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Final Data Usability Summary Report Bandera Road Ground Water Plume Site

Leon Valley, Bexar County, Texas Remedial Action Contract 2 Full Service

Contract: EP-W-06-004 Task Order: 0023-RIRI-06TY

Prepared for

U.S. Environmental Protection Agency Region 6

1445 Ross Avenue Dallas, Texas 75202-2733

Prepared by

EA Engineering, Science, and Technology, Inc. 405 S. Highway 121 Building C, Suite 100

Lewisville, Texas 75067 (972) 315-3922

December 2008 Revision: 01

EA Project No. 14342.23

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EA Project No. 14342.23 Revision: 01 Contents, Page 1 of 1 EA Engineering, Science, and Technology, Inc. December 2008

Bandera Road Ground Water Plume Site Final Data Usability Summary Report Leon Valley, Bexar County, Texas Ground Water Investigation

CONTENTS Page

1. INTRODUCTION .....................................................................................................................1

2. GROUND WATER DATA SUMMARY .................................................................................2 2.1 NOVEMBER 2007 SAMPLING EVENT..........................................................................2 2.2 JANUARY 2008 SAMPLING EVENT .............................................................................2 2.3 APRIL 2008 SAMPLING EVENT ....................................................................................3 2.4 JULY 2008 SAMPLING EVENT ......................................................................................4 2.5 SEPTEMBER 2008 SAMPLING EVENT .........................................................................4 2.6 OCTOBER 2008 SAMPLING EVENT .............................................................................5

3. DATA VALIDATION ...............................................................................................................6

4. DATA QUALITY ......................................................................................................................7 4.1 NOVEMBER 2007 SAMPLING EVENT..........................................................................7 4.2 JANUARY 2008 SAMPLING EVENT .............................................................................7 4.3 APRIL 2008 SAMPLING EVENT ....................................................................................8 4.4 JULY 2008 SAMPLING EVENT ......................................................................................8

4.4.1 VOC Sample Evaluation ..........................................................................................8 4.4.2 HydraSleeveTM Sample Collection and PDB Sample Collection Comparison ........9 4.4.3 MNA Samples ..........................................................................................................9

4.5 SEPTEMBER 2008 SAMPLING EVENT .........................................................................9 4.6 OCTOBER 2008 SAMPLING EVENT ...........................................................................10

5. DATA EVALUATION ...........................................................................................................11 5.1 PRECISION .....................................................................................................................11

5.1.1 November 2007 Sampling Event ...........................................................................11 5.1.2 January 2008 Sampling Event ................................................................................11 5.1.3 April 2008 Sampling Event ....................................................................................11 5.1.4 July 2008 Sampling Event......................................................................................12 5.1.5 September 2008 Sampling Event ...........................................................................12 5.1.6 October 2008 Sampling Event ...............................................................................12 5.1.7 Quality Assurance/Quality Control Sample Frequency .........................................12

5.2 ACCURACY ....................................................................................................................12 5.3 REPRESENTATIVENESS ..............................................................................................13 5.4 COMPLETENESS ...........................................................................................................13 5.5 COMPARABILITY .........................................................................................................13 5.6 SENSITIVITY .................................................................................................................14

6. CONCLUSIONS......................................................................................................................15

7. REFERENCES ........................................................................................................................16 ATTACHMENT A DATA VALIDATION REPORT SUMMARIES ATTACHMENT B EON PRODUCTS INFORMATIONAL MATERIAL

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EA Project No. 14342.23 Revision: 01 List of Tables, Page 1 of 1 EA Engineering, Science, and Technology, Inc. December 2008


LIST OF TABLES

Number Title

1 November 2007 Residential and Municipal Well Water Sampling Information

2 November 2007 Ground Water Sampling Data Summary (Detected Analytes)

3 January 2008 Residential Passive Diffusion Bag and Municipal Well Water Sampling Information

4 January 2008 Ground Water Sampling Data Summary (Detected Analytes)

5 April 2008 Passive Diffusion Bag Private Well Sampling

6 April 2008 Private and Municipal Well Water Sampling Information

7 April 2008 Ground Water Sampling Data Summary (Detected Analytes)

8 July 2008 Passive Diffusion Bag Private Well Sampling

9 July 2008 HydraSleeveTM Sampling Information

10 Private and Municipal Well Water Sampling

11 July 2008 Ground Water Sampling Data Summary (Detected Analytes)

12 Municipal Well Water Sampling Information

13 Passive Diffusion Bag and HydraSleeveTM Analyte Concentration Comparison at USGS-42

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EA Project No. 14342.23 Revision: 01 Page 1 of 16 EA Engineering, Science, and Technology, Inc. December 2008


1. INTRODUCTION

This Data Usability Summary Report (DUSR) presents the results of the ground water sampling conducted by EA Engineering, Science, and Technology, Inc. (EA) for the Bandera Road Ground Water Plume Superfund Site (Site) located in Leon Valley, Bexar County, Texas. EA prepared this DUSR for the U.S. Environmental Protection Agency (EPA) Region 6 as part of Task Order No. 0023-RIRI-06TY under EPA Contract EP-W-06-004.

This DUSR was completed for private and municipal ground water well samples collected during remedial investigation (RI) activities conducted during the November 2007, January 2008, April 2008, July 2008, September 2008, and October 2008 ground water sampling events. Data collection activities were conducted in accordance with the EPA-approved RI Work Plan (EA 2007a) and Sampling and Analysis Plan (SAP) (EA 2007b).

The purpose of this document is to summarize analytical data quality and usability in relation to the project-specific data quality objectives (DQOs). A ground water data summary compiling, tabulating, and summarizing the data collected during the RI activities is provided in Section 2.0. Data validation guidelines, responsibilities, and results are addressed in Section 3.0. Data quality, which includes a discussion of discrepancies and data quality issues, is presented in Section 4.0. A data evaluation is presented in Section 5.0, and conclusions are presented in Section 6.0. References are provided in Section 7.0. Supporting tables follow the text.

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2. GROUND WATER DATA SUMMARY

This section contains a summary of private and municipal ground water well sampling data collected during RI activities.

The six ground water sampling events that were conducted occurred in November 2007, January 2008, April 2008, July 2008, September 2008, and October 2008 and are the focus of this DUSR. Ground water data were collected to characterize the nature and extent of impacted ground water at the Site. The ground water sampling events were discussed separately throughout this document for clarity.

2.1 NOVEMBER 2007 SAMPLING EVENT

During the November 2007 sampling event, 27 private water wells, two municipal water wells, and one 55-gallon drum of investigation-derived waste (IDW) were sampled as detailed in Table 1. Samples were analyzed for volatile organic compound (VOC) analysis, semi-volatile organic compound (SVOC) analysis, and inorganics analysis as prescribed by the RI Work Plan (EA 2007a) and SAP (EA 2007b).

The two municipal water well samples were analyzed for VOCs, SVOCs, and inorganics. Private water wells were analyzed for VOCs and inorganics. In addition, the private water wells that met the criteria for an observed release of tetrachloroethene (i.e., detection above the laboratory method detection limit in historical samples) were also analyzed for SVOCs. The drum of IDW (identified as DECON-1), which contained decontamination water, was analyzed for VOCs. The collection of ground water samples, including field duplicates and quality assurance/quality control samples (QA/QC) is detailed on Table 1.

Samples were analyzed for VOCs and SVOCs using the EPA Contract Laboratory Program (CLP) Statement of Work (SOW) SOM01.2 and for inorganics using CLP SOW ILM05.4. Additional details pertaining to this field event are provided in the Field Activity Report (EA 2007c). Analytes detected in ground water well samples collected as part of the November 2007 sampling event are summarized in Table 2.

2.2 JANUARY 2008 SAMPLING EVENT

During the January 2008 sampling event, 58 passive diffusion bags (PDB) were installed at various depths in 10 private wells as presented in Table 3. It takes approximately two weeks (i.e., 14 days) for organic chemicals (e.g., tetrachloroethene) in the surrounding formation ground water to equilibrate with water in the PDBs; this equilibration occurs when organic compounds pass through the semi-permeable membrane. The PDBs were deployed on 10 January 2008 and retrieved on 28 – 29 January 2008, so the PDBs were allowed to equilibrate in the private water wells for 18 to 19 days. Pre-filled PDBs (i.e., with deionized water) from the vendor (Eon Products, Inc. [Eon]) were utilized during this sampling event.

Ground water samples collected from the PDBs were submitted for VOC analysis. New PDBs were then redeployed in private wells where pumps were not reinstalled for future sampling. In addition, two municipal water wells and one 55-gallon drum of IDW containing decontamination

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water (identified as DECON-2) were sampled as detailed on Table 3. The two municipal water well samples were analyzed for VOCs, SVOCs, and inorganics, while the IDW was sampled and analyzed for VOCs. The collection of ground water samples, including field duplicates and QA/QC samples is detailed on Table 3.

Samples were analyzed for VOCs and SVOCs using the EPA CLP SOW SOM01.2 and for inorganics using CLP SOW ILM05.4, as prescribed by the RI Work Plan (EA 2007a) and SAP (EA 2007b). Additional details pertaining to the January 2008 field event are provided in the Field Activity Report (EA 2008d). Analytes detected in ground water well samples collected as part of the January 2008 sampling event are summarized in Table 4.

2.3 APRIL 2008 SAMPLING EVENT

During the April 2008 sampling event, 23 private tap water wells, two municipal water wells, and seven private wells with PDBs were sampled as detailed in Tables 5 and 6. Samples were analyzed for VOCs, SVOCs, inorganics, 1,4-dioxane, monitored natural attenuation (MNA) parameters (nitrite, nitrate, sulfate, sulfide, chloride, total organic carbon, ammonia, and ortho-phosphate); and methane, ethane, and ethene.

The two municipal water well samples were analyzed for VOCs, SVOCs, inorganics, and 1,4-dioxane. The private water wells were analyzed for VOCs, SVOCs, and inorganics. A select number of private water wells were analyzed for 1,4-dioxane, MNA parameters, and methane, ethane, and ethene. Additionally, during the April 2008 sampling event, 38 PDBs were retrieved from various depths within the private wells as presented in Table 5. The PDBs were deployed on 28 – 29 January 2008 and retrieved on 14 – 15 April 2008, so the PDBs were allowed to equilibrate in the private water wells for 77 to 79 days. Pre-filled PDBs (i.e., with deionized water) from Eon were utilized during this sampling event. Ground water samples collected from the private wells containing PDBs were submitted for VOC analysis. New PDBs were then redeployed into the private wells for future sampling as necessary (see Table 5). The collection of ground water samples, including field duplicates and QA/QC is detailed on Tables 5 and 6.

Ground water samples collected for the April 2008 sampling event were analyzed for VOCs and SVOCs using the EPA CLP SOM01.2 and for inorganics using CLP SOW ILM05.4. Samples were analyzed for 1,4-dioxane using EPA Method 8270, nitrite and nitrate using EPA Method 353.2, sulfate and chloride using EPA Method 300.1, sulfide using EPA Method 376.1, total organic carbon using EPA Method 415.2, ammonia using EPA Method 350.1, ortho-phosphate using EPA Method 365.1, and methane, ethane, and ethene using Method RSK-175 as prescribed by Field Change Form No. 6, which was approved by EPA through Task Order Modification No. 5 dated 28 March 2008. Additional details pertaining to the April 2008 field event are provided in the Field Activity Report (EA 2008e). Analytes detected in ground water well samples collected as part of the April 2008 sampling event are summarized in Table 7.

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2.4 JULY 2008 SAMPLING EVENT

During the July 2008 sampling event, one private tap water well, two municipal water wells and seven wells containing PDBs were sampled as detailed in Tables 8 through 10. Samples were analyzed for VOCs, inorganics, and MNA parameters (nitrite, nitrate, sulfate, sulfide, chloride, total organic carbon, ammonia, and ortho-phosphate).

During the July 2008 sampling event, 17 PDBs were retrieved from various depths within the private wells and sampled for VOCs (see Table 8). An additional ground water sample was collected from private water well USGS-42 using a HydraSleeveTM and analyzed for VOCs, inorganics, and MNA parameters (see Table 9). The two municipal water well samples (USGS-18 and USGS-50) and private water well DW-42 were analyzed for VOCs and inorganics (see Table 10). The collection of ground water samples, which included field duplicates and QA/QC samples, is detailed on Tables 8 through 10.

The PDBs retrieved for sample collection were deployed on 14 – 16 April 2008 and retrieved on 14 – 15 July 2008, so the PDBs were allowed to equilibrate in the private water wells for 91 to 93 days. The PDBs contained lab-grade blank water (i.e., deionized water) provided by the sample container vendor during this sampling event. Ground water samples collected from the PDBs were submitted for VOC analysis. New PDBs were then redeployed in the private wells for future sampling as necessary (see Table 8).

Samples were analyzed for VOCs and SVOCs using the EPA CLP SOW SOM01.2 and were analyzed for inorganics using CLP SOW ILM05.4, as prescribed by the RI Work Plan (EA 2007a) and SAP (EA 2007b). Additionally, samples were analyzed for nitrite and nitrate using EPA Method 353.2, sulfate and chloride using EPA Method 300.1, sulfide using EPA Method 376.1, total organic carbon using EPA Method 415.2, ammonia using EPA Method 350.1, ortho-phosphate using EPA Method 365.1, as prescribed by Field Change Form No. 6, which was approved by EPA through Task Order Modification No. 5 dated 28 March 2008.

Additional details pertaining to the July 2008 field event are provided in the Field Activity Report (EA 2008f). Analytes detected in ground water well samples collected as part of the July 2008 sampling event are summarized in Table 11.

2.5 SEPTEMBER 2008 SAMPLING EVENT

During the September 2008 sampling event, two municipal water wells were sampled as detailed in Table 12. On 10 September 2008, the samples were received at the EPA Region 6 Laboratory, however; the temperature blank had an elevated temperature of 16°C. Because the elevated temperature fell outside of the acceptable range for preservation (i.e., 4°C), the integrity of the samples could not be verified. Therefore, EPA and EA agreed to recollect the samples. However, severe weather conditions, due to Hurricane Ike, forced the EPA Region 6 Laboratory to suspend its sample analysis for approximately two weeks. The next round of Leon Valley municipal well sampling was to occur shortly after the reopening of the laboratory; therefore, EPA directed EA to forgo the sample recollection effort and rely approximately on the October 2008 sample analysis. Although the validity of the samples could not be confirmed, no VOCs were detected in either of the two samples; VOCs have never been detected in either of the

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municipal wells so these results were consistent with historic sampling activities. Additional details pertaining to the September 2008 field event are provided in the Field Activity Report (EA 2008g).

2.6 OCTOBER 2008 SAMPLING EVENT

During the October 2008 sampling event, two municipal water wells were sampled as detailed in Table 12. No VOCs were detected in either of the two samples; VOCs have never been detected in either of the municipal wells so these results were consistent with historic sampling activities. Additional details pertaining to the September 2008 field event are provided in the Field Activity Report (EA 2008g).

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3. DATA VALIDATION

This section describes the data validation guidelines for each type of analytical data provided by the EPA Region 6 Laboratory for SVOCs, VOCs, inorganics, and MNA parameters; methane, ethene, and ethane analysis was conducted by the TestAmerica Laboratory located in Austin, Texas so was not included in the following analysis. Samples analyzed for MNA parameters (nitrite, nitrate, sulfate, chloride, sulfide, total organic carbon, ammonia, and ortho-phosphate) were shipped to EPA Region 6 Laboratory which were then forwarded to the Texas Commission of Environmental Quality’s (TCEQ’s) Houston Laboratory for analysis. Analytical results received from the EPA Region 6 Laboratory were validated by the laboratory and required no further validation by EA. Electronic deliverables submitted to EA by the EPA Region 6 Laboratory contained suitable data validation qualifiers and accompanying data validation summaries. Data validation qualifiers and definitions for the data qualifiers assigned by the EPA Region 6 Laboratory, TestAmerica Laboratory, and the TCEQ Laboratory are presented as follows:

U The analyte was analyzed, but was not detected above the sample quantitation limit.

TB Concentration determined in sample was found to be 10 X less than concentration found in associated trip blank.

J Result is estimated because of outlying quality control parameters.

B Concentration is estimated because of apparent blank contamination.

TQ01 Analyzed after hold time exceeded per customer request.

The following data validation qualifiers and definitions were noted in EPA analytical laboratory reports: U, TB, J, and B. The TQ01 data validation qualifier and definition was noted in the TCEQ Houston Laboratory analytical results.

Data quality, which includes a discussion of discrepancies and data quality issues, is presented in Section 4.0. Attachment A of this DUSR contains the data validation report summaries.

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4. DATA QUALITY

This section describes the data quality, which includes a discussion of discrepancies and data quality issues.

Ground water well samples collected as part of the RI activities were submitted to the EPA Region 6 Laboratory for analysis of SVOCs, VOCs, and inorganics. Samples collected for nitrite, nitrate, sulfate, chloride, sulfide, total organic carbon, ammonia, and ortho-phosphate where sent to EPA Region 6 Laboratory and forwarded by EPA Region 6 Laboratory to the TCEQ Houston Laboratory for analysis. Samples collected for methane, ethene, and ethane analyses were submitted to TestAmerica in Austin, Texas. Attachment A of this DUSR contains the data validation report summaries; the full data validation reports are provided electronically on compact disc with this DUSR. Significant data quality issues are detailed below.

4.1 NOVEMBER 2007 SAMPLING EVENT

Toluene was detected in both field blanks for the November 2007 sampling event. Field Blank #1 was collected at 12:52 p.m. on 12 November 2007 and contained toluene concentration of 2.8 micrograms per liter (µg/L). Field Blank #2 was collected at 1:28 p.m. on 13 November 2007 and contained toluene concentration of 2.0 µg/L. However, these samples were prepared/analyzed almost a week apart at the EPA Region 6 Laboratory, so it is unlikely that toluene was introduced during the laboratory sample preparation/analysis. Given that the concentrations are similar, it is suspected that the triple deionized water used to fill the field blanks may have contained some low-level concentrations of toluene. This is supported by the fact that trip blanks were not impacted with toluene. The impact of toluene in these field blanks is considered negligible and does not adversely impact the quality of the November 2007 sampling data.

4.2 JANUARY 2008 SAMPLING EVENT

Almost all of the sample results from the January 2008 sampling event had J-flagged and TB-flagged laboratory qualifiers for acetone and 2-butanone. The qualifiers assigned to acetone and 2-butanone by laboratory analyses for this sampling event may be attributed to the use of PDBs.

On occasion, PDBs filled with deionized water have yielded positive results for trace amounts of acetone; however, the detection of trace amounts of acetone in analytical results does not necessarily mean that the detected acetone was acquired from ground water at the sampling location. It has been determined that acetone is a common laboratory trace contaminant, which is often identified in deionized water. The acetone may enter into the deionized water via normal laboratory practices involving the use of equipment and/or the possibility of airborne acetone introduction to water.

Passive diffusion bag samplers filled with deionized water containing trace amounts of acetone and 2-butanone tend to remain within the PDBs due to a slow diffusion rate through the membrane. Attachment B of this DUSR contains informational material issued by Eon regarding acetone issues identified in PDBs. The impact of these two common laboratory contaminants is considered negligible and does not adversely impact the quality of the January

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2008 sampling data. Future sampling events will utilize PDBs filled by EA in an environment where acetone and 2-butanone are not present.

4.3 APRIL 2008 SAMPLING EVENT

Four of the seven PDB samples (DW-43, DW-60, USGS-20, and USGS-42) collected during the April 2008 sampling event had J-flagged laboratory qualifiers for acetone for many of the depths sampled. The qualifiers assigned to acetone by laboratory analyses for this sampling event may be attributed to the use of PDBs. As explained in the January 2008 sampling event data quality summary, PDBs filled with deionized water may yield positive results for trace amounts of acetone.

Sample location DW-401 was also identified as a sample location having a J-flagged laboratory qualifier for acetone. Acetone detected in DW-401 may have been introduced into the sample during laboratory practices; due to the fact that acetone is not normally identified in ground water and is a common laboratory artifact.

Acetone was identified in USGS 44-320 by the laboratory to be above the reporting limit of 5.2 µg/L in both vials used for the matrix spike/matrix spike duplicate (MS/MSD). It was not detected in a concentration above the reporting limit (i.e., it was not detected) in the vial used to report the parent sample results.

Sample location USGS-20 was identified as having a J-flagged laboratory qualifier for 2-butanone for the samples obtained from PDBs set at 108 and 128 feet below the top of the well casing.

Laboratory documentation provided in the laboratory narrative for the final analytical report dated 19 May 2008, denotes that acetone and 2-butanone, where reported and qualified as estimated values due to second source verification failure. Both acetone and 2-butanone are considered common laboratory artifacts that do not negatively impact the results of the remaining detected analytes.

4.4 JULY 2008 SAMPLING EVENT

For the July 2008 sampling event several analyses were conducted and evaluated as presented below in the following sections.

4.4.1 VOC Sample Evaluation

Field blank #2 was qualified as blank related (B) due to the presence of the acetone in the associated analysis blank. Toluene identified in USGS-60-200 qualified as trip blank (TB) related due to the analyte being present in the associated trip blanks. However, after review of the data, the toluene noted in USGS-60-200 was determined to be an actual detection.

The PDB sample location depths collected for USGS-42 for the July 2008 sampling event had J-flagged laboratory qualifiers for each of their associated analytes. When the original analysis was performed on USGS-42-135, USGS-42-150 and USGS-42-165, all three samples collected

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had two surrogates outside QC limits (not reported in final analytical report). Reanalyzes were performed on the dilutions using a vial opened on 23 July 2008 to meet requested reporting limits (RLs). The results for the reanalyzed samples using the 23 July 2008 vial are qualified as estimated due to the vial being open. Sample USGS-42-135 had a qualified estimated tetrachloroethene concentration due to inconsistent results found in the vials and surrogate 1, 2-dichloroethane-d4 from the 23 July 2008 sample failed high. Sample USGS-42-90 was identified as having a surrogate toluene that failed low.

4.4.2 HydraSleeveTM Sample Collection and PDB Sample Collection Comparison

Ground water sample collection at USGS-42 consisted of the use of PDBs and five deployments of HydraSleeveTM samplers to a depth of 145 feet below the top of the well casing. The PDBs at USGS-42 were recovered from the following depths: 90, 100, 115, 135, 150, and 165 feet below top of casing. HydraSleeveTM sample collection occurred after all of the PDBs of USGS-42 were recovered and sampled. Passive diffusion bags for USGS-42 were redeployed when the HydraSleeveTM sample collection was completed.

The volatile organic analysis comparison between the HydraSleeveTM sampler deployed into USGS-42 and the installed PDBs were similar at the 135 and 150-foot depth intervals. A comparison of analyte concentrations reported in PDBs and the HydraSleevesTM is provided in Table 13. This analysis was conducted to evaluate the correlation between PDBs, where VOCs must pass through a permeable membrane, and water sampling without membrane pass through. It should be noted that when analytes collected by the HydraSleeveTM were compared to the same analytes collected by PDBs, the HydraSleeveTM analyte would have a higher analytical result. Nevertheless, the correlation between the two sampling methods is consistent, so PDB sampling is considered a very reliable sampling method for the VOCs of concern at the Site.

4.4.3 MNA Samples

Most samples collected for MNA parameters had detectable levels of nitrate, nitrite, chloride, sulfate, ortho-phosphate, sulfide, ammonia, and total organic carbon. Sample USGS-42 and duplicate sample USGS-42D were analyzed after the hold time had expired and were therefore TQ01 qualified.

4.5 SEPTEMBER 2008 SAMPLING EVENT

Samples collected for VOC analysis from the two Leon Valley municipal wells on 9 September 2008 were received at the EPA Region 6 Laboratory with an elevated temperature blank of 16°C. The acceptable preservation temperature of samples analyzed by EPA Region 6 Laboratory is 4°C or below. The possibility of questionable sample integrity due to an unacceptable cooler temperature dictated that the 9 September 2008 samples be recollected during the next sampling event.

Field blank #1 qualified as blank related (B) due to the presence of acetone in the associated analysis blank. Bromomethane was qualified as estimated in the BS1 quality control sample because the concentration reported was slightly above the calibration range.

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4.6 OCTOBER 2008 SAMPLING EVENT

Field blank #1 collected for the 9 October 2008 sampling event had a J-flagged laboratory qualifier for acetone. As mentioned in previous sections, positive results for trace amounts of acetone in analytical results for a sample does not necessarily mean that the detected acetone was acquired from ground water at the sampling location. It has been determined that acetone is a common laboratory trace contaminant, which is often identified in deionized water. The acetone may enter into the deionized water via normal laboratory practices involving the use of equipment and/or the possibility of airborne acetone introduction to water.

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5. DATA EVALUATION

Analytical results were evaluated in accordance with precision, accuracy, representativeness, completeness, and comparability (PARCC) parameters to document the quality of the data and to ensure that the data are of sufficient quality to meet the project objectives. Each of the PARCC parameters is assessed below.

5.1 PRECISION

Precision is the measure of the variability associated with an entire sampling and analysis process. It is the comparison among independent measurements as the result of repeated application of the same process under similar conditions. It is determined by analyzing field duplicate pairs and MS/MSD or matrix duplicate (MD) pairs. Precision is expressed as the relative percent difference (RPD) of a pair of values (or results). Acceptance criteria for analytical methodologies are presented in the SAP (EA 2007b). During the data validation process, field duplicate and MS/MSD or MD results were evaluated for compliance with acceptance criteria for precision for each analytical methodology. RPD evaluations are documented in the data validation reports, which are provided on compact disc with this report.

The SAP (EA 2007b) specifies that 10 percent (one in 10 samples) be submitted as field duplicates to the laboratory. Field duplicate pairs were collected, analyzed, and evaluated for each analysis with detected results. The SAP (EA 2007b) criterion for field duplicate precision is 50 percent RPD.

5.1.1 November 2007 Sampling Event

Of the 30 ground water well samples collected at the Site, three (approximately 10 percent) were designated as a field duplicate samples: DW-40, USGS-30, and DW-31 (see Table 1). All ground water well field duplicates were within 50 percent RPD. The highest RPD was 30 percent for copper in DW-31; the sample concentration was 21.9 µg/L and the field duplicate was 29.7 µg/L.

5.1.2 January 2008 Sampling Event

Of the 60 ground water well samples collected at the Site, seven (approximately 12 percent) were designated as a field duplicate samples: DW-31-320, DW-36-205, USGS-60-355, USGS-18, USGS-44-295, USGS-51-250, and USGS-58-260 (see Table 3). All ground water well field duplicates were within 50 percent RPD. The highest RPD was 8.8 percent for bromoform in DW-36-205; the sample concentration was 28.3 µg/L and the field duplicate was 30.9 µg/L.

5.1.3 April 2008 Sampling Event

Of the 63 ground water well samples collected at the Site, nine (approximately 14 percent) were designated as a field duplicate samples: DW-11, DW-18, DW-19, DW-30, DW-33, DW-39, DW-43-255, USGS-44-295, and USGS-58-340 (see Tables 5 and 6). All ground water well field duplicates were within 50 percent RPD. The highest RPD was identified in one location exhibiting the same RPDs for two different analytes. Sample location DW-39 had a RPD of 18.2

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percent for 1,1-dichloroethene; the sample concentration was 0.6 µg/L and the field duplicate was 0.5 µg/L. The second analyte of DW-39 exhibiting the same RPD of 18.2 percent was trichlorofluoromethane with a sample concentration of 0.6 µg/L and a field duplicate of 0.5 µg/L. Also during the April 2008 sampling event a blind duplicate sample, identified as DW-401, was collected at USGS-42-135. The RPD was conducted for these samples and the findings are as follows: the RPD was 7.0 percent for tetrachloroethene with a sample concentration of 6,170 µg/L for DW-401 (blind duplicate), and a sample concentration of 6,620 µg/L for USGS-42-135 (original sample).

5.1.4 July 2008 Sampling Event

Of the 21 ground water well samples collected at the Site, three (approximately 14 percent) were designated as field duplicate samples: USGS-42 (HydraSleeveTM), DW-42, and USGS-58-375 (see Tables 8 through 10). All ground water well field duplicates were within 50 percent RPD. The highest RPD was 40 percent for ortho-phosphate in USGS-42 (HydraSleeveTM); the sample concentration was 0.02 µg/L and the field duplicate was 0.03 µg/L. The second highest RPD was identified in two separate locations exhibiting similar RPDs. Sample location USGS-58-375 had a RPD of 6.9 percent for methyl tert-butyl ether, the sample concentration was 1.4 µg/L and the field duplicate was 1.5 µg/L. Sample location DW-42 had a RPD of 6.9 percent for tetrachloroethene; the sample concentration was 1.4 µg/L and the field duplicate was 1.5 µg/L.

5.1.5 September 2008 Sampling Event

Analysis of the RPD was not performed on the data collected for the September 2008 sampling event because there were no detected analytes.

5.1.6 October 2008 Sampling Event

Analysis of the RPD was not performed on the data collected for the October 2008 sampling event because there were no detected analytes.

5.1.7 Quality Assurance/Quality Control Sample Frequency

The SAP states that the frequency criteria for MS/MSD or MD pairs is 5 percent for the EPA CLP laboratories or 10 percent for the EPA Region 6 Laboratory. The MS/MSD or MD samples were collected, analyzed, and evaluated for each analysis performed on every sample matrix at the proper frequency.

5.2 ACCURACY

Accuracy is the degree to which a measurement agrees with its true value and is expressed as percent recovery; acceptance criteria for each analytical methodology are stated in the SAP (EA 2007b). By comparing MS/MSD or MD, laboratory control spikes (LCS), and surrogate recoveries to associated QC limits, accuracy is assessed. Through the process of data validation, MS/MSD or MD, LCS, and surrogate recoveries were evaluated for compliance with acceptance criteria for accuracy for each applicable analytical methodology. Evaluations of percent

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recovery are documented in the data validation report summaries, which are provided on compact disc with this report.

Data were validated against CLP QC limits specified in applicable CLP protocols. When recoveries were above or below the QC limits, a bias was assigned to the result. Recoveries above the QC limits were qualified as biased high, while recoveries below the QC limits were qualified as biased low.

5.3 REPRESENTATIVENESS

Representativeness is a qualitative parameter and is defined by the degree to which data accurately and precisely represent a characteristic of a population, parameter variations at a sampling point, or a process or environmental condition. Sample results were evaluated for representativeness by examining items related to sample collection, including chain of custody documentation, sample labeling, collection dates, and condition of the samples upon receipt at the laboratory. Laboratory procedures were also examined, including anomalies reported by the laboratory, either upon receipt of the samples at the laboratory or during analytical processes. Procedures examined included the following: adherence to recommended holding times; calibration of laboratory instruments; adherence to analytical methods; and completeness of data package documentation. Additional details pertaining to the representativeness of the sample result are documented in the data validation narratives, which are provided on compact disc with this report.

Equipment rinsate and laboratory method blank results were evaluated during the data validation process to determine whether equipment decontamination procedures (equipment rinsate) or laboratory conditions (method blanks) affected sample results. Field blank quality control issues were documented in previous sections and will not be repeated here for brevity.

Additional details pertaining to the representativeness of the sample result are documented in the data validation narratives, which are provided on compact disc with this report.

5.4 COMPLETENESS

Completeness is defined as the percentage of measurements judged to be valid. The validity of sample results is determined through the data validation process. All rejected (R-flagged) sample results are considered to be incomplete. Data that are qualified as estimated (J-flagged) or estimated non-detect (UJ-flagged) are considered to be valid and usable.

The number of valid results divided by the number of possible individual analyte results, expressed as a percentage, determines the completeness of the data set. The 90 percent completeness goal stated in the SAP (EA 2007b) was met because there were no rejected (R-flagged) data.

5.5 COMPARABILITY

Comparability of the data is a qualitative parameter that expresses the confidence with which one data set may be compared to another. Comparability of the data is achieved by using standard

001767



methods for sampling and analysis, reporting data in standard units, normalizing results to standard conditions, and using standardized reporting formats and data validation procedures. No method substitutions were observed that reduced the quality of the data for comparison purposes.

5.6 SENSITIVITY

Sensitivity is the measure of the signal from an instrument that represents an actual deflection or response above instrument noise. Analytical sensitivity is measured by the method detection limit or instrument detection limit and reported with the necessary dilution factors, preparation factors, and dry weight factors of an individual sample as the sample quantitation limit. As stated in the SAP (EA 2007b), the required practical quantitation limits for sample analyses are equal to the contract required detection limits for analyses as provided in the EPA CLP protocols.

001768



6. CONCLUSIONS

The impact of toluene in the November 2007 field blanks is considered negligible and does not adversely impact the quality of the sampling data. The January 2008 field blanks did not have detected concentrations of toluene so no additional measures will be taken.

The January 2008 PDB samples, which were filled with deionized water by Eon, contained trace amounts of acetone and 2-butanone. Acetone and 2-butanone tend to retain within the PDB due to a slow diffusion rate through the membrane. Attachment B of this DUSR contains informational material provided by Eon regarding acetone issues identified with the PDBs. The impact of these two common laboratory contaminants is considered negligible and does not adversely impact the quality of the January 2008 sampling data. Future sampling events will utilize PDBs filled by EA in an environment where acetone and 2-butanone are not present.

As mentioned in earlier sections of this DUSR, detected trace amounts of acetone in many of the April 2008 samples may be attributed to the deionized water used to fill the PDBs and has a minimal chance of affecting the data collected.

Sample USGS-60-200 collected during the July 2008 sampling effort was identified by the laboratory as having a suspect detection of toluene; however, after evaluating data for this sample it was determined that the toluene was an actual detection.

Also during the July 2008 sampling effort a comparison was conducted in well USGS-42 between the PDBs and HydraSleeveTM samplers used to collect water samples from similar depths. This comparison indicated similar analytical results for VOCs in both types of sampling methods. It should be noted that when analytes collected by the HydraSleeveTM were compared to the same analytes collected by PDBs, the HydraSleeveTM analyte would have a higher analytical result.

Samples collected for VOC analysis from the two Leon Valley municipal wells on 9 September 2008 were received at the EPA Region 6 Laboratory with an elevated temperature blank of 16°C. The acceptable preservation temperature of samples analyzed by EPA Region 6 Laboratory is 4°C or below. The possibility of questionable sample integrity due to an unacceptable cooler temperature dictated that the 9 September 2008 samples be recollected during the next sampling event. Although the validity of the samples could not be confirmed, no VOCs were detected in either of the two samples; VOCs have never been detected in either of the municipal wells so these results were consistent with historic sampling activities.

Many samples collected during the October 2008 sampling effort had trace amounts of acetone. As mentioned previously the acetone detection may be attributed to the deionized water used to fill the PDBs or may have possibly been introduced at the laboratory. It is believed that these trace amounts of acetone have a minimal chance of affecting the data collected.

Data quality issues identified in this DUSR are considered negligible and do not significantly impact the quality of the data collected for RI activities.

001769

EA Project No. 14342.23 Revision: 01

Page 16 of 16 EA Engineering, Science, and Technology, Inc. December 2008


7. REFERENCES

EA Engineering, Science, and Technology, Inc. (EA). 2007a. Remedial Investigation Work Plan. Bandera Road Ground Water Plume Site, Leon Valley, Bexar County, Texas. September.

EA. 2007b. Sampling and Analysis Plan. Bandera Road Ground Water Plume Site. Leon Valley, Bexar County, Texas. October.

EA. 2007c. Field Activity Report. Ground Water Investigation (28 October ; 13 November 2007). December.

EA. 2008d. Field Activity Report. Ground Water Investigation (7 – 29 January 2008). February.

EA. 2008e. Field Activity Report. Ground Water Investigation (14 – 17 April 2008). May.

EA. 2008f. Field Activity Report. Ground Water Investigation (14 – 15 July 2008). July.

EA. 2008g. Field Activity Report. Ground Water Investigation (9 September; 9 October 2008). December.

001770

EA Project No. 14342.23 Revision: 01 EA Engineering, Science, and Technology, Inc. December 2008


TABLES

001771

Sample ID (2) Date TimeVolatile Organic

Compound Analysis

Semi-Volatile Organic

Compound Analysis

Inorganic Analysis

DW-10 11/12/2007 1536 X -- XDW-108 11/13/2007 1233 X -- XDW-11 11/12/2007 945 X -- X

DW-11C (1) 11/12/2007 1010 -- -- XDW-117 11/12/2007 1439 X -- XDW-16 11/12/2007 1202 X -- XDW-18 11/12/2007 1336 X -- XDW-19 11/12/2007 1540 X -- X

DW-200 11/12/2007 1717 X -- XDW-201 11/13/2007 933 X -- XDW-21 11/12/2007 1045 X -- X

DW-31 (4) 11/13/2007 1522 X X XDW-33 11/13/2007 1316 X -- XDW-35 11/13/2007 846 X -- XDW-36 11/13/2007 1148 X X XDW-37 11/13/2007 1340 X X X

DW-38 (3) 11/13/2007 1015 X -- XDW-39 (3) 11/12/2007 1142 X X XDW-40 (4) 11/12/2007 1233 X -- XDW-42 (3) 11/13/2007 1101 X X X

DW-44 11/13/2007 1235 X X XDW-46 11/13/2007 1612 X -- XDW-47 11/13/2007 1725 X X XDW-52 11/12/2007 858 X -- X

DW-60 (3) 11/12/2007 938 X -- XUSGS-21 11/13/2007 1412 X -- XUSGS-3 11/12/2007 1036 X -- X

USGS-30 (4) 11/12/2007 1621 X -- XUSGS-18 11/13/2007 1005 X X XUSGS-50 11/13/2007 1052 X X XDECON-1 11/13/2007 1405 X -- --

Notes:

TABLE 1 NOVEMBER 2007 RESIDENTIAL AND MUNICIPAL WELL WATER SAMPLING

INFORMATION

(1) Two residential well samples were collected at DW-11. DW-11 was collected prior to the water filter and DW-11C was collected from the tap after the water filter.(2) All samples were collected from residential wells at or close to the pump as described in the field notes except for USGS-18 and USGS-50, which were collected from the City of Leon Valley municipal wells, and DECON-1, which was collected from the drum of investigation derived waste decontamination water.(3) Sample locations DW-38, DW-39, DW-42, and DW-60 were designated as laboratory quality assurance/quality control samples.(4) Sample locations DW-31, DW-40, and USGS-30 were designated as field duplicate samples.-- = Not Applicable

Page 1 of 1001772

Analyte (1) UnitsLocation of Maximum

Concentration

Detection Frequency

Range of Reporting

Limits1,1-Dichloroethene 0.7 0.7 µg/L DW-39 1 / 29 0.5 - 0.5

Acetone 9.9 J 9.9 J µg/L DW-36 1 / 29 5.0 - 5.0Aluminum 1,140 1,140 µg/L DW-44 1 / 30 100 - 100

Barium 29.4 210 µg/L DW-44 30 / 30 --Bis(2-ethylhexyl)phthalate 6.5 7.1 µg/L DW-31 1 / 9 4.7 - 5.0

Bromodichloromethane 13.4 13.4 µg/L DW-36 1 / 29 0.5 - 0.5Bromoform 4.5 4.5 µg/L DW-36 1 / 29 0.5 - 0.5

Calcium 67,400 159,000 µg/L DW-40 30 / 30 --Carbon tetrachloride 0.8 J 0.8 J µg/L DW-36 1 / 29 0.5 - 0.5

Chloroform 39 39 µg/L DW-36 1 / 29 0.5 - 0.5Chloromethane 0.6 3.3 J µg/L DW-36 2 / 29 0.5 - 0.5

cis-1,2-Dichloroethene 0.6 2.0 µg/L DW-47 3 / 29 0.5 - 0.5Copper 21.9 100 µg/L DW-11C 7 / 30 20.0 - 20.0

Dibromochloromethane 11.7 11.7 µg/L DW-36 1 / 29 0.5 - 0.5Iron 25.8 8,060 µg/L DW-31 18 / 30 25.0 - 25.0Lead 2.1 8.3 µg/L DW-31 7 / 30 2.0 - 2.0

Magnesium 4,160 16,900 µg/L DW-200 30 / 30 --Manganese 5.5 228 µg/L DW-46 7 / 30 5.0 - 5.0Potassium 1,220 2,970 µg/L DW-47 30 / 30 --

Sodium 8,870 84,700 µg/L DW-40 30 / 30 --Tetrachloroethene 0.6 23.2 µg/L DW-37 5 / 29 0.5 - 0.5

Toluene 18.2 137 µg/L DW-31 2 / 29 0.5 - 0.5Trichloroethene 0.8 1.3 µg/L DW-47 4 / 29 0.5 - 0.5

Trichlorofluoromethane 0.9 0.9 µg/L DW-10 1 / 29 0.5 - 0.5Zinc 27.7 2,890 µg/L DW-38 21 / 30 20.0 - 20.0

Notes:µg/L - Micrograms per liter(1) Sample DECON-1 was not included in the data summary because it is not a ground water sample.

TABLE 2 NOVEMBER 2007 GROUND WATER SAMPLING DATA SUMMARY

(DETECTED ANALYTES)

Minimum Concentration

(Qualifier)

Maximum Concentration

(Qualifier)

Page 1 of 1

001773

Sample ID Passive Diffusion Bag Placement(feet below ground surface) Date Time

Volatile Organic Compound

Analysis


Compound Analysis

Inorganic Analysis

DW-36 (3) 110; 155; 165; 175; 190; 205 1/28/2008 0817 X -- --

DW-37 180; 205; 227; 288; 320; 340 1/28/2008 1020 X -- --

DW-31 (2, 3) 170; 210; 245; 285; 320; 340 1/28/2008 1205 X -- --

DW-30 (2) 210; 305; 335; 350; 410; 425 1/28/2008 1300 X -- --

DW-43 (2, 4) 90; 160; 180; 210; 255 1/28/2008 1438 X -- --

USGS-60 (3, 4) 200; 250; 355; 370; 378; 388 1/28/2008 1602 X -- --

USGS-58 (3, 4) 120; 210; 260; 290; 340; 375 1/29/2008 0800 X -- --

DW-44 90; 130; 150; 170; 185 1/29/2008 0920 X -- --

USGS-51 (3, 4) 125; 200; 250; 290; 370; 385 1/29/2008 1208 X -- --

USGS-44 (3, 4) 240; 295; 320; 390; 425; 455 1/29/2008 1354 X -- --

USGS-18 (3) -- 1/29/2008 1030 X X X

USGS-50 (2) -- 1/29/2008 1106 X X X

DECON-2 -- 1/29/2008 1530 X -- --

Notes:

(4) Passive diffusion bags were redeployed in the residential well for future sampling as necessary.

TABLE 3JANUARY 2008 RESIDENTIAL PASSIVE DIFFUSION BAG AND MUNICIPAL WELL WATER SAMPLING INFORMATION

(1) All samples were collected from passive diffusion bags deployed in residential wells as described in the field notes except for USGS-18 and USGS-50, which were collected from the City of Leon Valley municipal wells, and DECON-2, which was collected from the drum of investigation derived waste decontamination water.(2) Sample locations DW-31-285, DW-43-255, DW-30-305, and DW-50 were designated as laboratory quality assurance/quality control samples.(3) Sample locations DW-31-320, DW-36-205, USGS-58-260, USGS-51-250, USGS-60-355, USGS-44-295, and USGS-18 were designated as field duplicate samples.

-- = Not Applicable

Page 1 of 1

001774

Analyte (1) UnitsLocation of Maximum

Concentration

Detection Frequency

Range of Reporting

Limits2-Butanone 5.0 11.1 µg/L DW-30-210 56 / 60 5.0 - 5.0

Acetone 10.5 31.8 µg/L DW-30-425 58 / 60 5.0 - 5.0Barium 35.3 40.6 µg/L USGS-50 2 / 2 --

Bromodichloromethane 38.2 40 µg/L DW-36-205 1 / 60 0.5 - 0.5Bromoform 28.3 30.9 µg/L DW-36-205 1 / 60 0.5 - 0.5

Calcium 90,000 93,800 µg/L USGS-18 2 / 2 --Chloroform 0.5 63 µg/L DW-36-205 5 / 60 0.5 - 0.5

cis-1,2-Dichloroethene 0.6 10.9 µg/L DW-30-305 23 / 60 0.5 - 0.5Dibromochloromethane 40.8 43.9 µg/L DW-36-205 1 / 60 0.5 - 0.5

Iron 55.5 55.5 µg/L USGS-50 1 / 2 25.0 - 25.0Magnesium 14,300 16,000 µg/L USGS-18 2 / 2 --

Methyl tert-butyl ether 0.50 1.1 µg/L USGS-58-210 8 / 60 0.5 - 0.5Potassium 1,520 1,640 µg/L USGS-50 2 / 2 --Sodium 9,960 11,000 µg/L USGS-50 2 / 2 --

Tetrachloroethene 3.7 78.7 µg/L DW-30-305 28 / 60 0.5 - 0.5Toluene 1.2 1,220 µg/L DW-31-170 9 / 60 0.5 - 0.5

Trichloroethene 0.50 12.3 µg/L DW-30-305 25 / 60 0.5 - 0.5

Notes:µg/L - Micrograms per liter(1) Sample DECON-2 was not included in the data summary because it is not a ground water sample.

TABLE 4 JANUARY 2008 GROUND WATER SAMPLING DATA SUMMARY

(DETECTED ANALYTES)


(Qualifier)


(Qualifier)

Page 1 of 1

001775

Sample Location (1) Passive Diffusion Bag Placement(Feet Below Top of Casing) Date Time


Analysis

USGS-60 (2) 200; 250; 355; 370; 378; 388 4/14/2008 0752 X

USGS-51 (2) 125; 200; 250; 290; 370; 385 4/14/2008 0936 X

USGS-58 (2, 3) 120; 210; 260; 290; 340; 375 4/14/2008 1332 X

DW-43 (2, 3) 90; 160; 180; 210; 255 4/14/2008 1420 X

USGS-42 (4) 90; 100; 115; 135; 150; 165 4/15/2008 1145 XUSGS-20 108; 128; 139 4/15/2008 1407 X

USGS-44 (2, 3) 240; 295; 320; 390; 425; 455 4/16/2008 0826 X

Notes:

(4) A blind duplicate sample (named DW-401) was collected from USGS-42-135.

TABLE 5 APRIL 2008 PASSIVE DIFFUSION BAG PRIVATE WELL SAMPLING

(1) Passive diffusion bags were redeployed for future sampling as necessary.(2) Sample locations DW-43-180, USGS-44-320, USGS-51-370, USGS-58-260, and USGS-60-355 were designated as laboratory quality assurance/quality control samples.(3) Sample locations DW-43-255, USGS-44-295, and USGS-58-340 were designated as field duplicate samples.

Page 1 of 1001776

Sample Location Date Time

Volatile Organic

Compound Analysis


Compound Analysis

Inorganic Analysis 1,4-Dioxane

Natural Attenuation Parameters

Methane, Ethane, and

Ethene

USGS-27 4/14/2008 0945 X -- X -- -- --DW-117 4/14/2008 1106 X -- X -- -- --DW-36 4/14/2008 1138 X X X X X --DW-21 4/14/2008 1217 X -- X -- -- --DW-37 4/14/2008 1545 X X X X X --

USGS-21 4/14/2008 1800 X -- X -- -- --DW-30 4/14/2008 1915 X X X X X XDW-31 4/15/2008 0852 X X X X X --

USGS-18 4/15/2008 0932 X X X X -- --DW-44 4/15/2008 0940 X X X X X X

USGS-50 4/15/2008 1036 X X X X -- --DW-400 4/15/2008 1046 X -- X -- -- --DW-39 4/15/2008 1252 X X X X X --DW-40 4/15/2008 1352 X -- X -- -- --DW-10 4/15/2008 1453 X -- X -- -- --

USGS-10 4/15/2008 1628 X -- X -- -- --DW-47 4/15/2008 1735 X X X X X XDW-48 4/16/2008 0855 X -- X -- -- --

DW-108 4/16/2008 0940 X -- X -- -- --DW-33 4/16/2008 1040 X -- X -- -- --DW-19 4/16/2008 1047 X -- X -- -- --DW-18 4/16/2008 1150 X -- X -- -- --DW-16 4/16/2008 1327 X -- X -- -- --DW-60 4/16/2008 1408 X -- X -- -- --DW-11 4/16/2008 1458 X -- X -- -- --

Notes:

TABLE 6APRIL 2008 PRIVATE AND MUNICIPAL WELL WATER SAMPLING INFORMATION

(1) Natural attenuation parameters included: nitrite, nitrate, sulfate, sulfide, chloride, total organic carbon, ammonia, and ortho-(2) All samples were collected from residential wells at or close to the pump as described in the field notes except for USGS-18 and USGS-50, which were collected from the City of Leon Valley municipal wells.(3) Bold/Italics samples were designated as laboratory quality assurance/quality (4) Underline sample locations were designated as field duplicate samples.-- = Not applicable

Page 1 of 1

001777

Analyte UnitsLocation of Maximum

Concentration

Detection Frequency

Range of Reporting

Limits1,1-Dichloroethene 0.5 2 µg/L USGS-42-90 8 / 64 0.5 - 0.5

2-Butanone 5.1 J 5.7 J µg/L USGS-20-108 2 / 64 5.0 - 5.0Acetone 5 J 21 J µg/L USGS-60-250 13 / 64 5.0 - 5.0Barium 32 192 µg/L DW-48 25 / 25 -Benzene 2.5 2.9 µg/L DW-401 7 / 64 0.5 - 0.5

Benzoic acid 9.6 J 9.6 J µg/L DW-30D 1 / 9 10.0 - 9.9Calcium 79,600 143,000 µg/L DW-37 25 / 25 -

Chloroform 0.8 1.2 µg/L USGS-42-90 8 / 64 0.5 - 0.5Chloromethane 0.60 0.70 µg/L USGS-58-340 3 / 64 0.5 - 0.5

cis-1,2-Dichloroethene 1 1,640 µg/L USGS-42-90 14 / 64 0.5 - 0.5Copper 25.5 25.5 µg/L DW-33 1 / 25 20.0 - 20.0

Iron 25.7 11,300 µg/L DW-48 14 / 25 25.0 - 25.0Lead 3.8 7 µg/L DW-48 3 / 25 2.0 - 2.0

Magnesium 3,780 23,100 µg/L USGS-27 25 / 25 -Manganese 7.6 108 µg/L DW-48 4 / 25 5.0 - 5.0

Methyl tert-butyl ether 1.3 17.1 µg/L USGS-42-100 12 / 64 0.5 - 0.5Potassium 1,230 6,060 µg/L USGS-27 25 / 25 -Sodium 8,960 83,500 µg/L DW-37 25 / 25 -

Tetrachloroethene 3 7,700 µg/L USGS-42-165 17 / 64 0.5 - 0.5Toluene 1.3 1.3 µg/L USGS-60-200 2 / 64 0.5 - 0.5

trans-1,2-Dichloroethene 7.7 9.9 µg/L DW-401 7 / 64 0.5 - 0.5Trichloroethene 0.6 1,120 µg/L USGS-42-165 14 / 64 0.5 - 0.5

Trichlorofluoromethane 0.50 0.60 µg/L DW-39 1 / 64 0.5 - 0.5Vinyl chloride 1.0 1.1 µg/L USGS-42-165 7 / 64 0.5 - 0.5

Zinc 25.7 1,060 µg/L DW-37 16 / 25 20.0 - 20.0

Notes:µg/L - Microgram(s) per liter

TABLE 7APRIL 2008 GROUND WATER SAMPLING DATA SUMMARY

(DETECTED ANALYTES)


(Qualifier)


(Qualifier)

Page 1 of 1

001778

Sample Location (1) Passive Diffusion Bag Placement(Feet Below Top of Casing) Date Time Volatile Organic

Compound Analysis

USGS-60 (2, 4) *200; 250; 355; *370; 378; 388 7/14/2008 0748 X

USGS-58 ( 3) 120;*210; 260; 290; 340; *375 7/14/2008 0830 XUSGS-51 125; *200; 250; 290; 370; *385 7/14/2008 0915 X

DW-43 (2) 90; 160; *180; 210; 255 7/14/2008 1015 XUSGS-44 *240; 295; 320; 390; *425; 455 7/14/2008 1225 XUSGS-42 *90; *100; *115; *135; *150; *165 7/15/2008 0819 XUSGS-20 108; *128; *139 7/15/2008 1302; 1335 X

Notes:

Bold/* denote sample collection depths.

TABLE 8 JULY 2008 PASSIVE DIFFUSION BAG PRIVATE WELL SAMPLING INFORMATION

(1) Passive diffusion bags were redeployed for future sampling as necessary.(2) Sample locations USGS-60-370, and DW-43-180 were designated as laboratory quality assurance/quality control samples.(3) Sample location USGS-58-375 was designated as a field duplicate sample.(4) Passive diffusion bags were not redeployed because the private well is scheduled for plugging and abandonment.

Page 1 of 1

001779



Analysis

Inorganic Analysis

Natural Attenuation Parameters

USGS-42 7/15/2008 0912 X X X

Notes:

TABLE 9JULY 2008 HYDRASLEEVETM SAMPLING INFORMATION

Monitored natural attenuation parameters included: nitrite, nitrate, sulfate, sulfide, chloride, total organic carbon, ammonia, and ortho-phosphate.Bold/Italics samples were designated as laboratory quality assurance/quality control samples.Underline sample locations were designated as field duplicate samples.HydraSleeveTM deployment and sample collection depth was 145 feet below ground surface.

Page 1 of 1

001780


Volatile Organic

Compound Analysis

Inorganic Analysis

USGS-18 7/15/2008 1410 X XUSGS-50 7/15/2008 1435 X XDW-42 7/15/2008 1317 X X

Notes:

TABLE 10PRIVATE AND MUNICIPAL WELL WATER SAMPLING

Private well sample DW-42 was collected close to the pump. Samples USGS-18 and USGS-50 were collected from the City of Leon Valley municipal wells.Bold/Italics samples were designated as laboratory quality assurance/quality control samples.Underline sample locations were designated as field duplicate samples.

Page 1 of 1

001781

Analyte UnitsLocation of Maximum

Concentration

Detection Frequency

Range of Reporting

Limits1,1-Dichloroethene 2.2 J 7.4 µg/L USGS-42-90 7 / 21 0.5 - 0.5

Ammonia as N 0.05 U 0.050 U µg/L USGS-42D 1 / 1 -Barium 36 156 µg/L USGS-42 4 / 4 -Benzene 2.2 3.0 µg/L USGS-42 7 / 21 0.5 - 0.5Calcium 91,900 174,000 µg/L USGS-42 4 / 4 -Chloride 37 37 µg/L USGS-42 1 / 1 -

Chloroform 0.9 J 2.8 µg/L USGS-42-90 7 / 21 0.5 - 0.5cis-1,2-Dichloroethene 2.3 2,130 µg/L USGS-42-90 8 / 21 0.5 - 0.5

Copper 20.5 20.5 µg/L USGS-18 1 / 4 20.0 - 20.0Dichlorodifluoromethane 0.50 0.50 µg/L DW-42 1 / 21 0.5 - 0.5

Iron 165 281 µg/L DW-42 2 / 4 25.0 - 25.0Magnesium 9,050 18,000 µg/L DW-42 4 / 4 -Manganese 19 36.7 µg/L USGS-42 2 / 4 5.0 - 5.0

Methyl tert-butyl ether 1.4 28.3 µg/L USGS-42-90 9 / 21 0.5 - 0.5Nitrate as N 2.5 3 µg/L USGS-42 1 / 1 -

Nitrate+Nitrite as N 2.71 2.74 µg/L USGS-42 1 / 1 -Nitrite as N 0.20 0.21 µg/L USGS-42D 1 / 1 -

Orthophosphate as P, Lab Filt 0.02 U 0.03 µg/L USGS-42D 1 / 1 -Potassium 1,500 3,600 µg/L USGS-42 4 / 4 -

Sodium 10,000 36,100 µg/L USGS-42 4 / 4 -Sulfate 46 46 µg/L USGS-42 1 / 1 -Sulfide 0.010 0.010 µg/L USGS-42 1 / 1 -

Tetrachloroethene 1.4 11,700 µg/L USGS-42-90 9 / 21 0.5 - 0.5Toluene 0.80 0.80 µg/L USGS-60-200 1 / 21 0.5 - 0.5

Total Organic Carbon, NPOC 2.0 10 µg/L USGS-42 1 / 1 -trans-1,2-Dichloroethene 7.8 J 15.2 µg/L USGS-42-90 7 / 21 0.5 - 0.5

Trichloroethene 2.5 1,510 µg/L USGS-42-90 8 / 21 0.5 - 0.5Vinyl chloride 1.3 J 2.9 µg/L USGS-42-90 7 / 21 0.5 - 0.5

Zinc 434 435 µg/L DW-42 1 / 4 20.0 - 20.0

Notes:µg/L - Microgram(s) per liter

TABLE 11 JULY 2008 GROUND WATER SAMPLING DATA SUMMARY

(DETECTED ANALYTES)


(Qualifier)


(Qualifier)

Page 1 of 1001782

Sample Location Date Time Volatile Organic Compound Analysis

USGS-18 9/9/2008 0930 XUSGS-50 9/9/2008 1030 XUSGS-18 10/9/2008 0915 XUSGS-50 10/9/2008 1005 X

Notes:

TABLE 12MUNICIPAL WELL WATER SAMPLING INFORMATION

Samples USGS-18 and USGS-50 were collected from the City of Leon Valley municipal wells.Bold/Italics samples were designated as laboratory quality assurance/quality control samples.Underline sample locations were designated as field duplicate samples.-- = Not applicable

Page 1 of 1

001783

Analyte PDB

Concentration at USGS-42-135

Units Sample Date

Sample Time Units Sample

DateSample Time

HydraSleeve Concentration at

145 feetUnits Sample Date Sample

Time

Benzene 2.3 µg/L 7/15/2008 0819 2.2 µg/L 7/15/2008 0819 3 µg/L 7/15/2008 0912Choloroform 0.9 µg/L 7/15/2008 0819 0.9 µg/L 7/15/2008 0819 1.1 µg/L 7/15/2008 0912

cis-1,2-Dichloroethene 1,120 µg/L 7/15/2008 0819 1,150 µg/L 7/15/2008 0819 1,530 µg/L 7/15/2008 0912Methyl tert-butyl ether 24.7 µg/L 7/15/2008 0819 25 µg/L 7/15/2008 0819 27.6 µg/L 7/15/2008 0912

Tetrachloroethene 5,240 µg/L 7/15/2008 0819 5,450 µg/L 7/15/2008 0819 6,670 µg/L 7/15/2008 0912Trans-1,2-dichloroethene 9 µg/L 7/15/2008 0819 7.8 µg/L 7/15/2008 0819 10.9 µg/L 7/15/2008 0912

Trichloroethene 854 µg/L 7/15/2008 0819 862 µg/L 7/15/2008 0819 1,210 µg/L 7/15/2008 0912Vinyl chloride 1.3 µg/L 7/15/2008 0819 1.3 µg/L 7/15/2008 0819 2.3 µg/L 7/15/2008 0912

Notes:

PDB Concentrations at USGS-42-150

TABLE 13PASSIVE DIFFUSION BAG AND HYDRASLEEVETM

ANALYTE CONCENTRATION COMPARISON AT USGS-42

µg/L - Microgram(s) per liter

Page 1 of 1

001784



ATTACHMENT A

DATA VALIDATION REPORT SUMMARIES

001785

UNITED STATES ENVIRONMENTAL PROTECTION AGENCYRegion 6 Laboratory

10625 Fallstone Road, Houston, TX 77099Phone: (281)983-2100 Fax: (281)983-2248

Sample Collection Date(s)--

Site Name ---------------------Bandera Road Groundwater Plume

Contact------------------------- Chris Villarreal (6SF-RA)

Report Date-------------------- 12/26/07

Environmental Services Branch

Project #----------------------- 08SF044

Final Analytical Report

11/12/07- 11/13/07

07110140711016

Work Order(s)-----------------

Analyses included in this report:ABN CLP Routine List Metals ICP 200.7Metals ICP-MS 200.8 VOA CLP Low Level (0.5)

Report Narrative

Semi-volatile analysis:

Two RPDs outside QC limits on the MS/MSD. No target were reported in the source sample.

Volatile analysis:

Acetone and 2-Butanone, where reported, are qualified as estimated due to the failure of thisanalyte on alternate source check.

Some analytes are qualified as blank related in samples 0711016-01 and 0711016-09 due to thepresence of the qualified analyte in the associated field blank.

Sample 0711016-08 was analyzed twice due to failed surrogate recoveries. Chloromethane and Carbon tetrachloride are qualified as estimated due to difference in concentrations found betweenthe two vials analyzed.

ICP Metals:

Batch B7K2109:

BS1: Calcium is high in this control; the results are qualified and may be biased high. The lab 001786

Report Narrative (cont'd)control results for sodium and potassium are below the reporting level and can not be reliablycalculated.

BS2/MS2/MS4: The high level of silver in these controls is not expected to be recovered by thisprep method.

MS1/MS2/MS3/MS4: Calcium, magnesium, potassium, and sodium concentrations exceed the spike added concentrations by a factor of four or more and recoveries can not be reliablycalculated.

Batch B7K2602:

BLK1: Copper was found in the prep blank above the reporting level; the results are qualified but should not be affected.

BS1: Calcium is high in this control sample; the results are qualified and may be biased high. The lab control results for potassium and sodium are below the reporting level and can not bereliably calculated.

BS2/MS3/MS4: The high level of silver in these controls are not expected to be recovered by this prep method.

MS1/MS2/MS3/MS4: Calcium, magnesium, potassium, sodium, and zinc concentrations exceedthe spike added concentrations by a factor of four or more and can not be reliably calculated.

Reporting limits are adjusted for sample size and matrix interference.

Standard procedures for quality assurance and quality control were followed in the analysis andreporting of the sample results. The results apply only to the samples tested. This final reportshould only be reproduced in full.

Richard McMillinRegion 6 Laboratory Branch ChiefDavid Neleigh

Report Approvals:

Region 6 Laboratory Manager001787

Comments:

Received by and Date__________________________________________________/_____/_______

Christy WarrenData Management CoordinatorRegion 6 Laboratory6MD-HS

Please sign and date this form below and return it with any comments to:

Please have the U.S. EPA Project Manager/Officer call the Data Management Coordinator at 3-2137 for any comments or questions.

Date Transmitted: _____/_____/_______

/ /Data Management Coordinator: Christy Warren

Houston, Texas 77099

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

Region 6 Environmental Services Branch Laboratory10625 Fallstone Road

Data Management Coordinator Signature Date

The laboratory routinely disposes of samples 90 days after all analyses have been completed. If you have a need to hold these samples in custody longer than 90 days, please sign below.

____________________________________________ ___________________Signature Date

Please provide a reason for holding:

Sample Receipt and Disposal

Project Number: 08SF044Site Name: Bandera Road Groundwater Plume

001788






Report Date-------------------- 03/05/08


Project #----------------------- 08SF087


01/28/08- 01/29/08

08010240801026

Work Order(s)-----------------

Analyses included in this report:ABN CLP Routine List Metals ICP 200.7Metals ICP-MS 200.8 VOA CLP Low Level (0.5)

Report Narrative

Volatile Analysis:

Sample 0801024-07 is designated as PDB-trip blank and contains Acetone and 2-Butanone (PDB stands for passive diffusion bag). All samples collected with passive diffusion bag and containAcetone and 2-Butanone have these results qualified as blank related due to the presence of theseanalytes in the PDB-trip blank. This excludes field QC and 3 field samples.

In sample 0801024-25 Toluene is qualified as estimated due to the failure of this analyte in thematrix spikes B8B0501-MS3/MSD3.

Sample 0801026-01 has Acetone qualified as blank related due to the presence of this analyte inthe associated preparation blank.

All Acetone and 2-Butanone results are qualified as estimated in work order 0801026 due to failure of these analytes on the alternate source check for the calibration curve.

The reporting limits for Methyl acetate and 1,2-Dibromo-3-chloropropane are 1.0 ug/l in work order 0801024 due to the inability to analyze for this analyte at 0.5 ug/l on the instrument used for analysis.

Metals ICP:

001789

Report Narrative (cont'd)Batch B8B0401:

BS1/MS1: The lab control results for sodium and potassium are below the reporting level andcan not be reliably calculated.

BS2/MS2: The high level of silver in these controls are not expected to be recovered by this prepmethod.

MS1/MSD1/MS2/MSD2: Sodium, magnesium, and calcium concentrations exceed the spikeadded concentration by a factor of four or more and can not be reliably calculated.




Report Approvals:


Comments:












____________________________________________ ___________________Signature Date




001791






Report Date-------------------- 05/19/08


Project #----------------------- 08SF134


04/14/08- 04/16/08

0804020080402108040220804023

Work Order(s)-----------------

Analyses included in this report:ABN 8270 Dioxane ABN CLP Routine ListMetals ICP 200.7 Metals ICP-MS 200.8VOA CLP Low Level (0.5)

Report Narrative

Sample Management:

This report contains the VOA, ABN, Dioxane, and Total Metals data only. The ammonia,nitrate, nitrite, chloride, sulfate, o-Phosphate, sulfide, and TOC are parameters that are analyzed for by the TCEQ. The TCEQ data will be reported as soon as it is available.

Semi-volatile Analysis:

Benzoic acid is qualified as estimated in sample 0804020-04 due to problems with chromatography on calibration.

Volatile Analysis:

One analyte fails slightly low in BS1. This analyte was not found in the associated samples.

Acetone was found above the reporting limit at 5.2 ug/l in both vials used for MS and MSD for sample 0804023-18. It was not found above the reporting limit in the vial used to report thesample results. Acetone and 2-Butanone, where reported, are qualified as estimated due to second sourceverification failure.

001792

Report Narrative (cont'd)

ICP Metals:

Batch B8D2302:

BS1:The control results for potassium and sodium are below the reporting limits and can not bereliably calculated.

BS2/MS3/MS4: The high level of silver in these controls are not expected to be recovered by thisprep method.

MS1/MS2/MS3/MS4/MS5/MS6: Calcium, sodium, potassium, and magnesium concentrations exceed the spike added concentrations by a factor of four or more and can not be reliablycalculated.

ICP-MS Metals: Acceptable QC.




Report Approvals:


Comments:












____________________________________________ ___________________Signature Date




001794

TestAmericaTHE LEADER IN ENVIRONMENTAL TESTING

1/19

Certificate of Analysis

Austin· 14050Summit Drive, SuiteA100,Austin, TX 78728 • Tel 512 2440855 • Fax 512 2440160· www.testamericainc.com

ANALYTICAL REPORT

Bandera Road Groundwater Plm.

Lot #: I8D160253

Doug McReynolds

EA Engineering, Science and Te405 South Highway 121

Building CSuite 100

Lewisville, TX 75067

TESTl\..MERIc..~ I:.-n...BOP~~TORIES, TIJC.

Neal J. SalcherProject Manager

April 25, 2008

American Council ofIndependent LaboratoriesInternational Association ofEnvironmental Testing Laboratories

TAL-4122-260 (1007)

001795

Case Narrative

LOT NUMBER: 18D160253

This report contains the analytical results for the four-samples received under chain of custodyby TestAmerica Laboratories, Inc. on April 16,2008. These samples are associated with yourBandera Road Groundwater Plm. project.

All samples were received in good condition and within temperature requirements.

All applicable quality control procedures met method-specified acceptance criteria except wherenoted in the case narrative or flagged on the result pages.

This report shall not be reproduced except in full, without the written approval of the laboratory.

If you have any questions, please feel free to call me at (512) 310-5215.

2/19

001796

EXECUTIVE SUMMARY - Detection Highlights

18D160253

REPORTING ANALYTICALPARAMETER RESULT LIMIT UNITS METHOD

DW-47 04/15/08 17:35 001

Methane 6.1 0.50 ug/L RSK SOP-175

DW-44 04/15/08 09:40 003

Methane 0.77 0.50 ug/L RSK SOP-175

3/19

001797

ANALYTICAL METHODS SUMMARY

I8D160253

4/19

PARAMETER

Dissolved Gases in Water

References:

ANALYTICALMETHOD

RSK SOP-175

RSK Sample Prep and Calculations for Dissolved Gas Analysisin Water Samples Using a GC Headspace EquilibrationTechnique, RSKSOP-175, REV. 0, 8/11/94, USEPA Research Lab

001798

SAMPLE SUMMARY

I8D160253

5/19

WO # SAMPLE# CLIENT SAMPLE ID

KLEREKLERNKLERPKLERV

NOTE (8)

001002003004

DW-47DW-30DW-44TRIP BLANK

SAMPLED SAMPDATE TIME

04/15/08 17 :3504/14/08 19:1504/15/08 09:4004/15/08 20:00

- The analytical results of the samples listed above are presented on the following pages.

- All calculations are performed before rounding to avoid round-off errors in calculated results.

- Results noted as "ND" were not detected at or above the stated limit.

- This report must not be reproduced, except in full, without the written approval of the laboratory.

- Results for the following parameters are never reported on a dry weight basis: color, corrosivity, density, flashpoint, ignitability, layers, odor,

paint filter test, pH, porosity pressure, reactivity, redox potential, specific gravity, spot tests, solids, solubility, temperature, viscosity, and weight.

001799






Report Date-------------------- 06/17/08


Project #----------------------- 08SF134


04/14/08- 04/15/08

0804020080402108040220804023

Work Order(s)-----------------

Analyses included in this report:Ammonia 350.1 Chloride 300.0Nitrate - 353.2 Nitrate + Nitrite 353.2Nitrite - 353.2 o-Phospate 365.1Sulfate 300.0 (#) Sulfide 376.2Total Organic Carbon 415.2

Report Narrative

Sample Management:

This report contains the ammonia, nitrate, nitrite, chloride, sulfate, o-phosphate, sulfide, and TOCdata. The VOA, ABN, Dioxane, and total metals data were previously reported.




Report Approvals:


Comments:












____________________________________________ ___________________Signature Date




001801






Report Date-------------------- 08/19/08


Project #----------------------- 08SF200


- 7/15/20087/14/2008

08070130807019

Work Order(s)-----------------

Analyses included in this report:Metals ICP 200.7 Metals ICP-MS 200.8VOA CLP Low Level (0.5)

Report Narrative

Sample Management:

This report contains the VOA and metals data only. The ammonia, chloride, nitrate, nitrite, sulfate, sulfide, TOC, and o-Phosphate are analyses performed by the TCEQ Houston Laboratory. The TCEQ data will be reported as soon as it is available.

VOA:

Toluene is qualified as blank related in sample 0807013-16 due to the presence of this analyte in the associated trip/field blanks. Acetone is qualified as blank related in sample 0807019-03 due to the presence of this analyte in the associated analysis blank.

Samples 0807019-11, 0807019-12 and 0807019-13:

All three samples had two surrogates outside QC limits on original analysis (not reported). Initial reanalyses were performed at dilutions only. The samples were reanalyzed again using an openvial on 7/23/08 in order to meet requested RLs. Because the vial was open, all results on 7/23/08 are qualified as estimated. Additionally, the surrogate 1,2-Dichloroethane-d4 fails high for these samples on 7/23/08. Tetrachloroethene is qualified as estimated in sample 0807019-11 due to inconsistent concentrations found among vials analyzed.

The surrogate Toluene-d8 fails low in sample 0807019-14.001802

Report Narrative (cont'd)

All BSs have failing analytes. Of the BSs that have failing analytes, only one BS4 had analytes that were found in the associated samples. None of the failing analytes were reported from thatday of analysis.

1,1-Dichloroethene fails high in MSD2. Two RPDs fail on MS2/MSD2. No targets werereported in the source sample.

ICP Metals:

Batch B8G1711:

BS2/MS2: The high level of silver in this control is not expected to be recovered by this prepmethod.

BS1: The lab control results for sodium and potassium are below the reporting level and can notbe reliably calculated.

MS1/MS2: Calcium, magnesium, and sodium concentrations exceed the spike addedconcentrations by a factor of four or more and can not be reliably calculated.




Report Approvals:


Comments:












____________________________________________ ___________________Signature Date




001804






Report Date-------------------- 09/30/08


Project #----------------------- 08SF200


7/15/2008

08070130807019

Work Order(s)-----------------

Analyses included in this report:Ammonia 350.1 Chloride 300.0 (#)Nitrate - 353.2 Nitrate + Nitrite 353.2Nitrite - 353.2 o-Phospate 365.1Sulfate 300.0 Sulfide 376.2Total Organic Carbon 415.2

Report Narrative

Sample Management:

This report contains the ammonia, chloride, nitrate, nitrite, sulfate, sulfide, TOC, ando-Phosphate data only. The VOA and metals data were previously reported.

TOC:

Samples 0807019-08 and 0807019-15 were analyzed after the holding time was exceeded.




Report Approvals:


Comments:












____________________________________________ ___________________Signature Date




001806

Environmental Protection Agency

Region 6 Laboratory10625 Fallstone Road, Houston, TX 77099

Phone:(281)983-2100 Fax:(281)983-2248

Station ID Laboratory ID Sample Type Date Collected

ANALYTICAL REPORT FOR SAMPLES

Date Received

0807019-08 Liquid 07/16/08 08:55USGS-42 7/15/08 9:12

0807019-15 Liquid 07/16/08 08:55USGS-42D 7/15/08 9:12

Page 1 of 9Report Name: 0807013,0807019 FINAL 09 30 08 1326

001807






Report Date-------------------- 10/14/08


Project #----------------------- 08SF252


9/9/2008

0809011Work Order(s)-----------------

Analyses included in this report:VOA CLP Low Level (0.5)

Report Narrative

Sample Management:

Samples were received at 16° C.

VOA:

Acetone is qualified as blank related in sample 0809011-01 due to presence of this analyte in the associated analysis blank.

Bromomethane is qualified as estimated in the BS because the concentration reported is slightlyabove the calibration range.




Report Approvals:


Comments:












____________________________________________ ___________________Signature Date




001809


Region 6 Laboratory



Site Name --------------------- Bandera Road Groundwater Plume


Report Date-------------------- 10/30/08


Project #----------------------- 09SF015


10/9/2008 9:15:00AM

0810021Work Order(s)-----------------

Analyses included in this report:

VOA CLP Low Level (0.5)

Report Narrative

Acetone is qualified as estimated in sample 0810021-01 due to the failure of this analyte on the

second source verification for the calibration curve.


Standard procedures for quality assurance and quality control were followed in the analysis and

reporting of the sample results. The results apply only to the samples tested. This final report

should only be reproduced in full.


Report Approvals:

Region 6 Laboratory Manager

001810

Comments:

Received by and Date

__________________________________________________/_____/_______

Christy Warren

Data Management Coordinator

Region 6 Laboratory

6MD-HS


Please have the U.S. EPA Project Manager/Officer call the Data Management Coordinator at 3-2137 for any

comments or questions.


/ /

Data Management Coordinator: Christy Warren



Region 6 Environmental Services Branch Laboratory

10625 Fallstone Road


The laboratory routinely disposes of samples 90 days after all analyses have been completed. If you have a need

to hold these samples in custody longer than 90 days, please sign below.

____________________________________________ ___________________

Signature Date




001811



ATTACHMENT B

EON PRODUCTS INFORMATIONAL MATERIAL

001812

P.O. Box 443, Sne l l v i l le , Georg ia 30078

800-474-2490 770-978-9971 Fax : 770 -978-8661 www.eonpro.com

Dear Diffusion Sampler User: On rare occasion we have a customer who mentions that acetone has appeared in the analytical results from a sample taken using a deionized water filled, polyethylene based passive diffusion bag sampler (PDBs). Users of PDBs should be aware that PDBs are not to be used for analysis of acetone and several other volatile compounds, and that the presence of these compounds in analytical results does not necessarily mean the compounds are in the groundwater. Acetone, MEK and several related VOCs exhibit very poor diffusion in water across the polyethylene membrane which makes the Polyethylene PDBs unsuitable for measuring these compounds. Because of the low diffusion rate, trace amounts of these compounds that may occur in the deionized fill water will not diffuse or will diffuse very slowly through the membrane. Therefore if these compounds were present in the water from the beginning it is possible they will show up when the lab work is done. Acetone is commonly used in laboratories and therefore is a fairly common contaminant in trace amounts in deionized water. The contaminant may enter the water by direct contact in the lab through liquid or equipment or airborne acetone may diffuse into the water through air/water contact. There is also some speculation that airborne acetone may permeate a filled polyethylene membrane more readily that water borne acetone. Because of the possibility of acetone contamination in the water used to fill the samplers we always advise that the user take water "blanks" and / or equipment rinsate "blanks" prior to the deployment of the PDB into the well so that the fill water can be tested to show what the water contained prior to installation. We suggest A fill-water blank should also be sent to the lab on the same day that the sample is recovered in case there was acetone in the air when the sampler-water was transferred to VOA vials or in the air in the lab when they were analyzed. Based on our observations we strongly suspect that for cases of acetone “hits” either the fill water had acetone in it or there was acetone in the air when the samples were transferred or analyzed. As part of our quality assurance program we have had the Equilibrator Passive Diffusion Samplers tested by an independent lab using rinsate blanks to demonstrate that the EON PDBs are not a source of acetone. The results came back negative for the presence of these compounds. We are certain that the PDBs are not introducing the acetone into the analysis. The absence of acetone in these tests is consistent with the absence of acetone in the manufacture of the materials and in the storage and handling of the samplers. Acetone has a lower boiling point than the materials used to construct the samplers which means that even trace amounts that could have come in contact with the raw materials would have vaporized during the manufacturing process. The materials used are all “virgin”, having no previous use or contact with suspect chemicals. Please contact us if you have additional questions or comments. Sincerely,

Bradley Varhol

001813

P.O. Box 390246, Sne l l v i l le , Georg ia 30039 800-474-2490 770-978-9971 Fax : 770 -978-8661

www.eonpro.com

Pre-filled Diffusion Samplers Thank you for your order for pre-filled Equilibrator™ Passive Diffusion Samplers. We appreciate the opportunity to provide the world’s leading passive diffusion samplers (PDBs) along with our services. The enclosed Equilibrator™ samplers have been filled at our facility with Reagent Grade ASTM Type I Water obtained from NERL Diagnostic laboratories and which has been tested and certified by NERL at the time it was prepared. The water meets or exceeds C.A.P., A.C.S., USP/NF and N.C.C.L.S. for Purified and Reagent Grade. NERL Diagnostics performs an analysis on each Lot of water they produce and they list the results of the analysis on their website at www.nerl.com/. This product complies with and exceeds the requirements for lab grade “de-ionized” water recommended in the ITRC Guidance document. A copy of the lot certification will be provided on request. Please check the samplers to be sure they are intact after shipping and immediately report to us if there are any problems. For Quality Assurance we strongly recommend that you remove the plug from at least one sampler per water lot and fill a VOA to create a field-water blank to be tested at your lab. The plug may be reinserted into the sampler and the sampler used for sampling. Lab testing of the field-water blank will provide information about the chemistry of the water at the time the samplers are deployed and the results may be helpful in the event unexpected compounds are indicated on the lab report. Please remember that PDBs are not for use in sampling acetone, MEK, Butanone, and certain other compounds and that the potential presence of these compounds in a lab report does not indicate the presence in a well. Acetone and related compounds are almost universally used at labs and are a common lab contaminant at trace amounts in deionized water, typically around 20ppb or less. Presence of these compounds can also be an artifact from the testing lab. The fill water for these samplers was selected to exceed the sampling requirements at an affordable price. We will be pleased to provide fill water which meets user supplied specifications on request. Sincerely,

Bradley Varhol President

001814

P.O. Box 390246, Sne l l v i l le , Georg ia 30039 800-474-2490 770-978-9971 Fax : 770 -978-8661

www.eonpro.com

February 12, 2008 Dear Passive Diffusion User: We do NOT use Acetone in any part of the construction or preparation of the Equilibrator™ samplers, nor is Acetone used in the manufacture of the polyethylene bag, polyethylene mesh, polyethylene nozzle & plug, or the stainless steel clamp. The fact that you are getting Acetone hits in your sample means that the Acetone is coming from either the interior of the sampler, which could only be the fill water, or from contact with acetone during the discharge or vial filling process or in the lab during analysis. Acetone does not diffuse through the membrane and so, if there is Acetone in the fill water it will stay in the sampler until emptied for analysis, and conversely, if there is Acetone in the groundwater it will not enter the sampler. While I am not saying that the lab is the source, consider that Acetone is a commonly used lab solvent and occasionally found in trace amounts in lab prepared deionized water. We have encountered hits of Acetone in ASTM Type I & II water purchased from lab vendors for samplers that we have pre-filled for other customers. Our standard recommendation to clients for both unfilled and pre-filled samplers is to obtain fill-water blanks so that the presence of Acetone and other non diffusive compounds can be determined in advance and "backed-out" of the post sampling analysis. I have a suggestion for you for a quick way to verify whether there is or is not acetone in the well. Install a couple HydraSleeves and sample the intervals of concern. Be sure to install the HydraSleeves and then let them sit for awhile before sampling so the well can re-stratify if needed. I hope this information helps. Please let me know whatever we can do to be helpful. Best regards, Bradley Varhol EON Products, Inc.

001815

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