Final ANCSE Env Report.pdf

FINAL

Environmental Investigation Findings Report Arlington National Cemetery Southern Expansion

Prepared For:

HNTB Corporation 2900 South Quincy St Suite 200 Arlington, VA 22206

Prepared By:

Hana Engineers and Consultants, LLC 7501 Boulders View Drive Suite 620 Richmond, VA 23225

April 2017

Contract Number: W91236-14-D-0035 Revision Number: 0

Final Environmental Investigation Findings Report Arlington National Cemetery - Southern Expansion ii

APPROVAL PAGE

Approved by: ___________________________________ ________________ Jeff Zoeckler, P.E., P.G. Date Hana Engineers and Consultants, LLC (Hana) Senior Environmental Engineer

4/28/17 iv

Table of Contents

Introduction

Purpose and Scope

Site Background

Site Description and History

Previous Environmental Investigations and Actions

Potential Environmental Concerns

Report Organization

Physical Characteristics of the Site

Topography

Geology

Hydrogeology

Field Investigation

Pre-Investigation Activities

Environmental Investigation

Surveying

Investigative Derived Waste

Analytical Information

Data Validation

Sample Results

Soil

VOCs

SVOCs

Metals

DRO

GRO

PCBs

Dioxins/Furans

Asbestos

Summary

Debris Material v

Fate and Transport of Contaminants

Potential of Routes of Migration

Soil to Groundwater

Soil to Surface Water

Soil to Air

Contaminant Persistence

Risk Evaluation

Data Used in the HHRE

Exposure Assessment

Exposure Setting Characterization

Potential Exposure Pathways

Quantifying Exposure

Toxicity Assessment

Cancer Risk and Hazard Estimates

Uncertainty Assessment

Chemical Identification Uncertainty

Exposure Assessment Uncertainty

Toxicity Assessment Uncertainty

Summary of Results

Chemicals in Soil

Asbestos in Soil and Debris

References vi

List of Tables

Table 1: Environmental Analysis by Soil Sample Table 2: Soil Sampling Results Table 3: SVOC Exceedances in Soil Table 4: Asbestos Sampling Results Table 5: Environmental Analysis by Debris Sample Table 6: Chemicals of Potential Concern in Soil

List of Figures

Figure 1: Site Location Figure 2: Site Map Figure 3: Boring Locations Figure 4: Soil Sampling Results – Exceedances, West Figure 5: Soil Sampling Results – Exceedances, Central Figure 6: Soil Sampling Results – Exceedances, East Figure 7: Asbestos Sampling Results

Appendices

Appendix A: Photo Log Appendix B: Field Forms Appendix C: Survey Results Appendix D: IDW Sample Results Appendix E: Analytical Lab Reports Appendix F: Data Validation Reports Appendix G: ProUCL Data Reports vii

Acronyms and Abbreviations

% percent < less than > greater than A-E Architectural-Engineering ACM Asbestos Containing Material ANC Arlington National Cemetery ANCSE Arlington National Cemetery Southern Expansion AST Aboveground Storage Tank ASTM American Society of Testing and Materials bgs below ground surface BTEX Benzene, Toluene, Ethylbenzene, Xylenes c carcinogen CFR Code of Federal Regulations COPC Chemical of Potential Concern DoD Department of Defense DOT Department of Transportation DQO Data Quality Objective DRO Diesel Range Organics DUP Duplicate EA Environmental Assessment EIS Environmental Impact Statement EPC Exposure Point Concentration FOB Federal Office Building FSP Field Sampling Plan ft foot or feet GRO Gasoline Range Organics Hana Hana Engineers and Consultants, LLC HHRE Human Health Risk Evaluation HI Hazard Index HNTB HNTB Corporation HQ Hazard Quotient IDW Investigative Derived Waste LBP Lead-Based Paint MEC Munitions and Explosives of Concern viii mg/kg milligrams per kilogram MS Matrix Spike MSD Matrix Spike Duplicate n noncarcinogen

NAVD

NEPA

North American Vertical Datum National Environmental Policy Act

NEX Navy Exchange OSHA Occupational Safety and Health Administration PAH Polycyclic Aromatic Hydrocarbon PCB Polychlorinated Biphenyl PE Professional Engineer PG Professional Geologist pg/g picogram per gram PID Photoionization Detector PP Priority Pollutant PPE Personal Protective Equipment QAPP Quality Assurance Project Plan QA Quality Assurance QC Quality Control RAGS Risk Assessment Guidance for Superfund RfC Reference Concentration RfD Reference Dose RSL Regional Screening Level SOP Standard Operating Procedure SPT Standard Penetration Tests SVOC Semi-Volatile Organic Compound TCLP Toxicity Characteristic Leaching Procedure THQ Target Hazard Quotient TPH Total Petroleum Hydrocarbons TR Target Cancer Risk UCL Upper Confidence Limit UFP Uniform Federal Policy U.S. United States USACE United States Army Corps of Engineers USCS Unified Soil Classification System USEPA United States Environmental Protection Agency ix

UST Underground Storage Tank VDEQ Virginia Department of Environmental Quality VOC Volatile Organic Compound WHS Washington Headquarters Service

Introduction

Purpose and Scope This report has been prepared by Hana Engineers and Consultants, LLC (Hana) for HNTB Corporation (HNTB). HNTB is providing Architecture-Engineering (A-E) services for the Arlington National Cemetery (ANC) Southern Expansion (ANCSE), under contract with the United States (U.S.) Army Corps of Engineers (USACE) Norfolk District. Hana was contracted by HNTB to characterize hazardous materials and environmental impacts that may potentially affect the design and construction of the ANCSE. Environmental investigation activities were conducted concurrently with the geotechnical investigation activities which are discussed in a separate report. This report summarizes the results of the most recent sampling and discusses the nature and extent of impact, migration pathways, transport mechanisms and potential risk posed by site soils. The ANCSE Field Sampling Plan (FSP) (HNTB, 2016a) identifies the data collection activities and associated quality assurance (QA)/quality control (QC) measures specific to the environmental investigation.

Site Background ANC is a U.S military cemetery located in Arlington County, Virginia (Figure 1). Due to the need for additional burial space, land transfers are being completed to accommodate the ANCSE. The planned expansion area, previously known as the Navy Annex site, is located south of the ANC grounds and is approximately 46 acres (Figure 2). The site is bound on the north by ANC, on the south by Interstate 395 (I-395), on the east by Route 27/ Washington Boulevard, and on the west by residential properties fronting Oak Street.

The majority of the expansion site has been owned by the federal government since 1942.

Historical site use included barracks, office buildings, a service station, parking and roadways. The land parcels associated with the ANCSE include the Southgate Road Right of Way, the North Parcel (Navy Annex/Federal Office Building (FOB) 2/parking), the South Parking Parcel and the Navy Exchange (NEX) Parcel (Figure 2). The Air Force Memorial parcel, located immediately east of the transferred land, is not part of the

ANCSE.

Site Description and History Prior to the land transfer, this site included the Navy Annex / FOB2 complex, surface parking lots, and a NEX Service Station. All existing buildings on the site were demolished and removed during the land transfer process. The Navy Annex / FOB2 complex contained approximately one million square feet (ft) of office space occupied by various military service and defense agency tenants, including the U.S. Marine Corps, the Department of the Navy, and the Ballistic Missile Defense Agency. The Navy Annex / FOB2 complex consisted of a head house and eight four-story wings constructed between 1940 and 1948. Wing 8 was demolished in 2004 for construction of the Air Force Memorial. The remainder of the FOB2 complex was demolished in 2013.

Due to historical use of the site, potential environmental impacts exist, including the potential release of hazardous substances related to underground storage tanks (USTs), aboveground storage tanks (ASTs), transformers, solid waste storage, lead-based paint (LBP), and asbestos containing material (ACM). These potential releases have previously been evaluated through numerous environmental investigations and studies at the site.

Additionally, several remedial activities have been conducted in order to mitigate environmental impacts from known releases at the site. A chronological summary of relevant environmental studies, investigations and remedial activities is provided in Section 1.2.2.

Previous Environmental Investigations and Actions Previous environmental studies, investigations and remedial activities were evaluated in the ANCSE Opportunities and Constraints – Hazardous Materials Document (HNTB, 2015). These documents are summarized below:

Environmental Assessment, Navy Annex FOB #2, Land Transfer Plan (Washington Headquarters Service [WHS], 2011)

The Environmental Assessment (EA) evaluated environmental impacts related to the proposed Land Transfer Plan for Navy Annex/FOB2 property and the eventual expansion of ANC. The EA evaluated numerous potential environmental consequences related to the land transfer in accordance with the National Environmental Policy Act (NEPA) of 1969, including socio-economic conditions, cultural resources, transportation systems, infrastructure/utilities, and physical/biological resources. The EA concluded that the proposed land transfer would result in No Impact or No Significant Impact to the resources evaluated. Hazardous materials are a component of the physical/biological resources evaluation, and this section is the portion of the EA relevant to this document.

The hazardous materials evaluation addressed the potential for hazardous substances to be present at the site based on activities known to have occurred at the site. This included an evaluation of:

• USTs/ASTs

• ACM

• LBP

• Polychlorinated Biphenyls (PCBs)

• Munitions and Explosives of Concern (MEC)

• Hazardous Waste Storage and Handling Areas

• Medical and Biohazard Waste

• Radioactive Materials and Mixed Waste

• Solid Waste

• Spills and Leaks

• Mercury

• Groundwater Monitoring Wells

Numerous ASTs and USTs were identified at the FOB2 complex and the NEX Service Station Parcel. A documented release from a former UST at the NEX parcel had been addressed through the Virginia Department of Environmental Quality (VDEQ) UST Program. At the time of the EA (prior to FOB2 demolition), ACM and LBP were known to be present at the FOB2, but the associated structures appeared to be in good condition and abatement was not recommended at the time. However, ACM and LBP remediation/abatement was performed during demolition of the FOB2 complex. Electrical transformers at the site were reported to be PCB-free. Only minor spills and leaks were documented at the site and these had been properly contained (Gallup, 2009). Overall, the EA assigned a finding of No Impact for hazardous materials.

Finding of No Significant Impact (Department of Defense [DoD], 2012)

Based on the results of the EA for the Land Transfer Plan, the DoD found that the Land Transfer Plan was not a major Federal action significantly affecting the quality of the human environment. In accordance with NEPA, this finding indicates that an environmental impact statement (EIS) is not required.

Building Debris in Soil Assessment (WHS, 2013)

In July 2013, an assessment of building demolition debris was conducted as part of the demolition of the Navy Annex/FOB2 site and preparation of the site for future use by ANC.

All debris areas were located on South Parking and NEX parcels, where Quarter K Barracks were previously located until demolition of these structures in 1970-1971.

Numerous excavations and test pits were conducted to characterize the nature and extent of debris and to test debris for suspect ACM.

The presence of ACM related to floor tile, mastic, cement boards, loose fibrous insulation, and laminate flooring was verified at numerous locations. Laboratory analysis of bulk samples indicated presence of chrysotile asbestos ranging from < 1 percent (%) to 80%.

The letter report estimated the total quantity of soil containing ACM and non-asbestos building debris to be approximately 60,000 cubic yards. The report presented possible response actions: 1) removal of soil with ACM and building debris or 2) leave the site in its current condition. Under the first response action, two options were considered:

complete removal of soil containing ACM and non-asbestos building debris, or sieving soil and debris and then disposing of the sieved material. Ultimately, the sieving approach was selected and implemented as described in future reports (WHS, 2014; Watermark, 2014a,b,c; Watermark 2015a,b,c,d).

Surge Stone Investigation Report (Land Strategies, Inc. [LSI], 2013)

The demolition contractor for the FOB2/Navy Annex site unearthed an area of surge stone at the NEX parcel during demolition activities. Additional investigation into the extent and purpose of the surge stone and an assessment of environmental impacts, was subsequently conducted. The results of the investigation indicated the surge stone was comprised of recycled concrete ranging in size from less than (<)1 inch to greater than

(>)12 inches. It was estimated that approximately 14,000 cubic yards of stone was present and that it was likely used to backfill a former UST. Water present in the surge stone pit was attributed to accumulation of surface water, and it did not appear to be part of an engineered system. Laboratory tests of a water sample contained low-level detections of some petroleum constituents. No additional remedial activities were recommended for the surge stone at the time.

UST Closure Report (LSI, 2014)

The demolition contractor for FOB2 / Navy Annex site unearthed a UST at the NEX parcel, referred to as NEX-UST1 during demolition activities. All registered ASTs and USTs were thought to have been previously removed upon closure of the NEX station. The tank was determined to be a former gasoline tank with a capacity of approximately 5,000 gallons.

The tank was excavated, cleaned, and removed. Approximately 2,000 cubic yards of impacted soil surrounding the tank were also removed and properly disposed at an off-site facility. VDEQ was notified of the tank and removal activities. No additional remedial activities were recommended for NEX-UST1 at the time.

Transformer Spill Cleanup Report (LSI, 2014)

During demolition activities in August 2013, the demolition contractor for the FOB2/Navy Annex site unearthed a concrete vault containing two out-of-service transformers. Upon opening the vault, a small quantity (estimated to be 10 gallons) of oil leaked onto concrete debris and into the shallow subsurface. The demolition contractor immediately responded with spill containment measures and cleanup procedures. Subsequently, the transformer oil was field tested and verified to contain PCBs. As a result, approximately 25 tons of soil and concrete were excavated and removed from the spill area and properly disposed off-site. Confirmation soil samples were collected in the excavation pit, and PCB levels were below applicable state and federal screening levels.

ACM Remediation (WHS, 2014; Watermark 2014a,b,c ; Watermark 2015a,b,c,d)

In 2014, WHS solicited design-build contractors for the design, remediation planning, buried demolition debris removal (in soil), and site restoration of specific areas of the site within the South Parking and NEX Parcels. The work was described as removal and disposal of asbestos and debris to a depth of 12 ft below grade. The scope generally considered two options: 1) partial removal of debris >1 inch, and 2) complete removal of all soil containing debris and hazardous material (i.e., residual ACM in soil/debris).

Ultimately, Watermark was selected to design, plan, and execute the project under option

1. Based upon review of available documentation, the remedial approach was a combination of the following excavation and sifting procedures, depending on the specific area:

1) Raking – Specific areas were raked using the teeth of an excavator bucket across the soil to remove and stockpile debris >1 inch. Areas selected for raking appear to have been identified as areas where debris stockpiles were previously “dispersed”, indicating that debris was only surficial in nature. According to the site drawings, raking with the teeth of the bucket continued until debris was no longer visible.

2) Removal and Sifting – removal of soil to the maximum depth identified on the Issued for Construction (IFC) drawings. Maximum depths were identified as 5 ft or 12 ft, depending on the specific area. During excavation, soil was sifted to remove debris >1 inch. Soil (including debris <1 inch) was then backfilled and compacted, per specifications.

The specific locations where raking, removal and sifting occurred are shown on the As- Built Drawings. Additionally, other features of the remediation project are included in the hand-marked “red-line” drawings provided in the field documentation (Watermark, 2015c).

A detailed project completion report with clear documentation of the remediation activities was not available. However, based on copies of field documentation, remediation activities (including mobilization and demobilization) began in September 2014 and were completed in January 2015. According to production reports, waste streams were identified and tracked as recyclable masonry, construction and demolition debris, non-friable ACM, and friable ACM. This remediation project entailed removal of large quantities of ACM and other debris from the site. However, a clear summary of quantities of each waste stream is not provided, and quantities of soil/debris (<1 inch) returned to the excavation at each specific area are not readily discernable. The total quantities of each waste stream, as well as backfill and material returned to the excavation, represents a data gap that should be discussed and verified with project stakeholders. It should also be noted that ambient air and personnel monitoring for asbestos fibers was conducted throughout the project. The Air Monitoring Report concluded that engineering controls implemented by the excavation contractor were sufficient in keeping ambient air and personal levels below relevant U.S. Environmental Protection Agency (USEPA), VDEQ and Occupational Safety and Health Administration (OSHA) standards.

A “burn pit” area was noted on marked-up drawings included in the Final Report for debris and ACM removal activities, performed by WHS (Watermark 2015a,b,c,d). However, there was no historical information or operational description of the “burn pit” provided in the reports. Therefore additional investigation was performed in this area, to include test pitting and dioxin/furan sampling. A discussion of the investigation plan and the soil sampling results are provided in Sections 3.2 and 4.1, respectively.

In addition to the ACM and debris removal, petroleum-impacted soil was removed from the NEX parcel (Watermark, 2015b). Confirmation samples were collected from the floors and sidewalls of the excavation. A clear summary of the quantity of petroleum-impacted material removed from the site is not provided.

Potential Environmental Concerns As discussed above, there have been documented releases of hazardous substances at the site, and most impacts from these releases have been remediated. However, based on past site activities, there is the potential for residual impacts from identified releases, as well as the possibility of impacts from previously unidentified releases. The impacts could warrant special soil handling/disposal and health and safety measures during construction. Potential areas of environmental concern are discussed below.

Petroleum Impacts (NEX and Former FOB2 Parcels)

Releases have occurred from former tanks (FOB2 and NEX parcels) and transformers (FOB2). Remedial activities were implemented to address these releases and no further actions are required as of this time; however, the potential for residual impacts does exist.

These potential impacts are expected to be minimal and manageable during design and construction.

Debris Containing Residual ACM (South Parking and NEX Parcels)

A significant remedial action for removal of soil and debris containing ACM was implemented in 2014 and 2015. However, buried debris (<1 inch) and soil was placed back into some excavations and compacted during the remedial activities, in accordance with the project specifications. Based on the data provided, it is unclear if the debris (<1 inch) contained residual ACM since the size of the material is not indication of the presence or absence of ACM. Additionally, the quantities of debris and ACM removed versus the material placed back into the excavations are not clear from the available field reports and drawings.

Report Organization The report is organized as follows:

• Section 2 presents the physical characteristics of the site.

• Section 3 present a summary of field investigation activities.

• Section 4 summarizes the analytical results and describes the nature of impact at the site.

• Section 5 discusses the fate and transport of site-specific constituents of interest.

• Section 6 discusses the risk screening process.

• Section 7 presents a summary of the findings and conclusions of the environmental investigation.

• Section 8 present a list of references for this report.

Physical Characteristics of the Site

This section presents a summary of the physical characteristics of the site, including geography, topography, geology and hydrogeology. The summary is based on previous investigations conducted at the site.

Topography The location of the site is relatively flat surrounded by moderate to steep slopes to the east and southeast. Topography within the land transfer area rises from approximately 40 ft above sea level at the east edge to a height of 155 ft at the ridge.

Geology ANC is located within the Atlantic Coastal Plain Physiographic Province of Virginia, which consists of a series of south-easterly dipping, relatively consolidated sand and clay deposits of the tertiary and cretaceous ages. The crystalline rock of the Piedmont Physiographic Province exists approximately 250 ft below this Coastal Plain.

The Potomac Formation of the late Cretaceous Period was mostly deposited in fluvial and deltaic environments, and is the primary formation underlying the ANCSE project site.

The Potomac Formation consists of discontinuous interbedded sand and clay layers. The sand deposits are light gray to greenish gray in color, and fine to coarse grains with varying amounts of silt and clay. The clay deposits of this formation are mottled red to reddish-brown in color and are commonly referred to as “Marine Clay”. They are characterized as stiff, over consolidated, and highly moisture sensitive.

In general, the subsurface stratigraphy encountered at the ANCSE site consists of the following three layers in descending order from the surface: 1) existing fill, 2) marine clay, and 3) clayey fine sand. More detailed discussion of these soil layers is provided below.

Additional detail on the site geology is provided in the Geotechnical Findings Report, which is being prepared in conjunction with this document.

Existing Fill Layer

The existing fill layer is up to 30 feet thick and consists of varying composition of both sand and clay with roots and asphalt fragments. The thickest portions of the fill layer are located at the higher elevations, encountered in soil borings that were performed at the former Navy Annex/FOB2 Main Parcel property and the western portions of the South Parking Parcel. The fill layer was much thinner in the eastern portion of the South Parking Parcel and is visibly different from the fill at the Navy Annex/FOB2 Main Parcel. The fill in this area consists of construction debris, such as brick, concrete, wood and metal, ranging in thickness from 0 to approximately 8 feet. ACM is present within this debris at some locations.

Marine Clay

Naturally deposited marine underlies the existing fill layer. The marine clay layer may be encountered approximately 30 ft deep or immediately below the existing grade. The marine clay layer is characterized as very stiff, over consolidated, and highly moisture sensitive. Although this clay may exhibit considerable strength in its natural state, there are certain attributes of this clay (i.e., fissures and slickensides) that will result in a significant strength loss when disturbed. This clay formation is brittle and has a blocky structure, so fissures and slickenside surfaces are prevalent within the clay formation.

Sand

Underneath the marine clay layer, a sand layer with varying amounts of fines is expected.

All geotechnical borings performed were terminated within this layer so the thickness of the sand layer is unknown.

Hydrogeology Groundwater was not encountered in most of the soil borings completed at the site.

However, perched water conditions were encountered at a few locations, due to the interface between the coarse grained existing fill layer and marine clay layer at both the high and low elevation areas of the project site. Actual depth to perched groundwater ranged from approximately 25 – 40 ft bgs across the site.

Field Investigation

This section describes the tasks completed by Hana as part of the environmental investigation. All field activities were coordinated with HNTB, ANC, and USACE Norfolk District. A photographic log documenting the field work is presented in Appendix A.

Pre-Investigation Activities Prior to mobilization, all boring and test pit location were marked with a labeled stake, and utility clearance was conducted utilizing three lines of evidence. First, Miss Utility of Virginia 811 was contacted at least 72 hours in advance of land disturbance to mark underground utilities. Second, personnel knowledgeable of the site were consulted, and available site plans were reviewed to identify existing utilities within the Site. Finally, a private utility contractor (GPRS, Inc.) located and marked underground utilities within the marked areas.

Environmental Investigation Field activities began on 12 September 2016. The environmental investigation activities were conducted concurrently with the geotechnical investigation and focused primarily on soil 0 to 12 ft below ground surface (bgs), which is considered the approximate limit of excavation during future construction activities.

The environmental investigation field work included:

• Standard penetration test (SPT) borings,

• Test pits, and

• Geoprobe borings.

The SPT borings were competed by Fishburne Drilling, Inc., and the test pits and Geoprobe borings were completed by A-Zone Environmental Services, LLC. The procedures for these field investigation activities are described in the FSP (HNTB, 2016a).

Completed boring locations are shown on Figure 3. These locations were chosen based on site features such as the previously identified ACM burial locations or fuel tanks, visual observations made in the field, and to achieve adequate site coverage. In total, 24 SPT borings, 43 test pits, and 11 Geoprobe borings were completed across the site.

A registered Professional Geologist (PG) or Professional Engineer (PE) with knowledge of soil classification observed and logged the soils at all SPT, test pit, and Geoprobe locations. Soil were logged for lithology, observed for evidence of impact (e.g., staining, odor, debris) and screened with a photo-ionization detector (PID) if evidence of impact was observed. The soil logs are included in Appendix B.

Samples were not collected at all SPT, Geoprobe, and test pit locations. Soil samples were generally not collected if the material appeared to be native and/or there was clearly no evidence of impact. However, soil samples were collected to achieve adequate spatial coverage across the site, regardless of evidence of impact. Soil samples were collected and visually classified per the Unified Soil Classification System (USCS) in accordance with the procedures in American Society of Testing and Materials (ASTM) D2487-06.

In the absence of evidence in impact, surface soil samples were generally collected from 0 to 2 ft bgs and subsurface samples from 4 to 8 ft bgs. Evidence of impact was not observed deeper than 8 ft bgs; therefore, no samples were collected in the 8 to 12 ft bgs interval.

Select soil samples were analyzed for:

• Volatile Organic Compounds (VOCs) by USEPA SW-846 Method 8260B/C

• Semi-VOCs (SVOCs) by USEPA SW-846 Method 8270D

• Priority Pollutant (PP) Metals (minus mercury) by USEPA SW-846 Method 6010C

• Mercury by USEPA SW-846 Method 7471A/B

• Total Petroleum Hydrocarbons (TPH)-Diesel Range Organics (DRO) by USEPA

SW-846 Method 8015C

• TPH-Gasoline Range Organics (GRO) by USEPA SW-846 Method 8015C

• Total PCBs by USEPA SW-846 Method 8082A

• Dioxins Furans by USEPA SW-846 Method SW8290A

• Asbestos in Soil by Method ASTM D7521-13

Dioxin/furan samples were planned for collection in the previously identified “burn pit” area locations (T-23, T-24, T-27, T-40). The “burn pit” is located in the southeast portion of the South Parking Parcel, and was noted on drawings in reports for the previously completed building demolition, debris, and ACM removal activities, performed by WHS (WHS, 2014; Watermark 2014a,b,c ; Watermark 2015a,b,c,d). However, there was no historical information or operational description of the “burn pit” provided in the reports.

Dioxin/furan samples were also collected in locations (T-14, T-19, T-22, T-25, T-31, T-25, T-38) where evidence of potential burning was observed (e.g., charred debris, ash) in the field.

The primary purpose of the environmental test pits was to verify the nature and extent of residual ACM material, particularly in the south parking parcel. If suspected ACM debris was encountered, bulk samples of debris material was collected for bulk asbestos by USEPA 600/R-93/116. Sampling for asbestos in soil required specific procedures, as described in ASTM D7521-13. These procedures are included in the Final Uniform Federal Policy for Quality Assurance Project Plan (UFP-QAPP) (HNTB, 2016b). All test pits were observed for other potential environmental impacts as well and these items were noted on the soil logs.

Field QC samples were collected as outlined in FSP with 1 field duplicate collected per 10 investigative samples, and 1 Matrix Spike (MS) and Matrix Spike Duplicate (MSD) sample collected per 20 investigative samples.

Surveying All exploration locations were surveyed by a licensed surveyor following completion of field work in accordance with the Standard Operating Procedure (SOP) included in the UFP-QAPP (HNTB, 2016b). Elevation is reported in accordance with NAVD 88, and horizontal coordinates are reported in the Virginia State Plane Coordinate System.

Accuracy for boring locations is plus or minus 1 ft horizontal and plus or minus 0.01 ft vertical. The results of the survey are included in Appendix C.

Investigative Derived Waste Un-impacted soil cuttings from SPT, test pits and Geoprobe were placed back into the excavation, and the surface was returned to its original condition to the extent possible.

All soil cuttings suspected of potential contamination (based on field observations) were treated as investigative derived waste (IDW) and containerized in U.S. Department of Transportation (DOT)-approved 55-gallon drums. Soil cuttings in heavily trafficked areas, such as roadways or sidewalks were also containerized and moved to the staging area.

The soils were sampled and analyzed for Benzene, Toluene, Ethylbenzene, and Xylenes (BTEX); TPH-DRO; PCBs; and Toxicity Characteristic Leaching Procedure (TCLP) Metals. The results of the IDW sampling are included in Appendix D. Based on the results of IDW sampling, the soil was considered suitable for spreading on the surface, within the site footprint. Therefore, IDW was spread on the Navy Annex/FOB2 parcel.

Disposable sampling supplies and expendable Personal Protective Equipment (PPE) were containerized in trash bags and disposed as non-hazardous waste at the end of the project.

Analytical Information Soil and debris samples were shipped under chain of custody to the following laboratories:

• Empirical Laboratories, LLC 621 Mainstream Drive, Suite 270 Nashville, TN 37228 Main: 615.345.1115

• EMS Analytical, Inc. (asbestos) 200 Route 130 North Cinnaminson, NJ 08077 800.220.3675

• Cape Fear Analytical (dioxins and furans) 3306 Kitty Hawk Road, Suite 120 Wilmington, NC 28405 910.795.0421

Data Validation All laboratory-generated reports and QC data were reviewed and validated by a qualified 3rd party validator (TLI Solutions, LLC) in general accordance with the USEPA National Functional Guidelines. The USEPA National Functional Guidelines are specific to Contract Laboratory Program methods and were modified as necessary to comply with the actual methods used. Analytical and QA/QC data were reviewed to determine if the data are usable or required additional qualification. TLI Solutions, LLC produced a data validation report for each discrete report received from each laboratory.

Sample Results

Analytical results from the environmental field investigation are summarized in this section. The laboratory analytical data are provided in Appendix E, and the data validation reports are provided in Appendix F.

Soil As described in Section 3.2, the analysis for each soil sample was selected based on its location at the site and if any impacts were observed. Table 1 below presents the analyses completed by location and depth.

Table 1: Environmental Analysis by Soil Sample

Sample ID Sample Depth (ft)

Analysis VOCs SVOCs Metals DRO GRO PCBs Dioxins/

Furans Asbestos

ANCSE-B010 2-4 X

ANCSE-B013 5-9 X X X X

ANCSE-G001

0-2 X X X

4-8 X X X

ANCSE-G002

0-2 X X X

4-8 X X X

ANCSE-G003

0-2 X X X X X X

4-8 X X X X X X

ANCSE-G004

2-3 X X X

4-8 X X X

ANCSE-G005

0-2 X X X X X X

4-8 X X X X X X

ANCSE-G006

0-2 X X X

4-8 X X X

ANCSE-G007

0-2 X X X

0-2 DUP X X X

4-8 X X X

ANCSE-G008

0-2 X X X X X X

0-2 DUP X X X X X X

4-8 X X X X X X

ANCSE-G009

0-2 X X X X X X

4-8 X X X X X X

ANCSE-G010

0-2 X X X

4-8 X X X

ANCSE-G011

0-2 X X X X X X

4-8 X X X X X X

ANCSE-T006 2-4 X X X

Sample ID Sample Depth (ft)

Analysis VOCs SVOCs Metals DRO GRO PCBs Dioxins/

Furans Asbestos

ANCSE-T009 2-4 X X X

ANCSE-T011 2-3 X

ANCSE-T012 0-2 X

ANCSE-T013 0-2 X X X

ANCSE-T014 2-6 X X X X X

ANCSE-T019

0-2 X 3-5 X X X

ANCSE-T022 0-2 X X

ANCSE-T023

3-6 X X X X X

3-6 (WM) X

ANCSE-T024 3-5.5 X X X X X

ANCSE-T025 3-4 X X X X X

ANCSE-T027 3-5 X X X X X

ANCSE-T031 2-5 X X X X X X X

ANCSE-T032 3-4 X X

ANCSE-T035 3-5 X X X X X X

ANCSE-T038

2-5 X X X X X

2-5 DUP X X X X X

ANCSE-T039 3-5 X

ANCSE-T040

2-5 X X X X X

2-5 DUP X X X X X

ANCSE-T041 2.5-5 X

ANCSE-T042 2-3 X X X

Note:

DUP – duplicate

Screening criteria used to evaluate the analytical results are the May 2016 USEPA Regional Screening Levels (RSLs) for Residential and Industrial Soils (USEPA, 2016).

While the site is intended only for industrial use, the residential soil criteria was added for comparison. Table 2 presents the summary of the analytical results, except for the asbestos in soil which is presented in Table 3. Figures 4 through 7 present industrial RSL exceedances by sample location. The results of the sampling are summarized below.

VOCs Sixteen soil samples, including one duplicate, one MS, and one MSD, were collected and analyzed for VOCs by USEPA SW-846 Method 8260B/C. There were several detections of 2-butanone and acetone; however, all detections were below screening levels. No other VOCs were detected.

SVOCs Forty-five soil samples, including four duplicates, two MSs, and two MSDs, were collected and analyzed for SVOCs by USEPA SW-846 Method 8270D. Multiple analytes were detected with several exceeding screening levels. Table 3 presents the SVOC exceedances by analyte and depth.

Table 3: SVOC Exceedances in Soil

Analyte

Screening Criteria (mg/kg)

Exceedances/Total Samples of RSLs by Depth (ft bgs)1

Maximum Detected

Concentration (mg/kg)

Detected Depth (ft bgs)

Industrial Residential Industrial

RSL

Residential

RSL 0-2 >2 0-2 >2

Benzo(a)anthracene 2.9 0.16 0/11 3/26 2/11 13/26 26.4 (3-5.5)

Benzo(a)pyrene 0.29 0.016 3/11 8/26 5/11 14/26 19.6 (3-5.5)

Benzo(b)fluoranthene 2.9 0.16 0/11 3/26 4/11 13/26 24.6 (3-5.5)

Benzo(k)fluoranthene 29 1.6 0/11 0/26 0/11 3/26 8.35 (3-5.5)

Chrysene 290 16 0/11 0/26 0/11 1/26 23.5 (3-5.5)

Dibenz(a,h)anthracene 0.29 0.016 0/11 2/26 0/11 4/26 3.05 (3-5.5)

Dibenzofuran 100 7.3 0/11 0/26 0/11 1/26 18.5 (3-5.5)

Indeno(1,2,3-cd)pyrene 2.9 0.16 0/11 3/26 3/11 12/26 12.6

(3-5.5)

Naphthalene 17 3.8 0/11 0/26 0/11 1/26 5.99 (3-5.5)

Note:

mg/kg – milligrams per kilogram

1. Count does not include duplicate or MS/MSD samples.

Metals Forty-seven soil samples, including four duplicates, two MSs, and two MSDs, were collected and analyzed for Priority Pollutant (PP) Metals by USEPA SW-846 Method 6010C and USEPA SW-846 Method 7471A/B. Arsenic and lead were detected at concentrations above screening levels. Arsenic was detected in 11 surface soil (0-2 ft bgs) and in 20 subsurface soil samples (>2 ft bgs) at concentrations ranging from 3.21 to

18.3 mg/kg, which exceed the industrial RSL of 3.0 mg/kg.

Lead was detected in one subsurface soil sample (ANCSE-T023; “3-6 (WM)”) at a concentration of 964 mg/kg which exceeds the industrial RSL of 800 mg/kg. This sample was collected due to the observation of a white material in the soil at this depth. An additional sample was collected at this location without the white substance and the concentration of lead (183 mg/kg) did not exceed screening levels. No other metals were detected above screening levels.

DRO

Twenty-four soil samples, including three duplicates, one MS, and one MSD, were collected and analyzed for TPH-DRO by USEPA SW-846 Method 8015C. Two subsurface soil samples with concentrations of 912 and 1860 mg/kg exceeded the residential RSL of 250 mg/kg, but were below the industrial RSL of 3,300 mg/kg. All other detections were below screening levels.

GRO

Sixteen soil samples, including one duplicate, one MS, and one MSD, were collected and analyzed for TPH-GRO by USEPA SW-846 Method 8015C. One subsurface soil sample with a concentration of 16.2 mg/kg exceeded the residential RSL of 8.2 mg/kg, but was below the industrial RSL of 42 mg/kg. All other detections were below screening levels.

PCBs Twenty-six soil samples, including two duplicates, one MS, and one MSD, were collected and analyzed for total PCBs by USEPA SW-846 Method 8082A. Arocolor-1260 was detected in two surface soil samples at concentrations of 0.27 and 0.495 mg/kg which exceed the residential RSL of 0.24 mg/kg, but are below the industrial RSL of 0.99 mg/kg.

No other PCBs were detected.

Dioxins/Furans Dioxin/furan samples collected in the previously identified “burn pit” area locations (T-23, T-24, T-27, T-40) and in locations (T-14, T-19, T-22, T-25, T-31, T-25, T-38) where evidence of potential burning was observed (e.g., charred debris, ash) in the field. Fifteen soil samples, including two duplicates, one MS, and one MSD, were collected and analyzed for dioxins/furans by USEPA SW-846 Method SW8290A. No detected analytes exceeded industrial RSLs. The following analytes exceeded residential RSLs:

• Four subsurface soil samples with concentrations of 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin ranging from 122–314 picograms per gram (pg/g) exceeded the residential RSL of 100 mg/kg.

• Two subsurface soil samples with concentrations of total tetrachlorodibenzo-p-dioxin ranging from 8.33–10.6 pg/g exceeded the residential RSL of 4.8 mg/kg.

Although there was visual evidence of potential burning, soil sample results generally do not indicate elevated levels of dioxins/furans.

Asbestos Twenty-four soil samples, including two duplicates, one MS, and one MSD, were collected and analyzed for asbestos in soil by Method ASTM D7521-13. These samples were collected only within the previously identified ACM soil removal areas. The complete asbestos results are presented in Table 4. Asbestos was detected in 15 of the soil samples at polarized light microscopy (PLM) weighted concentrations ranging from less than 0.25 % to 2%. Only one sample however had concentrations of asbestos >1 %. In all cases, the asbestos detected was chrysotile. These results will be further discussed in Section 7.

Summary Due to the future industrial land use of the ANCSE project site, only exceedances of industrial RSLs will be addressed in the remainder of this report. The following exceedances of the industrial RSL occurred in soils:

• SVOCs o Surface Soils

27% of surface soil samples exceeded the industrial RSL for benzo(a)pyrene.

o Subsurface Soils 7.7% of subsurface soil samples exceeded the industrial RSL for dibenz(a,h)anthracene.

11.5% of subsurface soil samples exceeded the industrial RSLs for benzo(a)anthracene, benzo(b)fluoranthene, or indeno(1,2,3-cd)pyrene.

30.8% of subsurface soil samples exceeded the industrial RLS for benzo(a)pyrene.

o The highest SVOC concentrations were observed in the parking parcel (Figure 5).

• Metals o Surface Soils 100% of surface soil samples exceeded the industrial RSL for arsenic.

o Subsurface Soils

77% of subsurface soil samples exceeded the industrial RSL for arsenic.

3.8% of subsurface soil samples exceeded the industrial RSL for lead. This sample was collected due to an observation of a white material in the soil. The corresponding sample from the same location without the white material was below screening levels.

No industrial RSL exceedances occurred for VOCs, TPH-DRO, TPH-GRO, PCBs, and dioxins/furans in surface or subsurface soil samples. These exceedances will be further addressed in Section 7.

Debris Material Table 5 presents the debris samples which were collected and analyzed for bulk asbestos by USEPA 600/R-93/116.

Table 5: Environmental Analysis by Debris Sample

Sample ID Sample Depth (ft) Bulk Asbestos

ANCSE-T006 2-4 X

ANCSE-T009 2-4 X

ANCSE-T011 2-3 X

ANCSE-T014 2-6 X

ANCSE-T019 0-2 X

ANCSE-T022 0-2 X

ANCSE-T023 3-6 X

ANCSE-T031 2-5 X

ANCSE-T038 2-5 X

ANCSE-T040

2-5 X

2-5 DUP X

ANCSE-T041 2.5-5 X

ANCSE-T042 2-3 X

ANCSE-T043 2-3 X

Note:

DUP – duplicate

Of the 14 debris samples analyzed, 5 contained asbestos ranging from 10 to 20% chrysotile. These results are presented in Table 4 along with the asbestos in soil results.

These results are further evaluated in Section 7.

Fate and Transport of Contaminants

This section evaluates the fate and transport of chemicals detected in soil samples collected at the site to support the identification of potential exposure routes through which human receptors may be exposed.

Potential of Routes of Migration Soil to Groundwater

The migration of a contaminant from soil to underlying groundwater is affected by the physical and chemical properties of the contaminant and the subsurface, including the following:

• Sorption - The mobility contaminants through infiltrating precipitation will be retarded by the sorption properties of each contaminant and the soil matrix.

Chemicals tend to adsorb to clays and tend not to adsorb to sand and rock.

Inorganic chemicals may also adsorb to hydroxides and oxides in soil.

• Dissolution – This is the process by which a chemical moves into aqueous solution, which is governed be the inherent solubility of the chemical and the geochemical properties (pH, oxidation reduction potential and co-precipitates) of the aqueous environment.

• Migration within groundwater – Migration of a contaminant within groundwater occurs through advection and dispersion. As with infiltration, the rate of movement through groundwater is slowed by sorption, a process referred to as retardation.

The potential for migration of contaminants from soil to groundwater is minimal, based on the following:

• Depth to groundwater in piezometers at the site ranged from 25 to 40 ft bgs. Soil borings indicate that this groundwater was “perched” on clay from the Potomac Formation.

• Sorption properties of chemicals – the types of contaminants (metals and SVOCs) detected in soil tend to adsorb to soil

• Sorption properties of site soil – the clays of the Potomac Formation tend to adsorb chemicals

The potential for exposure from the soil to groundwater pathway is also minimized because groundwater is not used for drinking water purposes in the area.

Soil to Surface Water Migration of contaminants to surface water occurs through overland flow, in which contaminants adsorbed to surface soil are eroded and carried to surface water bodies through stormwater in either the total or dissolved phase. Most of the site is either paved or heavily vegetated, and there are no surface water bodies on the site other than stormwater drainage features. Erosion and sediment controls will be implemented during future construction activities to prevent soil from migrating off-site. Based on the factors mentioned above, the potential for migration of contaminants from soil to surface water is minimal.

Soil to Air Migration of contaminants from soil to air can occur from volatilization of contaminants into soil gas and through fugitive dust emissions cause by wind. Under current conditions, the migration of soil contaminants to air is minimal, since most of the site is paved or heavily vegetated. Additionally, the types of contaminants present at the site are not volatile and do not represent a risk from vapor intrusion. Future disturbance of soils during construction activities increases the potential for soil to air migration. Engineering controls such as dust suppression, should be implemented as mitigation measures during future construction.

Contaminant Persistence The tendency for contaminants to persist at the site is controlled by the chemicals’ abilities to withstand chemical change by a variety of processes, including plant uptake, biodegradation, hydrolysis and photolysis. In general, the types of contaminants (metals and SVOCs) identified at the site are not easily degraded under any of these processes.

However, the human health risk posed from the presence of these chemical compounds is controlled by the potential exposure routes to human receptors and the magnitude of concentrations across the site. These factors are discussed in detail in Section 6.

Risk Evaluation

A quantitative human health risk evaluation (HHRE) was performed for site soils in accordance with USEPA’s Risk Assessment Guidance for Superfund (RAGS): Volume 1, Human Health Evaluation Manual (Part A) (USEPA, 1989). The HHRE is summarized in this section.

The HHRE evaluation includes:

1. Data evaluation,

2. Exposure assessment,

3. Toxicity assessment, and

4. Risk characterization and uncertainty analysis.

Data Used in the HHRE The soil samples were collected as described in Section 3.

Exposure Assessment The exposure assessment estimates the magnitude, frequency, duration, and routes of exposure. The exposure assessment includes current and future exposures, and involves three distinct processes: 1) characterizing the exposure setting, 2) identifying exposure pathways, and 3) quantifying exposure.

Exposure Setting Characterization The investigated areas consist of the four parcels as shown on Figure 2. These four parcel are the Navy Annex/FOB2, Parking, Southgate Road Right of Way, and NEX Service Station.

Potential Exposure Pathways Health risks may occur when there is contact with a chemical by a receptor population.

Exposed populations must ingest, inhale, or dermally absorb a chemical of potential concern (COPC) to complete an exposure pathway and potentially experience an adverse health risk. Exposure pathways are determined by the locations of sources, types of release mechanisms, types of contaminants, fate and transport mechanisms, and the locations and activities of the receptors. The potential exposure pathways for the investigated areas is as described below.

6.2.2.1 Current/Future Receptor Scenarios

Under current and future site conditions there is exposure to soils at the ANCSE from future visitors to ANC and to current workers. Of the two receptor types, only the workers would have a chronic exposure; therefore, the only receptor type considered further are adult workers. The potentially complete exposure routes are incidental ingestion, inhalation of particulates (and volatiles if applicable) and dermal absorption to site soils.

There are no complete exposure pathways for site groundwater, so it is not considered further for risk analysis.

Quantifying Exposure Quantifying exposure is conducted in three steps: 1) selection of COPCs, 2) estimation of exposure point concentrations (EPCs), and 3) calculation of chronic daily intakes. The analytical data were evaluated to determine the EPC for COPCs in soil. The RSLs for commercial exposures were used in lieu of intake calculations, specifically, as they have built-in intake equations, exposure pathways, and intake routes (USEPA, 2016). The RSLs are risk-based screening levels derived for a target cancer risk (TR) of 1E-06.

6.2.3.1 Selection of Chemicals of Potential Concern in Soil

Table 6 shows those compounds that had more than a single detection in the soil column and for which there were enough detections to enable ProUCL to calculate an upper confidence limit (UCL). When the UCL values for the compounds in Table 6 were compared to their respective industrial RSL values, only six compounds exceeded its industrial RSL and are thus considered COPCs in soil: arsenic, chromium, benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene and dibenz(a,h)anthracene.

These compounds are highlighted in yellow.

Table 6: Chemicals of Potential Concern in Soil

All Depths Included Industrial RSLs Risk Values Analyte UCL(s) Arsenic 7.641 3 c 2.5E-06

Beryllium 0.729 230 n 0.003 Cadmium 0.319 98 n 0.003

Chromium1 33.42 6.3 c 5.3E-06 Copper 16.3 4700 n 0.003 Lead 51.48 800 Nickel 17.11 2200 n 0.008 Silver 0.443 580 n 0.0008

Sodium 220.7 - - - Zinc 77.41 35000 n 0.002

Mercury 0.071 4.6 n 0.02 DRO 568.3 3300 n 0.2 GRO 9.251 42 n 0.2

Aroclor-1260 0.139 0.99 c 1.4E-07 Acetone 0.0504 67000 n 8.E-07

Bromofluorobenzene 0.0368 - - - Dibromofluoromethane 0.0382 - - -

Acenaphthylene 0.163 - - - Anthracene 4.26 23000 n 0.0002

Benzo(a)anthracene 4.295 2.9 c 1.5E-06 Benzo(a)pyrene 3.297 0.29 c 1.1E-05

Benzo(b)fluoranthene 4.202 2.9 c 1.4E-06 Benzo(g,h,i)perylene 1.974 - - Benzo(k)fluoranthene 1.52 29 c 5.2E-08

Bis(2-ethylhexy…