Draft_2016-2017LUC_and_LTM_Report_Site_DP005,_AVGAS_Sludge_Burial_Site_A.pdf

DRAFT

2016 - 2017 LAND USE CONTROL AND

LONG TERM MANAGEMENT REPORT

Site DP005, AVGAS Sludge Burial Site A

Dobbins Air Reserve Base Marietta, Georgia

JANUARY 2017

Prepared for:

AIR FORCE CIVIL ENGINEER CENTER

JOINT BASE SAN ANTONIO

Lackland, Texas

Prepared by:

PROFESSIONAL ENVIRONMENTAL ENGINEERS, INC.

9393 West 110th Street Overland Park, KS 66170 816-556-3290

DRAFT

2016 - 2017 LAND USE CONTROL AND LONG-TERM MANAGEMENT REPORT:

SITE DP005, AVGAS SLUDGE BURIAL SITE A

January 2017

Prepared for:

Air Force Civil Engineer Center

REVIEW AND APPROVAL

Project Manager: _________________________________________ _______________ Robert J. Louden Date Professional Environmental Engineers, Inc.

2016 - 2017 LAND USE CONTROL AND LONG TERM MANAGEMENT LUC/LTM REPORT

DOBBINS AIR RESERVE BASE TABLE OF CONTENTS

JANUARY 2017 DRAFT

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TABLE OF CONTENTS

Section Page No.

1.0 INTRODUCTION

1.1 OBJECTIVE

1.2 ORGANIZATION OF LUC/LTM REPORT

2.0 BACKGROUND

2.1 SITE DESCRIPTION

2.2 PREVIOUS ACTIVITIES

2.3 REGULATORY OVERVIEW

3.0 2016 – 2017 LUC/LTM ACTIVITIES

3.1 APPROVED DEVIATIONS FROM THE WORK PLAN

3.2 WELL ABANDONMENT

3.3 MONITORING WELL AND LUC INSPECTIONS

3.4 GROUNDWATER LEVEL MEASUREMENTS

3.5 SAMPLE COLLECTION

3.6 LABORATORY ANALYSES AND QUALITY ASSURANCE/QUALITY CONTROL

3.7 DATA VALIDATION

3.8 INVESTIGATION-DERIVED WASTE

4.0 GROUNDWATER ANALYTICAL RESULTS

5.0 CONCLUSIONS AND RECOMMENDATIONS

6.0 REFERENCES

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LIST OF TABLES

Table 1 Site DP005 Well Inspection Summary Table 2 Site DP005 Groundwater Level Measurements Table 3 Site DP005 Detection Limits and Limits of Quantitation Applicable to Current

Sample Results Table 4 Site DP005 Groundwater Analytical Results Table 5 Site DP005 Groundwater Monitoring Well GPS Locations

LIST OF FIGURES

Figure 1 Site Location Map Figure 2 Groundwater Monitoring Well Locations Figure 3a Potentiometric Surface Map – March 2016 Figure 3b Potentiometric Surface Map – October 2016 Figure 4a Groundwater Quality Map – March 2016 Figure 4b Groundwater Quality Map – October 2016

APPENDICES

Appendix A Site Photographs Appendix B Field Forms and Logbook Appendix C Data Quality Evaluation Report Appendix D Laboratory Analytical Data Sheets Appendix E Georgia Environmental Protection Division Monitoring Only Report Appendix F Site Ranking Form

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LIST OF ABBREVIATIONS AND ACRONYMS

% percent µg/L micrograms per liter AFCEC Air Force Civil Engineer Center amsl above mean sea level ARB Air Reserve Base AST aboveground storage tank AVGAS aviation gas BTEX benzene, toluene, ethylbenzene, and xylenes BTOC below top of casing COC contaminant of concern DL detection limit DoD U.S. Department of Defense DVE dual-phase vacuum extraction EDD electronic data deliverable ELAP Environmental Laboratory Accreditation Program EPA U.S. Environmental Protection Agency EPD Environmental Protection Division ERP Environmental Restoration Program ft feet GA Georgia GPS Global Positioning System ID identification IDW investigation-derived waste ISWQS Georgia In-Stream Water Quality Standard LCS laboratory control sample LCSD laboratory control sample duplicate LOQ limit of quantitation LTM Long Term Management LUC Land Use Control MCL maximum contaminant level mg/L milligrams per liter MOR Monitor Only Report MS matrix spike MSD matrix spike duplicate MTBE methyl tert-butyl ether

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NA not applicable or not available NFA no further action PARCC precision, accuracy, representativeness, completeness, and comparability PE Professional Environmental Engineers, Inc.

PQO project quality objective PVC polyvinyl chloride QA quality assurance QC quality control RIs remedial investigations RPD relative percent difference SVOC semi-volatile organic compound TestAmerica TestAmerica, Inc.

Tetra Tech Tetra Tech EM, Inc.

TO Task Order UFP-QAPP Unified Federal Policy – Quality Assurance Project Plan UST underground storage tank VOC volatile organic compound

2016-2017 LAND USE CONTROL AND LONG TERM MANAGEMENT LUC/LTM REPORT

DOBBINS AIR RESERVE BASE 1.0 – INTRODUCTION

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1.0 INTRODUCTION

Professional Environmental Engineers, Inc. (PE), was retained by the Air Force Civil Engineer Center (AFCEC), under Contract No. GS10F200BA, Delivery Order FA8903-16-R-0006, to conduct specified work at Dobbins Air Reserve Base (ARB), in Marietta, Georgia, as part of the Land Use Control (LUC) and Long Term Management (LTM) activities for Site DP005, AVGAS (aviation gas) Sludge Burial Site A. The specified work included project management and planning, preparation and submittal of revised work plans, monitoring well and LUC inspections, groundwater monitoring and sampling, analytical testing, investigation-derived waste (IDW) disposal, data evaluation, and preparation of an LUC/LTM report.

This LUC/LTM Report includes a summary of the groundwater sampling activities and an evaluation of the groundwater data collected from 25 October 2016 to 27 October 2016. The work was performed in accordance with the site-specific Final Work Plan prepared by PE under this Delivery Order and the existing Facility-Wide Unified Federal Policy – Quality Assurance Project Plan (UFP-QAPP) prepared by others under contract FA8903-09-D-8582 Task Order (TO) 0003 (2014). A Project Management Plan and Health and Safety Plan were also prepared by PE for work under this contract.

1.1 OBJECTIVE

The objective of the annual sampling event described in this LUC/LTM report was to collect groundwater data for the Air Force to monitor contaminant of concern (COC) concentration trends in groundwater over time. Groundwater data is collected annually by the Air Force to evaluate the effectiveness of the former remedy, and confirm that the LUCs at Site DP005 remain protective of human health and the environment.

1.2 ORGANIZATION OF LUC/LTM REPORT

The LUC/LTM Report is organized as follows:

• Section 1.0 - Introduction, provides a brief introduction to the project, the objective, and contents of this document.

• Section 2.0 - Background, provides a site description, an abbreviated chronology of historical use and previous activities conducted at the site, and the present regulatory status of Site DP005.

• Section 3.0 - Groundwater Sampling and Well Abandonment Activities, discusses well abandonment, groundwater sampling event tasks, deviations from the Final Work Plan, laboratory analyses and quality assurance (QA)/quality control (QC), data validation/usability and overall assessment, and IDW management.

• Section 4.0 - Groundwater Analytical Results, discusses the analytical results for the samples collected during the groundwater monitoring/sampling event.

2016-2017 LAND USE CONTROL AND LONG TERM MANAGEMENT LUC/LTM REPORT

DOBBINS AIR RESERVE BASE 1.0 – INTRODUCTION

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• Section 5.0 - Conclusions and Recommendations, presents the conclusions and recommendations for Site DP005.

• Section 6.0 - References, provides list of references cited in text.

Figures and tables are presented at the end of the report text. In addition, this LUC/LTM Report includes the following appendices:

• Appendix A - Photographs, presents photographs of site features, groundwater monitoring wells and groundwater sampling activities.

• Appendix B - Field Forms and Logbook, provides the completed field forms and logbook entries used to document field activities.

• Appendix C - Data Quality Evaluation Report, provides an assessment of the overall quality of the data.

• Appendix D - Laboratory Analytical Data Sheets, provides the complete analytical data package for this work.

• Appendix E - Georgia (GA) Environmental Protection Division (EPD) Monitor Only Report (MOR), provides a completed MOR report (required form by GA EPD).

• Appendix F - Site Ranking Form, provides a ranking of the site based on contamination levels (required form by GA EPD).

DOBBINS AIR RESERVE BASE 2.0 – BACKGROUND

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2.0 BACKGROUND

The following subsections provide the site description, an abbreviated chronology of historical use and previous activities conducted at the site, and the present regulatory status of Site DP005.

2.1 SITE DESCRIPTION

Site DP005 is situated in the northern part of Dobbins ARB (see Figure 1) and is co-located with one of the base’s fuel storage areas. The fuel storage area (near the central portion of DP005) includes a chain-link perimeter fence with two gated entry points; two large above-ground jet fuel storage tanks and fueling equipment are present on the interior of this storage area. An administration building is located just outside the southern fenced boundary of the fuel storage area and is bordered to the south by Atlantic Avenue SE, which forms the southern boundary of DP005. Wooded areas and a creek are present along the DP005 site’s northern and eastern boundaries, and a paved access road is present on the western boundary that allows large aircraft to reach nearby Air Force Plant 6. Refer to Figure 2 – Groundwater Monitoring Well Locations, for additional site characteristics.

Six former (removed) 25,000-gallon fuel underground storage tanks (USTs) and existed on the eastern portion of the fuel storage area (from the 1940’s to 1991), and the two existing aboveground storage tanks (ASTs) are still in daily use. Until approximately 1973, it was common practice to dispose of fuel sludge in unlined burial pits during tank cleanouts. During at least one of these cleanouts, tank sludge was disposed of in a pit in the general proximity of the six former USTs and Site DP005 (AFCEC, 2014); the burial pit is shown on Figure 2 as possibly existing near the north boundary of the existing fuel storage area. A number of monitoring wells exist on the site, including those used to investigate/monitor groundwater at DP005 and those used to for other purposes on the Dobbins ARB.

2.2 PREVIOUS ACTIVITIES

An abbreviated chronology of historical use and previous activities at Site DP005 is summarized below.

• 1940’s to 1973: The site was used as a storage and handling facility for aviation fuels and waste disposal of sludge residues from cleaning tanks.

• August 1991: Six USTs were removed from the site; closure samples were collected during UST removal activities.

• September 1996: A comprehensive analytical report was prepared, which included environmental site data collected through 1996. The analytical report included data on soil, groundwater, and surface water samples collected as part of a Phase II confirmation and quantification study conducted in 1986, remedial investigations (RIs) conducted in 1988 and 1993, and other Environmental Restoration Program (ERP) investigations conducted in 1995 and 1996.

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• April 2004: A dual-phase vacuum extraction (DVE) system with five remediation wells began operation at Site DP005; oversight and enforcement of the cleanup activities occurred through the Georgia EPD UST Program. Quarterly groundwater monitoring was implemented from 2004 to 2006; semi-annual groundwater monitoring was implemented from 2006 to 2008.

• March 2009: The Georgia EPD approved deactivation of the DVE system. The system was shut down following groundwater monitoring in December 2008. Post-shutdown semiannual groundwater monitoring was implemented through December 2010.

• October 2009: The DVE system was decontaminated and removed from active service;

however, the equipment was left in place.

• March 2011: The Georgia EPD UST program approved No Further Action (NFA) for Site DP005 and requested a completion report and certification documenting that the associated monitoring wells and remediation equipment were properly abandoned.

However, Dobbins ARB elected to retain the remediation equipment and associated wells in order to evaluate the remedy effectiveness and to determine if any additional activities were warranted.

• March 2012: Inspection and maintenance of the DVE system was conducted.

Maintenance activities include operating the blower, cleaning and lubricating the equipment, removing accumulated rainwater, and spraying the blower with a rust inhibitor.

• July 2012: Maintenance activities at seven monitoring wells were performed, which included rust removal and painting, repair of metal covers and casings, and replacement of broken external well parts. The exterior of the protective steel bollards and the well covers were painted safety yellow. LUCs and applicable restrictions were also inspected to verify change in land use, land disturbances, or indication of drilling activity over the previous year.

• February 2015: Inspection and groundwater sampling of six monitoring wells was performed, groundwater levels were measured, and liquid IDW was transferred to the Dobbins ARB hazardous waste storage site and then shipped to an off-site licensed facility.

• March 2015: PE was awarded Delivery Order FA8903-15-F-0011 (under existing Contract # GS10F200BA) to perform LUC/LTM activities at Site DP005 for a 1-year period.

• March 2016: Inspection and groundwater sampling of seven monitoring wells was performed, groundwater levels were measured, and liquid IDW was transferred to the Dobbins ARB hazardous waste storage site and then shipped to an off-site licensed facility.

One well was abandoned.

• March 2016: PE was awarded Delivery Order FA8903-16-R-0010 (under existing Contract # GS10F200BA) to perform LUC/LTM activities at Site DP005 for a 1-year period.

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Figure 2 shows the site features including the location of groundwater monitoring wells, the DVE system, the suspected AVGAS sludge burial pit, the existing ASTs, and the approximate location of the six former 25,000 gallon fuel USTS. A detailed summary of the site, historical investigations and analytical results, and remedial activities conducted at Site DP005 are presented in the Final Remediation System Report [Tetra Tech EM, Inc. (Tetra Tech), 2011] and 2014 Five Year Review Report (HDR, 2014).

2.3 REGULATORY OVERVIEW

In December 2010, the requirements for NFA under the Georgia UST Program regulations were attained (Georgia EPD, 2011). Based on recommendations in a 2014 Five Year Review Report for the entire base (HDR, 2014); however, LUCs are being implemented at Site DP005, supplemented by long-term groundwater monitoring. The groundwater data is collected annually to evaluate the effectiveness of the remedy and to assure that LUCs at Site DP005 remain protective of human health and the environment.

DOBBINS AIR RESERVE BASE 3.0 – 2016 – 2017 LUC/LTM ACTIVITIES

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3.0 2016 – 2017 LUC/LTM ACTIVITIES

The following sections describe the tasks that were implemented for the 2016 - 2017 LUC/LTM event, including recording static water level measurements and Global Positioning System (GPS) locations for on-site monitoring wells, monitoring well and LUC inspections, well abandonment, groundwater purging and sample collection, laboratory analyses and QA/QC, data validation and assessment of data usability, and IDW management. The following sections also summarize deviations from the Final Work Plan.

3.1 APPROVED DEVIATIONS FROM THE WORK PLAN

PE was contracted to perform the current work that includes sampling eleven on-site wells (D5- W11R, D5-W35, D5-W36, D5-W51, D5-W52, D5-W53, D5-W54, D5-W55 D5-W57, D5-W58, and ITS-7,) and abandoning one well (D5-W47R). However, PE personnel were not able to locate some of the specified wells while performing work at the project site. Monitoring wells D5-W47R, D5-W52. D5-W53, D5-W54, and D5-W55 could not be located and are presumed to have previously been abandoned. However, PE personnel located and identified one additional monitoring well D5-W56 (previously thought to be abandoned), while performing the current work. The well was sampled as a replacement for D5-W54 due to its proximity to the presumably abandoned well; it is flush-mounted with 4-inch polyvinyl chloride (PVC) well casing and is located inside the fenced fueling area near the northern boundary. Figure 2 shows the location of this and the other monitoring wells that are known to exist at the project site.

It should be noted that PE used existing maps, GPS coordinates (where available), and a magnetometer in an effort to locate these missing wells. Additionally, PE used shovels to dig into the subsurface in areas where the wells were supposed to be located. Although there was no written record of the previous well abandonments, PE often found pieces of grout material within the areas where these wells were supposed to be located, suggesting that they had already been abandoned.

3.2 WELL ABANDONMENT

As noted above, monitoring well D5-W47R was scheduled for abandonment as part of the current work. PE personnel were not able to locate the well and presume that it was previously abandoned.

3.3 MONITORING WELL AND LUC INSPECTIONS

As part of the original scope of work, PE noted the condition of all wells on the DP005 site (including wells that were not sampled under this contract) and well features, such as concrete pads, protective casings, the presence of caps and locks, etc. A summary of the well inspections is provided in Table 1.

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The perimeter fencing and two gated entries present at Site DP005 are in good condition and the gates operate properly. Informational signage is present at both gated entry points including “Warning – Controlled Area,” “No Unauthorized Vehicles,” “Danger – No Open Flames Or Ignition Sources Beyond This Point,” and a National Fire Protection Association (NFPA) Fire Diamond placard. The eastern entry gate also has a sign present that indicates “No Civilian Vehicles Beyond This Point.”

The two large jet fuel ASTs present at the site include secondary containments that are in good condition and appear to be appropriately sized. It should be noted that the western storage tank was not in service at the time of performing the present groundwater sampling work. This was due to internal sandblasting and recoating activities being performed on the tank (refer to photographs included in Appendix A for additional site details).

3.4 GROUNDWATER LEVEL MEASUREMENTS

PE personnel recorded static groundwater level measurements on 25 October 2016. Additional groundwater level measurements were recorded on 26 and 27 October 2016 (see Appendix B).

Groundwater level measurements were made using an electronic water level indicator, and recorded as depth to water from the top of the PVC well casing. The depth to water was then subtracted from the surveyed elevation of the top of casing to determine the groundwater elevation in each well. The groundwater level measurements and groundwater elevations, including the identification of each well gauged and sampled, are provided in Table 2.

Groundwater elevations were used to prepare a potentiometric surface map, which is provided as Figure 3b. Groundwater elevations and contours from the previous (March 2016) sampling event are provided in Figure 3a for comparison purposes. Both sampling events indicate a groundwater flow direction to the east/northeast (toward creek) at a gradient between 0.014 (October 2016) and 0.024 (March 2016) feet per feet. In general, groundwater elevations were four to six feet higher in March 2016 than they were in October 2016.

3.5 SAMPLE COLLECTION

Groundwater samples were collected from eight monitoring wells during performance of the current work. Groundwater samples were collected using low-flow sampling methods via a bladder pump. The eight monitoring wells sampled included: D5W-11R, D5W-35, D5W-36, D5W- 51, D5-W56, D5W-57, D5W-58, and ITS-7. Water quality/stabilization parameters were monitored during purging using a multi-parameter water-quality instrument capable of monitoring temperature, specific conductivity, dissolved oxygen, pH, and oxidation-reduction potential. A turbidity meter was utilized to collect turbidity measurements. The field forms, including the Well Purging/Field Water Quality Measurements Forms, are provided in Appendix B.

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3.6 LABORATORY ANALYSES AND QUALITY ASSURANCE/QUALITY CONTROL

Groundwater samples were analyzed by TestAmerica, Inc. (TestAmerica), of Savannah, Georgia.

The analytes were selected based on the historical COCs and to assess continued remedy protectiveness for the cleanup of Site DP005. The groundwater samples were analyzed for volatile organic compounds (VOCs), including benzene, toluene, ethylbenzene, total xylenes (BTEX) and methyl tert-butyl ether (MTBE), in accordance with U.S. Environmental Protection Agency (EPA) Method 8260B. Groundwater samples were also analyzed for semi-volatile organic compounds (SVOCs) in accordance with EPA Method 8270D. Analytical results were reported to their respective detection limits (DLs). The default laboratory DLs and limits of quantitation (LOQs) for these laboratory results are presented in Table 3.

The laboratory QC program utilized by TestAmerica included analyses of laboratory replicates, method blanks, surrogate spikes, internal standards, laboratory control samples (LCS), matrix spikes (MS), and matrix spike duplicates (MSD). To allow the analytical laboratory to run MS/MSD analyses, additional samples were collected in the field to provide sufficient volume. A total of one MS/MSD sample pair was analyzed and complied with the QAPP-specified frequency rate requirement of an MS/MSD pair for every 20 field samples collected.

No field duplicate sample were collected as part of the field QC program. In addition, trip blanks (provided by the laboratory) were submitted as part of the field QC program. Trip blanks were added to the shipping cooler with groundwater samples for VOCs collected each day. A total of three trip blanks were analyzed and are associated with samples collected on 25 October 2016 through 27 October 2016. No target analytes were detected in the trip blanks.

3.7 DATA VALIDATION

PE conducted data validation in accordance with the Final Site-Specific Work Plan and Facility- Wide UFP-QAPP, applicable methodologies, and laboratory established accuracy and precision control limits. Appendix C contains the data validation report for this project. DL and LOQ values were checked, and the data is considered usable and acceptable.

3.8 INVESTIGATION-DERIVED WASTE

Liquid IDW generated during monitoring and sampling activities included decontamination fluids and purge water from monitoring wells. Approximately 25 gallons of liquid IDW were generated while performing this work. The liquid IDW was transported to the Dobbins ARB hazardous waste storage site (for disposal at on-site treatment facility) on 27 October 2016, pending receipt of the laboratory analytical results to determine disposition of the liquid IDW. The analytical results were electronically transmitted to Mr. William Powell, Base Hazardous Waste Manager, on 14 November 2016.

DOBBINS AIR RESERVE BASE 4.0 – GROUNDWATER ANALYTICAL RESULTS

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4.0 GROUNDWATER ANALYTICAL RESULTS

Groundwater analytical data were evaluated against EPA Maximum Contaminant Levels (MCLs), (EPA, 2015) and Georgia In-Stream Water Quality Standards (ISWQS) (Georgia Department of Natural Resources, 2012). The analytical results are summarized below; analytical results for the sampling event are also presented in Table 4 and shown on Figure 4b (results from the previous sampling events are shown on Figure 4a for comparison purposes). The complete laboratory analytical packages are provided in Appendix D.

• Groundwater collected from monitoring well D5-W11R showed detectable concentrations of volatile constituent including isopropylbenzene (6.6 micrograms per liter (µg/L)), methylcyclohexane (3.9 µg/L), and methyl tert-butyl ether (1.5 µg/L, estimated)). None of the constituent concentrations exceed EPA MCLs or EPD ISWQSs.

• Groundwater collected from monitoring well D5-W35 did not show any detectable concentrations of constituents included in the volatile and semi-volatile analytical methods. Based on these results, no constituent concentrations exceed EPA MCLs or EPD ISWQSs.

• Groundwater collected from monitoring well D5-W36 showed detectable concentrations of volatile constituents including benzene (5.3 µg/L), isopropylbenzene (20 µg/L), methylcyclohexane (99 µg/L) and total xylenes (180 µg/L). Analytical results also reported detectable concentrations of semi-volatile constituents including 1-1’-biphenyl (1.2 µg/L, estimated), 2-methylnaphthalene (6.3 µg/L, estimated), and naphthalene (10 µg/L). The benzene concentration in groundwater exceeded the EPA MCL, but was below the EPD

ISWQS.

• Groundwater collected from monitoring well D5-W51 showed detectable concentrations of volatile constituents including benzene (13 µg/L), ethylbenzene (8.8 µg/L), isopropylbenzene (5.1 µg/L) and methylcyclohexane (1.4 µg/L). Analytical results also reported detectable concentrations of semi-volatile constituents including acenaphthene (0.94 µg/L, estimated), carbazole (3.7 µg/L, estimated), dibenzofuran (1.1 µg/L, estimated), 2,4-dimethylphenol (6.5 µg/L, estimated), fluoranthene (1.5 µg/L, estimated), naphthalene (10 µg/L), and phenol (1.7 µg/L, estimated). The benzene concentration in groundwater exceeded the EPA MCL, but was below the EPD ISWQS.

• Groundwater collected from monitoring well D5-W56 showed detectable concentrations of only semi-volatile constituents including carbazole (1.7 µg/L, estimated), fluoranthene (1.2 µg/L, estimated), and pyrene (0.83 µg/L, estimated). None of these constituent concentrations exceed EPA MCLs or EPD ISWQSs.

• Groundwater collected from monitoring well D5-W57 showed detectable concentrations of volatile constituents including benzene (980 µg/L), chlorobenzene (1.4 µg/L, DOBBINS AIR RESERVE BASE 4.0 – GROUNDWATER ANALYTICAL RESULTS

Page 10 Providing professional, cost-effective solutions estimated), ethylbenzene (310 µg/L), isopropylbenzene (18 µg/L), methylcyclohexane (47 µg/L), toluene (13 µg/L), and total xylenes (950 µg/L). Analytical results also reported semi-volatile constituent concentrations above detection limits including acenaphthene (1.3 µg/L, estimated), 1-1’-biphenyl (1.8 µg/L, estimated), carbazole (2.2 µg/L, estimated), dibenzofuran (0.79 µg/L, estimated), 2,4-dimethylphenol (42 µg/L), fluoranthene (0.75 µg/L, estimated), fluorene (1.1 µg/L, estimated), 2-methylnaphthalene (7.9 µg/L, estimated), 2-methylphenol (100 µg/L), phenanthrene (1.7 µg/L, estimated), phenol (2.0 µg/L, estimated), and pyrene (0.67 µg/L, estimated). Benzene concentrations for well D5- W57 exceeded both the EPA MCL and the GA EPD ISWQS for this constituent.

• Groundwater collected from monitoring well D5-W58 showed detectable concentrations of volatile constituents including benzene (2.4 µg/L), ethylbenzene (0.53 µg/L, estimated), isopropylbenzene (3.9 µg/L), and total xylenes (4.7 µg/L). Analytical results also reported detectable concentrations of semi-volatile constituents including acenaphthene (1.7 µg/L, estimated), anthracene (0.77 µg/L, estimated), benzo(a)anthracene (1.5 µg/L, estimated), 1-1’-biphenyl (0.64 µg/L, estimated), carbazole (2.8 µg/L, estimated), chrysene (0.75 µg/L, estimated), and dibenzofuran (1.2 µg/L, estimated). None of the constituent concentrations exceed EPA MCLs or EPD ISWQSs.

• Groundwater collected from monitoring well ITS-7 did not show detectable concentrations of volatile or semi-volatile constituents. Based on these results, no constituent concentrations exceed EPA MCLs or EPD ISWQSs.

DOBBINS AIR RESERVE BASE 5.0 – CONCLUSIONS AND RECOMMENDATIONS

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5.0 CONCLUSIONS AND RECOMMENDATIONS

As part of the LUC/LTM activities performed by the Air Force, groundwater samples were collected in accordance with directives from AFCEC from groundwater monitoring wells D5- W11R, D5-W35, D5-W36, D5-W51, D5-W56, D5-W57, D5-W58, and ITS-7. Groundwater samples were analyzed for volatile organic compounds and semi-volatile organic compounds.

Groundwater analytical data was evaluated against EPA MCLs and Georgia ISWQS. Benzene was the only COC with concentrations in groundwater higher than either the EPA MCL or the Georgia ISWQS. Groundwater from monitoring wells D5-W36, D5-W51 and D5-W57 had benzene concentrations that exceeded the EPA MCL of 5 µg/L. Only groundwater from monitoring well D5-W57 contained a benzene concentration higher than both the EPA MCL and the ISWQS of

71.28 µg/L. None of the other wells had concentrations of COCs exceeding the MCL or the ISWQS for benzene.

A GA EPD UST MOR and Site Ranking Form (required submittals) are included as Appendices E and F, respectively. PE recommends that the site continue to be monitored on an annual basis until groundwater concentrations are below the EPA MCL and GA ISWQS.

DOBBINS AIR RESERVE BASE 6.0 – REFERENCES

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6.0 REFERENCES

Air Force Civil Engineer Center, 2015. Performance Work Statement for Land Use Control and Long Term Management at Dobbins ARB, Contract # GS10F200BA, Delivery Order

FA8903-15-F-0011.

Georgia Department of Natural Resources, 2012. Georgia In-Stream Water Quality Standards.

Georgia Environmental Protection Division, 2011. Letter from William E. Logan, Advanced Geologist, Corrective Action Unit II, Georgia Underground Storage Tank Management Program, to Hal Huddleston, USAF 94th MSG/CC, Dobbins ARB, 28 March.

HDR, 2014. Second Five-Year Review, Revision 1, 94th Airlift Wing, Dobbins Air Reserve Base, Marietta, Georgia, January.

Sullivan-Weston Services JVA, LLC, 2013. Facility-Wide Unified Federal Policy – Quality Assurance Project Plan for Performance-Based Remediation, Air Force Plant 6 and Dobbins Air Reserve Base, Marietta, Georgia, June.

Sullivan-Weston Services JVA, LLC, 2015. Final Long Term Monitoring Report: Perform Land Use Control and Long Term Monitoring for Site DP005 AVGAS Sludge Burial Site, Dobbins Air Reserve Base, Marietta, Georgia, May.

Tetra Tech EM, Inc., 2011. Final Remediation System Report No. 17. August 2010 to December 2010, AVGAS Sludge Burial Site A (DP-05), 531 Atlantic Avenue, Dobbins Air Reserve Base, Marietta, Georgia, March.

United States Environmental Protection Agency, 2016. Maximum Contaminant Levels, May.

TABLES

Table 1 – Site DP005 Well Inspection Summary Dobbins Air Reserve Base

Marietta, Georgia

Well Labeled?

Condition of Well Label

Locked?

Flush

Mount or Stickup

Well Cap Type and

Status

Condition of

Protective Casing

Condition of

Concrete Pad

Measuring Point

Marked?

Comment

D5-W11R Yes Good Yes Stickup PVC good

Intact Intact Yes 2” well outside fenced area

D5-35 Yes Good Yes Stickup PVC good

Intact Intact Yes 2” well outside fenced area

D5-36 Yes Good Yes Stickup PVC good

Intact Intact Yes 2” well outside fenced area

D5-W51 No N/A Yes Stickup PVC good

Intact Intact Yes 4” well in fenced area

D5-W56 NO N/A No* Flush Mount

PVC

good

Intact Intact Yes 4” well in fenced area

D5-W57 No N/A No* Flush mount

PVC

good

Intact Intact No 2” well in fenced area

D5-W58 No N/A No* Flush mount

PVC

good

Intact Intact No 2” well in fenced area

ITS-7 Yes Good Yes Stickup PVC good

Intact Intact Yes 2” well outside fenced area

B10587 Yes Good Yes Stickup ---- Intact Intact ----- 2” well outside fenced area

B10MWL Yes Good Yes Stickup ---- Intact Intact ----- 2” well outside fenced area

B10MWM Yes Good Yes Stickup ---- Intact Intact ----- 4” well outside fenced area

ITS 8 Yes Good Yes Stickup ---- Intact Intact ----- 2” well outside fenced area

B10B11 Yes Good Yes Stickup ---- Intact Intact Yes 4” well outside fenced area

Notes:

* Flush mount wells are secured with bolt-on covers that are intact and functional unless otherwise noted.

Table 2 – Site DP005 Groundwater Level Measurements Dobbins Air Reserve Base

Marietta, Georgia

Well Date Top of Casing Elevation (ft amsl)

Depth to Groundwater

Groundwater Elevation (ft amsl)

D5-W11R 10/25/2016 1065.54 (W11) 18.99 1046.55

D5-35 10/25/2016 NA 20.86 NA

D5-36 10/25/2016 1061.92 16.53 1045.39 D5-W51 10/25/2016 1074.74 24.91 1049.83

D5-W56 10/25/2016 NA 19.66 NA

D5-W57 10/25/2016 1072.07 21.66 1050.41 D5-W58 10/25/2016 1071.57 21.65 1049.92

ITS-7 10/25/2016 NA 19.62 NA

ft amsl feet above mean sea level NA not available

Table 3 – Site DP005 Detection Limits and Limits of Quantitation Applicable to Current Sample Results Dobbins Air Reserve Base

Marietta, Georgia

Analyte Limit Of Quantitation Detection Limit Unit Volatile Organic Compounds Benzene 2 0..86 µg/L Chlorobenzene 2 0.52 µg/L 1,4-Dichlorobenzene 2 0.92 µg/L Ethylbenzene 2 0.66 µg/L 2-Hexanone 20 4.0 µg/L Isopropylbenzene 2 0.70 µg/L Methylcyclohexane 2 0.86 µg/L Methyl tert-butyl ether 20 0.60 µg/L Toluene 2 0.96 µg/L Total Xylenes 2 0.23 µg/L Semivolatile Organic Compounds Acenaphthene 9.5 0.72 µg/L Acenaphthylene 9.5 0.81 µg/L Acetophenone 9.5 0.54 µg/L Anthrcene 9.5 0.66 µg/L Benzo (a) anthracene 9.5 0.52 µg/L 1-1'-Biphenyl 9.5 0.55 µg/L Carbazole 9.5 0.68 µg/L Chrysene 9.5 0.49 µg/L 2-Chloronaphthalene 9.5 0.76 µg/L Dibenzofuran 9.5 0.75 µg/L 2,4-Dimethylphenol 9.5 1.0 µg/L Fluoranthene 9.5 0.70 µg/L Fluorene 9.5 0.91 µg/L 2-Methylnaphthalene 9.5 0.74 µg/L 2-Methylphenol 9.5 0.85 µg/L Naphthalene 9.5 0.67 µg/L Phenanthrene 9.5 0.73 µg/L Phenol 9.5 0.79 µg/L Pyrene 9.5 0.60 µg/L

Only analytes with concentrations reported above detection limit are shown on this table.

µg/L micrograms per liter mg/L milligrams per liter NA Not Analyzed

Table 4 – Site DP005 Groundwater Analytical Results Dobbins Air Reserve Base

Marietta, Georgia

Screening Levels Georgia

ISWQS

EPA

MCL D5-W11R D5-W35

Date December

March

October

December

March

October

Volatile Organic Compounds Benzene 71.28 5 0.054 U 1 U 1.0 U 0.054 U 1 U 1.0 U Chlorobenzene 21,000 100 NA 0.5 U 0.50 U NA 0.5 U 0.50 U 1,4-Dichlorobenzene 2,600 75 NA 1 U 1.0 U NA 1 U 1.0 U Ethylbenzene 28,718 700 NA 1 U 0.50 U NA 1 U 0.50 U 2-Hexanone NA NA NA 5 U 5.0 U NA 5 U 5.0 U Isopropylbenzene NA NA NA 2.9 6.6 NA 0.5 U 1.0 U Methylcyclohexane NA NA NA 1 U 3.9 NA 1 U 1.0 U Methyl tert-butyl ether NA NA NA 0.5 U 1.5 J NA 0.5 U 0.50 U Toluene 200,000 1,000 NA 1 U 1.0 U NA 1 U 1.0 U Total Xylenes NA 10,000 NA 0.5 U 0.50 U NA 0.5 U 0.50 U Semivolatile Organic Compounds Acenaphthene 990 NA NA 1.9 U 1.9 U NA 2 UJ 2.0 U Acenaphthylene NA NA NA 1.9 U 1.9 U NA 2 UJ 2.0 U Acetophenone NA NA NA 1.9 U 1.9 U NA 2 U 2.0 U Benzo (a) anthracene 0.0311 NA NA 0.95 U 1.9 U NA 0.99 U 2.0 U 1-1'-Biphenyl NA NA NA 1.9 U 1.9 U NA 2 UJ 2.0 U Carbazole NA NA NA 1.9 U 1.9 U NA 2 U 2.0 U 2-Chloronaphthalene NA NA NA 1.9 U 1.9 U NA 2 UJ 2.0 U Dibenzofuran NA NA NA 1.9 U 1.9 U NA 2 UJ 2.0 U 2,4-Dimethylphenol NA NA NA 9.5 U 9.6 U NA 9.9 U 2.0 U Fluoranthene 370 NA NA 1.9 U 1.9 U NA 2 U 2.0 U Fluorene 14,000 NA NA 1.9 U 1.9 U NA 2 U 2.0 U 2-Methylnaphthalene NA NA NA 1.9 U 1.0 J NA 2 UJ 2.0 U 2-Methylphenol NA NA NA 1.9 U 1.9 U NA 2 U 2.0 U Naphthalene NA NA NA 1.9 U 2.8 J NA 2 UJ 2.0 U Phenanthrene NA NA NA 1.9 U 1.9 U NA 2 U 2.0 U Phenol 300 NA NA 1.9 U 1.9 U NA 2 U 2.0 U Pyrene 11,000 NA NA 1.9 U 1.9 U NA 2 U 2.0 U Total Petroleum Hydrocarbons

TPH-DRO NA NA NA 650 NA NA 82 J NA

TPH-ORO NA NA NA 190 U NA NA 100 U NA

TPH-GRO NA NA NA 81 MH NA NA 25 UH NA

Monitored Natural Attenuation Parameters Ethane NA NA NA 7.9 NA NA 4.7 NA Ethylene NA NA NA 7.7 NA NA 4.6 NA Methane NA NA NA 1,300 NA NA 4.9 NA Nitrate-N 10,000 10,000 NA 58 M NA NA 190 M NA Nitrite-N NA 1,000 NA 46 U NA NA 46 U NA Sulfate NA NA NA 610 JM NA NA 1,200 NA Sulfide NA NA NA 1,000 U NA NA 1,100 NA Total Organic Carbon NA NA NA 1,900 NA NA 980 J NA Alkalinity NA NA NA 52,000 B NA NA 14,000 B NA

Table 4 – Site DP005 Groundwater Analytical Results (continued) Dobbins Air Reserve Base

Marietta, Georgia

Screening Levels Georgia

ISWQS

EPA

MCL D5-W36 D5-W47R

Date December

February

March

October

December

Volatile Organic Compounds Benzene 71.28 5 15.2 10 F 8.6 D 5.3 D 917 Chlorobenzene 21,000 100 NA NA 1 U 1.0 U NA 1,4-Dichlorobenzene 2,600 75 NA NA 2 U 2.0 U NA Ethylbenzene 28,718 700 NA 5.8 F 7.7 D 1.0 U NA 2-Hexanone NA NA NA NA 10 U 10 U NA Isopropylbenzene NA NA NA NA 44 D 20 D NA Methylcyclohexane NA NA NA NA 190 D 99 D NA Methyl tert-butyl ether NA NA NA NA 1 U 1.0 U NA Toluene 200,000 1,000 NA 4.4 U 2 U 2.0 U NA Total Xylenes NA 10,000 NA 620 540 180 NA Semivolatile Organic Compounds Acenaphthene 990 NA NA NA 2 U 1.9 U NA Acenaphthylene NA NA NA NA 2 U 1.9 U NA Acetophenone NA NA NA NA 15 1.9 U NA Benzo (a) anthracene 0.0311 NA NA NA 1 U 1.9 U NA 1-1'-Biphenyl NA NA NA NA 2.1 J 1.2 J NA Carbazole NA NA NA NA 2 U 1.9 U NA 2-Chloronaphthalene NA NA NA NA 2 U 1.9 U NA Dibenzofuran NA NA NA NA 2 U 1.9 U NA 2,4-Dimethylphenol NA NA NA NA 10 U 9.5 U NA Fluoranthene 370 NA NA NA 2 U 1.9 U NA Fluorene 14,000 NA NA NA 2 U 1.9 U NA 2-Methylnaphthalene NA NA NA NA 20 6.3 J NA 2-Methylphenol NA NA NA NA 2 U 1.9 U NA Naphthalene NA NA NA NA 28 10 NA Phenanthrene NA NA NA NA 2 U 1.9 U NA Phenol 300 NA NA NA 2 U 1.9 U NA Pyrene 11,000 NA NA NA 2 U 1.9 U NA Total Petroleum Hydrocarbons

TPH-DRO NA NA NA NA 2,000 NA NA

TPH-ORO NA NA NA NA 190 UQ NA NA

TPH-GRO NA NA NA NA 3,900 MHQ NA NA

Monitored Natural Attenuation Parameters Ethane NA NA NA 1.8 1.1 UM NA NA Ethylene NA NA NA 3.8 1 U NA NA Methane NA NA NA 2,500 3.8 M NA NA Nitrate-N 10,000 10,000 NA 35 U 46 U NA NA Nitrite-N NA 1,000 NA NA 46 U NA NA Sulfate NA NA NA 250 F 800 UM NA NA Sulfide NA NA NA 3,000 UM 1,000 U NA NA Total Organic Carbon NA NA NA 2500 1900 NA NA Alkalinity NA NA NA 75,000 46,000 B NA NA

Dobbins Air Reserve Base

Marietta, Georgia

Screening Levels Georgia

ISWQS

EPA

MCL D5-W51

Date December

February

March

October

Volatile Organic Compounds Benzene 71.28 5 3.62 4.5 1.1 13 Chlorobenzene 21,000 100 NA NA 0.5 U 0.50 U 1,4-Dichlorobenzene 2,600 75 NA NA 1 U 1.0 U Ethylbenzene 28,718 700 NA 9.2 2.1 8.8 2-Hexanone NA NA NA NA 3.3 J 5.0 U Isopropylbenzene NA NA NA NA 2.3 5.1 Methylcyclohexane NA NA NA NA 1 U 1.4 Methyl tert-butyl ether NA NA NA NA 0.5 U 0.50 U Toluene 200,000 1,000 NA 0.22 F 1 U 1.0 U Total Xylenes NA 10,000 NA 0.43 U 0.5 U 0.50 U Semivolatile Organic Compounds Acenaphthene 990 NA NA NA 2 U 0.94 J Acenaphthylene NA NA NA NA 2 U 1.9 U Acetophenone NA NA NA NA 2 U 1.9 U Benzo (a) anthracene 0.0311 NA NA NA 0.98 U 1.9 U 1-1'-Biphenyl NA NA NA NA 2 U 1.9 U Carbazole NA NA NA NA 3.8 J 3.7 J 2-Chloronaphthalene NA NA NA NA 2 U 1.9 U Dibenzofuran NA NA NA NA 2 U 1.1 J 2,4-Dimethylphenol NA NA NA NA 9.8 U 6.5 J Fluoranthene 370 NA NA NA 2 U 0.74 J Fluorene 14,000 NA NA NA 2 U 1.5 J 2-Methylnaphthalene NA NA NA NA 2 U 1.9 U 2-Methylphenol NA NA NA NA 2 U 1.9 U Naphthalene NA NA NA NA 2 U 10 Phenanthrene NA NA NA NA 2 U 1.9 U Phenol 300 NA NA NA 2 U 1.7 J Pyrene 11,000 NA NA NA 2 U 1.9 U Total Petroleum Hydrocarbons

TPH-DRO NA NA NA NA 6,300 NA

TPH-ORO NA NA NA NA 500 Q NA

TPH-GRO NA NA NA NA 110 MHQ NA

Monitored Natural Attenuation Parameters Ethane NA NA NA 1.2 1.1 U NA Ethylene NA NA NA 0.46 F 1 U NA Methane NA NA NA 770 120 NA Nitrate-N 10,000 10,000 NA 35 U 830 MH NA Nitrite-N NA 1,000 NA NA 27 JMH NA Sulfate NA NA NA 1,000 770 JM NA Sulfide NA NA NA 3,000 UM 1,000 U NA Total Organic Carbon NA NA NA 14,000 10,000 NA Alkalinity NA NA NA 110,000 100,000 B NA

Dobbins Air Reserve Base

Marietta, Georgia

Screening Levels Georgia

ISWQS

EPA

MCL D5-W52 D5-W52

DUP D5-W53 D5-W54

Date December

February

February

December

December

Volatile Organic Compounds Benzene 71.28 5 478 1800 1500 101 0.054 U Chlorobenzene 21,000 100 NA NA NA NA NA 1,4-Dichlorobenzene 2,600 75 NA NA NA NA NA Ethylbenzene 28,718 700 NA 13 F 12 F NA NA 2-Hexanone NA NA NA NA NA NA NA Isopropylbenzene NA NA NA NA NA NA NA Methylcyclohexane NA NA NA NA NA NA NA Methyl tert-butyl ether NA NA NA NA NA NA NA Toluene 200,000 1,000 NA 11 U 11 U NA NA Total Xylenes NA 10,000 NA 22 U 22 U NA NA Semivolatile Organic Compounds Acenaphthene 990 NA NA NA NA NA NA Acenaphthylene NA NA NA NA NA NA NA Acetophenone NA NA NA NA NA NA NA Benzo (a) anthracene 0.0311 NA NA NA NA NA NA 1-1'-Biphenyl NA NA NA NA NA NA NA Carbazole NA NA NA NA NA NA NA 2-Chloronaphthalene NA NA NA NA NA NA NA Dibenzofuran NA NA NA NA NA NA NA 2,4-Dimethylphenol NA NA NA NA NA NA NA Fluoranthene 370 NA NA NA NA NA NA Fluorene 14,000 NA NA NA NA NA NA 2-Methylnaphthalene NA NA NA NA NA NA NA 2-Methylphenol NA NA NA NA NA NA NA Naphthalene NA NA NA NA NA NA NA Phenanthrene NA NA NA NA NA NA NA Phenol 300 NA NA NA NA NA NA Pyrene 11,000 NA NA NA NA NA NA Total Petroleum Hydrocarbons

TPH-DRO NA NA NA NA NA NA NA

TPH-ORO NA NA NA NA NA NA NA

TPH-GRO NA NA NA NA NA NA NA

Monitored Natural Attenuation Parameters Ethane NA NA NA 5.4 6.3 NA NA Ethylene NA NA NA 0.13 U 0.13 U NA NA Methane NA NA NA 1,800 J 1,300 J NA NA Nitrate-N 10,000 10,000 NA 35 U 35 U NA NA Nitrite-N NA 1,000 NA NA NA NA NA Sulfate NA NA NA NA NA NA NA Sulfide NA NA NA 130 U 130 U NA NA Total Organic Carbon NA NA NA 3,000 UM 3,000 UM NA NA Alkalinity NA NA NA 4,900 4,900 NA NA

Dobbins Air Reserve Base

Marietta, Georgia

Screening Levels Georgia

ISWQS

EPA

MCL D5-W55 D5-W56

Date December

February

December

October

Volatile Organic Compounds Benzene 71.28 5 11.2 9.9 0.054 U 1.0 U Chlorobenzene 21,000 100 NA NA NA 0.50 U 1,4-Dichlorobenzene 2,600 75 NA NA NA 1.0 U Ethylbenzene 28,718 700 NA 32 NA 0.50 U 2-Hexanone NA NA NA NA NA 5.0 U Isopropylbenzene NA NA NA NA NA 1.0 U Methylcyclohexane NA NA NA NA NA 1.0 U Methyl tert-butyl ether NA NA NA NA NA 0.50 U Toluene 200,000 1,000 NA 0.51 F NA 1.0 U Total Xylenes NA 10,000 NA 2.9 NA 0.50 U Semivolatile Organic Compounds Acenaphthene 990 NA NA NA NA 1.9 U Acenaphthylene NA NA NA NA NA 1.9 U Acetophenone NA NA NA NA NA 1.9 U Benzo (a) anthracene 0.0311 NA NA NA NA 1.9 U 1-1'-Biphenyl NA NA NA NA NA 1.9 U Carbazole NA NA NA NA NA 1.7 J 2-Chloronaphthalene NA NA NA NA NA 1.9 U Dibenzofuran NA NA NA NA NA 1.9 U 2,4-Dimethylphenol NA NA NA NA NA 9.5 U Fluoranthene 370 NA NA NA NA 1.2 J Fluorene 14,000 NA NA NA NA 1.9 U 2-Methylnaphthalene NA NA NA NA NA 1.9 U 2-Methylphenol NA NA NA NA NA 1.9 U Naphthalene NA NA NA NA NA 1.9 U Phenanthrene NA NA NA NA NA 1.9 U Phenol 300 NA NA NA NA 1.9 U Pyrene 11,000 NA NA NA NA 0.83 J Total Petroleum Hydrocarbons

TPH-DRO NA NA NA NA NA NA

TPH-ORO NA NA NA NA NA NA

TPH-GRO NA NA NA NA NA NA

Monitored Natural Attenuation Parameters Ethane NA NA NA 2.4 NA NA Ethylene NA NA NA 1.6 NA NA Methane NA NA NA 1,600 NA NA Nitrate-N 10,000 10,000 NA 35 U NA NA Nitrite-N NA 1,000 NA NA NA NA Sulfate NA NA NA NA NA NA Sulfide NA NA NA 130 F NA NA Total Organic Carbon NA NA NA 940 U NA NA Alkalinity NA NA NA 17,000 NA NA

Dobbins Air Reserve Base

Marietta, Georgia

Screening Levels Georgia

ISWQS

EPA

MCL D5-W57 D5-W57

DUP D5-W57

Date December

February

March

March

October

Volatile Organic Compounds Benzene 71.28 5 63 690 560 D 560 D 980 D Chlorobenzene 21,000 100 NA NA 1.8 1.8 1.4 J D 1,4-Dichlorobenzene 2,600 75 NA NA 1 U 2.4 5.0 U Ethylbenzene 28,718 700 NA 110 200 D 200 D 310 D 2-Hexanone NA NA NA NA 5 U 5 U 25 U Isopropylbenzene NA NA NA NA 14 15 18 D Methylcyclohexane NA NA NA NA 49 46 47 D Methyl tert-butyl ether NA NA NA NA 0.5 U 0.5 U 2.5 U Toluene 200,000 1,000 NA 4.4 U 6.8 7 13 D Total Xylenes NA 10,000 NA 84 300 330 950 Semivolatile Organic Compounds Acenaphthene 990 NA NA NA 1.9 U 1.9 U 1.3 J Q Acenaphthylene NA NA NA NA 1.9 U 1.9 U 1.9 U Q Acetophenone NA NA NA NA 1.9 U 1.9 U 1.9 U Benzo (a) anthracene 0.0311 NA NA NA 0.97 U 0.96 U 1.9 U Q 1-1'-Biphenyl NA NA NA NA 1.3 J 1.4 J 1.8 J Carbazole NA NA NA NA 1.6 J 1.6 J 2.2 J 2-Chloronaphthalene NA NA NA NA 1.9 U 1.9 U 1.9 U Dibenzofuran NA NA NA NA 1.9 U 1.9 U 0.79 J 2,4-Dimethylphenol NA NA NA NA 14 15 42 Fluoranthene 370 NA NA NA 1.9 U 1.9 U 0.75 J Q Fluorene 14,000 NA NA NA 1.9 U 1.9 U 1.1 J Q 2-Methylnaphthalene NA NA NA NA 3.4 J 4.1 J 7.9 J 2-Methylphenol NA NA NA NA 7.9 J 12 100 Naphthalene NA NA NA NA 11 14 45 Q Phenanthrene NA NA NA NA 0.96 J 1 J 1.7 J Q Phenol 300 NA NA NA 5.1 J 2.9 J 2.0 J Pyrene 11,000 NA NA NA 1.9 U 1.9 U 0.67 J Q Total Petroleum Hydrocarbons

TPH-DRO NA NA NA NA 3,200 3,400 NA

TPH-ORO NA NA NA NA 190 UQ 200 UQ NA

TPH-GRO NA NA NA NA 3,700 MHQ 3,600 MHQ NA

Monitored Natural Attenuation Parameters Ethane NA NA NA 2.5 9.5 8.6 NA Ethylene NA NA NA 1.5 1.9 1.6 NA Methane NA NA NA 960 1,900 M 1,800 NA Nitrate-N 10,000 10,000 NA 35 U 46 UH 46 UH NA Nitrite-N NA 1,000 NA NA 46 UH 46 UH NA Sulfate NA NA NA NA 130 U 800 UM NA Sulfide NA NA NA 130 U 3000 UM 1000 U NA Total Organic Carbon NA NA NA 3,000 UM 4,200 5000 NA Alkalinity NA NA NA 4,200 180,000 170,000 B NA

Dobbins Air Reserve Base

Marietta, Georgia

Screening Levels Georgia

ISWQS

EPA

MCL D5-W58

Date December

February

March

October

Volatile Organic Compounds Benzene 71.28 5 3.61 0.83 F 0.47 J 2.4 Chlorobenzene 21,000 100 NA NA 0.5 U 0.50 U 1,4-Dichlorobenzene 2,600 75 NA NA 1 U 0.75 J Ethylbenzene 28,718 700 NA 0.22 1 U 0.53 J 2-Hexanone NA NA NA NA 5 U 5.0 U Isopropylbenzene NA NA NA NA 0.7 J 3.9 Methylcyclohexane NA NA NA NA 1 U 1.0 U Methyl tert-butyl ether NA NA NA NA 0.5 U 0.50 U Toluene 200,000 1,000 NA 0.51 F 1 U 1.0 U Total Xylenes NA 10,000 NA 1 F 0.5 U 4.7 Semivolatile Organic Compounds Acenaphthene 990 NA NA NA 1.9 UQ 1.7 JQ Acenaphthylene NA NA NA NA 1.9 UQ 1.9 UQ Acetophenone NA NA NA NA 1.9 U 1.9 U Anthracene NA NA NA NA NA 0.77 JQ Benzo (a) anthracene 0.0311 NA NA NA 0.64 JQ 1.5 JQ 1-1'-Biphenyl NA NA NA NA 1.9 U 0.64 J Carbazole NA NA NA NA 1.9 U 2.8 J 2-Chloronaphthalene NA NA NA NA 1.9 U 1.9 U Chrysene NA NA NA NA NA 0.75 JQ Dibenzofuran NA NA NA NA 1.9 U 1.2 J 2,4-Dimethylphenol NA NA NA NA 9.5 U 9.6 U Fluoranthene 370 NA NA NA 4.6 JQ 9.2 JQ Fluorene 14,000 NA NA NA 1.2 JQ 1.8 JQ 2-Methylnaphthalene NA NA NA NA 1.9 U 1.9 U 2-Methylphenol NA NA NA NA 1.9 U 1.9 U Naphthalene NA NA NA NA 1.9 UQ 1.9 U Q Phenanthrene NA NA NA NA 1.9 UQ 1.9 U Q Phenol 300 NA NA NA 1.9 U 1.9 U Pyrene 11,000 NA NA NA 4.6 JQ 11 Q Total Petroleum Hydrocarbons

TPH-DRO NA NA NA NA 1300 NA

TPH-ORO NA NA NA NA 340 JQ NA

TPH-GRO NA NA NA NA 110 MH NA

Monitored Natural Attenuation Parameters Ethane NA NA NA NA 1.1 U NA Ethylene NA NA NA NA 1 U NA Methane NA NA NA NA 120 NA Nitrate-N 10,000 10,000 NA 35 U 46 UH NA Nitrite-N NA 1,000 NA NA 46 UH NA Sulfate NA NA NA 1,400 920 J NA Sulfide NA NA NA 940 U 1000 U NA Total Organic Carbon NA NA NA 1,600 1,900 NA Alkalinity NA NA NA 32,000 27,000 B NA

Dobbins Air Reserve Base

Marietta, Georgia

Screening Levels Georgia

ISWQS

EPA

MCL ITS-7

Date December

March

October

Volatile Organic Compounds Benzene 71.28 5 0.054 U 1 U 1.0 U Chlorobenzene 21,000 100 NA 0.5 U 0.50 U 1,4-Dichlorobenzene 2,600 75 NA 1 U 1.0 U Ethylbenzene 28,718 700 NA 1 U 0.50 U 2-Hexanone NA NA NA 5 U 5.0 U Isopropylbenzene NA NA NA 0.5 U 1.0 U Methylcyclohexane NA NA NA 1 U 1.0 U Methyl tert-butyl ether NA NA NA 0.5 U 0.50 U Toluene 200,000 1,000 NA 1 U 1.0 U Total Xylenes NA 10,000 NA 0.5 U 0.50 U Semivolatile Organic Compounds Acenaphthene 990 NA NA 1.9 UQ 1.9 U Acenaphthylene NA NA NA 1.9 UQ 1.9 U Acetophenone NA NA NA 1.9 U 1.9 U Anthracene NA NA NA NA 1.9 U Benzo (a) anthracene 0.0311 NA NA 0.96 UQ 1.9 U 1-1'-Biphenyl NA NA NA 1.9 U 1.9 U Carbazole NA NA NA 1. 9 U 1.9 U 2-Chloronaphthalene NA NA NA 1.9 U 1.9 U Chrysene NA NA NA NA 1.9 U Dibenzofuran NA NA NA 1.9 U 1.9 U 2,4-Dimethylphenol NA NA NA 9.6 U 9.6 U Fluoranthene 370 NA NA 1.9 UQ 1.9 U Fluorene 14,000 NA NA 1.9 UQ 1.9 U 2-Methylnaphthalene NA NA NA 1.9 U 1.9 U 2-Methylphenol NA NA NA 1.9 U 1.9 U Naphthalene NA NA NA 1.9 UQ 1.9 U Phenanthrene NA NA NA 1.9 UQ 1.9 U Phenol 300 NA NA 1.9 U 1.9 U Pyrene 11,000 NA NA 1.9 UQ 1.9 U Total Petroleum Hydrocarbons

TPH-DRO NA NA NA 110 NA

TPH-ORO NA NA NA 200 UQ NA

TPH-GRO NA NA NA 44 MH NA

Monitored Natural Attenuation Parameters Ethane NA NA NA 1.1 U NA Ethylene NA NA NA 1 U NA Methane NA NA NA 15 NA Nitrate-N 10,000 10,000 NA 930 M NA Nitrite-N NA 1,000 NA 46 U NA Sulfate NA NA NA 1,100 NA Sulfide NA NA NA 1000 U NA Total Organic Carbon NA NA NA 360 J NA Alkalinity NA NA NA 5100 B NA

Dobbins Air Reserve Base

Marietta, Georgia

Notes:

All units are µg/L – micrograms per liter NA – No ISWQS exist for this compound, or not analyzed ISWQS found in GAC 391-3-6-03 (VOCs and most SVOCs) and GAC 391-3-6-06 (acenaphthene, acenaphthylene, phenanthrene) Purple shading indicates that the ISWQS was below the Limit of Detection.

Orange shading indicates that the concentration is above MCL, but below ISWQS Yellow shading indicates that the concentration is above MCL and above ISWQS Bold indicates concentration detected above Limit of Detection.

Laboratory Qualifiers B – Blank contamination. The analyte was detected at concentrations above half the reporting limit in an associated blank.

D – The reported value is from a dilution.

F – Analytical result is estimate and is below the Limit of Quantitation.

H – The sample was prepped and analyzed beyond the specified holding time.

J – Estimated. The analyte was positively identified, the quantitation is an estimate.

M – Manually integrated compound.

Q – One or more quality criteria failed.

U – Undetected at the Limit of Detection.

Table 5 – Site DP005 Groundwater Monitoring Well GPS Locations

Monitoring Well ID North Latitude West Longitude D5-W35 33o 55’ 22.1” 84o 31’ 37.1” D5-W36 33o 55’ 21.8” 84o 31’ 36.2”

D5-W11R 33o 55’ 22.1” 84o 31’ 38.5” D5-W51 33o 55’ 21.1” 84o 31’ 40.3” D5-W56 33o 55’ 21.6” 84o 31’ 41.0” D5-W57 33o 55’ 20.6” 84o 31’ 40.6” D5-W58 33o 55’ 20.9” 84o 31’ 41.3”

ITS-7 33o 55’ 20.8” 84o 31’ 42.8” GWMW B10528 33o 55’ 18.7” 84o 31’ 38.1”

FIGURES

N

No Scale Determined

FIGURE 1

Site Location Map

Marietta, GA

Site Boundary

PROJ. #: 115.01.001 DATE: 07/07/2015

Image courtesy of Google Earth

D5-W48

D5-W9

D5-W37

D5-W47

D5-W10

D5-W11

D5-W26

WB10B11

D5-W58

D5-W47R

D5-W57

D5-W52

D5-W55

D5-W36

D5-W53

D5-W54

D5-W56

D5-W11R

D5-W50

(WB10587)

B10-MWL

D5-W35

ITS-7

D5-W49

ASTs

Approximate Area of

Former 25,000-Gallon

Fuel USTs

DVE

System

Suspected AVGAS Sludge

Burial Pit…