eagle, listed as

threatened, has been recorded to feed at the site. The Indiana bat may summer on the property, and surveys

to determine its presence are planned by IAAAP for 1998. Six state-listed threatened plants and one

threatened fish are known to occur on the site.

Stream flow within the IAAAP comprises three principal elements: surface runoff; groundwater inflow; and

discharges under NPDES (National Pollutant Discharge Elimination System permits). Groundwater

contributions to the streams appear to increase significantly from upstream to downstream across the IAAAP.

This may result from increasing hydraulic heads adjacent to the creek as it becomes more deeply incised.

1.2.2 Selection of Chemicals of Ecological Concern (COECs)

COECs were identified on a watershed basis. Data representing groundwater and soils deeper than 24 inches

were eliminated from consideration as these generally do not present a significant exposure pathway to

ecological receptors. Data also eliminated from further consideration included non-detections, probable lab

contaminants and essential nutrients. Data on contaminants remaining after these eliminations were

subjected to a frequency analysis and compared to toxicity benchmarks or thresholds. This final step

eliminated contaminants that were below threshold levels or were limited in their distribution.

1.2.3 Ecological Receptors

Migration routes for contaminants at the IAAAP are primarily waterborne. Upland soil loss and sediment

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Fina/)

March 23, 1998Page 1-2

transport, NPDES discharges and groundwater discharge to surface waters are the primary mechanisms for

contaminant transport at the IAAAP. All transport is likely to be concentrated by or to follow existing

surface drainage patterns. Sediment transport and groundwater movement would likely

concentrate/discharge into the riverine flood plains adjacent to the major stream channels traversing the plant

property. Soils and biota inhabiting flood plain areas are indicative of the significance of all possible

contamination exposure pathways and were selected for this ERAA.

Small burrowing mammals inhabiting flood plain forests on the IAAAP were identified as key receptors for

study. The most common small mammals in IAAAP flood plains are white-footed mouse (Peromyscus

leucopus), meadow vole (Microtus pennsylvanicus), and short-tailed shrew (Blarina brevicauda). The

advantage in selecting mice or shrews as study receptors is the limited home ranges ofthese small mammals;

larger flood plain inhabitants such as raccoon (Procyon lotor) have much greater ranges and contaminant

body burdens may not directly reflect the trapping location.

The assessment endpoints for the terrestrial ecological risk assessment are the health of the vascular plant

community and the viability ofwildlife populations. To assess the health of the vascular plant communities

potentially affected by chemical contamination, the community quality index developed in a study ofIAAAP

flora and fauna by Horton et al. (1996), was the measurement endpoint. Additionally, because of federal

listing as a threatened species, the viability of bald eagle (Haliaeetus leucocephalus) population was assessed

using reproductive success as the assessment endpoint. As high trophic level consumers are exposed

primarily via their diet, the measurement endpoint is body burdens of COECs in prey. Utilizing the body

burdens of contaminants in small mammals and fish, the intake of those contaminants by bald eagle

individuals were projected and evaluated using literature-based benchmarks for toxicological effects.

Selection ofkey aquatic receptors focuses on two levels ofbiological organization: an individual fish species,

and the benthic community. Because of its listing as a threatened species by the State of Iowa, the

orangethroat darter (Etheostoma spectabile) was selected as a key receptor. However, because of the

orangethroat darter's threatened status, the fantail darter (E.jlabellare) and Johnny darter (E. nigrum) were

utilized as surrogates for analysis of contaminant residues. Both of these darters have similar food habits

to the orangethroat. The benthic community was selected as a key receptor because of its importance in

aquatic food chains and industry-wide acceptance as an indicator of ecological health.

Aquatic assessment endpoints are the viability of individuals ofthe state-listed threatened orangethroat darter


March 23. 7998Page 1-3

and the health of the benthic macroinvertebrate community. The risk measurement endpoint for the

orangethroat darter population was the levels ofCOECs bioaccumulated in individuals of fantail and Johnny

darters. The significance of these levels was evaluated using literature-based benchmarks for toxicological

effects. The measurement endpoint for the health of the aquatic benthic community was assessed using the

Rapid Bioassessment Protocol III developed by the USEPA (Plafkin, et al. 1989).

1.3 Ecological Risks at IAAAP

1.3.1 Watershed-Based Risks

The risk posed by past and ongoing operations at IAAAP were assessed separately for each of the four

watersheds using the above described approach. Table I-I is a summary table of the ERAA findings. In

general, aquatic systems are exposed to concentrations of some metals that may be affecting orangethroat

darters in Spring and Brush Creeks. Good numbers of this threatened species were found in these streams

during our field investigations, and individuals that we examined did not show signs of stress as indicated

by DELTs (deformities, eroded fins, lesions, or tumors).

The benthic community was appraised as being impaired to slightly impaired. The benthos in the streams

are generally more diverse and balanced than streams in completely agricultural watersheds of eastern Iowa.

Aquatic invertebrates are known to become moderately tolerant of metals, and the benthos measurement

endpoints may not reflect risks from metals seen in the darter viability risk assessment.

Risks to terrestrial ecosystems were assessed using both measurement and modeling procedures. The forest

community structure endpoint shows the adverse effects of ongoing land use and management practices.

Reduced forest tract size is likely impacting forest quality. Forest ecology principals demonstrate that

reducing tract size, while increasing gaps or "edge" habitats, alters microclimate in the forest that affects

species diversity, dominance and abundance. Inside the forest tract of reduced size, wind speeds increase,

mean temperature increases, humidities decrease, and light penetration increases. All these factors reduce

forest quality, and at IAAAP, are more likely affecting forest community structure than industrial

contamination.



Table 1-1. Summary of ERAA Findings

Watershed Benthic Community Darter Viability Forest Community Small Mammal Viability Bald EagleStructure Structure Viability

Brush Creek 5 sites = unimpaired Silver HQ ~ 14 Impacted by reduced forest Silver HQ = 0.4 to 1.4 FONSI4 sites ~ slightly impaired Thallium HQ ~ 1.7 plot size. Dibenzofuran HQ = 1.2

Lead HQ= l.lContaminants ~ FONSI

-- -- -- ------ ----- -'---- - ----- ---- - ------- ------ --- - - ---- .._- ----_. --- --

Uncertainty = low Uncertainty ~ high Uncertainty ~ moderate to Uncertainty ~ moderate to Uncertainty ~

to moderate low high moderate to low

Long Creek 2 sites ~ unimpaired FONSI FONSI FONSI FONSI2 sites ~ slightly impaired

1---..---,--------------- -"-'---- -_...._- -- .

Uncertainty = low Uncertainty = high Uncertainty ~ moderate to Uncertainty ~ moderate to Uncertainty =low high moderate to low

Spring Creek 2 sites = unimpaired Barium HQ ~ 27 Impacted by reduced forest FONSI FONSI3 sites ~ slightly impaired Copper HQ = 3.5 plot size.

Lead HQ ~ 1.3Contaminants ~ FONSI

-_ .._- - ------ --- ----- ---- -- ---- ------ . - --- -------- --- -- --- ------------_... _---_.",- ._-- -------

Uncertainty = low Uncertainty ~ high Uncertainty ~ moderate to Uncertainty = moderate to Uncertainty ~

low high moderate to low

Skunk River I sites ~ unimpaired N/A Contaminants ~ FONSI FONSI FONSItributaries I sites = slightly impaired

-- -- _..- - - --- -- --- . --- --- - . .. ---- - . ---- - .. _. ---- ---

Uncertainty = low to moderate N/A Uncertainty ~ moderate to Uncertainty = high Uncertainty ~

low moderate

FONSIN/A

Finding of No Significant ImpactNot Applicable



The viability of small mammal populations does not appear to be at significant risk in any watershed. Hazard

quotients (HQ) exceeding unity are limited to silver in soils near the wastewater treatment plant (WWTP)

on Brush Creek. Dibenofuran may present a slight hazard to small mammal populations in the Brush Creek

watershed, but additional analytical data would be needed to confirm the significance of this COEC there.

Bald eagle populations do not appear to be at risk in the lAAAP.

1.3.2 Basewide Risks

A watershed-based ERA such as presented herein may not address risk for wide-ranging species, so an

additional risk assessment was performed using a modifed conceptual site model. To evaluate the potential

for risk to a wide-ranging predatory species that feeds solely on the lAAAP, we estimated risk to red-tailed

hawk (Buteo jamaicensis). The red-tailed hawk is the most common Buteo sp. in the US and it does occur

on the lAAAP property. We estimated risk to this raptor, under the following assumptions:

• Soil COEC concentrations in Brush Creek watershed represent exposure point

concentrations. COEC concentrations in Brush Creek are generally the highest

among the four watersheds.

• Only biomagnif'ying COECs represent a significant risk to predatory biota.

• All feeding by the hawk occurs in the Brush Creek watershed

Under these conservative assumptions, several biomagnif'ying COECs have hazard quotients exceeding unity

and represent potential effects greater than the NOAEL. COECS presenting possible risks include

dibenzofuran, DDT metabolites, and chlordane. None of these contaminants are due to munitions

manufacturing and all are based on very few measurements relative to the the database for explosives and

metals. While they may be due to historic application of agrochemicals by farmers leasing lands on the

lAAAP, DDT and its metabolites, and chlordane are no longer licensed for agricultural use. The chlordane

exposure point concentration is derived from a single measurement event from the Brush Creek watershed

at the Pesticide Pit in November, 1992, and is not representative of general basewide conditions. The

uncertainty of the HQs for dibenzofuran, DDT metabolites, and chlordane is high for all. Additionally the

HQs are likely overestimates due to the small size of the database, the use of the most contaminated

watershed (Brush Creek) to represent the total feeding area of red-tailed hawks, and the use of NOAEL

criteria for hazard estimation.

lows Army Ammunition PlantEcological Risk Assessment Addendum (Draft FinalJ


1.3.3 Project Remediation Goals (PRGs)

The lAAAP PROs for soil and water are based on protection ofhuman health (Harza 1997a). Screening level

review of the human health based soil PROs at IAAAP indicates that remediated soil sites may continue to

pose risk to ecological receptors. To address this contingency, we modified the risk models developed for

watershed-based risk assessment to further assess the ability of the soil PROs to protect ecological receptors

at the IAAAP. Pathways and receptors of concern specifically were:

• Small mammals colonizing remediated terrestrial upland habitats

• Myotis bats feeding over remediation wetlands on recently hatched aquatic insects.

Both exposure scenarios assumed that all feeding occurs in habitats contaminated at the soil PRO levels.

This assessment indicates that adverse effects to white-footed mice (or comparable upland species) may

occur on remediated lands due to residual antimony, arsenic, cadmium, chromium VI, thallium, TNB or

HMX.

Another scenario involved residual contamination in sediment of remediation wetlands at the soil PRO levels.

Hazard quotients exceeding unity may present adverse effects to Myotis bats. COECs that are shown in this

model to present a significant possibility of adversely affecting bats are antimony, cadmium, chromium VI,

thallium, benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, dibenzo(a,b)anthracene, and PCB.

The PROs for explosives, which are the principal driver to remediation of most contaminated soils, are

sufficient to protect bats and small upland mammals.

NOAEL values were used in these assessments of soil PROs; consequently they are conservative estimates.

Lastly, we compared groundwater PROs to available NOAEL criteria for protection of orangethroat darters.

Chemicals found in groundwater at concentrations exceeding the NOAEL criteria do not generally pose a

hazard to ecological receptors. The exception to this occurs when groundwater discharges to surface streams

or wetlands. In these cases, if the discharge is in sufficient quantities, and the NOAEL concentrations are

exceeded after dilutional effects, ecological risks may begin to be manifested and the threatened darter

population be stressed. PROs exceed NOAEL concentrations for barium, iron, and manganese, but so do

natural background concentrations in surface water at IAAAP. PROs also exceed NOAEL concentrations

for I, I, I-trichloroethane and bis(2-ethylhexyl)phthalate, but not for any explosives for which we developed

10 W8 Army Ammunition PlantEcological Risk Assessment Addendum (Draft Fina!J


NOAELs. As is the case for soils, the PROs for explosives are the principal driver to remediation of most

contaminated groundwater, and those cleanup objectives are sufficient to protect darters.

10 wa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Final)

March 23. 1998Page 1·8

2.0 INTRODUCTION

2.1 Project Authorization And Purpose

This study was authorized by the U. S. Anny Corps of Engineers, Omaha District under delivery order

number 16, contract number DACW45-94-D-0044, to Harza Environmental Services, Inc., of Chicago,

Illinois, dated March 28, 1997.

The purpose of the study is to complete and prepare an addendum to a previous ecological risk assessment

at the Iowa Anny Ammunition Plant (IAAAP), Middletown, Iowa. The ecological risk assessment addendum

(ERAA) will complement ongoing groundwater remediation efforts at this site. Ongoing and anticipated

contamination, as well as loss ofhabitat due to current land use practices are to be considered as ecological

stressors.

2.2 Previous Studies

For this ERAA, the primary background document is the Revised Draft Final Remedial Investigation Risk

Assessment (Volume II of II) prepared for the U.S. Anny Environmental Center by JAYCOR (McLean,

VA) and ICAIR Life Systems, Inc. (Cleveland, OH) dated May 21, 1996. This document reported a

basewide ecological risk assessment, and contained several recommendations regarding unresolved issues.

The JAYCOR ERA concluded significant risks may exist at the IAAAP to several ecological receptors, but

that uncertainty was high for most aspects of their assessment. The literature screening approach utilized

by JAYCOR suggested to them that phytotoxicity due to metals exposure may pose a threat basewide.

However, they expected that the degree of toxicity is subtle in nature given the general lack of signs of

chemical stress observed during the vegetation survey. They also indicated that most soils pose a toxicity

threat to soil invertebrates. A simplistic model suggested that herbivorous mammals could be at risk due to

exposure to metals, nitrite and explosives.

JAYCOR also examined aquatic ecosystems on the IAAAP in a screening analysis comparing sediment

maximum concentrations to sediment quality criteria established for five non-ionic organic chemicals or to

apparent effects thresholds for metallic and other organic chemicals. The order of expected adverse impact

due to chemical exposure for each of the streams on the site is:



Brush Creek> Long Creek> Skunk River> Spring Creek

JAYCOR indicated that food chain transfer for explosives was not expected to be significant due to relatively

low bioconcentration factors and high degree ofexpected metabolism. However, certain metals have been

shown to bioaccumulate and may pose a threat to terrestrial and aquatic organisms.

JAYCOR recommended additional ERA studies based on their screening evaluations:

• Sediment toxicity testing in some areas.

• Plant toxicity tests.

• Earth worm toxicity.

• Tissue samples ofterrestrial vegetation, earthworms, small mammals, benthic invertebrates and

fish from background locations and locations where toxicity is indicated to determine if

contaminants are bioavailable to potentially exposed organisms, to evaluate bioaccumulation

potential, and toxicity threats to organisms at higher trophic levels.

During their review of this document, the U.S. Environmental Protection Agency (EPA) determined that

additional data collection and analysis of certain factors were needed. Also, following the issuance of the

JAYCOR document, a study produced by the Army Environmental Center (AEC) entitled "Uptake of

Explosives from Contaminated Soil by Existing Vegetation at the Iowa Army Ammunition Plant," (2/95) was

issued. Based on the findings of the EPA and the AEC study, a Scope of Services for additional data

collection was issued to determine the impacts of the existing/anticipated chemical data on the IAAAP

ecosystem, with emphasis on sensitive receptors and habitat. These services were to be performed as an

addendum to the original ERA.

2.3 Scope of the Ecological Risk Assessment Addendum

The intent of this study is to conduct an ERAA for the IAAAP watersheds to address gaps in the original

Baseline Risk Assessment (ecological risks), following applicable guidance, specifically Volumes I and II

of the Risk Assessment Guidance for Superfund (RAGS).



The biotic pathways of concern are the basewide groundwater, surface water, soils and sediments. The

following tasks are addressed within the framework of this study:

• Identification of ecological receptors of concern, including the identification of state and

federally listed endangered or threatened species.

• Identification of critical/sensitive habitats, if any, based on the presence of

threatened/endangered/endemic species, fragile ecosystems, or breeding/spawning

considerations.

• Identification of contaminants of ecological concern (COEC).

• Identification, analysis and discussion of ecotoxicity values for the receptors of concern.

• Incorporation into the ERAA, as appropriate, ofecological information presented in the report,

"Uptake of Explosives from Contaminated Soil by Existing Vegetation at the Iowa Army

Ammunition Plant" AEC, February 1995.

• Identification, investigation and discussion of the recommendations in the previous baseline

ERA.

• Collect any physical/chemical data determined essential to completion of this effort.

• Preparation ofa written Risk Characterization for IAAAP, following the requirements presented

in Section 3.4 of EM 200-1-4: Risk Assessment Handbook, Volume II: Environmental

Evaluation; USACE 1996.



3.0 PROBLEM FORMULATION

3.1 Ecological Site Description

The IAAAP is located in the Dissected Till Plain section of the Central Lowland Province of the Southern

Iowa Drift Plain Region. Surface topography is characterized by flat to gently rolling uplands dissected by

entrenched streams and rivers. Approximately a third of the IAAAP property is occupied by active or

formerly active production or storage facilities. The remaining land is approximately evenly divided

between leased agricultural acreage and woodlands.

The IAAAP is drained by five water courses. Little Flint Creek drains a small area in the north and is not a

part of this study. The rest ofthe plant is drained by, west to east, the Skunk River, Long Creek, Brush Creek

and Spring Creek. Long Creek is a tributary to the Skunk River and includes the George M. Mathes Dam

and reservoir within the IAAAP. Other, minor tributaries to Skunk River drain the extreme southwest part

of the installation. Brush and Spring Creeks traverse the central and eastern portions of the installation and

are tributary to the Mississippi River about ten miles east. Long, Brush and Spring Creek valleys are

relatively shallow in the north part of the IAAAP, deepening to the south before exiting the installation at

a steep bluff bounding the Skunk River Valley.

Land use/land cover types at IAAAP include forests, water, bottom land forests and other wetlands, prairies,

industrial and ruderal areas, residential and agriculture. Forest types can be separated into flood plain and

upland forests, with the former predominating. Flood plain forests are dominated by black willow, honey

locust, American and slippery elms, cottonwood, and sycamore, with an understory consisting largely of

poison ivy, poison oak, grape, Virginia creeper, gooseberry, blackberry, multiflora rose, nettles, carrots,

sedges and mints. Upland forests at IAAAP are xeric, oak-dominated successional communities that

represent transitional stages between oak and sugar maple dominance. The overstory is dominated by red

and white oaks and shagbark and bitternut hickories. The understory is characterized by young sugar maple,

hophornbeam, and other tree and shrub species.

The other major land use/land cover types include those developed for agriculture and industrial plant

operations. Agricultural uses include the row crops corn and soy beans, and pasture for beef production.

Most pasturing takes place in munition storage yards.

Iowa Army Ammunition PlantEcologica/ Risk Assessment Addendum (Draft)

March 17, 1998/Rev. IPage 3·1

Exhibit 3-1 is a land use/land cover map of the IAAAP prepared from 1994 aerial black and white

photographs, soil survey maps, and National Wetland Inventory maps. The preliminary map was later field

checked. Land was categorized according to the following system:

Upland Forest

Bottomland Forest:

Old Field:

Wetland

Agriculture

Base Facilities

Open Water, PondlLake

Residential

Disturbed (barren)

Base Facilities/Old Field

Saplings and mature trees over 6" in diameter at breast height (DBH)forming an overhead canopy providing more than 50 percent ground coveron uplands (other than bottom land, flood plain, topography).

Saplings and mature trees over 6" DBH, hydrophytic species, forming anoverhead canopy providing more than 50 percent ground cover on bottomland (flood plain) topography.

Areas cleared of woody vegetation in the past and allowed to revegetatewith primarily herbaceous grasses, herbs, woody shrubs, and may have atree canopy providing less than 50 percent ground cover. Such areas maybe used as pasture for cattle, but not for crop production and not maintainedas landscaped lawn.

Areas exhibiting hydrophytic conditions of emergent wetland vegetationand bottomland (flood plain) and/or depression-like topography.

Areas exhibiting recent or active evidence of crop production, eitherexistence of crops, recently plowed, or fallow.

Includes areas occupied by structures, railways, and paved and unpavedroads and parking lots.

Lacustrine habitats. Includes permanent water bodies.

Single or multi-family residential homes and apartments and surroundinglandscaped lawn areas.

Lands recently cleared of all vegetation and with no indication ofagricultural or other use.

Grassed areas (mowed and unmowed) surrounding base facilities, normallynot used as pasture for cattle.

Using this land use/land cover system, each of the four watersheds are characterized below. The totals for

each land use type may be greater than the sum ofthe four watersheds as it includes the small area tributary

to the Flint River.

Iowa Army Ammunition PlantEcological Risk Assessment Addendum fDraft Final)


Table 3-1. Present Land UselLand Cover at the IAAAP (Acres)

Brush Creek Skunk River Long Creek Spring Creek Totals

Upland Forest 563 1,441 2,693 1,386 6,083

Flood Plain Forest 221 72 483 296 1,073

Old Field 981 258 1,073 590 2,901

Other Wetlands 7 0 2 27 35

Agriculture 1,909 412 2,487 1,100 5,908

Base Facilities 681 115 236 58 1,090

Open Water, PondILake 15 5 128 7 155

Residential 0 0 69 0 69

Disturbed (barren) 107 4 0 46 157

Base Facilities/Old Fields 529 192 497 384 1,601

Totals 5,014 2,499 7,669 3,892 19,074

There is an abundant and diverse fauna at IAAAP. This is due not only to the diverse habitat mosaic

provided by the upland and lowland forests, stream, wetlands, prairies and agricultural areas, but also to the

relative protection from human disturbance outside of plant facilities.

No federal-listed endangered species are known to reside on the lAAAP property. However, the bald eagle

(Haliaeetus leucocephalus), listed as threatened, has been recorded to feed at the site. Three other birds on

the federal threatened or endangered species list range into Iowa: peregrine falcon (Falco peregrinus), piping

plover (Charadrius melodus) and least tern (Sterna antillarum). Peregrine falcon is listed as endangered but

is being considered for relisting as threatened; the DDT ban and the success of artificial hacking programs

has led to a resurgence of its numbers nationwide. Peregrines likely migrate through Des Moines County

and breeding pairs are known in other parts of the state. The numbers of piping plover are perilously low

and the bird is listed as an endangered species. Plovers breed along shores of rivers and lakes in the Northern

Great Plains and use wide, flat open sandy beaches with very little grass or other vegetation. Nesting

territories may include sandy areas adjacent to small creeks or wetlands. The least tern is listed as threatened

because of disturbance of its nesting habitats along riverine and lacustrine sand and gravel bars. It breeds

and feeds in isolated areas along the Mississippi River, but suitable habitat is not on the IAAAP property.

While not recorded at IAAAP, Indiana bats (Myotis sodalis) may summer on the property. Surveys to

determine its presence are planned by IAAAP for 1998. Depending on this species-specific wildlife study's

findings regarding the presence or absence ofIndiana bats, this risk assessment may need to be revised to

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Oraft Final)


include this species as a receptor. It has not been addressed as a receptor in this ERAA because of the

inability of prior sampling efforts (Horton et al. 1996) to find this bat on the property.

Aquatic vertebrates on the federal list of protected species ranging into Iowa include pallid sturgeon

(Scaphirhynchus albus) and Topeka shiner (Notropis topeka). The pallid sturgeon is listed as endangered.

It inhabits large rivers like the Mississippi and Ohio and has not been found at IAAAP. The Topeka shiner

is proposed by the U.S. Fish and Wildlife Service for listing as endangered. In Iowa, it receives no special

recognition. The Topeka shiner is adapted to prairie streams with high quality water and is associated with

seeps or springs. It has not been found on IAAAP either.

Two invertebrates and five plants also range into Iowa that are on the federal list: Higgins' eye pearly mussel

(Lampsilis higginsi), Iowa Pleistocene snail (Discus macclintocki), Eastern prairie fringed orchid

(Platantehera leucophaea), Mead's milkweed (Asclepias meadil), Northern wild monkshood (Aconitum

noveboracense), Prairie bush-clover (Lespedeza leptostachya) and Western prairie fringed orchid

(Platanthera praeclara). None of these organisms have been found on the property.

State listed endangered, threatened, and special concern species found by Horton et al. (1996) on the site are

tabulated below. The listing of a species by a state as threatened or endangered does not necessarily

constitute an affirmation of that species' imminent or threatened loss. In general, state listing implies that

a species is rare, and this is frequently due to limitations of biogeography: the species is on the edge of its

natural range. For example, orangethroat darter (Etheostoma spectabile) is quite common in Missouri, but

the northerly limit of its range is Des Moines County, and as such, it is considered by the Iowa DNR as

threatened in that state.

Table 3-2. State Protected Species Known to Occur on the IAAAP

Common name Scientific Name Status'

Plants

Viginia snakeroot AristoJochia serpentaria T

Downy wood~mint Blephilia ciliata T

Blue ash Fraxinus quadrangulata T

Sharpwing monkeyflower Mimu/us ala/us T

Ragged fringed orchid Platanthera lacera SC

IOWB Army Ammunition PlantEcological Risk Assessment Addendum (Draft Fina/)


SC special concern, T=threatened, E endangered

Table 3-2. State Protected Species Known to Occur on the IAAAP

Common name Scientific Name Status l

Slender ladies tresses Spiran/hes [acera T

False hellebore Veratrum woodi T

Animals

Orangethroat darter Etheostoma spectabile TI

A complete list of State-listed threatened or endangered species that range into Des Moines County was

requested from the Iowa Department ofNatural Resources. In response to that request, the DNR provided

the following information. Considered by the State to be endangered, but have not been found on the

IAAAP, are crawfish frog (Rana areolata), yellow mud turtle (Kinosternonjlavescens), red-shouldered

hawk (Buteo lineatus), water willow (Justicia americana), dwarf dandelion (Krigia virginica), and green

arrow arum (Peltandra virginica). The State considers the following species to be threatened, but neither

are they known to occur at IAAAP: Western sand darter (Ammocrypta clara), grass pickerel (Esox

americanus), Western worm snake (Carphophis amoenus) and yellow monkey flower (Mimulus glabratus).

3.2 Geology

The IAAAP is underlain by a sequence of unconsolidated deposits of Pleistocene age, including surficial

loess and thick glacial tills, underlain by sedimentary bedrock units. The loess deposits at the IAAAP are

fine-grained, poorly sorted materials deposited by wind action in the Wisconsin period. They overlie the

glacial drift intermittently at thicknesses up to a reported 26 feet, averaging 6 to 8 feet.

The glacial tills at the lAAAP are part of the Kellersville Till Member (Illinoisan Age) of the Glasford

Formation of southeastern Iowa. The Kellersville Till is subdivided into a subglacial or basal till and a

superglacial facies. The basal till facies is composed of firm, dense, over-consolidated till of rather uniform

texture and is distinguished by its rich illite and dolomite content. The superglacial facies is composed of

a wide variety of sediments and is highly variable in texture and density. The sediments in the superglacial

facies include reworked till, sorted fluvial and lacustrine sediments, and peat beds. The tills extend to depths

in excess of 100 feet in portions of the north half of the IAAAP, but are absent locally in deeper stream

valleys in the south and generally thinner in the northwest (JAYCOR 1996).

Iowa Army Ammunition PlantEcological Risk Assessment Addendum fOraft Final)

March 17, 1998Page 3·5

The bedrock underlying lAAAP consists ofa sequence of limestones interbedded with varying thicknesses

of shales and sandstones, ranging in age from Cambrian to Mississippian. The uppermost bedrock unit

beneath the site is associated with the Mississippian Osage Series of southeastern Iowa, composed

predominantly ofcherty carbonate rocks (limestones) interstratified with minor amounts ofshale. The Osage

series is divided into three members: the Warsaw Formation, Keokuk Limestone, and Burlington Limestone.

The Warsaw Formation consists primarily ofblue-gray calcareous shales, fragmental, fossiliferous, dolomitic

limestone, and calcarenites.

The depth to bedrock varies widely across the lAAAP. Depths in excess of 100 feet are reported locally in

the northern half of the Site, while the bedrock is exposed along the edges of the Skunk River Valley in the

southwest and near the Mathes Lake dam. In core borings completed for this study, the bedrock is described

as generally gray, hard to weathered, locally fossiliferous and vuggy limestone varying between closely

fractured and massive. Shale sequences are reported from previous borings completed by others. The upper

part of the bedrock, where cored, typically is more highly fractured than at greater depths and is somewhat

weathered, providing a more permeable zone relative to the overlying clay tills or the likely less fractured

deeper bedrock zones. However, transmissivity of the upper bedrock is suggested to be highly variable

locally.

Based on the available data, bedrock beneath the IAAAP occurs between approximate elevations 565 and

670. Bedrock is exposed along portions of the Skunk River valley bluff and within the lower reaches of

Long and Brush Creeks, as well as locally elsewhere. The bedrock surface can be characterized as generally

flat between approximate elevations 625 and 650, dissected by a buried valley feature bisecting the plant

from the west central area to the east and southeast. Thus, bedrock is at or above elevation 650 beneath the

southwest and south portions of the site and the northeast corner, but is generally below elevation 600 within

the buried valley. From northwest to southeast, the valley trends beneath Line 9, most of Line 3, the south

half of Line 2, and Yard D just east of and parallel to the present surface trace of Brush Creek. Just off-site

to the south, the bedrock surface is expected to drop rapidly toward the Skunk Valley.

3.3 Hydrogeology

The IAAAP is underlain by four principal hydrogeologic units: the glacial drift and bedrock units of

Mississippian, Devonian, and Cambro-Ordovician age. Units of interest in this study are limited to the

glacial drift and the upper portion of the Mississippian bedrock.

Iowa Army Ammunition PlantEcologics! Risk Assessment Addendum (Draft Final)


The uppennost hydrogeologic unit consists of Pleistocene age unconsolidated deposits including surficial

loess overlying glacial till. Thin fluvial deposits underlie active stream beds, but are generally less than three

feet thick and ofno significance hydrogeologically. The glacial deposits occupy the upland till terrace and

are predominantly clayey and silty glacial tills. They range up to more than 100 feet thick locally, but are

absent or very thin in portions of the southwest and south part of the site. The drift contains little free

groundwater, but cannot be considered a perched aquifer. Rather, the till acts as an aquitard, slowing

precipitation recharge ofthe underlying bedrock. Most identifiable groundwater recharge to site wells and

borings derives from thin, generally one to two foot thick or less, discontinuous and not interconnected silt

and sand seams within the clayey till. Despite a paucity of significant water-bearing strata, the drift is

saturated below shallow depths and the groundwater is in hydraulic communication with the bedrock. The

groundwater table in the drift generally occurs within ten feet of the ground surface, and often less, and

shallow groundwater flow closely parallels the ground surface. Thus, shallow groundwater flow within the

base is from topographic highs, including most of the Line and Yard areas, toward surface drainages,

particularly the larger streams such as Spring, Brush, and Long Creeks and the Skunk River. Piezometric

data from well pairs and clusters show that a significant downward vertical gradient exists within the drift,

and between the drift and the bedrock. The glacial drift aquifer is recharged directly by infiltration of

precipitation. Because ofthe downward vertical gradient, the drift aquifer also discharges downward to the

bedrock aquifer. However, this component of recharge is expected to be minor compared to lateral flow.

Available data on hydraulic properties of the drift soils indicate low penneabilities. Results of field tests by

Harza indicate penneability values ranging from I x 1<t to I x 10" cmlsec (Harza 1997a). Data reported

in the Draft Final RI Report (JAYCOR 1996) indicate laboratory penneabilities for till samples ranging from

2.4 x 10" to 9.6 X 10.9 cmlsec and results offield penneability tests in monitoring wells ranging from 6.7 x

10" to 6.9 x 10" cm/sec.

Bedrock encountered at IAAAP consists predominantly of limestone, with shale reported in some borings.

Site data suggest that the drift and upper bedrock aquifer are in hydraulic communication, thus comprising

a single hydraulic system. The bedrock is exposed at the surface sporadically in the southwest part ofthe

plant, around Mathes Lake, and locally along the Skunk River valley bluff south of the plant. As noted, it

is found in depths of more than 50 to 100 feet elsewhere at IAAAP. In the bedrock, groundwater occurs

primarily within open bedding planes and/or joints and flow would be influenced by the presence and

orientation of these features. Also, it is common in the upper midwest for much of the groundwater in these

bedrock units to be found in the more fractured and weathered upper sequence, just under the drift. Limited

cores obtained during site investigations indicate that fracturing and weathering is variable in the upper



bedrock units and, thus, groundwater yields from these units vary widely. Sitewide, available groundwater

levels suggest that overall flow direction in the bedrock is to the south and east, toward the Skunk and

Mississippi Rivers. The bedrock generally does not discharge to the surface or surface waters on-site except

in the Mathes Lake area and locally in the southwestern part of the lAAAP. However, discharge to the

southwest is expected in major regional drainages, including the Skunk and Mississippi Rivers. Hydraulic

conductivity data available for bedrock wells indicate a wide range of values from very permeable to very

tight. This variability can be expected to persist throughout the site area and can effect local, although

generally not regional, flow.

3.4 Surface Water

The lAAAP is drained by five water courses. Little Flint Creek drains a small area in the north of the site.

The rest of the base is drained by, west to east, the Skunk River, Long Creek, Brush Creek and Spring Creek.

Long Creek is a tributary ofthe Skunk River, which flows to the Mississippi River. Brush and Spring Creeks

are tributaries of the Mississippi River.

Stream flow within the lAAAP comprises three principal elements: surface runoff; groundwater inflow; and

discharges under NPDES. Runoff occurs during rain events, while NPDES discharges are monitored and

can be evaluated. Stream flow measurements and modeling were performed for Brush Creek and Spring

Creek to characterize stream flow for low and peak flows and to assess groundwater contributions to Brush

Creek (Harza 1997a).

Based on stream flow measurements, during typical low flow conditions (taken as May 24, 1997, which

included four preceding days with insignificant rainfall), flows in Brush Creek ranged from 0.11 cfs at the

upstream end adjacent to Line I to 2.65 cfs (including 0.65 cfs wastewater discharge), at K Road on the

downstream end. (The NPDES-permitted contributions to Brush Creek are discussed further in Chapter 4.0.)

Measured flows in Spring Creek during this event were 1.25 cfs at the upstream end of Yard C. These

flows, less the NPDES-permitted wastewater discharges, represent groundwater contributions to the creek.

During a significant wet weather event (May 25,1997, which included 0.86 inches of precipitation in 110

minutes), peak flows in Brush Creek ranged from 3.1 cfs at the upstream end to 17.3 cfs, including (1.6 cfs

of wastewater discharge), at the downstream end. Computer simulations of peak flows in Spring Creek

predicted a peak flow of II cfs at the upstream end and 19 cfs at the downstream end.



Based on these evaluations, groundwater contributions to the streams, primarily Brush Creek, appear to

increase significantly from upstream to downstream across IAAAP. This may result from increasing

hydraulic heads adjacent to the creek as it becomes more deeply incised, as suggested by a good correlation

between groundwater contributions to the creek during low flow conditions with the square of the

groundwater head as shown in the Draft Supplemental Groundwater Remedial Investigation Report, Vol I,

IAAAP, August 1997.

3.5 Chemical Data Collection and Review

A substantial database was available for review and identification of chemicals of ecological concern

(COECs). Data from the RIfFS (JAYCOR 1996), forwarded to Harza by the Omaha District USACE on CD

ROM. We also had access to more recent data (Harza 1997a). Environmental contamination within each

watershed is summarized in subsequent chapters.

3.6 Selection of Preliminary COECs

Preliminary selection of COECs was determined from a screening of physical, biological, chemical,

ecological and toxicological characteristics for contaminants found at the site. The database for identifying

COECs was the RIfFS studies of JAYCOR. Exhibit 3-2 is a flow chart of the screening process for

identifying COECs, generally consistent with the USACE's procedures for identifying COECs. Appendix

A documents our COEC identification process.

COECs were identified on a watershed basis, by first designating the basin for each of JAYCOR's soil,

sediment or water sampling locations. This being done, the following process was used for each watershed

to select COECs.

• Groundwater and soils deeper than 24 inches generally do not present a significant exposure

pathway to ecological receptors. Groundwater on the IAAAP does enter streams and then become

an exposure point, but such contaminants were assumed to be implicitly represented in the large

surface water contaminant database for the site. White-footed mice, meadow voles, and short-tailed

shrews do not usually burrow below about twelve inches.

• Non-detects and probable lab contaminants were eliminated from consideration.



• Essential nutrients generally do not present a hazard and were eliminated from consideration if

levels were less than those known to cause problems; e.g., ammonia nitrogen less than water quality

standards.

• Radiological contaminants were eliminated due to their low levels and limited distribution.

• Sediment contaminants exceeding screening levels were retained as COECs.

• Water and soil data sets were much larger than sediment. To assure that the COECs represented

general risks and not just single points, water and soil contaminants which exceeded screening levels

in 5% or more of records were retained as COECs. This eliminated contaminants with limited

distribution. However, any record ofa chemical known to biomagnify in food chains was retained

as a COEC, regardless oflimited distribution.

Chemical data passing through this screening process were retained as COECs. Aquatic ecotoxicity

thresholds were taken from the State of Iowa chronic water quality standards for limited resource waters,

guidance from the USEPA Biological and Technical Advisory Group (BTAG), the ECOTOX thresholds

database (USEPA 1996) and, for explosive compounds, USACE (1996). Soil ecotoxicity thresholds were

taken largely from the BTAG guidance. Appendix A lists the maximum values for each environmental

contaminant in the four watersheds, for soil, surface water and stream sediment, and identifies COECs that

warrant more detailed evaluation of risk.

For the field studies, it was assumed that, while dozens of chemicals could potentially be identified as

COECs, only explosives and biomagnifying chemicals were retained for analysis of residues in tissues. Later

it was determined that mammal tissue samples should be tested for additional metals for use in model

prediction confirmation.

3.7 Selection of Key Receptors

It was observed during the field reconnaissance that potential contaminant transport routes are primarily

water borne, and include:

Jows Army Ammunition PlantEcological Risk Assessment Addendum (Draft Final)

March /7, /998Page 3·/0

• Upland soil loss and sediment transport through surface runoff,

• Groundwater movement, which involves movement ofpotentially contaminated groundwater toward

the major drainages and surface discharge into stream channels, and

• NPDES discharges to surface water draining the IAAAP.

All contaminant transport is likely to be concentrated by or to follow existing surface drainage patterns.

Sediment transport and groundwater movement would likely concentrate or discharge into the riverine flood

plains adjacent to the major stream channels traversing the plant property: Spring Creek, Brush Creek, Long

Creek, and the unnamed tributaries of the Skunk River on the southwest side of the IAAAP. The presence

of routine flood waters as well as deposition of sediment in the flood plain, in large part as berms or levees

paralleling the stream banks, presents an opportunity to assess the significance of these transport routes.

These sediment berms create a slight depression out of the remainder of the flood plain area away from the

stream channel, between the berms and the surrounding upland slopes. Many of these depressional areas

have hydric soils and support emergent and forest wetlands. The presence of routine flood waters, including

the deposition of sediment on existing soils, provides a habitat for exposure to all possible contamination

pathways. Soils and biota inhabiting these flood plain areas are indicative of the significance of watershed

contaminant transport routes. Their usefulness in this regard is the reason the flood plains were selected for

this ERAA.

It was assumed that all aquatic COEC exposure pathways lie within the aquatic ecosystem; that is, terrestrial

contributions to the aquatic biota are minimal or non-existent. Therefore, although direct exposure to a

contaminant in water or stream sediment may be a pathway, the principal exposure path is anticipated to be

through the aquatic food chain. The selection of receptors, and assessment and measurement endpoints is

based on this assumption, and contaminated sediment as an exposure pathway is implicitly addressed through

a community health endpoint.

Selection of key aquatic receptors focuses on two levels of biological organization: an individual fish

species, and the benthic community. Because of its listing as a threatened species by the State of Iowa, the

orangethroat darter (Etheostoma spectabile) was selected as a key receptor. However, because of the

orangethroat darter's threatened status, the fantail darter (E.jlabellare) and the Johnny darter (E. nigrum)

were used as surrogates. Both of these darters have similar food habits to the orangethroat.


March 17, 1998Page 3-11

The benthic community was selected as a key receptor because of its place in the food chain for fish,

waterfowl, wading birds and aquatic mammals. Because certain components of the benthos are sensitive to

pollution, it is also frequently utilized to measure the health ofthe aquatic biological community.

Considering the preliminarily identified contaminant transport routes, key receptors include plant and animal

species found throughout the aquatic and terrestrial flood plain environment. Selection of animal species

as target receptors have the advantage that such species, high on the food chain, would accumulate and

concentrate lower level plant and animal accumulation sources into the receptor.

Being a voracious vermivore/insectivore, the short-tailed shrew ·should bioaccumulate contaminants from

lower order accumulators. Additionally, shrews are common prey for raptors and higher order carnivores.

The habits of the mammals analyzed for contaminant residues are summarized below, as taken from. The

shrew inhabits a wide range ofhabitats, but prefers cool, moist habitats because oftheir high metabolic and

water loss rates, and (if habitat conditions are suitable) should be readily found in the flood plain areas of

lAAAP (USEPA 1993; Schwartz and Schwartz 1981). Home ranges for shrews are, at most, one hectare,

so body residues would reflect local exposures from contaminants. Nests are usually under rocks, logs, or

other objects and connected to surface runways or tunnels that may be as deep as 20 inches (Jackson 1961).

Short-tailed shrews are primarily carnivorous; they feed mostly on earthworms (which consume soil) and

invertebrates that consume plants and plant material. Additionally, they will consume some plants directly.

As such, their body burdens will reflect the exposure pathways through ingestion of both plants and animals.

The advantage in selecting small mammals like shrews as study receptors is their limited home range; larger

flood plain inhabitants such as raccoon have much greater ranges and contaminant body burdens may not

directly reflect the trapping location.

During field activities, we found that the short-tailed shrew was not the most common small mammal in

IAAAP floodplains. White-footed mice (Peromyscus leucopus) and, to a lesser extent, meadow voles

(Microtus pennsylvanicus) were more common and would serve as an equally suitable receptor for study.

As allowed in the WQAPP, we substituted these other small mammals for the short-tailed shrew for use as

an indicator of food chain uptake.

The white-footed mouse and the meadow vole have numerous similarities with the short-tailed shrew. Both

the white-footed mouse and the meadow vole are similar in size and mass to the short-tailed shrew, and all

are active both day and night. The diet of the white-footed mouse, while not as varied as the short-tailed


March 17, 1998Page 3-12

shrews, includes arthropods, seeds, and other vegetation. The white-footed mouse is abundant in areas with

a canopy such as brushy fields and deciduous woodlots, and its home range is from It, to I It, acres. White

footed mice usually nest in trees and shrubs, but may nest in rock crevices, underlogs, or in burrows dug by

other species. The white-footed mouse is preyed upon by hawks, owls, snakes, and carnivorous mammals

including the short-tailed shrew. The meadow vole is herbivorous, eating grasses, seeds, grain, bark, but it

probably eats some insects as well. Like the short-tailed shrew, the meadow vole lives in grassy fields with

moist to wet habitat. Jackson (1961) indicates that nests may be above ground or as deep as nine inches.

The home range of the meadow vole is 1/10 to I acre. The meadow vole is preyed upon by hawks, owls,

shrews, badgers, and foxes.

3.8 Ecological Assessment and Measurement Endpoints

Aquatic assessment endpoints are the viability ofindividuals ofthe state-listed threatened orangethroat darter

and the health of the benthic macroinvertebrate community. To assess the risk to the reproduction of

orangethroat darter population, the levels of COECs bioaccumulated in individuals of fantail and Johnny

darters were measured or estimated from models. The significance ofthese levels was then evaluated using

literature-based benchmarks for toxicological effects (described in Chapters 4 through 7). The health of the

aquatic benthic community was measured using the Rapid Bioassessment Protocol 111 (RBP) developed by

the USEPA (Plafkin, et al. 1989). In this technique, community indices obtained for the sample sites are

compared to the indices found at a reference (or control) station. Samples were evaluated using eight

common community metrics:

• Species Richness (the number oftaxa identified)

• Modified Hilsenhoff Biotic Index

• Ratio of Scraper and Filtering Collector Functional Feeding Groups

• Ratio ofEPT (Ephemeroptera, Plecoptera, Tricoptera) and Chironomidae Abundances

• Percent Contribution of Dominant Taxon

• EPT Index (number ofEphemeroptera, Plecoptera and Trichoptera taxa)

• Community Loss Index ([reference species richness -species in common] / species richness)

• Ratio of Shredder Functional Feeding Group and Total Number of Individuals Collected in

Coarse Particulate Organic Matter


March 17. 1998Page 3-13

In the RBP, the ratio of most metrics for a sample and the corresponding metrics for its reference station are

used to assign a Biological Condition Score that has a value of 0,2, 4 or 6. Biological Condition Scores

derived from the Percent Contribution of the Dominant Taxon Index and the Community Loss Index are

compared to standard ranges rather than the reference station values. The sum of scores for a station is

expressed as a percentage of the sum for the reference station. This percentage relates to Biological

Condition Categories according to the following definitions:

>83%

54-79%

21-50%

Nonimpaired Comparable to the best situation to be expected within anecoregion. Balanced trophic structure. Optimum communitystructure (composition and dominance) for stream size and habitatquality.

Slightly impaired Community structure less than expected. Composition (speciesrichness) lower than expected due to loss of some intolerant forms.

Moderately impaired Fewer species due to loss of most intolerant forms. Reduction inEPT index.

<17% Severely impaired Few species present. If high densities of organisms, thendominated by one or two taxa.

Percentages intermediate to the above ranges require subjective judgement aided by habitat assessment and

physicochemical data.

The assessment endpoints for the terrestrial ecosystem are the health of the vascular plant community and

the viability of wildlife populations. Additionally, because offederal listing as a threatened species, the

viability of the bald eagle (Haliaeetus leucocephalus) was assessed. To assess the health of the vascular

plant communities potentially affected by chemical contamination or land use practices, the forest

community structure quality index, as determined by Horton et al. (1996), was the measurement endpoint.

Non-contaminated reference sites were utilized to compare with contaminated areas to qualitatively, and in

some cases quantitatively, measure potential effects of ecological stress. All terrestrial sites at lAAAP have,

or have had in the past, some degree ofhuman disturbance of the environment (various periods oflogging,

clearing, agricultural cropping, pasture, burning, homesteads, road development, contaminant remediation,

etc.). Potential impacts from chemical contamination may be masked to varying extent by human

disturbance. Such human disturbance at each sample site was considered in evaluation of the potential

effects of chemical contamination on the terrestrial environment.


March 17, 1998Psge 3·14

The assessment endpoint for terrestrial high trophic level consumers exposed via their diet is reduced

reproductive success. The measurement endpoint is body burdens of COECs in small mammals. Utilizing

the body burdens of contaminants in small mammals and darters, the likely body burdens of those

contaminants in the bald eagle were projected and evaluated using literature-based benchmarks for

toxicological effects.

Iowa Army Ammunition PlantEcologicsl Risk Assessment Addendum (Draft Final)

March 17, 1998Paga 3-15

3.9 Conceptual Site Model

Exhibit 3-3 is a Conceptual Site Model showing contaminant sources, exposure pathways and ecological

receptors. Primary sources of contamination at IAAAP are the ordnance production lines, waste

management sites and burning/detonation sites. Contamination leaves these areas via atmospheric releases,

infiltration to groundwater, surface runoff from spillage as well as rain runoff and soil erosion, and NPDES

discharges.

Ecological receptors are exposed to the contamination principally through the surface runoff mechanism.

Aquatic receptors are exposured in streams by direct contact with dissolved COECs in the water, and for

sediment dwelling species, by contact with COECs in sediment pore water. Ingestion by these exposed

receptors begins to transport the contaminant up the food chain.

Terrestrial receptors include both plants and animals. Plant uptake of contaminants directly from the soil

as well as direct incidental ingestion ofcontaminated soil provides entry to the terrestrial food chain for the

COECs. Some COECs are slow to degrade and may pose a risk for years or decades following their release

to the environment. If that chemical is also hydrophobic (having an affinity for dissolution in oil or fatty

tissue), it will tend to biomagnify with trophic level, and pose the greatest threat to top-order carnivores such

as raptors, coyote, or badger.

Evaluation of COEC risk to ecosystems can be performed in any number of ways. COEC intake by target

populations or individuals can be compared to known toxicity values for derivation of a classic hazard

quotient. Alternatively, community stress from COEC exposure can be measured and compared to an

unstressed reference community. Our ERAA has taken both of these approaches, in order to reduce

uncertainty, to evaluate all potential exposure routes, as well as to increase our understanding of population

and individual exposure and reaction to munitions chemicals.

3.10 Field Methods and Materials

Field activities were defined in the Work/Quality Assurance Project Plan (Harza 1997b), prepared in

consultation with the environmental staffof the IAAAP, USACE and USEPA. The field program included

the following:


March 17, 1998Page 3·16

• Soil and surface water sampling

• Stream habitat measurements

• Collection ofbenthic macroinvertebrates andfishes from site streams

• Trapping ofsmall mammals

Specific field activities required in each task are delineated in the following sections including, as

appropriate: media sampled, number and location of samples, general sampling methods, and field and

laboratory methods associated with each task. Sample analysis was performed by Applied Research

Development Laboratory (ARDL) under subcontract to Harza. Investigation locations are shown on Exhibit

3-4. Sampling locations, descriptions, designations, and rationale are described in Table 3-3.

Table 3-3. Sampling Locations, Descriptions, Designations and Rationale

Basin Description Designation Sample Types Rationale

Long Creek West boundary oflAAAP LCI Soil, Fish, Reference siteMammal,Benthos

Long Creek At Road N; upstream of LCn Benthos Potential reference siteYardH

Long Creek At Road L, upstream of LCT2 Benthos Potential contamination from LineYard G; unnamed tributary 800draining Line 800

Long Creek Within Yard G; tributary LCn Benthos Potential contamination from Lineto Long Creek draining 800Line 800

Long Creek At Road K LC2 Soil, Fish. Downstream boundary oflAAAP;Mammal, site of sediment sample 7N (HarzaBenthos I997a)

Skunk River Unnamed tributary on west SRn Benthos Receiving water for NPDES outfallboundary of lAAAP 014; site of sediment sample 7Q

(Harza 1997a)

Skunk River Unnamed tributary SRT2 Benthos Site of sediment sample 7P (Harzaimmediately east of above I997a)unnamed drainage

Brush Creek Line I, upstream of all BC9 Soil, Mammai, Upstream of all NPDES outfalls;NPDES discharges Benthos possible reference site

Brush Creek Line I, downstream BCIO Soil, Mammal, Downstream of active NPDES outfallsboundary of tributary Benthos 011,012,051, & 052 plus severaldraining Line SA inactive outfalls

Brush Creek Downstream of Road D BCI Benthos Site of sediment sample 7E (Harza1997a)

Iowa Army Ammunition PlantIowa Army Ammunition Plant March 17, 1998/Rev. JE~/IIl/i8k4AII,_melltlP:rl6lBnIJlmt f!JNJft Final)

March 17. 1998(S/t"/JE83>/I3)

Table 3-3. Sampling Locations, Descriptions, Designations and Rationale

Basin Description Designation Sample Types Rationale

Brush Creek Upstream of Road I BC2 Benthos Sediment sample site 7F (Harza1997a); upstream of tributarydraining lines 7, 9, & 3

Brush Creek At Road H BC3 Soil, Mammal, Upstream ofWWTP (NPDES 013);Benthos sediment sample site 71 (Harza 1997a)

Brush Creek At Road H BC4 Benthos, Fish Downstream of WWTP; sedimentsample site 71 (Harza 1997a)

Brush Creek Downstream of BC5 Fish, Benthos Sediment sample site 7J (Harzaundesignated road between 1997a)YardsE & D

Brush Creek At Road K BC6 Soil, Fish, Sediment sample site 7K (HarzaMammal, I997a)Benthos

Brush Creek Southern boundary of BC7 Benthos Along contaminant gradientlAAAP

Brush Creek Hunt Road BCS Fish, Benthos Along contaminant gradient

Spring Creek At Road G SCI Soil, Fish, Reference siteMammal,Benthos

Spring Creek At Road P SC2 Soil, Fish, Sediment sample site 7A (HarzaMammal, 1997a); downstream of EDABenthos

Spring Creek Upstream of undesignated SC3 Benthos Sediment sample site 7B (Harzaroad east of Yard D 1997a)

Spring Creek Downstream boundary of SC4 Soil, Fish, Sediment sample site 7C (HarzalAAAP Mammal, I997a)

Benthos

Spring Creek At Brush College Road SC5 Benthos, Fish Along contaminant gradient

Spring Creek At Hunt Road SC6 Benthos, Fish Along contaminant gradient

3.10,1 Soil Sampling

Soils deposited in the alluvial flood levees during high flow events were collected at locations shown on

Exhibit 3-4, at the same locations where small mammal trapping occurred. Soils were analyzed for mercury

and selected other metals, explosives, pesticides and PCBs, Samples were collected using stainless steel

hand trowels and were limited to the organic "0" and "A" soil horizons, to depths no greater than three

inches, and samples were composited. The composite samples were composed of approximately equal

portions from at least twelve locations disbursed throughout the mammal sampling area. The composited

sample was mixed well in the field, and large stones and organic debris removed prior to placement in pre

cleaned glass jars supplied by the laboratory. The samples were logged by the field technician, labeled and

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Finsl)

March 17. 1998Page 3·18

placed in coolers for shipment to ARDL for analysis. The trowels and bowls were decontaminated between

sampling sites by detergent washing and repeated rinsing with distilled water. Standard chain-of-custody

procedures were used during handling and transferral of the samples.

3.10.2 Surface Water Sampling

Surface water was tested in situ for dissolved oxygen, temperature, and conductivity during each collection

of aquatic macroinvertebrates. Field measurements were made using instruments precalibrated in Harza's

office prior to use in the field. Temperature was measured using a mercury thermometer. Dissolved oxygen

(DO) was measured using a Yellow Springs Instrument (YSI) Co. Model 57 DO meter, recalibrated in the

field to air according to the manufacturer's instructions. Conductivity was measured using a YSI Model 33

Salinity-Conductivity-Temperature meter.

Surface water was sampled on October 27, 1997 to speciate aquatic metals into dissolved and filtrable

fractions. Samples were collected at six locations on the plant: SCI, SC4, BC9, BC6, LCI and LC2. Two

bottles were filled at each sampling location. One bottle was acidified in the field for preservation of total

metals. The samples were logged by the field technician, labeled and placed in coolers for shipment to

ARDL for analysis. Again, standard chain-of-custody procedures were used during handling and transferral

ofthe samples. In the laboratory, the unacidified water sample was filtered through 0.45f!m-pore membrane

filters prior to acidification and analysis of dissolved metals.

3.10.3 Stream Habitat Measurements

Physical habitat measurements were made at each aquatic macroinvertebrate collection site. Results of this

measurement process are presented in Appendix E. Each sampling site was photodocumented at the

upstream and downstream termini of the transect.

3.10.4 Aquatic Macroinvertebrate Sampling

Exhibit 3-4 shows the sites sampled for assessing the health of the aquatic benthic community. Sample

collection utilized the Rapid Bioassessment Protocol III methods (Platkin, J. L. et al. 1989). The level of

detail in Protocol III is consistent with a Tier I ERA. Two types of substrates were sampled, with the data

processed separately: coarse particulate organic matter and riffle/run samples.


March 17, 1998Page 3·19

Sampling of coarse particulate organic matter (CPOM) was performed separately to characterize functional

feeding groups in the benthos. CPOM includes plant parts such as leaves, twigs and bark. A variety of these

forms were examined by the field crew. Neither newly deposited nor fully decomposed CPOM was

collected. Organisms were classified strictly as either shredders or non-shredders using the method of

Cummins and Wilzbach (1985); taxonomic identification of CPOM samples was not done. The numbers

of shredder individuals and the number of total individuals in the CPOM sample was recorded.

Riffle/run habitat was also sampled. Areas with relatively fast current over a cobble or gravel substrate were

located and sampled three times or more with a Surber sampler to obtain approximately 100 individuals at

each site. The Surber samples were combined for processing. If submerged fixed structures, such as logs,

pier pilings, or bridge abutments were present, these were also sampled by hand picking and the organisms

added to the sample. Field inspection was done on the sample to obtain a preliminary assessment of

presence/absence of major groups and to determine if sampling efforts were adequate to obtain 100

individuals. If a site was found to be too severely impaired to support organism abundance allowing

collection of 100 individuals, then the field crew noted the effort in the field log.

3.10.5 Fish Sampling

General sampling areas are shown on Exhibit 3-4. Riffle areas were seined or electrofished for collection

of darters. In general, seining was found to be a more effective method for collection of darters.

Orangethroat darter, if found, was noted in the field logs and returned immediately to the stream. Darter

species were identified using the key of Smith (1979). Darters collected at each site were identified,

enumerated, and weighed. A composite sample ofwhole fish weighing at least 38 g was placed on ice in

a labeled container, frozen, and shipped in an insulated container to ARDL for analysis. Standard chain-of

custody procedures were used during handling and transferral ofthe samples.

A single species, either Johnny darter or fantail darter, was used for the sample. At one site (SC5 on Spring

Creek), the mass of a single species sufficient for analysis could not be collected and two species were

combined to obtain a sample. Table 3-4 lists the species analyzed at each station. Whole fish were analyzed

for explosive chemicals, select metals, and biomagnifYing COECs: mercury, pesticides and PCBs.


March 17, 1998Page 3-20

Table 3-4. Darter Species Collected at IAAAP, 16 July tbrough 25 July 1997

Watershed Site Species Present Species Analyzed for COECs

Long Creek LCI None present None

Long Creek LC2 Johnny and Fantail darters Fantail darter

Brush Creek BCS Orangethroa~ Johnny, Fantail darters Fantail darter

Brush Creek BC6 Orangethroat, Johnny, Fantail darters Fantail darter

Brush Creek BCg Orangethroat, Johnny, Fantail darters Fantail darter

Spring Creek SCI Orangethroat, Johnny darters Johnny darter

Spring Creek SC2 Orangethroat, Johnny, Fantail darters Fantail darter

Spring Creek SC4 Orangethroat, Johnny, Fantail darters Johnny darter

Spring Creek SCS Orangethroat, Johnny, Fantail darters Johnny and Fantail darter

Spring Creek SC6 Orangethroat, Johnny, Fantail darters Fantail darter

3.10.6 Small Mammal Sampling

Small mammal sampling areas are shown on Exhibit 3-4. Pit traps baited with peanut butter or in association

with drift fences were the primary devices used to capture the mammals. Live traps and snap traps were also

tried, but were generally not successful in capturing animals. Raccoons regularly vandalized the pit traps

by digging them up, destroying the drift fences and removing the bait. The traps were all set in flood plain

forests immediately adjacent to the streams, and were spaced over a maximum area of about one-half

hectare. All traps, once set, were checked at the beginning and end of each day. Animals captured in the

traps were removed, weighed, placed in double plastic bags, labeled and placed in a cooler until frozen later

that day. Organisms were identified, and checked by mammalogists ofField Museum ofNatural History,

Chicago IL. Frozen animals were shipped by overnight courier to ARDL for analysis. Standard chain-of

custody procedures were used during handling and transferral ofthe samples. Whole bodies were analyzed

for mercury and other selected metals, explosives, pesticides and PCBs.

In total, 48 small mammals representing six species were captured during the field studies. The effort

included over 250 trap-days of baited pit falls, 42 trap-days of drift fences, and 24 trap-days of live traps.

Preliminary trials using snap traps were unsuccessful and they were not utilized during the principal field

collection efforts.

Seventeen animals were shipped to ARDL for analysis of whole-body contaminant residues. All animals

with a minimum body weight of 38 g were analyzed for mercury, lead, pesticides/PCBs, and explosives;


March 77, 7998Page 3-21

animals captured in Brush Creek or Spring Creek watersheds were also analyzed for silver, thallium and

chromium. Animals weighing less than 38 g were not analyzed for explosives because 30 g of tissues are

required for explosives analysis. Tissues sent to the laboratory for analysis included ten white-footed mice,

three short-tailed shrews and four meadow voles (Table 3-5).

Table 3-5. Numbers of Small Mammals Captured at IAAAP, 16 July through 25 July 1997

Watershed

Spring Creek Brush Creek Long CreekScientific Name Common Name

Peromyscus leucopus White-footed mouse 8 7 8

Reithrodontomys mega/ooo Western harvest mouse 1 0 0

Microtus pennsy/vanicus Meadow vole 1 3 0

Blarina brevicauda Short-tailed shrew I 0 3

Sore:x cinereus Masked shrew 7 5 2

Sea/opus aquaticus Eastern mole 0 2 0

Total 18 17 13


March 17, 1998Page 3-22

EXHIBITS

EXHIBIT 3-1

'.I

__ ~JI

I

jLI.-J. . _

,IIIII-II

,

-128 I

ABBREVIATIONS:

F Forest

BF Bottomland Forest (flood plain)

0 Old Field

W Wetland

A Agriculture

B Base Facilities

P Open Water, Pond/Lake

R Residential

D Disturbed (barren)

LAND USE MAPIOWA ECOLOGICAL RISK ASSESSMENT ADDENDUM

IOWA ARMY AMMUNITION PLANTMiddletown, Iowa

Scale O;..._...:;20::;O"'O'-=4:;:O"O:;;O~....:6:;;O"O"O=..;:8"OO,OFeet

I--IARZA. Consulting Engineers and Scientists

". ---;'1~

ti~

"...._------------------------------------------------------------------------------------------_......

G:\iowaladdel'ldum\\exh3·2.cdr

JAYCOR RifFS soil, surface water, sedimentcontamination database

Identificationof watershed

for each sample

Are soil samplestaken from greater

than 24" depth?

NO

Has sample beenflagged for labcontamination?

NO

...---"'" ".~

YES ~ Eliminate as an exposure pathway li~~~

,..-=---'.

YES ~ Consider sample results invalid 11 ~ ~ ~

Essential nutrient? ------. YES ~ Not Cl significant hazard INOf---t---t

Sediment Data Surface Water Data

DoesChemical

Biomagnify?

YES>--

Add chemicalto aquatic

COEC list forwatershed

Soil Data

DoesChemical

Biomagnify?~

Add chemicalto terrestrial

COEC list forwatershed

No No

DoesNO

Do moreNO NO

sample exceed Ian 5% of samples

WDo more ..=.. '.

Ecotox or BTAG threshol at site exceed IWQS, than 5% of samples

H_~levels?Ecotox, or BTAG at site exceed BTAG'hreshold levels? thresholds?

YES YES

I I•I I

Add chemical to aquatic COEClist for watershed

J---lARZA Consulting Engineers and Scientists

YES

~Add chemical to terrestrialCOEC list for watershed

mSCREENING AND IDENTIFICATION OF COECs ~

IOWA ECOLOGICAL RISK ASSESSMENT ADDENDUM Q?IOWA ARMY AMMUNITION PLANT ~

Middletown, Iowa N

- PRIMARY SOURCES PRIMARY RELEASE _

MECHANISMSSECONDARY

SOURCESSECONDARY

RELEASEMECHANISMS

--CONTAMINATED PRIMARY RECEPTORSMEDIA

SECONDARYRECEPTORS

EXHIBIT 3-3

TERTIARYRECEPTORS

.. Runoff f--~

Measurement Endpoint Measurement Endpoint

.. Benthic Macroinvertebrate Contaminant Concentrations~ Spills and Leaks f-- Community Structure In Darters

Active and InactiveOrdnance Production r----- I I

Facilities (Lines) · Particulate I I..Emissions

f-- I II I

· WasteWater I Aquatic Biota I- I I~

Discharges Benthic Macroinvertebrates

A Kr... Surface Water ... FishRunoff ,. V ~ Aquatic PlantsSediments

Aquatic Mammals... Fish Bald Eagle• Runoff f-- ----. Herbivorous Mammals ~ Coyote

Herptiles BadgerActive and InactiveBirdsLandfilislWaste • Spills Surface/Sub- • Surface Soil r\ • Terrestrial Biota It• Surface Soils ~ y •Pits

Soil MacroinvertebratesVegetation I

• Infiltration/f-- I Burrowing Animals I• Percolation

I I'-----lI I4 .1Leaching . Groundwater I I

Particulate I IEmissions t--

1 I

Active and InactiveInfiltration/

Measurement Endpoint Measurement EndpointBurning/Detonation - Vascular Vegetation Contaminant Concentrations

Sites PercolationCommunity Structure In Shrew Tissue

Runoff t--

(Modified from JAYCOR, 1996)

-~;

!J. CONCEPTUAL SITE MODEL~ IOWA ECOLOGICAL RISK ASSESSMNET ADDENDUM

!l"~S"L IO_W_A_A_R_M_Y_A_M_M_U_N_IT_IO_N_P_LA_N_T-.IMiddletown, IowaI--IAR.ZA. Consulting Engineers and Se/enosts

EXHIBIT 3-4

LEGEND:

• SAMPLING SITES

~ ROAD NAME

_ .•_ •.- PLANT PROPERTY BOUNDARY

NOTE:

ADDITIONAL SITES NOT SHOWN ON MAP INCLUDE:

SC5 • Spring Creek at Brush College Road

SCB - Spring Creek at Hunt Road

BCB - Brush Creek at Hunt Road

SAMPLING LOCATION MAPIOWA ECOLOGICAL RISK ASSESSMENT ADDENDUM


8000 Feel60004000

Consulting Engineers and Scientists

SRT1 SRT2 LC1 LC2 LCT1 LCT2 LCT3 BC1 BC2 BC3 BC4 BC5 BCB BC? BCB BCQ BC10 SC1 SC2 SC3 SC4 SC5 SCB

MAMMALS • • • • • • • • • •SOILS • • • • • • • • • •BENTHOS • • • • • • • • • • • • • • • • • • • • • • •FISH • • • • • • • • •

scale 0 2000

I--IARZA

tII

i81.- ...

4.0 BRUSH CREEK WATERSHED

4.1 Watershed Description

Brush Creek drains the central portion ofthe IAAAP, including the majority of industrial operations. Ofthe

four watersheds within the IAAAP, Brush Creek has the most activity associated with facility operations. The

watershed contains Lines 1,2,3,6,7,9, 800, the former Line 800 Pink Water Lagoon, the former Line 1

Impoundment, and parts of Lines 4A and 5A.

4.1.1 Physical Description

Brush Creek originates as a spring in the northern portion ofthe site and exits the lAAAP at the southeastern

boundary. Brush Creek has a drainage area of approximately 5,000 acres within the lAAAP. The floodplain

at the southern boundary of the site is about 200 feet wide, and the stream is incised approximately 90 feet

below the neighboring uplands. Brush Creek flows into the confluence of the Skunk and Mississippi Rivers

approximately nine miles southeast of the site.

4.1.2 Land Use/Land Cover

Exhibit 3-1 is a map of land use at the lAAAP, and tabulated areas of each classification for this basin are

presented in Table 4-1.

Table 4-1. Brush Creek Watershed Land VsefLand Cover

Land UselLand Cover Acres Percentae:e

Upland Forest 563 11%

Floodplain Forest 221 4%

Old Field 981 20%

Other Wetland 7 0%

Al!riculture 1,909 38%

Base Facilities 681 14%

I Goen Water, PondlLake 15 0%

Residential 0 0%

Disturbed (barren) 107 2%

Base Facilities/Old Fields 529 11%

Total 5,014 100%



IAAAP fenced compounds contain most of the buildings and are mainly upland habitats colonized by

principally non-native or introduced species ofvegetation. There are also large row crop areas leased to local

farmers. The predominant natural vegetation community is the temperate deciduous forest, in its early to

moderate successional sere, which occurs on the slopes and lowlands along the stream.

In 1996, an inventory and assessment ofhabitats and biota ofthe IAAAP was published (Horton et at.). While

their objective was to assess the entire facility, they focused on natural areas along creeks and drainageways,

where temperate deciduous forest predominates. At IAAAP, the current flood plain forest is characterized by

the dominance of cottonwood (Populus deltoides), black willow (Salix nigra), sycamore (Platanus

occidentalis), honey locust (Gledi/sia triacanthos), green ash (Fraxinus pennsylvanica), northern hackberry

(Celtis occidentalis), ehn (Ulmus spp.), poison ivy (Rhus radicans), grape (Vi/us spp.), multiflora rose (Rosa

multiflora), brambles (Rubus spp.), and numerous species offorbs, grasses and sedges (Horton et al. 1996).

4.1.3 Protected Resources

Although the bald eagle (Haliaeetus leucocephalus), listed as threatened in federal regulations, has been

observed to consume fish from Mathes Lake in the Long Creek watershed (JAYCOR 1996), Horton et al.

(1996) found no federally-listed endangered species on the lAAAP property. Horton et al. (1996) did report

one state-listed threatened fish species, the orangethroat darter (Etheostoma spectabi/e), in the Brush Creek

watershed at the IAAAP. The presence ofsignificant numbers of orangethroat darter throughout Brush Creek

was confirmed by Harza ecologists during the field program. No other state-listed threatened/endangered

species were found in the IAAAP portion of the watershed. Biological resources of special concern found

within the Brush Creek watershed are displayed in Table 4-2.

Table 4-2. Protected Species in tbe Brosh Creek Watershed

Locality Species

Middle Augusta Road crossing, W of Yard D. orangethroat darterSec.16, T69N, R3W

Plant Road K crossing. orangethroat darterNW 1/4 ofNW 1/4, Sec. 22, T69N, R3W

Outside SE comer oflAMP, HWlt Rd Bridge. orangethroat darterSec.26, T69N, R3W

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Fina/J


4.1.4 Geology and Hydrogeology

Brush Creek is slightly incised into the glacial drift uplands in the northern part of the area, becoming more

deeply incised to the south and exiting the property near the southeast corner. Limestone bedrock is relatively

deep, and the glacial drift is thick, beneath most ofBrush Creek, due primarily to a buried bedrock valley which

crosses beneath the central reaches ofthe creek and the downstream reaches of Spring Creek. The drift exceeds

100 feet thick under much ofthe north part ofthe drainage, where it consists predominantly of low permeability

silty clay till with scattered thin sand or silt seams. The drift remains thick further south and consists of silty

clay till with comparatively more frequent silty and sandy seams and interbeds. Near the property boundary,

the creek flows over the west edge of the buried bedrock valley. Thus, bedrock is very shallow beneath the

west side of the creek valley and deep to the east. As elsewhere within IAAAP, shallow groundwater flow

parallels surface topography discharging to the Brush Creek and major tributaries. Groundwater levels

measured in shallow wells within the Brush Creek watershed were generally five to ten feet below ground level

in the spring of 1997. Potentiometric measurements indicate that both the upstream and downstream reaches

of the creek are being recharged by groundwater from both the east and west sides. Downward vertical

gradients also are present throughout the area within the drift and between the drift and underlying bedrock.

4.1.5 Facilities

The facilities in the Brush Creek Watershed include Lines 1,2,3, part of 4A and 5A, 7, 9, 800, the Pesticide

Pit and the Main Sewage Treatment Plant. Lines I, 2, 3 and 800 are reported by JAYCOR (1996) to

contribute the most contamination to the surrounding areas. Briefdescriptions of the facilities in the watershed,

as described in the RI report (JAYCOR 1996), are contained in Table 4-3.

Table 4-3. Facilities in Brush Creek Watershed

Facility Size! Period of Function WastewaterlWasteBldgs Operation Contaminants

of Concern

Line 1 190 1941 to Cartridge, missile Treated by carbon adsorption, Explosivesacres/22 present warhead, and grenade discharged to drainage ditches to Metalsbldgs loading and packing. NPDES pennitted outfalls (#12). VOCs

Line 2 140 I 940s-1 947 Load, assemble, and Treated in adjacent filter houses, Explosivesacres! and 1949 to pack ammunition. discharged to NPDES pennitted Metals70 bldgs present outfalls (#21, #22). VOCs

SVOCs

Iowa ArmV Ammunition PlantEcological Risk Assessment Addendum (Draft Final)


Table 4-3. Facilities in Brush Creek Watershed

Facility Sizel Period of Function WastewaterlWasteBldg. Operation Contaminants

of Concern

Line 3 149 1941-1945 Metal Cleaning Treated by settling tanks, filtration, and Explosivesacres! 56 and 1949 to operations. carbon adsorption, discharged by Metalsbldgs present drainage ditches to NPDES pennitted VOCs

outfalls (#32, #33).

Line4A 21 acres! 1941-1945 Detonator production Treatment tanks with sludge of settled Explosives12 bldgs and 198210 and assembly. metals shipped ofT-site, and treatment Metals

present sumps for RDX contaminatedwastewater, discharged to NPDESoutfall (#41), presently not discharging.

Line 5A 33 acres! 1942-1945 Component lines for Discharged to intennittent Explosives17 bldgs and 1949- pelletizing and drainageways to NPDES outfalls (#51,

date, assembly of explosives. #52), presently not discharging.currentlyinactive

Line 6 30 acres! 1941 to Production. storage, Treated wastewater percolated into Explosives34 bldgs present shipping of detonators, ground, overflow to tributary of Brush Metals

relays. and hand Creek; wastewater treament sludgegrenade fusers. also generated. No wastewater

generated presently.

Line 7 9 acres 1941-1970 Fuse and blank Building washdown waste discharged Explosivesloading, assembly and to gravel-lined sumps and leached into Metalspacking (LAP) facility. ground, overflow ran into natural

drainageways.

Line 9 9 acres! 1942 to Component production Waste solvents stored for 9 months. Explosives15 bldgs present facility and LAP Metals

VOCs

Line 800 17.5 I941-date, Ammunition Closed loop metals wastestream~ Explosivesacres/I 8 currently renovation, fuse metals collected and sold as scrap. Metalsbldgs inactive demilitarization. Line 800 Pink Water Lagoon used tor

-------- ------- -------- --------------- emuent disposal. Settling! carbonLine 800 5 acres 194310 Disposal of emuent filter system treats generated process

Pink Water (4 ft present from Line 800. water. NPDES pennitted outfalls (#81,Lagoon deep) #82), currently not discharging.

Pesticide 8 sq. ft. 1968-1974 Lined pit for disposal Pit and contents were excavated, PesticidesPit of small amounts of containerized. and transported to inert SVOCs

pesticides and off-site landfill in 1995.herbicides and rinsate

Sewage I acre 1940s to Main Treatment Plant Wastewater through Imhoff tank, MetalsTreatment present trickling filter. secondary clarifier,

Plant chlorine contact chamber. sludgedrying beds and discharged to NPDESpermitted outfall (#13).

Iowa Army Ammunition PlantEcological Risk. Assessment Addendum (Draft Final)


4.1.6 Watershed Contamination

4.1.6.1 Soils. There is evidence of explosives, metals, and VOC contamination in soils located in the

vicinity ofproduction fucilities in the Brush Creek watershed. The contaminants are generally localized near

building operations and in drainageways. Explosives were reported in soils up to ten foot depths in samples

collected from the settling ponds northeast of Line 800. Metals contamination was reported to be widespread,

lead being the most prevalent metal reported. Surficial soils tended to be the most contaminated;

concentrations generally decreased with depth (JAYCOR 1996). Contamination in soils in the facilities in the

Brush Creek Watershed are summarized in Table 4-4, based on the RI report (JAYCOR 1996), except when

referenced.

Table 4-4. Soil Contamination in Brush Creek Watershed

Facility Soil and Soil Gas Sampling Results

· Explosives contamination found in near-surface soils with HMX, RDX, 2,4,6-lNT as high asLine 1 1,600; 3,700; and 9,200 ~g1g, respectively.

· Metals contamination more widespread than explosives contamination. Lead is generally the metalreported at highest concentration (as high as 13,000 ~g1g), though chromium (as high as 1,530~g1g) and mercury (as high as 2,000 ~g1g) were highest at some locations.

· Previous soil gas sampling found VOC contamination on west and north sides of Building 1-03-05and discontinuous area to east at three to seven foot depths. maximum concentrations of 18,037~gJkg total VOC. Harza found small concentrations of substituted benzene compounds in soilsamples at four to six foot depths in Tank Farm area (Harza 1997a).

Line 2 • RI soil analyses showed contamination in loess and fill material surrounding fonner wastewatersumps, wastewater discharge locations and drainageways. Explosives identified in surficial soilsnear foundations of munitions processing building and loading/unloading areas.

· Previous soil gas sampling indicated VOCs np to 1,950 ~gJkg near east and south sides of Building2-03, depths from ten to 27 feet, and VOCs up to 1,760 ~gJkg at five foot depths on the southeastside ofbuilding 2-02. Harza investigation identified small concentrations of ethyl benzene andxylenes in soils at Building 2-03 and ofcWorobenzene, 1,2-dicWorobenzene, and 1,4-dichlorobenzene in soils at Building 2-02.

Line 3 · RI indicated 38 of 135 surface soil samples contained explosives. Explosives concentrationsdecreased with depth and distance from most impacted soils. Soils with highest concentrations ofexplosives are located at wastewater sumps, foundations ofbuildings where wastewater isgenerated and loading docks. Swales and ditches tends to channelize concentrations in near-surfacesoils.

· Elevated metals levels more widespread at Line 3 than explosives levels. Metals not concentratedat a particular building. Majority of metal contamination is lead. Chromium found to lesser degreeat north end of the load line near Building 3-0 I, load line storage. Total metal concentrationsdecreased significantly with depth and as distance from the most impacted soils increased. Arealextent of impacted soils is generally within 10 - 20 feet ofhistorical sources.

· Previous soil gas sampling indicated presence ofVOCs up to 1,462 ~gJkg inunediately adjacent tothe north, east and south sides of Building 3-03. Harza investigation (1997a) shows VOCs of 16 to98 ~gJkg from samples, mostly at five foot depths. Highest detection was 215 ~gJkg at nine feet.



Table 4-4. Soil Contamination in Brush Creek Watershed

Facility Soil and Soil Gas Sampling Re.ult.

Line4A · Explosives contamination minimal.

· All 69 samples from the RI reported arsenic, bariwn, and lead at levels up to II; 526; and 1,160mglkg, respectively. Chromiwn detected in 64 samples at levels up to 39.8 mglkg and mercurydetected in 12 samples at levels up to 0.184 mglkg. Results indicate some surficial metalscontamination around the Building 4A-22-5 swnp and along the surface water drainage pathwayleading east of the site. Contamination around swnp limited to radius of 5 feet from the swnp anddepth ofless than one foot.

Line 5A · Explosives contamination of soils detected to depth of four feet in samples inunediately adjacent toswnps; concentrations decreased rapidly with depth.

Line 6 • Low levels of explosives detected during R1.• Elevated lead, silver and mercury levels at sumps, ditches and drainage swales with values as high

as 13,000; 500; and 1900 ~g1g, respectively. Generally, at-depth sample contaminant levels weresignificantly lower than corresponding surface samples.

Line 7 • Contamination by explosives and metals at low levels and confmed to depth of one foot.

Line 9 · Residua11evels of explosives in sump excavations area.

· Metals contamination, antimony, lead, and copper, localized around the sump excavations and indrainage pathways up to depths of one foot bgs.

· Previous soil gas sampling indicated VOC contamination east of Building 9-57 and south and westofnorthwest comer generally at depths of five to seven feet, but also up to 78 feet deep. Harzainvestigation recorded elevated PID headspace measurements ranging from 3.5 to 58 ~g1g from 13to about 35 feet in five borings and possible product was observed in some soils and cuttings.Analytical results identified 1,1,2-tricWorofluoroethane (Freon) in most soil samples withconcentrations up to 9,000 mglkg, with highest concentrations located east of Building 9-57.Vertically, Freon contamination between 23 to 33 foot depths, or less.

Line 800 · RI found explosives contamination most serious adjacent to sumps. Soil contamination limited todepths of less than two feet. Two areas contained explosives RDX (7.7 to 130 mglkg), HMX (4.3 to56 mglkg), and 2,4,6-lNT (2.3 to 36 mglkg). Explosives identified in drainage to Brush Creek andPink Water Lagoon.

· All 60 samples collected during RI contained bariwn and lead with maximum values of 651 and1650 mglkg, respectively. Chromium was detected in 59 samples with a maximwn value of 161mglkg, arsenic was detected in 56 samples with a maximum value of 18 mg/kg, mercury wasdetected in 20 samples with a maximwn value of7.8 mglkg, and cadmiwn was detected in tensamples with a maximwn value of757 mglkg.

Pesticide • Pesticides detected in 13 of 18 soil samples during RI. Pesticide with highest reported value wasPit 4,4'-DDE with levels ranging from 0.013 to 21,000 mglkg. Surficial contamination moving

southeast ofpit; subsurface contamination limited to area inside fence.

· SVOCs detected, highest was 2-methylnaphthalene at 200 mglkg.

Sewage · Metals reported in sludge, at expected levels.TreatmentPlant

4.1.6.2 Surface Water and Sediments. During 1997, surface water and sediments were sampled from

nine locations along Brush Creek, labeled 7E through 7M (Harza 1997a). Sampling sites are shown in Exhibit

4-2. Locations 7E and 7F, the upstrearnmost sample location drain parts of Lines 2 and 3, and are

domlStream from Line I. Total explosives concentrations of 32.3 and 10.2 !tg/L, respectively, were detected



in the surface water samples. No explosives were detected in one of the sediment sampling locations at 7E at

either the one foot or three foot depths. However, total explosives between 310 and 470 I!g/kg were detected

from the one foot depth at the second 7E location and both locations at 7F. Based on these results, surface

water in Brush Creek is being moderately contaminated by Lines I, 2, and/or 3. Residual explosives also are

present in shallow sediments, at least sporadically, although deeper sediments do not appear affected.

Location 7G is on a small tributary to Brush Creek, entering from the west just south of Line 3, and drains the

south portions of Line 3 and Lines 7 and 9. No explosives were detected in either surface water or sediment

at this location. TIris tributary drainage does not appear to contribute to contamination entering Brush Creek.

Location 7H is on a small tributary entering Brush Creek from the west and draining eastern parts of Line 800.

Explosives totaling 4.6 1!g!L were detected in the surface water sample and 330 I!g/kg in one of two sediment

samples. No explosives were detected at the other sediment location, either at the one or three foot depth. This

tributary contaminates Brush Creek, probably from Line 800. However, contributions appear minor, and

sediment impacts may be sporadic.

Locations 7I and 7J are on Brush Creek downstream from Line 2. Small concentrations of explosives were

detected in surface water at these locations, totaling 5.2 and 6.8 I!g/L, respectively. However, significant

explosives concentrations were detected in shallow (one foot) sediment samples. Total explosives

concentrations from two shallow sediment samples at 71 were 28,900 I!g/kg and 460 I!g/kg and at 7J were

1,890 and 4,490 I!g/kg. Sediment samples from the three foot depth at both locations were below the method

detection limit (MOL) for explosives. Based on these results, significant residual contamination is indicated

to be present in sediments, at least locally, along this reach of Brush Creek. Contamination appears limited

to the shallow zone and may be variable laterally. Surface water impacts, although present, appear minor

compared to sediments and may reflect NPDES discharges, contaminated groundwater inflows, or

remobilization of contaminants from the sediment.

Locations 7K, 7L, and 7M are on Brush Creek spanning the downstream portion ofthe lAAAP. 7L and 7M

are outside the plant boundary and 7K is at the "K" Road bridge. At each location, trace explosive

concentrations were detected in surface water, ranging from 2.67 1!g!L at 7K to 7.9 I!g/L at the others.

However, no explosives were detected in any ofthe sediment samples. Based on the absence ofcontaminants

in sediment, small concentrations of explosives in the surface water are likely due to surface water flow from



upstream rather than any local source and could be due either to plant discharges or sediment contamination

further upstream.

Surface Water. Results of surface water sampling during sununer, 1997 are reported in Table 4-5 (Harza,

I997a). Surface water sampled along Brush Creek contained the explosive chemicals RDX and HMX at eight

ofnine sampling locations, including downstream off-site locations. VOCs and SVOCs were not detected, and

metals detected did not exceed Iowa chronic water quality standards (wQS) for limited resource waters for

metals in surface water (Harza 1997a). Appendix A contains the actual WQS.

J - Estnnated value below the quantitatlon llID1t. B Detected m blank as well as sample. NA - Not analyzed.

Table 4-5. Results of Sunaee Water Sampling along Brosh Creek (June, 1997)

Sampling Location VOCs ("gIL) SVOCs Explosives (~) Metals Exceeding WQS (mglL)

7E Methylene cWoride (4.5B) None RDX (9.3); HMX (23) None

7F Methylene cWoride None RDX (5.2); HMX (5) None

(l2.4B)

7G Methylene chloride None None None

(J 1.6B)

7H Methylene cWoride None RDX (3); HMX (1.6) None

(l1.7B)

71 Methylene chloride None RDX (3.4); HMX (1.9) None

(IO.4B)

7J Methylene cWoride None RDX (5.3); HMX (1.6) None

(l1.3B)

7K Methylene cWoride (8.8B) None RDX (I.7); HMX None

(0.97J)

7L None None RDX (6.2); HMX (1.7) None

1M None None RDX (6.2); HMX (1.7) None- -

Sediment. The most recent sediment testing results along Brush Creek are reported below (Table 4-6).

Sediment from Brush Creek contains explosive contamination in eight of 27 samples. Although RDX was the

sole explosive detected in most sediment samples, HMX and 4-arnino-2,6-dinitrotoluene were present in

samples 711 and 7JI (downstream from Lines 1,2, and 3), and in addition 2,4,6-trinitrotoluene, 2,4

dinitrotoluene and 2-arnino-4,6-dinitrotoluene were also present in sample 71 I. Concentrations are highest in

the middle reaches of the Creek within IAAAP, particularly just downstream from Lines 2 and 3. No

explosives were detected in sediment in stream reaches within or downstream of the IAAAP. Explosives

contamination, where present, is prevalent in the near-surfuce sediments rather than deeper sediments. Toluene

was detected at three of the 26 sampling locations. SVOCs were detected at two sample locations.

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Final}


Phenanthrene, anthracene, pyrene, benzo(a)anthracene, chrysene, and benzo(a)pyrene were present in sample

71 and 4-methylphenol was present in sample 7L. Arsenic was encountered at concentrations which exceeded

the sediment Ecotox threshold level of 8.2 mglkg in six out of 26 sediment samples along Brush Creek.

Cadmium exceeded the Ecotox threshold of 1.2 mglkg in one sample. A full listing of the Ecotox criteria are

reprinted in Appendix A.

Table 4-6. Results of Sediment Sampling along Brush Creek

Sampling VOCs SVOCs Explosives Metals> EcotoxLocation ("glkg) (J1gIkg) (J1gIl<g) Thresholds (mgll<g)

7EI (I ft) Methylene chloride None None Arsenic (30.8)(7.9B)

7El (3 tt) NA NA None None

7E2 (I tt) NA NA RDX (470J) Arsenic (14.4)

7FI (I tt) Methylene chloride None RDX(400J) Arsenic (11.4)(8.3B)

7F2 (I tt) NA NA RDX (3IOJ) Arsenic (9.5)

7GI (I tt) Methylene chloride (8.7) None None None

7G2 (I tt) None None None Arsenic (8.8)

7HI (1 tt) Methylene chloride None None Cadmium (1.3)(l8.8B)

?HI (3 tt) NA NA None None

7H2 (I tt) NA NA RDX (330J) None

711 (I tt) Methylene chloride Phenanthrene (64.3J); RDX (9,900); HMX None(7.2B) Anthracene (64.9J); (1,900); 2,4,6-

Pyrene (I 39J); Trinitrotolnene (7,300); 2,4-Benzo(a)anthracene Dinitrotoluene (800J); 4-(47.8J); Chrysene Amino-2,6~Dinitrotoluene

(57.2J); (2,000); 2-Arnino-4,6-Benzo(a)pyrene (64.6J) Dinitrotoluene (7,000)

711 (3 tt) NA NA None None

712 (1 tt) NA NA RDX (460J) None

7JI (I tt) Methylene chloride None RDX (470J); HMX (760J); None(16.7B) 4-Amino-2,6-Dinitrotoluene

(660J)

7JI (3 tt) NA NA None None

7J2 (I tt) NA NA RDX (460J) Arsenic (13.8)

7KI (I tt) Methylene chloride None None None(l3.3B); Toluene (2.8J)

7KI (3 tt) NA NA None None

7K2 (I tt) NA NA None None

7LI (I tt) Methylene chloride 4-Methylphenol (62.1 J) None None(6JB); Toluene (3. IJ)

7LI (I tt) NA NA None None

7L2 (2.7 tt) NA NA None None



Table 4-6. Results of Sediment Sampling along Brush Creek

Sampling voe, svoe, Explosives Metals> EcotoJ:Location (J1g!kg) (J1g!kg) (Ilg!kg) Thre,hold, (mg/kg)

7MI (I tt) Methylene cWoride None None None(9.5B); Toluene (2.8J)

7Ml (3 tt) NA NA None None

7Ml (4.5 tt) NA NA None None

7M2 (2.7 tt) NA NA None None- -J - Estimated value below the quanlllallon lurut. B - Detected In blank as well as sample. NA - Not analyzed.

Source: Harza 1997

4.1.6.3 Groundwater. Table 4-7 is a matrix summarizing which COECs have been detected in

groundwater samples during the RI and/or the Supplemental RI (SRI) in the Brush Creek Watershed.

Table 4-7. Contaminants of Concern Detected in Groundwater

Location Metals Explo,ive, voe, svoe, Pesticides

Line I X X X X

Line 2 x x x

Line 3 x x x

Line4A x

Line SA x

Line 6 x

Line?

Line 9 x x

Line 800 x x x x

Pesticide Pit x x x

Sewage TreatmentPlant

Brush Creek is recharged by groundwater from both the east and west. Significant groundwater contamination

by explosives is present in Line 2 limited laterally to a small area in the center of Line 2, near the production

facilities and to the shallow drift unit in which most wells are screened. Total explosives concentrations in

excess of 1,000 Ilg/L are present in several wells in the area. Lateral migration has occurred to the west and

south, toward Brush Creek (Harza 1997a). Previous investigations indicated low levels of explosives

contamination in three of 19 monitoring wells in the Line I area at concentrations of 38.9,3.22,3.41 Ilg/L


March 20, 1998Page 4-10

total explosives, the first in a shallow well, the second in a bedrock well within the Line I boundary, and the

third in a shallow well outside and southwest ofthe Line I boundary, respectively (JAYCOR 1996).

Significant concentrations ofexplosives (1 ,833 ~g/L total explosives) were detected in groundwater in one well

in the Line 3 area, with trace concentrations in nearby wells. Levels of explosives in wells downgradient from

this area to the east, southeast and northeast were below detection limits. Groundwater contamination at Line

3 appears to be a localized problem with little lateral migration (Harza I 997a).

Significant levels ofexplosives were reported in the Line 800 and Pink Water Lagoon areas. Three wells in

the area reported total explosives at 18108, 12370, and 11789 ~g/L. RDX was reported at levels as high as

13,000 ~gIL; HMX at 1,700; 1,3,5-trinitrobenzene at 2,600 ~g1L; and 2,4,6-trinitrotoluene at 2200 ~gIL.

4.1.6.4 NPDES Discharges. NPDES (National Pollutant Discharge Elimination System) permitted

discharges are an ongoing avenue for the entry of explosives and metals into Brush Creek. State mandated

monitoring ofcertain parameters provide information about the quantity ofthe contaminants entering the creek

via this route. The NPDES-permitted outfalls in the Brush Creek basin, not all of which are currently

operating, are listed in Table 4-8.

Table 4-8. Currently Permitted NPDES Dischar es to Brush Creek

NPDES Location Remarks Monitoring ParametersOutfall No.

082 Bldg 800-70-1 Discharge from explosive Flow, Total Suspended Solids, pH,loading operations at Line 800 TNT. RDX+HMX

OIl Bldg 500-139 Treated emuent from main Flow, Total Suspended Solids, pH,heating plant TNT, RDX+HMX

012 Bldg 1-70-1 Discharge from explosive Flow, TSS, pH, TNT,loading operations at Line 1 RDX+HMX, Acute Toxicity-

Ceriodaphnia & Pimephales

013 Bldg 500-216-1 Main sewage treatment plant Flow, CBOD" Ammonia Nitrogen,Temperature, TSS, Ag, pH, SettleableSolids, Acute Toxicity - Ceriodaphnia& Pimephales

021 Bldg 2-70-1 Discharge from explosive Flow, TSS, pH, TNT, RDX+HMXloading operations at Line 2

022 Bldg 2-70-2 Discharge from explosive Flow, TSS, pH, TNT, RDX+HMXloading ooerations at Line 2



051 Bldg 5A-140-3 Discharge from explosive Flow, TSS, pH, TNT, RDX+HMXloading operations at Line SA


March 20, 1998Page 4-11

Discharge has not been continuous from some of the outfalls, and NPDES Outfall No. 51 has not been

operating since 1989 (possibly earlier). The pennitted effluent limitations for the outfall parameters are listed

in Table 4-9.

Table 4-9. NPDES Emuent Limitations for the JAAAP

Concentration MassWastewater Season Average AverageParameters

7Dav 30Dav Daily Max. Units 7Dav 30Dav Daily Max. Units

Flow Yearly 0.093 MGD0.49(13) 1.08(13)

Total Suspended Yearly 20.00 40.00 mgIL 16.00 31.00 lbs/daySolids 164.00(13) 103.00(13)

pH Yearly 6.00 9.00 SID

Trinitrotoluene Yearly 0.33 1.00 mgIL 0.26 0.77 lbs/day

RDX+HMX Yearly 0.75 2.20 mgIL 0.58 1.75 lbs/day

Acute Toxicity, Yearly 1.00 NonCeriodaphnia toxic

Acute Toxicity, Yearly 1.00 NonPimephales toxic

CBOD5 Yearly 40.00 25.00 mgIL 164.00 103.00 lbs/day

Ammonia Jan - 6.70 11.00 mgIL 58.00 95.00 lbs/dayNitrogen (N) Feb

Ammonia March- 3.00 5.00 mgIL 26.00 44.00 lbs/dayNitrogen (N) June,

Sept -Dec

Ammonia Jul- 2.80 4.60 mgIL 24.00 40.00 Ibs/dayNitrogen (N) Aug

Silver, Total (as Yearly 0.009 0.016 mgIL 66.00 110.00 0.001Ag) Ibs/day

Based on yearly average flows and explosives concentrations, mass loadings due to NPDES wastewater

discharges were calculated for each stretch ofBrush Creek (Harza 1997a). These calculated loadings for each

stretch ofthe creek were used to detennine in-stream concentrations of explosives, based on typical dry weather

stream flow. Table 4-10 compares the calculated average contaminant loadings to Brush Creek for the years

1989 through March of 1997 to grab samples collected in May 1997. Sample locations are shown in Exhibit

4-2.

Table 4-10. Explosives Concentrations in Brush Creek Surface Water

Location Sample Sample Concentration (llglL) Calculated Concentration (llg/L)

DRoad 7E 32.3 7.94


March 20, 1998Page 4·12

Table 4-10. Explosives Concentrations in Brosb Creek Surface Water

Location Sample Sample Concentration (llglL) Calculated Concentration <Ilg/L)

I Road 7F 10.2 12.307H 4.6

HRoad 71 5.3 2.7271 6R

KRoad 7K 2.67 0.887L 7.97M 7Q

Line I (including Outfall 12) and Line 5 are in the stretch of Brush Creek upstream of D-Road, Line 2

(including Outfalls 21 and 22) and Line 3 (including Outfalls 32 and 33) are upstream of I-Road, Line 800 is

upstream of H Road, and the sewage plant is upstream of K Road. The table indicates surface water

contamination due to NPDES permitted discharges from Line I and/or Line 5, increased contamination from

Lines 2 and 3, and decreased contamination downstream.

The data indicate that the middle reaches of the creek are the most contaminated and the downstream reach is

the least contaminated. Groundwater recharge to the creek dilutes the upstream contaminants and does not add

significant contaminant concentrations.

4.2 Results of Field Sampling

Aquatic macroinvertebrates, fish, soils, and small manunals were collected at several locations in the Brush

Creek watershed to assess ecological stress due to past and ongoing operations ofthe lAAAP. Sampling was

planned to assess risk over a gradient of contamination, ranging from reference (or control) unimpacted areas,

to those areas assumed to be at risk. While the greatest contamination by explosive chemicals is around Line

I and Line 800 pinkwater lagoon, these sites are currently being remediated.

4.2.1 Aquatic Macroinvertebrates

Sampling methods for aquatic macroinvertebrates are discussed in Section 3.8 and in the WQAPP (Harza

1997b). Benthic sampling stations along Brush Creek yielded 137 to 294 individuals and 8 to 17

macroinvertebrate taxa at each site. The number collected by station and the Hilsenhoff Biotic Index (HEI)

tolerance values for all taxa are presented in Appendix F. Pollution tolerance values, as used in the Rapid


March 20, 1998Page 4-13

Bioassessment technique, are provided by Hilsenhoff (1988). The greatest number of taxa were collected at

reference Station BC9 (13 taxa) and offsite station BC8 (17 taxa) downstream of IAAAP. Taxa that

accounted for most of the collected total were:

hydropsychid caddis fly nymphs 37%

asellid isopods 20%

chironomid midge larvae 15%

black fly larvae 12%

baetid mayfly nymphs 5%

These taxa are moderately tolerant ofpollution. HEr tolerance values vary from 0 (intolerant, sensitive) to 10

(highly tolerant). Except for asellid isopods (that have a tolerance value of 8), the above taxa have tolerance

values of 4 to 6.

4.2.2 Fish

Fantail darters were caught in each of the three sampling locations in Brush Creek. The fish tissue analyses

indicated no evidence that aquatic biota are accumulating explosives in Brush Creek. All analyses of

explosives in fish tissue were non-detects (Table 4-11). MDLs are indicated in Table 4-11 as being less than

the stated concentration.

4-11. Explosives Contamination in Fish in Brush Creek

Station BC5 BC6 BC8

Field ID BC5-F BC6-F BC8-F

Lab ID 5000-14 5000-18 5000-12

SDecies Fantail Fantail Fantail

Analvte (ul!!kJ! wet wei' htl

1,3,5-Trinitrobenzene <312 <312 <312

1,3-Dinitrobenzene <295 <295 <295

2,4,6·Trinitrotoluene <314 <314 <314

2,4-Dinitrotoluene <316 <316 <316


2-Amin04,6-Dinitrotoluene <263 <263 <263

2-Nitrotoluene <291 <291 <291


4-Amino-2,6.Dinitrotoluene <283 <283 <283


RDX <273 <273 <273


March 20, 1998Page 4·14

4-11. Explosives Contamination in Fish in Brosh Creek

Station BCS BC6 BC8

Field ID BCS-F BC6-F BC8-F

LabID SOOO-I4 SOOO-18 5000-12Species Fantail Fantail Fantail

AnaMe lul!!kl! wet wei btl

Nitrobenzene <329 <329 <329

HMX <285 <285 <285TellYl <286 <286 <286

Analyses of mercury in darters from Brush Creek also indicated no significant uptake (Table 4-12). For

comparison, the Food and Drug Administration (FDA) limit for human consumption ofmercury is one mgIkg.

Levels ofmercury in darters from Brush Creek were well below that limit.

Table 4-12. Metal Contamination in Fish in Brosh Creek

Station BCS BC6 BC8

Field ID BCS-F BC6-F BC8-F

LabID SOOO-14 SOOO-18 SOOO-12

Specie. Fantail Fantail Fantail

Analvte Ime/kl! wet weiehtl

Mercurv 017 I 0.25 I 0.12

Except for dieldrin in sample BC8, no pesticides were found above MDLs in Brush Creek fish. Slation BC8

is offsite, located downstream of the southern boundary of the IAAAP property. The isolated presence of

dieldrin at BC8 suggests a local agricultural source ofthe pesticide. No uptake ofpesticideslPCBs in Brush

Creek attribulable to IAAAP operations is evidenced based on the analytical results (Table 4-13).

Table 4-13. Pesticide Contamination in Fish in Brosh Creek

Station BCS BC6 BC8

Field ID BCS·F BC6-F BC8-F

LahID SOOO-14 SOOO-18 SOOO-12

Snecies Fantail Fantail Fantail

AnaMe (u~/kt! wet weieht)

aipha-BHC <1.6 <1.6 <1.6

beta-BHC <1.5 <1.5 <1.5

delta-BHC <1.6 <1.6 <1.6

2amma-BHC <1.6 <1.6 <1.6

Heptachlor <1.6 <1.6 <1.6

Aldrin <1.6 <1.6 <1.6

Heptachlor eooxide <1.7 <1.7 <1.7

Endosulfan I <1.7 <1.7 <1.7

Dieldrin <1.6 <1.6 8.844'·DDE <1.7 <1.7 <1.7


March 20, 1998Page 4-15

Table 4-13. Pesticide Contamination in Fish in Brush Creek

Station BC5 BC6 BC8Field ID BC5-F BC6-F BC8-FLab ID 5000-14 5000-18 5000-12Specie, Fantail Fantail Fantail

Analvte (Ul!ikl! wet wei~ht

Endrin <1.6 <1.6 <1.6

Endosulfan IT <1.6 <1.6 <1.6

4,4'-DDD <1.7 <1.7 <1.7

Endosulfan sulfate <1.6 <1.6 <1.6

44'-DDT <1.6 <1.6 <1.6

Methoxvchlor <1.7 <1.7 <1.7

Endrin a1dehvde <1.7 <1.7 <1.7

Chlordane <3.3 <3.3 <3.3

Toxaphene <33.0 <33.0 <33.0

Arochlor 1016 <16.7 <16.7 <16.7

Arochlor 1221 <27.2 <27.2 <27.2

Arochlor 1232 <15.8 <15.8 <15.8

Arochlor 1242 <16.7 <16.7 <16.7

Arochlor 1248 <16.5 <16.5 <16.5

Arochlor 1254 <16.2 <16.2 <16.2

Arochlor 1260 <16.4 <16.4 <16.4

Endrin ketone <1.7 <1.7 <1.7

4.2.3 Small Mammals

Mamrna1 tissues were obtained at four ofthe five sampling locations in the Brush Creek watershed utilized to

assess the risk to the viability of wildlife populations (Table 4-14). The white-footed mouse (Peromyscus

ieucopus) was the most common species caught at these trapping locations. However, because there was

insufficient mouse tissue for all analyses, the meadow vole (Microtus pennsyivanicus) and the short-tailed

shrew (Blarina brevicauda) were also analyzed from this watershed. Weights shown in Table 4-14 are field

weights ofwet animals, and concentrations in the succeeding table are on a wet weight basis.

Table 4-14. Small Mammals from Brush Creek Watershed Analyzed for Selected COECs

Site nate Snecies Wei~ht (~) Lab Id Parameters

BC10 7/21/97 Peromvscus [eucoDus 16 1094 H. Pb Th A. Cr Explosives

BC3 7/21/97 Blarina brevicauda 24 1088 H2. Pb Th A2. Cr Exolosives

BC3 7/25/97 Microtus nennwlvanicus 46 1155 H. Pb Th A. Cr Explosives PestIPCBs

BC3 7/21/97 Peromvscus leucorJus 24 1092 H2. Pb Th A2. Cr Exolosives

BC6 7/19/97 Blan'no brevicauda 24 1093 H. Pb. Th A. Cr Explosives

BC6 7/24/97 Peromvscus JeucoDus 34 1160 H2. Pb Th A2. Cr Exnlosives

BC6 7/19/97 Microtus nennwJvanicus 68 1102 H. Pb Th A2. Cr Explosives PestIPCBs


March 20, 1998Page 4~16

Table 4-14. Small Mammals from Brosh Creek Watershed Analyzed for Selected COECs

S'te Date Snecies Weiaht {a,l Lab Id ParametersBC9 7/22/97 Microtus "enn ....'!van;cus 52 1095 H. Pb Th A. Cr Exnlosives PestIPCBsBC9 711 9/97 PeromtJscus leuconus 46 1090 Hn Pb Th An Cr Exnlosives PestlPCBsBC9 7/20/97 Peromvscus leuconus 64 1100 Hn Pb Th An Cr Exnlosives PestlPCBs

Minor accumulations ofRDX, nitrobenzene, 2-arnin0-4,6-dinitrotoluene and chromium were found in mammal

tissue (Tables 4-15 through 4-17). Mammals captured at BC9, a reference station upstream of all IAAAP

production facilities showed minor residues ofRDX, nitrobenzene, 2-amino-4,6-dinitrotoluene and chromium.

This could be due to errors in assumptions regarding home range size or contamination. Soils from BC9 do

not show these explosives. Similar levels of RDX were found in small mammals captured at the "impacted"

stations. However, with the exception of a mouse taken at BC6 with low levels ofnitrobenzene residue, no

other explosives were found above MDLs in the tissues ofmammals captured at any ofthe "impacted" stations.

Table 4-15. Explosives Contamination in Small Mammals/Brush Creek Watershed

Station BC9 BC9 BC9 BC10 BC3 BC3 BC3 BC6 BC6 BC6Field ID 1090 1100 1095 1094 1092 1155 1088 1160 1102 1093LabID 5002-04 5002-05 5002-06 5002-03 5002-01 5002-16 5002-02 5003-01 5002-07 5002-08Snecies Mouse Mouse Vole Mouse Mouse Vole Shrew Mouse Vole Shrew

Analvte (u.;;k;wet wei.ht1,3,5-Trinitrobenzene <312 <312 <312 <312 <312 <312 <312 <312 <312 <3121,3-Dinitrobenzene <295 <295 <295 <295 <295 <295 <295 <295 <295 <2952,4,6-Trinitrotoluene <314 <314 <314 <314 <314 <314 <314 <314 <314 <3142.4-Dinitrotoluene <316 <316 <316 <316 <316 <316 <316 <316 <316 <3162,6.Dinitrotoluene <288 <288 <288 <288 <288 <288 <288 <288 <288 <2882-Amin04,6-Dinitrotoluene <263 <263 2700 <263 <263 <263 <263 <263 <263 <2632-Nitrotoluene <291 <291 <291 <291 <291 <291 <291 <291 <291 <2913-Nitrotoluene <342 <342 <342 <342 <342 <342 <342 <342 <342 <3424-Arnino-2,6.Dinitrotoluene <283 <283 <283 <283 <283 <283 <283 <283 <283 <2834-Nitrotoluene <269 <269 <269 <269 <269 <269 <269 <269 <269 <269RDX 3200 5500 1600 2000 870 <273 1600 3600 <273 <273Nitrobenzene <329 <329 2300 <329 <329 <329 <329 8100 <329 <329HMX <285 <285 <285 <285 <285 <285 <285 <285 <285 <285Teind <286 <286 <286 <286 <286 <286 <286 <286 <286 <286

Further, with the exception of aluminum, chromium, and iron, metal residues in mammal tissue were non

detects and within residue levels not expected to reflect adverse effects. Some mammals taken from the

"impacted" stations were slightly higher in chromium residue than the reference station, BC9. Interestingly,

voles contained lower concentrations of aluminum and iron than white-footed mice or short-tailed shrews.

While no literature values for aluminum residues in rodents were available, data on other metals were found.


March 20, 1998Page 4-17

The amounts ofiron and other metals in mammals from the Brush Creek watershed are consistently lower than

literature values. Dierenfield et al. (1996) analyzed adult captive house mice (Mus musculus domesticus) and

found 489 mg/kg iron (wet weight) in whole mice. Sawicki-Kapusta et al. (J 987) analyzed metals in wild

rodents from polluted and unpolluted Polish forests. In an unpolluted forest, they found yellow-necked field

mice (Apodemus jlavicollts) averaged 838 mg Felkg and bank voles (Clethrionomys glariolus) averaged 905

mg FeIkg (estimated as wet weight). Interestingly, Sawicki-Kapusta et al. found no significant differences in

tissue iron levels in rodents captured in polluted forests from those captured in unpolluted forests. Wlostowski

et al. (1988) also analyzed metals in wild bank voles captured in Poland. Using their data, we estimated whole

bank voles to average 681 mg Fe/kg (wet weight). In contrast to their observations of iron residue regulation

in mammals, Sawicki-Kapusta et al. (1987) found lead levels in yellow-necked field mice to average 0.03

mglkg and to average 7.3 mglkg in bank voles, with statistically significant differences in rodent tissue lead

residues in polluted and unpolluted forests.

Table 4-16. Metal Contamination in Small MammalslBrush Creek Watershed

Station BC9 BC9 BC9 BCIO BC3 BC3 BC3 BC6 BC6 BC6

Field In 1090 1100 1095 1094 1092 1155 1088 1160 1102 1093

Lab In 5002-04 5002-05 5002-06 5002-03 5002-01 5002-16 5002-02 5003-01 5002-07 5002-08

Suecies Mouse Mouse Vole Mouse Mouse Vole Shrew Mouse Vole Shrew

Analvle (mel"" weI weiehl

Aluminum 72.7 58.9 13.2 55.7 788 7.8 184 57.1 22.6 35.8

Chromium 0.59 <0.50 <0.50 069 0.92 <0.50 0.94 0.82 0.76 <0.50

Iron 231 194 113 267 243 81 644 248 174 233

Lead <2.5 <2.5 <2.5 <2.5 <2.5 <2.5 <2.5 <2.5 <2.5 <2.5

Mercurv <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10 <0.10

Silver <0.50 <0.50 <0.50 <0.50 <0.50 <0.50 <0.50 <0.50 <0.50 <0.50

Thallium <3.0 <3.0 <3.0 <3.0 <3.0 <3.0 <3.0 <3.0 <3.0 <3.0

Pesticide and PCB residues in mammals from all stations were non-detects (Table 4-17).

Table 4-17. Pesticide Contamination in Small Mammals/Brush Creek Watershed

Station BC9 BC9 BC9 BC3 BC6

Field ID 1090 1100 1095 1155 1102

LablD 5002-04 5002-05 5002-06 5002-16 5002-07

Species Mouse Mouse Vole Vole Vole

Analvte (II /kg wet wei ht)

alpha-BHC <1.6 <1.6 <1.6 <1.6 <1.6

beta-BHC <1.5 <1.5 <1.5 <1.5 <1.5

delta-BHC <1.6 <1.6 <1.6 <1.6 <1.6

Iowa Anny Ammunition PlantEcological Risk Assessment Addendum (Draft Final)

March 20, 1998Page 4-18

Table 4-17. Pesticide Contamination in Small Mammals/Brush Creek Watershed

Station BC9 BC9 BC9 BC3 BC6Field ID 1090 1100 1095 1155 1102LabID 5002-04 5002-05 5002-06 5002-16 5002-07Species Mouse Mouse Vole Vole Vole

Analyte (u2/kl! wet wei htl

Igamma-BHC <1.6 <1.6 <1.6 <1.6 <1.6Heptachlor <1.6 <1.6 <1.6 <1.6 <1.6Aldrin <1.6 <1.6 <1.6 <1.6 <1.6Heptachlor epoxide <1.7 <1.7 <1.7 <1.7 <1.7Endosulfan I <1.7 <1.7 <1.7 <1.7 <1.7

Oieldrin <1.6 <1.6 <1.6 <1.6 <1.64,4'-00E <1.7 <1.7 <1.7 <1.7 <1.7Endrin <1.6 <1.6 <1.6 <1.6 <1.6Endosulfan II <1.6 <1.6 <1.6 <1.6 <1.64,4'-000 <1.7 <1.7 <1.7 <1.7 <1.7

Endosulfan sulfate <1.6 <1.6 <1.6 <1.6 <1.6

4,4'-00T <1.6 <1.6 <1.6 <1.6 <1.6

Methoxychlor <1.7 <1.7 <1.7 <1.7 <1.7

Endrin aldehvde <1.7 <1.7 <1.7 <1.7 <1.7

Chlordane <3.3 <3.3 <3.3 <3.3 <3.3

Toxaphene <33.0 <33.0 <33.0 <33.0 <33.0

Arochlor 1016 <16.7 <16.7 <16.7 <16.7 <16.7

Arochlor 1221 <27.2 <27.2 <27.2 <27.2 <27.2

Arochlor 1232 <15.8 <15.8 <15.8 <15.8 <15.8

Arochlor 1242 <16.7 <16.7 <16.7 <16.7 <16.7

Arochlor 1248 <16.5 <16.5 <16.5 <16.5 <16.5

Arochlor 1254 <16.2 <16.2 <16.2 <16.2 <16.2

Arochlor 1260 <16.4 <16.4 <16.4 <16.4 <16.4

Endrin ketone <1.7 <1.7 <1.7 <1.7 <1.7

4.2.4 Soils

Surface soil samples were collected for analysis from the same four sites where small mammals were captured

for tissue analysis. The background sample (BC9) showed no measurable explosives, pesticides or PCBs. In

soils from the three sites, minor concentrations of 2,4,6-trinitrotoluene; 2-arnino-4,6-dinitrotoluene; RDX;


March 20, 1998Page 4~19

HMX; chromium, lead, and silver were detected. No pesticideslPCBs were reported above the MDLs. Results

are summarized in Tables 4-18 through 4-20).

Table 4-18. Explosives Contamination in SoiIlBrush Creek Watershed

Station BC9 BC9 BCIO BC3 BC6

Field ID BC9-S BC9-S-DUP BCIO-S BC3-S BC6-S

Lab ID 5000-04 5000-02 5000-67 5000-66 5000-10

Analvte h",ikl! drv wei htl

I 3,5-Trinitrobenzene <312 <312 <312 <312 <312

1 3-Dinitrobenzene <295 <295 <295 <295 <295

24,6-Trinitroto1uene <314 <314 <314 1300 <314

2 4-Dinitroto1uene <316 <316 <316 <316 <316

2 6-Dinitroto1uene <288 <288 <288 <288 <288

2-Amin0-4,6-Dinitroto1uene <263 <263 <263 740 <263

2-Nitroto1uene <291 <291 <291 <291 <291

3-Nitroto1uene <342 <342 <342 <342 <342

4-Amino-2,6-Dinitroto1uene <283 <283 <283 420 <283

4-Nitrotoluene <269 <269 <269 <269 <269

RDX <273 <273 920 4700 <273

Nitrobenzene <329 <329 <329 <329 <329

HMX <285 <285 610 2300 <285

Tetrv1 <286 <286 <286 <286 <286

Table 4-19. Metals Contamination in Soil/Brush Creek Watershed

Station BC9 BC9 BClO BC3 BC6


LabID 5000-04 5000-02 5000-67 5000-06 5000-10

Analvte m~ikl! drv wei htl

Chromium 11.2 10.5 16.0 26.8 10.2

Lead 15.4 15.0 18.3 18.0 9.6

Mercury <0.12 <0.12 <0.12 <0.12 <0.12

Silver 0.79 0.77 1.2 2.8 2.1

Thallium <3.7 <3.7 <3.5 <3.6 <3.6

Table 4-20. Pesticide Contamination in Soil/Brosh Creek Watershed



Lab ID 5000-04 5000-02 5000-07 5000-06 5000-10

Analvte ""ikl! drv weiJ!btl

a1pha-BHC <0.67 I <0.68 <0.64 I <0.66 I <0.65

beta-BHC <0.63 I <0.64 <0.6 I <0.63 I <0.61


March 20, 1998Page 4-20

Table 4-20. Pesticide Contamination in SoiIIBrosh Creek Watershed


FIeld ID BC9-S BC9-S-DUP BCIO-S BC3-S BC6-S

LabID 5000-04 5000-02 5000-07 5000-06 5000-10

Analyte Ill!!kl>: dry weililit)

delta-BHC <0.67 <0.68 <0.63 <0.66 <0.64

gamma-BHC <0.64 <0.65 <0.61 <0.63 <0.62

Heptachlor <0.67 <0.69 <0.64 <0.67 <0.65

Aldrin <0.65 <0.66 <0.62 <0.64 <0.63

Heptachlor eooxide <0.68 <0.69 <0.65 <0.68 <0.66

Endosulfan I <0.68 <0.69 <0.65 <0.67 <0.66

Dieldrin <0.66 <0.67 <0.63 <0.65 <0.64

4,4'-DDE <0.68 <0.69 <0.65 <0.67 <0.66

Endrin <0.66 <0.67 <0.63 <0.66 <0.64

Endosulfan II <0.67 <0.68 <0.64 <0.66 <0.65

4,4'-DDD <0.68 <0.69 <0.65 <0.67 <0.66

Endosulfan sulfate <0.66 <0.67 <0.62 <0.65 <0.63

4,4'-DDT <0.64 <0.65 <0.61 <0.63 <0.62

MethoXYchlor <0.68 <0.69 <0.64 <0.67 <0.66

Endrin aldehyde <0.69 <0.7 <0.65 <0.68 <0.67

Chlordane <1.4 <1.4 <1.3 <1.3 <1.3

Toxaphene <13.5 <13.7 <12.9 <13.4 <13.1

Arochlor 1016 <6.8 <6.9 <6.5 <6.8 <6.6

Arochlor 122I <11.2 <11.3 <10.6 <11.0 <10.8

Arochlor 1232 <6.5 <6.6 <6.2 <6.4 <6.3

Arochlor 1242 <6.8 <6.9 <6.5 <6.8 <6.6

Arochlor 1248 <6.8 <6.9 <6.4 <6.7 <6.5

Arochlor 1254 <6.6 <6.7 <6.3 <6.6 <6.4

Arochlor 1260 <6.7 <6.8 <6.4 <6.7 <6.5

Endrin ketone <0.69 <0.7 <0.65 <0.68 <3.9

4.2.5 Water

Available infonnation on contaminants in surface water was limited to total pollutant concentrations. Surface

water was sampled on October 27, 1997 to speciate metals into dissolved and filtrable fractions (Table 4-21).

While aluminum and iron are largely present in particulate forms, barium and zinc are present largely in

dissolved form. None ofthe measurements ofmetals shown in Table 4-21 exceed the Iowa chronic or acute

water quality standards for limited resource waters.


March 20, 1998Page 4-21

Table 4-21. Speciation of Metals in Surface Water - Brush Creek Watershed (mgIL)

BC9 (reference) BC6 (Road K)

Metal Dissolved Total Dissolved Total

Aluminum <0.05 0.077 <0.05 0.45

Barium 0.045 0.044 0.076 0.077

Cobalt <0.005 <0.005 <0.005 <0.005

Iron <0.05 0.21 <0.05 0.7

Lead <0.025 <0.025 <0.025 <0.025

Manganese 0.032 0.037 0.03 0.043

Silver <0.005 <0.005 <0.005 <0.005

Thallium <0.03 <0.03 <0.03 <0.03

Vanadium <0.005 <0.005 <0.005 <0.005

Zinc 0.0098 0.0098 <0.005 0.0085

4.3 Risk Characterization

The ecological risk within the Brush Creek watershed is assessed separately for aquatic ecosytems and

terrestrial ecosystems. The above described data, from both Harza and JAYCOR databases, are used to

develop exposure scenarios for ecological receptors on the IAAAP property.

4.3.1 Aquatic Ecosystem

Aquatic assessment endpoints are the individual survival and viability ofthe state-listed threatened orangethroat

darter and the health ofthe benthic macroinvertebrate community. To assess the risk to the orangethroat darter,

the levels of COECs in the water colunm were compared to literature-based benchmarks, known as Reference

Toxicity Values (RTVs), for toxicological effects. As the selected RTVs are derived from multiple species

testing, the conclusions are relevant specifically to orangethroat darter and generally to all fishes. The health

ofthe aquatic benthic community was measured using the Rapid Bioassessment Protocol III developed by the

USEPA (Plafkin, et al. 1989).


March 20, 1998Page 4-22

4.3.1.1 Chemicals of Ecological Concern. The maximum and 95% upper confidence limit (VCL) total

concentrations of the preliminary aquatic COECs for the Brush Creek watershed are shown in Table 4-22,

derived as discussed in Chapter 3. Five explosives, fourteen metals, and two organic chemicals were identified

as preliminary COECs for the Brush Creek watershed. The values shown are for all samples within the

watershed, including "hot spots", such as sumps, not normally considered pathways. Therefore all potential

ecological exposure pathways should be implicitly considered.

Table 4-22. Aquatic COECs for Brush Creek Watershed

Contaminant Maximum ("gIL ) 95% UeL ("gIL)

1,3,5.trinitrobenzene 100 (S) 1.25 (S)

2,4,6-trinitrotoluene 270,000 (S) 8.1 (S)

HMX 28,000 (S) 22.9 (S)740 (W) 51.2 (W)

RDX 100,000 (S) 14.2 (S)5,400 (W) 248 (W)

Tetryl 12.5 (W) 1.79 (W)

Aluminum 210,000 (S) 12,637 (S)740,000 (W) 3,279 (W)

Barium 24,000 (S) 553 (S)996 (W) 132 (W)

Beryllium 2.6 (S) 1.17 (S)

Chromium 1,600 (W) 14.9 (W)

Cobalt 80 (S) 13.9 (S)

Iron 86,100 (S) 20,959 (S)2,500,000 (W) 4,932 (W)

Lead 660 (W) 21.6 (W)

Manganese 8,640 (S) 1,223 (S)19,000 (W) 306 (W)

Mercury (Biomagnifier) 5.9 (W) 0189 (W)

Selenium 2.9 (S) 0.64 (S)

Silver 2,130 (W) 10.5 (W)

Thallium 31.8 (S) 126 (S)

Vanadium 64.9 (S) 29.8 (S)

Zinc 1,580 (W) 157 (W)

Benzo[def]pbenanthrene 1.2 (S) 0.050 (S)

Chloromethane 8.7 (W) 1.9 (W)

W = Water S=Sediment


March 20, 1998Page 4·23

4.3.1.2 Exposure Estimation. Aquatic concentrations ofCOEC for exposure estimates were initially

taken as the 95% UCL ofall ofJAYCOR's surface water measurements in the watershed (Appendix B). This

estimates the central tendency ofthe COEC concentration and accounting for variability and uncertainties in

the accuracy ofthe measurements. In estimating the 95% UCL, nondetected concentrations were taken as 50%

ofthe MOL. The exposure concentrations in surface water are based on total metals analyses available from

JAYCOR analyses. Use oftotal metal concentrations results in considerable over prediction of exposure point

concentrations because only a fraction of total metals are bioavailable. Also, laboratory toxicity tests are

conducted under conditions favoring toxicant bioavailability; lab dilution waters contain low concentrations

ofsuspended solids and organic carbon. Standard test methods require high purity dilution water. Recognizing

this, dissolved COEC concentrations should be used in aquatic ecological risk assessments (WERF 1996).

Therefore, we obtained information on the fractions of total metals in surface water that were filtrable, an

operational definition for the dissolved fraction (see Table 4-21). Ten metals were speciated in this manner.

This allowed estimation ofexposure point concentrations as dissolved metals for these ten elements. For other

contituents, total concentrations (as the 95%UCL from JAYCOR's database) were used.

No biomagnifYing contaminants of concern are found in significant levels in darter tissue. Mercury was the

only COEC found in darter tissue slightly above the MDL.

4.3.1.3 Effects. Aquatic reference toxicity values (RTV) were taken from a variety of sources, including

Suter and Tsao (1996), Talmage and Opresko (1996a,b,c), Maxwell and Opresko (1996), Eisler (1987),

USACE (1996) and USEPA (1995). Table 4-23 provides the effects criteria of all COECs selected for the

lAAAP risk assessment. In general, National or Iowa water quality standards were not used for this risk

assessment, because those standards are designed to protect all uses and may be over or underprotective of

orangethroat darter survival. In most cases, Tier 11 Secondary Chronic Values (SCV), calculated by EPA or

Oak Ridge National Laboratory according to the Water Quality Guidance for the Great Lakes System, were

utilized. Tier 11 values are concentrations that wonld be expected to be higher than National Ambient Water

Quality Criteria in no more than 20% of cases. Tier 11 SCVs are comparable to the Final Chronic Values

(FCY) ofthe NAWQC, but were estimated from less data. Ifno Tier IT value was available, the lowest chronic

value from fish tests was used, as provided by Suter and Tsao (1996). These are typically the lowest chronic

toxicity value for fish reported in the literature.


March 20, 1998Page 4-24

Table 4.23. Aquatic Reference Toxicitv ValuesCOEC Criterion Concentration Units Reference

1,3,5-Trinitrobenzene Lowest chronic value· fish 120 uolL Talma.e and Onresko 1996

1,3-Dinitrobenzene Lowest chronic value. fish370 ~gIL

van der Schalie 1983 as cited inUSACE 1996

2,6-Dinitrotoluene CWS 620 uolL Assumed = 2,4-DNT

2,4.Dinitrotoluene CWS 620 uolL USEPA 1978

2,4,6-Trinitrotoluene ChronicWOC 130 u.n. Talma.e and Onresko 1996

Tetrvl 10% ofoicric acid NOAEL - fish 3000 ".n. Talmwe et al 1996

HMX Lowest chronic value - fish 3300 nolL Ma~"Well and Opresko 1996

RDX Lowest chronic value· fish 4900 nolL Talmage et all996

Aluminum Lowest chronic value - fish 3288 nolL Suter & Tsao 1996

Barium Tierll SCV 4 nolL Suter & Tsao 1996

Bervllium Lowest chronic value - fish 57 u.1L Suter & Tsao 1996

Chromium Lowest chronic value· fish 68 u.n. Suter & Tsao 1996

Cobalt Tier II SCV 23 u.n. Suter & Tsao 1996

Copper Lowest clu"onic value - fish 3.8 u./1. Suter & Tsao 1996

Iron Lowest chronic value - fish 1300 u./1. Suter & Tsao 1996

Lead Lowest chronic value· fish 18.88 nolL Suter & Tsao 1996

Manganese Tier II SCV 120 ~oIL Suter & Tsao 1996

Mercurv Tier II SCV· total H. 120 u.1L Suter & Tsao 1996

Selenium Lowest chronic value - fish 88.3 u.n. Suter & Tsao 1996

Silver Tier II SCV 0.36 u.n. Suter & Tsao 1996

Thallium Tier II SCV 12 u.n. Suter & Tsao 1996

Vanadium Tier II SCV 20 nolL Suter & Tsao 1996

Zinc Great Lakes CCC 60 nolL Great Lakes Initiative Rules

Benzoldeflphenanthrene 24-hr LC50 2,000 uolL Eisler 1987

Bis(2-ethvlhexvl)phthalate Tier II SCV 3 uolL Suter & Tsao 1996

Di-n-butvlphthalate Tier II SCV 32,7 u.n. Suter & Mabrev 1994

2-Methvlnaphthalene Tier II SCV (] -methvlnaphthalene 2,1 u.n. Suter & Tsao 1996

Dibenzofuran Tier II SCV 3,7 u.n, Suter & Tsao 1996

alpha-CWordane Tier II SCV 1.6 nolL Suter & Tsao 1996

ganuna-Chlordane Tier II SCV 1.6 nolL Suter & Tsao 1996

PCB 1260 Tier II SCV 94 nolL Suter & Tsao 1996

4,4'-DDD Tier II SCV 0,011 nolL Suter & Tsao 1996

4,4'.DDE Tier II SCV for DDT 0,013 u.n.4,4'-DDT Tier II SCV 0,013 u.n, Suter & Tsao 1996

1,I-DicWoroethvlene Tier II SCV 25 u.n, Suter & Tsao 1996

1,1,1-TricWoroethane Tierll SCV 11 u.n. Suter & Tsao 1996

Chloromethane Tier II SCV 2200 u.n. Suter & Tsao 1996

Carbon disulfide Tierll SCV 0.92 u.n. Suter & Tsao 1996

Mercury was the only biomagnifying COEC found in darter tissue above the MOL. Weiner and Spry (1996)

summarize the toxicological significance ofmercury in freshwater fish. They cite numerous studies showing

mercury in piscivorous fish (whole body) tissue (walleye, northern pike, largemouth bass) from unpolluted

waters to range from the levels found in Brush Creek darters to an order ofmagnitude higher. Neurotoxicity

Iowa Army Ammunition PlantEcological Risk Assessment Addendum fDraft Fina/J

March 20, 1998Page 4-25

is considered here to be the most probable chronic response of wild adult fish exposed to mercury. Symptoms

include uncoordination, inability to feed, and diminished responsiveness. Weiner and Spry cite studies of one

year old walleye (taxonomically related to darters) in which no adverse effects were observed in fish having

tissue levels of 2.5 mg/kg wet weight. That level is ten times the highest level found in Brush Creek darters.

In another cited study of brook trout, Weiner and Spry described mercury muscle tissue residues for a no

observed-effect level (NOEL) to be 5 mg/kg, twenty times greater than the highest level found in Brush Creek

darters. Hence, a conservative criterion for a no-observed-adverse-effect level (NOAEL) mercury residue on

darter reproduction is assumed to be 2.5 mg/kg wet weight.

4.3.1.4 Risk Estimates. Hazard quotients (HQs) were computed as the exposure point concentration

(95%UCL) in Brush Creek divided by the aquatic RTV and are presented in Table 4-24. An HQ of 1.0 or

greater suggests an ecological risk. Based upon available data and the above described approach, possible risks

would be expected for lead, silver, thallium, and barium. HQ values for explosives and other organic COECs

were all less than 1.0. Thus, these COECs do not pose a risk to the survival of the orangethroat darter.

Table 4-24. Aouatic BazardOuotients for Brush Creek Watershed

COEC Exno,ure Point Concentration, (uolLl RTV Hazard Ouotients1,3,5-Trinitrobenzeoe 6.0 120 0.05

2,4,6-Trinitrotolueoe 58.9 130 0.5

HMX 51.3 3300 0.02

RDX 248 4,900 0.05

Te'~l 1.8 3000 0.001

Aluminum 50 3288 0.02

Chromium 14.9 68 0.2

Iron 700 1300 0.5

Lead 21.6 18.9 1.1

Mercn~ 0.189 120 0.002Silver 5 0.36 14Thallium 20.5 12 1.7Barium 76 4 19Bervllium 3.1 57 0.05

Selenium 1.9 88.3 0.02

Zinc 5 60 0.08

Cobalt 5 23 0.2Manaanese 30 120 0.2

Vanadium 5 20 0.3

Benz;;rd~heoanthrene 2.1 2000 0.001

Chloromethane 1.9 2200 0.0009


March 20, 1998Page 4-26

Background concentrations of metals were not part of the data screening algorithm shown in Exhibit 3-2.

Based upon eight samples, JAYCOR (1996) defined background concentrations for total concentrations of

these four metals. Table 4-25 compares these background levels to 95% UCL concentrations of total

(particulate plus dissolved) metals.

Table 4-25. Comparison of Background and 95%UCL Concentrations

(/lg/L) of Metals in Brush Creek

Metal Background 95%UCL

Lead lto5 22

Silver 5 10.4

Thallium 7 20.5

Barium 111 to 227 132

Of these four metals, the 95%UCL concentrations of total barium are within the expected range for

background. Hence, while the dissolved EPC for Ba may exceed the RTV by a factor of 19, the potential for

adverse effects is due to natural sources.

Mercury was the only biomagnifYing COEC found in darter tissue above the MDL. Using the criterion for a

NOAEL mercury residue on darter reproduction of 2.5 mglkg wet weight, and the mercury residues in darters

(Table 4-13), HQs for mercury biomagnification effects on the assessment endpoint range from 0.05 to 0.1.

4.3.1.5 Aquatic Macroinvertebrate Community Structure. The health of the aquatic benthic

community was measured using the Rapid Bioassessment Protocol III, as discussed in Section 3.8. The

Protocol results for Brush Creek are presented in Table 4-26.

Table 4-26. Rapid Bioassessment Protocol ill for Brosh Creek

Station Number BC9 BCIO BCI BC2 BC3 BC4 BC5 BC6 BC7 BC8MI • Species Richness 13 12 8 11 12 8 12 13 10 17

Biological Condition Score 6 6 4 6 6 4 6 6 4 6M2 - HEI (modified) 6.3 7.2 6.2 5.4 4.8 5.6 4.9 4.6 4.7 4.7

Biological Condition Score 6 6 6 6 6 6 6 6 6 6M3 . ScraperslFilterers 3% 68% 0% 1% 0% 0% 13% 16% 0% 26%

Biological Condition Score 6 6 0 4 0 0 6 6 0 6M4 - EPTIChironomidae 150% 117% 3833% 820% 275% 74% 143% 258% 993% 298%

Biolol!ical Condition Score 6 6 6 6 6 2 6 6 6 6


March 20, 1998Page 4~27

I U-ununpaIred, S-shght Irnpamnent, Ref=reference

Table 4-26. Rapid Bioassessment Protocol ill for Brusb Creek

Station Number BC9 BClO BCl BC2 BC3 BC4 BCS BC6 BC7 BCSM5 • %Dominant Taxon 60% 61% 54% 55% 63% 37% 46% 54% 50% 55%

Biological Condition Score 0 0 0 0 0 0 0 0 a 0

M6 - EPT Index 3 2 I 4 3 3 4 7 4 8Biological Condition Score 6 0 0 6 6 6 6 6 6 6

M7 - Community Loss 0.00 0.50 0.88 0.55 0.50 1.00 0.50 0.69 0.80 0.35Biological Condition Score 6 4 4 4 4 4 4 4 4 6

M8 - Shreddersffotal 70% 45% 25% 23% 8% 10% 47% 45% 16% 4%

Biological Condition Score 6 6 4 2 a 0 6 6 2 0% Comoarison to Reference Score 100 82% 57% 81% 67% 52% 95% 95% 67% 85%

Biological Condition Category' Ref U S U S S U U S U

-

Sampling sites throughout the Brush Creek watershed were generally similar to the BC9 reference site.

Stations BCI, 3, 4 and 7 were rated as slightly impaired, differing from other stations largely on the basis of

the ratio of scrapers to filter feeders, low Ephemeroptera, Plecoptera, Tricoptera (EPT) indices, and low

proportions of shredders. These differences indicated communities that were based more on fine particulate

organic matter in the water column (a condition generally indicative of organic pollution) than on leaves and

other coarse particulate organic matter. However, most stations (including the stations that were rated as

slightly impaired) scored better than the reference station for several metrics. (Unfortunately, Biological

Condition Scores allow no credit for exceeding the metric scores for the reference station.) Because most of

the watershed is intensively cultivated, the reference station itself possibly represents a slightly impaired

condition. Nonetheless, the impairment exhibited at those stations having Biological Condition Scores

suggesting a slightly degraded condition is considered to be more the result of agricultural practices at the site

than caused by lAAAP operations.

4.3.1.6 Uncertainty. Significant uncertainty is attributed to the risk estimates for three metals (lead,

thallium, and silver). Principal uncertainties are described below.

• Uncertainty regarding the slight aquatic risk shown for lead is due to the use of regression equations

to predict the lowest chronic value for lead (18.9 IlgIL). The estimated risk quotient is 1.1, which is

well within the limits of uncertainty ofthe prediction ofthe chronic RTV.

• Tha1lium risks are likely overestimated, again due to the conservative nature ofthe Tier II procedures.

Chronic toxicity ofthallium to fathead minnow (Pimephales promelas) is 56.9 IlgIL, and, for Daphnia

magna 134.5 IlgIL (Suter and Tsao 1996).


March 20, 1998Page 4·28

• Silver risks are predicted from the SCV from Suter and Tsao (1996). These researchers recommended

the Tier IT SCV of 0.36 flgIL computed from Final Acute Values and acute-to-chronic ratios for three

species, even though the USEPA questioned two ofthese three ratios. Given this, and the generally

conservative approach in the Tier II SCV estimations, we judge the hazard quotient for silver to be

highly uncertain, and likely an overestimate.

• The uncertainty for the risks posed by the explosive and organic COECs is considered to be low to

moderate, largely because the RTVs for these compounds were based on species other than the

orangethroat darter and other resident fauna. Aquatic ecotoxicity tests are typically performed on to

fathead minnow, Daphnia magna, rainbow trout (Oncorhynchus mykiss) or other standard organisms.

• The uncertainty of the HQfor mercury biomagnification and adverse effects on darter reproduction

is considered to be moderate. Field measurements oftissues residues were measured, a more accurate

assessment of exposure than modeling. However, although young walleye, the test species for the

selected effect criterion, are in the same family as darters, there are physiological differences between

that species and orangethroat darter. Nonetheless, the similarity was believed to be sufficient that no

uncertainty factor was applied to the mercury RTV.

• By comparison, the uncertainty of the Rapid Bioassessment Protocol III is judged to be low. The

technique is widely used for evaluation of aquatic impacts and is considered a reliable tool by

regulatory agencies in nearly all states. Iowa DNR routinely includes stream bioassessments in new

NPDES permits as a monitoring requirement. The Protocol III includes eight metrics, and impacts not

assessed by one metric should be evaluated by another. Hence, the benthic community assessment

should provide the greatest level of accuracy with the least uncertainty.

4.3.1.7 Summary of Aquatic Risks. In summary, the aquatic ecosystem of Brush Creek does not

appear to be currently impacted by IAAAP operations. Evidence indicating aquatic risks from lAAAP

operations on the Brush Creek watershed are minimal. There is no evidence that explosive or other organic

COECs pose a risk to the aquatic ecosystem. The benthic community structure does not show degradation

downstream ofIAAAP operations. Because this is considered the most reliable measure of aquatic ecosystem

health in the aquatic risk assessment study with the least uncertainty, the conditions at IAAAP are considered

to pose little risk to the aquatic biological community in the Brush Creek watershed. Slight to moderate risk


March 20, 1998Page 4-29

of low-level adverse effects from the metals lead, silver and thallium is predicted, but these predictions are

judged to have moderate to high uncertainty.

4.3.2 Terrestrial Ecosystem

The assessment endpoints for the terrestrial ecosystem are the health ofthe vascular plant community and the

viability ofwildlife populations. Body burdens of COECs in small mammals collected in floodplain habitats

were measured and evaluated in the context of existing toxicity information. Because of federal listing as a

threatened species, the viability of the bald eagle (Haliaeetus leucocephalus) also was assessed. To assess

the health of the vascular plant communities potentially affected by chemical contamination, the site quality

indices of such communities (especially on the species richness metric) as determined by Horton et al. (1996),

was the measurement endpoint.

4.3.2.1 Chemicals of Ecological Concern. Table 4-27 lists the COECs identified from screening the

Brush Creek watershed soils database.

Table 4-27. Preliminary Terrestrial COECs for Brush Creek Watershed

Contaminant Maximum (mglkg) 95% VeL (mglkg)

1.3,5.trinitrobenzene 23,000 1.2

2,4,6.trinitrotoluene 100,000 27.1

HMX 6,700 11.2

RDX 7,200 7.04

Tetryl 8,300 0.47

Aluminum 21,800 10,556

Chromium 1,530 37.8

Iron 94,000 18,589

Lead 13,000 206

Mercury (biomagnifier) 2,000 0.446

Silver 260 0.57

Thallium 67.3 18.3

Benzo[def]phenanthrene 100 0.97

Bis(2-ethylhexyljphthlate 2.1 1.13

Di·n·butyl phthlate 6.2 0.55

Dibenzofuran 30 0.119


March 20, 1998Page 4·30

Table 4-27. Preliminary Terrestrial COECs for Brosh Creek Watershed

Contaminant Maximum (mg/kg) 95% UeL (mglkg)

4,4'-DDD (biomagnifier) 12,000 0.794

4,4'-DDE (biomagnifier) 21,000 2.007

4,4'-DDT (biomagnifier) 77 0.267

a-Chlordane (biomagnifier) 880 >880

y-Chlordane (biomagnifier) 640 >640

Arochlor 1260 (biomagnifier) 100 2.398

The values shown in Table 4-27 are for the entire watershed, and include "hot spots" such as spill areas or

waste pits. Therefore all potential ecological exposure pathways should be implicitly considered. Five

explosives, seven metals, four base neutral organics and six pesticideslPCBs are listed. All data used to

generate the table were taken from the JAYCOR database provided by IAAAP to Harza.

The assessment endpoint for terrestrial high trophic level consumers exposed via their diet is reduced

reproductive success. The measurement endpoint is body burdens of COECs in prey (small mammal and fish

tissue). Utilizing the body burdens of contaminants in shrews and darters, the likely body burdens of those

contaminants in a sensitive tertiary consumer, effects on the federally-listed threatened species, the bald eagle,

can be projected and evaluated using literature-based NOAEL benchmarks for effects.

The Final Water Quality Guidance for the Great Lakes System (USEPA 1995) identifies pollutants that are

bioaccumulative chemicals of concern. Bioaccumulating COECs tend to be lipophilic and slow to be

metabolized, and as a result build up in organisms and magnifY up the food chain. Therefore, even though

relatively low concentrations may be present within soils, sediments or water at a site, high levels can build up

in biological tissues and special attention should be paid by risk assessors. If the COEC does not

bioaccumulate in higher trophic levels, then protection of lower level prey species would also protect higher

order predators such as the bald eagle. In other words, hazard quotients for non-bioaccumulating COECs that

are acceptable for prey species (i.e. mice, shrew, vole) will also be acceptable for higher predators.

Within the Brush Creek watershed, terrestrial COECs passing the prescreening process include mercury, p,p'

DOD, DDT, DOE, dibenzofuran, PCB 1260, and chlordane. Aquatic COECs that tend to bioaccumulate were

limited to mercury; this is important to bald eagles because they tend to consume significant amounts of fish

(Table 4-28).


March 20, 1998Page 4-31

4.3.2.2 Exposure Estimation. Soil samples and mammal (white-footed mouse, meadow vole and short

tailed shrew) tissues were collected at specified locations in the Brush Creek watershed to assess the risk to

viability ofwildlife populations. The habits ofthe mammals analyzed for contaminant residues are summarized

below, as taken from Schwartz and Schwartz (1981).

White-footed mice live primarily in wooded areas, brushy borders or fence rows. Their nests may be in tree

cavities, old bird or squirrel nests, or underground beneath protective cover. The home range is generally

small, about 1/5 acre. White-footed mice nest in trees, shrubs, rocks crevices, under logs, and occasionally

in burrows that have been dug by other species. Notoriously omnivorous, preferred foods of white-footed mice

include insects, worms, seeds and fruit, with the relative amounts depending upon availability.

Meadow voles typically inhabit moist, low areas in thick grassy areas near streams or wetlands. They

construct runways in the cover and sometimes beneath the ground, where their nests are constructed of dried

grasses. Their preferred diet is the tender stems, leaves, roots, flowers and seeds ofgrasses, sedges and other

plants, but they are opportunistic and omnivorous feeders and will eat insects, snails, crayfish and other

rodents. Voles are known to consume their own weight each day. Jackson (1961) reported that meadows voles

may nest above ground or in burrows up to nine inches deep.

Short-tailed shrews live in dark, damp, or wet localities or fields with heavy weedy growth. Shrews run about

the surface ofthe ground or tunnel under mossy banks, old logs, or forest leaf litter in search of food. Runways

and tunnels of other mammals are commonly used, and on occasion, a shrew digs its own tunnels. Schwartz

and Schwartz (1981) indicate shrew tunnels are located just below the surface of the ground, but may be as

deep as 22 inches. Females build nests in the tunnel system. Shrews are extremely active, spend little time

resting, and do not hibernate in winter. Metabolic rates are quite high, more than 130 times that of man.

Home ranges are typically one-halfto one acre. Nearly the entire diet of shrews is comprised of animals, and

depend on availability. Insects, earthworms, snails, reptiles, birds, or mice are included, as short-tailed shrews

eat from half to more than their own weight each day.

Exposures were estimated using a combination of field measurements and predictive modeling. Exposure of

terrestrial animals to COECs was estimated as the sum of exposure from food, water and soil ingestion.

Dermal and inhalation exposures were assumed to be negligible. Bioconcentration factors (BCF) for

vegetation, aquatic animals and terrestrial animals were taken from the literature (Baes et al. 1984, Schneider


March 20. 1998Page 4·32

et aI. 1995, Garlen and Trabalka 1983, Veith et al. 1979). In some cases, BCF literature values were

unavailable, specifically for some organic COECs. In these cases, the BCF was estimated from the octanol

water partition coefficients (K"w). BCF for vegetation (BCF,) and for terrestrial herbivores (BCF.) were

estimated using the equations of Travis and Arms (1988). BCF for aquatic animals (BCFJ was estimated

using the equation provided by Mackay (1982):

10gBCFv=1.588 -O.578·logKow

logBCF,=l.033·logKow -7.735

logBCFo=logKow-1.32

Vegetation COEC residues were estimated as the product of BCF, and soil COEC exposure point

concentrations. Two sources of information on soil contamination were used. In most cases, the soil

contaminant database from JAYCOR was used to estimate exposure point concentrations (Appendix B), as

the lower of the maximum or the 95% VCL of the arithmetic mean oflog-transformed data. Where no data

were collected by JAYCOR, or the data were considered outdated, data from Tables 4-18 through 4-20 were

used. In instances where COEC soil concentration was less than the MDL, 50% of the MDL was used.

The daily COEC dose from vegetation ingestion was estimated as the product of the estimated residue

concentration, food intake by the consumer in an average day, and the proportion of vegetation in the

consumer's diet. Wildlife reference values (Table 4-28) for food and water ingestion, body weight and diet

composition were taken from VSEPA (1993). Seasonal variations in diet composition were ignored and annual

averages were used when seasonal data were available.

Table 4-28. Standard Animal Values

Parameter Mouse Bald Ea21e Mallard

Bodv weillht (kg) 0.022 4 1.1

Food intake (kt!lk2·d) 0.15 0.12 0.5133

Water intake (kgfkg-d) 0.04 0.036 0.057

Soil intake (portion of diet) 0.02 0.02 0.02

Exposure modification rate 1 0.05 0.4

Diet

Iowa Army Ammunition PlantEcological Risk Assessment Addendum {Draft Fina/}

March 20. 1998Page 4-33

Table 4-28. Standard Animal Values

Parameter Mouse Bald Ea21e MallardInvertebrates 0.214 NA 0.7Vegetation 0.786 NA 0.3

Fish NA 0.767 NA

Mammals NA 0.068 NA

Birds NA 0.165 NANA - Not apphcable.

COEC dose from water ingestion was estimated as the product of daily water requirement and surface water

COEC 95% UCL. Soil ingestion rates were taken directly from Beyer et al. (1994) or estimated where Beyer's

field measurements were not available. In the case of the bald eagle, soil ingestion was assumed to be two

percent of daily food intake.

The bald eagle is known to prefer fish as its principal food. USEPA (1993) provides data on the composition

ofeagle diets. Based upon those data, the daily dose estimates used the following dietary composition: 77%

fish, 7% small mammals, and 16% birds. Darter COEC residues were measured, while COEC residues in a

preferred waterfowl (mallard) were estimated (Appendix C). COEC concentrations measured in eagle prey

(Tables 4-11 through 4-13 and 4-15 through 4-17) showed low levels ofmercury in darter residues at all three

stations sampled (BC3, BC6 and BC8) and very low concentrations of dieldrin, a cyclodiene insecticide, in

darter tissue at BC8. BC8 is an offsite sampling station downstream of lAAAP. Dieldrin is not a COEC for

this study and is likely due to agricultural activities offsite. No biomagnifYing COECs were detected in small

mammal tissue from this watershed.

To confirm that bio-magnification of COECs in the Brush Creek watershed is not posing significant risk to

special resources, potential doses ofthose COECs to bald eagles were estimated. Dose estimates to eagles were

limited to bio-magnifying COECs, under the assumption that if risks were acceptable at lower trophic levels

for non-biomagnifYing COECS, then risks would be acceptable at higher trophic levels. Eagle standard

reference values are tabulated in Table 4-28, taken from USEPA (1993). COEC residues in eagle prey were

either measured (fish or manunal tissue residues), or estimated (mallard) assuming steady state conditions, and

available bioconcentration factors, diet composition and !<ow values. Food chain effects were accounted for

in the dose estimated for terrestrial animals taken from Baes et al. (1984) and Garlen and Trabalka (1983).

Exposure modification rates (EMR) were assumed to account for migration and feeding in off-site areas; bald

eagle EMR was assumed to be 5%, a conservative estimate. Bald eagles tend to feed in expansive areas of


March 20, 1998Page 4-34

open water. Very little open water exists in the Brush Creek watershed, and eagles would not tend to feed

there, rather preferring the opportunities along the Mississippi River, Skunk River and, perhaps, Mathes Lake.

Appendix C provides a complete record of dose estimates to white-footed mice and to the threatened species

bald eagle. Table 4-29 below provides daily intake estimates for white-footed mice at the 95% VCL

contamination at three stations in Brush Creek.

Table 4-29. Estimated Mouse Doses (mg/kgld)

COEC BC9 BClO BC3

1,3,5-Trinitrobenzene 2.4E-OI 4.6E+OO 2.4E-OI

2,4,6-Trinitrotoluene 3.2E-03 1.4E-Ol 3.2E-Q3

HMX 5.1E-02 2.IE-QI 7.9E-Ql

RDX 1. 9E-0 I 1.2E+00 6.3E+00

Tetrvl 5.4E-02 5.4E-02 5.4E-02

Aluminum 5.2E+OI 3.9E+OI 9.0E+00

Chromium 8.8E·02 SSE-OI 3.6E-OI

Iron 6.5E+OI I.3E+02 2.5E+OI

Lead 2.5E-OI 2.3E-OI 1.8E-OI

Mercurv 3.0E-03 1.7E-02 5.9E-02

Silver 4.IE-02 6.3E-02 1.5E-Ol

Thallium 7.5E-03 7.1E-03 7.3E-03

Benzordeflohenanthrene 2.6E-04 91E-05 2.6E-04

Bis(2-ethvlhexvl) ohthalate 8.3E-Q3 O.OE+OO 2.6E-03

Di-n-butvl ohthalate 4.5E-04 O.OE+OO 4.5E-04

Dibenzofuran 4.0E-04 O.OE+OO 4.0E-04

4,4'-DDD 7.2E-05 5.9E-06 6.0E-06

4,4'-DDE 5.0E-05 4. IE-06 42E-06

4,4'·DDT HE-05 2.1E-06 2.2E-06

alpha-Chlordane 3.4E-06 31E-06 3.IE-06

Iganuna-Chlordane 3.4E-06 3.1E-06 3.1E-06

PCB 1260 1.4E·04 12E-05 1.2E-05

BC9 is the reference station for this watershed, located upstream. Station BC lOis at the southern end of Line

I, adjaceot to an area currently under remedial action. Station BC3 is just west of the wastewater treatment

plant (WWTP). White-footed mouse dose estimates were not prepared for BC6, near the southern boundary

of lAAAP, because the JAYCOR soils database did not have samples collected near this site, and soils

cootaminant data collected in this study (Tables 4-18 through 4-20) indicated the BC6 site to be one ofthe least

Iowa Army Ammunition PlantEcological Risk Assessment Addendum fDraft Final}

March 20, 1998Page 4-35

contaminated areas studied. If significant risks were not present at more contaminated sites, then BC6 would

not present significant risk to white-footed mice.

Table 4-30 below provides daily intake estimates for biomagnifying COECs at four stations in the Brush Creek

watershed. In general the estimated doses are similar from one site to the next, including the reference station.

This is due to the lack of detectable COECs in eagle prey resulting in use of 50% of the MOL for COEC

concentrations in eagle food.

Table 4-30. Estimated Doses to Bald Eagle of Biomaf!llifying COECs (mg/kg-d)

COEC BC9 BCIO BC3 BC6

Mercury 0.00017 0.00024 0.00050 0.00221

4,4'-000 0.00001 0.0000012 0.00001 0.00001

4,4'-00E 0.00001 0.000001 0.00001 0.00001

4,4'-00T 0.000005 0.0000009 0.000005 0.00001

alpha-Chlordane 0.00001 0.0000016 0.00001 0.00001

gamma-Chlordane 0.00001 0.0000016 0.00001 0.00001

PCB 1260 0.00005 0.000008 0.00005 0.00005

4.3.2.3 Effects. NOAEL values for white-footed mouse and bald eagle for all chemicals of concern at

IAAAP are provided in Table 4-31. Because the exposure pathway of COECs was limited to uptake via the

food chain, only COECs that biomagnify were evaluated for bald eagle. Values were taken from the literature,

and if necessary, scaled to white-footed mouse or eagle using the body weight ratio method of Sample et al.

(1996).

Table 4-31. COEC RTV for White-footed Mouse and RTV of Biomaf!llifviRl! COECs for Bald Eal!leCOEC Criterion I Dose I Units Reference

White-footed Mouse

1 3 5-Trinitrobenzene iNOAEL - P. leuconus 57.4 molko/d Redd et al 1995 cited in IRISI 3-Dinitrobenzene lNoAEL - rat 0.23 molko/d Talmaoe and Onresko 19962 6~Dinitrotoluene taken as 2 4 isomer 13.5 m!!lkl!!d2 4-Dinitrotoluene INOEL - mouse 13.5 m!!lkl!!d USACE 199612.4 6-Trinitrotoluene iNOAEL· P. leucoous 3 I m!!Ik./d Talma.e and Ooresko 1996Tet"'l !NOAEL - P. leuconus 2.4 molko/d Talmaoe et al 1996HMX !NOEL. rat 115 molko/d USACE 1996RDX lNoAEL - mouse 7.9 m!!lkl!!d Talma.. et al 1996l-\Iuminum NOAEL - P. leucoous 2.086 m!!lkl!!d Samole et al 1996Barium NOAEL - P. leucoous 10.80 m!!lkl!!d Samole et al 1996

Iowa Army Ammunition PlantEcological Risk Assessment Addendum fDraft Final}

March 20. 1998Page 4-36

Table 4-31. COEC RTV for White-footed Mouse and RTV of Biomagnifyinl1; COECs for Bald Eal1;le

COEC Criterion Dose Units ReferenceBervllium NOAEL - P. leucoous 1.32 molk./d Samnle et al 1996

Chromium NOAEL ICr+61- P. leuconus 6.55 m.Ik./d Samnle et al 1996

Cooner NOAEL - P. leucoous 30.4 m.Ik./d Samnle et ai 1996!Iron Standard lab animal diet concentration 147 molko/d Dierenfeld et al. 1996

ead NOAEL - P. leucoous 15.98 molk!!ld Samole et al 1996

ManlZanese NOAEL - P. leucoous 176 molk!!ld Samole et al 1996

Mercurv NOAEL - P.leucoous las Me-H.) 0.064 m.Ik./d Samnle et al 1996

Selenium NOAEL - P. leuconus 0.399 molko/d Samnle et al 1996

Silver OAEL - P. leuconus 0.105 molko/d IRIS

Thallium NOAEL - P. leucoous 0.0l5 molk!!ld Samole et al 1996

Vanadium h\JOAEL. P. leucoous 0.389 molk!!ld Samole et al 199617inc NOAEL - P. leucoous 319.5 molk!!ld Samole et al 1996

Benzofdel10henanthrene NOAEL • lab mouse 75 m.Ik./d IRIS

Bisl2-ethvlhexvD ohthalate NOAEL - P. leucoous 19.8 molk./d Samole et al 1996

Di-n-butvl nhthalate NOAEL - P. leuconus 594 m.Ik./d Samnle et ai 1996

2·Methvlnanhthalene 10% of anthracene NOAEL - lab mouse 100 molko/d IRIS

Dibenzofuran NOAEL • P. leucoous 0.00032 molk!!ld Samole et al 1996

aloha-Chlordane NOAEL - P. leucoous 5.0 molk!!ld Samole et al 1996

'lZamma-Chlordane NOAEL - P. leucoous 5.0 molk!!ld Samole et al I 996

PCB 1260 NOAEL (1254)- P. leucoous 0.061 molk!!ld Samole et al 1996

44'-DDD NOAEL - P. leucoous 1.6 m.Ik./d Samole et al 1996

4'-DDE NOAEL - P. Ieuconus 1.6 m.Ik./d Samnle et al 1996

4'·DDT NOAEL - P. Ieuconus 1.6 m.Ik./d Samnle et al 1996

I l-Dichloroethvlene INOAEL - P. leuconus 59.9 molko/d Samnle et ai 1996

I I I-Trichloroethane NOAEL - P. leucoous 1123 mglk!!ld Samnle et al 1996

Chloromethane NOAEL - P. leucoous 117 molk!!ld Samole et ai 1996

Carbon disulfide NOAEL. lab rats & rabbits 11 m.Ik!!ld IRIS

Bald Eav/e

Mercurv iNOAEL - bald eaole 0.0046 m.Ik./d derived from Samnle et al 1996

Dibenzofuran 10% of rat NOAEL • bald eaole 0.000009 molko/d derived from Samnle et al 1996

aloha-Chlordane NOAEL - bald eagie 0.4145 molko/d derived from Wiemaver cited in Bever et ai 1996

I.amma-Chiordane NOAEL - baid eagle 0.4145 molk!!ld derived from Wiemaver cited in Bever et al 1996

PCB 1260 NOAEL - bald ea.le 0.1266 molk!!ld derived from Samole et al 1996

L1.4'-DDD 10% of LOAEL for DDE - bald ea.ie 0.0458 m.Ik!!ld Lincer 1975 as cited on A-13 ofUSEPA 1996

44'·DDE 10% of LOAEL for DDE· baid ea.ie 0.0458 m.Ik./d Lincer 1975 as cited on A-13 ofUSEPA 1996

~.4'-DDT 10% of LOAEL forDDE· bald ea.ie 0.0458 m.Ik./d Lincer 1975 as cited on A-13 ofUSEPA 1996

Sample et al. (J 996) provides discussion about the toxic mechanism of many of these, and the others are

discussed in the cited studies. Little infonnation is available on the toxicity of metals that are naturally

abundant in soil, specifically aluminum and iron. The mouse RTV criterion cited above for iron was derived

from a study ofmineral nutrition in rodents. Shah and Belonje (J 991) studied the cbronic effects of dietary

iron and tissue residues in laboratory rats. We estimated the NOAEL dose from their study to be 147 mg/kg-d.

In another study, Dierenfeld et al. (J 996) analyzed iron in dry chow fed to mice (Mus musculus domesticus)


March 20, 1998Page 4-37

and rats (Rattus norvegicus), as well as iron in different life stages of the whole rodents. We estimated the

daily iron dose in the diets ofthe mice in Dierenfeld's stndy to be 46 mglkg/d. A LOAEL dose is likely quite

higher than the 147 mg/kg/d cited in Table 4-31. Researchers have generally agreed that mammals, including

rodents, can regulate the amount of iron retained in their body by eliminating excess iron. For example,

Sawicka-Kapusta ei al. (1987) found no siguificant differences in iron tissue residues in two species of small

mammals (yellow-necked mice or bank voles) from polluted versus unpolluted forests in southern Poland.

Studies of silver in mammalian systems have been conducted primarily with humans and rats as subjects.

Furchner et al. (1968) studied the absorption and retention of ingested silver in mice, rats, monkeys and dogs.

In all four species, very little silver was absorbed from the gastro-intestinal tract. Toxic effects of silver have

been reported primarily for the cardiovascular and hepatic systems. Olcott (1950) administered 0.1 % silver

nitrate in drinking water to rats for 218 days. This exposure (about 89 mg/kg/day) resulted in a statistically

significant increase in the incidence ofventricular hypertrophy. Upon autopsy, advanced pigmentation was

observed in body organs, but the ventricular hypertrophy was not attributed to silver deposition. Hepatic

necrosis and ultrastructural changes ofthe liver have been induced by silver administration to vitamin E and/or

selenium deficient rats (Waguer et al., 1975; Diplock et al., 1967; Bunyan et aI., 1968). Investigators have

hypothesized that this toxicity is related to a silver-induced selenium deficiency that inhibits the synthesis of

the seleno-enzyme glutathione peroxidase. In animals supplemented with selenium and/or vitamin E, exposures

ofsilver as high as 140 mg/kg/day (100 mg Ag/L drinking water) were well-tolerated (Bunyan ef al., 1968).

While the effects ofcWorinated pesticides, particularly DDT and metabolites, on raptor reproduction are fairly

well documented, the effects ofmercury are somewhat ambiguous. Literature on the subject generally indicates

no relationship between egg hatching success and dietary mercury concentrations up to 3 mg/kg (Thompson

1996, Wren ef al. 1995). The mercury NOAEL value, derived from Sample ef al. (1996) was obtained from

scaling up a NOAEL dose of O. 0064 mg/kg-d for mallard (Anas platyrhynchos) to the bald eagle. This method

provides a NOAEL dose of 0.0046 mg/kg-d, which we used in the HQ computation.

4.3.2.4 Risk Estimates. The risk estimates for the white-footed mouse and the bald eagle are presented

below.

White-footed Mouse. Table 4-32 provides NOAEL values and hazard quotients for risk to the white-footed

mouse. As many ofthese chemicals have different mechanisms of toxicity, summing them for estimation of

a hazard index is not appropriate.


March 20, 1998Page 4-38

Table 4-32. NOAEL Values aud Hazard Quotieuts for Wbite-Footed Mouse

Hazard Quotients

COEC NOAEL (mglkgld) BC9 BCIO BC3

1,3,5-Trinitrobenzene 57.40 0.004 0.08 0.004

2,4,6-Trinitrotoluene 3.00 0.001 0.05 0.001

HMX 115 0.0004 0.002 0.007

RDX 7.9 0.02 0.16 0.8

Tetryl 2.40 0.02 0.02 0.02

Aluminum 2.09 25 18 4.3

Chromium 6.55 001 0.09 0.06

Iron 147 0.4 0.9 0.2

Lead 16.0 002 0.01 0.01

Mercury 0.06 0.05 0.3 0.9

Silver 0.11 0.4 0.6 1.4

Thallium 002 0.5 0.5 0.5

Benzo[defJphenanthrene 75 0.000003 0.000001 0.000003

Bis(2-ethylhexyl) phthalate 20 0.0004 0.0001

Di-n-butyl phthalate 594 0.0000008 0.000001

Dibenzofuran 0.0003 1.2 1.2

4,4'-DDD 1.60 0.00005 0.000004 0.000004

4,4'-DDE 1.6 0.00003 0.000003 0.000003

4,4'-DDT 1.6 0.00002 0.000001 0.000001

alpha-CWordane 5.0 0.000001 0.000001 0.000001

ganuna-Chlordane 5.0 0.000001 0.000001 0.0000006

PCB 1260 0.1 0.002 0.0002 0.0002

Explosive chemicals do not appear to present any significant risk to small mammals in the Brush Creek

watershed. The HQ for RDX at BC3,just west ofthe WWTP, is 0.8, approaching the point where additional

contamination at the site could begin to be manifested in adverse effects there. Organic pesticides (with the

possible exception of dibenzofuran) and PCB 1260 also do not present significant risk to the white-footed

mouse.

Aluminum and silver may present some level of risk to white-footed mice at some ofthe sites. Aluminum has

the highest HQs at the reference site, BC9. Aluminum risk at "impacted" sites is less than risk at the reference

site. JAYCOR (1996) defined background AI concentrations at the IAAAP to range from 3,990 to 22,100

mglkg. Soil concentrations of Al at all three sites in this watershed were within this range. Risk to smaIl

mammals from aluminum in soils in the Brush Creek watershed are due to natural sources.


March 20, 1998Pag.4-39

The HQ for silver at BC3 is 1.4. The white-footed mouse RTV is a LOAEL dose, and it would therefore

appear that silver contamination at site BC3 presents a risk to small mammal populations. The effects should

be limited to the benign discoloration of skin tissue. Background concentrations of Ag in IAAAP soil were

defined by JAYCOR as 0.6 mg/kg, well below the 95%UCL concentration of 88 mg/kg for this site. Further,

in soils we sampled at small mammal traps set at BC3, silver was quantified to be 2.8 mg/kg.

Bald Ea&!e. Dose estimates, NOAEL values, and hazard quotients (HQ) computed for biomagnifYing COECs

consumed by bald eagle in the Brush Creek watershed are presented in Table 4-33.

Table 4-33. NOAELs and HQs for Bald Eagle

COEC NOAEL (mg/kgld) BC9 BCIO BC3 BC6

Mercury 0.1980 0.004 0.001 0.003 0.01

4,4'-000 0.0030 0.002 0.0004 0.002 0.002

4,4'-00E 0.0030 0.002 0.0003 0.002 0.002

4,4'-00T 0.0030 0.002 0.0003 0.002 0.002

alpha-Chlordane 0.4145 0.00002 0.000004 0.00002 0.00002

gamma-Chlordane 0.4145 0.00002 0.000004 0.00002 0.00002

PCB 1260 0.1266 0.0004 0.00006 0.0004 0.0004

Full tabulation of the computations are reprinted in Appendix C. NOAEL values in Table 4-33 are derived

from Sample et at. (1996). For example, Sample et ai. (1996) reference a NOAEL dose for mercury of 0.0064

mgikg-d for mallard (Anas piatyrhynchos), which when scaled up to bald eagle, provides a NOAEL dose of

0.0046 mg/kg-d.

DDT and its metabolites manifest their effects on raptor reproduction through egg-shell thimring. Because

ofthis, the sum ofthe HQs, or hazard indices (HI), was calculated. The IDs are extremely low, and range from

a low of0.00007 at BC I0 to 0.0003 for the reference site (BC9), and 0.0003 for BC3 and BC6. Chlordane,

or 1,2,4,5,6,7,8,8-octachloro-2,3,3a,4,7,7a-hexabydro-4,7-methano-IH-indene, is a cyclodiene insecticide.

Cyclodienes are a direct toxicity concern (rather than for reproductive failure), so summing the HQs would not

be appropriate.

These estimates indicate that none of the COECs represent significant risk to bald eagle reproduction in the

Brush Creek watershed. The maximum mercury concentration measured in eagle dietary items was 0.25 mg/kg


March 20, 1998Page 4-40

(for whole darter taken from BC6). Upstream and downstream concentrations ofmercury in fish are lower and

BC6 represents the worst case scenario for the watershed. We consider these estimates to be conservative.

4.3.2.5 Forest Quality Assessment. Horton et al. (1996) prepared a forest community quality

assessment for IAAAP, summarized in this section and interpreted as part of the ERAA. Horton's forest

community quality index was based on vascular plants and bryophytes, and was composed of six metrics:

1. Err vase =number of species of federal and state endangered or threatened vascular plants,

or species previously undocumented or recorded from fewer than six Iowa counties

2. Err bryo =number ofbryophyte species previously undocumented or recorded from fewer

than six Iowa counties

3. Rare vase = number of species of vascular plants new to, and/or considered rare in Des

Moines County and/or SE Iowa

4. Rare bryo =number of species ofbryophytes new to Des Moines County

5. Spp Rich vase = species richness of indigenous vascular plants

6. % indig = percentage of flora comprised of indigenous vascular plant species

Horton et al. inventoried 30 forest community sites in, or near, the IAAAP and scored them according to the

above six metrics. The numerical results ofthe surveys for each ofthe six metrics for all 30 sites were divided

into five equal classes, each class representing 20% ofthe sampled population. Each class (and the numerical

values in that class) assigned a class score between 0 and 5 representing the twentieth percentile that the forest

tract ranked. For example, the 20% offorest tracts with the highest number ofvascular species were assigned

a score of 5. A site quality index for each locality was then the sum of the class scores across all six metrics.

The numerical values ofeach metric and its class score (in parentheses), and site quality indices for these sites

are given in Table 4-34. Sites where data were insufficient to calculate a metric are denoted (ID) for that

metric.

Table 4-34. Relative Quality of Forest Communities, Brush Creek Watershed, IAAAP

Locale Site EfT vase EIT bryo Rare vase Rare bryo Spp Rich vase % indig Index

N of Mid Augusta Rd 0 1 (I) 4 (I) 2 (I) 83 (2) 87 (2) 7

NofRoadK BC6 a 2 (3) 7 (2) 8 (4) 112 (3) 84 (I) 13

Tributary S ofRoad K 0 a a a 34 (I) 87 (2) 3

Iowa Army Ammunition PlantECDlogical Risk Assessment Addendum (Draft Final)

March 20, 1998Page 4-41

Table 4-34. Relative Quality of Forest Communities, Brush Creek Watershed, IAAAP

Locale Site EfT vase EIT bryo Rare vase Rare bryo Spp Rich vase % indig Index

S ofRoadK 0 0 2 (I) 1 (I) 81 (2) 93 (4) 8

The class scores for each metric value and their resulting sum (the site quality index) reflect the ecological

condition ofa site in comparison with other sites within and beyond the Brush Creek watershed. Horton et of.

classified sites having a site quality index (SQI) greater than or equal to 20 as "exceptional," and sites within

an SQI of 10-19 as "significant." Sites with SQI scores ofless than IO were "considered ofmarginal value

as natural areas." Although the site quality index was developed and used by Horton et 01. to define the value

of a site as a natural area, it is assumed for the risk assessment that sites having current "exceptional" or

"significant" site quality characteristics are not degraded by chemical contamination. However, it is also

recognized that sites identified as "marginal natural areas" may have been altered from a higher index "natural

state" by factors other than chemical contamination. Foremost among such factors would be land clearing and

agricultoral activities on the IAAAP property.

As seen in Table 4-34, the site north of Plant Road K represents the highest quality forest in the Brush Creek

watershed, likely related to its relatively large size (Horton et 01. 1996). Contamination in the drainage is

heaviest in the northern, upland areas ofthe drainage and affects the site north of Plant Road K more than sites

south ofthat road. Therefore, it appears that 1AAAP fucility development, through restriction of forest lot size,

may be limiting forest quality to the same or more degree as contamination.

4.3.2.6 Uncertainty. We consider the uncertainty associated with the estimate of risk from COECs to

wildlife populations to be moderate to high, erring on the side of conservatism.

• Most RTVs used in the terrestrial study are NOAEL estimates, more conservative than LOAEL doses

for estimating risk. Even HQs exceeding unity may not result in toxic symptoms in an individual

associated with the LOAEL dose. LOAEL dose may be as much as ten times greater than estimates

for NOAEL doses.

• Research on the toxic effects of silver are ambiguous, and we have used a LOAEL dose based on

human subchronic stodies, extrapolated to mouse based upon body weight ratios. The endpoint in

those stodies was argyria, a medically benign condition involving the discoloration of skin.

Application ofthis endpoint to mouse populations is an overestimation of risk.


March 20, 1998Page 4-42

• The only other metal indicatedd to possibly present risk is aluminum, which is found naturally in

relatively high concentrations in soil. Aluminum in background sites at IAAAP is up to 22,100 mg/kg

(JAYCOR 1996) so the levels in the Brush Creek ERAA sites are not elevated above background. The

BCF, for aluminum is likely over estimated by Baes et 01. and results in high uncertainty in the

aluminum dose estimate. Weight of evidence indicates that mammals can eliminate excessive levels

of aluminum from their systems.

• The exposure modification rate used in the bald eagle dose estimates was 0.05. This implies that bald

eagle would be obtaining 5% offood from the Brush Creek watershed. This is extremely unlikely,

given the lack of preferred foraging habitat in that basin, and the estimate must be considered

conservative. Further, the RTV for mercury is quite conservative, but perhaps warranted as the effects

of mercury on raptor reproductivity are somewhat ambiguous and poorly defined.

4.3.2.7 Summary of Terrestrial Risks. As the white-footed mouse is a valid surrogate for other flood

plain-<iwelling rodents with similar feeding habits (i.e. shrews, voles, other mice, moles), explosives, pesticides,

and PCBs do not appear to present any significant risk to small mammals in the Brush Creek watershed, with

the possible exception ofdibenzofuran. Silver may present some level of risk to small mammals at BC3, near

the WWTP. Bald eagles do not appear to be at significant risk. Terrestrial community analysis does not

provide any evidence supporting adverse impacts from IAAAP operations.


March 20, 1998Page 4-43

_ •• _ •• - PLANT PROPERTY BOUNDARY

,_,V,l'e ,

, {:~I. '

L L E

,-'

, "~,

----

ROAD NAME

DRAINAGE BASIN BOUNDARY

EXHIBIT 4-1

SURFACE WATER DRAINAGESIOWA ECOLOGICAL RISK ASSESSMNET ADDENDUM


Scale O""'''''''',,;2;oOOO''''"=;;;i4..000;;;,,''''''',;;6;;;OOO~="''''8000Feet

J--IAR..ZA. Consulting Engineers and Scientists

~11.'~~

i""--------------------------------------------_.......

.,;,-'

SOURCE: Taken from Harza 1997a

EXHIBIT 4-2

LEGEND:

TASK 7: SEDIMENT/SURFACE WATERSAMPLE LOCATION

FLOW METER LOCATION

ROAD NAME

_ •• _ •• - PLANT PROPERTY BOUNDARY

SEDIMENT SITESIOWA ECOLOGICAL RISK ASSESSMENT ADDENDUM


scale 0"",,,,,,,,,;2:;:;00,,,0:::-,...;4,,,0.,00;:,,,,,,,,,;6;,:;00,,,0,=...:;8,,000 Feet

I---IAR.ZA. Consulting Engineers and Scientistsi'IL- _

5.0 LONG CREEK WATERSHED



Long Creek originates about two miles north of the site's northwest corner and drains most of the western

portion ofthe IAAAP. The stream exits the plant at the southwestern boundary, after draining approximately

7,700 acres ofthe IAAAP property. Long Creek joins the Skunk River just south of the site, and the latter

flows into the Mississippi River about 9 miles east.

Long Creek has been dammed near the center of the installation to create George H. Mathes Lake, with a

surface area of approximately 83 acres. Originally for water supply, use of the lake for this purpose was

discontinued in January, 1977. There is also a smaller lake, Stump Lake, located north of Mathes Lake that

is about seven acres in area. Stump Lake is a human-made sediment control structure that is presently being

cleaned out, expanded, and restructured for safety. Sediment cleaned out of Stump Lake was used for topsoil

and as a seed bank for phytoremediation wetlands at Lines I and 800. Stump Lake is fed by intermittent

streams and drains via intermittent streams into Long Creek. The stream valley and floodplain are deepest

(120 feet) and widest (500 feet) at the southern plant boundary.


Exhibit 3-1 is a map of land use at the IAAAP, and tabulated areas of each classification for this basin are

presented in Table 5-1. The predominant land use/land cover of the Long Creek basin is upland forest,

followed closely by agriculture.

Table 5-1. Lonp Creek Watershed Land UsefLand Cover

Land UselLand Cover Acres Percent

Unland Forest 2,693 35%

FJoodnlain Forest 483 6%

OldField 1,073 14%

Other Wetlands 2 0%

Auriculture 2,487 32%



Table 5-1. Lone Creek Watershed Land VselLand Cover

Land UselLand Cover Acres Percent


Open Water, PondiLake 128 2%

Residential 69 1%



Total 7,669 100%

In 1996, an inventory and assessment of habitats and biota of the IAAAP was published (Horton et al.).

While their objective was to assess the entire facility, they focused on natural areas along creeks and

drainageways, where temperate deciduous forest predominates. At IAAAP, the current flood plain forest

is characterized by the cominance ofcottonwood (Populus deltoides), black willow (Salix nigra), sycamore

(Platanus occidentalis), honey locust (Gleditsia triacanthos), green ash (Fraxinus pennsylvanica), northern

hackberry (Celtis occidentalis), elm (Ulmus spp.), poison ivy (Rhus radicans), grape (Vitus spp.), multiflora

rose (Rosa multiflora), brambles (Rubus spp.), and numerous species of forbs, grasses and sedges (Horton

et al. 1996).


Although the bald eagle (Haliaeetus leucocephalus), listed as threatened in federal regulations, has been

observed to consume fish from Mathes Lake (JAYCOR 1996), Horton et al. (1996) reported that their

surveys found no federally listed endangered species on the IAAAP property. Five species of state

threatened plants were reported in the Long Creek watershed. Horton et al. (1996) reported sightings of river

otter (Lutra canadensis), but questioned the validity of that record and opined that river otter is not on the

property. Orangethroat darter (Etheostoma spectabile), present in other lAAAP drainages, were not reported

in Long Creek and their absence was confirmed by Harza ecologists during the field program. Biological

resources of special concern within the Long Creek watershed are listed in Table 5-2.



Table 5-2. Protected Species in the Long Creek Watershed

Locality Species

Peninsula in Mathes Lake. Eof Road C. Blephi/ia ciliataS V, ofSE 114, Sec. 12 & adjoining comers of Sec. 7,18,13, T69N, R4W false hellebore (Verarrum woodii)

SW shore of Mathes Lake Nof Plant Road I. blue ash (Fraxinus quadrangu/ata)NI12, Sec. 13 & SW 114 ofSE 114, Sec. 12, T69N, R4W

Wside & tributary to W, Nof Plant Road K. Blephilia ciliataN V, (mainly NW 114 & WV, ofE v,), Sec. 19, T69N, R3W

SofPlant Road K. Blephi/ia ciliataSE 114, Sec. 19, T69N, R3W blue ash

sharpwing monkey- flower (Mimulus a/atus)false hellebore

SE comer of Yard Kjust Sof Middle Augusta Road. slender lady tresses (Spiranthes [acera)NE 114 ofNE 114 ofNE 114, Sec. 24, T69N, R4W

Uplands along tributary WofLong Creek, Nof Road K& SE of Yard K. slender lady tressesNW 114 ofNW 114, Sec. 19, T69N, R3W

SE end of Stump Lake. river otter (Lutra canadensis)NW 114 ofSW 114, Sec. I, T69N, R4W


Long Creek drains the west-central parts ofIAAAP and is tributary to the Skunk River. Long Creek is deeply

incised in the glacial drift and bedrock throughout the southern part of the site and is impounded by Mathes

Dam in the central portions. In general, bedrock is shallow in these areas with limestone exposed

intermittently, but frequently, in the creek valley and around Mathes Dam and Reservoir. Shallow

groundwater flow is toward the creek, paralleling topography, and discharges to the creek from both bedrock

and drift. Although few wells are available around Mathes Reservoir, the lake is expected to exert significant

influence on local flow patterns. In the northern part of the drainage, the creek is less deeply incised and the

drift is thicker, exceeding 130 feet thick locally, reflecting the northwest part ofa buried bedrock valley.

The bedrock in the Long Creek watershed is overlain by a layer of sandy silty clay. The bedrock beneath

the downstream reaches ofLong Creek have a greater possibility of contamination than in the Brush Creek

watershed due to the shallowness of the bedrock and the sandy material existing above bedrock. A spring

on the north side of the mid-section ofLine 3A, that drains to Long Creek, influences shallow groundwater

Iowa Army Ammunition PlantEcological Risk Assessment Addendum roraft Final}

March 27, r998Page 5-3

on that half of the line. This half of Line 3A contains the majority of the buildings at the line.

5.1.5 Facilities

The facilities in the Long Creek Watershed include a portion of Line 3A, Line 4B, Line 5B, Line 8, small

portion of Line 800, Inert Disposal Area, Fly Ash Landfill, Construction Debris Landfill, Firing Site,

Building 600-86, and the Fly Ash Disposal Area. Descriptions of the facilities found in the watershed are

contained in Table 5-3.

Table 5-3. Facilities in Long Creek Watersbed

Facility Size! Period of Function WastewaterlW85te Contaminants ofBldg, Operation Concern

Une 3A 119 1943-1945, Explosives·related Wastewater is processed through a Explosivesacres! J7 1949-1989, processing, loading, carbon filter, discharged (NPDES #35) Metalsbldgs recently assembly, and packing. to intermittent creek that flows for one PCBs

reopened Presently, production mile and then joins Long Creek.of the Volcano anti-tank mine.

Line 4B 16 acres 1941-1945, Components, missile, Wastewater was stored in either in· Explosives1962-date, and fuse assembly. ground or above·ground tanks, removed Metalscurrently and treated elsewhere.inactive

Une 5B 41 acres! 1942-1945, Pelletizing and Explosives contaminated wastewater Explosives18 bldgs I949-date, assembly of adaptor processed through carbon filter columns Metals

currently boosting tetryl. and discharged to NPDES outfall (#052).inactive

Line 8 69 acres Constructed Amatol (ammonium Runoff from coal piles leached into Metalsand used nitrate) production, ravine to east. Dam constructed alongduring fertilizer production; tributary to Long Creek. ResultingWWII, fuse and rocket igniter sludge periodically excavated andclosed 1950 LAP operations. landfilled.

Line 800 See Brush Creek Watershed Small portion of Line 800 drains Explosivessouthwest in an intennittent stream to MetalsLong Creek.

Inert Closed in Sanitary landfill, Waste buried there including residential MetalsDisposal 1984. burning field, metal waste, plastic, metals, asbestos AsbestosArea Trench 6- salvage operation, insulation, ash from explosive waste SVOCs

RCRA unit. sludge drying bed, and incinerator. Surface run-off from area VOCsTrench 5- clay-lined holding area. reaches Long Creek only during heavycapped; rain or melting ice and snow.othertrenches tobe capped.



Table 5-3. Facilities in Long Creek Watershed

Facility Size! Period of Function WastewaterlW85te Contaminants ofBldgs Operation Concern

Fly Ash 9.5 acres 1985 to Accepts fly ash from Fly Ash. No hazardous waste disposed in MetalsLandfill present coal-fired heating plant. landfill. Sulfates

Construction 3 acres 1940s to Debris stored on Debris. ExplosivesDebris present surface soil. MetalsLandfill PesticidesIPCBs

Firing Site 459 1940s to Three areas with firing Radioactive material in soil was Radionuclidesacres present pads used for static removed.

testing of warheads;destructive testing of701 shot of 0-38 andhigh explosives.

Bldg 600-86 1941 to Central Chemical Lab RCRA waste. Metalspresent till 1953. Presently,

permined RCRAhazardous wastestorage facility.

Fly Ash 5 acres 1940s - Disposal of fly ash, Fly Ash. MetalsDisposal 1950s residual coal, and other SulfatesArea residue from coal-fired

plant.


5.1.6.1 Soils. Within the Long Creek Watershed, RDX and lead were reported at low levels in a drainage

way southwest ofLine 800 into Long Creek and elevated lead concentrations were found in two soil samples.

Radionuclides above detection limits were reported in surface soils at the North Test Site, the South Test

Site, and Pad FS-14. Table 5-4 summarizes soil contamination in soil samples by JAYCOR (1996).



Table 5-4. Soil Contamination in Long Creek Watershed

Facility Soil Sampling Results

Line 3A • 2.4,6-TNT and RDX were detected in soils near Line 3A at levels up to 19,000 and 11,000 ~g!g,

respectively. HMX was detected at levels up to 1700 ~glg. 1,3,5-TNB was detected as high as21 ~glg while 2,4-DNT was detected up to 13.2 ~glg. Minor contamination by 1,3-DNB, 2,6-DNT and nitrobenzene were also detected. The majority of explosives were detected aroundBuilding 3A-05-1 and its associated buildings (3A-140-3, 3A-140-7 and 3A-70-1). There was atrend for explosives concentrations to decrease with depth. The levels of detectable contaminantsdecreases with distance from the identified source areas such as sumps and loading areas.

• Barium and lead were detected at levels up to 341 and 171 0 ~g/g, respectively. Arsenic detectedat levels up to 15 ~g!g, chromium at levels up to 223 ~g!g, silver at levels up to 370 ~glg,

mercury and selenium at levels up to 4 and 2.53 ~g!g respectively. The areas with the highestmetals levels are the Building 3A-05-1 area and the area northwest of Building 3A-05-2.

• PCBs detected in one sample collected at the NPDES discharge point at Building 3A-05-2, atlevels less than) 0 ~g!g.

Line 5B · Two of eight sampling locations around Bldg. 5B-140-3, a pump house, reported RDX levelsabove 1000 ~g!g; two reported tetryl and HMX at levels between 100 and 500 ~glg. Lowerlevels of these explosives and 1,3,5-TNB, 1,3-DNB, and 2,4,6-TNT also found at Line 5B.Explosives contamination was found to a depth of four ft in areas adjacent to sumps. Explosiveconcentrations decreased rapidly from surface to four ft of depth.

• Lead was found near various buildings between J00 and 500 ~g/g, often near sumps. No metalsabove 100 ~glg were found helow two ft of depth.

Line 8 • No explosives were detected in soil samples collected throughout Line 8 and its associateddrainage ditches.

· Minor soil contamination by metals was reported in the RI, with localized, shallow (generally <two feet bgs) antimony and lead contamination around the two remaining production buildingsand the two destroyed production buildings. Data from the drainage pathways indicated nomigration of contaminants from these areas.

Line 800 Refer to Section 4.1.6.1

Jnert Disposal • Metals encountered as high as: barium (1240 ~glg), chromium (502 ~g/g), lead (51 ,000 ~g/g),

Area arsenic (117 ~glg), mercury (1.1 ~g!g), cadmium (31.2 ~g/g), silver (14 ~g/g), and selenium (100Ilglg). Decrease in detected levels with depth

Firing Site · Detectible levels ofradionuc1ides found at site, highest level at North Test Site.

Available data at Line 4B, Fly Ash Landfill, Construction Debris Landfill, and Building 600-86, and the Fly

Ash Disposal Area did not indicate significant contamination. Soil contamination at Line 800 is discussed

in Section 4.1.6.1 because the majority ofthe Line is in the Brush Creek Watershed.

5.1.6.2 Surface Water and Sediments. Previous investigation showed elevated levels of explosives

in the Long Creek drainage area. A sediment sample analyzed during the RI from along the discharge culvert

of industrial wastewater treatment Building 3A-70-1 contained RDX at 14,000 J.Ig/g. Other explosives as

well as metals (partiCUlarly chromium) were also detected in this sample. Another sample collected

approximately 160 feet southeast (downgradient) of this sample, was reported to have explosives in the range



of 100 to 500 ltg/g. Additional explosives screening conducted in this area detected explosives in the

drainage ditches southeast of this building. Another location where contamination was encountered was

approximately 250 feet southwest (downgradient) of Line 800 in an intermittent stream that drains to Long

Creek. No explosives were reported in the sediment sample but it did contain low levels of lead (17.0 ltg/g).

The surface water sample showed RDX at 2.01 ItgIL and lead at 2.82 ItgIL (JAYCOR 1996).

In Spring 1997, two locations (7N and 70 on Exhibit 4-2) along the downstream reaches Long Creek were

sampled, just upstream and downstream of the IAAAP boundary. No explosives were detected in either

surface water or sediment samples from these locations. Therefore, the Long Creek Drainage does not

appear to be impacted and is not of concern as an off-site migration route for site contaminants (Harza

1997a). Sampling results for surface water are shown in Table 5-5 and for sediments in Table 5-6.

Table 5-5. Results of Surface Water Sampling along Long Creek

Sampling Locations VOCs ("giL) SVOCs ("giL) Explosives ("giL) Metals Exceeding WQS

7N Methylene chloride (9.7B) None None None

70 None None None None

8 = Detected In blank as well as sample.

Table 5-6. Results of Sediment Sampling along Long Creek

Metals Exceeding

Sampling Locations VOCs ("glkg) SVOCs ("g/kg) Explosives ("glkg) Ecotox Threshold (mg/kg)

7NI (I ft) Methylene chloride (14.0B) None None None

701 (I ft) Methylene chloride (5.9B) None None None

701 (3 ft) None None None None

701 (4.5 ft) None None None None

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Fina/}


5.1.6.3 Groundwater. Parts ofboth Lines 3A and Line 800 are the areas in the Long Creek drainage area

where groundwater contamination is most notable. Table 5-7 summarizes detections of chemical parameter

groups in samples from the noted various facilities drained by Long Creek.

Table 5-7. Contaminants or Concern Detected in Groundwater

Location Metals Explosives VOCs SVOCs Sulfates Radionuclides

Line 3A x x x

Line 4B x

Line 5B x

Line 8 Not sampled

Line 800 x x x

Inert Disposal Area x x

Fly Ash Landfill/Disposal x x xArea

Construction Debris xLandfill

Firing Site x x

Bldg 600-86 x

The following paragraphs highlight results of sampling as reported by JAYCOR (1996). Concentrations

indicate the highest level reported within each facility or area.

At Line 3A, explosives were reported in five of eight wells. All concentrations reported were below 100

flglL (RDX at 18.7 flgIL and HMX at 3.31 flgIL). In groundwater samples from the portion of Line 800 that

may flow toward Long Creek, explosives' concentrations of 12.5 flglL for RDX and 2.56 flglL for HMX

were reported. At the Fly Ash Landfill, explosives were reported prior to 1991 at levels less than 10 flg/L,

but have not been reported since that time.

The maximum concentrations of metals reported at Line 3A included lead (20.2 flg/L), chromium (53.0

flgIL), and selenium (3.3 flgIL). At Line 58, the metal with the highest reported level was chromium, with

concentration less than 10 flgIL. In groundwater samples from the portion ofLine 800 that may flow toward

Long Creek, lead was reported at 2.17 flglL. Maximum concentrations of metals detected in groundwater

in the Inert Disposal Area included arsenic (16.0 flglL), chromium (35.0 flg/L), lead (9.87 flgIL), and

vanadium (68.4 flgIL). At the Fly Ash Landfill, detectable levels ofmetals were reported in five often wells,



including selenium (13.1 J.lgIL), chromium (21.1 J.lgIL), arsenic (5.65 J.lglL) and lead (2.93 J.lglL). Metals

concentrations reported at the Construction Debris Landfill included arsenic (3.84 J.lg/L), cadmium (55.7

J.lgIL), chromium (660 J.lgIL), lead (190 J.lgIL), silver (48.1 J.lglL), and mercury (0.64 J.lg/L). The maximum

values ofthe metals ofconcern an the Firing Site are chromium (443 J.lgIL), lead (1.95 J.lgIL) and arsenic (5.0

J.lg/L). Chromium was the metal with the highest reported value (15.0 J.lgIL) at Building 600-86. Others

metals reported include arsenic (3.1 J.lgIL), and lead (4.1 J.lglL).

VOCs reported at Line 3A included TCE (3.0 J.lglL) and chloroform (1.4 J.lglL). The only VOC

concentration above detection levels at Line 800 was I,I ,I-trichloroethane (3.5 J.lgIL). VOCs reported at the

Inert Disposal Area include I,I,I-trichloroethane (3.5 J.lg/L), I,I-dichloroethene (2.8 J.lg/L) and

trichloroethene (0.65 J.lg/L).

SVOCs at levels greater than detection level were reported at Line 4B, including bis(2)ethylhexylphthalate

(80.0 J.lgIL).

All eight wells at the Firing Site were reported to contain detectable levels of radionuclides. The highest

levels were recorded in wells surrounding the North Test Site, including potassium 40 (250 pC ilL), alpha

gross (24.8 pCilL), and beta gross (16.2 pCi/L).

5.1.6.4 NPDES Discharges. Permitted outfalls in the Long Creek drainage are presented in Table 5-8.

Table 5-8. Currently Permitted NPDES Discbarges to Long Creek

Outran Location Remarks Monitoring ParametersNo.

35 Une 3A, Bldg. 3A-70-2 Discharge from explosive loading Flow, pH, RDX+HMX. TNT, TSSoperations.

52 Line 5B, Bldg. 5B-140-3 Discharge from explosive loading Flow, pH, RDX+HMX, TNT, TSSoperations.

9 Bldg. 500-139 Treated effluent from main heating Flow, pH. TSSplant, consisting of coal pile runoff,boiler blowdown, and flyashleachate.

JAYCOR reports that explosives were recorded at highest levels in areas of permitted discharges (JAYCOR



1996). The effluent limits for the outfalls to Long Creek are shown in Table 5-9.

Table 5-9. NPDES Effluent Limitations

Concentration MassWastewater Season Average AverageParameters

30 Day Daily Max. Units 7Day 30 Day Daily Max. Units7Day

Flow Yearly 0.093 MGD

Total Yearly 20.00 40.00 mg/L 16.00 31.00 IbsldaySuspended 50.00(9)Solids

pH Yearly 6.00 9.00 STD

Trinitrotoluene Yearly 0.33 1.00 mglL 0.26 0.77 Ibs/day

RDX+HMX Yearly 0.75 2.25 mglL 0.58 I.75 Ibslday




1997b). Benthic sampling stations in the Long Creek watershed yielded 154 to 261 individuals and 8 to 16

macroinvertebrate taxa at each site. The number collected by station and the HBI tolerance values for all taxa

are presented in Appendix F. Pollution tolerance values, as used in the Rapid Bioassessment technique, are

provided by Hilsenhoff (1988). The greatest number of taxa were collected at Stations LC2 (16 taxa) and

Station LCTI (14 taxa). Only II taxa were collected at reference station LCI. Taxa that accounted for most

of the collected total were:

asellid isopods

chironomid midge larvae

hydropsychid caddis fly nymphs

physid snails

54%

12%

8%

11%

These taxa are fairly tolerant of pollution. Tolerance values vary from 0 (intolerant, sensitive) to 10 (highly

tolerant). Hydrophychids have a tolerance value of 4; chironomids 6; physids and asellids, 8.


March 21. 1998Page 5-10

5.2.2 Fish

The results of the collections at the two fish sampling stations on Long Creek revealed that fantail darter

were present at Station LC2, but did not inhabit the agriculturally impacted silty areas surrounding LC I.

Whole fish from LC2 were analyzed for explosives and biomagnifying COECs. The data provide no

evidence that aquatic biota are accumulating explosives or metals in Long Creek. All analyses of explosives

and metals in fish tissue were non-detects, with the corresponding MDLs (Tables 5-10 and 5-11), indicated

by the "<" symbol.

Table 5-10. Exnlosives Contamination in Fish in Lon2 Creek

Station LC2Field ID LC2-FLablD 5001-01Snecies Fantail

Analvte I"./k. wet wei.btl1,3,5-Trinitrobenzene <3121,3-Dinitrobenzene <2952,4,6-Trinitrotoluene <3142A-Dinitrotoluene <3162,6-Dinitrotoluene <2882-Amino-4,6-Dinitrotoluene <263

2-Nitrotoluene <291

3-Nitrotoluene <3424-Amino-2.6-Dinitrotoluene <283

4-Nitrotoluene <269RDX <273

Nitrobenzene <329

HMX <285Tet~1 <286

TableS-II. Metal Contamination in Fish in Lonp Creek

Station LC2Field ID LC2-FLablD 5001-01Snecies Fantail

Analvte Im./k. wet wei.ht'Mercurv <0.10


March 21, 1998Page 5·11

No pesticide analyses ofLong Creek fish were above the MDLs, except for dieldrin. The isolated presence

of dieldrin points to an agricultural source of the pesticide. No uptake of COEC pesticides/PCBs in Long

Creek is evidenced based on analytical results (Table 5-12).

Table 5-12. Pesticide Residues in Darters iu Lon" Creek

Station LC2Field 10 LC2·FLab 10 5001-01Soecies Fantail

Analvle hllUk" wei wei"bl)alpha-BHC <1.6

beta-BHC <1.5delta-BHC <1.6.amma-BHC <1.6Heotachlor <1.6Aldrin <1.6

Heolachlor eooxide <1.7

Endosulfan I <1.7

Dieldrin 29.04,4'-DDE <1.7

Endrin <1.6

Endosulfan II <1.6

4,4'-DDD <1.7

Endosulfan sulfate <1.6

4,4'-DDT <1.6

Methoxvchlor <1.7

Endrin aldehvde <1.7

Chlordane <3.3

Toxaohene <33.0

Arochlor 1016 <16.7

Arnchlor 1221 <27.2

Arochlor 1232 <15.8

Arochlor 1242 <16.7

Arochlor 1248 <16.5

Arochlor 1254 <16.2

Arochlor 1260 <16.4

Endrin ketone <1.7

Iowa Army Ammunition PlantEcological Risk Assessment Addendum fDrsft FinalJ

March 21, 1998Page 5-12

5.2.3. Small Mammals

Mammal tissues were collected at two locations in the Long Creek watershed to assess the risk to viability

of wildlife populations (Table 5-13). Weights shown in the table below are field weights of wet animals.

Table 5-13. Small Mammals from Lon.. Creek Watershed Analvzed for Selected COECs

Site Date Snecies Wei..ht 101 Lab Id. Analvtical Parameters

LCI 7/21/97 Peromvscus leucoDus 30 1091 H2, Pb, EXDIDsivesLCI 7/24/97 Peromyscus leucopus 44 1150 Hg, Pb, Fe. AI, Explosives, Pesticides

LC2 7/24/97 Peromvscus leucoDus 22 1089 H2, Pb, Fe, AI, Th. EXDIDsives

While three species of small mammals were captured in the watershed, white-footed mouse (Peromyscus

leucopus) was the most common species caught at the two trapping locations and was therefore selected for

analysis ofexplosives and selected metals at LC 1, the reference site for the watershed, and explosives, metals

and pesticideslPCBs at LC2, at Plant Road K. Minor accumulation of RDX iron, aluminum, and dieldrin

was found in mammal tissue from LC2 (Tables 5-14 thru 5-16).

Table 5-14. EXDlosives Contamination in Small Mammals from LoOl! Creek Watershed

Station LCI LCI LC2

Field ID 1150 1091 1089

LabID 5002-11 5002-10 5002-09

SDecies Mouse Mouse Mouse

Analvte (ul!!kl! wet weil!ht)

1.3,5-Trinitrobenzene <312 <312 <312

1,3-Dinitrobenzene <295 <295 <295

2,4,6-Trinitrotoluene <314 <314 <314



2-Amino-4,6-DinitrotoJuene <263 <263 <263



4-Amino-2,6-Dinitrotoluene <283 <283 <283


RDX <273 <273 1900

Nitrobenzene <329 <329 <329

HMX <285 <285 <285

Tetryl <286 <286 <286


March 21, 1998Page 5-13

Further, with the exception ofaluminum and iron, no metal residues in mammal tissue were above detection

limits. Concentrations of all metal residues in tissues are at typical levels. Mammals taken from the

reference station, LC I, had slightly higher concentrations of aluminum and iron than mammals from the

"impacted" station, LC2.

Table 5-15. Metal Contamination in Small MammalslLon Creek Watershed

Station LCt LCt LC2

Field ID 1150 1091 1089

LabID 5002·11 5002-10 5002·09

Snecies Mouse Mouse Mouse

Analvte (m"/k,, wet wei"btl

Aluminum 31.9 21.3 <5.0

Iron 146 142 74.7

Lead <2.5 <2.5 <2.5

Mercurv <0.10 <0.10 <0.10

Thallium <3.0

Table 5-16. Pesticide Contamination in Small Mammals/Lon.. Creek Watershed

Station LeIField ID 1150

LabID 5002-11

Snecies MouseAnaMe tu./k. wet wei"htl

alnha-BHC <1.6beta-BHC <1.5delta-BHC <1.6loamma-BHC <1.6Hentachlor <1.6Aldrin <1.6Hentachlor enoxide <1.7Endosulfan I <1.7Dieldrin 10.1

4,4'-00E <1.7Endrin <1.6Endosulfan II <1.64,4'-000 <1.7Endosulfan sulfate <1.64,4'-00T <1.6Methoxvchlor <1.7


March 21, 1998Page 5-14

Table 5-16. Pesticide Contamination in Small MammalslLone: Creek Watershed

Station LCIField ID 1150LablD 5002·11Species Mouse

Analvte h.21k2 wet wei2btl

Endrin aldehvde <1.7

Chlordane <3.3

Toxaphene <33.0

Arochlor 1016 <16.7

Arochlor 1221 <27.2Arochlor 1232 <15.8Arochlor 1242 <16.7

Arochlor 1248 <16.5

Arochlor 1254 <16.2

Arochlor 1260 <16.4

Endrin ketone <1.7

5.2.4 Soils

Surface soil samples were collected from two sites (LCI and LC2) in Long Creek drainage area for analysis.

No explosives were reported above the MOLs (Table 5-17). Minor concentrations of chromium and lead

were found in the soil (Table 5-18).

Table 5-17. Explosives Contamination in SoillLone: Creek Watershed

Station LCI LC2

Field ID LCI-S LC2·S

Lab ID 5000-03 5000-08

Analvte (Ile/ke drv weiehtl

1,3,5-Trinitrobenzene <312 <312

1,3·Dinitrobenzene <295 <295

2,4,6-Trinitrotoluene <314 <314

2,4-Dinitrotoluene <316 <316

2,6-Dinitrotoluene <288 <288

2-Arnino-4,6-Dinitrotoluene <263 <263

2-Nitrotoluene <291 <291

3-NitrotoJuene <342 <342

4-Arnino-2,6-0initrotoluene <283 <283

4-Nitrotoluene <269 <269

RDX <273 <273

Nitrobenzene <329 <329

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Fina/}

March 21, 1998Page 5-15

Table 5-17. EXDlosives Contamination in SoillLonll Creek Watershed

Station LCI LC2Field ID LCI-S LC2-SLablD 5000-03 5000-08

Analvte (n./k. drv weiehtlHMX <285 <285Totryl <286 <286

Tahle 5-18. Metal Contamination in Soil/Lone Creek Watershed

Station LCI LC2Field ID LCI-S LC2-SLab ID 5000-03 5000-08

Analvte (mvke)Chromium 3.2 7.6Lead M 16.9Mercury <0.10 <0.12Silver <0.52 <0.61

Thallinm <3.1 <3.6

Pesticides and PCBs in soil were non-detects except for DOE and PCB 1260 at LC2 (Table 5-19).

Table 5-19. Pesticide Contamination in SoillLonl! Creek Watershed

Station LCI LC2Field ID LCI-S LC2-S

Lah ID 5000-03 5000-08A.alvte (ne/ke drv wei.htl

alpha-BHC <0.57 <0.66

beta-BHC <0.54 <0.63

delta-BHC <0.57 <0.66

gamma-BHC <0.54 <0.63

Heptachlor <0.57 <0.67

Aldrin <0.55 <0.64

Heptachlor epoxide <0.58 <0.67

Endosulfan I <0.58 <0.67

Dieldrin <0.56 <0.65

4,4'-DDE <0.58 33.0

Endrin <0.56 <0.66

Endosulfan 11 <0.57 <0.66

4,4'-DDD <0.58 <0.67

Endosulfan sulfate <0.56 <0.65

4,4'-DDT <0.54 <0.63

Methoxvchlor <0.58 <0.67


March 21, 1998Page 5*16

Table 5-19. Pesticide Contamination in SoiVLon~Creek Watershed

Station LCI LC2

Field ID LCI-S LC2-S

Lab ID 5000-03 5000-08

Analvte ("Ilike dry weiehtlEndrin aldehyde <0.58 <0.68

Chlordane <1.1 <1.3

Toxaohene <11.5 <13.4

Arachlor 1016 <5.8 <6.7

Arachlor 1221 <9.5 <11.0

Arachlor 1232 <5.5 <6.4

Arochlor 1242 <5.8 <6.7

Arachlor 1248 <5.7 <6.7

Arachlor 1254 <5.6 <6.6

Arochlor 1260 <5.7 130

Endrin ketone <0.58 <0.68

5.2.5 Water

The available information on contaminants in surface water was limited to total pollutant concentrations.

Surface water was sampled on October 27, 1997 to speciate metals into dissolved and filtrable fractions

(Table 5-20). While aluminum and iron are largely present in particulate forms, barium, manganese, and zinc

are present largely in dissolved form. None ofthe measurements of metals shown in Table 5-20 exceed the

Iowa chronic or acute water quality standards for limited resource waters.

Table 5-20. Speciation of Metals in Surface Water - Long Creek Watershed (mglL)

LCt (reference) LC2 (Road K)


Aluminum <0.05 0.64 <0.05 0.071

Barium O. 11 0.11 0.13 0.069

Cobalt <0.005 <0.005 <0.005 <0.005

Iron 0.069 0.81 <0.05 0.16

Lead <0.025 <0.025 <0.025 <0.025

Manganese 0.13 0.14 0.031 0.037


March 21. 1998Page 5·17

Table 5-20. Speciation of Metals in Surface Water - Long Creek Watershed (mglL)

LCt (reference) LC2 (Road K)


Silver <0.005 <0.005 <0.005 <0.005

Thallium <0.03 <0.03 <0.03 <0.03

Vanadium <0.005 <0.005 <0.005 <0.005

Zinc 0.014 0.015 0.044 <0.005


The ecological risk within the Long Creek watershed is assessed separately for aquatic ecosytems and




Aquatic assessment endpoints for the IAAAP ERAA are the individual survival and viability of the state

listed threatened orangethroat darter and the health of the benthic macroinvertebrate community. Even

though the orangethroat darter is not present in Long Creek, other darter species are, and darter population

viability, in general, remains an appropriate assessment endpoint. To assess the risk to the darter

populations, levels of COECs in the water column were compared to RTV for chronic effects. Selected

RTVs were generally derived from multiple species tests, so their use is relevant to the orangethroat darter

as well as fishes in general. The health of the aquatic benthic community was measured using the Rapid

Bioassessment Protocol III (RBP) developed by the USEPA (Plafkin, et al. 1989).

5.3.1.1 Chemicals of Ecological Concern. Table 5-21 lists the maximum and 95% UCL total

concentrations ofthe preliminary COECs identified from screening the surface water and sediment databases

for the Long Creek watershed (Appendix A); these are the COECs used for the aquatic ecological risk

assessment in Long Creek watershed.


March 21, 1998Page 5·18

for the Long Creek watershed (Appendix A); these are the COECs used for the aquatic ecological risk

assessment in Long Creek watershed.

Table 5-21. Aquatic COECs for the Long Creek Watershed

Contaminant Maximum Concentration (J1g1L) 95% VeL (I1g/L)

RDX 17 (W) 0.935 (W)

Aluminum 16,400 (S) 8,105 (S)2,340 (W) 873 (W)

Barium 857 (S) 182 (S)836 (W) 127 (W)

Beryllium 1.6 (S) 0.93 (S)

Cobalt 44 (S) 10.1 (S)

Iron 440,000 (S) 23,100 (S)3,720 (W) 1,233 (W)

Lead 36 (W) 4.17 (W)

Manganese 5,990 (S) 786 (S)4.330 (W) 362 (W)

Mercury (biomagnifier) 0.247 (W) 0.126 (W)

Selenium 2.9 (S) 0.838 (S)

Thallium 260 (S) 10.3 (S)

Vanadium 47.9 (S) 25.3 (S)

Zinc 3,360 (W) 39.2 (W)

Benzo[defJphenanthrene II (S) 0.119 (S)

a-Chlordane (biornagnifier) 0.0495 (S) 0.0495 (S)

y-Chlordane (biomagniller) 0.03 (S) 003 (S)

1,I-dichloroethylene 13 (W) 0.60 (W)

The values shown in Table 5-21 are for all samples taken throughout the entire watershed, and include "hot

spots", that may, or may not, reflect potential exposure pathways to ecological receptors. One explosive,

twelve metals, and four chlorinated organic chemicals are listed on Table 5-21. These analyses represent

total concentrations in water or sediment. Of the seventeen COECs identified through the screening process,

three are biomagnifying COECs.

5.3.1.2 Exposure Assessment. Aquatic concentrations ofCOEC for exposure estimates were initially

taken as the 95% VCL of all surface water measurements in the watershed. This estimated the central

tendency of the COEC concentration as well as accounted for uncertainties in the accuracy of the


March 21. 1998Page 5·19

measurements. In estimating the 95%VCL, nondetect values were taken as 50% of the MOL. Exposure

concentrations represent total metals in surface water, as that is the nature ofJAYCOR's measurements. Vse

of exposure point concentrations calculated from total metal concentrations results in considerable

overprediction of exposures, as only a fraction of total metals are bioavailable. Dissolved metal

concentrations are a more appropriate measure of bioavailability. Laboratory toxicity tests are conducted

under conditions favoring toxicant bioavailability; as lab dilution waters contain low concentrations of

suspended solids and organic carbon. Standard test methods require high purity dilution water. Recognizing

this, dissolved COEC concentrations should be used in aquatic ecological risk assessments (WERF 1996).


operational definition for the dissolved fraction (see Table 5-20). Ten metals were speciated in this manner.

This allowed estimation of exposure concentrations as dissolved metals for those ten elements. In other

cases, total pollutant concentrations were used.

No biomagnifying COECs are found above MDLs in darter tissue.

5.3.1.3 Risk Estimates. Aquatic RTVs were presented in Section 4.3.1.3. Hazard quotients computed

as the exposure point concentration (95% VCL) in Long Creek divided by the aquatic RTV for NOAEL are

for each aquatic COEC in the Long Creek drainage are presented in Table 5-22.

Table 5-22. Aquatic Hazard Quotients for Long Creek Watershed

COEC Exposure Point Concentrations (ug/L) RTV Hazard Quotients

Aluminum 50 3288 0.02

Iron 50 1300 0.04

Lead 4.174 18.9 0.2

Thallium 7.387 12 0.6

Barium 130 4 33

Beryllium 2.676 57 0.05

Mercury 0.126 120 0.001

Selenium 2.134 88.3 0.02

Zinc 44 60 0.7

Cobalt 5 23 0.2

Manganese 31 120 0.2

Vanadium 5 20 0.3

Benzo[def]phenanthrene 1.4 2000 0.0007

Iowa Army Ammunition PlantEcological Risk Assessment Addendum fOraft Final)

March 21, 1998Page 5-20

Table 5-22. Aquatic Hazard Quotients for Long Creek Watersbed


alpha-Chlordane 0 1.6 0

gamma-Chlordane 0 1.6 0

4,4'-DDE 0 0.013 0

4,4'-DDT 0 0.013 0

I,I-Dichloroethylene 0.601 25 0.02

HQ's greater than one would be expected to present significant risk; this is notably apparent for barium.

Barium HQ values are greater than one, indicating a possibility of adverse effects. This value is based on

dissolved barium concentration in surface water, as measured on October 27, 1997. Background

concentrations of metals were not part ofthe data screening algorithm shown in Exhibit 3-2. Based upon

eight samples, JAYCOR (1996) defined background concentrations for total barium concentration torange

from III to 227 ~gIL. The 950/0UCL total barium concentration for Long Creek is 127 ~g/L, and is within

the expected range for background. Hence, while the dissolved EPC for Ba may exceed the RTV by a factor

of 33, the potential for adverse effects is due to natural sources.

Biomagnif)ring COECs do not represent any significant risk to darter populations. Concentrations of these

chemicals could not be detected and do not appear to be significantly influencing the food chain.

5.3.1.4 Aquatic Macroinvertebrate Community Structure. Physical habitat at sampling sites

throughout the Long Creek watershed were generally similar, but due to the agricultural activities offsite,

the upstream reference station, LC I, had greater amounts of silt in substrate areas. There were three

sampling locations on tributaries to Long Creek, referred to as LCT], LCT2 and LCD (Exhibit 3-1).

Species and tallies for each sampling station are provided in Appendix F.

Results of the RBP assessment are tabulated below. Compared to the reference station, LC2 and LCTI are

considered unimpaired and benthic community structure is not exhibiting ecological stress, as measured by

the RBP. Stations LCn and LCD were rated as slightly impaired, generally because the tributaries had few

EPT taxa (Table 5-23). (This may reflect increasing diversity from headwaters to downstream rather than

anthropogenic effects.)


March 21, 1998Page 5·21

Table 5-23. Rapid Bioassessment Protocol III for Long Creek Watershed

Station No. LCTt LCT2 LCT3 LCI LC2

Source of Sample Tributary Tributary Tributary Long Cr. Long Cr.MI· Species Richness 14 9 8 II 16

Biological Condition Score 6 6 4 6 6

M2 - HBI (modified) 6.6 7.6 7.5 7.5 4.6


M3 -ScraperslFiltering Collectors 123% 17% 5400% 32% 39%Biological Condition Score 6 6 6 6 6

M4 - EPT/Chironomidae 106% 267% 21% 214% 184%


M5 • % Dominant Taxon 41% 89% 50% 75% 40%Biological Condition Score 0 0 0 0 0

M6 - EPT Index 3 2 2 3 5


M7 - Community Loss 0.07 0.67 0.50 0.00 0.25


M8 - Shredders/Total 36% 96% 54% 60% 10%


% Comparison to Reference Score 90% 81% 62% 100% 88%

Biological Condition Category UnimpairedSlightly Slightly

Reference UnimpairedImpaired impaired

5.3.1.5 Uncertainty. Our evaluation of uncertainty in the aquatic risk assessment for the Long Creek

watershed can be summarized as:

• The uncertainty of the HQ for biomagnification and adverse effects on darter reproduction is

considered to be low. Field measurements of tissues residues are a more accurate assessment

technique than modeling, and no biomagnifying compounds were detected in darter tissues.

• Uncertainty of the RBP is also considered to be low. The technique is widely used in the industry

for evaluation ofaquatic impacts and is considered a reliable tool by regulatory agencies in nearly

all states. Iowa DNR routinely includes stream bioassessments in new NPDES permit as a

monitoring requirement. The RBP III includes eight metrics. and impacts not assessed by one metric

should be evaluated by another. Hence, the benthic community assessment provides the greatest

level of accuracy with the least uncertainty.


March 21. 1998Page 5-22

• The uncertainty associated with the aquatic RTVs varies. Many of the Tier II SCVs are based on

few tests. For example, the RTV for barium is based upon a single chronic toxicity test ofDaphnia

magna, which is not a fish (Suter and Tsao 1996). The Tier II procedures are conservative estimates

and were developed to protect all Great Lakes aquatic life.

5.3.1.6 Summary of Aquatic Risks. Evidence indicating aquatic risks from IAAAP operations on the

Long Creek watershed are minimal. The benthic community structure endpoint is considered the most

reliable measure ofaquatic ecosystem health in the aquatic risk assessment study with the least uncertainty.

The stream is essentially unimpaired or slightly impaired and does not show adverse effects from IAAAP

operations. The darter viability assessment does not indicate probable risks.



the viability of wildlife populations. Body burdens of COECs in small mammals collected in floodplain

habitats were measured and were evaluated in the context of existing toxicity information. Additionally,

because offederallisting as a threatened species, the viability of the bald eagle (Haliaee/us leucocephalus)

was assessed. To assess the health of the vascular plant communities potentially affected by chemical

contamination, the site quality indices of such communities (especially on the species richness metric) as

determined by Horton e/ at. (1996), was the measurement endpoint.


Long Creek watershed soils database including five explosives, six metals, three base neutral organics and

five pesticides (Appendix A).

Table 5-24. Terrestrial COECs for the Long Creek Watershed

Contaminant Maximum Concentration (mglkg) 95% VCL (mg/kg)

1,3,5-trinitrobenzene 21 1.42

2,4,6-trinitrotoluene 25,000 119

2,4-dinitrotoluene 13.2 0.454

HMX 13,000 12

RDX 75,000 18.7

Iowa Army Ammunition PlantEcological Risk Assessment Addendum IOraft Final)

March 21. 1998Page 5-23

Table 5-24. Terrestrial COECs for the Long Creek Watershed

Contaminant Maximum Concentration (mg/kg) 95% VCL (mg/kg)

Aluminum 41,400 12,290

Chromium 2,800 36.2

Iron 170,000 21,082

Lead 51,000 204

Silver 370 1.40

Thallium 230 18.7

Benzo[defjphenanthrene 2 0.167

Bis(2-ethyIhexyI)phthlate 6.2 2.324

Di-n-butyl phthlate 6.2 0.644

4,4'-DDE (biomagnifier) 0.034 0.014

4,4'-DDT (hiomagnifier) 0.05 0.023

a·Chlordane (biomagnifier) 0.0144 0.0144

y-Chlordane (biomagnifier) 0.0186 0.0186

I, I. I-trichloroethane 0.83 0.408

All data used to generate the table were taken from the JAYCOR database provided by IAAAP to Harza.

The values shown in Table 5-24 are for the entire watershed, and include "hot spots", that may, or may not,

reflect potential exposure pathways to ecological receptors.

In Section 3.6, the process used to screen the contaminant database and to identify the preliminary chemicals

of ecological concern (COECs) was described. Table 5-21 lists the COECs identified from screening the

soils database; these are the COECs used for the terrestrial ecological risk assessment for the Long Creek

watershed. COECs for the Long Creek terrestrial risk assessment include five explosives, six metals, and

eight non-explosive organic chemicals.

5.3.2.2 Exposure Estimates. Section 4.3.2 and Appendices Band C provide details on computational

methods used to estimate exposures to terrestrial receptors. The assessment endpoint for terrestrial high

trophic level consumers exposed via their diet is reduced reproductive success. The measurement endpoint

is body burdens of COECs in small mammals. Soils and mammal tissues were collected at specified

locations in the Long Creek watershed to assess the risk to viability of wildlife populations. The white

footed mouse was principally used to estimate the COEC body burdens in small mammals in the Long Creek

watershed. The white-footed mouse lives primarily in wooded areas, brushy borders or fence rows. Nests


March 21, 1998Page 5·24

may be in tree cavities, old bird or squirrel nests, or underground beneath protective cover. Its home range

is generally small, about one-fifth acre. Preferred foods of white-footed mice include insects, seeds and

fruit, with the relative amounts depending upon availability (Schwartz and Schwartz 1981).

The likely body burdens of those contaminants that tend to biomagnify in a federally-listed threatened

species, the bald eagle were estimated utilizing the body burdens of contaminants in small mammals and

darters.

Table 5-25 gives the dose estimates ofterrestrial COECs to white-footed mice at two sites in the Long Creek

watershed. LC I is upstream of the IAAAP and is a reference station; LC2 is at Road K. Full tabulation of

the computations are reprinted in Appendix C.

Table 5-25. Estimated Mouse Doses (mglkgld)

COEC LCI LC2

1,3,5-Trinitrobenzene 0.2 1.0

2,4,6-Trinitrotoluene 0.01 0.003

HMX 0.05 0.2

RDX 0.2 0.2

2,4·Dinitroto)uene 0.0002 0.0007

Aluminum 50 0.002

Chromium 0.08 0.1

Iron 70 0.002

Lead 0.2 0.2

Silver 0.02 0.02

Thallium 0.006 0.007

Benzo[del]phenanthrene 0.0002 0.00006

Bis(2.ethylhexyl) phthalate 0.003

Di·n·butyl phthalate 0.0005

alpha-Chlordane 0.000003 0.000003

4,4'-DDE 0.0002 0.0004

4,4'-DDT 0.0001 0.000002

gamma-Chlordane 0.000003 0.000003

1,1, I·Trichloroethane 0.0004 0.00004

Within the Long Creek watershed, biomagnifying terrestrial COECs passing the prescreening process include


March 21, 1998Page 5-25

DDT (and metabolites) and chlordane. The concentrations ofthese chemicals were measured in eagle prey

(Tables 5-12 and 5-16) detectable residues were found. To confirm that bio-magnification of COECs is not

posing significant risk to special resources, the potential doses of these pesticides to the bald eagle was

estimated using doses based on 50% ofMDL (Table 5-26). Full tabulation ofthe computations are reprinted

in Appendix C.

Table 5-26. Estimated Doses to Bald Eagle of Biomagnifying COECs (mglkg-d)

COEC LCI LC2

alpha-Chlordane 0.0000007 0.00001

I£amma-Chlordane 0.0000007 0.00001

4,4'-DDE 0.000003 0.00002

4,4'-DDT 0.000001 0.000005

5.3.2.3 Effects. NOAEL values shown in Table 4-30 for white-footed mouse and for bald eagle were

used to estimate the effects ofthe chemicals of concern. Reference Toxicity Values were taken from the

literature scaled to white-footed mice or eagles using the body weight ratio method of Sample et al. (1996).


below. Appendix C provides the basis for these risk estimates.

White-footed Mouse. Table 5-27 provides NOAEL values and hazard quotients for risk to white-footed

mice. As many of these chemicals have different mechanisms of toxicity, summing them for estimation of

a hazard index is not appropriate.

Table 5-27. NOAEL Values and Hazard Quotients for White-Footed Mice

Hazard Quotient

COEC NOAEL (mg/kg/d) LCI LC2

1,3.5~Trinitrobenzene 57.4 0.003 0.02

2,4,6-Trinitrotoluene 3.00 0.003 0.001

RDX 7.9 0.02 0.02

HMX 115 0.0004 0.002

2,4-Dinitrotoluene 13.5 0.00002 0.00005


March 21, 1998Page 5-26

Table 5-27. NOAEL Values and Hazard Quotients for White-Footed Mice

Hazard Quotient


Aluminum 2.09 22 0.001

Chromium 6.55 om 0.02

Iron 147 0.5 0.00001

Lead 16.0 0.01 0.01

Silver 0.11 0.1 0.2

Thallium 0.02 0.4 0.5

Benzo[det]phenanthrene 75.0 0.000003 0.0000008

Bis(2-ethylhexyl) phthalate 19.8 0.0001

Di-n-butyl phthalate 594 0.000001

alpha·Chlordane 5 0.000001 0.000001

4,4'·DDE 1.60 0.0001 0.0003

4,4'·DDT 1.60 0.00007 0.000001

gamma·Chlordane 5 0.000001 0.000001

I, I, I-Trichloroethane 1,123 0.0000003 0.00000004

No COECs appear to present any significant risk to small mammals at LC2. The reference site, LC I, has

apparent risk to white·footed mouse from aluminum. The JAYCOR database has no measurements of soil

aluminum or iron and exposures to these metals from mouse food or soil ingestion are not included in LC2.

Background soil aluminum concentrations at IAAAP were defined by JAYCOR to be as high as 22, I00

mg/kg. At LCI, soil aluminum has a 95%UCL concentration of 14,744 mg/kg, hence it would appear that

any risks from aluminum at LC I is due to natural causes.

Bald Eagle. NOAEL values and hazard quotients (HQ) for biomagnitYing COECs consumed by bald eagles

in the Long Creek watershed are presented in Table 5-28. HQs at both LC I and LC2 are considerably below

the level of concern. Full tabulation of the computations are reprinted in Appendix C.

Table 5-28. NOAELs and HQs for Bald Eagles

Hazard Quotient


alpha-Chlordane 0.4145 0.000002 0.00002

gamma-Chlordane 0.4145 0.000002 0.00002

4,4'·DDE 0.0030 0.001 0.005


March 21, 1998Page 5-27

14,4'-DDT 0.0030 0.0004 0.002

With the exception of4,4'-DDE in LC2 soils found to be 33 Ilglkg, no biomagnifying COECs were detected

in fish, mammal or soil matrices at LCI or LC2, In use of 50% of the MDL for COEC concentration, it does

not appear that bald eagle viability or reproductivity is at any significant risk in the Long Creek watershed.

The exposure modification rate (EMR) is 0.05. This estimate is conservative, as bald eagles have a large

feeding range and will not limit themselves to a small area such as the Long Creek drainage. Feeding by

bald eagles at Mathes Lake has been reported, but it is not likely that more than about 5% of an individual

bird's diet would be supplied by the Long Creek watershed.

5.3.2.5 Vascular Vegetation Community Structure. Horton et al. (1996) prepared a forest

community quality assessment as part of their study. Horton et al. 's forest community quality index was

based on vascular plants and bryophytes, and was composed of six metrics:

I. Err vasc =number ofspecies offederal and state endangered or threatened vascular plants,


2. Err bryo = number ofbryophyte species previously undocumented or recorded from fewer


3. Rare vasc = number of species of vascular plants new to, and/or considered rare in Des


4. Rare bryo = number of species of bryophytes new to Des Moines County

5. Spp Rich vasc = species richness of indigenous vascular plants

6. % indig =percentage of flora comprised of indigenous vascular plant species

Horton et al. inventoried 30 forest community sites in, or near, the IAAAP and scored them according to the

above six metrics. The numerical results of the surveys for each of the six metrics for all 30 sites were

divided into five equal classes and each class (and the numerical values in that class) assigned a class score

between 0 and 5. A site quality index for each locality was then the sum of the class scores. Fifteen of their

study sites were in the Long Creek watershed. The numerical values of each metric and its class score (in

parentheses), and site quality indices for these sites are given in Table 5-29. Sites where data were

insufficient to calculate a metric are denoted (10) for that metric.

Jowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Fina/)

March 21. 1998Page 5-28

Table 5-29. Relative Quality of Forest Communities, Long Creek Watershed, IAAAP

Locale Site EIT vase Err Rare vase Rare bryo Spp Rieh vase 0./0 indig Indexbryn

SE ofehurch LC1 0 0 3 (I) I (I) 97 (3) 94 (4) 9Wof Stump Lake 0 0 0 0 40 (I) 85 (I) 2Eof Stump Lake 0 0 0 0 56 (2) 86 (2) 4Tributary Sof Stump Lake 0 0 I (I) 0 48 (I) 87 (2) 4

Trib EofRd C 0 1(I) 5(2) 2 (I) 105 (3) 96 (5) 12E&WofRdA 0 0 2 (1) 0 10 10 10

WofRoad M 0 0 0 0 10 10 10

Eof Road M 0 0 1(I) 0 10 10 10

Mathes Lake Peninsula 2 (2) 0 8(2) 1(I) 124 (3) 95 (5) 13

SW shore Mathes Lake 1(I) 2 (3) 7(2) 5 (3) 96 (3) 93 (4) 16

Trib Y2 Mi E of Long Creek 0 I (1) 6 (2) 1(1) 86 (2) 95 (5) 11

WSide Nof Road K 1(I) 2 (3) 10 (3) 9 (5) 119 (4) 98 (5) 20

ESide NofRd K LC2 0 1(I) 4 (I) 3 (2) 85 (2) 94 (4) 10

Sof Road K 4(5) 3(5) 15 (4) 4 (2) 159 (4) 90 (3) 23

ESide SofRd K 0 1(I) 7(2) 10 (5) 125 (3) 94 (4) 15


condition ofa site in comparison with other sites within and beyond the Long Creek watershed. Horton et

al. Classified sites having a site quality index (SQI) greater than or equal to 20 as "exceptional," and sites

within an SQI of 10-19 as "significant." Sites with SQI scores of less than 10 were "considered of marginal

value as natural areas." Although the site quality index was developed and used by Horton et al. to define

the value of a site as a natural area, it is assumed for the risk assessment that sites having "exceptional" or

"significant" site quality indices are not degraded by chemical contamination. However, it is also recognized

that sites identified as "marginal natural areas" may have been altered from a "natural state" by factors other

than chemical contamination. Foremost among such factors would be land clearing and agricultural

activities on the lAAAP property.

As seen in Table 5-29, the sites adjacent to Road K, where LC2 is located, represent some of the highest

quality forest in the Long Creek watershed and the entire IAAAP (Horton et al. 1996). Forest species

richness and the percentage of indigenous flora are quite high at those sites. Horton et al. attributed this to

the relatively to the large size, and undisturbed nature ofthe forest tracts in that area (Exhibit 3-1). Although

LC2 has a site quality index of 10 (and is below the "natural quality" of the surrounding sites), it is,


March 21, 1998Page 5-29

nonetheless, a "significant" natural area and thus is considered to be unaffected by chemical contamination.

Site LCI, the reference station, has a site quality index of9 (principally on the basis of lack of bryophytes).

However, given the higher species richness and same percentage of indigenous flora at LC I as found at LC2,

the stations are likely equivalent from an ecological perspective. As IAAAP continues to operate and

maintain its munition manufacturing facilities and agricultural activities, to develop new facilities or to

decommission antiquated ones, maintaining or increasing forest tract size can be used as a criterion for

decision-making, thereby mitigating risk to this community.

5.3.2.6 Uncertainty. Several assumptions or procedures used in this risk assessment are sources of

uncertainty. The uncertainty related to the forest community quality index prepared by Horton el al. is

considered to be moderate to low. The inclusion of six metrics in the index broadens its reliability as an

indicator of ecological stress.

The prescreening process using detection frequencies and benchmark criteria is not a significant contributor

to uncertainty. All the data in the watershed, including "hot spots" not normally considered ecological

pathways, were used to narrow the number of chemicals to the COEC list addressed in this chapter. The

procedure should not have eliminated any COECs nor included chemicals that were ofno ecological concern.

The terrestrial exposure assessment was limited to two stations in the watershed, one of which was intended

to serve as a reference. Characterization of the watershed on the basis of two stations poses some

uncertainty. While the number of sources of contamination in the Long Creek watershed, previous studies

on ecological stress, and budgetary factors were contributors to the selection of two exposure sampling

stations, this does increase uncertainty for the basin.

Several other factors in the exposure assessment contributed to uncertainty. In general, we are confident in

our findings because:

• With the exception of4,4'-DDE in LC2 soils (found to be 33 llg/kg), no biomagnirying COECs were

detected in fish, mammal or soil matrices at LC I or LC2.

• In all cases, we attempted to be conservative in our assumptions in order to minimize uncertainty.


March 27. 1998Page 5·30

• Contaminant intake factors accounted for the diversities ofdiet in both white-footed mouse and bald

eagle. While we measured contaminant concentrations in two ofthe three main constituents ofeagle

diet (mammals and fish) we did not measure contaminant concentrations in waterfowl, generally

about 16% ofa bald eagle's food intake. COEC intake via waterfowl consumption was modeled and

therefore has a higher level of uncertainty associated with it than field measurements. Also, there

is some uncertainty that levels of COECs in darters are representative of levels in larger fish eaten

by eagles. Use ofCOEC concentrations equal to 50% of the MOL did not contribute significantly

to uncertainty, as the risk estimates are quite low and, even using 100% of the MOL would not have

increased the hazard quotient sufficiently to indicate adverse risk.

• The exposure modification rate used for bald eagle was 5%, a conservative number for the Long

Creek watershed, as it is not likely the birds are feeding there 5% of the time during a given year.

Bald eagle have a large feeding range and will not limit themselves to a small area such as the Long

Creek drainage. Feeding by bald eagle at Mathes Lake has been reported, but it is not likely that

more than about 5% of an individual birds diet would be supplied by the Long Creek watershed.

Oose estimates are likely high, as we assumed that COECs undetected in darter and mammal tissue

were equal to 50% of the MOL.

The effects assessment is conservative. NOAEL RTVs rather than LOAEL or other endpoint were used in

the estimates. This reduces uncertainty about individual survival of species of special concern.

5.3.2.7 Summary of Terrestrial Risks. There is no evidence for adverse effects on the terrestrial

ecosystem of Long Creek watershed from lAAAP operations. No COECs appear to present any significant

risk to small mammals at LC2. The reference site, LCI, has apparent risk to white-footed mouse from

aluminum, but this is due to natural causes, not IAAAP operations.

With the exception of 4,4'-OOE in LC2 soils found to be 33 ppb, no biomagnifying COECs were detected

in fish, mammal or soil matrices at LC I or LC2. In using 50% of the MOL for COEC concentration, it does

not appear that bald eagle survival or reproductivity is at any significant risk in the Long Creek watershed.

The EMR is 0.05. This estimate is conservative, as bald eagle have a large feeding range and will not limit

Iowa Army Ammunition PlamEcological Risk Assessment Addendum (Draft Final)

March 21, 1998Page 5-37

themselves to a small area such as the Long Creek drainage. Feeding by bald eagles at Mathes Lake has been

reported, but it is not likely that more than about 5% ofan individual birds diet would be supplied by the

Long Creek watershed.

Forest community in the Long Creek watershed is adversely affected by land management activities in many

areas north of Mathes Lake. Forest communities in the vicinity of the lake, and south to the IAAAP

boundary represent some ofthe highest quality forest in the Long Creek watershed and the entire IAAAP.

Forest species richness and percent indigenous flora are quite high. Horton et al. attributed this to the

relatively to the large size, and undisturbed nature of the forest tracts in that region. Based on the quality

of the vegetation at LC2, the site is unaffected by chemical contamination.

10 wa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Fina/}

March 21, 1998Page 5-32

6.0 SPRING CREEK WATERSHED



Spring Creek originates off-site, just north of the Burlington Northern Railroad easement, drains the

easternmost portion of the lAAAP and exits the site at the southeastern corner. Its drainage area within the

site boundaries covers approximately 3,900 acres. The creek is intermittent and is seasonally dry within the

lAAAP limits. At the southeastern boundary of the site, the Spring Creek flood plain is approximately 400

feet wide and is incised approximately 90 feet into glacial till. Spring Creek flows off-site at the southeastern

comer and continues in a south-southeasterly direction approximately 10 miles, where it then flows directly

into the Mississippi River. According to JAYCOR (1996), there are no flood maps or hydraulic profiles

published for Spring Creek.


Land uselland cover in the Spring Creek watershed is primarily upland forest and agriculture. Exhibit 3- I

is a map of land use at the lAAAP, and areas of each classification for this basin are presented in Table 6-1.

Table 6-1. Sorin!! Creek Watershed Land UselLand Cover

Land Use/Land Cover Acrea2:e Percenta2e

Upland Forest 1,386 36%

Flood plain Forest 296 8%

Old Field 590 15%

Other Wetland 27 1%

Agriculture 1,100 28%


Open Water, Pond/Lake 7 0%

Residential 0 0%



Total 3,892 100%

IAAAP fenced compound areas contain most of the buildings and are mainly upland habitats surrounded



principally by non-native introduced vegetation. There are also large areas ofcrops, leased to local farmers.

The natural vegetation community is predominantly temperate deciduous forest, in its early successional sere,

which occurs on the slopes and lowlands along the stream.

In 1996, an inventory and assessment of habitats and biota of the 1AAAP was published (Horton et al.).

While their objective was to assess the entire facility, the focus was on natural areas along creeks and

drainageways, where temperate deciduous forest predominates. At lAAAP, the current flood plain forest

is characterized by the dominance ofcottonwood (Populus deltoides), black willow (Salix nigra), sycamore

(Platanus occidentalis), honey locust (Gleditsia triacanthos), green ash (Fraxinus pennsylvanica), northern

hackberry (Celtis occidentalis), elm (Ulmus spp.), poison ivy (Rhus radicans), grape (Vitus spp.), multiflora

rose (Rosa multiflora), brambles (Rubus spp.), and numerous species offorbs, grasses and sedges (Horton

et al. 1996).


The bald eagle (Haliaeetus leucocephalus), a threatened species, has been recorded to feed in the Long Creek

watershed and individuals likely pass through the Spring Creek watershed from time to time. In their survey

ofIAAAP, Horton et al. (1996) found no federally listed endangered species within the IAAAP boundaries,

but did record six state-threatened species of plants and one state-listed threatened fish species at the site.

Ofthese, only two species were found in the Spring Creek watershed. These are listed below (Table 6-2).

The presence ofsignificant numbers of orangethroat darter (Etheostoma spectabile) throughout Spring creek

was confirmed by Harza ecologist during the field program. The locations of biological resources of special

concern within the Spring Creek watershed are provided in Table 6-2.

Table 6-2. Protected Species in the Spring Creek Watershed

Locality Organism

S of Plant Road P to Middle Augusta Road. sharpwing monkey-flower (Mimulus alatus)Sec. 10, T69N, R3WLowland/floodplain forest, adjacent to creek

Plant Road P crossing to Explosive Disposal Area. orangethroat darterSec. 4, T69N, R3W

Plant Road P crossing. orangethroat darterSW 114 of SE 114, Sec. 3, T69N, R3W



Table 6-2. Protected Species in tbe Spring Creek Watershed

Locality Organism

Plant Road K crossing. orangethroat darterSec. 15. T69N, R3W

Outside SE comer IAAAP, Hunt Rd Bridge crossing. orangethroat darterSec. 23, T69N, R3W


Spring Creek originates north of the IAAAP, flows through the plant, then enters the Mississippi River to

the southeast. Spring Creek is deeply incised into the glacial drift underlying upland areas at IAAAP,

draining most of the Explosive Disposal Area (EDA), the Ammunition Box Chipper Disposal Pit area and

the east parts of Yards C and 0, exiting the property at the southeast corner. Beneath upstream reaches of

the creek, bedrock is relatively high, locally occurring at depths less than 25 feet, but is not known to be

exposed. The bedrock surface beneath the drift then slopes downward to the southwest and the south, with

drift thicknesses in excess of 85 feet locally. Groundwater flow in the shallow drift within the Spring Creek

drainage parallels surface topography toward the creek and to any significant tributaries. Groundwater flow

within the upper bedrock is generally to the east and southeast.

6.1.5 Facilities

Before Spring Creek enters IAAAP property, the stream receives treated municipal sewage effluent from

the City of West Burlington, Iowa. Facilities in the Spring Creek drainage area include the EDA,

Ammunition Box Chipper Disposal Pit, Fire Training Pit, Contaminated Waste Processor (CWP), Explosive

Waste Incinerator (EWI), North Burn Pads, North Burn Pads Landfill, PCB Roundhouse Transformer

Storage Area, and West Burn Pads. Briefdescriptions of the facilities in the watershed, as described in the

RI report (JAYCOR 1996), are contained in Table 6-3.

Iowa Armv Ammunition PlantEcological Risk Assessment Addendum (Draft Final)


Table 6-3. Facilities in Spring Creek Watershed

Size! Period of ContaminantsFacility Bldgs Operation Function WastewaterlW8sfe of Concern

Explosive 12 acres Until 1982 Open burning of explosives- Surface runoff from western ExplosivesDisposal Area contaminated metals, portion goes directly to Spring Metals

propellants, explosives, and Creek, eastern portion to a svacspyrotechnic contaminated tributary of Spring Creek.materials.

Contaminated Housed 1982 to Flashes or bums materials Ash is drummed and placed in ExplosivesWaste Processor in Bldg. present that have come in contact RCRA accumulation area Metals

BG- with explosives or other pending TCLP results. CWP199-2. energetic substances, generated wash water collected

including equipment, pipe, in floor trenches and pumpedsteel, empty cartridge cases into 1,200 gallon sump onand projectiles, and lumber. south side of building and

transported to Line 2 fortreatment.

Explosive Waste Within 1981-1990 Incineration of sump scrap Residue and ash is drummed, svacsIncinerator Bldg. and as and waste explosives that labeled, transferred to the

BG- needed cannot be reused or resold to RCRA accumulation area,199-1 in (short-term an off-site vendor. EWI is a CWP, and managed as 0003EDA operation permitted RCRA facility. waste. Wastewater is pumped

limit) into a sump and transported toLine 2 for treatment.

Ammunition Box 120 by 3-month Small burial site where Shredded wooden ammunition ExplosivesChipper Disposal 40 by 8 period shredded wooden boxes, primarily 90-millimeterPit ft between ammunition boxes were cartridge boxes.

1972 and reportedly buried.1975

West Bum Pads 2 burn 1949-1982 Bum pads, landfill, bum West Bum Pads Landfill Explosivespads- 50 (pads, cages, burn cage ash received residue from pads and Metalsby 15ft; cages, and disposal landfill. Explosives various types of solid waste. svacslandfill- Bum Cage contaminated metal parts Burn Cage Ash Disposal vacs200 by Ash flashed at pads, disposed of Landfill received residual ash300 ft; 3 Disposal or sold as scrap. from bum cages. Discardedcages- Landfill) Salvageable metal parts materials were put on ground30 by 60 1950-1975 stored here presently. Cages and covered with earth at bothft (WestBum used for incineration of inert "landfills".

Pads and explosive-contaminatedLandfill) packaging.

North Bum Pads 2 pads- 1968-1972 Burning of lead azide and Surface run-off to southeast Metals20 by 50 gun powder. A 275-gallon toward unnamed tributary offt each diesel fuel station currently Spring Creek.

located at site, including anAST.

Fire Training Pit 40 by 60 1982-1987 Fifty-five gallons drums of Remedial Action? Metalsby 2 ft solvents or fuels placed in svacs

pits, set ablaze, extinguished vacsby firefighters.

PCB Large, Prior to Storage of unused In 1980, all transformers with PCBsRoundhouse 11at, 1980 to transformers in yard on > 500 ~g/g PCBs moved insideTransformer graded present ground surface. warebouse; 1987, allStorage Area area transformers with> 50 Ilg/g

PCBs moved inside.



Table 6-3. Facilities in Spring Creek Watershed

Sizel Period of ContaminantsFacility Bldgs Operation Function WastewaterlW85te of Concern

North Bum Pads 3/4 acre Prior to Stored residue from the Flashed cans and containers ExplosivesLandfill 1980. North Bum Pads. from North Bum Pads. Now Metals

capped and closed. Contentsremoved in J980 to InertDisposal Area.


6.1.6.1 Soils. Soil contamination at facilities in the Spring Creek drainage is summarized in Table 6-4.

Data are from the RI report (JAYCOR 1996), except where referenced.

Table 6-4. Soil Contamination at Spring Creek Watersbed Facilities


Explosive Disposal · RI screening indicated explosives contamination. Pad centers, areas near culverts, and areasArea where pools of surface water develop in the drainage ditches reported the highest explosive

levels. The highest levels of contamination in the soils at the site appears to be confined tothe upper three feet.

0 Metals were detected mostly at low levels. Lead reported at the highest levels (between 100and 500 llg/g in the drainage ditch that runs southeast along the pad entrances.

0 Surficial (0.5 feet or less) soil in the drainage ditches near the 8 burn pads containedelevated levels of SVOCs.

West Burn Pads · The RI indicated the widespread presence explosives in surficial soils and drainageways atR24. Explosives appear to be at the highest concentrations J75 feet northeast of Building13 at the West Burn Pads Landfill, and in the east and southeast areas of the Bum Cage AshDisposal Landfill, with residual explosives contamination in the ditches of Pads I-Wand 2-W. Explosives detected in soil sampling. Highest detections were HMX at 27,000 llg/gand RDX at J40 llg/g in surface samples.

0 Metals contamination fairly widespread throughout area. Arsenic, barium, chromium, andlead were detected in all soils tested from the site. Other metals, such as mercury, silver andcadmium were also found. The depth of explosives, metals, and other contamination appearsto be limited to three or four feet depth.

0 Low levels of SVOCs and VOCs detected.

North Bum Pads 0 Extensive metals contamination of surficial soils. Metals decreased with soil depth, buteven at three feet, there were high levels of antimony (122.0 ~g/g). barium (648.0 ~g/g),

cadmium (1.49 ~g/g), chromium (74.2 ~g/g), copper (11,500 ~g/g), lead (5,930.0 ~g/g),

nickel (278.0 ~g/g). silver (1.66 ~g/g), sodium (356.0 ~g/g), and zinc (8.040.0 ~g/g).

Fire Training Pit • Metals contarninaion, highest (greater than) ,000 llg/g) at center of pit. Contaminationreaches to depth of two feet.

0 SVOCs highest (60 ~g/g) in surface samples but also found at 15 fi depth (12 ~g/g).

0 Highest detections (200 ~g/g) of VOCs found at 12 fi depth.


March 21, 1998Page 6~5

Table 6-4. Soil Contamination at Spring Creek Watershed Facilities


PCB Roundhouse . Low levels (generally less than 2 ~g/g) PCBs detected in surface soils over much of yardTransformer and in some samples to west and south of yard.Storage Area

Available data at the Contaminated Waste Processor, Explosive Waste Incinerator and Ammunition Box

Chipper Disposal Area Pit and North Burn Pads Landfill did not indicate significant contamination.

6.1.6.2 Surface Water and Sediments. Previous investigation showed RDX and several other

explosives in surface water and sediment samples collected downgradient of the Explosives Disposal Area

and West Burn Pads. In Spring 1997 investigations, a total of six sediment and four surface water samples

were analyzed from four sampling areas (7A through 70 and are shown in Exhibit 4-2) in the Spring Creek

Drainage (Harza 1997a). No explosives were detected in either surface water or sediment at location 7A,

the upstreammost location draining the northeast corner of the lAAAP, including parts of the Explosive

Disposal Area. Trace concentrations of explosives were detected in surface water at locations 7B and 7C,

totalling 0.72 and 0.51 1lg!L, respectively. Although this suggests a possible continuing source of

contamination, no explosives were detected in the sediment samples at these locations, suggesting that

sediments and do not represent a source of residual contamination. No explosives were detected in samples

from 70, located about II, mile outside the IAAAP boundary downstream. Based on these results, one or

more trace sources ofexplosives contamination may be presently reaching the intermediate reaches of Spring

Creek, within the lAAAP boundaries. However, concentrations are small and no off-site contamination was

identified. Metals concentrations in the water were below Iowa chronic water quality standards for limited

resource waters. Metals in sediment were all found to be below the EPA's Ecotox thresholds. (Tables 6-5

and 6-6).

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft FinaIJ


Table 6-5. Results of Surface Water Sampling along Spring Creek

Sampling Locations VOCs (ltg/L) SVOCs (ltg/L) Explosives (ltglL) Metals > WQS

7A.just east of Yard C Methylene chloride (10.IB) None None None

7B-east of Yard D Methylene chloride (12.1B) None RDX (O.72J) None

7C-near the southeast Methylene chloride (8.3B) None RDX (0.51J) Noneproperty boundary

7D-one mile southeast of None None None Noneproperty boundary

B - Detected In blank as well as sample.Source: Harza 1997a

J - Estimated value below the quanlltallOn limit.

Table 6-6. Results of Sediment Sampling along Spring Creek

Sampling VOCs SVOCs Explosives Metals ExceedingLocations (ltg/kg) (ltg/kg) (ltg/kg) Ecotox Criteria

7AI (1 1\) Methylene chloride Butylbenzlphthalate None None(18.8B) (293J)

7BI (I 1\) Methylene chloride (8.7B) None None None

7BI (31\) None None None None

7CI (1 1\) Methylene chloride (4.7B) None None None

7CI (I 1\) None None None None

7DI (3 1\) Methylene chloride (7.6B) None None NoneB - Detected In blank as well as sample.Source: Harza 1997a

J - Estimated value below the quantltatlOn limit.

6.1.6.3 Groundwater. Groundwater contamination, represented by total explosives concentrations, has

been described as relatively widespread throughout IAAAP. Table 6-7 summarizes detections of chemical

parameter groups in samples from the noted various facilities drained by Spring Creek.

Table 6-7. Contaminants Detected in Groundwater

Location Metals Explosives VOCs SVOCs

Explosive Disposal Area (EDA) x x x x

Contaminated Waste Processor (CWP)

Explosive Waste Incinerator (EWI) No samples collected.

Ammunition Box Chipper Disposal Pit x

West Bum Pads x x x



Table 6-7. Contaminants Detected in Groundwater


North Bum Pads x x

Fire Training Pit x x x

PCB Roundhouse Transfonner Storage Area No samples collected.

North Bum Pads Landfill x I x x I

The following paragraphs highlight key contaminants from each contaminant grouping for each facility

marked in Table 6-7. Concentrations indicate the highest level reported of the particular contaminant in all

wells in the vicinity of the facility. All data are from the RI (JAYCOR 1996).

At the EDA, explosives concentrations in groundwater were as high as 52.9 IlgIL for RDX and 51.2 IlgIL

for HMX. At the West Burn Pads, reported values for RDX and HMX were 61.4 and 15.5 IlgfL,

respectively. May 1995 data for RDX at the West Burn Pads was significantly lower than a 2200 Ilg/L level

reported in May 1993. Low levels ofexplosives were reported at the North Bum Pads, including RDX (2.0

IlgIL) and 2,4,6-TNT (1.51 IlgIL) and the North Bum Pads Landfill, including HMX (11.2 Ilg/L) and RDX

(5.26 IlgIL).

The maximum reported metal concentrations at the EDA were: arsenic (24.3 Ilg/L), chromium (565 Ilg/L),

lead (230 IlgIL), mercury (0.467 IlgIL) and vanadium 848 (llgIL). Chromium (83.6 IlgIL), arsenic (6.8 Ilg/L),

lead (17.7 Ilg/L) and vanadium (135 Ilg/L) were reported at the Ammunition Box Chipper Disposal Pit.

Lead (48.9 IlgIL), chromium (116 IlgIL), and arsenic (6.61 IlgIL) were reported at the West Burn Pads. The

maximum metals concentrations reported at the North Bum Pads were: arsenic (14.2 Ilg/L), chromium (35.8

IlgIL), lead (19.5 IlgIL), and vanadium (59.4 IlgfL). Low levels of metals were found in the Fire Training

Pit, including arsenic (4.26 Ilg/L), chromium (l4.9Ilg/L) and lead (23.3 Ilg/L). Low levels of metals were

reported at the North Burn Pads Landfill, including arsenic (2.8 IlgIL), chromium (13.2 IlgIL), and lead (3.2

Ilg/L).

Two wells of the eleven at the EDA reported detectable levels ofVOCs, the highest concentration being

toluene at 6.3 IlgIL. Detectable levels ofVOCs at the West Bum Pads included TCE (73.0 Ilg/L), 1,2-DCE

(28.0 IlgfL) and carbon disulfide (20.0 IlgfL). At the Fire Training Area, reported high levels of VOCs

included toluene (20,000 IlgfL), methyl n-butyl ketone (20,000 IlgIL), acetone (100,000 IlgfL), 1,2

dichoroethene (20,000 IlgIL), I,I-dichloroethane (5,000 IlgIL), 1,1, I-trichloroethane (20,000 IlgIL), as well



as other

Iowa Army Ammunition PlantEcological Risk Assessment Addendum fDrsft Final)


petroleum-related VOCs. One well at the North Bum Pads Landfill was reported to contain carbon disulfide

(18.0 flgIL).

One well at the EDA reported detectable levels of the SVOC 4-cresol (24.0 flgIL). Elevated SVOCs at the

Fire Training Pit included phenol (6,000 flgIL), naphthalene (90 flgIL), and 2-methylnaphthalene (100 flgIL).

6.1.6.4 NPDES Discharges. None of the IAAAP's NPDES-permitted outfalls discharge to Spring

Creek. The City of West Burlington's WWTP discharges to Spring Creek upstream of the property.




1997b). Benthic sampling stations along Spring Creek yielded 137 to 294 individuals and 8 to 17

macroinvertebrate taxa at each site. Number collected by station and the HBI tolerance values for all taxa

are presented in Appendix F. Pollution tolerance values, as used in the RBP, are provided by Hilsenhoff

(1988). The greatest number of taxa were collected at reference station BC9 (13 taxa) and offsite station

BC8 (17 taxa) downstream ofIAAAP. Taxa that accounted for most of the benthos were:

chironomid midge larvae 26%

blood-red chironomid midge larvae 15%

hydropsychid caddis fly nymphs 18%

freshwater clams 10%

asellid isopods 9%

These taxa are fairly tolerant of pollution. HBI tolerance values vary from 0 (intolerant, sensitive) to 10

(highly tolerant). Hydrophychids have a tolerance value of 4; chironomids 6; blood-red chironomids and

aseJlids, 8. There are no pollution tolerance values for clams.


March 21, 1998Page 6-10

6.2.2 Fish

The fantail darter and the Johnny darter were collected in Spring Creek. Fantail darters were caught at two

sampling Stations (SC2 and SC6). Johnny darters were caught at two Stations (SCI and SC4) and both

species of darters were collected at Station SC6. Whole fish were analyzed for explosives and

biomagnifying COECs. Results indicate that aquatic biota are not accumulating explosives in Spring Creek.

All analyses of explosives in fish tissue were non-detects. with the corresponding MDLs indicated by the

"<" symbol (Table 6-8).

Table 6-8. Explosives Contamination in Fisb in SI rin2 Creek

Station SCI SC2 SC2 SC4 SC5 SC6 SC6Field 10 SCI-F SC2-F SC2-F-DUP SC4-F SC5-F SC6-F SC6-F-DUPLab 10 5000-15 5000-19 5000-17 5000·20 5001-02 5000·16 5000-13

Soecies Johnnv Fantail Fantail Johnnv Mixed Fantail Fantail

Analvle I ,./k. wei wei htl1,3,5-Trinitrobenzene <312 <312 <312 <312 <312 <312 <312

] ,3-Dinitrobenzene <295 <295 <295 <295 <295 <295 <2952,4,6·Trinitrotoluene <314 <314 <314 <314 <314 <314 <314

2,4-Dinitrotoluene <316 <316 <316 <316 <316 <316 <316

2.6-Dinitrotoluene <288 <288 <288 <288 <288 <288 <288

2-Arnino-4,6-Dinitrotoluene <263 <263 <263 <263 <263 <263 <2632-Nitrotoluene <291 <291 <291 <291 <291 <291 <291

3-Nitrotoluene <342 <342 <342 <342 <342 <342 <342

4-Amino-2,6·Dinitrotoluene <283 <283 <283 <283 <283 <283 <283

4-Nitrotoluene <269 <269 <269 <269 <269 <269 <269

RDX <273 <273 <273 <273 <273 <273 <273

Nitrobenzene <329 <329 <329 <329 <329 <329 <329

HMX <285 <285 <285 <285 <285 <285 <285

Tetrvl <286 <286 <286 <286 <286 <286 <286

Analysis of mercury in darters from Spring creek also indicated no significant uptake (Table 6-9). Levels

of mercury in darters did not exceed 0.13 mg/kg. For comparative purposes, the FDA limit of mercury in

fish for human consumption is one mg/kg.


March 21. 1998Page 6·11

Table 6-9. Metal Contamination in Fisb in Sprine Creek

Station SCI SC2 SC2 SC4 SC5 SC6 SC6Field lD SCI-F SC2-F SC2-F-DUP SC4-F SC5-F SC6-F-DUP SC6-FLablD 5000-15 5000-19 5000-17 5000-20 5001-02 5000-13 5000-16Species Johnny Fantail Fantail Johnnv Mixed Fantail FantailAnalvte (me/ke wet weiehtl

Mercury 0.12 I <0.10 <0.10 <0.10 I <0.10 I <0.10 I 0.13

No pesticides in Spring Creek fish tissue were above the MDLs, except for dieldrin and heptachlor epoxide.

The isolated presence ofdieldrin and heptachlor epoxide point to an agricultural source of the pesticide. No

uptake of COEC pesticides/PCBs in Spring Creek is evidenced based on analytical results (Table 6- I0).

Table 6-10. Pesticide Contamination in Fisb in Sprin!! Creek

Station SCI SC2 SC2 SC4 SC5 SC6 SC6Field lD SCI-F SC2-F SC2-F-DUP SC4-F SC5-F SC6-F SC6-F-DUPLab lD 5000-15 5000-19 5000-17 5000-20 5001-02 5000-16 5000-13Species Johnny Fantail Fantail Johnnv Mixed Fantail Fantail

Analyte ("elke)alpha-BHC <1.6 <1.6 <1.6 <1.6 <1.6 <1.6 <1.6beta-BHC <1.5 <1.5 <1.5 <1.5 <1.5 <1.5 <1.5

delta·BHC <1.6 <1.6 <1.6 <1.6 <1.6 <1.6 <1.6

gamma-BHC <1.6 <1.6 <1.6 <1.6 <1.6 <1.6 <1.6

Heotachlor <1.6 <1.6 <1.6 <1.6 <1.6 <1.6 <1.6

Aldrio <1.6 <1.6 <1.6 <1.6 <1.6 <1.6 <1.6

Heotachlor eooxide <1.7 <1.7 <1.7 <1.7 <1.7 <1.7 3.4Endosulfan I <1.7 <1.7 <1.7 <1.7 <1.7 <1.7 <1.7

Dieldrin 12.0 36.0 33.0 23.0 5.5 20.0 21.04.4'-DDE <1.7 <1.7 <1.7 <1.7 <1.7 <1.7 <1.7

Endrin <1.6 <1.6 <1.6 <1.6 <1.6 <1.6 <1.6

Endosulfan II <1.6 <1.6 <1.6 <1.6 <1.6 <1.6 <1.6

4.4'·DDD <1.7 <1.7 <1.7 <1.7 <1.7 <1.7 <1.7

Endosulfan sulfate <1.6 <1.6 <1.6 <1.6 <1.6 <1.6 <1.6

4,4'-DDT <1.6 <1.6 <1.6 <1.6 <1.6 <1.6 <1.6

Methoxvchlor <1.7 <1.7 <1.7 <1.7 <1.7 <1.7 <1.7

Endrin aldehvde <1.7 <1.7 <1.7 <1.7 <1.7 <1.7 <1.7

Chlordane <3.3 <3.3 <3.3 <3.3 <3.3 <3.3 <3.3

Toxaohene <33.0 <33.0 <33.0 <33.0 <33.0 <33.0 <33.0

Arochlor 1016 <16.7 <16.7 <16.7 <16.7 <16.7 <16.7 <16.7

Arochlor 1221 <27.2 <27.2 <27.2 <27.2 <27.2 <27.2 <27.2

Arochlor 1232 <15.8 <15.8 <15.8 <15.8 <15.8 <15.8 <15.8

Arochlor 1242 <16.7 <16.7 <16.7 <16.7 <16.7 <16.7 <16.7

Arochlor 1248 <16.5 <16.5 <16.5 <16.5 <16.5 <16.5 <16.5


March 21, 1998Page 6-12

Table 6-10. Pesticide Contamination in Fish in Snrin!! Creek

Station SCI SC2 SC2 SC4 SC5 SC6 SC6Field ID SCI-F SC2-F SC2-F-DUP SC4-F SC5-F SC6-F SC6-F-DUPLab ID 5000-15 5000-19 5000-17 5000-20 5001-02 5000-16 5000-13Soecies Johnnv Fantail Fantail Johnnv Mixed Fantail Fantail

Analvte (1l~/k~)

Arochlor 1254 <16.2 <16.2 <16.2 <16.2 <16.2 <16.2 <16.2Arochlor 1260 <16.4 <16.4 <16.4 <16.4 <16.4 <16.4 <16.4Endrin ketone <1.7 <1.7 <1.7 <1.7 <1.7 <1.7 <1.7

6.2.3 Small Mammals

Mammal tissues obtained at lbree oflbe four sampling locations in the Spring Creek watershed were utilized

to assess the risk to viability ofwildlife populations (Table 6-11). White-footed mice (Peromyscus leucopus)

were the most common rodent caught at these trapping locations. However, because there was insufficient

mouse tissue for all analyses, meadow voles (Micro(us pennsylvanicus) and short-tailed shrews (Blarina

brevicauda) were also analyzed. Weights shown in the table below are field weights of wet animals.

Table 6-11. Small Mammals from Spring Creek Watershed Analyzed for Selected COECs

Site Date Species Weight (g) Lab Id. Analytical Parameters

SCI 7/18/97 Peromvscus leucoDus 45 1153 He. Pb, Th. Ae. Fe, AI, Cr, EXDlosives, PestIPCBs

SC2 7/21/97 Micro/us vennsvlvanicus 42 1154 He, Pb, Th, Ae, AI, Fe, Cr, EXDlosives, PestIPCBs

SC4 7/22/97 Blarina brevicauda 28 1151 He, Pb, Th, Ae, AI, Fe, Cr. EXDlosives

SC4 7/17/97 Peromvscus leuconus 65 1152 He, Pb. Th, Ae. Cr, AI, Fe, EXDlosives. Pest/PCBs

Minor accumulations ofRDX, nitrobenzene, and chromium were found in mammal tissue (Tables 6-12

through 6-14). Mammals captured at SCI, the reference site, showed the highest concentration ofRDX in

their tissues. Aerial deposition of RDX from other sites in the watershed may be the source of this chemical

contaminating the reference site.

Table 6-12. Explosives Contamination in Mammals/Snrin~ Creek Watershed

Station SCI SC2 SC4 SC4

Field ID 1t53 1t54 It52 1151

LablD 5002-14 5002-15 5002-13 5002-12

Soecies Mouse Vole Mouse Shrew

AnaMe (1l~/k~ wet wei!!htlJ 3 5~Trinitrobenzene <312 <312 I <312 <312

lows Army Ammunition PlantEcological Risk Assessment Addendum fOraft Final)

March 21, 1998Page 6-13

Table 6-12. Explosives Contamination in Mammals/Sprine Creek Watershed

Station SCI SC2 SC4 SC4Field ID 1153 1154 1152 1151Lab ID 5002-14 5002-15 5002-13 5002-12Species Mouse Vole Mouse Shrew

Analvte Ia./k. wet wei.htlJ.3-Dinitrobenzene <295 <295 <295 <2952,4,6-Trinitrotoluene <314 <314 <314 <314

2,4-Dinitrotoluene <316 <316 <316 <3162,6-Dinitrotoluene <288 <288 <288 <288

2-Amino-4,6-Dinitrotoluene <263 <263 <263 <263

2-Nitrotoluene <291 <291 <291 <291

3-Nitrotoluene <342 <342 <342 <342

4-Arnino-2,6-Dinitrotoluene <283 <283 <283 <283

4-Nitrotoluene <269 <269 <269 <269

RDX 4000 550 <273 1300

Nitrobenzene <329 6800 <329 <329

HMX <285 <285 <285 <285

Tetrvl <286 <286 <286 <286

Aluminum and iron were detectable in all mammals. Chromium was the only other metal detected, and it

was found in tissue from a vole captured at SC2. These levels ofmetals in lAAAP wild rodents are generally

consistent with other studies of small mammals inhabiting unpolluted areas (Sawicka-Kapusta ef al. 1987,

Wlostowski ef al. 1988).

Table 6-13. Metal Contamination in Mammals/Sarine Creek Watershed


Field ID 1153 1154 1152 1151

Lab ID 5002·14 5002-15 5002-13 5002-12

Saecies Mouse Vole Mouse Shrew

Analvte me/ke)

Aluminum 29.6 5.1 19.4 48.2

Chromium <0.50 0.69 <0.50 <0.50

Iron 143 82.2 122 226

Lead <2.5 <2.5 <2.5 <2.5

Mercurv <0.10 <0.10 <0.10 <0.10

Silver <0.50 <0.50 <0.50 <0.50

Thallium <3.0 <3.0 <3.0 <3.0

No pesticides were detected in mammal tissue at Spring Creek (Table 6-14).


Ma,ch21,1998Page 6-14

Table 6-14. Pesticide Contamination in Mammals/Snrin" Creek Watershed

Station SCI SC2 SC4

Field ID 1153 1154 1152

Lab ID 5002-14 5002-15 5002-\3

Soecies Mouse Vole MouseAnalvte h,,,/k.'

aloha-BHC <1.6 <1.6 <1.6

beta-BHC <1.5 <1.5 <1.5

delta-BHC <1.6 <1.6 <1.6

~amma-BHC <1.6 <1.6 <1.6

Heotachlor <1.6 <1.6 <1.6

Aldrin <1.6 <1.6 <1.6

Heotachlor eooxide <1.7 <1.7 <1.7

Endosulfan I <1.7 <1.7 <1.7

Dieldrin <1.6 <1.6 <1.6

4,4'-DDE <1.7 <1.7 <1.7

Endrin <1.6 <1.6 <1.6

Endosulfan II <1.6 <1.6 <1.6

4,4'-DDD <1.7 <1.7 <1.7

Endosulfan sulfate <1.6 <1.6 <1.6

4,4'-DDT <1.6 <1.6 <1.6

Methoxychlor <1.7 <1.7 <1.7

Endrin aldehyde <1.7 <1.7 <1.7

Chlordane <3.3 <3.3 <3.3

Toxaohene <33.0 <33.0 <33.0

Arochlor 1016 <16.7 <16.7 <16.7

Arochlor 1221 <27.2 <27.2 <27.2

Arachlar 1232 <15.8 <15.8 <15.8

Arachlar 1242 <16.7 <16.7 <16.7

Arachlar 1248 <16.5 <16.5 <16.5

Arochlor 1254 <16.2 <16.2 <16.2

Arochlor 1260 <16.4 <16.4 <16.4

Endrin ketone <1.7 <1.7 <1.7

6.2.4 Soils

Surface soil samples were collected from the three sites where small mammals were captured for tissue

analysis. The background sample (SCI) showed no measurable explosives, pesticides or PCBs. No

explosives were reported above the MDLs for the other two sampling sites. In soils from both sites, minor

concentrations of chromium, lead, silver, and thallium were reported, and at one site (SC4), a minor

concentration of Arochlor 1260 was detected. Results are summarized in Tables 6-15 through 6-17.


March 21, 1998Page 6-15

Table 6-15. Explosives Contamination in SoilslSprin Creek Watershed

Station SCI SCZ SC2 SC4Field ID SCI-S SCZ-S SC2-S-DUP SC4-SLabID 5000-01 5000-05 5000-11 5000-09

Analvte I"e/kel1,3,5-Trinitrobenzene <312 <312 <312 <312

1,3-Dinitrobenzene <295 <295 <295 <295

2,4,6-Trinitrotoluene <314 <314 <314 <314

2,4-Dinitrotoluene <316 <316 <316 <3162,6-Dinitrotoluene <288 <288 <288 <288

2·Amino-4,6·Dinitrotoluene <263 <263 <263 <263

2-Nitrotoluene <291 <291 <291 <291

3-Nitrotoluene <342 <342 <342 <342

4-Amino-2,6-Dinitrotoluene <283 <283 <283 <283

4-Nitrotoluene <269 <269 <269 <269

RDX <273 <273 <273 <273

Nitrobenzene <329 <329 <329 <329

HMX <285 <285 <285 <285

Tetryl <286 <286 <286 <286

Table 6-16. Metal Contamination in Soils/S rin2 Creek Watershed

Station SCI SC2 2 SC4

Field ID SCI-S SC2-S SC2-S-DUP SC4-S

Lab ID 5000-01 5000-05 5000-11 5000-09

Analvte (m Ike)

Chromium 8.6 10.0 9.8 7.6

Lead 14.1 J6.6 16.0 10.7

Mercurv <0.12 <0.13 <0.13 <0.12

Silver <0.58 0.33 I <0.62

Thallium 3.5 <3.8 <3.8 <3.7

Table 6-17. Pesticide Contamination in Soils/Sprin2 Creek Watershed


Field ID SCI-S SC2-S SC2-S-DUP SC4-S

Lab ID 5000-0J 5000-05 5000-11 5000-09

Analvte h"uk.lalpha-BHC <0.63 <0.7 <0.69 <0.68

beta-BHC <0.59 <0.66 <0.65 <0.64

delta-BHC <0.63 <0.69 <0.69 <0.67

.amma-BHC <0.6 <0.66 <0.66 <0.65

Hemachlor <0.63 <0.7 <0.7 <0.68

Aldrin <0.61 <0.68 <0.67 <0.66

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft FinalJ

March 21, 1998P8ge6-16

Table 6-17. Pesticide Contamination in Soils/Snrin!! Creek Watershed


Field ID SCI-S SC2-S SC2-8-DUP SC4-S

LabID 5000-01 5000-05 5000-11 5000-09

A.alvte (""/k.l

HeDtachlor eDoxide <0.64 <0.71 <0.71 <0.69

Endosulfao I <0.64 <0.71 <0.7 <0.69

Dieldrin <0.62 <0.68 <0.68 <0.67

4,4'-DDE <0.64 <0.71 <0.7 <0.69

Endrin <0.62 <0.69 <0.69 <0.67

Endosulfao II <0.63 <0.7 <0.69 <0.68

4,4'-DDD <0.64 <0.71 <0.7 <0.69

Endosulfao sulfate <0.62 <0.68 <0.68 <0.66

4,4'-DDT <0.6 <0.66 <0.66 <0.64

Methoxychlor <0.64 <0.7 <0.7 <0.69

Endrin aldehyde <0.65 <0.71 <0.71 <0.7

Chlordane <1.3 <1.4 <1.4 <1.4

Toxaohene <12.7 <14.0 <14.0 <13.7

Arochlor 1016 <6.4 <7.1 <7.1 <6.9

Arochlor 1221 <10.5 <11.6 <11.5 <11.3

Arochlor 1232 <6.1 <6.7 <6.7 <6.9

Arochlor 1242 <6.4 <7.1 <7.1 <6.8

Arochlor 1248 <6.3 <7 <7 <6.7

Arochlor 1254 <6.2 <6.9 <6.9 <6.8

Arochlor 1260 <6.3 <7 <7 49.0

Endrin ketone <0.64 <0.71 <0.71 <0.69

6.2.5 Water

Available information on contaminants in surface water was limited to total pollutant concentrations.

Surface water was sampled on October 27, 1997 to speciate metals into dissolved and filtrable fractions.

Samples were taken at the reference station and at the most downstream station on the 1AAAP (Table 6-18).

While aluminum and iron are largely present in particulate forms, barium and zinc are present largely in

dissolved form. None of the measurements ofmetals shown in Table 6-18 exceed the Iowa chronic or acute

water quality standards for limited resource waters.


March 21, 1998Page 6-17

Table 6-18. Speciation of Metals in Surface Water - Spring Creek Watershed (mgIL)

SCI (reference) SC4 (IAAAP south boundary)


Aluminum <0.05 0.67 0.15 1.7

Barium 0.076 0.084 0.14 0.11

Cobalt <0.005 <0.005 <0.005 <0.005

Copper <0.010 <0.010 0.0135 <0.010

Iron 0.085 LI 0.19 2.4

Lead <0.025 <0.025 <0.025 <0.025

Manganese 0.057 0.086 0.064 0.15

Silver <0.005 <0.005 <0.005 <0.005

Thallium <0.03 <0.03 <0.03 <0.03

Vanadium <0.005 0.0051 <0.005 <0.005

Zinc 0.0056 0.011 0.055 0.018


The ecological risk within the Spring Creek watershed is assessed separately for aquatic ecosytems and




Aquatic assessment endpoints are the individual survival and viability of the state-listed threatened

orangethroat darter and the health ofthe benthic macroinvertebrate community. To assess the risk to the

orangethroat darter population, the levels of COECs bioaccumulated in individuals offantail and Johnny

darters were measured or estimated from models. The significance of these levels were evaluated using

RTVs from the literature for evaluation of effects. As the selected RTVs are, in general, derived from

multiple species testing, the conclusions are relevant not only to orangethroat darters, but to the fish


March 21, 1998Page 6-18

community at large. The health of the aquatic benthic community was measured using the Rapid

Bioassessment Protocol III developed by the USEPA (Plafkin, et al. 1989).

6.3.1.1 Chemicals of Ecological Concern. The maximum and 95% UCL total concentrations of the

preliminary aquatic COECs for the Spring Creek watershed are shown in Table 6-19, derived as discussed

in Section 3.6. Three explosives, ten metals and one PNA are aquatic COECs. None ofthe COECs are listed

by the USEPA as biomagnifiers.

Table 6-19. Aquatic COECs for the Spring Creek Watershed

Contaminant Maximum Concentration (112/L) 95% VCL ("./L)

1,3,5-trinitrobenzene 4.8 (8) 4.8 (8)

HMX 55 (8) 55 (8)190 (W) 16.5 (W)

RDX 3.1 (8) 3.1 (8)470 (W) 90.3 (W)

Aluminum 13,000 (8) 13,000 (8)9,710 (W) 2,504 (W)

Barium 1,960 (8) 1,960 (8)4,240 (W) 312 (W)

Beryllium 1.7 (8) I.7 (8)

Cobalt 33.7 (8) 33.7 (8)

Copper 80.7 (W) 13.2 (W)

Iron 25,800 (8) 25,800 (8)8,190 (W) 2,465 (W)

Lead 20.7 (W) 9.26 (W)

Manganese 2,250 (8) 2,250 (8)195 (W) 104.2 (W)

Selenium 1.8 (8) 1.8 (8)

Vanadium 46.3 (8) 46.3 (8)589 (W) 30.3 (W)

Benzo[det]phenanthrene 0.45 (8) 0.45 (8)W Water S Sediment

6,3.1.2 Exposure Assessment. Aquatic concentrations ofCOEC for exposure estimates were initially

taken as the 95% UCL of all surface water measurements in the Spring Creek watershed. This estimates the

central tendency of the COEC concentration as well as accounting for uncertainties in the accuracy of the

measurements. In estimating the 95% UCL, nondetected concentrations were taken as 50% of the MDL.

Exposure concentrations represent total metals in surface water, as that was the basis of JAYCOR's


March 2/, /998Page 6-/9

measurements. Use of exposure point concentrations calculated from total metal concentrations results in

considerable overprediction ofexposures, as only a fraction of total metals are bioavailable. Dissolved metal

concentrations are a mOre appropriate measure of bioavailability. Laboratory toxicity tests are conducted

under conditions favoring toxicant bioavailability; lab dilution waters contain low concentrations of

suspended solids and organic carbon. Standard test methods require high purity dilution water. Recognizing

this, dissolved COEC concentrations are to be used in aquatic ecological risk assessments (WERF 1996).


operational definition for the dissolved fraction (see Table 6-18). Eleven metals were speciated in this

manner. This allowed estimation of exposure concentrations as dissolved metals for eleven elements. In

other cases, total pollutant concentrations were used.

6.3.1.3 Risk Estimates. Aquatic RTVs were taken from a variety of sources and were presented in

Chapter 4. Hazard quotients computed as the exposure point concentration (95%UCL) in Spring Creek

divided by the aquatic RTV are tabulated in Table 6-20 for each aquatic COEC.

Table 6-20. Aquatic Hazard Quotients for Spring Creek Watershed


1,3.5-Trinitrobenzene 0.299 120 0.002

HMX 16.5 3300 0.005

RDX 90.3 4900 0.02

Aluminum 150 3288 0.05

Iron 190 1300 0.1

Lead 25 18.9 1.3

Barium 110 4 27

Bervllium 2.5 57 0.04

Conner 13.19 3.8 3.5

Selenium 1.68 88.3 0.02

Cobalt 5 23 0.2

ManQanese 64 120 0.5

Vanadium 5 20 0.3

Benzo'det1nhenanthrene 1.4 2000 0.0007

Based upon total metal concentrations, HQ greater than or equal to unity would be expected to present


March 21, 1998Page 6-20

significant risk; this is notably apparent for copper, lead, and barium. Recall that background concentrations

of metals were not part of the data screening algorithm shown in Exhibit 3-2. JAYCOR (1996) defined

background concentrations for total concentrations of these three metals. Table 6-21 compares these

background levels to 95% UCL concentrations of total (particulate plus dissolved) metals.

Table 6-21. Comparison of Background and 95%UCL Concentrations

(pgIL) of Total Metals in Spring Creek

Metal Background 95%UCL

Lead I to 5 9.3

Copper 8 13.2

Barium III to 227 312

For each of these three metals, the 95%UCL concentrations of total metal (dissolved plus particulate) are

slightly above JAYCOR's definition of background. Copper HQ is 3.5 and lead HQ is 1.3. The RTV was

estimated using regression techniques based upon acute testing and have considerable uncertainty associated

with them (Suter and Tsao 1996).

Barium HQ values are greater than one, indicating a possibility of adverse effects. This value is based on

dissolved barium concentration in surface water, as measured on October 27,1997. The barium RTV is a

Tier 11 SCV, and is based upon a single chronic toxicity test ofDaphnia magna, a microcrustecean not a fish

(Suter and Tsao 1996). In that test, the researchers estimated an ECI6 of 5,800 flg/L, and applied the Tier

11 procedures to this results to recommend a SCV of4 flg/L as a RTV to protect all Great Lakes aquatic life.

No biomagnifying COECs were identified for this watershed. Field measurements in darter tissue confirmed

this. Mercury in darter tissue was below MDLs at all stations except SC I, the reference site, and SC6, an

offsite station. Johnny darter at SCI had whole body Hg residues of 0.12 mglkg and fantail darter from SC6

had whole body residues of 0.13. These mercury levels are well below the proposed RTV ofa no-observed

adverse-effect mercury residue of 2.5 mg/kg wet weight. Dieldrin was detected in all darter samples from

the

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Drsft Final)

March 21, 1998Page 6·21

watershed, and heptachlor epoxide was detected in darters from SC6. These pesticides are not COECs and

their presence in fish tissue can be attributed to the agricultural activities in the watershed.

6.3.1.4 Aquatic Macroinvertebrate Community Structure. Six benthos sampling sites were spaced

throughout Spring Creek, extending well downstream of the IAAAP. Table 6-22 provides the metric scores

computed using the Rapid Bioassessment Protocol III, as described in Section 3.8.

Table 6-22. Rapid Bioassessment Protocol III for Spring Creek

Station No. SCI SC2 SC3 SC4 SC5 SC6M t ~ Species Richness II 15 13 10 II I

Biological Condition 6 6 6 6 6 6M2 • HBI (modified) 7.5 5.8 6.0 5.8 5.8 5.2

Biological Condition 6 6 6 6 6 6M3 -ScrapersIFilterers 267% 27% 80% 0% 23% 23%

Biological Condition 6 0 2 0 0 0M4 - EPT/Chironomidae 567% 463% 61% 23% 70% 85%

Biological Condition 6 6 0 0 0 0M5 . % Dominant Taxon 61% 41% 25% 55% 34% 28%

Biological Condition 0 0 4 0 2 4

M6 • EPT Index 3 4 4 3 3 5Biological Condition 6 6 6 6 6 6

M7 . Community Loss 0.00 0.20 0.15 0.40 0.27 0.11Biological Condition 6 6 6 6 6 6

M8 -Shreddersffotal 7% 14% 4% 11% 3% 0%

Biological Condition 6 6 6 6 4 0% Comparison to Ref. Score 100% 86% 86% 71% 71% 67%

Biological ConditionReference Unimpaired Unimpaired

Slightly Slightly SlightlyCategory impaired impaired impaired

Site SCI, is upstream of all IAAAP activities and is considered the watershed reference site. Sites SC2 and

SC3, within the IAAAP, are rated as unimpaired in comparison to the reference. Farther downstream,

Stations SC4, 5 and 6, were rated as slightly impaired. Macroinvertebrate communities at these three lower

stations differed from other stations largely on the basis of an abundance of chironomids, which, in turn,

lowered the scraper/filterer, EPT/chironomid and shredders/total ratios. These differences indicated

communities that were based more on fine particulate organic matter in the water column (a condition that

is generally indicative of organic pollution) than on leaves and other coarse particulate organic matter. Even

the stations that were rated as slightly impaired scored better than the reference station on some metrics.

However, Biological Condition Scores allow no credit for exceeding the metric scores for the reference

station. Because most of the watershed is intensively cultivated, one might argue that the reference station


March 21. 1998Page 6-22

itself represents a slightly impaired condition. Nonetheless, the impairment exhibited at those stations having

Biological Condition Scores suggesting a slightly degraded condition is considered to be more the result of

agricultural practices at the site than caused by IAAAP operations.

6.3.1.5 Uncertainty. Significant uncertainty is attributed to the exposure estimates in Table 6-20.

• No biomagnifying aquatic COECs were identified during the prescreening process. The uncertainty

of this finding is low, as it is supported by independent field measurements. Biomagnifiers, as well

as explosive chemicals, were generally below MDLs in darters.

• Uncertainty of the RBP is considered to be low and an accurate appraisal of ecosystem stress. The

technique is widely used for evaluation of aquatic impacts and is considered a reliable tool by

regulatory agencies in nearly all states. Iowa DNR routinely includes stream bioassessments in new

NPDES permit as a monitoring requirement. The RBP includes eight metrics, and impacts not

assessed by one metric should be evaluated up by another. Hence, the benthic community

assessment should provide the greatest level of accuracy with the least uncertainty.

• The risk estimate for aquatic metals has a high uncertainty. The RTV for lead and copper were

estimated using regression techniques based upon acute testing and have considerable uncertainty

associated with them (Suter and Tsao 1996). The barium is a Tier II SCV, and is based upon a single

chronic toxicity test of Daphnia magna, a microcrustecean not a fish (Suter and Tsao 1996). In that

test, the researchers estimated an ECI6 of 5,800 ~g/L, and applied the Tier II procedures to this

results to recommend a SCV of 4 ~glL as a RTV to protect all Great Lakes aquatic life.

6.3.1.6 Summary of Aquatic Risks. Aquatic ecosystem health, as measured by the RBP appraisal of

benthic community structure, is unaffected by IAAAP operations. Agricultural activities in areas

downstream ofIAAAP open the stream to sunlight and cause a shift in the community from one feeding on

leaves and other coarse particulate organic matter to one feeding on fine particulate organic matter in the

water column. Generally this is considered indicative of organic pollution.

Additional evidence that agriculture is affecting the aquatic ecosystem more so than munitions manufacturing

is found in the assessment of contaminant biomagnification. No biomagnifying COECs were identified in

the prescreening process (Table 6-19) and this was confirmed through field measurements. Mercury in darter

10 WB Army Ammunition PlantEcological Risk Assessment Addendum (Draft Final)

March 21. 1998Page 6·23

tissue was below MDLs at all stations except SCI, the reference station, and SC6, the most downstream

station and well outside the lAAAP boundary. Johnny darters at these two stations had whole body mercury

residues well below the proposed RTV. Dieldrin was detected in all darter samples from the watershed, and

heptachlor epoxide was detected in darters from SC6. These pesticides are not COECs and their presence

in fish tissue is most likely due to the agricultural activities in the watershed.

Based upon total metal concentrations, some risk to the threatened species orangethroat darter would be

expected from exposure to barium, copper, and lead. Our evaluation of risks from these metals has a high

degree of uncertainty associated with it, as described above.



the viability of wildlife populations. Body burdens ofCOECs in small mammals collected in flood plain

habitats were measured and evaluated in the context of existing toxicity information. Additionally, because

of federal listing as a threatened species, the viability of the bald eagle (Haliaeetus leucocephalus) was

assessed. To assess the health of the vascular plant communities potentially affected by chemical

contamination, the site quality indices of such communities (especially on the species richness metric) as

determined by Horton et al. (1996), was the measurement endpoint.


Spring Creek watershed soils database.

Table 6-23. Terrestrial COECs for the Spring Creek Watershed

Contaminant Maximum Concentration (mo/ko) 95% VCL (mo/ko)

J,3,5-trinitrobenzene 90 6.87

2,4,6-trio itrotoluene 85,000 752

HMX 32,000 3.060

RDX 51,000 643

Aluminum 21,000 11,730

Chromium 2,110 47.1

Iron 42,500 19,123

Lead 17.000 233

Silver 38 1.28Thallium 110 20.1Bis-(2-ethylhexyl) ohthlate 60 0.794

Iowa Army Ammunition PlantEcologicsl Risk Assessment Addendum (Draft Final)

March 27. 1998Page 6-24

Table 6-23. Terrestrial COECs for tbe Spring Creek Watersbed

Contaminant Maximum Concentration (m2lk2) 95% VCL (mI!/k2)2-methylnaphthalene 6 0.073

Benzo[deflphenanthrene 5 0.073Dj-n-butyl phthlate 6.3 0.566

These values reflect the entire watershed, and include "hot spots" such as spill areas or waste pits not

nonnally considered pathways. Therefore all potential ecological exposure pathways should be implicitly

considered. Four explosives, six metals, and four base neutral organics are identified as COECs. These

analyses represent total concentrations in soil on a dry weight basis. All data used to generate the table were

taken from the JAYCOR database provided by lAAAP to Harza.

6.3.2.2 Exposure Assessment. Section 4.3.2 provides details on computational methods used to

estimate exposures to terrestrial receptors. The assessment endpoint for terrestrial high trophic level

consumers exposed via their diet is reduced reproductive success. The measurement endpoint is body

burdens of COECs in prey. The white-footed mouse was principally used to estimate the COEC body

burdens in small mammals in the Spring Creek watershed.

The white-footed mouse is a common raptor prey item inhabiting IAAAP floodplains. Nests may be in tree

cavities, old bird or squirrel nests, or underground beneath protective cover. Home range is generally small,

about one-fifth acre. Preferred foods ofwhite-footed mice includes insects, seeds and fruit, with the relative

amounts depending upon availability (Schwartz and Schwartz 1981).

Table 6-24 gives the estimates of the intake oftemestrial COECs by white-footed mice at three sites in the

Spring Creek watershed. SC I is upstream of lAAAP munitions areas; SC2 is at Road P and SC4 is at the

southeast boundary ofIAAAP. Full tabulation of the computations are reprinted in Appendix C.

Table 6-24. Estimated Mouse Doses (mj!/k2/d)

COEC SCI SC2 SC4

1,3.5-Trinitrobenzene 2.4E-Ol 2.4E-OJ 1.5E-Ol

2,4,6-Trinitrotoluene 7.1E-04 7.1E-04 4.9E-04

HMX l.lE-Ol l.lE-OI 5.0E-02

RDX 4.0E-01 4.0E-01 1.9E-01

Aluminum 4.9E+Ol 4.9E+Ol 3.7E+01


March 21. 1998Page 6-25

Table 6-24. Estimated Mouse Doses lml!/k2Id)

COEC SCI SCl SC4

Chromium 8.3E-02 8.9E-02 3.0E-02

Iron 7.3E+Ol 8.9E+OJ 6.5E+Ol

Lead 1.8E-OJ 4.5E-Ol 9.2E-02

Silver I.5E-02 I.5E-02 1.6E-02

Thallium I.3E-02 6.8E-03 6.6E-03

Benzoldeflnhenanthrene 2.3E-04 2.3E-04 8.0E-04

Dj-n-butyl phthalate 4.5E-04 4.5E-04 8.4E-03

2-Methvlnaphthalene 5.6E-04 5.6E-04 1.7E-03

Within the Spring Creek watershed, no terrestrial COECs that would biomagnifY were identified. To

confirm that bio-magnification of COECs is not posing significant risk to resources of special concern, these

chemicals in were measured in eagle prey (Tables 6-10 and 6-14). No detectable residues were found.

6.3.2.3 Effects. NOAEL values are shown in Table 4-30 for the white-footed mouse and for the bald

eagle for the chemicals of concern. Reference toxicity values were taken from the literature and scaled to

white-footed mice or eagles using the body weight ratio method of Sample et al. (1996).

No toxicity data could be found on 2-methylnaphthalene. A NOAEL dose for mice was derived from data

on anthracene. 2-methylnaphthalene is a methylated two-ring aromatic compound; anthracene is an

unmethylated three-ring aromatic compound. PNA toxicity tends to increase with the number of rings as well

as with alkylation (Eisler, 1987). IRIS contains a NOAEL dose for lab mice of 1000 mg/kg-d. An

uncertainty factor of 10 was assumed for transchemical extrapolation to arrive at the 2-methylnaphthalene

NOAEL dose of 100 mglkg-d.



White-footed Mouse. Table 6-25 provides NOAEL values and hazard quotients for risks to white-footed

mouse.

Table 6-25. NOAEL Values and Hazard Quotients for White-Footed Mouse

Hazard Quotients

COEC Mouse NOAEL Im~/k~/d SCI SC2 SC4

1,3,5-Trinitrobenzene 57.4 0.004 0.004 0.003


March 21. 1998Page 6-26

Table 6-25. NOAEL Values and Hazard Quotients for White-Footed Mouse

Hazard Quotients

COEC Mouse NOAEL (m./k./d SCI SC2 SC4

2,4,6-Trinitrotoluene 3.00 0.0002 0.0002 0.0002

HMX 115 0.001 0.001 0.0004

RDX 7.90 0.05 0.05 002

Aluminum 2.09 23 23 18

Chromium 6.55 om 0.01 0.005

Iron 147 0.5 0.6 0.4

Lead 15.98 0.01 0.03 0.006

Silver 0.11 0.1 0.1 0.2

Thallium 0.02 0.8 0.5 0.4

Benzoldefiphenanthrene 75.0 0.000003 0.000003 0.00001

Di-n-butvl phthalate 594 0.000001 0.000001 0.00001

2-Methylnaphthalene 100 0.00001 0.00001 000002

As many of these chemicals have different mechanisms of toxicity, summing them for estimation of a hazard

index is not appropriate. Hazard quotients greater than unity indicate a likelihood for adverse effects on the

white-footed mouse population. Aluminum HQs consistently exceed unity at all stations, including SC I, the

reference station. Aluminum is a substantial components of soil, being naturally present in IAAAP at up to

22, I00 mg/kg (JAYCOR 1996). The levels in the Spring Creek watershed soils are not elevated above

typical levels and risks, if they exist, are due to natural causes rather than lAAAP past or present operations.


community quality assessment as part of their study. Their assessment is summarized and interpreted below

as part of the ERAA. Their forest community quality index was based on vascular plants and bryophytes,

and was composed of six metrics:

I. E/T vase = number of species of federal and state endangered or threatened vascular plants, or

species previously undocumented or recorded from fewer than six Iowa counties

2. EfT bryo = number of bryophyte species previously undocumented or recorded from fewer than six

Iowa counties

3. Rare vase = number of species of vascular plants new to, and/or considered rare in Des Moines

County and/or SE Iowa

4. Rare bryo = number of species ofbryophytes new to Des Moines County


March 21, 1998Page 6-27

5. Spp Rich vase =species richness of indigenous vascular plants

6. % indig = percentage of flora comprised of indigenous vascu lar plant species

Horton et al. inventoried 30 forest community sites in, or near, the lAAAP and scored them according to the



between 0 and 5. A site quality index for each locality was then the sum ofthe class scores. The numerical

values of each metric and its class score (in parentheses), and site quality indices for these sites are given in

Table 6-26. Sites where data were insufficient to calculate a metric are denoted (ID) for that metric.

Table 6-26. Relative Quality of Forest Communities, Spring Creek Watershed, IAAAP

Locale Site Err vase Err bryo Rare vase Rare bryo Spp Rich vase % indig Index

N of Road G SCI 0 0 I (I) 0 65 (2) 84 (I) 4

S of Road G 0 0 0 0 48 (I) 83 (I) 2

N of Road P SC2 0 0 3 (I) 0 84 (2) 87 (2) 5

S of Road P I (I) 0 18 (5) 6 (3) 179 (5) 83 (I) 15

N of Road K 0 2 (3) 6 (2) 6 (3) 130 (4) 86 (2) 14

S of Road K SC4 0 0 3 (I) 0 91 (2) 83 (I) 4


condition of a site in comparison with other sites within and beyond the Spring Creek watershed. Horton

et al. classified sites having a site quality index (SQI) greater than or equal to 20 as "exceptional," and sites

with an SQI of 10-19 as "significant." Sites with SQI scores ofless than 10 were "considered of marginal


the value of a site as a natural area, it is assumed for the risk assessment that sites having current

"exceptional" or "significant" site quality indices are not degraded by chemical contamination. However,

it is also recognized that sites identified as "marginal natural areas" may have been altered from a "natural

state" by factors other than chemical contamination. Foremost among such factors would be land clearing

and agricultural activities on the IAAAP property.

As seen in Table 6-26, the sites south ofPlant Road P and north of Plant Road K represent the highest quality

forest in the Spring Creek watershed (Horton et al. 1996). The quality scores for these sites are likely related

Iowa Army Ammunition PlantEcologicsl Risk Assessment Addendum (Draft Fina/)

March 21. 1998Page 6-28

to the large size of the forest in those areas (Exhibit 3-1). Relatively small forest tracts are in the study

locales south of Road G and north of Road P. Contamination in the drainage is heaviest in the vicinity of

the Explosive Disposal Area, south of Road G/north of Road P. These are also two of the lowest quality

forests in the watershed, particularly the area south ofRoad G. Sites SC I, SC2, and SC4 have SQIs of4,2,

and 4, respectively. As such, all three areas, including the reference area are "considered of marginal value

as natural areas." Because the reference station, SCI, is not contaminated, it appears that IAAAP facility

development, through restriction of forest lot size, may be limiting forest quality to the same or a greater

degree than contamination. Forest ecology principals demonstrate that reducing tract size, while increasing

gaps or "edge" habitats, alters microclimate in the forest that affects species diversity, dominance and

abundance. Inside the tract, wind speeds increase, mean temperature increases, humidities decrease, and light

penetration increases. All these factors reduce forest quality, and at IAAAP, are more likely affecting forest

community structure than industrial contamination.

6.3.2.6 Uncertainty. Several assumptions or procedures used in this risk assessment are a source of

uncertainty.

• The prescreening process using detection frequencies and benchmark criteria should not be

significant contributor to uncertainty. All data in the watershed was used, including "hot spots" to

narrow the number of chemicals to the COEC list addressing in this chapter. The procedure should

not have eliminated any COECs. In some respects, this opinion is supported by the field

measurements because biomagnirying contaminants in mammal tissue samples are below method

detection limits.

• The terrestrial exposure assessment was limited to three stations in the watershed, one of which was

intended to serve as a reference. Characterization of the watershed on the basis of three stations

poses some uncertainty. While the number of sources of contamination in the Spring Creek

watershed, previous studies on ecological stress, and budgetary factors were contributors to the use

of three exposure sampling stations, this does increase uncertainty for the basin.

• The findings appear to be sound because biomagnirying COECs were not detected (or detected at

levels near the MDL) in fish, mammal or soil matrices at any stations in the watershed. In all cases,

conservative assumptions were used in order to minimize uncertainty. Contaminant intake factors

accounted for the diversities of diet in the white-footed mouse.

Iowa Army Ammunition PlBntEcological Risk Assessment Addendum (Draft Final)

March 21. 1998Page 6-29

• NOAEL RTVs were chosen for use rather than LOAEL or other endpoints in the estimates. This

reduces uncertainty about individual survival of species of special concern. All NOAEL dose

estimates contain uncertainty factors (Sample et al. 1996). In the estimation of a NOAEL dose for

2-methylnaphthalene, an uncertainty factor of 10 was applied to the NOAEL dose for anthracene.

• The uncertainty related to the forest community quality index prepared by Horton et al. is considered

to be moderate to low. The inclusion of six metrics in the index broadens its reliability as an


6.3.2.7 Summary of Terrestrial Risks. There is no evidence that IAAAP operations are significantly

impacting ecological resources ofthe Spring Creek watershed. The forest community assessment is the most

reliable measurement endpoint for terrestrial risk. Areas south of Plant Road P and north of Plant Road K

represent the highest quality forest in the Spring Creek watershed, and are likely related to the large size of

the forest in that part ofthe IAAAP property. Relatively small forest tracts are in areas south of Road G and

north of Road P. Contamination in the drainage is heaviest in the vicinity of the Explosive Disposal Area,

that is, south of Road G/north of Road P. These are also two of the lowest quality forests in the watershed,

particularly the area south of Road G. However, because forest quality at the uncontaminated reference site

is also low, it appears that IAAAP facility development, through restriction offorest lot size, may be limiting

forest quality to the same or more degree as contamination.


March 21, 1998Page 6·30

7.0 SKUNK RIVER WATERSHED



The Skunk River is located just south of the lAAAP and flows from north-northwest to south-southeast to

the Mississippi River. Within lAAAP, the Skunk River and is fed by several unnamed tributaries that

originate on site, as well as Long Creek. The Skunk River has a drainage area of about 2,500 acres within

the southwestern part of the IAAAP characterized by steep, wooded terrain.


Land uselland cover in the Skunk River watershed at IAAAP is primarily upland forest (Exhibit 3-1), as

summarized in Table 7-1.

Table 7-1. Land UselLand Cover in the Skunk River Watershed at IAAAP

Land Use/Cover Type Acres Percentage

Uoland Forest 1,441 58%

Floodplain Forest 72 3%

Old Field 258 10%

Other Wetland 0 0%

A2riculture 412 16%


Open Water, PondlLake 5 0%

Residential 0 0%


Base FacilitiesfOld Fields 192 8%

Total 2,499 100%

In 1996, an inventory and assessment of habitats and biota of the IAAAP was published (Horton et al.).

While their objective was to assess the entire facility, they focused on natural areas along creeks and

drainageways, where temperate deciduous forest predominates. The current flood plain forest is in early

successional sere and is characterized by the dominance of cottonwood (Populus deltoides), black willow

(Salix nigra), sycamore (Platanus occidentalis), honey locust (Gleditsia triacanthos), green ash (Fraxinus



pennsylvanica), northern hackberry (Celtis occidentalis), elm (Ulmus spp.), poison ivy (Rhus radicans),

grape (Vitus spp.), multiflora rose (Rosa multiflora), brambles (Rubus spp.), and numerous species offorbs,

grasses and sedges (Horton et al. 1996).

7.1.3 Biological Resources

As mentioned earlier, the bald eagle (Haliaeetus leucocephalus) has been recorded in the Long Creek

watershed. Horton et al. (1996) reported no federally listed endangered species on the lAAAP property, but

did find six state-threatened species of plants and one state-listed threatened fish species. Five state

threatened species ofplants were found by Horton et al. in the Skunk River watershed. The locations of all

biological resources of special concern within the watershed are provided in Table 7-2.

Table 7-2. Protected Species in the Skunk River Watershed

Locality Species

Creek 1 1/4 mi W of Augusta Main Rd Virginia-snakeroot (Aris/o/achia serpentaria)SEJ/4, Sec. 14, T69N R4W sharpwing monkey-flower (Mimulus alatus)

false hellebore (Veratrum woodii)

Creek I 1/5 mi W of Augusta Main Rd Virginia-snakerootNWI/4 ofSW1/4, & WI/2 ofNE 1/4, Sec. 14, T69N R4W false hellebore

Creek 2 mi W of Augusta Main Road Virginia-snakerootN 1/2, Sec. 15 & Sec. 10 mainly S 1/2, T69N R4W false hellebore

W of Creek 2 mi. W of Augusta Main Road bald eagleNW 1/4 ofSE 1/4, Sec. 15 T69N R4W

Upland W of Creek I 1/4 mi W of Augusta Main Road; SE sedge (Carex umbel/ata)1/4, Sec 14, T 69N, R4W ragged fringed orchid (Platanthera lucero)

7.1.4 Geology and Hydrology

Surface water drainage directly to the Skunk River occurs in the southwest comer of the lAAAP,

Physiographically, this area is characterized by a bluff descending from uplands at Line 3A and the

Demolition Area down to the flood plain of the Skunk River. The bluff face is dissected by several small,

unnamed tributary streams and generally is wooded, Relatively few soil borings are available within this area

because of the relatively steep terrain, Borings available above the bluff indicate the bedrock is relatively

high and the glacial drift relatively thin, generally less than 25 feet thick, with limestone bedrock exposed

intermittently along the base of the bluff. Shallow groundwater flow is generally southwestward in the drift


March 20, /998Page 7-2

and the bedrock, discharging to the small unnamed creeks and directly to the Skunk River alluvial valley.

7.1.5 Facilities

The lAAAP facilities in the Skunk River drainage area include Line 3A, Line 3A Sewage Treatment Plant,

Line 3A Pond, and the Demolition ArealDeactivation Furnace.

Table 7-3. Facilities in Skunk River Watershed

Facility Sizel Period of Function WastewaterlWaste ContaminantsBldg. Operation

Line3A 119 1943-1945, Explosives-related Explosives contaminated wastewater is Explosivesacresl17 1949-1989, processing, loading, processed through a carbon filter, Metalsbldgs recently assembly, and packing. discharged (NPDES #34) tn a tributary PCBs

reopened Presently. production of the of the Skunk River.Volcano anti-tank mine.

Demolition 10 acres DA - early DA- open detonation of Metal and collectable residue after ExplosivesAreal 1940s to reject ammunition. DF- detonation are collected and treated MetalsDeactivation present; used for destruction of elsewhere, scrap sold as salvageFurnace DF - 1971 small explosive-loaded material, unsalvageable metal and ash(DAlDF) 1980 and components. are containerized in steel dumpsters and

1983 to stored as hazardous waste (D006). Ashpresent collected from air pollution control

system consists of 0004, 0006. 0007,and 0008 waste.

Line3A 1/2 acres 1943-1945, Treatment of domestic Effluent from plant flows into ExplosivesSewage 1949- late waste and blowdown water intennittent stream west of site via MetalsTreatment 1980s from steam generating NPDES outfall (#014) which eventuallyPlant plant. drains into the Skunk River.

Lioe 3A Pond 60 by 30 1956-1958 Approximately 15,000 The waste was the result of a metal Metalsby 8 ft or 1959 gallons of spent sulfuric cleaning operation. The pit was

and hydrochloric acid were excavated and soils disposed in basedisposed in pond and landfill.neutralized with sodiumhydroxide.



7.1.6 Sources of Contamination

7.1.6.1 Soils. Table 7-4 summarizes soil contamination in samples collected by JAYCOR (1996) and

Harza (1997a). Line 3A, previously described in Section 5, under the Long Creek Watershed, is repeated

because part of Line 3A is in the Skunk River Watershed. Contamination in this watershed is of particular

concern due to the proximity to the lAAAP property boundary.

Table 7-4. Soil Contamination in Long Creek Watershed


Line 3A · 2,4,6-TNT and RDX were detected in soils near Line 3A at levels up to 19,000 and 11,000 ltg/g,respectively. HMX was detected at levels up to 1700 ltg/g. 1,3,5-TNB was detected as high as 2lltg/gwhile 2,4-DNT was detected up to 13.2 ltg/g. Minor contamination by 1,3-DNB, 2,6-DNT andnitrobenzene were also detected. The majority of explosives were detected around Building 3A~05-1

and its associated buildings (3A.140-3, 3A-140-7 and 3A-70-1). Explosives were reported in thedrainage ditches leading southeast and off-site from Line 3A The RI reported a trend for explosivesconcentrations to decrease with depth JAyeOR (1996). The levels of detectable contaminants decreaseswith distance from the identified source areas such as sumps and loading areas.

· Barium and lead were detected at levels up to 341 and 1710 Ilglg, respectively. Arsenic detected atlevels up to 15 ltg/g, chromium at levels up to 223 ltg/g, silver at levels up to 370 ltg/g, mercury andselenium at levels up to 4 and 2.53 j.lg/g respectively. The areas with the highest metals levels are theBuilding 3A-05-1 area and the area northwest of Building 3A-05-2.

• Previous soil gas sampling south ofbuiling 3A·03-01 indicated VOCs (6.5 mg/kg at5 ft). In Spring1997, detections in soil samples included J, 1,2-Trichlorofluoroethane (3.6 mglkg), and concentrationsunder 1.0 mg/kg for other VOCs (Harza I997a).

· PCBs detected in one sample collected at the NPDES discharge point at Building 3A-05-2, at levels lessthan 10 ltg/g.

DAlDF · Low levels of explosives were found in one of 10 samples during the RI.

· Of 21 soil samples collected during the RI, all had detectable levels of arsenic, barium, chromium, andlead with maximum values of 13, 5100, 613, and 6400 ltg/g, respectively. Twelve samples reporteddetectable levels of mercury with a maximum value of 0.91 j.lg!g, 10 reported cadmium with a maximumvalue of J80 j.lg!g, and four reported selenium with a maximum value of 2.06 j.lg/g.

Available data at Line 3A Sewage Treatment Plant and Line 3A Pond did not indicate significant

contamination.

7.1.6.2 Surface Water and Sediments. Four intermittent streams flow from Line 3A; three flow for

approximately one mile to Skunk River and one for one-half mile in a northerly direction, discharging to

Long Creek. Surface water and sediments were sampled at two locations designated 7P and 7Q on Exhibit

4-2, on two of these tributaries (Harza 1997a). The 7P tributary drains parts of the Demolition Area. No

explosives were detected in either the surface water or the sediment sample from this location. The 7Q

tributary drains parts ofLine 3A. No explosives were detected in the sediment sample. However, 9.4 flg/L



total explosives were detected in the surface water. Arsenic was above action levels (3.8 mg/kg) in both

sediment samples from both sites. The source ofthe surface water contamination is not known, but may be

due to NPDES discharges or migration of groundwater from Line 3A. Sampling results for surface water

are shown in Table 7.5; and for sediments, in Table 7·6.

Table 7·5. Resulls of Surface Water Sampling in Skunk River Watershed

Sampling VOCs SVOCs Explosives Metals>WQSLocations 1I1g1L) (ltgIL) (ltg/L)

7P Methylene chloride (3.1) None None None

7Q Methylene chloride None RDX (7.8); HMX (1.6) None(7.98)

B - Detected In blank as well as sample.

Table 7-6. Results of Sediment Sampling in Skunk River Watershed

Sampling VOCs SVOCs Explosives Metals Exceeding EcotoxLocations (ltg/kg) (ltg/kg) (ltg/kg) Criteria (mg/kg)

7PI (I ft) Methylene chloride (6.18) None None Arsenic (23.1)

7QI (I ft) Methylene chloride (12.78) None None None

7.1.6.3 Groundwater. Table 7-7 summarizes detections of chemical parameter groups in samples from

facilities drained by the Skunk River.

Table 7-7. Contaminants of Concern Detected in Groundwater


Line 3A x x x

DAlDF x x

Line 3A Sewage Treatment Plant Inactive, not sampled

Line 3A Pond Not sampled

The following paragraphs highlight results of sampling as reported by JAYCOR (1996). Concentrations

indicate the highest level reported within each facility or area.

Iowa Army Ammunition Plant March 20, 1998Ecological Risk Assessment Addendum (Draft Finall Page 7-5

At Line 3A, low levels of explosives have been reported in one deep well and four shallow wells located

within the Skunk River watershed. The maximum concentration reported was 39.7 IlgIL for RDX. At the

Demolition Area/Deactivation Furnace, all six of the wells sampled reported low levels of explosives in the

groundwater. The maximum concentration reported was 13.7 IlgIL for RDX.

Metals detected in Line 3A wells in the Skunk River watershed include chromium (53 IlgIL), lead (15.1

IlgIL), arsenic (2.22 IlgIL), and vanadium (79.8 IlgIL). At the DA/DF, three wells were reported to contain

chromium (66.5 IlglL) and lead (11.3 IlgIL) above detection limits.

7.1.6.4 NPDES Discharges. Permitted outfalls in the Skunk River drainage area are presented in Table

7-8.

Table 7-8. Currently Permitted NPDES Discharges to Skunk River

Outfall No. Location Remarks Monitoring Parameters

14 Line3A, Bldg. 500-216-2 3A sewage plant outfall. Flow, pH, BOD/COD, TSS, Ag

34 Line 3A, Bldg. 3A-70-1 Discharge from explosive Flow, pH, RDX+HMX, TNT, TSSloading operations.

The effluent limits for the outfalls to Skunk River are shown in Table 7-9.

Table 7-9. NPDES Effluent LimitationsConcentration Mass

Wastewater Season Average Average DailyParameters 7Dav 30Dav Daily Max. Units 7Dav 30Dav Max. Units

Flow Yearly 0.04 (14) 0.07(14) MGD0.093

Total Yearly 20.00 40.00 mg/L 16.00 31.00 Ibs/daySuspended 45.0 (14) 30.0 (14) 15.00(14) 10.00(14)SolidsCBOD5 Yearly 40.0 25.00 mg/L 13.00 8.00 Ibs/daynH Yearly 6.00 9.00 STDTrinitrotoluene Yearly 0.33 1.00 mg/L 0.26 0.77 Ibs/dayRDX+HMX Yearly 0.75 2.25 mglL 0.58 1.75 Ibs/daySilver Yearly 0.036 0.055 mg/L 21.00 32.00 .001

Ibs/dav



March 20. 1998Paga 7-6

Aquatic macroinvertebrates were the only biota sampled by Harza in this watershed. Sampling was

performed in accordance with the RBP as discussed in Section 3.8. Two tributaries of the Skunk River in

the southwest part ofthe IAAAP were compared to the Long Creek reference station. Number and species

ofmacroinvertebrates collected at the two stations in the watershed (SRTI and SRT2) and the HBI tolerance

values for all taxa are presented in Appendix F. There were qualitative differences between the

macroinvertebrate communities in the tributaries, used as the basis for the community assessment. Taxa that

accounted for most of benthos were:

chironomid midge larvae

hydropsychid caddis fly nymphs

asellid isopods

12%

23%

18%

6%

66%

2%

These taxa are fairly tolerant ofpollution. Tolerance values vary from 0 (intolerant, sensitive) to 10 (highly

tolerant). Hydrophychids have a tolerance value of4; chironomids 6; and asellids, 8.


The ecological risk within the Skunk River tributaries watershed is assessed separately for aquatic and

terrestrial ecosystems. The data from both Harza and JAYCOR databases, are used to develop exposure

scenarios for ecological receptors on the IAAAP property.


The aquatic assessment endpoint for the Skunk River watershed is health ofthe benthic macroinvertebrate

community. The measurement endpoint is the result of the Rapid Bioassessment Protocol III developed by

the USEPA (Platkin, et aI. 1989). The results ofthe Rapid Bioassessment in the Skunk River tributaries are

provided below (Table 7-10). The small streams in this watershed originate on the IAAAP property and have

contaminated areas in their headwaters. Therefore, no reference site is available within the watershed and

the reference site used for Long Creek watershed was selected for use in this watershed.

In comparison to the reference station (LCI), SRTI was rated as unimpaired and SRT2 was rated as slightly

impaired. The principal difference affecting the ratings was the abundance of EPT (Ephemeroptera,


Merch 20. 1998Page 7-7

Plecoptera, Tricoptera) taxa. Twelve baetids, 28 hydropsychids and II hydroptilids were collected from

SRTI. Respective totals for SRT2 were 0, 2 and I, lowering the score for this site. Because of the low

variability in the metrics utilizing EPT abundance and the high sensitivity of these taxa to contamination, the

benthic community at Station SRT2 is likely environmentally stressed. However, that stress could result

from poor habitat quality and intermittent flow as well as chemical contamination. IdentifYing the likely

cause of the stress at Station SRT2 cannot be clearly determined from a comparison with the reference

station, but such a comparison suggests physical habitat and flow to playa major role.

Table 7-10. Rapid Bioassessment Protocol III for Skunk River Watershed

Station No. LCI SRTI SRT2Watershed Long Cr. Skunk River Skunk RiverSource of Sample Long Cr. Tributary TributaryM I ~ Species Richness 11 12 10

Biological Condition Score 6 6 6

M2 - HB1 (modified) 7.5 5.3 7.2

Biological Condition SCOfe 6 4 6

M3 • ScraperslFiltering Collectors 0.32 0.06 5.00


M4 • EPT/Chironomidae 2.14 2.83 0.43


M5 - % Dominant Taxon 75% 25% 66%Biological Condition Scofe 0 2 0

M6 - EPT Index 3 3 2


M7 - Community Loss 0 0.33 0.30


M8 -Shreddersrrotal 60% 43% 92%


% Comparison to Reference Score 100% 86% 7]%

Biological Condition Category Reference Unimpaired Slightly impaired

The reference station, LCI is located at the western boundary ofIAAAP. While riparian habitat between

the reference site and evaluation sites was similar, upstream land use at LC I is intensive agriculture. Land

use in the Skunk River tributaries watersheds is principally forest (Table 7-1). However, physical habitat

differences between LC I and the Skunk River tributary sites were apparent, primarily due to the greater

flows at LCI (Appendix E). This suggests that flow plays a major role in any environmental stress at Station

SRT2.




The risk assessment endpoints for the terrestrial ecosystem are the health of the vascular plant community

and the viability of wildlife populations. Body burdens ofCOECs in small mammals found in flood plain

habitats were estimated and evaluated in the context of existing toxicity information. Small mammals,

however, were not captured or analyzed in this watershed. Because offederal listing as a threatened species,

the viability of bald eagle (Haliaeetus leucocephalus) individuals also was assessed. To assess the health

of the vascular plant communities potentially affected by chemical contamination, the site quality indices

of such communities (especially the species richness metric) as determined by Horton et al. (1996), was the

measurement endpoint.


Skunk River tributaries watershed soils database. The values shown in Table 7-11 are for the entire

watershed, and include "hot spots"such as spill areas or waste pits not normally considered pathways.

Therefore all potential ecological exposure pathways should be implicitly considered. One explosive, five

metals, two pesticides (both ofwhich biomagniry) are listed. All data used to generate the table were taken

from the JAYCOR database provided by IAAAP to Harza.

Table 7-11. Terrestrial COECs for the Skunk River Tributaries Watershed

Contaminant Maximum Concentration (mg/kg) 95% VeL (mg/kg)

RDX 0.49 0.44

Aluminum 16,500

Chromium 22.4 16.8

Iron 32,600 27.667

Lead 36

Silver 15.5

DDE (biomagnifier) 0.004

DDT (biomagnifier) 0.047

Note: COECs without 95%UCL represent a smgle measurement.

7.3.2.2 Exposure Assessment. Soil exposure point concentrations for COECs in the Skunk River

watershed (Appendix B) were used to estimate COEC doses to white-footed mouse and bald eagle. The

procedures and assumptions for the estimation process are presented in Section 4.3.2 and complete

documentation is provided in Appendix C. Where only a single sample result was available for a COEC, that

concentration was used for the exposure point concentration. No samples were collected in the vicinity of



SRTI, and data from SRTl were used as the basis for the exposure assessment. COEC dose estimates for

the white-footed mouse are provided in Table 7-12.

Table 7-12. Dose Estimates ofCOECs to White-footed Mouse (ml!!kl!-d)

COEC Ve2etation Invertebrates Soil Water Total

RDX 0.393 0.00001 0.001 0.01 0.404

Aluminum 1.165 0.0005 41.757 0.1 43.0

Chromium 0.017068 0.00003 0.05791 0.0 0.075

Iron 8.755 0.0476 89.11 0.1 97.93

Lead 0.17492 0.00001 0.099 0.0003 0.2741

Silver 0.014309 0.00001 0.000910 0.0002 0.0154

4.4'-DDE 0.000009 0.00003 0.00001 0.0 0.00005

4,4'-DDT 0.000108 0.00007 0.00015 0.0 0.00033

To confirm that biomagnification ofCOECs in the Skunk River tributaries watershed is not posing significant

risk to resources of special concern, potential doses ofbiomagnifying COECs to individual bald eagle were

also estimated. Eagle standard reference values were tabulated in Table 4-28, taken from USEPA (1993).

Appendix C also documents dose estimates ofbiomagnifying COECs (pesticides, as identified in Table 7-11)

to the bald eagle. Table 7-13 below provides daily intake estimates for the bald eagle.

Table 7-13. Bald Eagle Dose Estimates (mg/kg/d)

COEC Food Water Soil Total

DDE 0.0000003 0 0.000009 0.00001

DDT 0.000001 0 0.0001 0.0001

7.3.2.3 Effects. NOAEL values for white-footed mouse and bald eagle for chemicals of concern at

IAAAP are found in Table 4-29.



White-footed Mouse. Table 7-14 provides NOAEL values and hazard quotients for risk to white-footed

mouse in the Skunk River tributaries watershed. As many ofthese chemicals have different mechanisms of

toxicity, summing them for estimation of a hazard index is not appropriate.


March 20. 1998Page 7·10

Table 7-14. NOAEL Values and Hazard Quotients for White-footedMouse in Skunk River Tributaries Watersbed

COEC NOAEL (m~/k~/d) Hazard OuotientRDX 7.90 0.05

Aluminum 2.Q9 21

Chromium 6.55 0.01

Iron 147 07

Lead 16.0 0.02

Silver 0.11 0.1

4,4'-DDE 1.60 0.00003

4,4'-DDT 1.60 0.0002

The only HQ greater than unity is for aluminum. JAYCOR defined background aluminum concentrations

in lAAAP soils to be as high as 22, I00 mglkg. The 95%UCL aluminum concentration for the Skunk River

tributaries watershed is 13,509 mg/kg, well within the range of natural values. Therefore, if risks from AI

are apparent at this site, they are due to natural causes, not IAAAP historical or ongoing operations.

NOAEL values and hazard quotients (HQs) for biomagnirying COECs consumed by bald eagle in the Skunk

Creek watershed are presented in Table 7-15.

Table 7-15. NOAELs and HQs for Bald Eagle

COEC NOAEL (mglkg/d) Hazard Quotient

DDE 00030 0.003

DDT 0.0030 0.04

HQs for both chemicals are considerably below the level of concern. Therefore, no significant risk to bald

eagle is estimated from the biomagnifiers DDT or DDE in the Skunk River tributaries watershed. In use of

50% of the MDL for COEC concentration, it does not appear that bald eagle viability or reproductivity is at

any significant risk in the Skunk River watershed. Although may bald eagles feed south of the IAAAP along

the Skunk River, the exposure modification rate (EMR) is likely to be no more than 0.05.


community quality for IAAAP, summarized in this section and and interpreted as part of the ERAA.

Horton's forest community quality index was based on vascular plants and bryophytes, and was composed

of six metrics:


March 20. /998Page 7-//

I. Err vase =number of species of federal and state endangered or threatened vascular plants,


2. Err bryo =number ofbryophyte species previously undocumented or recorded from fewer


3. Rare vase = number of species of vascular plants new to, and/or considered rare in Des


4. Rare bryo =number of species ofbryophytes new to Des Moines County

5. Spp Rich vase = species richness of indigenous vascular plants

6. % indig =percentage of flora comprised of indigenous vascular plant species

Horton el al. inventoried 30 forest community sites in, or near, the lAAAP and scored them according to the



between 0 and 5. A site quality index for each locality was then the sum of the class scores. The numerical

values of each metric and its class score (in parentheses), and site quality indices for these sites are given in

Table 7-16.

Table 7-16. Relative Quality of Forest Communities, Skunk River Watershed

Locale EIT vase EIT bryo Rare vase Rare bryo Spp Rich vase % indig Index

Creek 1 mi E of Augusta 0 2 (3) 3 (I) 4 (2) 77 (2) 96 (I) 13

Creek W of Augusta 0 3 (5) 4 (I) 4 (2) 107 (3) 91 (I) 14

Creek I 1/4 mi W of Augusta 4 (5) I (I) 19 (5) 5 (3) 200 (5) 94 (4) 23

Creek 1.5 mi W of Augusta 2 (2) 2 (3) 9 (3) 9 (5) 139 (4) 95 (5) 22

Creek 2 mi W of Augusta 2 (2) I (I) 19 (5) 7 (4) 179(5) 91 (3) 20


condition of a site in comparison with other sites within and beyond the Skunk River watershed. Horton el

al. classified sites having a site quality index (SQI) greater than or equal to 20 as "exceptional," and sites

with an SQI of 10-19 as "significant." Sites with SQI scores of less than 10 were "considered of marginal


the value of a site as a natural area, it is assumed for the risk assessment that sites having "exceptional" or

"significant" site quality indices are not degraded by chemical contamination. However, it is also recognized


March 20, 1998Page 7-12

that sites identified as "marginal natural areas" may have been altered from a "natural state" by factors other

than chemical contamination. Foremost among such factors would be land clearing and agricultural activities

on the IAAAP property, and increasing the relatively proportion of "edge" habitat..

The forest communities in the small drainages to the Skunk River are some of the highest quality forests on

the IAAAP. SQI values indicate "exceptional" forest communities at three sites and "significant"

communities at the other sites surveyed. Several State-protected plants are recorded in the watershed (Table

7-2) and are not being threatened by ongoing IAAAP operations.

7.3.3 Uncertainty

The risk assessment, overall, has a moderate degree of uncertainty associated with it. Several assumptions

or procedures used in this risk assessment are a source of uncertainty. In our view, the pre-screening process

using detection frequencies and benchmark criteria is not a significant contributor to uncertainty. All data

in the watershed was used, including "hot spots" to narrow the number of chemicals to the COEC list

addressing in this chapter. The procedure should not have eliminated any COECs. In other watersheds of

IAAAP, this opinion is supported because field measurements of biomagni1'ying contaminants in mammal

tissue samples are below method detection limits. More significant sources of uncertainty are:

• The terrestrial exposure assessment was limited to one site in the watershed. Even so, the

assessment reasonably reflects exposure pathways and contaminant concentrations across the

watershed and only contributed in a minor way to uncertainty.

• NOAEL RTVs were chosen rather than LOAEL or other endpoints for the estimates. NOAEL dose

estimates contain uncertainty factors (Sample et al. 1996).

• The uncertainty related to the forest community quality index prepared by Horton et al. is considered

to be moderate to low. The inclusion of six metrics in the index broadens its reliability as an


• In all cases, conservative exposure assumptions were made in order to minimize uncertainty.

Contaminant intake factors accounted for the diversities of diet in the white-footed mouse as well

as the bald eagle. Exposure modification rate was selected as 1.0 for mouse and 0.05 for bald eagle,


Msrch 20. 1998Psg. 7-13

the latter being quite conservative, as no foraging habitat for bald eagle exists in the Skunk River

tributaries watershed. Eagles in the area forage along the Mississippi River, the Skunk River and,

occasionally, Mathes Lake.

• The level of uncertainty associated with the aquatic risk assessment is low to moderate. The

principal factor contributing to uncertainty is the use of LC I as the reference station. While riparian

habitat between the reference site and evaluation sites was similar, there is greater flow at Station

LC I. Flow appears to playa major role in any environmental stress at Station SRT2.

7.3.4 Summary of Risks

The two tributaries subjected to the aquatic risk assessment using the RBP were SRTI, rated as unimpaired,

and SRTI, rated as slightly impaired. Evidence indicates that the low-level environmental stress degrading

SRT2 is likely due to poor habitat quality and intermittent flow, as opposed to chemical contamination.

Identifying the exact cause of the slight stress at Station SRT2 cannot be clearly determined from a

comparison with the reference station, LC I, but such a comparison suggests physical habitat and flow to play

a major role.

No risk is apparent to small mammals, as assessed for white-footed mice. Further, no significant risk to bald

eagle exists from exposure to DDT or DOE in the Skunk River tributaries watershed.


March 20. /998Page 7-14

8.0 BASEWIDE RISKS

This chapter addresses basewide ecological risk issues that fall outside of the watershed-based

approach presented thus far. Below we address the project remediation goals (PRO) that were

derived from human health risk estimates and non-ecological ARARs. Following that, we present

an analysis ofpotential risks to ecological receptors with non-watershed-based home ranges. Lastly,

a Conclusions section presents an overall apprisal ofecological risks ofpast and ongoing operations

atIAAAP.

8.1 Project Remediation Goals IPRGsl

The IAAAP PROs for soil and water are based on protection of human health. The primary background

document establishing these PRGs is the Revised Draft Final Remedial Investigation Risk Assessment

(Volume I I of II) prepared for the U.S. Army Environmental Center by JAYCOR and ICAIR Life Systems,

Inc.

8.1.1 Soil

Soil PRGs established for protection of human health or groundwater contamination are compared to

available ecological screening criteria in Table 8-1. Chemicals found in soil at concentrations exceeding the

ecological screening criteria should be considered as contaminants of potential concern, but may not

necessarily indicate that ecological risks exist.

This screening level review ofthe soil PRGs finds that several contaminant PRGs exceed available ecological

screening benchmarks. In such instances, COECs at the remediated sites may continue to pose risk to

ecological receptors, and justify additional ERA on a case by case basis. Consequently, a supplemental

conceptual site model was specifically developed for two recently constructed phytoremediation wetlands.

We modified the risk models developed in the preceding chapters to further assess the ability of the soil

PRGs to protect ecological receptors at the lAAAP. Pathways and receptors of concern were, specifically:



Table 8-1. Comparison of Soil PRGs (in me;/k2) for the IAAAP with Ecoloe;ical Screenine; BenchmarksORNL Terrestrial

BTAG BTAG ORNL Invertebrates BTAG EcotoxChemical PRG Flora Fauna Flora and Microorganisms Sediment' Sedil"ent

Antimonv 816 0.48 0.03 5 150Arsenic 30 328 10 60 8.2Bervllium 5 0.02 10Cadmium 1,000 2.5 3 20 5.1Chromium VI 10,000 0.02 0.008 I (total Cr) 0.4 (total Cr) <81 81Lead 1,000 2 0.01 50 500 46.7 47Thallium 143 0.001 IBenzo(a)anthracene 8.1 0.1 0.261Benzo(a)pvrene 0.81 0.1 0.43Benzo(b)fluoranthene 8.1 0.1 3.2Dibenz(a,b)anthracene 0.81 0.1 0.063Total PCBs 10 0.1 40 0.0231,3,5- Trinitrobenzene 1022,4-Dinitrotoluene (2,4- 8.7DNT)2,4,6-TNT 47RDX IHMX 51,000

Radionuclides PRG(pCi/e;)

Actinium 228 0.014Bismuth 214 0.008Potassium 40 0.74

Sediment benchmarks are nonnalized to 1% TOC in sediment. Ifthe sediment contains 5% TOC, then the benchmark wouldbe five times higher.



• Small mammals colonizing remediated upland habitats, where soil contaminants and

their concentrations are the soil PROs shown in Table 8-1. Mammals receive doses

from soil, vegetation, and invertebrate ingestion.

• Myotis bats feeding over remediation wetlands on insects. Bat dose is derived from

the ingestion ofaquatic insects hatched in the wetland, where the sediment contains

the soil PROs.

The EMR for both exposure scenarios is 1.0, that is, all feeding occurs in habitats contaminated at the PRO

levels. Water doses were ignored.

Table 8-2 includes the results of the upland scenario. Hazard quotients exceeding unity may present adverse

effects to white-footed mice or comparable species. COECs that are shown in this model to present a

significant possibility of affecting small mammal populations are antimony, arsenic, cadmium, chromium

VI, thallium, TNB and HMX. The use ofNOAEL values assures conservative estimates.

Table 8-2. Soil PRG Risk to Small Mammals

COEC Soil PRG (uglkg) Total Dose (mglkg/d) NOAEL (mg/kg/d) HazardQuotient

Antimonv 816,000 22 0.13 179

Arsenic 30,000 0.2 0.13 2

Bervllium 5,000 0.02 1.32 0.02

Cadmium 1,000,000 70 1.85 38

Chromium VI 10,000,000 40 6.06 7

Lead 1,000,000 9 15.98 0.5

Thallium 143,000 0.5 0.02 34

Benzo(a)anthracene 8,100 0.03 75 0.0003

Benzo!a)ovrene 810 0.003 1.0 0.003

Benzo(b)fluoranthene 8,100 0.03 1.0 0.03

Dibenz(a,b)anthracene 810 0.003 1.0 0.003

PCB 10,000 0.03 0.06 0.5

1,3,5·Trinitrobenzene 102,000 100 57.40 2

2,4-Dinitrotoluene 8,700 0.03 13.50 0.002

2,4,6-Trinitrotoluene 47,000 0.1 3.00 0.05

RDX 1,000 1.3 7.90 0.2

HMX 51,000,000 17,504 115 152



Table 8-3 includes the results of the remediation wetland scenario. Hazard quotients exceeding unity may

present adverse effects to Myotis bats. COECs that are shown in this model to present a significant

possibility ofadversely affecting bats are antimony, cadmium, chromium VI, thallium, benzo(a)anthracene,

benzo(a)pyrene, benzo(b)fluoranthene, dibenzo(a,b)anthracene, and PCB. The PRGs for explosives, which

are the principal driver to remediation of most contaminated soils, are sufficient to protect bats and small

upland mammals. The use ofNOAEL values assures conservative estimates.

Table 8-3. Soil PRG Risk to Bats

COEC HazardBat Dose (mg/kg/d) NOAEL (mglkg/d)

Ouotient

Antimonv 4 0.177 25

Arsenic 0.09 0.178 0.5

Bervllium 0.17 1.73 0.1

Cadmium 30 2.52 12

Chromium VI 10 8.57 1.2

Lead 15 21 0.7

Thallium 2 0.020 83

Benzo(alanthracene 101 25 4

Benzo(a)ovrene 47 1041 33

Benzo(blfluoranthene 3159 25 125

Oibenz(a,blanthracene 42 1041 30

PCB 6676 0.08 80,000

1,3,5-Trinitrobenzene 0.22 75 0.003

2,4-0initrotoluene 0.034 17.7 0.002

2,4,6-Trinitrotoluene 0.022 3.94 0.006

RDX 0.046 lOA 0.004

HMX 1.5 151 0.01

8.1.2 Water

Groundwater PRGs established for protection of human health are compared to available NOAEL criteria

developed earlier for protection of orangethroat darters in Table 8-4. Chemicals found in groundwater at

concentrations exceeding the NOAEL criteria do not generally pose a hazard to ecological receptors. The

exception to this occurs when groundwater discharges to surface streams or wetlands. In these cases, if the



Table 8-4. ComparisonofGround~ater PRGs(in /lglL)to Iowa ~tandarlls and N().4.E;LC::riteJia for Pro!ection ofl)arters_

Contaminant I _PIlG _ n10wa CWQS (LR) I NOAEL_ __ _ _J__ _BlIckground Range-- _---------_ .. _--------- --- - - - .. .._,' - - __ .- . _. -- . ,._. - . -- -- _._. . .. - _.- _.. . ---'-- ---,------

INORGANICS

------

----------

- 1--

-- --1- ----

L _ _ -:-T_- -- ---~ -----JI

II

25

~~~--=-:-~==L---------- ---620

4.900

_______2,200'----__

1 - ----

620 _1_ -- _ -.- _ ___II·1-- -- 130 - ---- - - ~~-

:3,300___ _ _ 1--------- _

---'------

___ ~--r

8050

1----

-1-~- ------

--I --

-- ---

----

=~=~TI

~:;u:-:.=-~__ ~_~_~~~ -~=- -~:~~~ __ -__ -i,ooo -- __ ._~._~1~ -_-~-:::~~ 1-~;~~-\-:';3-~1-~--0--~- --.Lead_ IS __ 30 18,'1 __ __ _ 1 to 5, _

II MllI\J:3I\es_e__________ _ 1,70_0_ _ _ 120 36 to 1,470VOLA TILE ORGANICS~ ------,-'0.:=-=---,---------- _

II_A_cct.one f- 610

Be_nzene. ___ __ __ __ ___ 5

}, 1:I>ic1Jl~roeth~e.___ ...190J~I-Dichloroet1Je!,e 7 + _"is-.!,2-Dichloroethen~ 70

!~::~;~~-)'~-~;:~~: 1:{90 ---t----IMetltylJsobutyl ketone .__ 160 _

1".oI.uen,,______ _1,000 _Trichloroethene 5-- - - - - - -- - -- ---------

1,1,1-TricN<)f'oethane 2.QO1,1,2-Trichloroethane 3.I,I,2~Trichl0r<>trifluoroetl1llI\e _ .59,000I~MI~VOL1TlJ-Ii ORG,.ji\'Ic;S _BJ~(2-eth)'LhexY})Jlhthalate__j L __EXPLOSIVES

--------- - -.,' "._---------

-'_J,5~I!inilr"_blJnzeneJ"[Nll)___1,8

},3-Dinitr.olJenzene(DN_BL J2,4-DinitrotolueneJ24QNT) 52,6-Dinitrotoluene (2~{)1'lD_ _ 52,4,6:T.rinitrotoluene (TNT) 2HMX 400----- -- .. - -------- -- -

J'.Iitrobe,!zene(l'lBl_ _ _ _ 3ARDX 2



discharge is in sufficient quantities, and the NOAEL concentrations are exceeded after dilutional effects,

ecological risks may begin to be manifested and the threatened darter population be stressed.

Table 8-4 indicates that PROs exceed NOAEL concentrations for barium, iron, and manganese, but so do

natural background concentrations in surface water at IAAAP. PROs also exceed NOAEL concentrations

for I, I, I-trichloroethane and bis(2-ethylhexyl)phthalate, but not for any explosives for which we developed

NOAELs. As is the case for soils, the PROs for explosives are the principal driver to remediation of most

contaminated groundwater, and those cleanup objectives are sufficient to protect darters. The use of

NOAEL values assures conservative estimates.

8.2 Basewide Receptors

Most birds and large mammals are not limited to individual watersheds at IAAAP and will cross drainage

boundaries for feeding, breeding or general migration purposes. Hence a watershed-based ERA such as

presented herein may not address risk for wide-ranging species. Because of its listing as a federal threatened

species and a management objective at the national level, the viability of the bald eagle population was

included as an assessment endpoint in the ERAA. Bald eagle are principally fish eaters and our watershed

based risk assessment presented in Chapters 4 through 7 assumed that the individual eagle fed in a specific

watershed five per cent of the time it was eating (i.e. exposure modification rate, EMR ; 0.05). Other

raptors, while not necessarily a federal or state listed threatened or endangered species, may be exposed at

higher rates at IAAAP due to differences in feeding patterns.

To evaluate the potential for risk to a wide-ranging predatory species that feeds solely on the IAAAP, we

estimated risk to red-tailed hawk (Buteo jamaicensis). The red-tailed hawk is the most common Buteo sp.

in the US and it does occur on the lAAAP property. Nesting primarily in woodlands, red-tailed hawks feed

in open country on a wide variety of small to medium sized prey. Hunting generally occurs near woodland

edges. Red-tails are generally opportunistic and will feed on whatever species are most abundant. Small

mammals, including mice, shrews, voles, squirrels and rabbits are important prey items, but red-tails will also

take pheasants and other birds, lizards and snakes, and large insects. At the latitude of IAAAP, red-tailed

hawks may be year-round residents. Home range size is large, and may vary from a few hundred acres to

a few square miles (USEPA 1993).



To estimate a conservative level of risk to this raptor, the following assumptions have been applied:

• Soil COEC concentrations in Brush Creek watershed represent exposure point

concentrations. COEC concentrations in Brush Creek are generally the highest

among the four watersheds.

• Only bioaccumulating COECs represent a significant risk to predatory biota.

• EMR= 1.0

• NOAEL endpoints scaled based upon body weight from test organisms taken from

Sample, et al. 1996

Table 8-5 contains HQ estimates based upon this approach. HQs exceeding unity represent potential effects

greater than the NOAEL, and are possible for dibenzofuran, DDT metabolites, and chlordane. None of these

contaminants are due to munitions manufacturing and all are based on very few measurements relative to the

analyses for explosives and metals. While they may be due to historic application of agrochemicals by

farmers leasing lands on the IAAAP, DDT and its metabolites, and chlordane are no longer licensed for

agricultural use. The chlordane exposure point concentration is derived from a single measurement event

from the Brush Creek watershed at the Pesticide Pit in November, 1992, and is not representative of general

basewide conditions. For example, the highest level of chlordane found in soil samples collected near

chlordane-contaminated NPL sites has been 57,000 Ilg/kg (ATSDR 1989). Dibenzofurans have never had

any commercial use other than pure research. Dibenzofurans are produced in small amounts as undesirable

by-products of certain manufacturing and incineration operations.

Table 8-5. Potential Risk to llJ!kQ Species

COEC COEC in Soils (U2!k2) Dose (m2/k2/d) NOAEL (m2lk2/d\ HQ

Mercurv 446 0.011 0.45 2.E-02

Dibenzofuran 119 0.0002 1.2E-05 2.E+OI

4,4'-DDD 794 0.021 0.003 7.E+00

4,4'-DDE 2007 0.047 0.003 2.E+01

4,4'-DDT 267 0.002 0.003 6.E-Ol

aloha-Chlordane 880000 2.16 0.59 4.E+00

Igamma-Chlordane 640000 1.57 0.59 3.E+00

PCB 1260 2398 0.005 0.18 3.E-02



The uncertainty of the HQs for these contaminants is high. Additionally the HQs are likely overestimates

due to the small size ofthe data base, the use of the most contaminated watershed (Brush Creek) to represent

the total feeding area of red-tailed hawks, and the use ofNOAEL criteria for hazard estimation.

8.3 Conclusions

We have completed an ERAA intended to evaluate past and ongoing operations of the IAAAP. Assessment

endpoints have included environmental health indicators at both the individual and community levels, for

aquatic and terrestrial ecosystems in four watersheds. While there are minor indications that past

contamination presents stress to the selected indicators, IAAAP operations, by and large, are not significantly

impacting environmental resources. Soil and groundwater PROs are likely protective ofecological receptors

in most instances, but we have identified circumstances where those PROs may not be sufficiently protective,

particularly for certain metals and biomagnifying COECs.

Spring and Brush Creeks are exposed to concentrations of some metals that may be affecting orangethroat

darters. However, we found good numbers of this threatened species in these streams during our field

investigations, and individuals that we examined did not show signs of stress as indicated by DELTs

(deformities, eroded fins, lesions, or tumors).

The benthic community of IAAAP streams was appraised as being impaired to slightly impaired. Benthos

in the streams are generally more diverse and balanced than streams in completely agricultural watersheds

ofeastern Iowa. Aquatic invertebrates are known to become moderately tolerant of metals, and the benthos

measurement endpoints may not reflect risks from metals seen in the darter viability risk assessment.

Risks to terrestrial ecosystems were assessed using both measurement and modeling procedures. The forest

community structure endpoint shows the adverse effects of ongoing land use and management practices.

Reduced forest tract size is likely impacting forest quality. Forest ecology principals demonstrate that

reducing tract size, while increasing gaps or "edge" habitats, alters microclimate in the forest that affects

species diversity, dominance and abundance. Inside the reduced-sized forest tract, wind speeds increase,

mean temperature increases, humidities decrease, and light penetration increases. All these factors reduce

forest quality, and at IAAAP, are more likely affecting forest community structure than industrial

contamination.



The viability ofsmall mammal populations does not appear to be at significant risk in any watershed. Hazard

quotients (HQ) exceeding unity are limited to silver in soils near the wastewater treatment plant (WWTP)

on Brush Creek. Dibenzofuran may present a slight hazard to small mammal populations in the Brush Creek

watershed, but additional analytical data would be needed to confirm the significance ofthis COEC there.

Bald eagle populations do not appear to be at risk in the lAAAP.



Chapter 9

REFERENCES

Agency for Toxic Substances and Disease Registry. December, 1989. Chlordane Public Health Statement.

URL: http://atsdr1.atsdr.cdc.gov:8080/ToxProfiles/phs8906.htmI.

Baes, C. F., R. D. Sharp, A. L. Sjoreen, and R. W. Shor. 1984. A Review and Analysis of Parameters for

Assessing Environmentally Released Radionuclides through Agriculture. ORNL-5785. Oak Ridge

National Laboratory, Oak Ridge, TN.

Beyer, W. N., E. E. Connor, and S. Gerould. 1994. Estimates of Soil Ingestion by Wildlife. J. Wild!.

Manage. 58(2):375-382.

Bunyan, J., A.T. Diplock, M.A. Cawthorne and J. Green. 1968. Vitamin E and stress. 8. Nutritional effects

of dietary stress with silver in vitamin E-deficient chicks and rats. Br. J. Nutr. 22(2): 165-182.

Connell, D. W. 1990. Bioaccumulation ofXenobiotic Compounds. CRC Press, Boca Raton, FL.

Cummins, K. W. and M. A. Wilzbach. 1985. Field Procedures for Analysis of Functional Feeding Groups

of Stream Macroinvertebrates. Contribution 1611, Appalachina Environmental Laboratory, Univ.

Maryland, Frostburg, MD.

Dierenfeld, E. A., M. P. Fitzpatrick, T. C. Douglas, and S. A. Dennison. 1996. Mineral Concentrations in

Whole Mice and Rats Used as Food. Zoo Biology 15: 83-88.

Diplock, A. T., J. Green, J. Bunyan, D. McHale and I.R. Muthy. 1967. Vitamin E and stress. 3. The

metabolism of D-alpha-tocopherol in the rat under dietary stress with silver. Br. J. Nutr. 21 (I):

115-125.



Eisler, R. 1987. Polycyclic Aromatic Hydrocarbon Hazards to Fish, Wildlife, and Invertebrates: A Synoptic

Review. U.S. Fish and Wildlife Service. Biological Report 85(1.11).

Furchner, lE., C.R. Richmond and G.A. Drake. 1968. Comparative metabolism of radionuclides in

mammals - IV. Retention of silver - 110m in the mouse, rat, monkey, and dog. Health Phys. 15:

505-514.

Garlen, C. T. and J. R. Trabalka. 1983. Evaluation of Models for Predicting Terrestrial Food Chain

Behavior ofXenobiotics. Environmental Science and Technology 17:570-575.

Hana Environmental Services, Inc. 1997a. Supplemental Groundwater Remedial Investigation Report, Iowa

Army Ammunition Plant, Middletown, Iowa. Prepared for the Omaha District, U.S. Army Corps

of Engineers, Omaha, Nebraska by Harza, Chicago, Illinois.

Harza Environmental Services, Inc. 1997b. Work and Quality Assurance Plan for the Ecological Risk

Assessment Addendum, Iowa Army Ammunition Plant, Middletown, Iowa. Prepared for the Omaha

District, U.S. Army Corps of Engineers, Omaha, Nebraska by Harza, Chicago, Illinois.

Horton, D., el al. June, 1996. An Assessment of the Natural Habitats and Biota of the Iowa Army

Ammunition Plant, Middletown, Iowa. University ofIowa, Iowa City, Iowa.

Hilsenhoff, W.L., 1988. Rapid Field Assessment of Organic Pollution with a Family-Level Biotic Index,

American Benthological Society, Journal 7(1): 65-68.

Iowa Department ofNatural Resources Environmental Protection Division, Water Resources Section. 1994.

Habitat Evaluation Procedures for Wadeable Streams ofIowa. Des Monies, IA.

Jackson, H.H.T. 1961. Mammals of Wisconsin. University of Wisconsin Press, Madison, WI.

JAYCOR. 1996. Remedial InvestigationlRisk Assessment, Iowa Army Ammunition Plant, Middletown

(Revised Draft Final), Volumes 1,2, and 3 of II, 21 May 1996.

JAYCOR and ICAIR Life Systems. 1996. Remedial Investigation/Risk Assessment, Iowa Army

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Fina/) 8-2 March 20, 1998

Page 9-2

Ammunition Plant, Middletown (Revised Draft Final), Volume II of II, 21 May 1996.

Mackay, D. 1982. Correlation of Bioconcentration Factors. Environmental Science and Technology

16:274-278.

Maxwell, C.J., D.M. Opresko. 1996. Ecological Criteria Document for Octahydro-I,3,5,7-Tetranitro

1,3,5,7-Tetrazocine (HMX). Oak Ridge National Laboratory, Oak Ridge, Tennessee.

Olcott, C.T. 1950. Experimental argyrosis. V. Hypertrophy of the left ventricule of the heart in rats

ingesting silver salts. Arch. Pathol. 49: 138-149.

Peakall, D. B. 1996. Dieldrin and Other Cyclodiene Pesticides in Wildlife. Chapter 3 in Enyironmental

Contaminants in Wildlife.lntell'retjng Tissue Concentrations. Edited by W. N. Beyer, G. H. Heinz,

and A. W. Redmon-Norwood. Lewis Publishers, New York.

Plafkin, 1. L., T. Barbour, K.D. Porter, S.K. Gross, and R.M. Hughes. 1989. Rapid Bioassessment Protocols

for Use in Streams and Rivers. Benthic Macroinvertebrates and Fish. EPA/444/4-89-001.

Reddy, T.V., F.B. Daniel, M. Robinson, et al. 1994. Subchronic Toxicity Studies on 1,3,5-Trinitrobenzene,

1,3-Dinitrobenzene, and Tetryl in Rats: Subchronic Toxicity Evaluation of 1,3,5-Trinitrobenzene

in Fischer 344 Rats. U.S. Environmental Protection Agency, Environmental Monitoring Systems

Laboratory, Cincinnati, OH; AD-A283 663/3/HDM, National Technical Information Service,

Springfield, VA.

Sawicka-Kapusta, K., A. Gorecki, and R. Lange. 1987. Heavy Metals in Rodents from Polluted Forests in

Southern Poland. Ekologia Polska 35(2):345-354.

Sample, B.E., D.M. Opresko, G.W. Suter II. 1996. Toxicological Benchmarks for Wildlife: 1996 Revision.

Report No. ES/ER/TM-861R3. Risk Assessment Program, Oak Ridge National Laboratory, Oak

Ridge, Tennessee.

Schneider, 1. F., S.D. Zellmer, N.A. Tomczyk, J.R. Rastorfer, D. Chen, and W.L. Banwart. 1995. Uptake

ofExplosives from Contaminated Soil by Existing Vegetation at the Iowa Army Ammunition Plant,

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Final) 8-3

Msrch 20, 1998Psge 9-3

Report No. SFIM-AEC-ET-CR-95013. Argonne National Laboratory, Argonne, IL.

Schwartz, C.W. and E.R. Schwartz. 1981. The Wild Mammals of Missouri (Revised Edition). Published

by University of Missouri Press, Columbia, Missouri.

Shah, B. G. and B. Belonje. 1991. Marginal or Excess Dietary Iron and Rat Tissue Trace Element Levels.

Trace Elements in Medicine 8(3): 143-148.

Smith, P. 1979. The Fishes of Illinois. Published by Univ. Illinois Press, Chicago, IL.

SRC (Syracuse Research Corporation). 1985. Reference Values for Risk Assessment. Prepared for

USEPA, Environmental Criteria and Assessment Office, Cincinnati, Ohio, by SRC, Syracuse, NY.

Suter II, G. W. and C.L. Tsao. 1996. Toxilogical Benchmarks for Screening Potential Contaminants of

Concern for Effects on Aquatic Biota: 1996 Revision. Risk Assessment Program, Oak Ridge,

Tennessee.

Talmage, S.S. and D.M. Opresko. 1996a. Ecological Criteria Document for 2,4,6-Trinitrotoluene. Oak

Ridge National Laboratory, Oak Ridge, Tennessee.

Talmage, S.S. and D.M. Opresko. 1996b. Ecological Criteria Document for 1,3,5-Trinitrobenzene. Oak

Ridge National Laboratory, Oak Ridge, Tennessee.

Talmage, S.S. and D.M. Opresko. 1996c. Ecological Criteria Document for 1,3-Dinitrobenzene. Oak Ridge

National Laboratory, Oak Ridge, Tennessee.

Talmage, S.S., D.M. Opresko, and F.M. Cretella. 1996d. Ecological Criteria Document for Hexahydro

1,3,5-Trinitro-I,3,5-Triazine (RDX). Oak Ridge National Laboratory, Oak Ridge, Tennessee.

Talmage, S.S., D.M. Opresko, and C.J.E. Welsh. I996e. Ecological Criteria Document for N-Methyl

N,2,4,6-Tetranitroaniline (Tetryl). Oak Ridge National Laboratory, Oak Ridge, Tennessee.

Thompson, D.R. 1996. Mercury m Birds and Terrestrial Mammals. Chapter 14 m Environmental



Contaminants in Wildlife. Inte'l'retinll Tissue Concentrations. Edited by W. N. Beyer, G. H. Heinz,

and A. W. Redmon-Norwood. Lewis Publishers, New York.

Travis, C. C. and A. D. Arms. 1988. Bioconcentration of Organics in Beef, Milk, and Vegetation.

Environmental Science and Technology 22(3):271-274.

U.S. Army Corps of Engineers (USACE). June 1996. Risk Assessment Handbook Volume II:

Environmental Evaluation, Engineers Manual EM 200-1-4. Washington, D.C.

U.S. Environmental Protection Agency (USEPA). 1993. Wildlife Exposure Factors Handbook, Volume I.

EPA/6001R-93/187a. U.S. Environmental Protection Agency, Washington, DC.

U.S. Environmental Protection Agency. 1995. Great Lakes Water Quality Initiative Methodology for

Development of Bioaccumulation Factors. Final Rule. Federal Register 60 (56). March 23,1995.

U.S. Environmental Protection Agency. 1996. ECO Update. Publication 9345.0-12FSI EPA 540/F-95/038.

Washington, D.C.

U.S. Environmental Protection Agency. USEPA Integrated Risk Information System (IRIS) Web Prototype.

1997. URL: http://www.epa.gov/docs/ngispgm3/iris/index.html.

U.S. Environmental Protection Agency. 1997. Ecological Risk Assessment Guidance for Superfund,

Process for Designing and Conducting Ecological Risk Assessments. EPA/540/R-97/006.

Washington, D.C.

Veith, G. D., D. L. DeFoe, and B. V. Bergstedt. 1979. Measuring and Estimating the Bioconcentration

Factor of Chemicals in Fish. J. Fish. Res. Board Can. 36: 1040-1048.

Wagner, P.A., W.G. Hoeskstra and H.E. Ganther. 1975. Alleviation of Silver Toxicity by Selenite in the

Rat in Relation to Tissue Glutathione Peroxidase. Proc. Soc. Exp. BioI. Med. 148(4): 1106-1 I 10.

Water Environment Research Federation (WERF). 1996. Aquatic Ecological Risk Estimation: A Multi

Tiered Approach. Project 91-AER-1. Alexandria, VA.



Weiner, 1. G. and D. 1. Spry. 1996. Toxicological Significance ofMercury in Freshwater Fish. Chapter 13

in Environmental Contaminants in Wildlife Interpreting Tissue Concentrations. Edited by W. N.

Beyer, G. H. Heinz and A. W. Redmon-Norwood. Lewis Publishers, New York, N.Y.

Will, M. E. and G. W. Suter II. 1995. Toxicological Benchmarks for Screening Potential Contaminants of

Concern for Effects on Terrestrial Plants: 1995 Revision. ES/ER/TM-85/R2. Oak Ridge National

Laboratory, Oak Ridge, Tennessee.

Wlostowski, T., W. Chetnicki, W. Gierlachowska-Baldyga, and B. Chycak. 1988. Zinc, Iron, Copper,

Manganese, Calcium and Magnesium Supply Status ofFree-Living Bank Voles. Acta Theriologica

33(41): 555-573.

Wren, C. D., S. Harris, and N. Harttrup. 1995. Ecotoxicology of Mercury and Cadmium. Chapter 17 in

Handbook of Ecotoxicology. Edited by D. J. Hoffman, B. A. Rattner, G. A. Burton, and J. Cairns.

Lewis Publishers, New York.

lows Armv Ammunition PlantEcological Risk Assessment Addendum (Draft Final) 8-6


APPENDIXA

SCREENING AND PRELIMINARYIDENTIFICATION OF COECs

APPENDIX A

Screening and Preliminary Identification of COECs

The data available for review and identification ofchemicals ofecological concern (COECs) included those

from the RIIFS (JAYCOR 1996), forwarded to Harza by the lAAAP. The database files were in the format

supported by Microsoft Access (version 97) and were named SoilsJs.mdb (19,136 kB), WaterJs.mdb

(26,080 kB) and Ip_data.mdb (28,800 kB). COECs were identified on a watershed basis, by first designating

the basin for each ofJAYCOR's soil, sediment or water sampling locations. This being done, we screened

the database comparing each watershed contaminant to toxicological or statistical criteria.

Screening of the Data

Groundwater and soils deeper than 24 inches generally do not present a significant exposure pathway to

ecological receptors. Groundwater on the IAAAP does enter streams and then become an exposure point,

but such contaminants were assumed to be implicitly represented in the large surface water contaminant

database for the site.

Non-detects and probable lab contaminants were eliminated from consideration. Essential nutrients

generally do not present a hazard and were eliminated from consideration if levels were less than those

known to cause problems; e.g., ammonia nitrogen less than water quality standards. Radiological

contaminants were eliminated due to their low levels.

Preliminary Identification of COECs

Toxicological benchmarks for further screening the databases are shown on the attached pages. We used

Iowa chronic water quality standards, USEPA Region II Biological and Technical Advisory Group (BTAG)

criteria, USEPA (1996) and, for explosive compounds, USACE (1996) as benchmarks. Contaminants

exceeding these toxicological benchmarks were retained as preliminary COECs for the watershed.

Water and soil data sets were much larger than sediment. To assure that the COECs represented general risks

and not just single points, water and soil contaminants which exceeded screening levels in 5% or more of

records were retained as COECs. This eliminated contaminants with limited distribution. However, any


March 79, 7998PageA·1

record of a chemical known to biomagnify in food chains was retained as a COEC. Chemical data passing

through this elimination algorithm were retained as COECs.

Iowa Army Ammunition Plant March 19, 1998Ecological Risk Assessment Addendum (Draft Fina/} Page A·2

Screening Criteria

Chemical Soil (ug/kg) Water (ug/L) Sediments (ug/kg)Flora Fauna 10waCWQS Ecotox BTAG Ecotox BTAG

INORGANICSAluminum 50,000 3,290 25Antimony 480 30 150,000Arsenic 328,000 200 8,200Barium 440,000 3.90 10,000Beryllium 20 5.1 5.3Cadmium 2,500 15 1,200CalciumChromium 20 7.5 40 81,000Cobalt 100 200 3Copper 15,000 35 34,000

Iron 3,260,000 12,000 1,000Lead 2,000 10 30 47,000MagnesiumManganese 330,000 80Mercury 58 0.05 150

Nickel 2,000 650 21,000

Nitrite, NitratePotassiumSelenium 1,800 125Silver 0.0098 8.5 1,000

SodiumSulfateThallium 1 40

Vanadium 500 58,000 19

Zinc 10,000 450 150,000

VOLATILES1,1,1-Trichloroethane 62 170

1,1,2,2-Tetrachloroethane 420 940

1,1,2-Trichloroethane1,1-Dichloroethane 471,1-Dichloroethene1,2-Dichloroethane1,2-Dichloroethene1,3-DimethylbenzeneAcetoneBenzene 100 46 57

Bromodichloromethane 450 11,000

Carbon disulfide 2

Carbon tetrachloride 300 35,200

Chloroform 300 1,240

ChloromethaneDibromochloromethane 11,000

Ethylbenzene 100 290 3,600

Methylene chloride 300 11,000

Methylethyl ketone 322,000

Methyl-n-butyl ketoneMethylisobutyl ketone 100,000 460,000

Tetrachloroethene 300 840 57

Toluene 100 50 67Trichloroethene 300 80 21,900Trichlorofluoromethane 100 11,000 0.04Vinyl chlorideXylenes 100 1.8 25

criteria.wb2 19-Mar-98

Screening Criteria

Chemical Soil (ug/kg) Water (ug/L) Sediments (ug/kg)Flora Fauna 10waCWQS Ecotox BTAG Ecotox BTAG

SEMIVOLATILES1,2-Dichlorobenzene 100 14 3401,4-Dichlorobenzene 100 15 3502,4,5-Trichlorophenoxyacetic acid2,4-Dichlorophenoxyacetic acid3,5-Dintroaniline4-MethylphenolBenzyl alcohol 460,000 57CarbazoleDibenzofuran 540Isophorone 117,000N-NitrosodiphenylaminePhenol 100 50 420

PAHsAcenaphthene 20 23 16Acenaphthylene 100 44Anthracene 100 0.1 85.3Benzo(a)anthracene 100 6.3 261Benzo(a)pyrene 100 0.014 430Benzo(b)fluoranthene 100 3,200Benzo(g,h,i)perylene 100 670Benzo(k)fluoranthene 1002-ChloronaphthaleneChrysene 100 384Dibenz(a,h)anthracene 100 63.4Fluoranthene 100 8.1 600Fluorene 100 3.9 19Indeno(1,2,3-c,d)pyrene 100 6002-Methylnaphthalene 70Naphthalene 100 160Phenanthrene 100 850Pyrene 100 660Total PAHs 0.03

PHTHALATESbis(2-Ethylhexyl) phthalate 32 1,300Butylbenzyl phthalate 19 11,000Di-n-butyl phthalate 33 11,000Diethyl phthalate 220 630Dimethyl phthalate 71

PESTICIDES/PCBS4,4'-000 100 0.001 0.6 164,4'-DDE 100 0.001 1,050 2.24,4'-DDT 100 0.001 1.6Aldrin 100 3alpha-Chlordanebeta-Endosulfan 0.15 5.4Chlordane 100 0.004delta-BenzenehexachlorideDieldrin 100 0.0019 52Endrin 100 0.0023 20gamma-Chlordane 0.0069


23

3.7

Sediments (ug/kg)Ecotox BTAG

0.0038

0.014

Water (ug/L)Iowa CWQS Ecotox BTAG

0.00380.330.25

100100

100

Screening Criteria

Soil (ug/kg)Flora Fauna

Chemical

HeptachlorHeptachlor epoxideLindanePCB 1254PCB 1260Total PCB

EXPLOSIVES1,3,5-Trinitrobenzene1,3-Dinitrobenzene2,4,6-TNT2,4-DNT2,6-DNTHMXNitrobenzeneRDXTetryl

230

27,000


Brush Creek Soils Screening Data

Maximum Values for Chemicals above DL In one or more samples.

CLASS DESCRIPTION Max VALUE SCREENING NOTES Findingmglkg

ANIONS Nitrite, nitrate wnonsp 38 Nutrient/essential elementSulfate 1400 Nutrient/essential element

EXPLOSIVES 1,3,5-Trinitrobenzene 23000 nd1,3-Dinitrobenzene 2.77 OK (>95% < DL)2,4,6-Trinitrotoluene I a 100000 nd2,4-Dinitrololuene 210 OK (>95% < DL)2,6-Dinitrotoluene 3.3 OK (>95% < DL)Cyclotetramethylenetetran 6700 ndNitrobenzene / Essence of 68 OK (>95% < DL)RDX I Cyclonile I Hexahyd 7200 ndTetryll N-Methyl-N,2,4,6 8300 OK (>95% < DL)

RAD Actinium 228 1.9 EliminatedAlpha gross 8.78 EliminatedBeta gross 13.2 EliminatedBismuth 214 1.51 EliminatedCesium 137 0.42 EliminatedLead 212 1.5 EliminatedLead 214 1.3 EliminatedPotassium 40 17 EliminatedRadium 226 5.6 EliminatedThallium 208 0.73 Eliminated

TAL_METAL Aluminum 21800 5% > 15,900 COEC (Flora)Antimony 2820 OK (95% <= 19.6)Arsenic 79 OK (Max < Threshold)Barium 14000 OK (Max < Threshold)Beryllium 100 OK (95% <= 2.24)Cadmium 60.8 OK (Max < Threshold)Calcium 350000 Nutrient/essential elementChromium 1530 5% > 130 COEC (Flora & Fauna)Cobalt 58.6 OK (Max < Threshold)Copper 12000 OK (Max < Threshold)Iron 94000 5% > 26,200 COEC (Fauna)Lead 13000 5% > 885 COEC (Fauna)Magnesium 29700 Nutrient/essential elementManganese 7700 OK (Max < Threshold)Mercury 2000 Max > Threshold * COEC (Fauna)Nickel 193 OK (Max < Threshold)Potassium 3060 Nutrient/essential elementSelenium 3.29 OK (Max < Threshold)Silver 260 5% > 2.58 COEC (Flora)Sodium 1730 Nutrient/essential elementThallium 67.3 5% > 34.3 COEC (Flora)Vanadium 302 OK (Max < Threshold)Zinc 5600 OK (Max < Threshold)

TCL_BNA 1,4-Dichlorobenzene 10 OK (>95% < DL)2-Methylnaphthalene 200 OK (>95% < DL)Acenaphthene 9 OK (Max < Threshold)Acenaphthylene 0.2 OK (Max < Threshold)Anthracene 20 OK (Max < Threshold)Benzo[a]anthracene 80 OK (Max < Threshold)Benzo[a)pyrene 100 OK (95% <= 5)Benzo[b]fluoranthene /3, 100 OK (95% <= 5)Benzo[def]phenanthrene / 100 ndBenzo[ghi)perylene 21 OK (Max < Threshold)Benzo[k]fluoranthene 30 OK (Max < Threshold)Bis(2-ethylhexyl) phthala 2.1 ndButylbenzyl phthalate 10 OK (>95% < DL)Carbazole / 9HwCarbazoie 20 nd

Brush Creek Soils Page 1

Brush Creek Salls Screening Data

CLASS DESCRIPTION Max VALUE SCREENING NOTES FindingChrysene 100 OK (95% <=3)Di-n-butyl phthalate 6.2 ndDibenz[ahjanthracene /1, 5 OK (>95% < Dl)Dibenzofuran 30 ndFluoranthene 200 OK (95% <= 5)Fluorene I 9H-FJuorene 10 OK (Max < Threshold)Indeno[1,2,3-C,D]pyrene 30 OK (Max < Threshold)Naphthalene! Tar camphor 20 OK (Max < Threshold)Phenanthrene 60 OK (Max < Threshold)Phenol! Carbolic acid! 1.3 OK (Max < Threshold)

TCl_PEST 2,2-Bis(p-chlorophenyl)-1 21000 ndalpha-Chlordane 880 ndDieldrin 0.0169 OK (Max < Threshold)Endrin 1400 OK (>95% < Dl)gamma·Chlordane 640 ndHeptachlor /1H-1 ,4,5,6,7 290 OK (>95% < Dl)PCB 1260 100 = "Total PCB" Threshold' COEC (Fauna)ppDDD /1,1-Dichloro-2,2- 1200 > "Total PCB" Threshold' COEC (Fauna)

TCl_VOA Benzene 0.0079 OK (Max < Threshold)Toluene 0.8 OK (Max < Threshold)

NOTE: • = Biomagnifier

Brush Creek Soils Page 2

Brush Creek Sediment Screening Data


CLASS DESCRIPTION ax VALUE SCREENING NOTES Findingmglkg

ANIONS Nitrite, nitrate • nonsp 2.12 NutrienUessential elementSulfate 190 NutrienUessential element

EXPLOSIVE 1,3,5--Trinitrobenzene 100 nd1,3·Dinitrobenzene 2.37 OK (>95% < DL)2,4,6-Trinitrotoluene I a 270000 nd2,4-Dinitrotoluene 2.86 OK (>95% < DL)2,6-Dinitrotoluene 5.79 OK (>95% < DL)Cyclotetramethylenetetran 28000 ndRDX / Cyclonrte / Hexahyd 100000 nd

TAL_METAL Aluminum 210000 ndAntimony 47.2 OK (Max < Threshold)Arsenic 24 OK (Max < Threshold)

Barium 24000 ndBeryllium 2.62 ndCadmium 69.4 OK (Max < Threshold)

Calcium 85000 Nutrient/essential elementChromium 1360 OK (Max < Threshold)

Cobart 79.8 ndCopper 1810 OK (Max < Threshold)

Iron 86100 ndLead 5630 OK (Max < Threshold)Magnesium 40900 Nutrient/essential elementManganese 8640 ndMercury 3 OK (Max < Threshold)

Nickel 284 OK (Max < Threshold)

Potassium 3810 Nutrient/essential elementSelenium 2.98 nd

Silver 24 OK (Max < Threshold)

Sodium 820 NutrjenUessential elementThallium 31.8 nd

Vanadium 64.9 nd

Zinc 7650 OK (Max < Threshold)

TCL_BNA 2-Chloronaphthalene 0.13 OK (>95% < DL)

2-Methylnaphthalene 4.3 OK (Max < Threshold)Acenaphthene 0.36 OK (Max < Threshold)

Anthracene 0.69 OK (Max < Threshold)

Benzo[a]anthracene 0.49 OK (Max < Threshold)

Benzo[deijphenanthrene / 1.2 ndBenzo[k)fluoranthene 0.31 OK (>95% < DL)

Bis(2-ethylhexyl) phlhala 7.7 OK (Max < Threshold)

Chrysene 0.62 OK (Max < Threshold)

Di-n-butyl phthalate 1.1 OK (Max < Threshold)

Dibenzofuran 0.19 OK (Max < Threshold)

Fluoranthene 0.66 OK (Max < Threshold)

Fluorene 19H-Fluorene 0.35 OK (Max < Threshold)

Naphthalene / Tar camphor 1.5 OK (Max < Threshold)

Phenanthrene 4.4 OK (Max < Threshold)

TCL_PEST 2,2-Bis(p-chlorophenyl)-1 0.0153 OK (>95% < DL)

Dieldrin 0.0197 OK (Max < Threshold)

PCB 1254 3.3 OK? (I PCB's < 100)

PCB 1260 3.6 OK? (I PCB's < 100)

TCL_VOA Tetrachloroethane /1 ,1,2 2 OK (Max < Threshold)

Toluene 0.0065 OK (Max < Threshold)

NOTE: No COEC's Identified

Brush Creek Sediments Page 1

Brush Creek Surface Water Screening Data

Maximum Values for Chemicals above DL in one or more samples.

CLASS DESCRIPTION Max VALUE SCREENING NOTES Findingug/L

ANIONS Nitrite, nitrate - nonsp 5300 utrient/essential elementSulfate 1500000 utrient/essential element

EXPLOSIVES 1,3,5-Trinitrobenzene 880 OK (95%<=80)1,3-Dinitrobenzene 2.12 OK (Max < Threshold)2,4,6-Trinitrotoluene I a 8000 OK (95%<=91.1)2,4-Dinitrotoluene 81 OK (Max < Threshold)2,6-Dinitrotoluene 13.5 OK (Max < Threshold)Cyclotetramethylenetetran 740 ndNitrobenzene I Essence of 7.65 OK (Max < Threshold)RDX I Cyclonite I Hexahyd 5400 ndTetryll N-Methyl-N,2,4,6 8.83 nd

TAL_METAL Aluminum 740000 5% > 10,900 COECArsenic 44.9 OK (Max < Threshold)Barium 996 5% > 251 COECBeryllium 56 OK (95%<=1.44)Cadmium 19.1 OK (>95% < DL)Calcium 93700 utrient/essential elementChromium 1600 5% > 84 COECCobalt 240 OK (>95% < DL)Copper 320 5% > 110 COECIron 2500000 5% > 10,900 COECLead 660 5% > 140 COECMagnesium 35600 utrient/essential elementManganese 19000 5% > 453 COECMercury 5.9 Max> Threshold' COECNickel 1900 OK (>95% < DL)Potassium 1100000 utrient/essential elementSelenium 8.84 OK (Max < Threshold)Silver 2130 5% > 25.1 COECSodium 3800000 utrient/essential elementVanadium 31.3 OK (95%<=14.7)Zinc 1580 5% > 841 COEC

TCL_BNA Bis(2-ethylhexyl) phthala 16 OK (Max < Threshold)Diethyl phthalate 39 OK (Max < Threshold)

TCL_VOA Bromodichloromethane 6.9 OK (Max < Threshold)Carbon disulfide 6.8 OK (95%<=0.91)Carbon tetrachloride 1.7 OK (Max < Threshold)Chloroform 30 OK (Max < Threshold)Chloromethane 8.7 ndDibromochloromethane I C 0.9 OK (Max < Threshold)Methylene chloride I Dich 4.2 OK (Max < Threshold)Trichloroethylene /Trichl 0.581 OK (Max < Threshold)

, Bio-Magnifier

Brush Creek Water Page 1

Long Creek Soils Screening Data

Maximum Values for Chemicals above OLin one or more samples.

ANIONS Nrtrite, nitrate - nonspSulfate

EXPLOSIVES 1,3,5-Trinitrobenzene1,3-Dinitrobenzene2,4,6-Trinitrotoluene I a2,4-Dinl1rotoluene2,6-DinitrotolueneCyclotetramethylenetetranNitrobenzene I Essence ofRDX I Cyclonite I HexahydTetryll N-Methyl-N,2,4,6

RAD Actinium 228Alpha grossBeta grossBismuth 212Bismuth 214Cesium 137Lead 212Lead 214Potassium 40Radium 226Thallium 208Thorium 234

TAL_METAL AluminumAntimonyArsenicBariumBerylliumCadmiumCalciumChromiumCobartCopperIronLeadMagnesiumManganeseMercuryNickelPotassiumSeleniumSilverSodiumThalliumVanadiumZinc

TCL_BNA Benzo[ajanthraceneBenzo[def]phenanthrene IBenzo[ghijperyleneBenzo[k)fluorantheneBis(2-ethylhexyl) phthalaChryseneDi-n-bulyl phthalateFluoranthenePhenanthrenePhenol I Carbolic acid I

TCL_PEST 2,2-Bis(p-chlorophenyl)-1Aldrin

CLASS DESCRIPTION Max VALUE SCREENING NOTES Findingmg/kg

23 Nutrient/essential element560 Nutrient/essential element

21 nd6.6 OK (>95% < DL)

25000 nd13.2 nd

1.3 OK (>95% < DL)13000 nd

3.47 OK (>95% < DL)75000 nd14000 OK (>95% < DL)

1.8 Eliminated23.4 Eliminated45.9 Eliminated

1.1 Eliminated1.52 Eliminated0.44 Eliminated

1.5 Eliminated1.5 Eiiminated19 Eliminated12 Eliminated

0.72 Eliminated38 Eliminated

41400 5% > 18,300 COEC (Flora)4400 OK (95% <= 12.4)

99 OK (Max < Threshold)1240 OK (Max < Threshold)

5.6 OK (Max < Threshold)801 OK (Max < Threshold)

270000 Nutrient/essential element2800 5% > 92.7 COEC (Flora & Fauna)31.6 OK (Max < Threshold)

47000 OK (95% <= 577)170000 5% > 30,700 COEC (Fauna)51000 5% > 857 COEC (Fauna)34700 Nutrient/essential element3290 OK (Max < Threshold)

7.8 OK (Max < Threshold)1900 OK (Max < Threshold)1950 Nutrient/essential element13.5 OK (Max < Threshold)370 5% > 5.31 COEC (Fiora)

6400 Nutrient/essential element230 5% > 21.3 COEC (Flora)263 OK (Max < Threshold)

20000 OK (95% <= 1,440)0.11 OK (Max < Threshold)

2 nd2 OK (Max < Threshold)

0.1 OK (Max < Threshold)6.2 nd

0.46 OK (Max < Threshold)6.2 nd

0.23 OK (Max < Threshold)0.14 OK (Max < Threshold)0.28 OK (Max < Threshold)

0.0288 nd0.16 OK (Max < Threshold)

Long Creek Soils Page 1

Long Creek Soils Screening Data

CLASS DESCRIPTION Max VALUE SCREENING NOTES Findingalpha-Chlordane 0.0144 ndDieldrin 0.15 OK (Max < Threshold)gamma-Chlordane 0.0186 ndHeptachlor epoxide 0.0291 OK (Max < Thr.shold)PCB 1254 0.365 OK (Max < Threshold)ppDDD /1,1-Dichloro-2,2- 0.0159 OK (Max < Threshold)

TCL_VOA 1,1,1-Trichloroothene 0.83 ndToluene 0.0072 OK (Max < Threshold)

Long Creek Soils Page 2

long Creek Sediment Screening Data


CLASS DESCRIPTION Max VALUE SCREENING NOTES Findingmglkg

ANIONS Nitrite, nitrate - nonsp 8.58 Nutrient/essential elementSulfate 160 Nutrient/essential element

EXPLOSIVES 1,3,5-Trinitrobenzene 5.01 OK (>95% < DL)1,3-Dinitrobenzene 1.58 OK (>95% < DL)2,4-Dinitrotoluene 0.502 OK (>95% < DL)Cyclotetramethylenetetran 70.7 OK (>95% < DL)RDX / Cyclonite / Hexahyd 120 OK (>95% < DL)

TAL_METAL Aluminum 16400 ndAntimony 12.4 OK (Max < Threshold)Arsenic 32.2 OK (Max < Threshold)Barium 857 ndBeryllium 1.61 ndCadmium 2.47 OK (Max < Threshold)Calcium 130000 Nutrient/essential elementChromium 120 OK (Max < Threshold)Coba~ 44.2 ndCopper 180 OK (Max < Threshold)Iron 440000 ndLead 7100 OK (Max < Threshold)Magnesium 49500 Nutrient/essential elementManganese 5990 ndMercury 0.699 OK (Max < Threshold)Nickel 120 OK (Max < Threshold)Potassium 1810 Nutrient/essential elementSelenium 2.93 ndSilver 2.12 OK (Max < Threshold)Sodium 686 Nutrient/essential elementThallium 260 ndVanadium 47.9 ndZinc 3930 OK (Max < Threshold)

TCL_BNA 2-Methylnaphthalene 1.3 OK (Max < Threshold)Anthracene 0.072 OK (Max < Threshold)Benzo[blfluoranthene / 3, 0.52 OK (Max < Threshold)Benzo[def)phenanthrene / 11 ndBenzo[k]fluoranthene 0.24 OK (>95% < DL)Bis(2-ethylhexyl) phthala 4.4 OK (Max < Threshold)Chrysene 0.43 OK (Max < Threshold)Di-n-butyl phthalate 2 OK (Max < Threshold)Dibenzofuran 0.26 OK (Max < Threshold)Fluoranthene 0.47 OK (Max < Threshold)Naphthalene / Tar camphor 0.41 OK (Max < Threshold)Phenanthrene 0.57 OK (Max < Threshold)

TCL_PEST 2,2-Bis(p-chlorophenyl)-1 0.14 OK (>95% < DL)alpha·Chlordane 0.0495 ndDieldrin 0.0145 OK (Max < Threshold)gamma-Chlordane 0.03 ndPCB 1260 0.206 OK (Max < Threshold)ppDDD /1,1-Dichloro-2,2- 0.12 OK (Max < Threshold)

TCL_VOA Chlor%nn 0.0229 OK (>95% < DL)Tetrachloroethane /1,1,2 40 OK (Max < Threshold)Toluene 0.44 OK (Max < Threshold)


Long Creek Sediments Page 1

Long Creek Surface Water Screening Data


CLASS DESCRIPTION Max VALUE SCREENING NOTES FindinguglL

ANIONS Nitrite, nitrate - nonsp 5000 utrient/essential elementSulfate 160000 utrient/essential element

EXPLOSIVES 1,3,5-Trinitrobenzene 0.532 OK (Max < Threshold)2,4-0initrotoluene 0.81 OK (Max < Threshold)2,6-0initrotoluene 1.42 OK (Max < Threshold)Cyclotetramethylenetetra 4.94 OK (>95%.LT.OL)Nitrobenzene I Essence 0 4.09 OK (Max < Threshold)ROX I Cyclonite I Hexahy 17 nd

TAL_METAL Aluminum 2340 5%>2,100 COECAntimony 181 ndArsenic 24.3 OK (Max < Threshold)Barium 836 5%>187 COECBeryllium 3.91 OK (Max < Threshold)Cadmium 8.62 OK (>95%.LT.OL)Calcium 180000 utrient/essential elementChromium 81.5 OK (>95%.LT.OL)Copper 124 OK (5%>18.8)Iron 3720 5%>2,930 COECLead 36.4 5%>16.8 COECMagnesium 158000 utrient/essential elementManganese 4330 5%>925 COECMercury 0.247 Max> Threshold" COECNickel 99.2 OK (Max < Threshold)Potassium 27700 utrient/essential elementSelenium 34 OK (>95%.LT.OL)Sodium 100000 utrient/essential elementVanadium 18.3 OK (Max < Threshold)Zinc 3360 5%>107 COEC

TCL_BNA Bis(2-ethylhexyl) phthala 25 OK (Max < Threshold)Oiethyl phthalate 85 OK (Max < Threshold)

TCL_VOA 1,1,1-Trichloroethane 2.9 OK (Max < Threshold)1,1-0ichloroethylene 11, 13 nd1,2-0ichloroethane 1.9 OK (>95%.LT.OL)Chloromethane 2.2 OK (>95%.LT.OL)Toluene 4 OK (Max < Threshold)Trichloroethylene ITrichl 11 OK (Max < Threshold)

"Bio-magnifier

Long Creek Water Page 1

Spring Creek Soils Screening Data


CLASS DESCRIPTION Max VALUE SCREENING NOTES Findingm9/kg

EXPLOSIVES 1,3,5-Trinitrobenzene 90 nd1,3-Dinitrobenzene 0.458 OK (>95% < DL)2,4,6-Trinitrotoluene I a 85000 nd2,4-Dinitrotoluene 76 OK (>95% < DL)2,6-Dinitrotoluene 0.585 OK (>95% < DL)Cyclotetramethylenetetran 32000 ndNitrobenzene I Essence of 19.2 OK (>95% < DL)RDX 1Cyclonite 1Hexahyd 51000 ndTetryll N-Methyl-N,2,4,6 1.96 OK (>95% < DL)

RAD Actinium 228 2 EliminatedAlpha gross 11.5 EliminatedBeta gross 9.4 EliminatedBismuth 214 1.4 EliminatedCesium 137 0.36 EliminatedLead 212 1.5 EliminatedLead 214 1.4 EliminatedPolessium 40 18 EliminatedRadium 226 6.7 EliminatedThallium 208 0.58 Eliminated

TAL_METAL Aluminum 21000 5% > 17,800 COEC (Flora)Antimony 1100 OK (95% <= 19.6)Arsenic 16 OK (Max < Threshold)Barium 32000 OK (Max < Threshold)Beryllium 3.4 OK (Max < Threshold)Cadmium 62 OK (Max < Threshold)Calcium 270000 Nutrient/essential elementChromium 2110 5% > 159 COEC (Flora & Fauna)Cobalt 55.3 OK (Max < Threshold)Copper 290000 OK (95% <= 2,220)Iron 42500 5% > 26,100 COEC (Fauna)Lead 17000 5% > 1,550 COEC (Fauna)Magnesium 20800 Nutrient/essential elementManganese 2790 OK (Max < Threshold)Mercury 1.7 OK (Max < Threshold)Nickel 1500 OK (Max < Threshold)Potassium 4190 Nutrient/essential elementSelenium 0.577 OK (Max < Threshold)Sliver 38 5% > 4.49 COEC (Flora)Sodium 2810 Nutrient/essential elementThallium 110 5% > 34.3 COEC (Flora)Vanadium 47.1 OK (Max < Threshold)Zinc 160000 OK (95% <= 3,450)

TCL_BNA 2-Methylnaphthalene 6 ndAnthracene 2.5 OK (Max < Threshold)Benzo[a]anthracene 0.11 OK (Max < Threshold)Benzo[det]phenanthrene 1 5 ndBis(2-ethylhexyl) phthala 60 ndChrysene 0.55 OK (Max < Threshold)Di-n-butyl phthalate 6.3 ndFluoranthene 0.13 OK (Max < Threshold)Fluorene I 9H-Fluorene 0.095 OK (Max < Threshold)Naphthalene 1Tar camphor 0.39 OK (Max < Threshold)Phenanthrene 3 OK (Max < Threshold)

TCL_PEST 2,2-Bls(p-chlorophenyl)-1 0.0079 OK (>95% < DL)Dieldrin 0.077 OK (Max < Threshold)

TCL_VOA 1,1 ,1-Trichloroethane 10 OK (>95% < DL)1,1-Dichloroethane 6.1 OK (>95% < DL)1,1-Dichloroethylene 11 , 1.7 OK (>95% < DL)

Spring Creek Soils Page 1

Spring Creek Soils Screening Data

CLASS DESCRIPTION

1,2-Dichloroethylenes (ciAcetoneEthylbenzeneTetrachloroethane I 1,1,2Telrachloroelhylenel TelTolueneTrichloroethylene fTrichl

Max VALUEmg/kg

1.10.025

1.40.260.59

100.45

SCREENING NOTES

OK (>95% < DL)OK (>95% < DL)OK (>95% < DL)

OK (Max < Threshold)OK (Max < Threshold)OK (Max < Threshold)OK (Max < Threshold)

Finding

Spring Creek Soils Page 2

Spring Creek Sediment Screening Data


CLASS DESCRIPTION Max VALUE SCREENING NOTES Findingmg/kg

EXPLOSIVES 1.3.5-Trinitrobenzene 4.76 nd2.6-Dinitrotoluene 0.852 OK (>95% < DL)Cyclotetramethylenetetra 55 ndNitrobenzene I Essence 0 6.55 OK (>95% < DL)RDX I Cyclonite I Hexahy 3.1 nd

TAL_METAL Aluminum 13000 ndArsenic 16 OK (Max < Threshold)Barium 1960 ndBeryllium 1.71 ndCalcium 30300 utrientlessential elementChromium 39.8 OK (Max < Threshold)Cobalt 33.7 ndCopper 315 OK (Max < Threshold)Iron 25800 ndLead 250 OK (Max < Threshold)Magnesium 4780 utrientlessential elementManganese 2250 ndMercury 0.407 OK (Max < Threshold)Nickel 32.6 OK (Max < Threshold)Potassium 1240 utrientlessential elementSelenium 1.82 ndSilver 2.4 OK (Max < Threshold)Sodium 355 utrientlessential elementThallium 13.5 OK (>95% < DL)Vanadium 46.3 ndZinc 349 OK (Max < Threshold)

TCL_BNA Benzo[defJphenanthrene I 0.45 ndBenzo[k]fluoranthene 0.12 OK (>95% < DL)Chrysene 0.22 OK (Max < Threshold)Fluoranthene 0.28 OK (Max < Threshold)

TCL_VOA Tetrachloroethylene I Tet 0.0041 OK (Max < Threshold)


Spring Creek Sediments Page 1

Spring Creek Surface Water Screening Data



EXPLOSIVES 1,3,5-Trinitrobenzene 0.553 OK (Max < Threshold)2,4,6-Trinitrotoluene I a 16.1 OK (Max < Threshold)Cyclotetramethylenetetra 190 ndRDX I Cyclonite I Hexahy 470 nd

TAL_METAL Aluminum 9710 5% > 6,400 COECArsenic 34.2 OK (Max < Threshold)Barium 4240 5% > 296 COECCadmium 10.9 OK «5%)Calcium 70600 utrient/essential elementChromium 31.3 OK (Max < Threshold)Copper 80.7 5% > 33.1 COECIron 8190 5% > 7,570 COECLead 20.7 5% > 13 COECMagnesium 33200 utrient/essential elementManganese 195 5% > 172 COECNickel 70.7 OK (Max < Threshold)Potassium 15300 utrient/essential elementSelenium 3.51 OK (Max < Threshold)Sodium 144000 utrient/essential elementVanadium 589 5% > 30.5 COECZinc 243 OK (Max < Threshold)

TCL_VOA Toluene 4 OK (Max < Threshold)

Spring Creek Water Page 1

Skunk Creek Tributaries Solis Screening Data


CLASS DESCRIPTION Max VALUE SCREENING NOTES Findingm9/kg

RAD Actinium 228 1.5 EliminatedAlpha gross 8.33 EliminatedBeta gross 7.96 EliminatedBismuth 214 1.3 EliminatedCesium 137 1 Eliminatedlead 212 1.2 Eliminatedlead 214 1.1 EliminatedPotassium 40 14 EliminatedRadium 226 6.6 EliminatedThallium 208 0.46 Eliminated

TAL_METAL Aluminum 16500 Max > Threshold COEC (Flora)Arsenic 20 OK (Max < Threshold)Barium 206 OK (Max < Threshold)Beryllium 0.998 OK (Max < Threshold)Calcium 20900 Nutrient/essential elementChromium 22.4 Max > Threshold COEC (Flora & Fauna)Coba~ 17 OK (Max < Threshold)Copper 17 OK (Max < Threshold)Iron 32600 Max> Threshold COEC (Fauna)lead 36 Max> Threshold COEC (Fauna)Magnesium 5210 Nutrient/essential elementManganese 1750 OK (Max < Threshold)Mercury 0.109 OK (Max < Threshold)Nickel 46.3 OK (Max < Threshold)Potassium 1530 Nutrient/essential elementSelenium 0.546 OK (Max < Threshold)Silver 15.5 Max > Threshold COEC (Flora)Sodium 269 Nutrient/essential elementVanadium 41.6 OK (Max < Threshold)Zinc 270 OK (Max < Threshold)

TCl_BNA Naphthalene / Tar camphor 0.004 OK (Max < Threshold)TCl]EST 2,2-Bis(p-chlorophenyl)-1 0.0473 nd

delta-Hexachlorocyclohexa 0.0353 OK (Max < Threshold)

NOTE: Fewer than 20 samples ~ any value greater than threshold =COEC

Skunk R. Tribs Soils Page 1

Skunk River Tributaries Sediment Screening Data


EXPLOSIVES 1,3,5-Trinitrobenzene1,3-Dinitrobenzene2,4,6-Trinitrotoluene I a2,4-Dinitrotoluene2,6-DinitrotolueneCyclotetramethylenetetranRDX I Cyclonite I Hexahyd

TAL_METAL AluminumArsenicBariumBerylliumCadmiumCalciumChromiumCobaltCopperIronLeadMagnesiumManganeseMercuryNickelPotassiumSeleniumSilverSodiumThalliumVanadiumZinc

TCL_BNA Bis(2-ethylhexyl) phthalaDi-n-butyl phthalateFluorantheneNaphthalene I Tar camphoPhenanthrene

CLASS DESCRIPTION Max VALUEmg/kg

8204.374.557.91.7

260014000854013.74121.8

1.5730800

38.846.346.9

2590041

117007130

0.18933.712901.16

27352

1442.41851.51.4

0.110.1

0.072

SCREENING NOTES

ndndndndndndndnd

OK (Max < Threshold)ndnd

OK (Max < Threshold)utrientlessential elementOK (Max < Threshold)

ndOK (Max < Threshold)

ndOK (Max < Threshold)utrientlessential element

ndOK (Max < Threshold)OK (Max < Threshold)utrientlessential element

ndOK (Max < Threshold)utrientlessential element

OK (>95% < DL)nd

OK (Max < Threshold)OK (Max < Threshold)OK (Max < Threshold)OK (Max < Threshold)OK (Max < Threshold)OK (Max < Threshold)

Finding


Skunk R. Tribs Sediments Page 1

Skunk River Tributaries Surface Water Screening Data



EXPLOSIVES 1,3,5-Trinitrobenzene 1.07 OK (Max < Threshold)2,4,6-Trinitrotoluene I a 8.29 OK (Max < Threshold)Cyclotetramethylenetetra 30.8 ndRDX I Cyclonite I Hexahy 250 nd

TAL_METAL Aluminum 2440 Max> Threshold COECArsenic 3.09 OK (Max < Threshold)Barium 192 Max> Threshold COECCalcium 113000 utrienVessential elementIron 3010 Max> Threshold COECLead 9.76 Max> Threshold COECMagnesium 37400 utrienVessential elementManganese 373 Max> Threshold COECPotassium 6050 utrienVessential elementSelenium 3.73 OK (Max < Threshold)Silver 12.4 Max> Threshold COECSodium 27000 utrienVessential elementVanadium 20 Max> Threshold COECZinc 119 Max> Threshold COEC

TCL_VOA Carbon disulfide 27 Max> Threshold COECToluene 4 OK (Max < Threshold)

NOTE: Fewer than 20 samples were collected; therefore,maximum value represents 5% exceedance.

Skunk R. Tribs Water Page 1

APPENDIX B

ESTIMATION OFEXPOSURE POINT CONCENTRATION

APPENDIX B

Estimation of Exposure Point Concentrations

Data for derivation of exposure point concentrations was taken from two sources. The primary source was

field measurements ofcontaminants in soil, fish tissue, small mammal tissue, water and sediment taken by

Harza during the summer of 1997. Where data were not available, or when a more complete database

existed, we utilized the electronic database files provided by IAAAP, who reportedly received them from

JAYCOR, Inc. The database files were in the format supported by Microsoft Access (version 97) and were

named SoilsJs.mdb (19,136 kB), WaterJs.mdb (26,080 kB) and Ip_data.mdb (28,800 kB).

Exposure point concentrations of COEC were taken as the 95% upper confidence limit (UCL) of all

measurements. This estimates the central tendency of the COEC concentration as well as accounts for

uncertainties in the accuracy ofthe measurements. In estimating the 95%UCL, nondetect values were taken

as 50% of the MOL. When relatively few samples were obtained from a site, the 95%UCL tended to

overestimate a central tendency, that is, to exceed the maximum measurements at the site. In instances where

the 95%UCL exceeded the maximum concentration, we used the maximum as the exposure point

concentration.

Soils

JAYCOR's measurements of contaminant concentrations in the top 24 inches of soil were used in many

computations ofexposure point concentrations. Below we provide the corresponding locations of JAYCOR

soil sampling stations with Harza's risk assessment locations.

Harza Site JAYCOR Site Designation

Designation

SRTl RBK-SS-18, RBK-SS-23, RBK-SS-26

LCI RBK-SS-I, RBK-SS-05, RBK-SS-13, RBK-SS-17, RBK-SS-IO,

RBK-SS-15, RBK-SS-21

LC2 none

BC9 RBK-SS-02, RBK-SS-06, RBK-SS-03, RBK-SS-07, RBK-SS-25

BCIO none

BC3 RI8



Harza Site JAYCOR Site Designation

Designation

BC6 none

SCI RBK-SS-07, RBK-SS-16, RBK-SS-II, RBK-SS-27, RBK-SS-22,

RBK-SS-08, RBK-SS-04, RBK-SS-20

SC2 RBK-SS-19, RBK-SS-12, RBK-SS-24

SC4 all samples from watershed

Water

All surface water measurements for a given stream were combined to obtain the 95%UCL. The exposure

concentrations are for total metals in surface water, as that is the basis ofJAYCOR's measurements in the

database. Use of exposure point concentrations calculated from total metal concentrations results in

considerable over prediction of exposures, as only a fraction of total metals are bioavailable. All surface

water measurements for a given stream were combined to obtain the 95%UCL.

On October 27, 1997, we collected water samples for determination of total and filtrable metals in grab

samples taken from reference and impacted sections of Spring Creek, Long Creek, and Brush Creek. These

data were used to adjust exposure concentrations downward to reflect the bioavailable fractions.

Sediment

Below we provide the corresponding locations of JAYCOR sediment sampling stations with Harza's risk

assessment locations.

ERAASite Harza's Groundwater JAYCOR Site Designation

Designation Data Gap Study

SRTI 7Q RBW-SD-93, RBW-SD-89, RBW-SD-90

SRT2 7P RBW-SD-92, RBW-SD-88, RBW-SD-II

LCI RBW-SD-99, RBW-SD-98

LC2 7N RBW-SD-55

LCn RBW-SD-I03, RBK-SD-03, RBW-SD-I02 I


March 19, 1998Paga 8·2

ERAASite Harza's Groundwater JAYCOR Site Designation,

Designation Data Gap Study

,

LCT2 RBW-SD-59, RBW-SD-60 ,

LCn RBW-SD-59, RBW-SD-61, RBW-SD-58

LCT4 RBW-SD-66 iI

BC9 RBK-SD-08, RBK-SD-04,

BClO RBW-SD-43, RBW-SD-44, RBW-SD-46

BCl 7E

BC2 7F RBW-SD-36, RBW-SD-37

BC3 71 RBW-SD-Ol, RBW-SD-02

BC4 RBW-SD-03, RBW-SD-04

BC5 7J RBW-SD-32, RBW-SD-3l

BC6 7K RBW-SD-30, RBW-SD-3l

BC7 RBW-SD-29, RBW-SD-30

BC8 7L,7M

SCI RBK-SD-05, RBW-SD-17, RBW-SD-19, RBW-SD-20

SC2 7A RBW-SD-25, RBW-SD-05, RBW-SD-23

SC3 7B RBW-SD-27

SC4 7C RBW-SD-28

SC5 7D

SC6 7D


March 19, 1998Page B~3

Soil_Exposure: 10/17/97 14:55

Estimated Soil Exposure Values for Sites in the Brush Creek Drainage(Minimum of: 95%UCL or Maximum Value)

UCL or Max(Max if UCl < Max)

CLASS DESCRIPTIO BC10 BC3 BC9 DRAINAGEEXPLOSIVES l,3.S·Trinitrobenzene 4.66 0.244 0.244 1.21

(23000)

2,4.6·Trinitrotoluene /a 45. 0.228 0.228 27.106(100000)

Cyclotetramsthylenetetran 860. 0.333 0.333 11.232(6700)

Tetryll N·Methyt·N,2,4,6 0.366 0.366 0.366 0.466(8300)

RDX I Cyclonit8 I Hexahyd 6,900. 0.294 0.294 7.036(7200)

TAL_METAL Aluminum 12,100. 2,800. 16,315.998 10,555.963(16800) (21800)

Chromium 145, 90.6 21.767 37.81(21.9) (1530)

Iron 37,500. 7,370. 19,264.2 18,588.894(21300) (94000)

lead 27. 21.5 28.586 206.283(41) (13000)

Mercury 0.14 0.494 0.025 0.446(2000)

Silver 3.49 88. 0.295 0.569(260)

Thallium 3.31 3.31 9.66 18.321(67.3)

TCl_BNA Benzo{def]phenanthrene I O. 0.017 0.017 0.968(100)

Bis(2·ethythexyt) phthala O. 0.31 1. 1.126(15)

Di-n-butyl phthalate O. 0.031 0.031 0.554

Page 1

CLASS DESCRIPTIO

Soil_Exposure: 10117/9714:55

UCL or Max(Mex if UCL < Mex)

BC10 BC3 BC9 DRAINAGE(6.2)

Dibenzofuran O. 0.018 0.018 0.119(30)

alpha-Chlordane

gamma-Chlordane

o.

o.

o.

o.

o.

O.

880.

640.

PCB 1260 O. O. 0.04 2.398(100)

ppODD /1,1-Dichloro-2,2- O. O. 0.004 0.794(1200)

DOE - 2.2-Bis(p-chlorophenyl)-1 O. O. 0.004 2.007(21000)

DDT - 2,2-Bis(p-chlorophenyl)-1 O. O. 0.004 0.267(77)

Page 2

Sed_Exposure: 101'719714:55

Estimated Sediment Exposure Values for Sites in the Brush Creek Drainage(Minimum of: 95%UCL or Maximum Value)

UCL or Max(Max if UCL < Max)

CLASS DESCRIPTIO BC10 BC3 BC9 BC4 BC7 BCS BC5 BC2 DRAINAGEEXPLOSIVES 1,3,6-Trinitrobenzene 100. 0.244 0.244 0.244 0.244 0.244 0.244 0.244 1.248

(100)

2,4,6-Trlnitrotoluene I a 34. 3.37 0.228 0.228 0.228 0.228 0.228 0.228 8.078(270000)

Cyclotetramethylenetetran 11,000. 0.333 0.333 0.333 0.333 0.333 0.333 0.333 22.874

(28000)

Tetryll N-Methyl-N,2,4,6 0.386 0.366 0.366 0.366 0.366 0.368 0.366 0.366 0.386

RDX I Cyclonite I Hexahyd 170. 2.05 0.294 1.03 0.294 1.38 1.38 0.294 14.229(100000)

TAL_ME1AL Aluminum 3,600. 4,790. '3,900. 2,090. 9,480. 5,340. 5,340. 10,300. 12,637.192

(210000)

Chromium 554. 10.1 19.5 21.6 18.6 13.8 15.8 34.1 43.69(1360)

Iron 27,400. 8,630. 16,300. 11,200. 31,300. 10,800. 14,100. 33,700. 20,958.757(86100)

lead 110. 10.7 15.7 8.9 65. 10.8 11.8 10.3 103.089(5630)

Mercury 0.279 0.025 0.025 0.025 0.025 0.025 0.025 0.025 0.224

(3)

Silver 0.791 0.295 0.295 0.999 1.02 2.33 2.63 2.39 1.042(24)

Thallium 3.31 3.31 3.31 3.31 3.31 3.31 3.31 3.31 12.615(31.8)

Barium 24,000. 91.9 192. 113. 418. 193. 193. 234. 552.649

(24000)

Beryllium 1.59 0.25 1.29 0.25 1.72 0.829 0.834 1.26 1.174(2.82)

Selenium 2.76 0.647 1.1 0.125 1.36 0.125 1.09 0.125 0.641(2.98)

Page 3

Sed_Exposure: 10/17/9714:55

UClor Max

(Max If UCl < Max)

CLASS DESCRIPTIO BC10 BC3 BC9 BC4 BC7 BC6 BC5 BC2 DRAINAGEZinc 335. 35. 74.6 28.6 60.4 45.6 45.6 55.2 198.441

(7650)

Cobalt 56.3 6.94 8.27 10.4 79.8 8.42 6.51 14.8 13.895(79.8)

Manganese 4,620. 214. 470. 683. 8,200. 591. 496. 567. 1,223.328(8840)

Vanadium 52.4 16.6 33. 17.3 64.9 19. 21.4 32.7 29.838(64.9)

TCl_BNA Benzo[def]phenanthrene I 1.2 0.017 0.017 0.017 0.017 0.017 0.017 0.017 0.05(1.2)

TCl_VOA Chloromethane 0.004 0.004 0.004 0.004 0.004 0.004 0.004 0.004 0.036(0.48)

TCl_PEST ppDDE 12,2-Bis(p-chlorophenyl)·1 0.004 0.004 0.004 0.004 0.004 0.004 0.004 0.004 0.01(0.034)

ppOOT 12,2-Bis(p-chlorophenyl)·1 0.004 0.004 0.004 0.004 0.004 0.004 0.004 0.004 0.013(0.05)

Page 4

H20_Exposure: 10/17/97 14:55

Estimated Water Exposure Values for S~es in the Brush Creek Drainage(Minimum ot 95%UCL or Maximum Value)


CLASSEXPLOSIVES

DESCRIPTIO1,3,5-Trinitrobenzene

2,4,6-Trinitrotoluene 1a

Cyclotetramethylenetetran

Tetryll N-Methyl-N,2,4,6

RDX 1Cyclonite 1Hexahyd

Aluminum

Barium

Beryllium

Chromium

Cobalt

Copper

Total5.993(880)

58.926(8000)

51.292(740)

1.793(12.5)

248.428(5400)

3,279.306(740000)

132.097(996)

3.06

(56)

14.874(1600)

15.627(240)

21.078

(320)

Page 5

H20_Exposure: 10/17/9714:55

UCl or Max(Max if UCl < Max)

CLASS DESCRIPTIO TotalIron 4,931.732

(2500000)

lead 21.64(660)

Manganese 304.597(19000)

Mercury 0.189(5.9)

Selenium 1.938(30)

Silver 10.446(2130)

Thallium 20.531(62.5)

Vanadium 7.379(31.3)

Zinc 156.677(1580)

TCl_BNA Benzo[deflphenanthrene / 2.131(8.5)

TCl_VOA Chloromethane 1.885(10)

Page 6

SoiLExposure: 10/1719715:33

DRAINAGE1.423

(21)

Estimated Soil Exposure Velues for Sites in the Long Creek Drainage(Minimum of: 95%UCL or Maximum Value)

UCL or Max(Max) if UCL < Max

LC2 LC11.045 O.

CLASS DESCRIPTIOEXPLOSIVES 1,3,5-Trinitrobenzene

2,4,6-Trinitrotoluene / a 0.96 O. 118.743(25000)

Cyclotetramethylenetetran 0.635 O. 12.04(130001

2,4-Dinitrotoluene 0.21 0.07 0.454(13.2)

RDX / Cyclonije / Hexahyd 0.49 O. 18.66(75000)

TAL_METAL Aluminum O. 14,744.156 12,289.671119200) (414001

Chromium 35.8 20.061 36.236(27.41 (2800)

Iron O. 20,379.626 21,081.683(26800) (170000)

Lead 19. 25.352 204.011(51 ) (510001

Silver 0.402 0.295 1.398(370)

Thallium 17.15 3.31 18.667(230)

Benzo[defjphenanthrene / o. 0.017 0.167(2)

Bis(2-ethylhexyl) phthala o. 0.31 2.324(151

Page 1

CLASS DESCRIPTIO

SoiLExposure: 10/17/9715:33

UCl or Max(Max) if UCl < Max

lC2 lCl DRAINAGE

Di-n-butyl phthalate

TCl_PEST alpha-Chlordane

gamma-Chlordane

o.

o.

o.

0.031

o.

o.

0.644(6.2)

0.014

0.019

ppDDE /2,2-Bis(p-chlorophenyl)-1 O. 0.012 0.014(0.0198) (0.034)

ppDDT /2,2-Bis(p-<:hlorophenyl}-1 O. 0.016 0.023(0.0288) (0.05)

TCl_VOA 1,1,1-Trichloroethane O. 0.002 0.408(0.83)

Page 2

Sed_Exposure: 10117/97 15:33

Estimated Sediment Exposure Values for Sites in the long Creek Drainage(Minimum of: 95%UCl or Maximum Value)


CLASS DESCRIPTION LC2 LCl lCTl LCT2 LCTS LCT4 DrainageTAL_METAL Aluminum 1,740. 4,690. 13,200. 10,500. 10,500. 2,310. 8,105.179

(16400)

Iron 6,670. 9,560. 19,200. 18,600. 17,400. 11,100. 23,099.851(440000)

lead 5.25 14. 21.1 39. 17. 13.1 44.781(7100)

Thallium 3.31 3.31 3.31 3.31 3.31 3.31 10.331(260)

Barium 45.3 95.9 224. 180. 180. 87.4 180.997(857)

Beryllium 0.821 0.25 1.19 1.42 0.998 0.92 0.93(2.5)

Mercury 0.025 0.025 0.025 0.025 0.025 0.025 0.049(0.699)

Selenium 0.125 0.445 0.966 1.54 1.09 0.125 0.838(2.93)

Zinc 20.2 33.5 97. 372. 61.3 97.2 131.296(3930)

Coba~ 5.37 17.3 9.02 7.76 8.94 13.6 10.148(44.2)

Manganese 361. 700. 746. 723. 648. 644. 785.857(5990)

Vanadium 11.4 19.7 33.3 27.2 27.2 16.6 25.342(47.9)

TCl_BNA Benzo[defJphenanttnoo I 0.017 0.017 0.1 0.6 0.017 0.35 0.119(11 )

PageS

CLASS DESCRIPTIONTCL_PEST alpha-ehlordane

sed_Exposure: 1011719715:33

UCL or Max(Max) i1 UCL < Max

LC2 LC1 LCnO. O. O.

LCT2O.

LCT3O.

LCT4O.

Drainage0.05

gamma-Chlordane o. o. o. o. o. o. 0.03

ppDDE 12,2-Bis(p-ehlorophenyl)-1 0.004 0.004 0.004 0.004 0.004 0.004 0.007(0.14)

ppDDT 12,2-Bis(p-chlorophenyI)-1 0.004 0.004 0.004 0.004 0.004 0.004 0.00510.05)

TCL_VOA 1,1-Dichloroethylene/1, 0.002 0.002 0.01 0.002 0.002 0.002 0.005(0.135)

EXPLOSIVES RDX I Cyclonile I Hexahyd 0.294 0.294 0.294 7.92 0.294 0.294 0.874(1201

Page 4

H20_Exposure: 10/17/9715:33

DESCRIPTIOAluminum

Estimated Water Exposure Values for Sites in the Long Creek Drainage(Minimum of: 95%UCL or Maximum Value)


Total872.537

(2340)

CLASSTAL_METAL

Barium 127.135(836)

Beryllium 2.676(3.91)

Cobalt 12.5

Iron 1,233.081(3720)

Lead 4.174(36.4)

Manganese 361.046(4330)

Mercury 0.126(0.247)

Selenium 2.134(34)

Thallium 7.387(62.5)

Vanadium 9.42(18.3)

Zinc 39.204(3360)

Page 5

H20_Exposure: 10/17/9715:33

CLASS DESCRIPTIO

Benzo[def)phenanthrene /

1,1-Dichloroethylene /1,

UCLorMax(Max if UCL < Max)

Total

1.4

0.601(13)

EXPLOSIVES RDX / Cyclonite / Hexahyd 0.935(17)

Page 6

Spring Soils

Estimated Soil Exposure Values for Sites in the Spring Creek Drainage(Minimum of: 95%UCl or Maximum Value) Units = mg/kg

UCl or Max

I I(Max) if UCl < MaxCLASS IDESCRIPTIO ! SC1 SC2 RAINAGEEXPLOSIVE 11,3,5-Trinitrobenzene 0.244 0.244 6.873

(90)

i

2,4,6-Trinltrotoluene I a 0.228 0.228 751.83(85000)

Cyclotetramethylenetetra 0.333 0.333 3059.952(32000)

,RDX I Cyclonite I Hexahy i 0.294 0.294 642.692

I (51000), 11 i

TAL METAL ,Aluminum 115348.803 15300. 11730.178(21000)' (21000)

I 1 ,I

IChromium 20.615 22.1391 47.115

1 (26) (22.6)' (2110)

I I , 1_.

1,

j/ron 121595.887 I 26100.1 19122.688, (26400) i (42500)

I,

iI

, ilead 20.712 52.584 233.085

I (27) (53) (17000)•..i

1 1'Silver 0.295: 0.2951 1.28, I (38),

1 I-----.-rrhallium , 9.978 3.31 20.147

(18.2) (110)

I!

TCl BNA IBenzo[deijphenanthrene I 0.017' 0.017 0.073

i (5)

, i ,Bis(2-ethylhexyl) phthala I 0.503 1.21 0.794

I (0.93), i (60),I .._--

IIDi-n'-bUtyl phthalate 0.031' 0.031 0.566

-(6.3)

2-Methylnaphthalene 1 0.025 0.025 0.073i ! (6)

Page 1

Spring Sediments

Estimated Sediment Exposure Values for Sites in the Spring Creek Drainage(Minimum of: 95%UCl or Maximum ValuelJnits =mg/kg I

UClorMax I(Max) if UCl < Max

CLASS DESCRIPTIO SC1 SC2 SC3 SC4 Drainage

EXPLOSIVE 1.3,5-Trinitrobenzene 0.244 0.244 0.244 0.244 4.76

I

ICyciotetramethylenetetra 0.333 0.333 0.333 0.333 55.

RDX I Cyclonite I Hexahy: 0.294 0.294 0.294 0.294 3.1

TAL_METAL Aluminum 8370. 6070. 3480. 1420. 13000.

I ,ilron I 25800. 21600. 7950. 4920. 25800.

I II

Ilead , 250.1 22 8.81 443 250.

!- ,i ,

:iBarium 323. 254. 93.2 97.: 1960.,

1, ,

I ,

.Beryllium ! 151 1.11 0.25' 0.25 1.71, ,

I iIiCopper 10.6 104 6.331 2.72 315.

i I

,

!Selenium I 0.717 1.82' 0.125 0.125' 1.82

I i I

I

- I,Cobalt 33.7 16.8 5.64 3.96 33.7

i ,,,

IManganese 2250. 1850. 285. 207. 2250

I,

IVanadium , 39.8 33.21 124 7.11 46.3, ,

i

ITCl BNA IBenzo[defjphenanthrene I 0.063, 0.017 0.017' 0.0171 045

I i I I

Page 1

H20_Exposure: 10/8/9710:26

Estimated Water Exposure Values for Sites in the Spring Creek Drainage(Minimum of: 95%UCl or Maximum Value)

UCl or Max(Max if UCl < Max)

CLASSTAL METAL

DESCRIPTIOAluminum

Barium

Beryllium

Cobalt

Total2,503.968

(9710)

311.728(4240)

2.5

12.5

Iron 2,464.962(8190)

Lead 9.262(20.7)

Manganese 104.173(195)

Selenium 1.684(3.51)

Vanadium 30.287(589)

Copper 13.187(80.7)

TCl_BNA Benzo[def]phenanthrene 1 1.4

Page 1

CLASSEXPLOSIVES

H20_Exposure: 10/8/9710:26

DESCRIPTIO1,3,5-Trinitrobenzene


RDX / Cyclonite / Hexahyd


Total0.299

(0.648)

16.509(190)

90.302(470)

Page 2

Soil_Exposure: 10/17/9715:57

Estimated Soil Exposure Values for Sites in the Skunk River Tributaries Drainage(Minimum of: 95%UCL or Maximum Value)

DESCRIPTIOAluminum

UCLor Max(Maxi if UCL < Max

SRTl DRAINAGE13,509.471 16,500.

(16500)

Chromium

Iron

Lead

Silver

ppDDT / 2,2-Bis(p-chlorophen

ppDDE / 2.2-Bis(p-chlorophen

18.735(22.4)

28,830.944(32600)

32.

0.295

0.004

0.004

16.788(22.4)

27.666.687(326001

36.

15.5

0.047

0.004

EXPLOSIVES RDX / Cyclonite I Hexahyd 0.294 0.44(0.49)

Page 1

Skunk Sediments

Estimated Sediment Exposure Values for Sites in the Skunk River Tributaries Drainage(Minimum of: 95%UCl or Maximum Value) Units = mg/kg


CLASS DESCRIPTIO SRT1 SRT2 DrainageTAL METAL Aluminum 7990. 5940. 8388.854

I (8540)

Iron 18200. 23700. 18584.989(25900)

lead 15. 23. 19.152

I (41)I

,

ISilver 6.28 0.295 4.686--, (27), 1

,Barium,

133.' 187. 181.201I0-

(412)I

1

1Beryllium , 1.42 1.66 1.627, 1 (1.8), ,

,

'Cobalt , 9.89 18. 16.93, , , (46.3)

I

Manganese , 926. 1350. 1541.269I i (7130)

I,

,I I

IVanadium 28.81 30.31 29.446

- (42.4)!

I

:

!Zinc 1 41. 71.4 62.324

--(185)

I

EXPLOSIVE 2,4-Dinitrotoluene 0.212 0.212 1 0.289

I (7.9)

I

2,6-Dinitrotoluene 0.262 0.262 0.298,(1.7)

,

,

1,3,5-Trinitrobenzene 0.244 0.244 15.7331

,

i (820)

Page 1

Skunk Sediments

I

1.3-Dinilrobenzene 0.248 0.248 0.512(4.37)

I!2,4.6-Trinilrotoluene I a 0.228 0.228 0.491

(4.55)

i!

,Cyclotetramethylenetetra 0.333 0.333 65.326(2600)

j i

RDX I Cyclonite I Hexahy 0.294 0.294 279.26(14000)

1

TCl VOA ICarbon disulfide 0.002 1 0.002' 0.002i I I

Page 2

H20_Exposure: 10/8/9710:23

Estimated Water Exposure Values for Sites In the Skunk Tributaries Drainage(Minimum of: 95%UCL or Maximum Value)

UCL or Max

(Max if UCL < Max)

CLASSTAL_METAL

DESCRIPTIOAluminum

Barium

Bervllium

Cobalt

Total2,440.

116.234(192)

2.5

12.5

Iron 2,933.67(3010)

Lead 6.046(9.76)

Manganese 322.449(373)

Vanadium 11.372(20)

Zinc 21.151(119)

Silver 4.965(12.4)

TCL_VOA Carbon disulfide 17.655

(27)

Page 1

CLASSEXPLOSIVES

H20_Exposure: 10/8/97 10:23

DESCRIPTIOl,3,5-Trinitrobenzene

l,3-Dinitrobenzene

2,4,6-Trinitrotoluene 1a

2,4-Dinitrotoluene

2,6-Dinitrotoluene


RDX 1Cyclonite 1Hexahyd


Total0.57

(1.07)

0.306

5.684(8.29)

2.25

0.395

30.8

250.

Page 2

APPENDIXC

EXPOSURE AND RISK ESTIMATION

APPENDIX C

Exposure and Risk Estimation

Exposures were estimated using a combination offield measurements and predictive modeling. Exposure of

terrestrial animals to COECs was estimated as the sum of exposure from food (Ee), water (Ew) and soil (E,)

ingestion. Dermal and inhalation exposures were assumed to be negligible. Bioconcentration factors (BCF)

for vegetation, aquatic animals and terrestrial animals were taken from the literature (Baes et al. 1984,

Schneider et al. 1995, Garlen and Trabalka 1983, Veith et al. 1979). In some cases, BCF literature values

were unavailable, specifically for some explosives. In these cases, the BCF was estimated from the octanol

water partition coefficients (K,.,) as described in the following equations. BCF for vegetation (BCF,) and for

terrestrial herbivores (BCFt> were estimated using the equations of Travis and Arms (1988). BCF for aquatic

animals (BCF.) was estimated using the equation provided by Mackay (1982):

logBCFv=1.588 -O.578 ologKow

logBCF,= 1.033 o logKow -7. 735

logBCFa=logKow-1.32

Vegetation COEC residues were estimated as the product of BCF, and soil COEC exposure point

concentrations. Two sources of information on soil contamination were used. In most cases, the soil

contaminant database from JAYCOR was used to estimate exposure point concentrations (Appendix B), as

the lower of the maximum or the 95% VCL ofthe arimethic mean of log-transformed data. Where data were

not available, or were considered to be outdated, data from Harza's 1997 field activities were used.

The daily COEC dose from vegetation ingestion was estimated as the product of the estimated residue

concentration, food intake by the consumer in an average day, and the proportion of vegetation in the

consumer's diet. Wildlife reference values for food and water ingestion, body weight and diet composition

were taken from VSEPA (1993). Seasonal variations in diet composition were ignored and annual averages

were used when seasonal data were available.

Iowa Army Ammunition PlantEcological Risk Assessment Addendum fOraft Final}

March 19, 1998Page C·,

Standard Animal Values

Parameter Mouse Bald Eaele MallardBodv weight (ke) 0.022 4 1.1

Food intake (kelke-d) 0.15 0.12 0.5133

Water intake (kelk.-d) 0.04 0.036 0.057

Soil intake (portion of diet) 0.02 0.02 0.02

ExPosure modification rate 1 0.05 0.4

Diet

Invertebrates 0.214 NA 0.7

Ve.etation 0.786 NA 0.3

Fish NA 0.767

Mammals NA 0.068

Birds NA 0.165NA - Not apphcable.

COEC dose from water ingestion was estimated as the product of daily water requirement and surface water

COEC 95% VCL ofthe mean. Soil ingestion rates were taken directly from Beyer et a1. (1994) or estimated

where Beyer's field measurements were not available. In the case ofbald eagle, soil ingestion was assumed

to be two percent of daily food intake.

Bald eagle is known to prefer fish as its principal food. VSEPA (1993) provides data on the composition of

eagle diets. Based upon those data, our daily dose estimates used the following dietary composition: 77% fish,

7% small manunals, and 16% birds. COEC residues in eagle prey were either measured, or estimated

assuming steady state conditions, and available bioconcentration factors, diet composition and Km. values.

Food chain effects were accounted for in the dose estimated for terrestrial animals taken from Baes et a1. (1984)

and Garlen and Trabalka (1983). Exposure modification rates (EMR) were assumed to account for migration

and feeding in off-site areas; bald eagle EMR was assumed to be 5%, a conservative estimate. Bald eagle tend

to feed in expansive areas of open water. Very little open water exists in the Brush Creek watershed, and

eagles would not tend to feed there, rather preferring the opportunities along the Mississippi River, Skunk River

and, perhaps, Mathes Lake.

The attached spreadsheets provide a complete record ofwatershed-specific dose estimates to the ecological

receptors white-footed mouse and to the threatened species bald eagle. To address the possibility of risk to

wide-ranging predators that are not limited to feeding in one watershed, we also prepared a basewide risk

assessment. The receptor used was red-tailed hawk.


March 19, 1998Page C~2

Lastly, we estimated risk to potential receptors from feeding in contaminated areas following remedial or

removal actions. Exposure point concentrations we used for this were the soil PRGs. Receptors ofconcern

were a smaIl rnammal (white-footed mouse) in terrestrial areas andMyotis bats, a flying insectivorous marnmal

who feeds over aquatic areas. Bats were chosen as a receptor of concern as the remediation wetlands at Line

I and Line 800 will produce insects that may be fed upon by various birds, amphibians, reptiles and mammals.


March 19, 1998Page C-3

modeLcoef.xls

coefficients

DESCRIPTIO log Kow Aquatic BCF Plant BCF Wildlife BAF References Wildlife1-,3,-5-Trfrlitrobenzerie ' 1.-1a ---6.36 - 8.1-3.0E:oiDsE-PA-1997, Travis &Arms 1988- ---- Beef-----1-,3--D-iriitrob"nzene-- -- 1.8 3.0 3.5 1.3E-00 - --- ------------- ,-- - --Beer--

12,6-Dinilr()!~llJene~===n, __ ,_-~ =.- '::'::4.8 1!-0~~__ - '_ ,O:oro S~h"-eide~ et al 199~:_IJSACE_I996 ------. _ ~ef =2,4-Dinijrotoluene 2 12 I.E-04 0_003 USEPA 1978, Schneideretal1995, USACE 1996 Beef2,4,6-Trinitrotoluene"!a---- {46------1.4-1~E:04- -0.0013 liSACE199i:l; Schneider et al 199s----- -- Beef-'-Te-t;y-I'-N~,;fethyl:N,:i:4]-r--T.65----:i.1--T:ir-- 9.3E~07 Travis-&-Arms-I-98-8;JAYCOR 1996 - -Beef-----------f----,-~----------- ----------- - --------~clotetramethylenet~"-a 0.26 (J,12.8 3.4E-08 T~avis& Arms 1988, JAYCOR 1996 Beef__RDX' Cyclonite' Hexahy 3.45 135 11 6.7E-05 Schneider et al1995, Travis &Arms 1988 BeefAluminu"'----__ - - ~231 __0,<>o0l1.__ __ O.OO~ .Bohn eta11979, Baes et a11984 _ BeefBarium 0.15 0.00015 Baes et al1984 Beef

i"BCCery=mC::um=------- - -- - -- -0~01-- 0~001 Ba-es-e-t"'1984 --Beef---- -------------------- ------- --------,---------------- -----------Chromium _ 3 __0~007(; 0.0055 Will &Suter 1994, Baes et al1984 BeefCobalt 0_02 0.02 Baes et al 1984 Beef-_._-_._-Copper "I 0.40 0.01 EPA 440'5-85-031, Baes et al1984 ,_ Beeflro"------- ------------ - --O:ij025 0.02 BOhnetal1979, Baesetal1984 ' BEier---Lead ------- ------45 -0.045 -- -0.0003 EPA-44Q-'-5--a4-027, Baes et a11984 ----------- Beel-Manganese 0.0125---4-.-00E-04 Bohn et a11979, Baes et al1984 - BeefMercury -- 4994 0.9 0.25 EPA 440/5-84-026, Baes et al1984 BeefSelenium -- - --0.025 ---0.015 Bae'-et a11984 BeefSilv-e-r------ ------ 11 ----0.4 --0_-003 EPA 440/5-871011, Baes et al1984 - 8ee"(--,---- -------r---- -- ------- - -------f------ --- - ~c.--.-

i;';"allium___ 34 O.()~ 0.04 Will and Suter 1994, Baes et al1984 __ I3~",f__Vanadium 0_0055 0.025 Baes et a11984 BeefZin-c--------- ----- - ---- --c{-S------O.1 Baes et al1984 - -- Beel--

'-Be-n-z-oldef]phenanthrenel 4.88 2691 0.00 2.0E-03 M-ack-ay-1982, Travis-& Arms 1988--Seef--Bis(2-elhylhexyl) phthaTa---- 5.11 ---886 - ---0.043 - 0_02 Will &-Suter1994, Mayer 1976, Garlen &Trabalka 19 rodents----- ------- --- ------ ----- -.~ --- ---- - , ----r-.---~n-buty~J)Ilthala~-----_ 4.5 lSll1 0.10 ~.(Jl Garlen _& Trabalka 1!!83 __ rodents _'l_-M_elt1~na~hthale_n_e_ ._4,-~ 61 l1 0,1!) 3._2§:-(J4 T,-a_v_is_&.~rms 1988 Bel!f__()ibenzofuran __4,12 134~ , .o,2~ _:l.:3E-04 Veith et",- 1979, Travis &Arms 1988 Beefalpha-Chlordane 6.0 38019 0.0 0.35 Mackay 1982, Garlen &Trabalka 1983 rodenlsgllmma---C-hl-ordane--- - 60 '--38019 ---0:0 - --0-_3-5 Mi,cl<ay-1982,Garl-e-n-&Trabalka 1983 -- -7.xtents-PCS1260---- ------- - -6-_91 -194000 - - -0:6 - - --0-.2-5 Veilhe-t-a-II-97-9,T-ra-vi-s&-A-rm-'-1988 Beef--4,4'-DDO---------- --4_92 - -831766:"1 - --. -4_5 Garten &Trabalka-1983 - rodeiilS-,------ -------- - - ---- -- ------- --- ---- - --------- -- --- ----- -,--------4,4'-DDE 5_69 51286 0.02 10_7 Mackay 1982, Garlen &Trabalka 1983 rodents4,4'-D5T---- -- -5:73---31623 0_02 -- 2.5- Travis &Arms 198iCGa~en & Trabalka 1983 rodellls------------ ---- -----,----- ----- -- - --- ----- - ---- --------- --- ---- ----

~1-D'--cJ:1I<l.roelhylenel-l,-_~,!~___2~_.'l~ 2.9E-OO WIII~ Suter I~Jravis & Arms 1988 _ Bee_f _.t..!,!-Trichloroeth"n_e ....'l~~ _,. ~, 'j,' ,..tA, _, __ 6.9E-OO W."! & Suter 1994, Travis & Arms 1988 _ Beef~_h~romethane (J,9_1 . 0,~9 __11,5 ,1.6E-07 Travis & Arms 1988 BeefCarbon disulfide 5 4800 0_8 2.7E-03 Travis & Arms 1988, JAYOR 1996 Beef

3/19/98

model coet.xls

terrestrial effects

DESCRIPTIO Mouse Crijerion Concentration Units Reference-_._._.__...._.- .. _------_._---_._- -- ... - -- ._---- ._-.~--------

1,3,5-Trinitrobenzene NOAEL - P. leucopus 57.4 mglkg/d Reddy et al1gg5 cited------.. -.-- - ..-. --.-- ... -. --- . -- -.- - - ---C~ -.- - ----------.-----.

!,_3-_D_in_itr_ob_e_nz_e_n,,-_ N.9A~L - rat_. _ .._ I. _..Cl2..3.l11glkg/d !~Image and Opresko~6--Dinitrotolu-"n_e_._ take." ~s 2,4i~ome,-_. .. _. _~ mglkg/d~,4-Dinitrotoluene NOEL - mouse 13.5 mglkg/d USACE 19962,4,6--Trinitrotoluene 1a NoAEI::P.leucopus--··--- -.--- ---3 mQlkg/d Talmage-and Opreskol_ ....-.-.---.--... .. - .-----.--- --- -----~~-.---=-c----··-··-·---Tetryll N-Methyl-N,2,4,6 NOAEL - P. leucopus 2.4 mgikg/d Talmage et al1996Cyclotelr,imelhylenetetra NOEl-rat---- - ---- ---- .-....-- .. ----·115 mgikg/d USACE 1996 - .--~~~~~--'-"-.---_._----_._.._. ----- ..._--RDX 1Cyclonite 1Hexahy NOAEL - mouse 7.9 mgikg/d Talmage et al1996Aluminum-= N6A~L_~~~TeuCoPll~~=~-=-__ · - __.. 2.086 mgtk~~~am.Ple et a11996Barium NOAEL - P. leucopus 10.80 mglkg/d Sample et a11996Be-ry-lIiu-m----·--·-·-- -N-OA-EL ·-P-.-Ie-ucopus ...-..-----.- -----i-:-32mgtkgld Sample et a11996

Ig:~:~ium:::------ .. ~6AEL(c:r,,:61~~:Teucapus.....:........ ---6.55 mgiJ(gi<i Sample et al1900-

Copper NOAEL - P. leucopus -. 30.4 mgikg/d Sample et a11996---- .... -- -.- ..-----.----- - ..- - ---- -'=1-=-'''--_·_-·_··---Iron NOAEL -lab rat 147 mgikg/d Shah & Belone (1991)- -.-------.-. --.. - - -.--- ---.. -.---..-.- - - f--------- - ---"'''' =_.

Lead NOAEL - P.leuc.."!'.us__ _ .._ 15.98 mgikg/d Sample et a11996Manganese __ NOAEL - P. leuc0.PlIs. ... ___ 176 mglkg/d Sample et al 1996Mercury NOAEL - P. leucopus (as Me-Hg) 0.064 mglkg/d Sample et a11996------ -. ---.-- ---1----- .-S_e_le_ni_um ._ _ __ !'J()I\EL :.£'.:...I,,-u_cop.us __ ___.__. 0.3~~ mglkg/d Sample et a11996_S_i1ver .. L_O_A.~l:..:_f':leu<:<>pu .. ()~1.~i_"'_9Ikg/d IRIS _:r..hal"-urn ~()-AE-L---P-.I-e-ucopus _ ......... .. 0.015 mglkgld Sample et a11996I/~nadium _. N()I\IOL.,:I'·le-'JC<lPll~ _ _._. __ ._ ... 0.3il.!lf"'lLIkJ!/cl S~l11flle-"t.a!_1~!J6 ,~_. . ~AEL- P.leucopll.s.___ 319.5 mglkg/d Sample etal1996 _Benzo[def]phenanthrene 1 NOAEL - lab mouse 75 mglkgld IRIS-Bi-s(2:elhyl-he-xyl)-p-h-th-al8 NOAET~P.leu60pu-s---- -.-----.. ---"---19-.8 mglkgid sarnpie et a11996 I----.- ... --.---- ~.o------ .-. ------ - ---- ---- ·---~c----f=---'-.Di-n-butyl phthalate NOAEL - P. leucopus 594 mg/kg/d Sample et al 19962:M"-t~i1~~hthaT_,,n_e_'-_-: ~()'Io.ot~n_ihra~iie_NO_-A_E_[~lab rnaus -~:::.-=----_-1_0_0 r;,~lkgl~ ,,=R...'S___ 1~-"n_z_o!llr~,, N.QAE_L_-_P, leuc:ollus______ 0.O()O_3_21llll"<~1cl.~~mpleet al_1_9!J6_'alpha-Chlordane NOAEL - P. leucopus 5.0 mglkg/d Sample et a11996---- ..... ---- -.-- -------.... - .. -- ------- ------... -- -.-----r.o----------gaml11a::Chlordane ._. t-I.()I\~..L..~I',--,,,-uC:Oflus_ _ __..__.. 5~0 111l!.1kJ!1d.~l11ple et a11996 IF'c:B_12~0 ._ Iol()AELJ.g~-P~leucopus . 0:061. I11g/1<g.tet ~m'p!e_et a119964,4'-DDD NOAEL - P. leucopus 1.6 mg/kg/d Sample et a119964,4'-IJDE----· NO.A.El - P. leucopus-. .'·--1.6 rng/kgi<i s,"iipje et ,,11900-·4;4'-00f------ NGAEL- p.l"u-copu"·---1.-6 mgtkllld'SimpieetaI1996--- -.-..- ... - ---- - - -.- - . ------- -- --.-- - - ---- -- ---~c~"CO --.-----..-

~c1:Dichlo'-o..thylene_'_1, Iol0A~L_:f':.leucoPIJS_ __ .._. __59.9 1119lkg/d Sample et a11996_1,_1,_1-Trichloroet~anEl_ N()AIOL..: f" le.ucoPlls______ __1_123 mglkg/d Sample et al 1996~I()ro.methane-- t'l()AEL...-F'cleuC()l'.us____ _. 11'~l11gik~1cl Sample et a11996Carbon disulfide NOEL - lab rats & rabbits 11 mglkg/d IRIS

3/19/98

terrestrial effects

142.7

1.78.6

3.93.2151

10.4

Reference I,,!uteo NOAEL(m_g/kg_'~+~X()tis NOAEL: (mglkg/cl75

'+_ -+-- 0.30c- --+- __+_ _~

18

1----------- ,- ,

---------

-------------- ---'-------

Concentration I Units

.-

f:!~~~~~t~-~:-".El'-~~::I~agleCriterion

---------.----_ .."-_ ....__.----~,-6--0-i-nitrot()lu-el1e----~2,4-0initrotoluene2.4.6-Tri':'itrOiolu~e I ani'996 ---!e~ry'-'-N-M_ethyl-N,2,4,6

<;¥~()tet",methylenetetra

~ROX I C¥clonite I HexahY\. --+1__Aluminum

-~-----,

Barium

Bery~iurn ----=t=-=-.---- == t==--Chromium~o~a~------- -+ _Copper 40Ifo-n-------'-------f------------ -------- ----------,----- -,-- 193[ea(l--------- --- ---------- ---------- ------21-------,-" ----- -- --- -----------J-------~~Manganese 231Mercury _n_ NOEAL _bald eagle -_. 0,19803 mglkg/d derived from Sampl 0.45000 ,- 0,084Selenium - ,.- ------' 0,52sfiv,,-r-~" ,-- ------ ----- ,----,- ----------- --- ---- ----- - - --- --0:14fhallium---- ----~-- -- -------------- 0,020------------ -------,-,--,-,- -",-- - -- ,--,-, --+-----Vanadium 0.51linc ----------- ------- -,. ------420------------- ---------- ------- ,- --- -------- -"-"----------f--------~

"!en_z_o~e_f]_ph'!r1anthrenE!_' __ _ _, _ _ -1____ 98Bis(2-ethylhexyl) phthala 26[)i:-n~buiYrptiihalate= __ , ;_=.:..: -=___ ____-= =_=--= =_____________7802-Methylnaphthalene 131--,,-- ------ -.. -"---~~---------"'-"" - -, -----------f--------------"-o~--,---,--~~~

[)i~nz_oflJ"'_n ~OJ._o_fra-,--N()I\§,.:.~aldeaglE!_ __OeOOOOO!) mglkg/d deriv<od!rom Sampl 0.OO<!012 __.Q._OO_lJ'I~

alpha-Chlordane NOEAL - bald eagle 0.4145 mglkg/d derived from Wiema 0.5862 6.6ganima:Chlordan~__ ~()EAL :J>ald-""gf"=== ;:-~~41~~ riig/k.g/d deri-"ti<lt'rom=~"ma 0.5862 ---fl~

PCB.E60 ._, __ Ngf:I\!-_~~,,~deagle__ _0.1266 mglkg/d clE!ri_vl!dfrom_~amlll 0.1791 0.0804,4'-000 NOEAL - bald ea91e 0.0030 mglkg/d Sample et al 1996 0.0030 2.14,4'-DbE-- ----- - NOEAC-=-bald eagi" - -- --- -0.0030 mg/kg/d Sample et al 1996 - --- ------- 0.0030 -----------2.14,4'-DOT---' ---- NOEAL-=t)ald "agl,,--- ---0.01l30 nigJkgid s"niple-el 311900- ------- -0.0030 --- 2.11,1--0-i-ch-lo-ro-eiii-yl-en-e7C---------------- --------, - ..- ------------- '" . -----------7-9'1.Tl~frichlc;roejhane-- .-------------f-------.-- -- --- ----- '--14-7-5Chlor."rnethane __-=---= =_= _-_'.---___ _ .------- --15.4Carbon disulfide 14.4

modeLcoef.xls 3/19/98

mode' ....,el.xls

ParameterBody weight (kg)Food intake (kglkg-d)Water intake (kglkg-d)Soil intake (portion 01 diet)

OilllTerrestrial invertebratesVegetationFishMammalsBirdsAquatic invertebrates

Exposure modification rate

Standard animals

Shrew Vole Mouse Eagle Mallard Bat Hawk0.015 0.044 0.022 4 1.1 0.0074

0.6 0.11 0.15 0.12 0.51 0.34 0.10.22 0.14 0.04 0.036 0.057 0.0570.08 0.024 0.02 0.02 0.02 0.02

0.786 0.03 0.214 0.7 00.214 0.97 0.786 0.3

0.7670.068 10.165

1

1 0.05 0.4 1 1

3/19/98

risk.xls

COEC1,3,5-Trinitrobenzene2,4,6-Trinitrotoluene 1aCyclotetramethylenetetranRDX 1Cyclonite 1HexahydTetryll N-Methyl-N,2,4,6AluminumChromiumIronLeadMercurySilverThalliumBariumBerylliumSeleniumZincCobaltManganeseVanadiumBenzo[defjphenanthrene 1Chloromethane4,4'-DDE4,4'-DDT

Brush - aquatic

Surface WaterExposure Point Concentrations (ug/L) RTV

5.993 12058.926 13051.296 3300

248.428 49001.793 3000

50 328814.874 68

700 130021.64 18.880.189 120

5 0.3620.531 12

76 43.06 57

1.938 88.35 605 23

30 1205 20

2.131 20001.885 2200

o 0.013o 0.013

Hazard Quotients0.050.5

0.020.05

0.0010.020.20.51.1

0.002141.719

0.050.020.080.220.250.3

0.0010.0009

0.00.0

Page 1

3/19/98

Brush - terrestrial Page 1

Measured Concentrations in Soils (uglkg) Exposure Concentrations in Soils (ug/kg) Concentrations in Water Concentrations in Vegetation (uglkg)COEC Be9 BC10 BC3 BC6 BC9 BC10 BC3 Watershed Brush Creek (ugll) BC9 BC10 BC3 watershed

1,3,5-Trinitrobenzene <312 <312 <312 <312 244 4680 244 1210 5.993 1965 37688 1964.9 9746.92,4,6-Trinitrotoluene I a <314 <314 1300 <314 228 45000 228 27106 58.926 0.0 4.5 0.0 2.711Cyctotetramethylenetetran <285 610 2300 <285 143 610 2300 11232 51.296 399 1,708 6440 31449RDX I Cyclonite I Hexahyd <273 920 4700 <273 137 920 4700 14229 248 1502 10,120 51700 156519Tetryl f N-Methyl-N,2,4,6 <286 <286 <286 <286 366 366 366 466 1.793 439 439 439 560Aluminum 16315998 12100000 2800000 10555963 50 11584 8591 1988 7495Chromium 11200 16000 26800 10200 21767 145000 90600 37810 14.874 163 1088 680 284Iron 19264200 37500000 7370000 18588894 700 48160 93750 18425 46472lead 15400 18300 18000 9600 28586 27000 21500 206283 21.64 1286 1215 968 9283Mercury <120 <120 <120 <120 25 140 494 446 0.189 22.5 126 445 402Silver 790 1200 2800 2100 790 1200 2800 569 5 316 480 1120 228Thallium <3700 <3500 <3600 <3600 1850 1750 1800 18321 20.531 7.4 7.0 7.2 73Benzoldef]phenanthrene I 17 17 968 2.131 0.97 0 1.0 57Bls(2-ethylhexyl) phthala 1000 310 1126 0 43 0 13.4 49Di-n-butyl phthalate 31 31 554 0 3.0 0 3.0 54Dibenzofuran 18 18 119 0 2.8 0 2.8 194,4'-000 <0.68 <0.65 <0.67 <0.66 4 0.325 0.335 794 0 0.22 0.018 0.019 444,4'-00E <0.68 <0.65 <0.67 <0.66 4 0.325 0.335 2007 0 0.08 0.006 0.007 404,4'-00T <0.64 <0.61 <0.63 <0.62 4 0.305 0.315 267 0 0.08 0.006 0.006 5.0alpha-Chlordane <1.4 <1.3 <1.3 <1.3 0.7 0.7 0.7 880000 0 0.01 0.009 0.009 11601gamma-Chlordane <1.4 <1.3 <1.3 <1.3 0.7 0.7 0.7 640000 0 0.01 0.009 0.009 8437PCB 1260 <6.7 <6.4 <6.7 <6.5 40 3.2 3.35 2398 0 0.16 0.013 0.013 9.4

risk.xls 3/19/98

COEC1,3,5-Trinitrobenzene2,4,~Trinitrotoluene I aCyclotetrarnethylenetetranROX I Cyclonne I HexahydTetryll N-Melhyl-N,2,4,6AluminumChromiumIronLeadMercurySilverThalliumBenzo{def)phenanthrene IBis(2-ethylhexyl) phthalaDi-n-butyl phthalateDibenzofuran4,4'-0004,4'-00E4,4'-00Talpha-ehlordanegamma-ehlordanePCB 1260

risk.xls

Mouse Dose - Vegetation (mglkg/d)Beg BC10 BC3 Watershed

2.4E-Ql 4.6E+OO 2.4E-Ql l.2E+OO2.8E-Q6 5.5E-Q4 2.8E-Q6 3.3E-Q44.8E-Q2 2.1E-Ql 7.8E-Ql 3.8E+OO1.8E-Ql 1.2E+OO 6.3E+OO 1.9E+Ol5.3E-Q2 5.3E-Q2 5.3E-Q2 6.8E-Q21.4E+OO 1.0E+OO 2.4E-Ql 9.1E-Ql2.0E-Q2 1.3E-Q1 8.3E-Q2 3.4E-Q25.9E+OO 1.lE+Ol 2.2E+OO 5.6E+OO1.6E-Ql 1.5E-Ql 1.2E-Ql 1.1E+OO2.7E-Q3 1.5E-Q2 5.4E-Q2 4.9E-Q23.8E-Q2 5.8E-Q2 1.4E-Ql 2.8E-Q29.0E-Q4 8.5E-Q4 8.7E-Q4 8.9E-Q31.2E-Q4 0 1.2E-Q4 6.9E-Q35.2E-Q3 0 1.6E-Q3 5.9E-Q33.6E-Q4 0 3.6E-Q4 6.5E-Q33.4E-Q4 0 3.4E-Q4 2.3E-Q32.7E-Q5 0 0 5.4E-Q39.7E-Q6 0 0 09.2E-Q6 0 0 6.1E-Q4

o 0 0 1o 0 0 1.0E+OO

1.9E-Q5 0 0 1.lE-Q3

Brush - terrestrial

Mouse Dose -Invertebrates (mglkg/d)BC9 BC10 BC3 Watershed2.E-DB 4.E-Q7 2.E-DB 1.E-071.E-Q9 2.E-Q7 1.E-Q9 1.E-Q75.E-l0 2.E-09 7.E-Q9 4.E-DB3.E-Q6 2.E-Q5 1.E-Q4 3.E-Q41.E-Q8 1.E-DB 1.E-DB 2.E-DB6.E-Q4 4.E-Q4 1.E-Q4 4.E-Q43.E-Q5 2.E-Q4 1.E-Q4 5.E-Q53.E-Q2 6.E-Q2 1.E-Q2 3.E-Q21.E-Q5 1.E-Q5 1.E-Q5 9.E-Q52.E-Q4 1.E-Q3 4.E-Q3 3.E-Q33.E-Q5 5.E-Q5 1.E-Q4 2.E-Q51.E-Q5 9.E-Q6 1.E-OS 1.E-Q46.E-Q8 0 6.E-DB 4.E-Q62.E-Q5 0 7.E-Q6 3.E-OS1.E-Q6 0 1.E-Q6 2.E-Q53.E-Q8 0 3.E-DB 2.E-Q73.E-Q5 0 0 7.E-Q3

o 0 0 06.E-Q6 0 0 4.E-Q4

o 0 0 0o 0 0 1.E-Ql

1.E-D6 0 0 8.E-Q5

Page 2

Mouse Dose from Soil (mglkgld) Mouse Dose from Water (mglkdld)8C9 BC10 BC3 Watershed BC9 BC10 BC3 Watershed

7.5E-Q4 1.4E-Q2 7.5E-Q4 3.7E-Q3 2.6E-Q4 2.6E-Q4 2.6E-Q4 2.6E-Q47.0E-Q4 1.4E-Ql 7.0E-Q4 8.4E-Q2 2.5E-Q3 2.5E-Q3 2.5E-Q3 2.5E-Q34.4E-Q4 1.9E-Q3 7.1E-Q3 3.5E-Q2 2.2E-Q3 2.2E-Q3 2.2E-Q3 2.2E-Q34.2E-Q4 2.8E-Q3 1.5E-Q2 4.4E-Q2 1.lE-Q2 1.lE-Q2 1.lE-Q2 1.lE-Q21.lE-Q3 1.lE-Q3 1.lE-Q3 1.4E-Q3 7.7E-Q5 7.7E-Q5 7.7E-Q5 7.7E-Q55.0E+Ol 3.7E+Ol 8.7E+OO 3.3E+Ol 2.1E-Q3 2.1E-Q3 2.1E-Q3 2.1E-Q36.7E-Q2 4.5E-Ql 2.8E-Ql 1.2E-Ql 6.4E-Q4 6.4E-Q4 6.4E-Q4 6.4E-Q46.0E+Ol 1.2E+02 2.3E+Ol 5.7E+Ol 3.0E-Q2 3.0E-Q2 3.0E-Q2 3.0E-Q28.8E-Q2 8.3E-Q2 6.6E-Q2 6.4E-Ql 9.2E-Q4 9.2E-Q4 9.2E-Q4 9.2E-Q47.7E-Q5 4.3E-Q4 1.5E-Q3 1.4E-Q3 8.1E-D6 8.1E-Q6 8.1E-Q6 8.1E-Q62.4E-Q3 3.7E-Q3 8.7E-Q3 1.8E-Q3 2.1E-Q4 2.1E-Q4 2.1E-Q4 2.1E-Q45.7E-Q3 5.4E-Q3 5.6E-Q3 5.7E-Q2 8.8E-Q4 8.8E-Q4 8.8E-Q4 8.8E-Q45.1E-Q5 O.OE+OO 5.1E-Q5 3.0E-Q3 9.1E-Q5 9.1E-Q5 9.1E-Q5 9.1E-Q53.1E-Q3 O.OE+OO 9.6E-04 3.5E-Q3 O.OE+OO O.OE+OO O.OE+OO O.OE+OO9.4E-Q5 O.OE+OO 9.4E-Q5 1.7E-Q3 O.OE+OO O.OE+OO O.OE+OO O.OE+OO5.4E-Q5 O.OE+OO 5.4E-Q5 3.7E-Q4 O.OE+OO O.OE+OO O.OE+OO O.OE+OO1.2E-Q5 1.0E-Q6 1.0E-Q6 2.5E-Q3 O.OE+OO O.OE+OO O.OE+OO O.OE+OO1.2E-Q5 1.0E-Q6 1.0E-Q6 6.2E-Q3 O.OE+OO O.OE+OO O.OE+OO O.OE+OO1.2E-Q5 9.4E-Q7 9.7E-Q7 8.3E-Q4 O.OE+OO O.OE+OO O.OE+OO O.OE+OO2.2E-Q6 2.0E-Q6 2.0E-Q6 2.7E+OO O.OE+OO O.OE+OO O.OE+OO O.OE+OO2.2E-Q6 2.0E-Q6 2.0E-Q6 2.0E+OO O.OE+OO O.OE+OO O.OE+OO O.OE+OO1.2E-Q4 9.9E-Q6 1.0E-Q5 7.4E-Q3 O.OE+OO O.OE+OO O.OE+OO O.OE+OO

3/19/98

0.000004oo3סס0.0

oo1סס0.0

oo1סס0.0

oo1סס0.0

0.0002

risk.lds

COEC1,3,5-Trinitrobenzene2,4,6--Trinitrotoluene I aCyclotetramethytenetetranRDX I Cyclonite I HexahydTetryll N-Methyl-N,2,4,6AluminumChromiumIronLeadMercurySilverThalliumBenzo[de~phenanthrene 1Bis(2-ethylhexyl) phthalaDi-n-butyl phthalateDlbenzofuran4,4'-0004,4'-00E4,4'-00Talpha-Chlordanegamma-ChlordanePCB 1260

Brush - terrestrial

Total Mouse Dose (mglkgld) MouseBe9 BC10 Be3 Watershed NOAEL (mgl1<g/d)

2.4E-Ql 4.6E+00 2.4E-Ql 1.2E+00 57.403.2E-03 1.4E-Ql 3.2E-03 8.7E-Q2 3.005.1E-Q2 2.1E-Q1 7.9E-Ql 3.9E+00 1151.9E-Ql 1.2E+00 6.3E+00 1.9E+Ol 7.95.4E-Q2 5.4E-Q2 5.4E-Q2 7.0E-Q2 2.40

5.2E+Ol 3.8E+01 8.9E+00 3.4E+Ol 2.098.8E-Q2 5.8E-Q1 3.6E-Ql 1.5E-Ql 6.55

6.5E+Ol 1.3E+02 2.5E+Ol 6.3E+Ol 1472.5E-Ql 2.3E-Ql 1.8E-Ql 1.8E+00 16.03.0E-03 1.7E-Q2 5.9E-Q2 5.4E-Q2 0.064.1E-Q2 6.2E-Q2 1.5E-Ql 3.0E-Q2 0.117.5E-03 7.1E-Q3 7.3E-03 6.7E-Q2 0.022.6E-04 9.1E-05 2.6E-04 1.0E-Q2 758.3E-Q3 O.OE+oo 2.6E-Q3 9.4E-03 204.5E-04 O.OE+oo 4.5E-Q4 8.3E-Q3 5944.0E-04 O.OE+OO 4.0E-04 2.7E-03 0.00037.2E-05 5.9E-06 6.0E-06 1.4E-02 1.605.0E-05 4.1E-06 4.2E-06 2.5E-Q2 1.62.8E-05 2.1E-06 2.2E-06 1.8E-03 1.63.4E-06 3.1E-06 3.1E-06 4.3E+00 5.03.4E-06 3.1E-06 3.1E-06 3.1E+00 5.01.4E-Q4 1.2E-05 1.2E-05 8.6E-Q3 0.1

BC90.0040.001

0.00040.020.02

250.01

0.40.020.05

0.40.5

oo3סס0.0

0.00040.0000008

1.20.00005OO3סס.0

OO2סס.0

oo1סס0.0

oo1סס0.0

0.002

Hazard QuottentsBC10 BC3 Watershed

0.08 0.004 0.020.05 0.0011 0.03

0.002 0.007 0.030.18 0.8 2.40.02 0.02 0.03

18 4.3 180.09 0.06 0.02

0.9 0.2 0.40.01 0.01 0.1

0.3 0.9 0.80.6 1.4 0

0.5 0.5 4oo1סס0.0 oo3סס0.0 0.0001

0.0001 0.0005oo1סס0.0 OO1סס.0

1.2 80.000004 0.0090.000003 0.02oo1סס0.0 0.001oo1סס0.0 0.90,0000006 0.6

0.0002 0.1

Page 3

3/19/98

risk.xls

Brush - terrestrial

Concentration in Mammals (uglkg) Concentratton in Fish (uglkg) Concentration in Birds (uglkg) Concentration In SoH (ugl1<g)COEC BC9 BC10 BC3 BC6 BC9 BC10 BC3 BCG BC9 BC10 BC3 Be6 Be9 Bel0 BC3 BCG

1,3,5-Trinftrobenzene2,4,6-Trinitrotoluene I aCyclotetramethylenetetranRDX I Cyclonite I HexahydTetryt I N-Methyl-N,2,4,6AluminumChromiumIronLeadMercury <100 <100 <100 <100 250 6 32 111 100 <120 <120 <120 <120SilverThalliumBenzo[de~phenanthrene IBis(2-ethylhexyl) phthalaDi-n-butyl phthalateDibenzofuran4,4'-000 <1.7 <1.7 <1.7 <1.7 0<1.7 <1.7 1.0 0.1 0.1 <0.68 <0.65 <0.67 <0.664,4'-00E <1.7 <1.7 <1.7 <1.7 0<1.7 <1.7 0.9 0.1 0.1 <0.68 <0.65 <0.67 <0.664,4'-00T <1.6 <1.6 <1.6 <1.6 0<1.6 <1.6 0.2 0.0 0.0 <0.64 <0.61 <0.63 <0.62alpha-Chlordane <3.3 <3.3 <3.3 <3.3 0<3.3 <3.3 <1.4 <1.3 <1.3 <1.3gamma-Chlordane <3.3 <3.3 <3.3 <3.3 0<3.3 <3.3 <1.4 <1.3 <1.3 <1.3PCB 1260 <16.4 <16.4 <16.4 <16.4 a <16.4 <16.4 0.0 0.0 0.0 <6.7 <6.4 <6.7 <6.5

Page 4

3/19/98

Brush - terrestrial Page 5

Bald Eagle Dose Estimates (mglkg/d)BC9-0iet BClO-0iet BC3-0iel BC6-0iet BC9-Soil BCIO-Soil BC3-Soil BCG-Soil BC9-Total BelO-Total Be3-Total BC6-Total

0.00001 0.00000o 0.00000 0.0000043 0.0000008 0.0000008 0.0000008 0.0000008 0.00001 0.0000012 0.00001 0.000010.00001 0.00000o 0.00000 0.0000043 0.0000008 0.0000008 0.0000008 0.0000008 0.00001 0.0000010 0.00001 0.000010.00000 0.00000o 0.00000 0.0000043 0.0000008 0.0000007 0.0000008 0.0000007 0.00000 0.0000009 0.000005 0.000010.00001 0.00000o 0.00001 0.00001 0.000002 0.000002 0.000002 0.000002 0.00001 0.0000016 0.00001 0.000010.00001 0.00000o 0.00001 0.00001 0.000002 0.000002 0.000002 0.000002 0.00001 0.0000016 0.00001 0.000010.00004 0.00000o 0.00004 0.00004 0.000008 0.000008 0.000008 0.000008 0.00005 0.000008 0.00005 0.00005

rlsk.xls

COEC1,3,5-Trinitrobenzene2,4,6-Trinitrotoluene I aCyclotetramethylenetetranROX I Cyclon~e I HexahydTetry! I N-Methyl-N,2,4,6AluminumChromiumIronLeadMercurySilverThalliumBenzo[def)phenanthrene IBis(2-ethylhexyl) phthalaOi-n-butyl phthalateDbenzofuran4,4'-0004,4'-00E4,4'-00Talpha-ehlordanegamma-ChlordanePCB 1260

0.0000 0.0001 0.0004 0.0021 0.000144 0.000144 0.000144 0.000144 0.00017 0.00024 0.00050 0.00221

3/19/98

risk.xls

Brush - terrestrial

Bald Eagle Hazard QuotientsCOEC NOAEL (mglkg/d) BC9 BC10 BC3 BC6

1,3,5-Trinitrobenzene2,4,6-Trinitrotoluene I aCyclotetramethylenetetranRDX I Cyclonite I HexahydTetryll N-Methyl-N,2,4,6AluminumChromiumIronLeadMercury 0.19803 0.001 0.001 0.003 0.01SilverThalliumBenzo[def]phenanthrene IBis(2-ethylhexyl) phthalaOi-n-butyl phthalateDibenzoruran4,4'-000 0.0030 0.0020 0.00042 0.0017 0.00174,4'-00E 0.0030 0.0020 0.00033 0.0017 0.00174,4'-00T 0.0030 0.0017 0.00029 0.0016 0.0017alpha-Chlordane 0,4145 0.00002 0.000004 0.00002 0.00002gamma-Chlordane 0.4145 0.00002 0.000004 0.00002 0.00002PCB 1260 0.1266 0.0004 0.00006 0.0004 0.0004

Page 6

3/19/98

risk.xis

COECAluminumIronLeadThalliumBariumBerylliumMercurySeleniumZincCobaltManganeseVanadiumBenzo[def]phenanthrene 1alpha-Chlordanegamma-Chlordane4,4'-DDE4,4'-DDT1, l-Dichloroethylene 11 ,

Long - aquatic


50 328850 1300

4.174 18.887.387 12

130 42.676 570.126 1202.134 88.3

44 605 23

31 1205 20

1.4 2000o 1.6o 1.6o 0.013o 0.013

0.601 25

Hazard Quotients0.020.040.2

0.6233

0.050.001

0.020.730.220.260.250.000.000.000.000.000.02

Page 1

3/19/98

Long - terrestrial Page 1

risk.xfl':

Measured COEC (uglkg Exposure Concentrations - Soils (uglkg) Concentrations in Waler Concentrations in Vegetation (uglkg)COEC LCl LC2 LCl LC2 Long Creek (ugll) LCl LC21,3,5-Trin~robenzene <312 <312 156 1045 0 1256.3 8415.42,4,6-Trin~rotoluene / a <314 <314 3142 960 0 0.3 0.1ROX / Cyclon~e / Hexahyd <273 <273 137 137 2 1502 1502Cyclotetramethylenetetran <285 <285 143 635 399 17782,4-0in~rotoluene <316 <316 70 210 0 0 0Aluminum 14744156 0 50 10468 0Chromium 3200 7600 20061 35800 0 150.46 268.50Iron 20379626 0 50 50949 0.0Lead 6400 16900 25352 19000 4.17 1140.8 855.00Silver <520 <610 295 402 5 117.80 160.60Thallium <3100 <3600 1550 1800 7.39 6.2 7.20Benzo[def]phenanthrene / 17 0 1.4 0.97 0.0Bis(2-ethylhexyl) phthala 310 0 0 13.4 0.0Di-n-butyl phthalate 31 0 0 3.0 0.0alpha-Chlordane <1.1 <1.3 0.55 0.65 0.007 0.014,4'-00E <0.58 33 12 33 0.2 0.74,4'-00T <0.54 <0.63 16 0.315 0.3 0.006gamma-Chlordane <1.1 <1.3 0.55 0.65 0 0.01 0.0091,1,1-Trichloroethane 2 1 2.8 0.0

3/19/98


Mouse Dose - Vegetation (mglkg/d) Mouse Dose - Invertebrates (mglkg/d) Mouse Dose - Soil (mglkg/d) Mouse Dose - Water (mglkg/d)COEC LC1 LC2 LC1 LC2 LC1 LC2 LC1 LC21,3,5-Trinttrobenzene 2.E-01 1.E+OO 1.E-08 8.E-08 5E-04 3E-03 OE+OO OE+OO2,4,6-Trinttrotoluene 1a 4.E-05 1.E-05 1.E-08 4.E-09 1E-02 3E-03 OE+OO OE+OORDX 1Cyclontte 1Hexahyd 2.E-01 2.E-01 3.E-06 3.E-06 4E-04 4E-04 9E-05 9E-05Cyclotetramethylenetetran 5.E-02 2.E-01 5.E-10 2.E-09 4E-04 2E-03 OE+OO OE+OO2,4-Dinttrotoluene 9.E-07 3.E-06 7.E-10 2.E-09 2E-04 6E-04 OE+OO OE+OOAluminum 1.E+OO O.E+OO 5.E-04 O.E+OO 5E+01 OE+OO 2E-03 2E-03Chromium 2.E-C2 3.E-02 3.E-05 5.E-05 6E-02 1E-01 OE+OO OE+OOIron B.E+OO O.E+OO 3.E-02 O.E+OO BE+01 OE+OO 2E-03 2E-03Lead 1.E-01 1.E-01 1.E-05 8.E-OB 8E-02 BE-02 2E-04 2E-04Silver 1.E-02 2.E-02 1.E-05 2.E-05 9E-04 1E-03 2E-04 2E-04Thallium 8.E-04 9.E-04 8.E-OB 1.E-05 5E-03 BE-03 3E-04 3E-04Benzo[def]phenanthrene 1 1.E-04 O.E+OO 6.E-08 O.E+OO 5E-05 OE+OO BE-05 6E-05Bis(2-ethylhexyl) phthala 2.E-03 O.E+OO 7.E-OB O.E+OO 1E-03 OE+OO OE+OO OE+OODi-n-butyl phthalate 4.E-04 O.E+OO 1.E-06 O.E+OO 9E-05 OE+OO OE+OO OE+OOalpha-Chlordane 9.E-07 1.E-06 8.E-08 1.E-07 2E-OB 2E-06 OE+OO OE+OO4,4'-DDE 3.E-05 8.E-05 8.E-05 2.E-04 4E-05 1E-04 OE+OO OE+OO4,4'-DDT 4.E-05 7.E-07 2.E-05 5.E-07 5E-05 1E-06 OE+OO OE+OOgamma-Chlordane 9.E-07 1.E-06 8.E-08 1.E-07 2E-06 2E-OB OE+OO OE+OO1,1,1-Trichloroethane 3.E-04 O.E+OO B.E-10 O.E+OO BE-OB OE+OO 4E-05 4E-05

risk.x1s 3/19/98

risk.xis

Long - terrestrial

Total Mouse Dose (mglkg/d) Mouse Hazard QuotientsCOEC LC1 LC2 NOAEL (mglkg/d) LC1 LC21,3,5-Trin~robenzene 2E-01 1E+00 57.40 0.003 0.022,4,6-Trin~rotoluene1a 1E-02 3E-03 3.00 0.003 0.001RDX 1Cyclon~e 1Hexahyd 2E-01 2E-01 7.90 0.02 0.02Cyclotetramethylenetetran 5E-02 2E-01 115.00 0.0004 0.0022,4-Din~rotoluene 2E-04 7E-04 13.5 0.00002 0.00005Aluminum 5E+01 2E-03 209 22 0.001Chromium 8E-02 1E-01 6.55 0.01 0.02Iron 7E+01 2E-03 147 0.5 0.00001Lead 2E-01 2E-01 16.0 0.01 0.01Silver 2E-02 2E-02 0.11 0.1 0.2Thallium 6E-03 7E-03 0.02 0.4 0.45Benzo[del]phenanthrene 1 2E-04 6E-05 75 0.000003 0.0000008Bis(2-ethylhexyl) phthala 3E-03 OE+OO 19.8 0.0001D~n-butyl phthalate 5E-04 OE+OO 594 0.000001alpha-Chlordane 3E-06 3E-06 5 0.000001 0.0000014,4'-DDE 2E-04 4E-04 1.60 0.0001 0.00034,4'-DDT 1E-04 2E-06 1.60 0.00007 0.000001gamma-Chlordane 3E-06 3E-06 5 0.000001 0.0000011,1,1-Trichloroethane 4E-04 4E-05 1123 0.0000003 0.00000004

Page 3

3/19/98

<3.3 <3.3 0.0 <3.3 0.0 0.00 <1.1 <1.3<1.7 <1.7 0.0 <1.7 2.6 7.04 <0.58 33<1.6 <1.6 0.0 <1.6 0.74 0.01 <0.54 <0.63<3.3 <3.3 0.0 <3.3 0.0 0.00 <1.1 <1.3

COEC1,3,5-Trin~robenzene2,4,6-Trin~rotoluene / aRDX / Cyclon~e / HexahydCyclotetramethytenetetran2,4-Din~rotoluene

AluminumChromiumIronLeadSilverThalHumBenzo[def]phenanthrene /Bis(2-ethythexyl) phthalaD~n-butyt phthalatealpha-Chlordane4,4'-DDE4,4'-DDTgamma-Chlordane1,1,1-Trichloroethane

risk."'s

Concentration in Mammals (uglkg)LC1 LC2

Long - terrestrial

Concentration in Fish (uglkg)LC1 LC2

Concentration in Birds (uglkg)LC1 LC2

Page 4

Concentration in Soil (uglkg)LC1 LC2

3/19/98


Bald Eagle Dose Estimates (mglkg/d) Bald Eagle Hazard QuotientLC2-Diet LC1-Soil LC2-Soil LC1-Total LC2-Total NOAEL (mglkg/d) LC1

risk.xl"

COEC1,3,5-Trinijrobenzene2,4,6-Trinijrotoluene 1aRDX 1Cycionije 1HexahydCyclotetramethylenetetran2,4-DinijrotolueneAluminumChromiumIronLeadSilverThalliumBenzo[del]phenanthrene 1Bis(2-ethylhexyl) phthalaDi-n-butyl phthalatealpha-Chlordane4,4'-DDE4,4'-DDTgamma-Chlordane1,1,1-Trichloroethane

LC1-Diet

0.0000010.00000

0.0000010.000001

0.00001 0.00000007 0.000000080.00001 0.00000003 0.0000040.00000 0.00000003 0.000000040.00001 0.00000007 0.00000008

0.00000074 0.000010.000003 0.000020.000001 0.000005

0.0000007 0.00001

0.41450.00300.00300.4145

0.0000020.000970.00036

0.000002

LC2

0.000020.005200015

0.00002

3/19198

risk.xis

COEC1,3,5-TrinitrobenzeneCyclotetramethylenetetranRDX 1Cyclonite 1HexahydAluminumIronLeadBariumBerylliumCopperSeleniumCobaltManganeseVanadiumBenzo[defjphenanthrene 1

Spring - aquatic


0.299 12016.51 330090.3 4900150 3288190 130025 18.9

110 42.5 57

13.19 3.81.684 88.3

5 2364 120

5 201.4 2000

Hazard Quotients0.0020.0050.020.05

0.11.3

27.50.043.5

0.020.20.50.3

0.0007

Page 1

3/19/98

14100 16600 10700<580 330 <620

3500 <3800 <3700

Measured Concentrations in Soils (ug/kg)SCl SC2 SC4

<312 <312 <312<314 <314 <314<285 <285 <285<273 <273 <273

COEC1,3,5-Trinitrobenzene2,4,6-Trinitrotoluene I aCyclotetramethylenetetranRDX I Cyclonite I HexahydAluminumChromiumIronleadSilverThalliumBenzo[def)phenanthrene IDi-n-butyl phthalate2-Methylnaphthalene

risk.xh

8600 10000 7600

Spring - terrestrial

Exposure Concentrations in Soils (ug/kg)Sel Se2 SC4 Watershed

244 244 156 6873228 228 157 751830333 333 143 3059952294 294 137 842692

15348803 15300000 11730178 1173017820615 22139 7600 47115

21595887 26100000 19122688 1912268820712 52584 10700 233085

295 295 310 12803500 1900 1850 20147

17 17 73 7331 31 566 56625 25 73 73

Concentrations in WaterSpring Creek (ugll)

0.30o

16.590.3150

0.000190

25.0oo

1.40oo

Page 1

Concentrations in Vegetation (uglkg)sel Se2 SC4 Watershed

1965 1965 1256 553450.023 0.023 0.016 75.2

932 932 399 85678673229 3229 1502 7069616

10898 10863 8328 8328155 168 57 353

53990 65250 47807 47807932 2366 481.5 10489118 117.8 124.0 512lU n ~ M0.97 0.97 4.27 4.272.96 2.96 54.95 55.04.00 4.00 11.84 11.8

3119/98

Spring - terrestrial Page 2

risk.xts

COEC1,3,5-Trinitrobenzene2,4,6-Trinitrototuene I aCyclotetramethylenetetranROX' Cyclonite I HexahydAluminumChromiumIronLeadSilverThalliumBenzo[def]phenanthrene IDi-n-butyl phthalate2-Methytnaphthalene

Mouse Dose - Vegetation (mglkg/d)SCI SC2 SC4 Watershed2.4E-<Jl 2.4E-<Jl 1.5E-<Jl 6.7E+OO2.8E-<J6 2.8E-<J6 1.9E-<J6 9.1 E-<J31.lE-<Jl 1.lE-<Jl 4.8E-<J2 1.0E+033.9E-<Jl 3.9E-<Jl 1.8E-<Jl 8.6E+021.3E+OO 1.3E+OO 1.0E+OO 1.0E+OO1.9E-<J2 2.0E-<J2 6.9E-<J3 4.3E-<J2

6.6E+OO 7.9E+OO 5.8E+OO 5.8E+OO1.lE-<Jl 2.9E-<Jl 5.8E-<J2 1.3E+OO1.4E-<J2 l.4E-<J2 1.5E-<J2 6.2E-<J21.7E-<J3 9.2E.{)4 9.0E.{)4 9.8E-<J31.2E.{)4 1.2E.{)4 5.2E.{)4 5.2E.{)43.6E.{)4 3.6E.{)4 6.7E-<J3 6.7E-<J34.9E-<J4 4.9E.{)4 1.4E-<J3 1.4E-<J3

Mouse Dose • Invertebrates (mg/kg/d)SC1 se2 SC4 Watershed2.E-<J8 2.E-<J8 l.E-<J8 6.E-<J71.E-<J9 1.E-<J9 7.E-1O 3.E-<J61.E-<J9 l.E-Q9 5.E-l0 1.E-057.E-<J6 7.E-<J6 3.E-<J6 2.E-<J25.E.{)4 5.E.{)4 4.E.{)4 4.E.{)43.E-05 3.E-<J5 l.E-05 6.E-054.E-<J2 4.E-<J2 3.E-<J2 3.E-<J29.E-<J6 2.E-05 5.E-<J6 1.E.{)41.E-05 I.E-OS 1.E-<J5 5.E-052.E-<J5 1.E-05 l.E-05 1.E.{)46.E-<J8 6.E-<J8 3.E-<J7 3.E-<J7l.E-<J6 l.E-<J6 2.E-05 2.E-054.E-<J8 4.E-<J8 1.E-<J7 1.E-07

Mouse Dose - Soil (mg/kgId)SCI SC2 SC4 Watershed

7.5E.{)4 7.5E.{)4 4.8E-<J4 2.1 E-<J27.0E-Q4 7.0E.Q4 4.9E-Q4 2.3E+OO1.0E-<J3 1.0E-<J3 4.4E-Q4 9.5E+OO9.1E-Q4 9.1E-Q4 4.2E-Q4 2.0E+OO4.7E+Ol 4.7E+Ol 3.6E+Ol 3.6E+016.4E-<J2 6.8E-<J2 2.3E-02 1.5E-<Jl6.7E+01 8.1E+01 5.9E+01 5.9E+016.4E-<J2 1.6E-<Jl 3.3E-<J2 7.2E-<Jl9.1 E-Q4 9.1E-Q4 9.6E-Q4 4.0E-<J31.1E-<J2 5.9E-<J3 5.7E-<J3 6.2E-<J25.1E-05 5.1E-05 2.3E-Q4 2.3E.{)49.4E-05 9.4E-05 1.8E-<J3 1.8E-<J37.6E-05 7.6E-05 2.2E-Q4 2.2E-Q4

3/19198

risk.xl"

Spring - terrestrial

Mouse Dose - Water (mg/kdld) Total Mouse Dose Mouse Hazard QuotientsCOEC SCI SC2 SC4 Watershed SCI SC2 SC4 Watershed NOAEL (m9Ikg/d) SCI SC2 SC4 Watershed

1,3,5-Trinitrobenzene 1.3E-<J5 1.3E-<J5 1.3E-<J5 1.3E-<J5 2.4E.Ql 2.4E.Ql 1.5E.Ql 6.7E+OO 57.4 0.004 0.004 0.003 0.12,4,6-Trinitrotoluene I a OE+OO OE+OO OE+OO O.OE+OO 7.1E.Q4 7.1E.Q4 4.9E-04 2.3E+OO 3.0 0.0002 0.0002 0.0002 0.8Cyclotetramethytenetetran 7.1 E-04 7.1 E-04 7.1 E-04 7.1E-04 1.lE.Ql 1.lE.Ql 5.0E.Q2 1.lE+03 115 0.001 0.001 0.0004 9.1RDX I Cyclonite I Hexahyd 3.9E.03 3.9E.Q3 3.9E.Q3 3.9E.Q3 4.0E.Ql 4.0E.Ql 1.9E.Ql 8.6E+02 7.90 0.05 0.05 0.02 109Aluminum 6.4E.Q3 6.4E.Q3 6.4E.Q3 6.4E.Q3 4.9E+01 4.9E+01 3.7E+01 3.7E+Ol 2.09 23 23 18 18Chromium OE+OO OE+OO OE+OO O.OE+OO 8.3E.Q2 8.9E.Q2 3.0E.Q2 1.9E.Ql 6.55 0.01 0.01 0.005 0.03Iron 8.1E.Q3 8.1E.03 8.1E.Q3 8.1E.03 7.3E+01 8.9E+01 6.5E+01 6.5E+01 147.00 a 1 a aLead 1.lE.Q3 1.lE.03 1.lE.03 1.lE.03 1.8E.Ql 4.5E.Ql 9.3E-02 2.0E+OO 15.98 0.01 0.03 0.006 0.1Sitver OE+OO OE+OO OE+OO O.OE+OO 1.5E.Q2 1.5E.Q2 1.6E.Q2 6.6E.Q2 0.11 0.1 0.1 0.2 0.6Thallium OE+OO OE+OO OE+OO O.OE+OO 1.3E.Q2 6.8E.Q3 6.6E.Q3 7.2E.Q2 0.02 0.8 0.5 0.4 4.8Benzofdef]phenanthrene I 6.0E-<J5 6.0E-<J5 6.0E-<J5 6.0E-<J5 2.3E-04 2.3E-04 8.0E.Q4 8.0E.Q4 75 0.000003 0.000003 0.00001 0.00001Dt-n-butyl phthalate OE+OO OE+OO OE+OO O.OE+OO 4.5E-04 4.5E-04 8.4E.Q3 8.4E.Q3 594 0.000001 0.000001 0.00001 0.000012-Methylnaphthalene OE+OO OE+OO OE+OO O.OE+OO 5.6E-04 5.6E-04 1.7E.Q3 1.7E.Q3 100 0.00001 0.00001 0.00002 0.00002

24.940161 24.605801 142.8925511

Page 3

3/19/98

risk.xls

COECAluminumIronLeadSilverBariumBerylliumCobaltManganeseVanadiumZinc2,4-Dinitrotoluene2,6-Dinitrotoluene1,3,5-Trinitrobenzene1,3-Dinitrobenzene2,4,6-Trinitrotoluene 1aCyclotetramethylenetetranRDX 1Cyclonite 1HexahydCarbon disulfide

Skunk - aquatic

Surface WaterExposure Point Concentrations (ug/L)

2440411

6.0464.965

1162.5

12.5235

11.3721.51

2.250.395

0.570.3065.684

30.8250

17.655

RTV32881300

18.880.36

45723

1202060

620620120370130

330049000.92

Hazard Quotients0.740.320.3213.8

290.040.541.960.570.36

0.0040.0010.005

0.00080.040.010.05

19.19

Page 1

3/19/98

Skunk - terrestrial Page 1

COECRDX 1Cyclonite 1HexahydAluminumChromiumIronLeadSilver4,4'-DDE4,4'-DDT

risk.xfs

Concentration in MediaSoil (ug/kg) Water (ugn) Vegetation (ug/kg) Vegetation

294 250 3234 0.39313,509,471 2,440 9592 1.165

18,735 0 141 0.01706828,830,944 411 72077 8.755

32,000 6.0 1440 0.17492295 5.0 118 0.014309

4 0 0.08 0.00000947 0 0.89 0.000108

Dose Estimates (mglkgld)Invertebrates Soil Waler Total

0.00001 0.001 0.01 0.4040.00048 41.757 0.1 43.0260.00003 0.05791 0.0 0.075000.04768 89.11 0.0 97.930.00001 0.0989 0.0003 0.27410.00001 0.000910 0.0002 0.01540.00003 0.00001 0.0 0.000050.00007 0.00015 0.0 0.00033

Mouse HazardNOAEL (mg/kg/d) Quotient

7.90 0.052.09 216.55 0.01

147.00 0.716.0 0.02o11 0.11.60 0.000031.60 0.0002

21.47

3/19/98

risk.xls

Basewide

Media COEC Concentrations (ug/kg) Buteo Oose Estimates (mglkg/d) NOAELCOEC Soils Vegetation Small Mammals Water Soils Small Mammals Water Total (mg/kg/d) HQMercury 446 402 100 0.189 0.001 0.010 0.00001 0.011 0.45 2.E-Q2Oibenzofuran 119 19 0 o 0.0002 0.000001 0.0 0.0002 1.2E-Q5 2.E+014,4'-000 794 44 197 0 0.002 0.020 0.0 0.021 0.003 7.E+004,4'-00E 2007 40 428 0 0.004 0.043 0.0 0.047 0.003 2.E+014,4'-ODT 267 5 12 0 0.001 0.001 0.0 0.002 0.003 6.E-01alpha-Chlordane 880000 11601 4022 0 1.76 0.40 0.0 2.16 0.59 4.E+00gamma-Chlordane 640000 8437 2925 0 1.28 0.29 0.0 1.57 0.59 3.E+00PCB 1260 2398 9 2 o 0.0048 0.0002 0.0 0.005 0.18 3.E-Q2

3/19/98

risk. xis

PRGs - soil

Soil PRG Vegetation Mouse Dose Estimates (mg/kg/d) Mouse HazardCOEC (ug/kg) log Kow (ug/kg) Vegetation 1nvertebrates Soil Total NOAEL (mg/kg/d) QuotientAntimony 816000 163200 20 0.005 2.5 22 0.13 179Arsenic 30000 1200 0.1 0.00008 0.1 0.2 0.13 2Beryllium 5000 50 0.01 0.000002 0.02 0.02 1.32 0.02Cadmium 1000000 550000 67 0.01 3.1 70 1.85 38Chromium VI 10000000 75000 9 0.01 30.9 40 6.06 7Lead 1000000 45000 5 0.0004 3.1 9 15.98 0.5Thallium 143000 572 0.1 0.0008 0.4 0.5 0.02 34Benzo(a)anthracene 8100 5.61 0.02 0.000003 0.00000001 0.03 0.03 75 0Benzo(a)pyrene 810 6.06 0.01 0.000001 0.00000001 0.003 0.003 1.0 0.003Benzo(b)f1uoranthene 8100 6.54 0.006 0.0000008 0.00000002 0.03 0.03 1.0 0.03Dibenz(a,b)anthracene 810 6 0.01 0.000002 0.00000001 0.003 0.003 1.0 0.003PCB 10000 7 0.003 0.0000004 0.00000004 0.03 0.03 0.06 0.51,3,5-Trinitrobenzene 102000 1.18 821410 100 0.00001 0.3 100 57.40 22,4-Dinitrotoluene 8700 2 0.8700 0.0001 0.0000001 0.03 0.03 13.50 0.0022,4,6-Trinitrotoluene / a 47000 1.46 4.700 0.0006 0.0000002 0.1 0.1 3.00 0.05RDX / Cyclonite / Hexahyd 1000 3.45 11000 1 0.00002 0.003 1.3 7.90 0.2Cyclotetramethylenetetran 51000000 0.26 1.E+08 17,346 0.0002 158 17,504 115.00 152

3/19/98

risk.xis

PRGs - soil

Soil PRG Insect Tissue Bat Dose NOAEL HazardCOEC (uglkg) BCF BAF (uglkg) (mg/kg/d) (mglkg/d) QuotientAntimony 816000 16 16 13056 4 0.177 25Arsenic 30000 9 9 270 0.09 0.178 0.5Beryllium 5000 100 100 500 0.17 1.73 0.1Cadmium 1000000 90 90 90000 30 2.52 12Chromium VI 10000000 3 3 30000 10 8.57 1.2Lead 1000000 45 45 45000 15 21 0.7Thallium 143000 34 34 4862 2 0.020 83Benzo(a)anthracene 8100 10762 36936 299180 101 #N/A #N/ABenzo(a)pyrene 810 24401 172561 139774 47 1.41 33Benzo(b)fluoranthene 8100 58425 1154481 9351299 3159 #N/A #N/ADibenz(a,b)anthracene 810 21878 154719 125322 42 #N/A #N/APCB 10000 100000 1976000 19760000 6676 0.08 833431,3,5-Trinitrobenzene 102000 3 6.36 649 0.22 75 0.0032,4-Dinitrotoluene 8700 15 12 102 0.034 17.7 0.0022,4,6-Trinitrotoluene 1a 47000 6 1.4 65 0.022 3.94 0.006RDX 1Cyclonite 1Hexahyd 1000 212 135 135 0.046 10.4 0.004Cyclotetramethylenetetran 51000000 1 0.1 4455 1.5 151 0.01

3/19/98

FCM Lookup

Log Kow Trophic Level 2

risk.xis

3.94

4.14.24.34.44.54.64.74.84.9

55.15.25.35.45.55.65.75.85.9

66.16.26.36.46.5

7

11.11.11.11.11.21.21.21.31.41.51.61.71.92.22.42.83.33.94.65.66.88.210131519

1

3/19/98

..........

APPENDIX D

LABORATORY REPORTS

APPENDIX D

laboratory Reports

Laboratory reports have not been reprinted for this draft final document in order to conserve paper resources.

Copies will be provided upon request. The final report will contain all laboratory reports.

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Drsft Final)

March 19. 1998Page D-1

APPENDIX E

FIELD LOGS

APPENDIX E

Field Logs

Field logs have not been reprinted for this draft in order to conserve paper resources. Copies will be

provided upon request. The final report will contain all field logs.

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft Final) 1

March 19. 1998Page E-7

...

APPENDIX F

AQUATIC MICROINVERTEBRATES

APPENDIX F

Aquatic Macroinvertebrates

Laboratory sheets listing the taxa and numbers of aquatic macroinvertebrates at each sampling site are

attached. Physical habitat survey data sheets are found in Appendix E.

Iowa Army Ammunition PlantEcological Risk Assessment Addendum (Draft) I

October 23, 1997/Rev. 1Page F-l

Appendix F. Table A. Benthic Macroinvertebrates Collected from Brush Creek

Taxa PollutionBCI BO BCJ BC4 BCS BC6 BC7 BC8 BC9 BClOTolerance

Ephemeroptera Baetidae 4 18 I 1\ 3 3 41 13 2

Caenidae 7 2 I I 2 2 1 15

Heptageniidae 4 2 I

Isonychiidae I I

Odonata Aeshnidae 3 I I 4

Coenagrionidae 9 2 I

Trichoptera Helicopsychidae 3 3 2 9

Hydropsychidae 4 1\5 20 160 38 67 74 94 1\2 9 19

Hydroptitidae 4 I 4 I 2 I I

Philopotamidae 3 2

Coleoptera Dryopidae 5 I 4 7 2 3

Elmidae 4 7 3 5 6 4 4

Dytiscidae I

Lampyridae I

lGyrinidae I

Limnichidae I

Diptera CyciorrhaphoDs-I

Brachvceraeratopogonidae 6 I I

red Chironomidae 8 3 9 2 4 1\

other (& pink) 6 3 2 50 66 50 33 14 36 8 29

Simuliidae 6 2 66 3 45 106

Tabanidae 6 6

ipulidae 3 I

Empididae 6 2 3 I

Amphipoda Gammaridae 4 I 3

Isopoda Asellidae 8 158 2 1\ 14 2 10 4 38 141

Gaslropoda Gyraulus 8 I

Physa 8 4 13

Oligochaeta 7 3 13 7 4


March 19. 1998Appendix A

;!

i - IAppendix F. Table A. Benthic Macroinvertebrates Collected from Brush Creek

Taxa PollutionDCI DC2 BC3 DC4 DCS DC6 DC7 DeB DO DCtO,

Tolerance -Hemiptera I 1 2 1 . 2

Arachnid,

I

Collembola Entomobryidae 1

Turbellaria 4 1 12

Nematomorpha 1-

Pelecypoda 2 , ,Number of taxa 8 II 12 8 12 13 10 17 13 12

Tn<ol· 70.1 110 7" 178 'd, 117 1001 70' "0 233

',1(\',·

_.


March 19. 1998Appendix 8

Appendix F. Table B. Benthic Macroinvertebrates Collected fromLong Creek. Spring Creek and Skunk River Tributaries

Taxa Pollution LCTI LCT2 LCT3 LCI LC2 SRTI SRT2 SCI SC2 SC3 SC4 SCS SC6ToleranceEphemeropterara Baetidae 4 8 2 \ 4 12 2 1\ 4 4 2\ I

Caenidae 7 9 \

Heptageniidae 4 I 5Odonata Aeshnidae 3 \

Trichoptera Helicopsychidae 3 10 I 5 7 1Hydropsychidae 4 12 6 \ 13 74 28 2 14 16 35 54 82 65Hydroptilidae 4 \5 4 1 1 II I

Philopotamidae 3 3Sericostomatida 3 I \

Coleoptera Dryopidae 5 3 I 6 2 2 \ 3Elmidae 4 2\ 3 I 3 10Dytiscidae 2 I 2 I 4Lampyridae \

Diptera Ceratopogonida 6 I 13 \ I

red 8 1 2 32 62 103 \6other (& pink) 6 32 3 24 7 48 18 7 3 8 42 \98 54 70

Simuliidae 6 4 1 3 2 3 \ 2Tabanidae 6 \ 1Tipulidae 3 2 \ I 2 \

Empididae 6 3Amphipoda Gammaridae 4 5 \2 6 38 13 \ 6 12 36 16 24Isopoda Asellidae 8 71 233 100 115 2 35 81 112 6 15 \

Gastropoda Ferrissia 6 4 3Physa 8 \6 \ 54 6 2 10 40 20 \5 \ 4

Oligochaeta 3 2 \ I 5 25 ! , 1 4 I

Hemiptera \ 3 1-Arachnid 3 I 1

Iowa Army Ammunition Plant ;;.._." _Ecological Risk Assessment Addendum (Draft Final)

March 19, 1998Appendix C

... ..

Appendix F. Table B. Benthic Mllcroinvertebrates Collected fromLong Crtek. Spring Creek and Skunk River Tributaries

_.~, ~<" .11I1<s .::::tlliion LeTt Len LeT3 l.et LC2 ! SRTI SRT2 SCI SC2 SC3 SC4 SCS SC6

k~ance

Tmbellaria •Nematoillorpha > 1Annelida 3Pelecypods . I 6 81 4; 14 43

Number oftaxa U 9 8 1\ 16 12 10 It 15 III 10 II 18Tnt••. .. 171 7h 19'1 I ~J ,.. I~l 17' ... 10h 'hoi 1~1 10" 7"


March 19. 1998Appendix D

per the federal facility agreement for iowa army

Documents