Declaration for the Record of Decision

Site; Arable; Asbestos FilesBorough of AmblerMontgomery County, Pennsylvania

Statement of Basis and Purpose

This decision document represents the selected remedial action for thesecond operable unit at the Ambler Asbestos Site, in Ambler, Pennsylvania,developed in accordance with the Comprehensive Environmental Response,Compensation and Liability Act of 1980, as amended by the SuperfundAmendments and Reauthorization Act of 1986 (CEROA), 42 U.S.C. Section 9601et seq. and to the extent practicable the National Contingency Plan (NCP),40 C.F.R. Part 300. This decision is documented in the contents of theAdministrative Record for this site, itie Conroonwealth of Pennsylvania hasconcurred on the remedy. ^

Assessment of the Site

Pursuant to duly delegated authority, I hereby determine, pursuant toSection 106 of CERCIA, 42 U.S.C. Section 9606 that actual or threatenedreleases of hazardous substances from this site, as discussed in "Summaryof site Risks" on pages 14 - 18, if not addressed by implementing theresponse action selected in this Record of Decision, may present animminent and substantial endwgerment to public health, welfare or theenvironment,

Description of the Selected Remedy

This Operable Unit is the second and final of two operable unitsplanned for the site. Both operable units address the potential release ofasbestos from the site by containing the asbestos-contaminated waste piles.Operable unit 1. addresses the Locust Street and Plant Piles on the portion

AR302376

.

U tkt page, iilntd in thi* <*awe U not <u utadablt_j*. legible, <u,label, it LA due to AubAtandaitd colon ot condition o{ the oniginal page.

r\ of the site owned by Nicolet, Inc. This Operable Unit addresses the PipePlant Dump (CertainTeed Pile) on the portion of the site owned byCertainTeed Corporation.

The major components of the selected remedy are as follows:

- The pile plateau will be regraded to promote proper drainage ofstorwater.

- A soil cover with a geotextile reinforcement where necessary willbe installed on portions of the plateau and side slope areas wherethe existing soil cover is less than two feet,

- Additional borings will be collected in the pile plateau and sideslopes to determine cover thickness and define soilcharacteristics. .

"*!•

.--N, - Performance of a verification study to determine source of-; inorganics in Stuart Farm creek.

- Erosion on waste pile slopes due to storm events, soil creep,freeze/thaw effects., etc. will be repaired with a geotextileliner and additional soil cover.

- Erosion control devices will be installed to protect the toe ofthe pile from the scouring action of Stuart Farm Creek.

- Erosion/sedimentation controls will be implemented during remedialactivities to facilitate the establishment of vegetation.

- Installation/Upgrade of fencing/locking gates and posting ofwarning signs.

J.

AR302377

H tkt pagt iUmtd in thi* <*ame it not <u Htadabtt..on ttgiblt a.,label, it it due to AubAtandcud colon 01 condition o{ the. oniginat page.

Mr monitoring for asbestos will occur during remedial activities(personnel and environmental).

Post-closure inspections, monitoring, and maintenance of the pile,and preparation of a contingency plan will be accomplished,

Declaration

The selected remedy is protective of human health and the environment,attains Federal and State Requirements that are applicable or relevant andappropriate to this remedial action (or a waiver is justified) and iscost-effective as set forth in Section 121(d) of CERCIA, 42 U.S.C. Section9621 and Section 300.68 of the NCP. This remedy utilizes permanentsolutions and alternative treatment technologies to the maximum extentpracticable. However, because treatment of the principal threat of thesite was not found to be practicable, this remedy does not accomplish thestatutory preference for treatment as a principal element of the remedy.It should be noted that, since asbestos cannot be combusted and isessentially chemically inert, a permanent remedy as such cannot beeffectively implemented at this site. Therefore, this remedy becomes theonly currently feasible remedy under CERCIA for asbestos at this site.

Because this remedy will result in hazardous substances remaining onsite above health-based levels, a review will be conducted bi-annually forthe first five years after initiation of remedial action and yearlythereafter, and this complies with the requirements for review set forth inSection 121(c) of CERCIA, 42 U.S.C. Section 9621(c).

Date Edwin B. EricksonRegional Administrator

AR302378

O

U tht page, iilmd in thiA inane. U not at nt.ado.btt ..on legible, a* thi*label, it iA due. to AubAtandand colon on condition ol the, oniginal page..

Table of Contents0 *°<

Decision Summary

SECTION PAGEI, site Name, Location and Description ,..,,,,..,,,,,.,,.,,., 1

II. Site History and Enforcement Activities ......,,,,..,..,.. 1

III. Community Participation .................................. 5

IV. Site Characteristics ..................................... 5A. Air Quality/Geology/Hydrology ........................ 5B, Extent of Contamination .............................. 9C. Statement of Findings Regarding wetlands ............. 13

"'''•*»V. Summary of Risks ......................................... 14

/•~~\. J A. Exposure Assessment .................................. 16

B. Focused Risk Assessment .............................. 17

VI. Remedial Action Objective ................................ IS

VII. Description of Alternatives .............................. 19

VIII. Comparative Analysis of Alternatives ..................... 28

IX. The Selected Remedy ...................................... 31

X. Statutory Determinations ................................. 32

XI. Documentation of Significant Changes ..................... 39

APPENDIX

ij A. Responsivenesi Sunaary

B. State Letter of Concurrence]\

AR302379. . ..

•;'- H tht page, Imed in tkiA <*ai*e iA not a* , , , , .label, U iA due. to AubAtandaid colon on condition oi the. oniginat page.

I. Site Name, Description and Location

The CertainTeed Pile site (a portion of the Ambler Asbestos site) islocated in the southwestern portion of the Borough of Ambler, MontgomeryCounty, Pennsylvania (Figure 1). The site is approximately five acres insize and is adjacent to the southeast corner of the Nicolet, Inc. Plantpile. The site is further bounded on the southwest by a wastewatertransmission line and easement, on the southeast by Stuart Farm Creek, andon the east by railroad tracks (Figure 2). The CertainTeed Asbestos pileencompasses approximately 3.5 acres.

II, Site History and Enforcement Activities

The CertainTeed Pile site reportedly received primarily asbestos-containing solid pipe scrap from 1962 to 1974. During the years that theCertainTeed Pile was active,^here were two types of manufacturing wastematerial disposed at this site?**The first was a 51 solids sludge, whichconsisted of 32t calcium carbonate and 654 hydrated cement and silica, lessthan 21 asbestos and approximately It minor miscellaneous components, Thissludge, which was waste material from the process water treatment settlingponds, was transported to the scrap pile via tank truck.

The second type of waste was Asbestos-Cement (A-C) scrap whichoriginated mainly from reject pipe and pipe lathe turnings generated duringthe pipe finishing operation. This A-C waste consisted of a mixture of10-20-1 asbestos fiber interlocked within a 80-90* calcium silicate complexmatrix which was created by autoclaving the mixture under a high pressure(150 psi) saturated stean (350-370 degrees F). The resulting matrixbecomes a type of synthetic rock-like structure. The pipe scrap was hauledto the scrap pile by Globe Trash Disposal Service. From time to timeCertainTeed hired an outside company to bulldoze the pipe in order tocrush, flatten and consolidate the waste.

The CertainTeed Pile site lies within the Delaware River drainagebasin. The area is characterized by relatively flat topography withoccasional rolling hills with the greatest change in relief occurring along

(1) AR302380

H tkt page. Ulntd in thiA Inatm iA not aA ntadable..to* Itgiblt HA 4-label, *.t LA due. to AubAtandand colon on condition o< the. oniginal page..

FIGURE 1

SITE LOCATION MAP

U the. page --Ulmed in thiA inane. iA not aA ntadable. on ttaiblt HAlabel, u 4.* due to AubAtandand colon on condition oi the

5

S

\

U tht page 4ilme.d i /:fci4 ^ame it not O.A readable .0* legible, a* ...;label, it <4 due to tub4tanda*d colo< o« condition o{ the original ipage.

/TV the flood plains of the many creeks and tributaries that flow through thisarea. Elevations within a mile of the site range from 160 to 300 feetabove Mean Sea Level (NSL). The CertainTeed Pile rises approximately 45feet above the natural grade.

The site is located adjacent to the 100 year floodplain of StuartFarm Creek. Stuart Farm Creek flows along the southeastern side of theCertainTeed Pile, The portion of Stuart Farm Creek adjacent to the pilehas an associated wetlands system. The wetlands system occupies anapproximately 10 - 15 foot wide band along the Creek and joins theWissahickon Creek flood plain approximately 300 feet downstream from thepile.

Land use around the site includes industrial, residential,commercial and transportation. The CertainTeed Pile site is located withinan industrial zoned area along the southwest border of the Ambler Boroughline. Residential housing ancttft adjoining playground are locatedapproximately 300 feet east of the site. Numerous educational and

--' recreational facilities are located within 1.2 miles of the site.Agricultural land is located approximately 2,000 feet to the west of theAmbler Asbestos site. The CertainTeed manufacturing area and theSoutheastern Pennsylvania Transportation Authority (SEPTA) Commuterrailroad are located east-northeast of the site, 100 to 200 feet away. Ametal fabricating plant and a wastewater treatment facility are locatedapproximately 200 feet to the east and southeast of the site respectively.

Starting in 1968, CertainTeed undertook an intensive program todevelop the technology to recycle the waste generated during themanufacturing process. In early 1972, at the request of the PennsylvaniaDepartment of Envircnwntal Regulations (PADER), and as required for filinga solid waste disposal permit, a study was conducted to evaluate the impactof sludge leachate on surface and ground waters. The results of thestudies found that the dumping procedures had little or no noticeableimpact on surface water or groundwater.

o(2)

AR3G2383

H tht page, filmed in thiA inane. iA not aA ntadable. on Itgiblt tA thiAlabel, it iA due to AubAtandand colon on condition o] the. oniginal page..

By 1974, the recycling program progressed to a point where all of ^the waste sludge could be recycled back into the manufacturing process thuseliminating the need to truck it to the waste pile. The portion of thedump which was used for sludge dumping was then covered with dirt andvegetated.

During this same time period, the pipe manufacturing technique wasimproving and the quantity of the scrap pipe that needed to be taken to thewaste pile was continually declining. Progress also continued on therecycling of autoclaved pipe scrap into the manufacturing process, and byearly 1977, CertainTeed had developed the ability to reuse most of thishard waste. The dumping of pipe waste was discontinued when theCertainTeed Pile was closed in 1977 in accordance with the conditions of a"Consent Order" with PADER in consultation with EPA. The total quantity ofasbestos-related waste material is approximately 110,000 cubic yards whichis covered with approximately 22,000 cubic yards of soil.

"•H*

After the phase out of the, CertainTeed Pile, whenever the pipe scrap x»,generated by the manufacturing process could not be totally recycled, theexcess was taken to the Montgomery County landfill. This procedurecontinued until the manufacturing operations at the plant were discontinuedon January 8, 1982.

The Ambler Asbestos Site was proposed for placement on EPA'sSuperfund National Priorities List in October 1984 and was ranked 523 of703 when promulgated on the NPL on June 6, 1986.

On November 11, 1985, the CertainTeed Pile was inspected by U.S.EPA, PADBR, HESTON and CertainTeed Corporation. The cover on the pile wasfound to be in relatively good condition and well vegetated. Evidence ofminor erosion and scouring was observed along the south side of the pile byStuart Fara Creek. The observations indicated a low potential for pilestability problem and/or cover loss over the short term. EPA and PADERdecided that surface water and sediment samples of the creek and water

(3)

flR30238l*I{ the page iilntd in thiA inane. iA not aA ntadable...on legible, aA thiAlabel, it iA due. to AubAtandand cololi on condition oi the. oniginal page.

samples from the shallow aquifer under the floodplain area adjacent toWissahlckon Creek would be taken by the EPA FIT team to verify that nocontaminants of concern were migrating from this source.

On Nay 12, 1986 the NUS FIT III team took five (5) water samplesfrom Stuart Farm Creek adjacent to and southeast of the CertainTeed Pile,The samples were analyzed by Transmission Electron Microscopy (TEN).Chrysotile asbestos fibers were detected both upstream and downstream ofthe closed site, The average concentration of two aqueous samples bothupstream and downstream was 42 MFL (million fibers per liter),

In Hay 1987, EPA notified CertainTeed of its potential liability forthe CertainTeed Pile, and provided it with an opportunity to perform an(RI/FS) on the CertainTeed Pile. At the same time EPA was performing anRI/FS on the other two piles (the Nicolet Piles). Due to the scheduling ofthe EPA RI/FS it was mutually agreed that CertainTeed would collect thenecessary HI data and EPA wotiWHncorporate this information into its FS.In December, 1987, CertainTeed signed a Consent Order where they agreed tocollect said data.

During CertainTeed's 1988 investigation, asbestos was detected inthe onsite air, the CertainTeed Pile and in Stuart Farm Creek. Inaddition, organic and inorganic compounds were detected in the pile and insamples from the Stuart Farm Creek both upstream and downstream of thepile. The inorganic compounds including arsenic, chromium, cadmium, lead,nickel, zinc and copper were found both in the pile and in upstream anddownstream samples from the creek. Other potential sources for thesecontaminants exist adjacent to the Stuart Farm Creek upstream of theCertainTeed Pile. Consequently, the actual source or sources of theseinorganic compounds in the creek cannot be verified at present. Therefore,a verification study will be required prior to implementation of the chosenalternative in order to better define the source of these inorganiccontaminants.

(4)A p C; fi ° o r> c;HrioUriOoO

H tht page filmed in thiA inant iA not aA ntadable.,on Itgiblt a A thiA-label, it iA due to AubAtandand colon on condition oi tht oniginal page.

Ill, Community Participation

o in accordance with Section U3(k)(2) and 117 of CERCIA, onAugust 16, 1989, EPA placed a quarter page advertisement in the AmblerGazette announcing the 30 day comment period on the Proposed Plan for thesecond operable unit of the Ambler Asbestos site. Also announced was theavailability of the Proposed Plan and supplemental documentation in theAdministrative Record and the site repository) the Ambler Branch of theWissahickon Valley Public Library. In addition, the announcement providedthe opportunity for a public meeting upon request,

The public comment period began August 18, 1989 and ended September18, 1989. There were no requests for a public meeting and no comnnts tothe Proposed Plan.

IV. Site Characteristics " '**

A. Air Quality/Geology/Hydrulogy-J

1. Air Quality

The CertainTeed Pile site is located in the MetropolitanPhiladelphia, Interstate Air Quality Control Region (U.S. EPA, July, 1987).

" This region is classified as an attainment area for all criteria pollutantsexcept photochemical oxidants (precursors to ozone). This Air QualityControl Region is currently classified as secondary nonattainment forparticulate utter (1W), primary nonattainment for carbon monoxide (CO)and, prisvry nonattalnmtnt for photochemical oxidants (VOCs which areprecursors to oiont). The area, however, is currently unclassifiable orbetter then national standards for sulfur oxide (SO,). Locally, airquality is potentially impacted by industrial and private sources.

J(5)

AR3C2386

H tht page filmed in thiA iname. iA not aA ntadablt.onltgiblt.aAthiA-labtl, it iA due to tubAtandand colon on condition oi tht oniginal page.

The following potential sources of asbestos are located in Amblernear the CertainTeed site: o

o "East and West Maple street" Pile and berm around the ReservoirArea.

o CertainTeed Plant Area.o Nicolet Plant Area.o Nicolet Piles and Lagoon Area.o Other background asbestos near the site.

2. Geology

The site study area is underlain by bedrock of the StocktonFormation of Trlassic age. The Stockton Formation is described byBarksdale (1958) as consisting of light-colored, coarse-grained, arkosicsandstone and conglomerate; red to reddish arkosic units are the mostcharacteristic of the Formation, especially the lower members of theStockton Formation that undarl the site. Individual layers within theStockton Formation commonly pinch out or grade into beds of differenttexture or mineralogy, and rarely can be traced for any significantdistance. Sequences of beds, however, may persist for several miles. w

The Stockton Formation crops out in an east-northeast trending bandapproximately five miles wide in the Ambler area. Bedding strikesnortheast and dipt to the northwest at 10 to 20 degrees, Bedding planescomnonly show ripple marks, mud, cracks, raindrop impressions, crossbedding, and pinch and well structures. The thickness of the unit rangesfrom 1,000 to 5,000 feet and probably averages about 3,000 feet near thesite. The Formation is extensively faulted and is cut by at least two setsof verticil joints, one parallel to strike acd one at about a 50 degreeangle to strike.

Weathering of tht Stockton formation generally results in depositsof sandy clay loams of variable thickness that form an undulatingtopography of moderately low relief, valleys are typically eroded into the

(6)

AR302387

li tht page filmed in thiA inane. iA not aA madablt,.on Itgiblt aAlabel, it iA due to AubAtandand colon on condition oi tht oniginal page.

softer sandstone beds while uplands are more commonly underlain by thearkosic beds. The depth of bedrock in the study area has been estimated tobe less than 10 feet (Preliminary Assessment/Site Investigation, NUS,1983). However, it has been reported that quarry activities may haveoccurred under the Locust Street Pile (Johnson and Schroder, 1977)

3. Hydrology

a. Groundwater Hydrology

Groundwater flows in the Stockton Formation through both primaryintergranular openings as well as secondary joints and faults. Flowdirection is locally quite variable and hydrologic boundaries are frequent.In general, regional groundwater flow is either along the strike of theformation or down dip. To a great extent, the occurrence and movement ofgroundwater in the Stockton formation is controlled by the configuration ofthe base of the weathered zoniUsid by vertical changes in the permeabilityof the deposits (Barksdale et al., 1958). in the vicinity of the wastepiles, groundwater flow is expected to be toward Hissahickon Creek.Shallow flow is likely to be unconfined while deeper groundwater is underartesian or semiartesian conditions. The depth to groundwater has beenreported to be less than 5 feet in this site area.

Aquifer tests in the Stockton Formation (semiartesian deeper groundwater) indicate that the unit is one of the best sources of ground water insoutheastern Pennsylvania. Transmissability ranges from 1,000 to 35,000gallons per day per foot (gpd/ft) with typical values between 5,000 and9,000 gpd/ft. The storage coefficient ranges from 0.0001 to 0.000001indicating s range of conditions from semiartesian to true artesian. Hellyields range from 1 to 900 gallons per minute (gpm) with typical valuesfrom 50 to 100 gpm. Specific capacity varies from 0.35 to 44 gpm/ft with amedian value of about 6 gpe/ft (Barksdale et al., 1958; R. E. WrightAssociates, Inc., 1982).

(7)fl o o r. '•) '•;• o Qn 1 1 0 u t. o 0 0

li tht page ililmed in thiA {/tame iA not aA ne.adablt.,on Itgiblt.a* thiAlabel, it iA due to AubAtandand colon on condition oi tht oniginal page.

Hater quality in the Stockton Formation is generally good but highlyvariable depending on local hydron«ologlc and land use conditions: Typicalvalues of water quality parameters are: iron, 0.10 mg/1; manganese, 0.04mg/1; bicarbonate, 84 mg/1; nitrate, 10 mg/1; sulfate, 24 rag/1; totaldissolved solids, 150 mg/1; hardness 100 mg/1; specific conductance, 250micro-ohms/cm; and pH, 7.2 (R. E. Weight Associates, Inc., 1982). Haterfrom the Stockton Formation is a primary source of drinking water Cor anumber of private and public users including the Borough of Ambler,

Hater supply for the site area is provided by the Ambler BoroughHater Department through a series of nine supply wells. During the periodfrom July through December 1983, individual supply wells pumped between 60and 730 gallons per minute for a weekly total of between 1,500 and 2,400gallons per minute. The municipal well nearest to the site isapproximately 0.4 miles east of the CertainTeed Pile. This well is 500feet deep, and pumps roughly-}00 gpm (NUS, 1983). The nearest knownprivate (residential drinking ater) well is the Burke well.

Groundwater is not expected to be a significant migration pathwayfor asbestos at this site. This is due to two factors; 1) the site'slocation in a hydrologic discharge zone where generally base flow isslightly upward and toward the stream; and 2) the relative insignificantsubsurface downward or lateral migration of asbestos fibers in soil. Todate, there is no documentation of groundwater transport of asbestosparticles (Dalton, U.S. EPA, 1985).

b. Surface Hater Hydrology

Then are two bodies of water in the vicinity of the sitet StuartFan Creek and Nissshickon Creek. As described previously, Stuart ramCreek is a small feeder stream which flows in a south-southwest directionto the Hissahickon. Neither of these creeks are used as a source ofdrinking water.

li tht page tjilnerf in thiA inane. iA not aA ntadable...on Itgiblt aA thiAlabel, it iA due to AubAtandand colon on condition oi tht oniginal page.

The Hissahickon Creek runs along the west side of the Nicoletproperty, and is approximately 300 feet from CertainTeed's site. The creek

x-s flows southeast at a gradient of approximately 22 feet per mile andcontributes to the Schuylkill River. A public water supply is located onthe Schuylkill approximately 12 miles downstream from the site,

Surface drainage from the CertainTeed Pile is unrestricted atpresent, with the majority of runoff flowing towards either Stuart FarmCreek or the floodplain for the Hissahickon Creek.

The flood plain of Hissahickon creek is a groundwater discharge zoneand several permanent and seasonal springs have been reported in the area,No specific data exists on the water quality or the rates of discharge ofthe springs.

B. Extent of Contamination

1. Contamination'Rtfblem

The main contaminant of concern is asbestos. The source of"j contamination associated with this operable unit is the CertainTeed

Asbestos Pile. The routes of asbestos exposure are inhalation via ambientair and ingestion which may result from the ingestion of soil or surfacewater containing asbestos. Dermal contact is not an exposure route ofconcern since asbestos is not likely to be absorbed through the skin.

Sampling events on and near the CertainTeed Pile site havedemonstrated that asbestos fibers may have migrated offaite from the pileinto the surrounding ambient air and adjacent surface water. At present,the pile's plateau and slopes are covered with a layer of topsoil up totwenty feet thick. However, broken pieces of asbestos-cement pipe arenoticeable on some areas of the pile, possibly due to slope erosion, inaddition, trees and other large vegetation have taken root along the slopesof the pile. If this vegetation should be uprooted, a release of asbestosto the ambient air could result.

•J AR3023SO(9)

It tht page filmed in thiA {tame iA not aA *eadable.,.o* legible. a4 ,-label, it iA due to AubAtandand colon on condition oi tht oniginal page

In addition, organic and inorganic compounds were detected in thepile and in samples from the Stuart Farm Creek both upstream and downstreamof the pile. The'inorganic compounds including arsenic, chromium, cadmium,lead, nickel, zinc and copper were found both in the pile and in upstreamand downstream samples from the creek. Other potential sources for thesecontaminants exist adjacent to the Stuart Farm Creek upstream of theCertainTeed Pile. Consequently, the actual source or sources of theseinorganic compounds in the creek cannot be verified at present. Therefore,a verification study will be required prior to implementation of the chosenalternative in order to better define the source of these inorganiccontaminants.

2. Field Investigation and Analytical Program

The field investigation and analytical program was designed todetermine if potential public health risks and environmental impacts stillexist at the CertainTeed Pilfc'We and if remedial action is needed inaccordance with 40 C.F.R. section 300.68 of the NCP.

a. Investigation Results '

On August 10, 1987, EPA required that a focused EnvironmentalInvestigation (El) be conducted at the CertainTeed Pile. In response tothis requirement, CertainTeed engaged the firm AGES, of Valley Forge,Pennsylvania to conduct the focused El.

The scope of the AGES El included surface water, sediment and testpit sampling and analysis (see Figure 3); construction of borings andpiezometers in the waste pile; cover soil sampling and analysis; OSHAmandated personnel air sampling; and preparation of a report summarizingthe results of the field and analytical program. The inorganic sampleresults are presented in Tables 1, 2 and 3.

A sumnary of the results from the field investigation conducted byAGES is presented below:

(10)

AR3G239!

li tht page filmed in thiA inane. iA not aA ne.adablt..on Itgiblt aA thiA- 'label, it iA due to tubAtandand colon on condition oi tht oniginal page.

o

o

HI

AR302392

J)

l\ %

a

«?i a<M I* a

11 ft

r- o\ (o 10in m m > , , , \o

10 u> r- ui8 a a a B a 2

S > 8

. e o « «_ H • • o • • IQ * Q * r r i l ' r n r ^ 3Z C " » Z H H I O r t W Hsi1

2H

IPea a Cm H o » • • co i>1 , • . o O * w

l

* -B S

,!J« 8 a

AR302393

O

I i the page filmed in tni^ <*ame i4 not a4 <eada6l.e...o*. legible, -label, it iA due to 4ub4tanda«d colon ijn condition oi tht oniginal page. if

•li

o

J0

,toco

XI S ft

z!zi

si

g

nIN >o ™a r- oo m oin z IN T H co

S § 8 8 S g §

S £ O O H

a" s s g a S g Sf* ' «=; g 8 9 s ?i s s

8 8 8

m eo8 8 8 8 8 S 8 3

N m « ootA , * , ,a s « a s ? 5 B . .

q

aft

» K.. H .. _ K « 8

M

>H

u&u

,I |I Ia a *i l li i

AR3Q2391*

:'•- U tht page filmed in tfci ame i* not a4 . , , , ,label, it 4.A due to 4ub4tanda4d colon on condition oi tht oniginal page.

ft

s&s „ iSI I ft - R

ft

n t

a o o §o o ro o eno o i r« <N

o S H fli m f oo, ri , i , . .m r> H r> r> en MT • « (N m co oo

, ^ 8 § S 3 S S

i" -v ni 00 « * * (N(N o o m m r^ oN « * 5 R n r * m H H

9t *O O <N «?• *f • i * r*» •01 • ro t pH rn 0t«» H oo N m H en

m- «!SO H o> co ro oZ N M H in CO

s Q u

•J

jp

'S

•SS" n8S M &•a.2?Illm8, 'g&

i 38«! 1|& 28,9 .S51}***!§ -SjB.S .8* .

'28.i _5w

^ T)6

Hi«8<

flR3023S5

I{ tfce page filmed in tfci* inant iA not aA nta.dabttjn, ..label, it i4 due to 4ub4tanda4d colo« o« condition oi tht original page.

o

o Concentrations of copper (112 ppb), zinc (3,630 ppb), and nickelfj (76. S ppb), detected in a surface water sample taken from Stuart

Farm Creek adjacent to the CertainTeed Pile (S-3), were all aboveupstream concentrations (47 ppb, 130 ppb, and "not detectable",respectively) .

o The upstream and downstream sediment samples exhibited heavy metalconcentrations of similar magnitude.

o A test pit sample yielded a high concentration of arsenic (1,770ppm). The remaining levels of heavy metals within the test pit werewithin the observed range for soils in the eastern U.S. Nobackground soil samples were analyzed during this investigation,Two samples exhibiting elevated heavy metal concentrations wereanalyzed using the Extraction Procedure (EP) Toxicity test. Theresults were below the,, regulatory limits defining a waste ashazardous under RCRA, lifted in 40 CFR 261.24.

o Asbestos was detected using the transmission electron microscopyJ (TEN) in the two downstream surface water samples (S-4 and S-5), at

a concentration of .0421 MIL, A duplicate sample was collected atlocation S-4. Asbestos was not detected in the duplicate. Asbestoswas also not detected in the upstream samples. (The detection limitfor this analytical procedure was .0421 MFL.)

o Asbestos was detected using the polarized light microscopy (PUl)analytical procedure in both upstream and downstream sedimentsamples at concentrations ranging from 2 to 6 percent by volume.

o Asbestos was detected using TEH, in all of the test pit samples atconcentrations ranging from 0.2 to 11 percent by weight.

o Exposed areas of the pile were identified on the northern mostportion of the western side slope and along the toe of the southernside slope. Portions of the pile and side slopes have experiencedextensive tree growth.

O

H tht page filmed in thiA inane. iA not aA ntadablt .,on. Itgibtt a . . 4label, it iA due to AubAtandand colon on condition oi tht oniginal page.

•o A portion of the southeast slope of the CertainTeed Pile is locatedwithin the floodplain of Stuart Farm Cceek. O

o Cover soil on both the piles slopes and plateau consist primarily ofa silty or clayey sand.

o No perched or shallow groundwater was detected in any of the threepiezometers installed in the pile.

o The cover soil on the plateau portion of the pile ranges inthickness from 1 to 20 feet. The angle of the side slopes averagesm (2.5 H: 1.3V).

b. Conclusions from the Investigation

The analysis for asbestos fibers in ambient air during the test pitand test boring investigatiohMftdicate that any grossdisturbance of the in-place materials will likely cause a significantdegradation of the ambient air quality. In addition, these conclusions are _presented: W

o The potential of onsite sources of heavy metals and the consequentrisk to the environment should be further investigated.

o Surface water samples suggest that the CertainTeed Pile is apotential source of asbestos.

o The location of the pile within the floodplain of Stuart Farm Creekposes a potential risk of increased releases of asbestos into areasurface waters if flood conditions occur.

o Asbestos detected in both upstream and downstream sediment samplesindicate both off site and onsite sources.

o(12)

AR3023S7

I i tht past filmed in thiA inane. iA not aA ntadablt., on ItgibltaA thiA-label, it iA due to AubAtandand colon on condition oi tht oniginal page.

o Potential asbestos inhalation exposures also exist if a person orpersons are playing on or near exposed areas and asbestos containing

O material is disturbed.

o The potential of inhalation exposure of asbestos does exist ifexposed areas of the pile are disturbed resulting in entrainment ofasbestos.

o Extensive tree growth along the south slope has hindered theestablishment of low lying vegetation, which is necessary incontrolling erosion along the slopes.

o Historical photos indicate that surface water ponding is occurringon the plateau area of the pile. Excessive infiltration ofrainwater into the pile must be controlled via stormwater drainageand collection methods.

C. Statement of Findfrtsfr Regarding Wetlands

•••- Based on a Wetland Delineation, EPA has determined that wetlands- occur adjacent to this site along Stuart Farm Creek and within the

Wissahickon Creek flood plain.

The Stuart Farm Creek Wetlands occupy an approximately 10-15 footwide band along Stuart Farm Creek at the southern foot of the CertainTeedPile. Dominant vegetation is forested and includes sycamore, box elder andwillow, Soils are the Hydric Bowmansville silt loom and the hydrology isprovided by both surface runoff and a high groundwater table. This wetlandsystem joins the Hissahickon Creek flood plain, a large wooded flood plainwith inclusions of jurisdictional wetlands along the stream courses.

During site investigations, levelc of inorganic contaminants weredetected in Stuart Fan Creek above Federal Ambient Hater Quality Criteria(Quality Criteria for Hater 1986; SI Fed. Rea 43665; U.S. EPA, 1986).These contaminants may pose a potential threat to the environment. Otherpotential sources of these contaminants exist adjacent to the Stuart Farm

:J

(13)AR3023S8

li tht pagt filmed in thiA inane. iA not aA ntadable. ..on legible aA -label, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

Creek upstream of the site, Consequently, a verification study will beperformed prior to implementation of the selected remedy to determine thesource of stream contamination, Depending on the results of this study,further remedial activity associated with the Stuart Farm Creek may berequired.

Regardless of the results of the verification study, the selectedremedy to contain the asbestos waste: pile will also serve to contain anyinorganic contaminants within the pile, Since the pile is located withinthe flood plain of Stuart Farm Creek, erosion control devices will beinstalled upland of the existing wetland to protect the toe of the pile.This action will serve to minimize potential harm and adverse effects tothe wetlands in accordance with Executive order 11990 (Protection ofWetlands) found at 40 C.F.R. part 6 Appendix A.

V. Summary of Site Risks

The Endangemnt Assessemt (EA) addresses the potential humanhealth and environmental impacts associated with the CertainTeed Pile siteunder the no-action alternative, that is, in the absence of remedialcorrective action.

The results of sampling performed during the investigations, insoil, surface water, sediment, and air were reviewed to identify chemicalsto be evaluated in this EA. Chemicals were selected for detailedevaluation if they were present in environmental media at concentrationsabove background concentrations and/or could be related to past disposalpractices at the site.

The contaminant of concern at the CertainTeed Pile is asbestos; inparticular, the potential for asbestos to be released to the ambient air.Asbestos is a recognised human carcinogen, causing lung cancer andmesothelicBS, a form of neoplau of the lining of the thoracic andabdominal cavities, in workers exposed by inhalation. The associationbetween asbestos exposure by inhalation and lung cancer was first reportedin 1935.

O(14)

1R3023S9

H tht pagt filmed in tni.4 inant i4 not aA readable ..o*. legible, a*label, it iA due to AubAtandand coi',on on condition oi tht oniginal pagt.

There is also evidence that oral exposure of humans to asbestos maybe associated with an increased incidence of cancer of the gastrointestinal

^ tract. Exposures have been through drinking contaminated water, either'• -•' from contact with asbestos deposits or transmission through

asbestos-containing cement water mains. The evidence is consideredequivocal at this time,

Long-term exposure to asbestos fibers and contaminated dust alsocauses asbestosis, a progressive and irreversible lung diseasecharacterized by diffuse interstitial fibrosis, Symptoms include shortnessof breath, cough rales, clubbing of the fingers, and weight loss,Pulmonary changes occur more rapidly in more severely exposed individuals,

Groundwater is not expected to be a significant migration pathwayfor asbestos at this site. This is due to two factors; 1) the site'slocation in a hydrologic discharge zone where generally base flow isslightly upward and toward the stream; and 2) the relative insignificantsubsurface downward or latera\njgration of asbestos fibers in soil, Todate, there is no documentation of groundwater transport of asbestosparticles (Dalton, U.S. EPA, 1985).

The surface water pathway for asbestos exposure is also of littleconcern since neither the Stuart Farm or Hissahickon Creeks are sources ofdrinking water, in addition, existing studies and evidence regarding thetoxicity potential of asbestos to aquatic life is limited.

Other reported contamination in the pile is of little or noconsequence because of low reported levels or because of their presence indeep areas of the pile. In addition, the inorganic contaminants detectedin the pile are not likely to be mobile based on the reported results ofthe EP toxicity test and the expected high pH of the waste materiel. Someof the inorganic concentrations detected in surface water and sedimtnts ofthe Stuart Farm Creek ace above Ambient Hater Quality Criteria andtherefore are of potential concern to aquatic life. However, pending the

(15)

flR302iiOO

H tht pagt filmed in thiA inant iA not aAntadablt.onltgibltaAthiA*label, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

results of the source verification study, these contaminants cannot be /•>definitely attributed to the site, and therefore were not evaluated furtherfor the purpose of this EA.

A. Exposure Assessment

1. Routes of Exposure

There are two general routes through which individuals may beexposed to contaminants at the CertainTeed Pile: inhalation and ingestion.Dermal contact and subsequent absorption of asbestos is not an exposureroute of concern since asbestos is not likely to be absorbed through theskin.

For the inhalation pathway, individuals may breathe asbestos fiberswhich are present in ambient air and asbestos fibers which are present dueto specific activities which'set! up fibers. Although fenced, the site isaccessible to trespassers (e.g., children riding bikes, playing on pilesetc.). Activity on site may entrain asbestos fibers into the ambient air, O

Trees which have grown on the pile's slopes and plateau may overturnpotentially exposing asbestos contaminated soil to the environment. Theproliferation of trees onsite has also served to reduce lowlying vegetation(grass, weeds, etc,), Without this vegetation, potential for soil erosionis increased and contaminated soil may become exposed, in addition,several areas of the pile have pieces of piping and other asbestos-relatedmaterial exposed to the ambient air. Entrainment of asbestos fibers mayoccur via wind or physical disturbance of these exposed areas.

Ingestion exposure may occur as a result of ingestion of soilcontaining asbestos. Indirect ingestion of asbestos which has been inhaledis another form of ingestion exposure, Individuals may directly contactand inadvertently ingest contaminants present in soil on the pile which mayadhere to hands, toys, tools, etc.

(16)

U tht pagt {ilntd in thiA inane. iA not aA ntadable. .on Itgiblt aA thiA-label, it iA due to AubAtandand colon on condition oi the. oniginal pagt.

2, Potential ReceptorsO

There are a number of potential receptors within the vicinity of thesite, The nearest residence is approximately 300 feet east of theCertainTeed Pile. In addition, an estimated 6,000 people live within ahalf-mile of the site.

Finally, the metal fabricating and wastewater treatment facilitiesare located to the east and southeast of the site, while the CentralBusiness District of Ambler is located approximately one-half mile north ofthe site.

B, Focused Risk Assessment

The primary hazard associated with the CertainTeed Pile is thepotential for contact with asbestos contaminated media.

Risks from the pathways of inhalation and ingestion werecharacterized by first comparing concentrations of chemicals in the sampled

•-' environmental media to Applicable or Relevant and Appropriate Requirements(ARARs) identified for the site. For asbestos, based on the comparison tothe chemical-specific ARARs listed in Section IX, it was concluded thatunder present conditions the criteria related to air quality is notcurrently being exceeded. In the future, however, increased erosion andweathering of the piles could increase the potential exceeding theregulatory limits. In addition, these limits would likely be exceeded ifthe site were disturbed by vehicular activities. Such activities wouldmost likely occur as part of a remedial action involving excavation andremoval of the soil from the site. These activities could elevateconcentrations of asbestos within local surface waters.

It was concluded that potential releases of asbestos to ambient airfrom the CertainTeed site may occur due to the existence of exposed areascontaining asbestos. It was further concluded that potential human healthrisks to nearby residents may be associated with releases of asbestos fromsuch exposed areas at the site into ambient air,

O'(17)

AR3G2W2

H tht pagt iitntd in thiA inant iA not aA ntadablt_.on Itgiblt aA thiA • •label, it iA due. to AubAtandand colon on condition oi tht oniginal pagt.

Potential asbestos inhalation exposures during specific types of ^activities that can stir up asbestos fibers, such as children playing insoil on the pile, were also qualitatively evaluated. Under present siteuse conditions, activities that could stir up asbestos fibers includeplaying and hiking on the pile by children or other trespassers. It wasconcluded that these and other activities could continue to occur in theabsence of site remediation (i.e., under the no-action alternative). Amongsubpopulations who may repeatedly engage in these types of activities,cumulative asbestos exposures of concern to human health could potentiallyresult. Given the above, the site thus presents an imminent andsubstantial endangerment to public health as set forth in Section 106 ofCERCLA, 42 U.S.C. Section 9606.

VI. Remedial Action objectives

Remedial action objectives consist of medium-specific or operableunit-specific goals for protecting human health and the environment.Remedial action objectives aimed at protecting human health and theenvironment should specify: f\

- The contaminant(s) of concern- Exposure route(s) and receptor(s)- An acceptable contaminant level or range of levels for each

exposures route (i.e., a preliminary remediation goal)

The overall objective of the remedial action program for theCertainTeed Pile is to remediate the sources and/or pathways for migrationof asbestos, which were identified through the AGES El report, and the Elreview. This action is required so that potential present and futureexposures will be within acceptable limits and, that site related ARARs aremet. In addition, the development of remedial action objectives for theCertainTeed Pile should be consistent with those objectives outlined foroperable unit number one.

The specific remedial action objectives that have been developed forthis site are as follows;

O(IB) AR3024G3

H tht pagt iilntd in thiA inane. iA not aA readable ,p* legible, a*, n.label, 4.t 4.4 due to AubAtandand colon on condition oi tht oniginal pagt.

o Effectively restrict access to unauthorized persons. TheseO persons would consist primarily of trespassers, mostly children

who have frequently accessed the site, based on historicalreports. This objective would no longer be relevant, however,should a complete removal action be implemented.

o Effectively remove, stabilize, or contain the asbestoscontaminated media onsite so that potential directcontact/incidental ingestion exposures to onsite receptors areminimized, and potential releases of asbestos to ambient air andpotential releases of asbestos to adjacent surface waters arenot prevalent in concentrations which would create unacceptablerisks to on and offsite receptors,

VII. Description of Alternatives'"•*•

This section sunmorizes the candidate remedial action alternatives.-, These alternatives have been developed based on the following•J considerations:

o Those technologies outlined, defined as applicable to theCertainTeed Pile site.

o Technologies that are complementary or interrelated werecombined into alternatives. For example, one remedialalternative - excavation/offsite disposal combines thetechnologies of complete removal, surface watermanagement/erosion controls and off site disposal,

o The alternatives were developed to address the remedial actionobjectives established for the site. However, not all of thealternatives developed and evaluated will equally satisfy theobjectives or be as effective in addressing port or all of thesite Issues and contaminant pathways.

O(19> AR3G2lfOlf

li tht pagt tjilned in thiA inane. iA not aA ntadabli..onltgiblt,aAthiA-label, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

The alternative development process should cover a range of ~remediation levels, These categories include: •••.-•

1) No action: A no action alternative may include minimalactions such as installation of fences/gates and monitoringactivities,

2) Treatment alternatives ranging from one that would eliminateor minimize, to the extent feasible, the need for long-termmanagement (including monitoring) at a site, to one that woulduse treatment as a primary component of an alternative toaddress the principal threats at the site,

3) Alternatives which involve containment of waste with little orno treatment, but provides protection of human health and theenvironment by preventing potential exposure and/or byreducing mobility

With respect to the CertainTeed Pile, the remedial actiontechnologies that remained after screening were generally under the sourcecontrol classification, since onsite controls are the most appropriate tothis site.

A. Alternative It No Action with Security Improvementsand Monitoring

The purpose of evaluating the no action alternative is to provide abasis for comparison of existing site conditions with the other proposedremedial action alternatives. This alternative consists of performing nophysical remediation work to the pile. Security improvements consisting ofnew fencing, access/egress gates (with locks), and appropriate warning andinformational signs are included in this alternative. These improvementswould be designed to meet the current EPA, NESHAPS, and PADER regulationsregarding closed solid waste (asbestos-containing) landfills.

U tht page, filmed in thiA inane. iA not aA ntadable..jn, legible, a*label, it iA due to AubAtandand colon on condition oi tht oniginal pagt..

In addition, visual inspections and environmental ambient air[~^ monitoring would be performed during the following five years after

implementation in order to evaluate whether this action alone adequatelyprotects human health and the environment,

No other improvements or remedial measures would be undertaken underthis alternative.

Capital costs associated with this alternative include fencing tocomplete site enclosure, installation of gates and locks, and warning signson the fences. The total capital cost for Alternative 1 is estimated at$23,000.

Operating and Maintenance (O&M) costs are estimated at $21,000/vear.These costs are incurred during long-term monitoring for asbestos andmaintenance of the facility..

"''"*»Assuming an annual interest rate of 101, the present worth costs for

this alternative over a 30-year period is approximately $222,000.J

B. Alternative 2; Excavation/Removal - Offsite Disposal

This alternative consists of complete excavation and removal of theCertainTeed Pile waste materials to an offsite permitted/approved landfill.

The major components of this alternative include:

o Complete excavation of the waste materials, Level C activity forapproximately an estimated 50 percent of the time, specialprecautions adjacent to Stuart Farm Creek to address surfacewater runoff.

o Diversion of runon and construction of runoff containment/treatment facilities during excavation.

o Continuous air and surface water monitoring.

O(21)

AR3G2W8

H tht pagt filmed in thiA inane. iA not aA ntadablt _o« legible., a - . .label, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

o Transport equipment decontamination prior to site egress,

o Soil testing for verification of cleanup criteria.

o Hauling of clean soil fill to site and filling/regrading thesite for positive drainage,

o Revegetation and establishment of stormwater managementcontrols,

It is estimated that the pile contains approximately 110,000 cubicyards of asbestos related waste materials, and is covered by approximately22,000 cubic yards of vegetated soils.

A detailed remedial design with soil stability analyses would needto be prepared in order to perform this alternative safely due to thepotentially unstable physical ttnditiona of the interior of the pile. Inaddition, prior to and during construction, extensive health and safetyprotocols would need to be developed and implemented to minimize migrationof asbestos-contaminated wastes into the air and surface water followingexcavation into the pile. Also, it would have to be determined where thesewastes would and/or could be taken for relandfilling due to the quantityinvolved.

The capital cost for Alternative 2 is estimated st $27,980,000.Operating and maintenance (Otfl) costs are estimated at $38,300 per yearduring remedial activities (approximately 2 years) and $10,400 per yearfollowing remediation. Post-remediation costs involve monitoringactivities to verify effective cleanup (e.g., water and soil analysis, sitemaintenance).

Assuming an annual interest rate of lot and a post-remediationtimeframe of 30 years, the present worth cost of this alternative would beapproxiaately $28,145,000.

(22)

AR302M7

H^tht page, filmed in thiA inane. iA not a4 *eadable,.p* legible, a-4label, it iA due to AubAtandatd colon on condition oi tht oniginal pagt,

C, Alternative 3; Onsite vitrification via Processing Planto ——————————This alternative would involve further pilot-scale development and

analysis, and potential future construction of a full-scale vitrificationplant onsite.

Vitrification is a process wherein asbestos-contaminated materialscan be transformed by melting (at extremely high temperatures (1,300°F))into a nontoxic glass-like material. This process differs from thetechnology referred to typically as "in situ vitrification", which meltsthe contaminated material in-place using high charges of electricitytransfers to the material through probes driven into the contaminatedmaterial. Consequently, this process requires excavation of theasbestos-contaminated material, transferring the material to the treatmentfacility, and feeding the material into the furnace structure.

In simplified form, thVIRajor components and sequence ofconstruction for this alternative are as follows:

-J o Research, test, analyze, and further develop the potentialvitrification technology on a bench-scale, to a greater degreewith site-specific materials leading toward possible approval ofcertain pilot- and full-scale systems to "treat" onsite thewaste materials at this site (treatability studies).

o construct a full-scale onsite facility. Many significantfeasibility variables such as location and space requirements;electric and other utility services; financial and liabilityagreements; environmental emissions and discharge limitations;health and safety protocols; etc., would need to be worked outprior to start of construction. Electric power consumptionrequirement! for the vitrification plant, based on reported data(supplied by vendors), would be very large (estimated at 1,000kw per 1 ton of asbestos waste processed). A new electric

(23)

H tht page ijilned in thiA inane. iA not aA readable ,on legible a4label, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

substation would likely need to be constructed on or near thesite, or substantial revisions to existing facilities and major Oservice lines run to the site.

Excavate, haul, and stockpile waste materials from the pile in asequenced manner (over a number of years) in order to providethe feed material to the plant, Site preparation (runondiversion, runoff control, haul roads, etc.) similar to thosepreviously described under Alternative 2 - Excavation andRemoval, would need to be employed first, Substantial soilexcavation and health and safety concerns ( releases ofcontaminants to ambient air or surface water) would need to beaddressed first, as' previously discussed.

A "set-aside area" would have to be constructed to deal withlarge and/or foreign materials that could not be fed into theplant. These mat«&4t}» would likely require landfilling eitheron or off site.

Extensive environmental and personnel monitoring for workers and vxoffsite receptors would be required in order to quantifypotential releases and the impacts on the local ambient air.Even with required wetting and other dust/fiber suppressioncontrols, unacceptable releases may occur as a result ofexcavation and process activities may require the constructionof an enclosed work area. Even with this type of system,exhaust and emissions are imminent.

The process would most likely require substantial modificationsand/or additions as the project continued in order to deal withnew data and the waste materials types/consistmcies encounteredduring excavation.

Assuming that the estimated 132,000 cubic yards could beprocessed and/or segregated (and portions landfilled), it is notcurrently known what could/would be done with the final product.

(24)

AR3G2l»09

H tht page filmed in thiA inane. iA not aA ntadablt.onltgibltaAthiA-label, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

There may be certain potential useful purposes for the finalI.,..) product materials (i.e., roadbase materials, structural fill,

landfill intermediate cover, etc,), however, no current reusesof these materials on a large-scale have been documented) not tomention post-reuse monitoring/evaluation of final productproperties. With the current information available, it appearsvery likely that the great majority of these end-productmaterials would have to be landfilled, either back onsite in theform of a "new pile" or transported offsite to an approved .location for filling.

o At the completion of processing operations the plant would needto be dismantled and removed unless a cgntinued use for it couldbe found.

o The site would be •backfilled and regraded for positive drainage,and revegetated. iFraaterials are redeposited onsite, thematerial would be covered with a soil cover of a two-foot

--N thickness. The cover would be vegetated and graded for positive-^ drainage. It is not known at this time what volume reductions

of waste materials could be expected using the vitrificationprocess. Space constraints and slope requirements may limitonsite redisposal.

The preliminary capital cost of Alternative 3: OnsiteVitrification, is estimated at $17,257,000. Operation and maintenance(OM) costs are estimated as follows: $5,948,000 per year during remedialactivity, and $21,000 per year the 30 years following remediation, It isassumed that, using the vitrification treatment process, it will takeapproximately 7 years to complete remediation of the site. Son costsestimated for this alternative are speculative due to the technicaluncertainties that are associated with some of the components of thealternative. The total present worth cost of this alternative, assuming alOt interest rate, is $46,412,000.

H tht. page filmed in tfci.4 inane. iA not aA ntadablt..on legible a4.t«-i W.label, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

D, Alternative 4: Onsite Closure

Alternative 4 involves placement of a cover system on the CertainTeed Pile.The major components of this alternative involve the following:

o Removal of large vegetation, installation of stormwater/sedimentcontrol devices, and regrading plateau, where necessary, toassure proper drainage and cover thickness (a minimum of twofeet of clean, compacted fill),

o Repair of any erosion or exposed areas on waste pile side slopeswith a geotextile liner and low erosion/low permeability soilcover. Soil cover on slopes should also achieve a minimum twofoot thickness of clean, compacted fill.

o installation of erosion control devices for protection of thesoutheast slope from the potential scouring action of StuartFarm Creek. ""''"«•»

Revegetating site, where required, and installing erosion/sedimentation controlsvegetation establishes.

Osedimentation controls during remedial activities until ^

o Performance of a verification study to determine source ofinorganics in Stuart Farm Creek.

o Air and surface water monitoring for asbestos during remedialactivities (personnel and environmental).

o post-closure inspections, maintenance of the pile, andpreparation of a contingency plan.

o Restricting future land use to surficial activities byauthorized personnel.

Initial remedial action performed during the 1970 's involved theplacing of clean fill across the plateau and slopes of the pile. Boringsof the plateau and slopes have indicated an existing cover thicknessranging from two to twenty feet. Since this time, substantial vegetation

(26)

Aft3G2l»l!

Ji tht pagt filmed in thiA inane. iA not aA ntadablt.jn Itgiblt.a*.label, it iA due to AubAtandand colon on condition oi the. oniginal pagt.

growth (e.g., trees, bushes, grasses, etc.) has been established across theI...) entire site. Therefore, initial preparation of the site would involve

removing trees and large shrubs to pile level and regrading the plateau andslopes, where necessary, to assure proper drainage and a consistent coverof compacted soil, Geotextile material would be placed over exposed areasof the plateau and slope, followed by a layer of low-permeability topsoiland vegetated cover,

In addition, erosion control devices will be installed on the bottompart of the slope adjacent to Stuart Farm Creek to control againstpotential erosion or scouring of the pile.

Security at the site would be increased with improvements to theexisting fencing onsite and installation of additional fencing to assurethe site is completely fenced in. Locking gates would also be provided foraccess to authorized persons in the future, warning signs would be postedon the fence, related to asbestos hazards onsite.

— Inspections of the site would occur blannually for the first five--' years after remediation. A written report that details the effectiveness

of remediation would be submitted at the end of every five years (asrequired by Section 121(c) of CERCLA, 42 U.S.C. Section 9621), Annualinspections of the site will be required after the first five years toensure that human health and the environment are being adequatelyprotected. If the potential for asbestos release is noted duringinspection, air monitoring will be performed to elevate ambient asbestoslevels in air. Long-term cap maintenance such as local erosion repair,grading, seeding, etc., is required to promote cap integrity over thelong-ten.

During onsite activities, erosion and sedimentation controls such aschannels, silt fences, and jute-netting would be used as needed. Finally,a contingency plan would be developed to ensure that appropriate remedialaction will be taken if local failure of the new cap were to occur.

(27)A R 3 0 2 i » i 2

H tht pagt filmed in thiA inane. iA not aA ntadablt .on Itgiblt OA thiAlabel, it iA due to AubAtandand colo* on condition oi tht oniginal pagt.

The capital cost of Alternative 4 is estimated at $579,000,Operating and maintenance (OSM) costs, including post-treatment monitoringand maintenance, are estimated to be $21,700 per year during the first fiveyears and $10,200 .per year following that. Assuming a 10* interest rateand post-remediation monitoring time of 30 years, the present worth cost ofthe alternative is estimated to be $753,000. Since the asbestos is leftessentially in place in a secure environment, costs have been allocated forair and surface water monitoring activities for a period of five yearsafter initial remedial actions. Long-term visual inspections andmaintenance would serve to ensure cap integrity and to detect any asbestosmigration from the contained areas.

VIII. Comparative Analysis of Alternatives

This section summarizes the comparative analysis of alternativesperformed in the FFS. As outlined in the EPA RI/FS Guidance Manual -Interim Final (October, 1988) nine evaluation criteria have been developedto address CERCIA requiremenfsand technical and policy considerationswhich have proven to be important for selecting a remedial alternative (seealso the NCP at 40 CFR Section 300.68 (h)). The nine criteria aresummarized below:

o Compliance with ARARso 0/erall protection of human health and the environmento Short-ten effectivenesso Long-ten effectiveness and permanenceo Reduction of toxicity, mobility or volumeo implesmtobilityo Costo State acceptanceo Cossunity acceptance

Each alternative is evaluated below with respect to these ninecriteria.

(28)

AR3G21»I3.. . .

U tht pagt iilntd in thiA inant iA not aA ntadablt .on legible a4label, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

No Action Alternativeo ———Although this alternative would be easily implemented at minimal

capital and OSM costs, it has serious shortcomings, A No Actionalternative would not comply with the CERCLA Section 121 objective toreduce volume, mobility, or toxicity of the waste, In addition, thisalternative does not meet the remedial action objectives for the site whichrequire the alternative to minimize the potential for direct contact orincidental ingestion of asbestos from the site. Therefore, the criterionaddressing the overall protection of human health and the environment wouldnot be met. In addition, employing a no-action alternative will provideneither short or long-term effectiveness since neither the source or thepathways of risk would be reduced or eliminated, Finally, this Alternativewill not meet any ARARs in the long term. As a result, it is anticipatedthat both state and community acceptance of this alternative would beunfavorable. -.

'••«**, Excavation/Removal with Offsite Disposal

-J The alternative of excavating and removing the waste to an offsitedisposal source would provide excellent results with respect to thecriterion of long-term effectiveness. In addition, over the long-term, thecriteria of reduction of toxicity, mobility, or volume and protection ofhuman health/environment would also be satisfied since the source of theasbestos would be permanently removed. However, these two criteria wouldnot be m»t with respect to short-ten effectiveness, since the potentialfor release of asbestos to the ambient air and surface water would be quitehigh during the excavation and removal period (estimated to last 10months), As a result, on a short-term basis, compliance with all chemicaland location-specific ARARs would not be satisfied (except for the PADERrequirement for a flood plain and stream encroachment permit), Finally,the implementation and cost of this alternative would be excessive (8hrs/day - 5 days/week for 18 months at a total project cost of nearly$23,000,000).

(29)

li tht pagt filmed in thiA inant iA not aA ntadablt,on legible., a,label, it iA due to iub^tandaiid colon on condition oi tht oniginal pagt.

onsite Vitrification ^

The results' of the evaluation of this alternative are similar tothose presented for the excavation/removal alternatives. The reduction oftoxicity/mobility or volume and protection of human/environmental healthwould be satisfied on a long-term basis. However, these two criteria on ashort-term basis would not be met. The same concerns noted above are alsopresent with respect to short-term compliance of the ARARs criteria.

Finally, the implementation and total cost of this alternative arevery unfavorable with the project lasting approximately 7 years (includingtreatability, and pilot studies, and site closeout) and costingapproximately $46,000,000;

Onsite Closure

Onsite closure via cappM) with a low permeability cover andvegetation employs a proven technology which can be readily implemented.Although it would not reduce the volume of material onsite, capping the /•*•>site would significantly reduce the potential for asbestos and inorganicmaterial to be released to the ambient air and surface water by containingthe pile within a semi-permeable cover, The short-term effectiveness ofthis alternative would be very favorable since remedial activity would beperformed with limited disturbance to the waste material. Long-termeffectiveness would also be net via a maintenance and monitoring program.All Federal chemical specific ARARS are expected to be met evrn on theshort-ten since no Intrusive work would occur during capping construction.State ARARs involving landfill cover requirements would alsc be addressed.Finally, the time-frame of implementation and project costs are •. iryfavorable- (approximately 11-13 months and $750,000 respectively).

o(30)

H tht pagt ilntd in thiA inant iA not aA ntadable. .on legible aA.t! A -"••-••label, it iA due to AubAtandand colon on condition oi tht oniginal p<ge.

IX. The Selected Remedy

.i*" Section 121 of CERCIA establishes cleanup standards for the siteremediation and articulates a preference for remedial actions in whichtreatment permanently and significantly reduces the volume, toxicity, ormobility of site contaminants. The provision notes that offsite transportand disposal of hazardous substances without such treatment is leastfavored where practicable treatment technologies are available. Thestatute mandates selection of a remedial action "that is protective ofhuman health and the environment, that is cost effective, and that utilizespermanent solutions and alternative treatment technologies or resourcerecovery techniques to the maximum extent practicable."

EPA has reviewed and considered these statutory provisions and theregulations contained in the National Contingency Plan, 40 CFR Section 300,in light of the conditions present at the CertainTeed Site and concludesthat Alternative 4 - Onsite Closure is the most consistent with theserequirements. This remediabio%*lternative offers the best combination ofeffectiveness, implementability, and cost efficiency and involves the useof what can be considered the most feasible remedy under CERCIA for

J) asbestos. This alternative meets all Federal ARARS and all but oneState-related ARAR (slope requirement) for which a waiver is appropriateunder Section 121(d)(4) of CERCIA, 42 U.S.C. Section 9621(d)(4). Inaddition, the proposed cover design is consistent with other EPA and stateagency designs that have been proposed and/or approved.

The majority of the site is presently covered with clean fill up totwenty feet in sons areas, in addition, substantial vegetation is presentacross the entire site. Therefore, for those areas of the pile whichexhibit acceptable cover depth, vegetation and drainage patterns no furtherwork will be- required to have them conform to the selected remedial action.

Because this remedy will result in hazardous substances remainingonsite, five year reviews, as specified by CERCIA Section 121(c), 42 U.S.C.Section 9621(c), would be required for the remedy, despite the fullcontainment of contamination. As discussed earlier, inspections will be

'J(31)

AR3024I6

li tht pagt iilntd in thiA inant iA not aA ntadablt ,on legible aA thi4label, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

conducted bi-annually for the first five years after initiation of remedial **.action and yearly thereafter,

X. statutory Determinations

EPA's primary responsibility at Superfund site is to undertakeremedial actions that achieve adequate protection of human health and theenvironment. In addition, section 121 of CERCIA establishes several otherstatutory requirements and preferences. These include compliance withapplicable or relevant and appropriate environmental standards establishedunder Federal and State environmental laws unless a statutory waiver isjtr -\fied. The selected remedy also must be cost-effective and utilizepe .ment solutions and alternative treatment technologies or resourcerecovery technologies to the maximum extent practicable. Finally, thestatute includes a preference for remedies that employ treatment thatpermanently and significantly reduce the volume, toxicity, or mobility of,hazardous wastes as their pr'frtetpal element. The following sectionsdiscuss how the selected remedy meets these statutory requirements.

OA. Protection of Human Health and the Environment

The selected remedy will contain the asbestos contamination at thesite, which will ensure adequate protection of human health and theenvironment. This action can be expected to result in significantlong-ten reduction of potential public health risks and environmentalimpacts resulting from the direct contact and migration of asbestos fibersvia sediment, surface water, and air transport mechanisms, whileminimizing, short-tern risks to onsite workers and the environment that arelikely with other alternatives.

B. Cost-Kffectiveness

The selected remedy is the most cost-effective alternative that canprovide adequate short and long-ten protection of human health and theenvironment.

(32)AR302M7

li tht pagt filmed in thiA inamt iA not aA readable ..on legible aA tnii~label, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

C. Compliance with Applicable or Relevant and AppropriateRequirements

OThe selected remedy of onsite closure will effectively attain all

applicable or relevant and appropriate requirements (ARARs) except theaction-specific State ARAR noted below.

A summary of the existing asbestos regulatory limits or goals ispresented in C.I. below. Most of the regulatory effort to date has beenfocused on occupational exposures in industrial and educational settings,The development of guidelines for the general population has moved lessrapidly due to the complexity of sampling, analyzing and interpretingasbestos concentrations in ambient air. The existing regulations andoccupational health studies can however be used as a guideline inevaluating the quality of ambient air and water at the Ambler site,

The RCRA regulation for cap design is not an applicable requirementfor this site, because asbes'tcffHs not a hazardous waste. EPA has furtherdetermined that RCRA cap design requirements are not relevant or

- appropriate requirements for this site, for reasons set forth below.J

A multi-layered cap generally conforms to the RCRA technologyguidelines found under 40 CFR Section 264, which recommend a three-layeredsystem consisting of an upper vegetative layer over a low permeabilitylayer. The cap functions by diverting infiltrating liquids from thevegetative layer through the drainage layer and away from the underlyingwaste materials, The primary function of a RCRA cap is to controlinfiltration and leachate from the waste material that may contaminateunderlying groundwater. A multilayered cap is typically used for hazardouswaste site closures, which this site is not (based on the data collected).

Accordingly, the design of the cap need not be in accordance withRCRA regulations to be protective. The purpose of a multi-layered cap onan asbestos site is to prevent re-emergence of the waste on the surface ofthe site through the processes of wind and water erosion, freeze/thaw

•J(33)

li tkt pagt filmed in thiA inane. iA not aA ntadablt .on Itgiblt aA thiAlabel, it iA due to AubAtandand colon on condition oi tht oniginal page1.

cycles, site use, etc. In addition, it is desirable to maintain some x-\moisture content in the fibrous material to control airborne releases ofasbestos in the event of localized re-exposure. Therefore, it isprotective to use innovative cap designs at this site consisting of semi-permeable materials.

0

(34)

• !< tne page filmed in tni<t inamt iA not aA ntadabU^on. ....'label, it iA due to Aub4tandand colon on condition oi tht oniginal pagt.

1. Chemical/Contaminant-Specific ARARso —— ——REGULATION LIMIT/STANDARD

40 CFR 61.153 (Clean Air Act) Specifies standards forinactive asbestos wastedisposal sites,

40 CFR 763 (Toxic Substances Control Act)

Subpart G 2 fibers per cubic centimeter(f/cc) by phase contrastmicroscopy (PCM) (8-hr timeweighted average) for asbestos

-. abatement worker exposure."*!»

Subpart E 0.02 f/cc by TEH performancestandard for the remediation inschools.

29 CFR 1910.120 or 54 FR 9294(Occupational Health and Safety Act) Health and safety standards for

employees engaged in hazardouswaste operations.

29 CFR 1910and

29 era 192» (Occupational Health andSafety Act) 0.2 f/cc by PCM (8-h time

weighted average) forindustrial and constructionworker exposure.

O(35)

I{ the page filmed in thiA inane. iA not aA *eadable..o< legible, alabel,,it iA due to AubAtandand colon on condition oi tht oniginal pagt.

2. Action-Specific ARARs

a. A Discharge Permit from the Pennsylvania Department ofEnvironmental Resources (PADER) Division of Water Quality Management mustbe applied for and.the expected pollutant levels identified if thepotential exists for asbestos to be present in any discharge to surfacewater.

b, The Montgomery County Conservation District requires that a soilerosion control plan be written and implemented for constructionactivities. This plan must be available for review onsite.

c. Asbestos is a solid waste as defined under Pennsylvania'sManagement Act, of July 7, 1980, Act No. 1980-97, 35 P.S. section 691.1 etseq.. Disposal of asbestos and asbestos containing waste at an unpermittedfacility in Pennsylvania is unlawful. Permitted facilities must complywith the Department's rules and regulations governing solid wastemanagement facilities. The. Anyonwealth consistently requires thatasbestos and asbestos containing wastes be disposed at permitted solidwaste management facilities subject to the above Act and the Department'srules and regulations governing solid waste management facilities.

Relevant and appropriate requirements related to slope design,vegetative cover, and surface water control are found in 25 PA Section 273.However, the requirement of a 1-foot clay cap and drainage layer foundunder 25 PA 273,234 is not an appropriate and relevant requirement. Theuse of a low permeability clay cap is not appropriate for the same reasonsthat a RCRA cap is not appropriate for the CertainTeed Pile site.Semipeneable cover material provides more effective protection frompotential airborne releases of asbestos by maintaining some moisturecontent ia,,the waste naterial,

25 PA 273.234 requires that thi final slopes of a landfill covermay not exceed a grade of 33 percent. The angle of the side slopes of theCertainTeed Pile average 40 percent grade, Alternative 4 does not providefor modification of the slopes, therefore, this ARAR will not be attained.

(36)

li tht page filmed in thiA inane. iA not aA ntadablt.onltgiblt.aAthiA*:label, it iA due. to AubAtandand colon on condition oi tht oniginal page.. \\

Section 121(d)(4) of CERCLA, 42 U.S.C. Section 9621 (d)(4), identifiesseveral circumstances under which certain ARARs may be waived. Two of thepermissible circumstances are listed below with an explanation of how theyapply to the selected remedy.

- Compliance with this ARAR will result in a greater risk tohuman health and the environment than alternative options(See Section 121(d)(4)(B). In order to achieve a side slopethat does not exceed a 33 percent grade for the waste pile,extensive regrading would be required if the toes of the pilewere to remain in their present position, This would meancutting into the asbestos waste and exposing the asbestoscontaminants below. Such action would pose a serious risk tohuman health and the environment because asbestos fiberswould likely become airborne from the disruption.

- Compliance with this ARAR is technically impracticable from.'an engineerinq"t)lHpective (See Section 121(d)(4)(C).Construction would be a major concern. The angle of the sideslopes could be lessened to close to 33 percent by holding

J the top of the slope constant and placing a soil wedge(thereby expanding the "footprint" of the piles at the bottomof the slopes). However, this could not be performed withoutencroaching on existing structures, including Stuart FanCreek, the Sewer Authority collection system, and potentiallythe railway tracks.

3. Location-Specific ARARs

Th» location-specific ARARs for the CertainTeed Pile basicallyInvolve consideration of the Stuart Fan Creek flood plain and accompanyingwetlands. As shown in Figure 2, the southeastern slope of the CertainTeedFile abuts Stuart Fan Creek.

J'

(37)

AR302I»22

li tht pagt iilntd in thiA inane. iA not aA ntadablt..on Itgiblt.aA thiAlabel, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

o Executive Order 11988 (Floodplain Management) and Executive /-sOrder 11990 (Protection of Wetlands) found at 40 era Part 6,Appendix A require that actions be taken to avoid adverseeffects, minimize potential harm, and restore and preservenatural and beneficial values of wetlands and floodplains.

o A Flood Plain/Stream Encroachment Permit is required by thePADER Bureau of Dams and Waterways for construction oralteration of permanent fill/structures along or in the channelor floodway of any stream; This regulation may be applicable tothe installation of erosion control systems along the southeastslope of the pile.

D. Utilization of Permanent Solutions and AlternativeTechnologies to the Maximum Extent Practicable

The selected alternative's currently the most appropriate solutionfor this operable unit and represents the maximum extent to which permanentsolutions and treatment can be practicably utilized. Q

Of the alternatives that are protective of human health and theenvironment, the selected remedy is the easiest to implement within theshortest time-frame, is most cost-effective and provides the highest levelof short-ten effectiveness.

Bxcavation/offsite disposal and onsite vitrification provide ahigher degree of reduction in toxicity, mobility, or volume and long-teneffectiveness and permanence. However, the short-ten risks for thesealternatives srt unacceptable since the potential for release of asbestoswould brqsits high during the lengthy intrusive activity required for eachof the alternatives.

(38)flR302l,23

U tht pagt filmed in thiA inane iA not aA ntadablt.M legible 04 vlabel, it 4.4 due to AubAtandand colon on condition oi tht oniginal pagt.

E. Preference for Treatment as a Principal ElementoThe selected remedy does not accomplish the statutory preference for

treatment as a principle element of the remedy. Since asbestos cannot becombusted and is chemically inert, a permanent remedy as such cannot beeffectively implemented at this site.

XI. Documentation of Significant Changes

The proposed plan for the CertainTeed Pile site was released forpublic consent on August 18, 1989. The selected remedy, Alternative 4 -Onsite closure, was identified in the Proposed Plan as the preferredalternative. No written or verbal coonents to the Proposed Plan weresubmitted to EPA during the coamnt period. Therefore, no significantchanges to the remedy preferred in the Proposed Plan were necessary.

J

O(39)

H tht page, filmed in thiA inant iA not aA ntadablt..,on.ltgiblt..a4..thi4 : -''label, it iA due to 4ub4tanda«d colon on condition oi tht oniginal pagt.

APPENDIX A

RESPONSIVENESS SUMMARY FOR THEAMBLER ASBESTOS PILES SITE

(SECOND OPERABLE UNIT)AMBLER, PENNSYLVANIA

In accordance with Section 113(k)(2) and 117 of CERCIA, the U.S. >Environmental Protection Agency (EPA) established a 30 day comment periodfrom August 18, 1989 through September 18, 1989 on the Proposed Plan andother site related documents for the Ambler Asbestos Pile (CertainTeedPile) in Ambler, Pennsylvania,

An advertisement was placed in the Ambler Gazette on August 16, 1989announcing the availability ortfie Proposed Plan and the dates of the 30day consult period. The advertisement alto announced that requests warebeing accepted for a public meeting.

EPA contacted Ambler Borough officials before the advertisement waspublished.

During the 30 day consent period EPA received no written or verbalcomsents from the public. In the past, residents wire highly interested inthe Locust Street pile (first operable wit) and interest remains high.However, the lack of comments for thin operable unit say be due to the factthat the locust Street Pile is visible to the public eye, and theCertainTssi file is not visible frost the residential area.

o

(40)

AR3Q2l*25

H tkt page filmed in thiA inant iA not aA ntadablt^on ltgiblt.a4,ihiA :*:label, it iA due to AubAtandand colon on condition oi the original page.

APPENDIX B

fnCOMMONWEALTH OF PENNSYLVANIADEPARTMINT OF ENVIRONMENTAL RESOURCES

fO« Offloe son 2083

Deputy seeretaiy for September 29, 1989InvmrnnemalPreucilon 717-787-3028

Mr, Mwin l. BrioksonRegional AdministratorUSIPA Region ill941 Chestnut luilding'hiladslphia, PA 19107

Mi Ambler Asbestos 8up«tfund 8itaOperable Unit 2, OertainTeod riledraft Record Of Decision (ROD)

Dear Mr. IrioksoniThe draft Record of Decision (as received September 18,

1989) for the Ambler Asbestos, Operable Unit 2, has been reviewedby the Department. It is my understanding that this Record ofDecision will be submitted to you for your approval.

The proposed remedy for the Operable Unit 2,CertainTeed Pile, would include regradlng the plateau, repairingerosion damage, installing erosion control devices, and postclosure monitoring.

I hereby concur with the IPA'S proposed remedy, withthe following conditional

* »A will allure that the Department is provided anopportunity to fully participate in any negotiationswith responsible parties,

* The Department will be given the opportunity to concurwith decisions related to the design of the remedialaction, to assure compliance with DBR design specificARM!.

* The Department'1 position is that its design standardsare ARARs pursuant to SAM lection 131, and we willreserve our right to enforce those design standards.

* ' The Department will reserve our right andresponsibility to take Independent enforcement action.pursuant to state and federal ftj gQ 2 1} 2 6

II tht pagt iilntd in thiA inant iA not aA ntadablt,..on Itgiblt aA thiAlabel, it iA due to AubAtandand colon on condition oi tht oniginal pagt.

Mr, Bdwin B. Brlckson - 2 - September 29, 1989Regional Administrator

* This concurrence with the selected remedial action isnot intended to provide any assurances pursuant to SARASection 104(e)(3).

It you have any questions regarding this matter pleasedo not hesitate to contact me,

.wi. _Deputy fecrotary Q

O

H tkt pagt filmed in thi inant i4 not aA ntadabU,M. leaibl*. «.label, it iA due to 4ub4tanda*d colo< on condition oj the. original page.