cpana baseline voc study final

In the Fall of 2010, the Central Park Area Neighbors Association (CPANA) Board of Directors

responded to citizen concerns about the air quality effects of proposed gas drilling in

Southern Lewisville by approving a study that would undertake some baseline readings of

volatile organic compounds (VOCs) over the course of a full year. The study, which would

hopefully (at the time) be concluded prior to the commencement of gas drilling activity

would give an estimate of the amount of VOCs in the air before gas activity, in order to

provide a basis for comparison after gas activity.

Results SummaryMost of the volatile organic compounds detected in this study were picked up in quantities

less than 0.1 parts per billion (ppb). The highest maximum concentration of any substance

was only 0.49 ppb. The highest concentration for benzene in any given month was 0.27 ppb,

well below the 1.4 ppb long-term effects screening level (LTESL) established by the Texas

Commission on Environmental Quality (TCEQ). The highest monthly VOC load for any given

sample was 1.81 ppb for all substances detected, and averaged only 0.82 ppb. Although the

levels detected were very low, the data suggest a difference between the two general areas

being surveyed, with one area showing about twice the VOC load. In any case, no

compounds came close to any air monitoring comparison values (AMCVs).

Methodology ChosenOther studies conducted around the Barnett shale typically used summa canisters for this,

taking a sample anywhere from 30 minutes to 24 hours. Not only are these tests

prohibitively expensive for the type of study CPANA could afford, but they are hardly

representative of the dynamic nature of wind and the effects of weather, season, and

temperature as they vary over time. Some VOCs may occur naturally, and be seasonal based

on flora and fauna, so we thought it best to get samples that would show a picture of what it

looks like over the course of a year.

The sampling method CPANA chose was the passive diffusion tube. Stainless steel tubes

containing a specially chosen sorbent material were placed at the sampling locations and left

open to the air for periods averaging about a month each. As ambient air diffuses up the

tubes, the sorbent material locks in the contaminants. The tubes are then sent to the

laboratory for analysis using Thermal Desorption - Gas Chromatography / Mass Spectrometry

(TD-GC/MS) In this process, the tubes are heated to force the sorbent to release the

contaminants into a specialized machine that determines the compounds and approximate

concentrations on the tube. Using a formula for the amount of air that diffuses into the tube

over the time period exposed, the approximate average concentration in the air over the

sampling period is calculated.

LaboratoryCPANA utilized Ormantine USA, Ltd., an analytical laboratory company to supply the tubes

and do the analysis on them after exposure. Ormantine was chosen because of their

product and method, and because they have no ties to any of the local gas operators.

Ormantine is affiliated with Gradko Environmental, a UKAS accredited laboratory in England.

Gradko supplies the pre-conditioned diffusion tubes, and analyzes them after exposure.

Gradko's accreditation applies only to the methods they use to determine the mass of the

analytes on the tubes, and not to the parts-per-billion figures calculated based on that mass.

Analytes

CPANA Baseline VOC Study


AnalytesThis study is concerned with VOCs only. Because benzene was a major concern with gas-

related activities in other communities, CPANA wanted a quantitative analysis of benzene

with each sample. In order to get a feel for the other possible compounds in the air, we

asked Ormantine to provide the top nine other compounds (semi-quantitatively, based on

toluene standards) with each sample.

Wind DirectionWind direction and speed measurements were not taken due to the length of the study.

However, wind speed and directional averages for our area are attached. The wind rose

data is from 1984 - 1992, so it is possible that there is an updated version somewhere that

would account for any climate change since then.

Accurate day-by-day wind speed and directional info is available from the TCEQ air

monitoring station in nearby Flower Mound:

http://www5.tceq.state.tx.us/tamis/index.cfm?fuseaction=report.view_site&siteAQS=

481211007

Quality and ReliabilityThe GLM-13 testing method for VOCs, carried out by TD-GC/MS for quantitative analysis

carries an overall Measurement Uncertainty (MU) of +/- 14.42% at 95% confidence. Semi-

quantitative results for the other VOCs were provided using toluene standards, and thus

have more uncertainty.

CPANA sent a blind trip blank (unexposed sample tube) along with one of the true samples,

and did receive three false hits on analyte substances, although all of them were at very low

levels just barely over the limit of detection. Impact is discussed in the "Possible

Shortcomings" section.

SecurityBecause our sampling was very long-term, we were concerned about the possibility of

tampering by the curious or malicious person. For this reason we sought sampling locations

on private property in somewhat controlled areas where it would be unlikely for someone to

happen upon them. The test sites were kept confidential throughout the study to reduce

the chances that someone would attempt to tamper. We also built ventilated steel boxes

that could be padlocked and security-sealed so that any tampering would be evident. The

boxes were screened to prevent insect entry. At each and every installation or removal of a

sample tube, a strict protocol was followed requiring at least one CPANA board member, and

a witness. During the study, no signs of tampering were observed. The boxes were checked

for signs of insects at each opening.

A strict chain of custody was observed, beginning with the shipment of sample tubes to

CPANA, which would stay sealed in the shipping container until ready for installation. Serial

numbers were observed and recorded upon opening, installation, and retrieval. Completed

samples were processed under witness, and mailed from the U.S. Post Office in Lewisville

each time with at least one board member and one witness, who was most often another

board member.

Possible ShortcomingsCPANA's board members are not environmental engineers. As such, we may have missed

something in our methodology. No study is perfect, but it's important to lay out any possible

shortcomings openly and honestly for objective evaluation. Here are the possible


There was a general lack of experience and credentials of the volunteers conducting

the study.

•

Possible over-exposure of the tubes on several occasions when we could not round up

volunteers to retrieve tubes.

•

Security enclosures could have affected airflow to the sample tubes in ways that we do

not understand. We felt that with the very tiny amount of air diffusion expected in the

tubes, and the very long periods of exposure, any effects of slow air exchange in the

enclosure would average out.

•

Our security would not have been able to defeat all possible avenues of tampering -

either in temporarily blocking vents to cause under-reporting or in maliciously

releasing contaminants in proximity to the sample tubes to cause over-reporting. This

would be true of any air sampling method that did not involve having a watchman on

the sample 24/7.

•

A blind trip blank's analysis at the end of the study came back showing three low-level

hits on analyte substances. The hits were just barely above the limit of detection, but

do serve as a reminder that there is a level of measurement uncertainty, especially at

the very low levels.

•

In only one sample, a housefly was observed as the box was opened, but we couldn't

be sure of whether it was in the box. The screening material around the vents was

intact.

•

shortcomings openly and honestly for objective evaluation. Here are the possible

shortcomings that could skew the results of this study in one direction or another:

Comparison ValuesCPANA used TCEQ AMCVs where available, and long-term ESLs where AMCVs were not

otherwise available. These AMCVs would indicate a level which if reached would cause

concern based on health. As mentioned before, no compounds were detected above

AMCVs. Some compounds had no AMCVs or LTESLs, and are shown with N/A in the AMCV

column. This may be because the compound is considered harmless, or it may be that there

is no data on the compound. In some cases, TCEQ LTESLs were expressed in micrograms per

cubic meter (µg/m3). In these cases, for consistency, a formula was used to convert this into

ppb.

Questions and ConcernsAnyone with questions or concerns about this study can contact CPANA Board Member

Steve Southwell: 469-322-4265 or [email protected]

Air Sample History - Dates and Times SampledA.

Sampling LocationsB.

Compounds DetectedC.

VOC Chart - Benzene, Toluene, Total VOC LoadD.

Sample LogsE.

ORM VOC Tech sheetF.

Laboratory ResultsG.

Wind Roses - Average by MonthH.

Documents Attached


CPANA Air Sample History

Sample # Month Box # Tube Start Date

Start Time End Date

End Time

Hours Exposed

Total Minutes

Mailed to Lab Analyzed

Results Rec'd Witness1 Witness2 Witness1 Witness2

1 2010-Jun 210 GRA 05812 6/23/10 19:14 7/24/2010 9:54 734.67 44080 7/24/2010 8/10/2010 8/16/2010 Turner McMahon Turner Southwell2 2010-Jul 210 GRA 05590 7/24/2010 10:00 8/19/2010 19:00 633.00 37980 8/19/2010 8/27/2010 8/31/2010 Southwell McMahon McMahon Southwell3 2010-Aug 210 GRA 05840 8/19/2010 19:10 9/19/2010 11:15 736.08 44165 9/19/2010 9/30/2010 10/5/2010 Southwell McMahon Southwell Ferguson4 2010-Sep 210 MI 058214 9/19/2010 20:10 10/18/2010 17:37 693.45 41607 10/18/2010 11/3/2010 11/5/2010 Southwell Ferguson Southwell Turner5 2010-Oct 210 GRA 05809 10/18/2010 17:45 11/16/2010 17:10 695.42 41725 11/16/2010 12/16/2010 12/17/2010 Southwell Turner Southwell Turner6 2010-Nov 210 GRA 05527 11/16/2010 17:12 12/18/2010 10:23 761.18 45671 12/18/2010 1/12/2011 1/13/2011 Southwell Turner Patterson Southwell7 2011-Jan 185 GRA 08714 1/3/2011 17:07 2/5/2011 15:20 790.22 47413 2/5/2011 2/22/2011 2/23/2011 Turner Southwell Southwell Ferguson8 2011-Feb 185 GRA 01395 2/5/2011 15:28 3/5/2011 11:33 668.08 40085 3/5/2011 3/15/2011 3/21/2011 Southwell Ferguson Southwell McMahon

9a 2011-Mar 210 MI 014095 3/5/2011 11:40 4/7/2011 18:07 798.45 47907 4/7/2011 4/26/2011 4/28/2011 Southwell McMahon Southwell Ferguson9b 2011-Mar 99 mi 43634 3/5/2011 12:49 4/7/2011 18:30 797.68 47861 4/7/2011 4/26/2011 4/28/2011 McMahon Southwell Southwell Ferguson

10a 2011-May 210 GRA05842 5/10/2011 17:21 6/10/2011 16:19 742.97 44578 6/10/2011 6/16/2011 6/28/2011 Turner Southwell Turner Southwell10b 2011-May 99 GRA05540 5/10/2011 17:35 6/10/2011 16:05 742.50 44550 6/10/2011 6/16/2011 6/28/2011 Turner Southwell Turner Southwell11 2011-Jun 210 Mi143657 6/10/2011 16:23 7/7/2011 19:51 651.47 39088 7/7/2011 7/25/2011 8/1/2011 Southwell Turner Southwell Turner

11b 2011-Jun Blank Mi143643 6/10/2011 - 7/7/2011 - 651.47 39088 7/7/2011 7/25/2011 8/1/2011 Southwell - Southwell Turner

*Blank is a trip blank, held unexposed while an identical tube was exposed in the field. Trip blank is sent back to the lab as if it's an actual sample, and the lab doesn't know in advance.

Witnesses:

Placement Retrieval

Steve Southwell, CPANA Board MemberAnne McMahon, CPANA Board MemberR.Neil Ferguson, LNRUD PresidentDarrell Patterson, CPANA Board Member

CPANA Sampling Locations

For the purpose of the benchmark air quality study, CPANA chose locations within its constituent area in Southern Lewisville that it felt represented a possible worst case scenario for any future emissions from natural gas drilling

Because our sampling is done passively through an unattended device, and CPANA desires to keep the locations of these devices secure to avoid tampering, we have listed on this sheet only general areas in which we've placed our boxes. Each box has a number, and that box number is unique to a fixed location, which does not change from

This map shows the approximate locations of our sampling boxes.

Exact locations of the samples will be disclosed to appropriate governmental entities in the event that investigation is necessary, or upon the end of our testing.

Box 210: East of Valley Parkway, North of Corporate Drive, West of Regency Drive, South of Timber Creek.Box 185: East of Valley Parkway, South of Corporate Drive, West of Briarcliff, North of Holly Lane.Box 99: Within 500 feet of the proposed B&H well site on Southwest Parkway, West of S.H. 121 Business.

CPANA Air Quality Benchmark1 2 3 4 5 6 7 8 9a 9b 10a 10b 11 11b

Compound Box: 210 210 210 210 210 210 185 185 210 99 210 99 210 Blank Average* Max PPB AMCV AMCV Source Notes0.23 0.23 0.23 200 TCEQ LTESL

0.19 0.19 0.19 - N/A No AMCV found0.03 0.15 0.30 0.03 0.07 0.12 0.30 51.37 TCEQ LTESL 350 ug/m3 (Calculated ppb)0.03 0.29 0.02 0.07 0.04 0.09 0.29 - N/A No AMCV found0.15 0.15 0.15 10 TCEQ LTESL

0.03 0.06 0.27 0.23 0.16 0.10 0.19 0.07 0.06 0.18 0.14 0.27 1100 TCEQ0.13 0.13 0.13 20 TCEQ LTESL

0.19 0.19 0.19 250 TCEQ0.16 0.16 0.16 100 TCEQ

0.03 0.04 0.13 0.32 0.15 0.49 0.19 0.49 47.46 TCEQ LTESL 350 ug/m3 (Calculated ppb)<LOD 0.08 <LOD (0 0.27 <LOD 0.10 0.06 0.11 0.16 0.10 0.03 0.03 0.27 0.06 0.12 0.27 1.4 TCEQ Benzene LOD 3.9 ng/tube

0.07 0.15 0.11 0.15 55 TCEQ0.15 0.14 0.07 0.04 0.10 0.15 63 TCEQ

0.06 0.10 0.08 0.10 25 TCEQ0.10 0.04 0.05 0.06 0.10 38.64 TCEQ LTESL 350 ug/m3 (Calculated ppb)

0.13 0.06 0.07 0.07 0.08 0.13 5 TCEQ0.02 Iso Iso 0.21 0.15 0.07 0.07 0.04 0.09 0.04 0.05 0.08 0.21 140 TCEQ

0.09 0.09 0.09 1000 TCEQ0.06 0.15 0.02 0.08 0.15 25 TCEQ

0.05 0.11 0.11 0.09 0.11 800 TCEQIso 0.06 0.10 Iso Iso Iso Iso Iso Iso 0.08 0.10 42 TCEQ

0.06 0.05 0.06 0.06 1.04 TCEQ LTESL 10 ug/m3 (Calculated ppb)0.03 0.08 0.20 0.10 0.20 120 TCEQ A.K.A. isopentane

0.07 0.04 0.04 0.05 0.07 85 TCEQ0.05 0.05 0.05 75 TCEQ

0.05 0.09 0.07 0.09 190 TCEQ0.05 0.05 0.05 0.98 TCEQ LTESL 10 ug/m3 (Calculated ppb)

0.07 0.03 0.04 0.05 0.07 75 TCEQ0.05 0.06 0.03 0.05 0.06 140 TCEQ

0.03 0.03 0.08 0.07 0.21 0.08 0.21 44.11 TCEQ LTESL 350 ug/m3 (Calculated ppb)0.04 0.04 0.04 - N/A No AMCV found

0.04 0.04 0.04 - N/A No AMCV found0.06 0.02 0.03 0.02 0.03 0.06 100 TCEQ

0.03 0.03 0.03 400 TCEQ LTESL0.02 0.02 0.02 175 TCEQ

0.04 0.04 0.04 800 TCEQ LTESL0.04 0.00 0.00 51 TCEQ LTESL 350 ug/m3 (Calculated ppb) - AKA Isododecane0.02 0.00 0.00 1 TCEQ LTESL

0.04 0.04 0.04 - N/A No AMCV found0.03 0.09 0.06 0.09 - N/A No AMCV found

0.02 0.04 0.03 0.04 75 TCEQ0.20 0.73 0.77 1.25 0.52 0.66 0.49 0.19 0.93 1.81 0.55 1.19 1.33 0.12 0.82 1.81 -

Notes:Light Blue BTEX Compounds - Benzene, Toluene, Xylene, EthylbenzeneBlank Not in the top 9 compounds other than benzene detected for that sample

<LOD = Analyzed for, but below limits of detection. Iso = The compound is shown elsewhere as a different isomer, or non-specific isomer group.Average* when detected.

Samples - results in ppb

Isopropyl AlcoholCyclohexane, isothiocyanato-

DodecaneCyclohexane, isocyanato-

Acetic AcidToluene

Cyclohexanone

TridecaneBenzene

Undecane1R-alpha-pinene

Benzene, 1,2,3-trimethyl-

Benzene, 1,2,4-trimethyl-Butane

p-Xylene

HexadecanePhenol

m/p-XyleneDichlorodifluoromethane

OctadecaneOctane

HeptadecaneButane, 2-methyl

Heptane

Total VOC Loads (ppb)

EthylbenzeneCyclohexane, methyl

DecaneIsobutane

Benzothiazole

Heptane, 2,2,4,6,6-pentamethylCarbon Disulfide

AcetonePentane, 2-methyl

Ethanol

Hexane, 3 Methyl

o-XyleneTetradecane

1,4-Methanoazulene, decahydro-4,8,8Pentadecane

2,3,4-trimethylpentaneHexane

Volatile Organic Compounds - CPANA Baseline Study

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

2.00

1 2 3 4 5 6 7 8 9a 9b 10a 10b 11

Sample Number

Part

s pe

r bill

ion

Total VOC LoadsBenzeneToluene

Technical Data Sheet: TDS 8 VOLATILE ORGANIC COMPOUNDS (VOCs) Passive Sampler and Active (pumped) Sampler Tubes This tube is designed for passive (time weighted average concentrations) and active (pumped) sampling of volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) in the carbon range of C2 – C32. The tube can be used passively for time weighted average concentrations, or pumped (active) for indoor and outdoor monitoring, or for workplace monitoring and comparison to health and safety workplace exposure limits.

Description: Stainless steel tube filled with a solid polymer absorbent and two brass swagelock caps. For passive sampling an aluminium air diffuser is supplied (attached to bottom of tube in above photograph) which is fitted to the sampling end of the tube (groove end) during exposure, by replacing the brass nut. For active sampling, both brass nuts are removed, and an air pump set to 50 ml/min, is connected to the non-sampling end (non-groove end) of the tube and run for a preset period. Suitable for carrying out spatial or localized assessments of volatile and semi-volatile organics in ambient air, soil, workplace, or industrial monitoring. Can be used for measuring VOCs and SVOCs in soil using a borehole or a soil probe (see Technical Sheet TDS 11). Tube Dimensions: 6.3mm OD x 5.0mm ID x 90mm length. An appropriate sorbent is selected to suit the application required (See Page 2, below). Concentrations absorbed by the tube are measured by thermal desorption and analysis by Gas Chromatography with Flame Ionization Detection (GC/FID) or by Gas Chromatography/Mass Spectroscopy (GC/MS). Both methods are U.K.A.S. accredited. Recommended Exposure Periods for Passive Sampling: 1–4 weeks. For Active Sampling the safe sampling volumes for each type of compound to be monitored should be considered (published figures). Uptake Rates: Determined by calibration in a standard atmosphere or quoted from published data. Air Velocity: Tube fitted with filter therefore negligible influence. Storage: Store in a dark, cool environment free from residual airborne VOC. Shelf Life: 12 weeks from conditioning date dependant on type of solid sorbent used. Desorption Efficiency: d = 0.99 (determined using N.I.S.T. Standard Analytes). Analytical Expanded Measurement Uncertainty: +/- 14.8%. Limit of Detection (LOD: Analysis): 0.2 ppb.

Technical Data Sheet: TDS 8 VOLATILE ORGANIC COMPOUNDS Relevant Standards : ISO16017 : EN14662 : EN13528: EPA T0-17 Applications:

• Ambient Air Monitoring of Traffic Systems, Factory Outputs such as Paint Shops, Petrochemical Boundaries. • Stack monitoring. • Workplace monitoring: Measuring levels of airborne solvent vapors. • Personal Monitoring • Soil Monitoring • Measurement of Occupational Exposure Levels • Biological Monitoring i.e. Non-invasive measuring of levels of VOCs taken into the

body by skin adsorption, ingestion and inhalation. This method provides vital information on the potentially harmful build-up of chemicals in the body after prolonged low-level exposure.

Packaging Of Sorbents: Each type of sorbent is packed into the thermal desorption tube under strict quality control and under laboratory environment conditions. The weight of the sorbent packed is controlled to within +/- 5%. Selection of Absorbents: The choice of absorbent depends on the volatility of the analyte concerned. Sorbents or series of sorbents selected must quantitatively retain the compounds from the volume of air/gas sampled and then be released as efficiently as possible when the tube is desorbed. A general rule is to use the boiling point of the component as a guide to its volatility. The more volatile the analyte, the stronger the sorbent must be. For further information, please contact our Technical Dept at Ormantine USA Ltd. Inc. Tel. 321 676 7003 Fax. 321 676 7699 E-Mail : sales @ormantineusa.com

Wind Roses for DFW Area