EPA/ROD/R03-95/205
                                    1995
EPA Superfund
     Record of Decision:
     DEFENSE GENERAL SUPPLY CENTER (DLA)
     EPA ID: VA3971520751
     OU03
     CHESTERFIELD COUNTY, VA
     09/29/1995

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                    FINAL
             RECORD OF DECISION

                    FOR

   NATIONAL GUARD SOURCE AREA
       (OPERABLE UNIT 3)

  DEFENSE GENERAL SUPPLY CENTER
          RICHMOND, VA

CONTRACT NO. DACA 87-94-D0016

        Prepared for:

 U.S. Army Corps of Engineers
      Huntsville Division
    4820 University Square
   Huntsville, AL 35816-1822

         Prepared by:

    Law Environmental, Inc.
 Government Services Division
      114 TownPark Drive
      Kennesaw, GA 30144

        OCTOBER 1995

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              TABLE  OF CONTENTS
                                                                                                Page
       1.0    DECLARATION 	    1-1

       1.1           SITE NAME AND LOCATION  	    1-1

       1.2           STATEMENT OF BASIS AND  PURPOSE  	    1-1

       1.3           ASSESSMENT  OF THE SITE  	    1-1

       1.4           DESCRIPTION OF  THE SELECTED  REMEDY  	    1-1

       1.5           STATUTORY DETERMINATIONS  	    1-4

       2 . 0   DECISION SUMMARY 	    2-1

              2.1           SITE NAME AND LOCATION 	   2-1

              2.2           SITE HISTORY AND ENFORCEMENT ACTIVITY  	   2-6

              2.3           SUMMARY  OF COMMUNITY  PARTICIPATION  	   2-8

              2.4           SCOPE AND ROLE OF OPERABLE UNIT  	   2-9

              2.5           SUMMARY  OF SITE CHARACTERISTICS  	  2-10

              2. 6           SUMMARY  OF SITE RISKS 	  2-18

              2.7           DESCRIPTION OF ALTERNATIVES  	  2-28

                     2.7.1    Alternative 1 - No Action  	   2-33
                     2.7.2    Alternative 2 - Institutional Controls  	   2-33
                     2.7.3    Alternative 4 - Ex-Situ Bioremedition 	   2-35
                     2.7.4    Alternative 5 - Excavation, Off-Site  Disposal  	   2-36

              2.8    COMPARATIVE  ANALYSIS SUMMARY  	    2-38

                     2.8.1    Overall Protection  	   2-38
                     2.8.2    Compliance with ARARs 	   2-39
                     2.8.3    Long-Term Effectiveness and Performance  	   2-40
                     2.8.4    Reduction of Toxicity,  Mobility, or Volume  	   2-40
                     2.8.5    Short-Term Effectiveness 	   2-41
                     2.8.6    Implementability  	   2-41
                     2.8.7    Cost  	   2-41
                     2.8.8    Support Agencies Acceptance  	   2-42
                     2.8.9    Community Acceptance 	   2-42

       2.9    SELECTED REMEDY 	   2-42

                     2.9.1    Cost Summary  	   2-44

       2.10          STATUTORY DETERMINATIONS  	   2-45

                     2.10.1        Protection of Human Health and  the Environment 	  2-45
                     2.10.2        Compliance with ARARs 	  2-46
                     2.10.3        Cost Effectiveness 	  2-46
                     2.10.4        Utilize Permanent  Solutions and Alternative Treatment
                                  Technologies 	  2-47
                     2.10.5        Preference for Treatment That Reduces Toxicity, Mobility,  or
                                  Volume 	  2-47
                     2.10.6        State Acceptance  	  2-47
                     2.10.7        Documentation of  Significant Changes  	  2-48

3.0    RESPONSIVENESS SUMMARY 	   3-1

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                           LIST OF TABLES

       Table                                                                                    Page

       2-1    Constituents Detected in National  Guard Area Soils  	   2-13

       2-2    Constituents Detected in National  Guard Area Upper  Aquifer  	   2-17

       2-3    Constituents of  Concern  Detected in  Surface  and  Subsurface  Soils  	   2-20

       2-4    Risk-Based Action Levels 	   2-21

       2-5    Additional Information on Calculation of Risk for the  Residential Population .   2-26

       2-6   Summary of Estimated  Risk 	   2-27

       2-7   Potential Applicable  or Relevant and  Requirements (ARARs)  	   2-29

                     LIST  OF FIGURES

Fiqure                                                                                     Paqe

2-1           Defense General  Supply Center  and  Surrounding Area  	   2-2

2-2           Location of Underground  Storage Tanks and Areas  of
              Concern in the National  Guard  Area (OU3)  	   2-3

2-3           Soil  Boring Locations  in the National Guard  Area (OU3)  	   2-15

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                     1.0  DECLARATION

              Five-Year Site Review is required.

1.1    SITE NAME AND LOCATION

          National Guard Source Area  (NGA)  - Operable Unit 3, Contaminated Soils

          Defense General Supply Center (DGSC)

          Richmond, Virginia

1.2    STATEMENT OF BASIS AND PURPOSE

1.2.0.1  This decision document presents the selected remedial action for the National Guard
Source Area  (NGA), Operable Unit (OU3) at the Defense General Supply Center  (DGSC) in
Richmond, Virginia, which was chosen in accordance with CERCLA,  as amended by SARA
and, to the extent practicable, the National Oil and Hazardous Substance Pollution Contingency
Plan (NCP).  This decision is based on the administrative record for this site.   The
Commonwealth of Virginia concurs with the selected remedy.

1.3    ASSESSMENT OF THE SITE

1.3.0.1  Actual or threatened releases of hazardous substances from the site, if not addressed
by implementing the response action selected in this ROD, may present an imminent and
substantial endangerment to public health,  welfare, or the environment.

1.4    DESCRIPTION OF THE SELECTED REMEDY

1.4.0.1  This operable unit is the third of thirteen operable units that are currently being
addressed at DGSC.  Operable Unit 3 addresses the contaminated soils at the National Guard
Source Area.  The other operable units, and the portions of the site that they address are as follows:
              OU1 - Open Storage Area
              OU2 - Area 50 Source  Area
              OU4 - Fire Training Source Area
              OU5 - Acid Neutralization Pits Source Area
              OU6 - Area 50/Open Storage Area/National Guard Area Ground Water
              OU7 - Fire Training Area Ground Water
              OU8 - Acid Neutralization Pits Ground Water
              OU9 - Interim Action  for OU6
              OU10 - Building 68
              OU11 - Transitory Shelter 202
              OU12 - Building 112
              OU13 - PAH Area

1.4.0.2 The selected alternative requires that institutional controls,  including access restriction,
property transfer restriction, and preconstruction assessment, be implemented or continued at
the site.  Also, contaminated soils posing human health risks will be excavated and disposed of.
The selected alternative is primarily aimed at reducing or eliminating human contact by reliance
upon physical controls, as well as existing regulatory and administrative requirements, and will
be effective at preventing the inappropriate future usage of the site and exposure to contaminated
soil.  This alternative effectively reduces risk to an acceptable level for the main affected
population, a future residential use, by removal of contaminants, and restricting future use of
the site.  The alternative includes:

                     Maintenance of existing fencing and continued use  of existing security
                     measures  at the facility and NGA site;

                     Implementation of existing deed restrictions and property transfer
                     requirements in accordance with Section 120(h)  of  CERCLA,  42  U.S.C.
                     9620,  and any  regulations  promulgated thereunder;

                     Continued implementation of existing preconstruction assessment
                     procedures to  characterize military construction projects at  the  site,  and
                     policies  which cover routine maintenance or  utility excavations at the

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                     DGSC  facility;

                     Maintenance  of  existing pavement  within the  National  Guard Area;

                     Performance  of  a  follow-up chemical  and biological  monitoring program
                     for No-Name  Creek,  until all  OSA/NGA/Area  50 study  area  remedial
                     actions  are  complete;  and

                     A five-year  review,  to ensure that the  chosen remedy  continues to  provide
                     adeguate protection of human  health  and the  environment.

The excavation and off-site disposal portion of this remedy includes the following elements:

                     Excavation of an  area  of organically contaminated soil within the  alleged
                     former water treatment disposal area containing the highest  levels of
                     carcinogenic-related constituents.   (The area to be excavated is centered
                     around soil  boring  NGASB8,  see Figure 2-3.   Reguired  excavation depths
                     are estimated to  be approximately 2  feet.  The estimated excavation area
                     is approximately  1,100 sguare feet,  and the  estimated volume of material
                     to be removed is  100 cubic yards).

                    Sampling  and  analysis of soils at  the excavation limits  and comparison to
                     risk-based soil action levels for organic  constituents  see (Table  2-3)  or
                     detectable levels (if  detection limits  for standard analytical methods  exceed
                     risk  base levels) to confirm  that contaminated soils  have been removed;

                    Proper storage and testing of  the  excavated soil to  classify the soil
                     material for off-site  disposal in accordance with RCRA  land  disposal
                     reguirements.

                     Transport and disposal of the contaminated soils to a landfill permitted to
                     accept the waste; and

                    Backfilling and  regrading the  excavation using clean borrow material.

1.4.0.3  In addition to taking advantage of existing site characteristics, practices,  and structures
to prevent migration of, or exposure to, any contamination present at the site, this alternative
also prevents future human exposure  to contaminated media at the site.

The selected alternative,  a combination of Proposed Plan Alternatives 2  and 5, is aimed at
reducing the primary carcinogenic threat at the site.   The combination of Alternatives  2 and 5
will provide effective protection of human health and the environment.

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1.5    STATUTORY DETERMINATIONS

1.5.0.1  The selected remedy is protective of human health and the environment, complies with
federal and state requirements that are legally applicable or relevant and appropriate to the
remedial action, and is cost-effective.  This remedy utilizes permanent solutions and alternative
solutions to the maximum extent practicable, and satisfies the statutory preference for remedies
that employ treatment that reduces toxicity, mobility, or volume as a principal element.
Treatment of the low-level threat at the NGA site will be accomplished by removing the
constituents creating the most significant carcinogenic risk.  This remedy utilizes institutional
controls to prevent current and future human exposure to the other contaminated media at the
site.  Because some contamination will not be treated, a review of this ROD will be conducted
within five years after commencement of remedial action to ensure that this remedy continues
to provide adequate protection of human health and the environment.  If it is determined during
a five-year review that the action no longer protects human health and the environment, further
remedial actions will be considered.


Jan B. Reitman                                                Date
Staff Director, Environmental and Safety Policy
Defense Logistics Agency

Thomas C. Voltaggio                                    Date
Director, Hazardous Waste Management Division
Environmental Protection Agency, Region III

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                     2.0  DECISION SUMMARY

2.1    SITE NAME AND LOCATION

         National Guard Area - Operable Unit 3,  Contaminated Soils

         Defense General Supply Center (DGSC)

         Richmond,  Chesterfield County, Virginia

2.1.0.1  The DGSC is located in Chesterfield County, Virginia, approximately 11 miles south
of the city of Richmond  (Figure 2-1).   Operable Unit 3 consists of the National Guard Area
(NGA) soils.  Operable Unit 6 consists of the ground water for the Open Storage Area, Area
50 and National Guard Area, and will be addressed in a separate Record of Decision (ROD).
The NGA is a 15-acre site located on the east-central boundary of DGSC, as shown in Figure
2-2, and east of and adjacent to the former Area 50 landfill.  It has been leased from DGSC by
the Virginia Army National Guard since the 1950s.  The area is generally level and is primarily
covered by concrete, asphalt surfaces, and gravel.  Areas of concern within the NGA include
a former solvent degreasing area, several formerly used and active underground and
aboveground storage tanks, and an alleged water treatment sludge disposal area.  Currently, the
site is used for vehicle maintenance.   Chemicals employed in this process include both
chlorinated and nonchlorinated solvents.

2.1.0.2  The DGSC was originally constructed in 1941 as two separate facilities:  the Richmond
General Depot and Richmond Holding and Reconsignment Point.  In 1962 the installation
became known as the DGSC.

2.1.0.3  The Defense Logistics Agency  (DLA) , an agency of the Department of Defense  (DOD),
provides logistics support to the military services including procurement and supply support,
contract administration and other services.   Since 1942,  the DGSC's mission has been the
managing and furnishing of military general supplies to the Armed Forces and several federal
civilian agencies.   Today DGSC manages more than 300,000 general supply items at a facility
valued at $100 million and encompassing 640 acres.  The DGSC has more than 16 million
sguare feet of covered storage space in 27 large brick warehouses and a million sguare feet of
office space.


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drainage in the NGA area is presently directed towards a storm sewer system that drains
northeastward and discharges into the No-Name Creek at the east boundary of the NGA.  No-
Name Creek flows north-to-south along the eastern edge of the NGA, turns to the east, and
ultimately discharges to the James River.

2.1.0.8  The unconsolidated soils below the NGA have been divided into four formations by the
U.S. Geological Survey.  The Tertiary Eastover Formation is present immediately below the
land surface and consists of up to 25 feet of interlayered beds of sand, silt and clay with
occasional gravel.  The predominantly gray clay and silt of the Tertiary Calvert Formation
underlies the Eastover throughout the area.  The Calvert Formation is typically 11 feet thick.
The Eocene Aquia Formation, approximately 7 feet of gray sand, gravel, and clay underlies the
Calvert Formation.  The Cretaceous Potomac Formation,  which underlies the Aguia Formation,
extends to the bedrock.  The Potomac consists of approximately 40 feet of interbedded sand and
gravel with occasional silty and clayey seams.  Bedrock in the region consists of the Paleozoic
or Precambrian Petersburg Granite.  The Petersburg Granite is overlain with saprolite, a clay-
rich, weathered component of parent bedrock, which retains the features of the granite.

2.1.0.9  Soils and geologic conditions at the NGA area were characterized during the RI at the
site.  An unconfined aguifer is presen within the Eastover Formation.  This aguifer, referred
to as the upper aguifer, would be the first water bearing unit to be impacted by any
contamination originating from the NGA.  Vertical migration of contaminants from the upper
aguifer to the lowest aguifer would be inhibited by the underlying Calvert and Aguia
Formations.  These two formations, which have lower permeabilities than the overlying and
underlying formations, are referred to as the Confining Unit.  Soil and geologic conditions at
the area were characterized during the Remedial Investigation (RI) at the site.  The lower aguifer
is confined by the Calvert and Aguia Formations.

2.1.0.10  Ground-water flow in the upper aguifer is generally towards the northeast.  The
average depth to ground water varies with season but typically ranges from 13 to 16 feet below
ground surface.  The hydraulic gradient has been calculated to range from 0.05 percent to 0.12
percent.  The low hydraulic gradient in the ground water indicates that the potentiometric surface
and ground-water flow direction are susceptible to seasonal changes in recharge, discharge, or
precipitation.  Flow direction of ground water within the lower aguifer is expected to be eastward.

2.1.0.11  Parker Pond and Bellwood Elk Preserve are the two environmental areas near NGA
site in the DGSC.  The Parker Pond is a recreational pond with fish and waterfowl.  It is
stocked with bluegill, largemouth bass, and catfish for recreational fishing.  The Bellwood Elk
Preserve is a 20-acre fenced area supporting eight to ten elk.  The herd is cared for and
monitored by DGSC personnel.

2.2    SITE HISTORY AND ENFORCEMENT ACTIVITIES

2.2.0.1  Past industrial operations at the DGSC have included parachute manufacture and repair,
mess kit and canteen repair, refrigerator repair, material handling, eguipment overhaul, and
engine rebuilding.  Current industrial operations include the refurbishing of steel combat helmets
and compressed gas cylinders using both wet (acid and caustic) and dry  (ball blasting) processes,
and tent and fabric repair.

2.2.0.2  The DGSC motor pool operations include minor vehicle repairs, fluid changes, and
vehicle lubrication.  These activities take place at the motor pool facility located in the southern
portion of the DGSC.  There are several underground gasoline and fuel storage tanks located
throughout the installation.

2.2.0.3  Chemical operations at the DGSC have included storing and shipping flammable, toxic,
corrosive and oxidizer chemicals for DLA.  The majority of the chemicals are stored in
warehouses at the DGSC.  Chemicals stored at the DGSC have also included pesticides and
herbicides for use at DGSC and as part of the chemical stock mission of the DGSC.  The
National Guard Area (NGA) is one area of DGSC.  The Virginia Army National Guard has
leased this property from DGSC since the 1950s.  It is currently used for vehicle maintenance
operations, which includes the use of both chlorinated and nonchlorinated solvents for the
degreasing process.

2.2.0.4  Operable Unit 3 (OU3) consists of soils in the NGA.  Soils of this site are mostly
covered by concrete, asphalt, and gravel.  Previous activities that have occurred in this area
include the use of both underground and aboveground storage tanks for the storage of fuels
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 (gasoline and diesel fuel), oils, and solvents.  Some waste solvents were reportedly disposed of
in the site's storm sewer, or on an unpaved area on the site.  Waste liquids from the NGA have
also been used for dust suppression on local roads.  The former operation of a portable
sandblasting shed in the vicinity of the alleged sludge disposal area has also been reported.
Eight underground storage tank sites exist at the NGA.  Seven have been brought into
conformance with Commonwealth of Virginia regulations by either testing, removal, or
replacement.  One tank  (#7) probably does not exist.  However, DGSC has plans to investigate
this tank within the next year.

2.2.0.5  The primary current activities that occur at the NGA are vehicle maintenance
operations, using both chlorinated and nonchlorinated solvents for degreasing purposes.  Vehicle
maintenance operations occur five days a week and support approximately 50 percent of
Virginia's National Guard.  All currently generated waste oils and solvents are disposed of
through a private contract.  Effluents from the vehicle washracks at this site, which are equipped
with grit traps and off/water separators, are discharged to the sanitary sewer system.

2.2.0.6  Sampling events conducted at the site during the course of RI activities revealed the
presence of certain metals, various polynuclear aromatic hydrocarbons  (PAHs), and some
volatile organic compounds (VOCs).   The upper aquifer is primarily contaminated with volatile
and semi-volatile organics.  Volatile and semi-volatile organics were also detected in the lower
aquifer.  Aquifer contamination at NGA is addressed by this document only to the extent that
it is impacted by soil contamination; ground-water contamination at this site is a component of
Operable Units 6 and 9 and is addressed by separate RODs and proposed plans.

2.2.0.7  The DGSC has implemented a Spill Prevention Control and Countermeasure Plan
 (SPCC) and An Installation Spill Contingency Plan  (ISCP) to aid in the prevention, control, and
remediation of spills at the DGSC.   The SPCC plan identifies procedures and actions that are
to be followed to prevent spills and/or control spills once they occur.  The ISCP presents
guidelines for spill response, including cleanup and disposal of chemicals and contaminated soils.

2.2.0.8  In 1984, the DGSC was recommended for placement on the CERCLA National Priority
List and was promulgated to the NPL in 1987.  This action was a result of a Hazard Ranking
System  (HRS) scoring performed for the DGSC that was based on the conclusions of previous
studies done at the site by the United States Army Environmental Hygiene Agency  (USAEHA).
The DGSC received a hazardous ranking score of 33.35, with 28.5 being the minimum
necessary to be promulgated to the NPL.  In August 1986, the EPA issued a Corrective Action
Permit to DGSC pursuant to the Resource Conservation and Recovery Act  (RCRA), 42 U.S.C.
6901 et seq.  As part of the RCRA activities conducted at the site, Dames & Moore, a
contractor of DGSC, submitted three Remedial Investigation Reports pertaining to sites
investigated at DGSC in 1989.  In September 1990, the DLA, DGSC, EPA, and the
Commonwealth of Virginia entered into a CERCLA Interagency Agreement  (IGA) pursuant to
Section 120 of CERCLA, 42 U.S.C. § 9620, which guides remediation activities.  Since 1990,
DGSC has been completing the Remedial Investigation reports begun by Dames and Moore, and
preparing feasibility studies.  Records of decision have been issued for OU1, OU5 and OU9

2.3    SUMMARY OF COMMUNITY PARTICIPATION

2.3.0.1  On 23 February 1984, the DGSC organized an Interagency Task Force comprised of
state regulatory agencies, U.S. Environmental Protection Agency (EPA), County agencies,
Virginia National Guard, Rayon Park Representatives, and DGSC personnel.  The purpose of
this group was to ensure that actions carried out at the site were done with input and review
from affected parties.

2.3.0.2  DGSC prepared a community relations plan in 1992.  Two public meetings have been
held in support of the records of decision for OU1, OU5, and OU9.   In 1994, the base held a
public information session to provide additional information to the public.  DGSC also sends out
information to a predetermined mailing list on a regular basis.  The community relations effort
meets the requirements of Section 117(a) of the Comprehensive Environmental Response,
Compensation, and Liability Act  (CERCLA) of 1980, as amended by the Superfund
Amendments and Reauthorization Act (SARA) of 1986.

2.3.0.3  The proposed plan and ROD for Operable Unit 3 - National Guard Area were made
available to the public in 1995.  The proposed plan was made available to the public in the
administrative record maintained at the Chesterfield Public Library at the Chesterfield County
Courthouse in Chesterfield, Virginia.  The notice of availability for this document was published
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in the Richmond Times Dispatch, on July 24, 1995.  The public comment period was held
through September 6, 1995.  In addition, a public meeting was held on August 22, 1995.  At
this meeting, representatives from the DLA, EPA, and Commonwealth of Virginia answered
guestions concerning the remedial alternatives evaluated for this site.  A response to the
comments received during this period is included in the Responsiveness Summary,  which is part
of this Record of Decision.  This decision document presents the selected remedial action for
Operable Unit 3 - National Guard Area at the DGSC in Chesterfield County, Virginia, chosen
in accordance with CERCLA, as amended by SARA and, to the extent practicable, the National
Contingency Plan.  The decision for this site is based on the administrative record.

2.4    SCOPE AND ROLE OF OPERABLE UNIT

2.4.0.1  The work at the DGSC has been organized into 13 operable units:

              OU1 -  Open Storage Area
              OU2 -  Area 50 Source Area
              OU4 -  Fire Training Source Area
              OU5 -  Acid Neutralization Pits Source Area
              OU6 -  Area 50/Open Storage Area/National Guard Area Ground Water
              OU7 -  Fire Training Area Ground Water
              OU8 -  Acid Neutralization Pits Ground Water
              OU9 -  Interim Action for OU6
              OU10 - Building 68
              OU11 - Transitory Shelter 202
              OU12 - Building 112
              OU13 - PAH Area

Among these OUs, OU6 and OU9 address the remediation of ground water in the area which
covers the NGA site, OSA site, and Area 50 site.  OU9 is the interim action for OU6.

2.4.0.2  The scope of this action addresses the third operable unit (OU3) at the site, the National
Guard Area  (NGA; Figures 2-1 and 2-2).  OU3 addresses the contaminated soils present at the
NGA.  Ground water at the NGA site will be addressed under Operable Units 6 and 9.  Potential
direct exposure to soils is the main component of risk to human health.  The purpose of this
response is to prevent current or future exposure to the contaminated soil.

2.5    SUMMARY OF SITE CHARACTERISTICS

2.5.0.1  Land use in Chesterfield County in the vicinity of DGSC is primarily single family
residential, intermixed with retail stores and light industry.  The DGSC is the major industry in
the area.  The area to the northeast and east of DGSC has been developed as both single family
and multi-family housing.  Immediately downgradient of the Open Storage Area  (OSA) , Area
50 and the National Guard Area  (NGA) is an undeveloped wooded area approximately 0.25-mile
wide.  An apartment complex is located east of the wooded area.  Rayon Park, a housing
subdivision consisting of 83 houses, is located east of DGSC and south of the wooded area.

2.5.0.2  Municipal water is supplied to the residents of the downgradient apartment complex and
Rayon Park.  All of the off-base residents  (primarily east of the NGA) homes have been served
by the public water supply since June 1987, but some of the homes also have private ground-
water wells.  A residential well survey was performed by Engineering-Science, Inc., in October
of 1992 to determine the locations, number of users in the household,  and types of usage of
residential ground-water wells around the DGSC property.  From the approximate center of the
OSA, NGA, and Area 50 sites, a half-mile radius was extended to determine number of
wells within that area of the DGSC.  A total of 53 wells were identified within the half-mile
radius with 6 identified as being in the Lower Aguifer  (greater than 35 feet) and one being in
the Upper Aguifer (less than 35 feet).  Forty-six  (46) of the wells had no information relating
to the depth of the well.  Of the 53 total wells, four wells are utilized for all the households
water supply needs;  eight wells are used for outside purposes only such as irrigation of lawns,
gardens, etc.; and 34 are not currently in use with most of the owners relying on the public
water supply for their household water needs.  The remaining seven wells had no reported
information regarding current usage of the wells  (ES, 1992).

2.5.0.3  The land surface at NGA has been extensively altered by grading and filling operations.
The topography is essentially flat at the site with limited slope towards the east boundary.  The
maximum difference in the local topographic relief is approximately 12 feet.  Elevations range
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from 120 feet mean sea level (msl) in the west portion of the facility to 108 feet msl on the east
boundary.  Elevations in the NGA range from 112 to 108 feet mean sea level  (msl).   Surface
drainage in the NGA area is presently directed towards a storm sewer system that drains
northeast and discharges into No-Name Creek at the east boundary of NGA.  No-Name
Creek flows north-to-south along the eastern edge of the NGA, turns to the east, and ultimately
discharges to the James River.

2.5.0.4  Several sampling and analysis programs have been performed at the NGA during the
Remedial Investigation and Remedial Investigation Addendum in order to evaluate the magnitude
and extent of contamination.  Soil samples were collected to identify sources of contaminants,
potential pathways of contaminant migration, as well as the magnitude and extent of
contamination.  In addition to soil samples, ground-water samples have also been collected in
order to determine the extent of ground-water contamination below this site.  Further, sediment
and surface-water samples were collected from the unnamed creek in order to characterize
constituents present in these media.

2.5.0.5  The results of the chemical analysis on the soil samples are presented in Table 2-1.
Sample locations are shown in Figure 2-3.

Samples were analyzed for metals volatile organics, and semi-volatile organics.  Samples were
also analyzed for total petroleum hydrocarbons (TPH),  which is a broad analysis (including as
a summation volatile and semi-volatile organic constituents indicative of fuels-related
contamination).   The most freguently detected constituents in the soils at the NGA were metals.
Other constituents detected in soils from this site included volatile and semi-volatile organic
compounds.  Petroleum hydrocarbon contamination at the NGA area is principally limited to the
upper 0 to 5-foot depths, but also present in low concentrations at greater soil depths.  The only
volatile organic compounds detected were acetone, in two soil borings at 1-foot and 3-foot
depths; total xylenes, detected in one boring at 1-foot depth; and methylene chloride.  For the
semi-volatile organics, the majority of constituents were detected only once and at one sample
location in the former sludge disposal area, in a surficial soil sample (acenaphthene, anthracene,
benzo(a)pyrene,  benzo(b)fluoranthene, benzo(g,h,i)perylene, benzo(k)fluoranthene,
dibenz(a,h)anthracene, and indeno(1,2,3-cd)pyrene).  Benzo(a)anthracene was detected at three
sampling locations, at depths of 1 foot and at the surface.  Chrysene was detected at two
sampling locations, at depths of 1 foot and at the surface, respectively.   Fluoranthene was
detected at four sampling locations, at depths of 1 foot in a surficial soils.  Phenanthrene was
detected at four sampling locations, at depths from surface to 4 feet.  Pyrene was detected at
three sampling locations, at depths from surface to 3 feet.  Total petroleum hydrocarbons (TPH)
was detected in NGA soils at concentrations higher than background.  TPH detections in the soil
at NGA were highest in the surficial soils at two sample locations at a depth of 3 feet and 1 foot,
respectively.  Volatiles and semi-volatiles were not analyzed for in these two soil samples with
the highest TPH concentrations.  TPH  (diesel) was detected in concentrations above background
at one sample location, which also had exceedances for volatile and semi-volatile organics.
Petroleum hydrocarbon contamination in the soils was detected at depths up to 14 feet.  The
samples at depths greater than 3 feet had TPH concentrations an order of magnitude less than
the samples taken within the top 3-foot depths.  This indicates that TPH soil contamination is
probably concentrated within the upper 0 to 3-foot depths, but is present at low levels at greater
depths.  The volume of contaminated soil at the NGA is estimated to be 1340 cubic yards.
Based on the levels of the contaminants detected, principal threats, as defined in the NCP,  do
not exist in the NGA area.
-------
                        TABLE 2-1
        CONSTITUENTS  DETECTED IN NATIONAL GUARD AREA SOILS
        Defense General  Supply Center,  National Guard Area
                       Operable Unit 3
                       Richmond,  Virginia
CONSTITUENT

Metals  (mg/kg)

Aluminum
Arsenic
Barium
Beryllium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Nickel
Potassium
Sodium
Vanadium
Zinc
                           FREQUENCY
                         OF  DETECTION
10/10
14/14
10/10
 6/14
10/10
14/14
 6/10
13/14
10/10
14/14
10/10
10/10
  4/4
 9/14
10/10
10/10
 9/10
14/14
Volatile Organics  (• g/kg) :

Acetone                          4/19
Methylene Chloride              19/24
Xylenes  (total)                  1/10
Semi-Volatile Organics  (• g/kg)
Acenaphthene                     1/10
Anthracene                       1/10
Benzo(a)anthracene               3/19
Benzo(a)pyrene                   1/10
                  MAXIMUM DETECTED
                   CONCENTRATION
20,000
   7.5
    74
   1.2
 1,200
 34 JH
    25
 28 JL
76,000
120 JL
   700
   120
  0.04
    27
 2,200
230 JB
    83
    67
                       190
                        31
                       8.9

                       130
                       320
                       990
                       990
                             LOCATION OF
                          MAXIMUM DETECTION
                             DEPTH OF
                             SAMPLE
                                                                            feet
NGA-SB-
NGA-SB-
NGA-SB-
DMS-25
NGA-SB-
NGA-SB-
NGA-SB-
NGA-SB-
NGA-SB-
DMS-30
NGA-SB-
NGA-SB-
DMS-30
NGA-SB-
NGA-SB-
NGA-SB-
NGA-SB-
NGA-SB-
-10B
-8B
-6A

-10A
-6A
-8A
-6A
-8A

-10A
-8A
-8A
-10B
-6A
                          NGA-SB-4
                          NGA-SB-3
                          NGA-SB-3

                          NGA-SB-8A
                          NGA-SB-8A
                          NGA-SB-8A
                          NGA-SB-8A
4
4
0
11.£
0
0
0
4
4
9.5
0
0
9.5
0
0
0
4
0
-------
                                 TABLE 2-1
                     CONSTITUENTS DETECTED  IN NATIONAL GUARD AREA  SOILS
                     Defense General Supply Center, National Guard Area
                                   Operable Unit 3
                                    Richmond, Virginia
CONSTITUENT
                                     FREQUENCY
                                      OF DETECTION
MAXIMUM DETECTED
CONCENTRATION
 LOCATION OF
MAXIMUM DETECTION
DEPTH OF
SAMPLE
 Benzo(b)fluoranthene                 1/10                     1400              NGA-SB-8A
 Benzo(g,h,i)perylene                 1/10                      630              NGA-SB-8A
 Benzo(k)fluoranthene                 1/10                      750              NGA-SB-8A
 Chrysene                             2/23                     1000              NGA-SB-8A
 Dibenz(a,h)anthracene                1/10                      120              NGA-SB-8A
 Fluoranthene                         5/24                     2000              NGA-SB-8A
 Indeno(l,2,3-cd)pyrene               1/10                      670              NGA-SB-8A
 Phenanthrene                         7/24                     1400              NGA-SB-8A
 Pyrene                               6/24                     1800              NGA-SB-8A

 Other Compounds (mg/kg):

 Total Petroleum                     12/21                      420              DMS-49
 Hydrocarbons (TPH)

 Sources:  Dames & Moore,  1989.
          LAW,  1993
          Engineering-Science,  1993

 BDL = Below Detection Limit
 JH = Estimated guantitation possibly biased high based upon QC data
 JL = Estimated guantitation possibly biased low based upon QC data
 JB = Estimated guantitation possibly biased high or false positive based upon QC data
 
-------
2.5.0.6  The primary constituents detected in the upper aquifer ground water at the NGA were
volatile and semi-volatile organics (Table 2-2).  There does not appear to be a correlation
between analytes detected in the soil and ground water at the NGA.  The only analyte detected
in both the NGA soil and Upper Aguifer is methylene chloride, which was attributed to
laboratory contamination of the soil samples and did not exceed the concentrations in the
background soil samples.  In general,  concentrations of constituents in the NGA ground water
were less than or egual to concentrations of the same constituents in the Area 50 ground-water
samples, indicating that the potential source of contamination is located within Area 50.  Nine
compounds, including 1,1-dichloroethane,  chloroform, 1,2-dichloroethane, toluene, carbon
tetrachloride,  1,1-dichloroethene,  vinyl chloride,  bis(2-ethylhexyl)phthalate, and 2-chloroethyl
vinyl ether, were detected at higher concentrations in the NGA ground water than in the Area
50 ground water.  None of these constituents were present in the NGA soils at significant
concentrations.  Therefore, the NGA soils do not appear to be contributing to ground-water
contamination at this site.

2.5.0.7  The primary constituents detected in the lower aguifer were volatile organics.
However, they were detected at considerably lower concentrations than in the upper aguifer.

2.5.0.8  Surface-water samples were collected from various locations of No-Name Creek.
Methylene chloride, toluene, and other volatiles were detected in low levels in some surface-
water samples,  but were not consistently detected in discrete sampling events at the same
locations.  Sediment samples were collected from the unnamed creek during the RI, and while
TPH was detected in all five samples collected,  volatile organics were not.  Semi-volatile
organics were not detected in any sample collected.  The maximum TPH concentration detected
in any sediment sample collected was 430 mg/kg.   Sediment/surface-water toxicity tests
conducted on samples from the unnamed creek show no impacts relative to the control station
on Kingsland Creek, with the exception of an impact to Cladoceran reproduction at an upstream
sample compared to the reference location.  Since the unnamed creek apparently generates as
a function of both ground-water and surface-water discharge from the Open Storage Area, Area
50, and the NGA, contaminants in the creek cannot be directly attributed to soil contamination
at the NGA.  Furthermore, a benthic macroinvertebrate survey was also performed along the
unnamed creek,  with results classifying the benthic populations as moderately impacted.  Since
biodiversity was found to increase downstream,  the lower levels of benthic organisms noted
progressively upstream may be a function of only "point of origin" versus possible
contamination.   The NGA, therefore, probably does not impact the unnamed creek.
-------
                                         TABLE 2-2
                 CONSTITUENTS DETECTED IN NATIONAL GUARD AREA UPPER AQUIFER
                      Defense General Supply Center, Operable Unit 3
                                    Richmond, Virginia
       CONSTITUENT

Volatile Organics

Bromodichloromethane
Carbon tetrachloride
Chlorobenzene
2-Chloroethyl vinyl ether
Chloroform
Dibromochloromethane
1,1 Dichloroethene
1,1 Dichloroethane
1,2 Dichloroethane
1,2 Dichloroethene
trans 1,2 Dichloroethene
1,2-Dichloropropene
Methylene Chloride
Tetrachloroethene
Toluene
1,1,1 Trichloroethane
1,1,2 Trichloroethane
Trichloroethane
Vinyl Chloride
          RANGE OF
DETECTED CONCENTRATIONS

               •g/kg

        BDL - 48
        BDL - 30
        BDL - 230
         BDL - 5
        BDL - 140
        BDL - 39
         BDL - 33
        BDL - 45
        BDL - 50
        BDL - 300
         BDL - 620
        BDL - 240
         BDL - 75
        BDL - 1,100
        BDL - 9.4
        BDL - 23
         BDL - 14
         BDL - 5,500
         BDL - 87
                                                                     LOCATION OF
                                                                    MAXIMUM DETECTION
AEHA-31A
AEHA-28A
AEHA-28A
 AEHA-19A
AEHA-24A
AEHA-14A
 AEHA-18A
AEHA-28A
AEHA-19A
AEHA-24A
 AEHA-28A
AEHA-19A
 AEHA-14A
AEHA-23A
AEHA-21A
AEHA-28A
 AEHA-28A
 AEHA-23A
 AEHA-23A
Semi-Volatile Organics

Bis(2-ethylhexyl)phthalate
1,2 Dichlorobenzene
1,3 Dichlorobenzene
1,4 Dichlorobenzene

Source:  Dames & Moore, 1989

BDL = Below Detection Limit
        BDL - 70
        BDL - 6.3
        BDL - 3.3
        BDL - 14
AEHA-27A
AEHA-20A
AEHA-20A
AEHA-14A
-------
2.5.0.9  There are no promulgated chemical-specific applicable or relevant and appropriate
requirements  (ARARs) for constituents in soils.  The Virginia Department of Environment
Quality  (DEQ) has set an unofficial cleanup level of 100 ppm for TPH at underground storage
tank closures when there is no evidence to suggest that a release has occurred at a site.  At UST
sites where a release has occurred, the VDEQ allows for a site-specific evaluation of potential
TPH exposure and migration.  The 100 ppm TPH guidance value is considered a "to be
considered"  (TBC) requirement, rather than an ARAR.

2.6    SUMMARY OF SITE RISKS

2.6.0.1  The baseline risk assessment provides the basis for taking action and indicates the
exposure pathways that need to be addressed by the remedial action.  It serves as the baseline
indicating what risks could exist if no action were taken at the site.  This section of the ROD
reports the results of the baseline risk assessment conducted for this site.

2.6.0.2  A baseline risk assessment has been conducted for the Area 50, OSA, and NGA as
documented in the RI Report and revised in the Remedial Investigation Report Addendum for
Area 50, Open Storage Area and National Guard Area (RI Addendum).   The objective of a
baseline risk assessment is to provide the framework for developing risk information necessary
to assist in the risk management decision-making process at investigation sites.  The baseline risk
assessment evaluates the potential health impact of the contaminants detected in soil, ground
water, surface water, and sediments on the exposed and potentially exposed populations if no
action is taken to remedy conditions at the site.  The RI Addendum baseline risk assessment
treats the media for Area 50, OSA, and NGA as one operable unit and does not separate the soil
results by site.  This baseline risk assessment summary from the RI Addendum includes only
the results pertinent to the National Guard Source Area (i.e., contaminated soils).

2.6.0.3  Table 2-3 presents a summary of information relative to constituents of concern within
soils at the NGA.  Note that the number of constituents of concern shown on Table 2-3 is
reduced from the total number of constituents encountered at the site.  This reduction is done
to create a more manageable list of constituents, and is performed by considering the toxicity
and frequency of occurrence for each constituent.  For each constituent, the range of reported
values is compared to background, the EPA Region III screening concentration, and a site-
specific risk-based cleanup level developed for the potential future residential use.  The boxed
values on Table 2-3 represent the chosen cleanup level, i.e., the concentration to which cleanup
should occur.  This chosen cleanup level is either the lowest of the calculated noncarcinogenic
and carcinogenic risk-based soil cleanup levels or the background concentration.  The differences
between the EPA Region III RBCs and the calculated risk-based soil cleanup levels can be
attributed to the inclusion of the dermal route of exposure in the risk-based soil cleanup level
calculations.  In addition, as noted in the table, the RBCs are adjusted to represent a 0.1 hazard
index, whereas the calculated risk-based soil cleanup levels represent a hazard index of 1.  The
bolded and italicized numbers on Table 2-3 indicate constituents which exceed cleanup levels.
As may be seen, two metals  (beryllium and manganese)  and six semi-volatile constituents exceed
cleanup levels based on the potential future residential use.  Table 2-4 provides additional
information concerning the calculation of the risk-based soil action levels.

2.6.0.4  A potential data limitation exists for surface soil at the NGA.  The data collected at the
former sludge disposal area and the former solvent degreasing area represents only a small
portion of the site and potentially the worst case concentrations of constituents.  However,
because these are the only surficial soil data available,  they have been used to characterize
exposure for the entire NGA.  The use of these data may tend to overestimate the risk for this
area.
-------
PARAMETER

METALS  (Total) ,  ing/kg:
 Aluminum
 Barium
 Beryllium
 Copper
 Lead
 Manganese
 Vanadium

 SEMI - VOLATILES, mg/kg:
 Benzo(a)anthracene
 Benzo(a)pyrene
 Benzo(b)fluoranthene
 Benzo(g,h,i)perlyene
 Benzo(k)fluoranthene
 Chrysene
 Dibenz(a,h)anthracene
 Fluoranthene
 Indeno(1,2,3-cd)pyrene
 Phenanthrene
 Pyrene

 VOLATILES, mg/kg:
 Methylene Chloride

 OTHERS, mg/kg:
 Petroleum Hydrocarbons  (Diesel)
  FREQUENCY
      OF
DETECTION  (a)
    10/10
    10/10
     5/10
    10/10
    10/10
    10/10
     9/10
     3/19
     1/19
     1/19
     1/19
     1/19
     2/19
     1/19
     4/19
     1/19
     5/19
     5/19
     6/19
     2/9
                     TABLE 2-3
CONSTITUENTS OF CONCERN DETECTED IN SURFACE AND SUBSURFACE SOILS
                  Residential End-Use
  Defense General Supply Center, National Guard Area
            Richmond, Virginia
                                                               REGION III RISK-
  RANGE  OF                     MAXIMUM                     BASED SCREENING
       REPORTED                   BACKGROUND                   CONCENTRATION  (c)
         VALUES                  CONCENTRATION  (b)
                                                                                                                                  Residential Soil
7,500
10
0.35
3.1 JL
16 JL
24
23
- 20,000
- 74
- 1.1
- 28 JL
- 120 JL
- 120
- 83
                                   11,400
                                     22
                                    0.51
                                    21.9
                                     57
                                     66
                                     44
0.11 JH - 0.99
        0.99
        1.4
        0.63
        0.75
      0.19 - 1
        0.12
      0.19 - 2
        0.67
    0.076 - 1.4
     0.17 - 1.8
    0.014 - 0.019
       35 - 140
                                                                       23,000
                                                                         550
                                                                         0.15
                                                                         290
                                                                       500  (d)
                                                                          39
                                                                          55
                                                                        0.88
                                                                        0.088
                                                                        0.88
                                                                        0.088
                                                                         310
                                                                        0.88

                                                                         230
                                                                       85
                                                                                          RISK-BASED
                                                                                     SOIL ACTION
                                                                                              LEVEL
                                                                                              Residential
151,000
 1,590
 0.107
 2,770

 45.2
  364
0.0425
0.00428
0.0425

 0.425
 4.25
0.00425
  120
0.00425

  89.9
                                                                                                  4.13
 Indicates the Chosen Soil Action Level, i.e., the concentration to which  clean up  should  occur.   This  chosen  soil  action level  is  either the lowest of the calculated
noncarcinogenic and carcinogenic Risk - Based Soil Action Levels or the Background  Concentration.
 Italic numbers indicate an exceedance of the Region III Risk-Based Screening Concentrations.
 Bolded numbers indicate an exceedance of the Chosen Soil Action Level, i.e, either the  calculated Risk-Based  Soil  Action Level  or  the  Maximum Background Concentration.
 Bolded and Italic numbers indicate an exceedance of both the Region  III Risk-Based Screening Concentration  and  the Chosen Soil  Action  Level.
                                                                                                       SB-3 (0.5-2.5 ft.), SB-DUP
(a)  Number of samples in which chemical was positively detected/the number of samples available.
(b)  Maximum values from shallowest soil borings, Dames and Moore sample DMW-10A-3  (10 ft.), Engineering Science  samples  -  SB-1  (0.5-2.5  ft.)
     (duplicate or SB-3  (0.5-2.5 ft.)).
(c)  EPA Region III Risk-Based Concentration Table, First Quarter, January 7, 1994.  Values are for residential soil.   (Risk-Based  Screening  Concentrations  adjusted to
     represent a 0.1 hazard index, as appropriate).
(d)  OSWER Directive #9355.4-02, Interim Guidance on Establishing Soil Lead Cleanup Levels at Superfund Sites, USEPA Office of Solid Waste  and  Emergency  Response,  1989.
       JH Estimated value:   possibly biased high
 JL Estimated value:  possibly biased low
-------
                                                                                                 TABLE 2-4
                                                                            RISK - BASED SOIL ACTION  LEVELS  - ON  -  SITE  RESIDENT
                                                                                             NATIONAL GUARD AREA
                                                                             Defense General Supply Caser, Operable Unit 3
                                                                                             Richmond, Virginia
                                                                                                                                                                                                   Pathway-Specific Soil Action Levels

                                                                    Cancer Slope Factor  (*)                      Adult Noncare, Action  Level  (mg/kg)        Child Noncare,  Action Level  (mg/kg)    Carcin.  Action Level (mg/kg)               (All  Pathways)  mg/kg
                                                 Point Cone.          Cond.                                 (mg/kg/day)     (mg/kg/day)-1                              (Individual Chem. Risk = 1.0)                      (Individual  Chem.  Risk = 1.0)
(Individual Chem. Risk = 1x10-8)           Adult          Child
      Chemical                         (mg/kg)           (mg/kg)      Oral                Dermal(d)  Inhalation(c)    Oral    Dermal(d)   Inhalation(c)    WOE         Ingest       Inhal.      Dermal      Ingest     Inhal.     Dermal         Ingest.     Inhal.
Dermal       Noncare.         Noncare.    Carcin.

          Metals:
          Aluminum                     1.61E+04  2.00E+04            2.90E+00  1.45E-01  ND          ND           ND               ND                         2.12E+06       - -       2.05E+06           2.27E+05       - -       4.52E+05              - -
         - -            1.03E+06      1.51E+05     - -
          Barium                       6.39E+01  7.40E+01  7.00E-02  3.50E-03 1.43E-04    ND           ND               ND                         5.11E+04      1.32E+04    4.89E+04           5.47E+03   2.83E+03      1.09E+04      - -            - -
              8.65E+05     1.59E+05     - -
          Beryllium                              6.42E-01  1.10E+00  5.00E-03  2.50E-04  ND        4.30E+00  8.60E+01     8.40E+00         B2        3.65E+03       -  -        3.49E+03         3.91E+02       - -       7.79E+02      1.49E-01       2.57E+01
1.78E+03     2.60E+02    1.07E-01
          Copper                       2.02E+01  2.80E+01  3.71E-02  2.08E-02  ND         ND           ND               ND                         2.71E+04       -  -   2.91E+05                2.90E+03      - -        6.48E+04          -  -             -  -
    2.48E+04     2.77E+03     - -
          Lead                                   7.03E+00  1.20E+02     ND                  ND

                                                 1.10E+02  1.20E+02  5.00E-03  2.00E-04 1.43E-05

                                       6.60E+01  8.30E+01  7.00E-03  3.50E-04  ND         ND


          Semi-Volatiles:
          Benzo(a)anthracene           1.25E-01  9.90E-01      ND                   ND             ND    7.30E-01   7.30E-01      6.10E-01            B2
4.46E-02       - -          - -       4.25E-02
          Benzo(a)pyrene                         2.94E-01  9.90E-01     ND                  ND              ND        7.30E+00  7.30E+00      6.10E+00
8.78E-02    3.53E+01  4.46E-03        - -           -  -      4.25E-03
          Benzo(b)fluoranthene                   2.62E-01  1.40E+00     ND                  ND              ND        7.30E+01  7.30E-01      6.10E-01
3.53E+02  4.46E-02       - -          - -       4.25E-02
          Benzo(g,h,i)perylene                   2.19E-01  6.30E-01     ND                  ND              ND           ND          ND              ND

          Benzo(k)fluoranthene                   2.39E-01  7.50E-01     ND                  ND              ND        7.30E-02  7.30E-02      6.10E-02
8.78E+00    3.53E+03  4.46E-01        - -           -  -      4.25E-01
          Chrysene                           1.35E-01     l.OOE+00     ND                  ND              ND        7.30E-03  7.30E-03      6.10E-03
8.78E+01    3.53E+04  4.46E+00        - -           -  -      4.25E+00
          Dibenz(a,h)anthracene        1.20E-01  1.20E-01      ND                   ND             ND        7.30E+00  7.30E+00      6.10E+00
3.53E+01  4.46E-03       - -          - -       4.25E-03
          Fluoranthene                           2.39E-01  2.00E-01  4.00E-02  4.00E-02           ND           ND          ND              ND
             - -            -  -              - -            5.48E+02           1.20E+02         - -
          Indeno(l,2,3-cd)pyrene       2.48E-01  6.70E-01      ND                   ND             ND    7.30E-01   7.30E-01      6.10E-01            B2
- -          - -          - -       4.25E-02
          Phenanthrene                           2.18E-01  1.40E+00     ND                  ND              ND           ND          ND               ND
8.78E-01    3.53E+02  4.46e-02        - -           -  -       - -
          Pyrene                                 2.71E-01  1.80E+00  3.00E-02  3.00E.02          ND            ND          ND
- -        - -        4.11E+02      8.99E+01      - -

          Volatiles:
          Methylene  Chloride           1.20E-02  1.90E-02  6.00E-02  6.00E-02     8.57E-01    7.50E-05  7.50E-03      1.65E-03  B2        4.38E+04       7.94E+07    8.39E+02             4.69E+03   1.70E+07   1.87E+02        8.55E+01     1.31E+05  4.34E+00
8.22E+02     1.80E+02    4.13E+00


                                                 1.40E+02  1.40E+02     ND                  ND              ND           ND      ND                  ND                           - -          -  -          -  -                  - -        - -          - -


          (a)  Source  for RfDs  and CSFs:   USEPA's IRIS,  1994,  and HEAST,  1993                                                                                                                       PATHWAY -  SPECIFIC INTAKES:
          (b)  Dermal  RfD =  Oral RfD* Percentage Absorbed                                                                                                                                           Ingestion  of Incarcinogen:    1.37E-06 day -1
          (c)  Inhalation "RfD" represents inhaled  dose  corresponding to  RfC where  "RfD = (RfC*20 m3/day)/7Okg.                                                                                                                  1.28E-05 day -1
          (d)  Dermal  CSF =  Oral Slope Factor/Percentage Absorbed                                                                                                                                                    Carcinogen:  1.56E-06 day -1
          (e)  Combined Soil Action Level (Carcinogens)  = 1E-06/[(Intake  Factor(ing)  * CSF(oral))  + (Intake Factor(inh) * CSF(inh)) + (Intake  Factor(der)  *  CSF(der))]
              Combined Soil Action Level (Noncarcinogens) = l/[(Intake Factor(ing)/RfD(oral))  + (Intake Factor(inh)/ RfD(inh)) +  (Intake Factor(der)/  RfD(der))]            Inhalation of Incarcinogen:     1.08E-08  day  -1              (Adult)

                    (Child)
          -  -  Soil Action Levels could not be calculated for  the pathway or chemical due to  a  lack of toxicity information  or toxicity values.                                                 Carcinogen:  4.64E-09  day  -1
          ND - Not determined; data not available
          WOE  - Weight of Evidence; USEPA carcinogen  classification according  to the weight  of evidence from epidemeologic  and animal studies.                               Dermal  Contact  with Soils    Manganese
                   All  Other  Compounds
                                                                                                                                                                                                                          Noncarcinogen:    7.16E-07
                               7.16E-08 day  -1  (Adult)      7.16E-05 day -1 (Adult)

                                         3.21E-07 day -1 (Child)       3.21E-04 day -1  (Child)

                                         3.07E-08 day -1              3.07E-05 day -1
-------
2.6.0.5  A complete exposure pathway consists of a source, a release mechanism, an
environmental transport route leading to an exposure point, a receptor, and an exposure route.
There are four potential exposure pathways at the site.  There are exposure to soils (including
airborne particulates),  surface water, sediments, and ground water under present site conditions
or under anticipated future site use.

2.6.0.6  Under the current conditions, which are light industrial basewide, and vehicle
maintenance for the NGA area, the most likely exposure to soil at the site is for on-site workers
and residents.  Potential exposure routes are through dermal contact with contaminated soils,
incidental ingestion of soils through hand to mouth contact, and inhalation of contaminated dust
particles.  Based on current site use, on-site workers, utility workers, construction workers, and
possible future-use residents are the receptors most likely engaging in activities which have the
potential to lead to exposure to soils.

2.6.0.7  Potential sources of contamination also include the stream sediments and surface water
in No-Name creek, on and off the NGA site.  No-Name Creek is a small intermittent stream,
and use of the surface water as potable water is not expected.  However, given the proximity
of the creek to off-site resident housing and unlimited access to the creek, public wading by
children and adults is a plausible scenario for residential exposure to No-Name Creek sediments
and/or surface water.  Future land use in the areas adjacent to the base is expected to remain
residential.

2.6.0.8  On-site exposure to ground water beneath the NGA site is not expected.  There are
currently no drinking water supplies on the DGSC facility utilizing ground water.  Drinking
water for DGSC is received through the county water supply.  Off-site residents have the
potential to come into contact with contaminated ground water through the use of private wells
for drinking water and other uses (bathing, irrigation of gardens, etc.).   However, ground water
issues will be addressed in OU6/OU9.  In general, the future land use is expected to remain
unchanged from its present use.

2.6.0.9  A transfer of property, owned by DGSC, must be in accordance with section 120 (h)
of CERCLA, 42 USC §9620 (h) and any regulations pursuant to Section 120 (h) and Section 40
of Code of Federal Regulations  (CFR) Part 373.  These regulations require the name, date, and
quantity  (concentration) of any hazardous wastes that have been stored one year or more,
released, or disposed of on the site be identified and reported prior to any property transfers.
Therefore, potential future exposure related to residential use would be evaluated and
at the time of such property transfer.  DGSC currently has no plans to sell the subject property.
However, although no future residential exposure is thought likely to occur, future residential
exposure is considered in the baseline risk assessment, and in the subsequent calculation of soil
cleanup levels used in this ROD.

2.6.0.10  DGSC has certain precautions in place to prevent exposure to contaminated subsurface
soil.  Any military construction projects that take place on the facility require a preliminary
assessment screening  (PEAS) to be performed by facility environmental staff prior to any
intrusive activities at a site.  The original plan to characterize all DLA sites and prepare a
detailed map of each category, as outlined in the DLA-W Policy Memorandum dated December
27, 1989, has not been implemented.   However, the current procedure of conducting a PEAS,
and other procedures discussed in the DLA-W Policy Memorandum such as a review of aerial
photographs,  soil gas analysis and soil borings, and precautionary instructions to the construction
contractor to contact the facility environmental and safety group in the event of unusual
situations during construction, would serve to protect human health during construction activities.

2.6.0.11  The toxicity assessment is an integral part of the risk evaluation process.  Quantitative
reference values describing the toxicity of the constituents of concern are evaluated.   Toxicity
values such as the Reference Dose (RfD) and the Carcinogen Slope Factor (CSF) are based
primarily on human and animal studies with supportive evidence from pharmacokinetics,
mutagenicity, and chemical structure studies.

2.6.0.12  Slope factors (SFs) have been developed by EPA's Carcinogenic Assessment Group
for estimating excess lifetime cancer risk associated with exposure to potentially carcinogenic
contaminant(s) of concern.  SFs, which are expressed in units of mg/kg-day-1, are multiplied by
the estimated intake of a potential carcinogen, in mg/kg-day, to provide an upper-bound estimate
of the excess lifetime cancer risk associated with exposure at that intake level.  The term "upper
bound" reflects the conservative estimate of the risk calculated from the SF.  Use of this
approach makes underestimation of the actual cancer risk highly unlikely.   Slope factors are
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derived from the results of human epidemiological studies or chronic animal bioassays to which
animal-to-human extrapolation and uncertainty factors have been applied (e.g., to account for
the use of animal data to predict effects on humans).

2.6.0.13  Reference doses (RfDs) have been developed by the EPA for indicating the potential
for adverse health effects from exposure to contaminant(s) of concern exhibiting noncarcinogenic
effects.  RfDs, which are expressed in units of mg/kg-day, are estimated of lifetime daily
exposure levels for humans,  including sensitive individuals.  Estimated intakes of contaminant(s)
of concern from environmental media (e.g., the amount of a contaminant(s)  of concern ingested
from contaminated-drinking water) can be compared to the RfD.  RfDs are derived from human
epidemiological studies or animal studies to which uncertainty factors have been applied (e.g.,
to account for the use of animal data to predict effects on humans).

2.6.0.14  Risks from potential carcinogens are estimated as probabilities of cancer as a result
of exposure to chemicals from the site.  The risks from each pathway (dermal contact, inhalation
and ingestion)  can be summed to find the combined risk for the receptor.  The combined risk
of the constituents of concern in soil for the on-site utility worker was estimated to be 5 x 10-6,
which is within the USEPA's Target Risk Range of 1 x 10-4 to 1 x 10-6.   The combined risk for
the future on-site residential exposure to soil was estimated to be 1 X 10-4, which is at the high
end of the Target Risk Range.  Additional information on the calculation of risk for the
residential population is summarized on Table 2-5.

2.6.0.15  Noncarcinogenic effects are characterized by comparing the estimated chemical intakes
to the appropriate reference dose (RfD) value.  The ratio of the chronic RfD to the chronic daily
intake for a specific chemical is termed the hazard quotient.  The sum of the individual chemical
hazard quotients is the hazard index for that pathway.  A hazard quotient or index greater than
one indicates that the threshold for response for that chemical or pathway has been exceeded.
The total combined hazard index for the soil pathways (dermal contact,  inhalation and incidental
ingestion) for the on-site utility worker was estimated to be 0.02.  The total combined soil
pathway risks for the future on-site residential adult and child exposures to soil were 0.5 and 2.5
respectively.  The hazard index for the on-site residential child is the only hazard index that
exceeds the USEPA's threshold value of one.

2.6.0.16  Estimated risks for each potentially exposed receptor group are summarized in Table
2-6.  As may be seen, the potential use of the site by future residents represents the highest risk,
with the noncarcinogenic risk exceeding its target range and the carcinogenic risk being at the
unacceptable end of the target range.   Noncarcinogenic risks were not exceeded for any of the
other receptor groups.  Carcinogenic risks were within the target range for on-site workers and
utility workers.  However, it should be noted that conservative assumptions are made in the
calculation of risks which may lead to an overestimation of actual risk.  For example, the on-site
worker scenario does not take into account the presence of an asphalt or concrete cover over the
site which would minimize the potential human exposure to soils, and therefore, reduce the
potential risk.  Benzo(a)pyrene is the main contributor to potential risk to on-site workers at the
NGA.  However,  benzo(a)pyrene was detected in only one of 19 samples, the sample being
taken from a currently unused area.   The risk assessment makes the conservative assumption that
benzo(a)pyrene is present at similar concentrations across the whole site, which will overstate
the risk due to this chemical.  Due to these conservative assumptions,  risks to on-site and utility
workers are considered borderline at the NGA.
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                            TABLE  2-5

                     ADDITIONAL INFORMATION ON
          CALCULATION OF RISK FOR THE RESIDENTIAL POPULATION
                      (Potential Future Use)
               Defense General  Supply Center, Operable Unit 3
                         Richmond,  Virginia

CARCINOGENIC RISK                               ESTIMATED EXCESS CANCER RISK
On-Site Residential Adult:

       Incidental ingestion of soils                       IE-OS

       Inhalation of fugitive dust                         4E-08

     Dermal contact with  soils                            1E-04

Total risk for on-site residential adult  (NGA):           1E-04

NON-CARCINOGENIC RISK                           ESTIMATED HAZARD INDEX

On-Site Residential Adult:

       Incidental ingestion of soils                       0.05

       Inhalation of fugitive dust                         0.02

       Dermal contact with soils                           0.4

Total risk for on-site residential adult  (NGA):           0.5

On-Site Residential Child

       Incidental ingestion of soils                       0.5

       Inhalation of fugitive dust                         0.1

       Dermal contact with soils                           1.9

Total risk for on-site residential child  (NGA):           2.5
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                             TABLE 2-6

                       SUMMARY OF ESTIMATED RISK
          Defense General Supply Center, Operable Unit 3
                     Richmond, Virginia

                                            ESTIMATED                 ESTIMATED
POTENTIAL RECEPTORS                CARCINOGENIC RISK      NONCARCINOGENIC  RISK

On-site workers                              4 x 10-5                   0.18

Utility workers                              5 x 10-6                   0.02

Construction workers                         8 x 10-7                   0.27

Residents (potential future use)             1 x 10-4                   2.5*

Target risk range                            1 x 10-4 to  1 x  10-6        1.0

* Child exposure
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2.6.0.17  Ecological risks posed by the site to the environment were considered very slight
during the RI.   This was mainly because of the low levels of contaminants present.  The primary
exposure pathway which was considered in the environmental pathway was surface run-off to
the stream near the site.  However, surface-water and sediment toxicity testing in the adjacent
No-Name Creek did not indicate impact to the stream,  and the benthic macroinvertebrates also
indicated no significant impact to species diversity or abundance.  Also, in assessing the
environmental transport routes present at the site, no critical habitats or endangered species were
identified that would be affected.  Considering the limited impact to the creek and the limited
contamination at the site, it is difficult to conclude that the site poses any ecological risk.

2.6.0.18  Actual or threatened releases of hazardous substances from the site, if not addressed
by implementing the response action selected in this ROD, may present an imminent and
substantial endangerment to public health, welfare, or the environment.

2.7    DESCRIPTION OF ALTERNATIVES

2.7.0.1  CERCLA reguires that each selected site remedy be protective of human health and the
environment, comply with ARARs, utilize permanent solutions and alternative treatment
technologies or resource recovery technologies to the maximum extent practicable, and be cost
effective.  ARARs identified for OU3 are shown in Table 2-7.

2.7.0.2  During the Focused Feasibility studies (Focused Feasibility Study Report for OU3 -
National Guard Source Area, Law Environmental, September 1994) for the NGA site, seven
remedial action alternatives were initially identified.  Through screening, four out of seven
remedial action alternatives were selected for detailed analysis.  These four alternatives are
described in the following paragraphs.  For easy reference, the same numbers used in the FS
report are assigned to these alternatives.  The four alternatives are as follows:

             Alternative 1 (No Action)
             Alternative 2 (Institutional Control)
             Alternative 4 (Ex-Situ Bioremediation)
             Alternative 5 (Excavation,  Off-Site  Disposal)
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                                          TABLE 2-7
             APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS  (ARARs)
                          AND TO BE CONSIDERED  (TBCs) REQUIREMENTS
                                 NATIONAL GUARD SOURCE AREA
                                      OPERABLE UNIT 3
 TYPE OF ARAR

Chemical-Specific


Location-Specific
                                            ARARs
None identified
                                                                                         TBCs
USEPA Region III Risk-Based Screening Concentrations
      Risk-based Action Levels for Constituents in Soil
           Endangered Species Act of 1973                     Protection of Wetlands
      (16 USC 1531-1544)                                (Executive Order 11990)

           VA Endangered Species Act
      (Code of VA §29.1-563 et.  seg. )

      Fish and Wildlife Coordination Act Reguirements
      (33 CFR 320-330;  40 CFR 6.302)

      VA Wetlands Act Reguirements
      (Code of VA Title 62.1,  Chapter 2.1)

      VA Wetlands Regulations
      (VR 450-01-00510)

      Virginia State Water Control Law
      (Code of VA 62.1-44.2 et.  seg.)

      Virginia State Water Control Board Regulations entitled "Water Quality
      Standards" (VR 680-21-00)

      VA Standards for Surface Water
      (VR 680-21-01.14)

      Stormwater Discharge Reguirements National Pollutant Discharge
      Elimination System (CWA 40 CFR 122)

      Virginia Pollutant Discharge Elimination System (VPDES)  and Virginia
      Pollution Abatement (VPA)  Permit Program (VR 680-14-01)

      VA Water Protection Permit Regulations
      (VR 680-15-02)

      VA Stormwater Management Regulations
      (VR 215-02-00)

      VA Stormwater Management Act
      (Code of VA §10.1-603.1 et.  seg.)

      Floodplain Management
      (Executive Order 11988)
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       TYPE OF ARAR
                                                       TABLE 2-7

                            POTENTIAL APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS (ARARs)
                                                AND TO BE CONSIDERED  (TBCs) REQUIREMENTS
                                                NATIONAL GUARD  SOURCE AREA
                                                       OPERABLE UNIT 3

                                                                        ARARs
                                         Chesapeake Bay Preservation Act
                                          (Code of VA §10.1-200 et.  seq.)

                                         Chesapeake Bay Preservation Area Designation  and Management
                                         Regulations  (CBPA Regulations)  (VP,  173-02-01)

Action-Specific

No Action                                None identified

 General Requirements  (all actions)             Hazardous Waste Operations and Emergency Response

                                   (OSHA 29  CFR 1910.120)

                                         Occupational Safety  and Health Standards  for  Air Contaminants
                                          (29 CFR 1910.1000)

                                         Recordkeeping and Reporting Requirements
                                          (OSHA 29 CFR 1904)

                                         National Ambient Air Quality  Standards  (NAAQs)
                                          (CAA 40 CFR Part 50)
Institutional Controls
 None identified
Containment/Capping
In-Situ Bioremediation
RCRA-Closure Requirements
 (40 CFR 264 Subpart G)

 Closure and Post-Closure Requirements
 (VHWMR § 10.6)

 VA Regulations  for the Control and Abatement of Air Pollution
 (VR 120-01-01;  VR Rules 4-2,  4-3,  5-3)

 RCRA-Organic Air Emissions Standards for Process Vents
 (40 CFR 264-Subpart AA)
                                                                                                                                   TBCs
                                                                            None  identified

                                                                                None identified
RCRA-Closure Requirements
    (40  CFR  264  Subpart  G)

       Closure and Post-Closure Requirements
    (VHWMR §10.6)

None identified
ACGIH Threshold Limit Values  (TLVs)

       OSHA Permissible Exposure Limits  (PELs)
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TYPE OF ARAR

Action-Specific  (Cont.;
                                                              TABLE 2-7

                            POTENTIAL APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS (ARARs)
                                         AND TO BE  CONSIDERED  (TBCs)  REQUIREMENTS
                                                    NATIONAL GUARD SOURCE AREA
                                                       OPERABLE UNIT  3

                                                                     ARARs
Excavation and Off-Site Disposal
    (General Requirements applicable
   to all identified process options)
                                                 VA Solid Waste Management Regulations
                                                         (VR 672-20-10)

                                                 VA Hazardous Waste Management  Regulations
                                                  (VR  672-10-1)

                                                 Standards Applicable to  Generators  of  Hazardous  Waste
                                                  (40  CFR 262)

                                                 Standards Applicable to  Transporters of  Hazardous  Waste
                                                  (40  CFR 263)

                                                 Standards for Owners and Operation  of  Hazardous  Waste Treatment,
                                                 Storage, and Disposal Facilities  (RCRA 40  CFR 264)

                                                 RCRA Land Disposal Restrictions
                                                   (40 CFR 268)

                                                 RCRA Closure and  Post-Closure
                                                  (40  CFR 264)

                                                 Closure and Post-Closure
                                                  (VHWMR  §10.6)

                                                 DOT  Rules for Transportation of Hazardous  Materials
                                                  (49  CFR 107)

                                                 RCRA Manifesting, Recordkeeping,  and Reporting Requirements
                                                  (40  CFR 264)

                                                 RCRA Standards for Identification and  Listing of Hazardous Waste
                                                  (40  CFR 261)

                                                 VA Regulations for the Control and  Abatement  of  Air  Pollution
                                                  (VR  120-01-01; VR Rules  4-2, 4-3, 5-3)

                                                 Deposition of Excavated  Soils
                                                  (40  CFR 267 Subpart  C)
                TBCs



  ACGIH Threshold Limit Values  (TLVs)

OSHA Permissible Exposure Limits  (PELs)
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                                                                                            TABLE  2-7

                                                       POTENTIAL APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS  (ARARs)
                                                                   AND TO BE CONSIDERED (TBCs) REQUIREMENTS
                                                                           NATIONAL GUARD SOURCE AREA
                                                                                      OPERABLE UNIT 3
TYPE OF ARAR

Action-Specific  (Cont.)

Excavation and Off-Site Disposal
Incineration/Thermal Treatment
Ex-Situ Soil Washing
Ex-Situ Bioremediation
Ex-Situ Solidification
                                                                                              ARARs
 VA Erosion and Sediment Control Regulations
  (VR 625-02-0)

 Releases from Solid Waste Management Units
        (40 CFR 268)

        National Ambient Air Quality Standards (NAAQs)
 (CAA 40 CFR Part 50)

 RCRA Incinerator Regulations
 (40 CFR 264)

Occupational Safety and Health Standards for Air Contaminants
 (29 CFR 268)

 RCRA Standards for Identification and Listing of Hazardous Waste
 (40 CFR 261)

General Pre-treatment Regulations for Existing and New Sources
 of Pollution for Publicly Owned Treatment Works (POTW)
 (40 CFR Parts 401 and 403)

 National Emission Standards for Hazardous Air Pollutants  (NESHAP)  (40
 CFR 61)

 RCRA-Organic Air Emission Standards for Process Vents
 (40 CFR 264 Subpart G)

 National Emission Standards for Hazardous Air Pollutants  (NESHAP)  (40
CFR 61)

RCRA-Organic Air Emission Standards for Process Vents
 (40 CFR 264 Subpart G)
                                                                                                                                             TBCs
              None identified
None identified
       None identified
       None identified
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2.7.1         Alternative 1 - No Action

2.7.1.1  The cost estimate for Alternative 1 is as follows:

                     Capital  Cost:                 $0
                     Annual 0 &  M Cost:            $0
                     Present  Worth  Cost:           $0
                     Months to Implement:          N/A

2.7.1.2  The Superfund program requires that the "No Action" alternative be evaluated at every
site to establish a baseline for comparison of other developed remedial alternatives.  Under the
No Action alternative, the lead agency would take no further action at the site to prevent
exposure to the soil contamination or to treat the soil to protect the ground water.

2.7.1.3  No chemical-specific ARARs were identified for this site.  The No Action alternative
does not address TBC risk-based cleanup levels.  Location-specific potential ARARs are likely
to be met, since it was concluded in the RI that unmitigated impacts to No-Name Creek would
be minimal because the NGA source soils have not been identified as a significant source of
ground-water or surface-water contamination.  No action-specific ARARs or TBCs apply, since
no action is taken under this alternative.

2.7.2  Alternative 2 - Institutional Controls

2.7.2.1  The cost estimate for Alternative 2 is as follows:

                     Capital  Cost:                 $16,500
                     Annual 0 &  M Cost:            $0
                     Present  Worth  Cost:           $16,500
                     Months to Implement:          2 to  6


2.7.2.2  This alternative includes access restrictions, property transfer restrictions,  and
preconstruction assessment procedure to prevent current and future human exposure to
contaminated media at the site.  No measures are taken which address or constitute remediation
of the site.

2.7.2.3  Access Restrictions:  This consists of fencing and active security measures.  Since the
DGSC is a secure federal facility,  site access is already restricted, and the NGA site is fenced.
No additional fences or signs are required.

2.7.2.4  Deed Restrictions:  Administrative and legal mechanisms are in place which will limit
future development at the site.  The transfer of the property known as the Defense General
Supply Center would be in accordance with Section 120(h)  of CERCLA, 42 U.S.C. §9620(h),
and any regulations promulgated thereunder  (See 40 CFR 373).

2.7.2.5  Preconstruction Assessments:  Although current risk evaluation indicates no excessive
risk for construction workers at the NGA site, maintenance and construction activities within the
physical boundaries of the National Guard Area would be controlled through implementation of
existing policies to insure that workers and the public are adequately protected during site
activities.  For military construction projects, a preliminary environmental site assessment
screening  (PEAS) would be performed in accordance with current clearance procedures and
potentially other guidance provided in the DLA-W Policy Memorandum dated 27 December
1989, and would be completed prior to project design within the NGA.  For routine maintenance
or utility operations requiring excavation or trenching,  DGSC's maintenance regulation
(DGSCR) 4150.1 would be modified to require an environmental review in Section III which
is a statement of policy.

2.7.2.6  No chemical-specific potential ARARs have been identified for the NGA soils.  Soil
cleanup levels derived from TBCs would not be met.  However, contact with contaminated soil
media could be prevented.  Location-specific ARARs are likely to be attained, since it was
concluded in the RI baseline risk assessment that unmitigated impacts to No-Name Creek would
be minimal since the NGA source soils have not been identified as a source of ground-water or
surface-water contamination.  No action-specific ARARs have been identified.  Long-term
ground-water monitoring is addressed in OU6, Open Storage Area/Area 50/NGA Ground Water.
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2.7.3  Alternative 4 - Ex-Situ Bioremediation

2.7.3.1  The cost estimate for Alternative 4 is as follows:

                     Capital  Cost:                             $179,000
                     Annual 0 & M Cost:                 $0
                     Preset Worth Cost:                 $179,000
                     Months to Implement:               3 to  6

2.7.3.2  This alternative involves  excavation and biological treatment of the soil.   The
contaminated soil at the site will  be removed and treated on aboveground, lined beds on site.
Necessary nutrients will be added to soil prior to placing the soil on the lined beds.   Organic
contaminants in the soil will be effectively biodegraded under this alternative.

2.7.3.3  Site Preparation/Mobilization:   The site would need to be segregated into zones and
staging areas prior to mobilization for construction.   Staging areas for eguipment storage,  an
office trailer, and operations will be determined prior to construction.  The general work area,
including staging areas, would be fenced to prevent uncontrolled access.  Site preparation
includes the removal of the existing concrete pavement over  the contaminated area.

2.7.3.4  Nutrient Addition and Irrigation System Operation:   The contaminated soils  are placed
in the treatment bed.  Low levels of nutrients (nitrogen and phosphorous),  and possibly
surfactants or wetting agents could be added.  Acclimated microbes may also be added initially
during startup.  The desired range  of soil moisture will be  maintained for treatment.  Increased
oxygen delivery may be obtained by  periodically mixing the soil during treatment.

2.7.3.5  Replacement and Site Restoration:  The treated soil would be sampled for residual
contaminant concentrations and replaced into the excavation.  A base course and new  concrete
pavement would be constructed to match the existing surface  prior to treatment.  After
remediation, long-term ground-water monitoring would be performed under OU6.

2.7.3.6  No chemical-specific potential ARARs have been identified.  Cleanup levels  derived
from TBCs can be met by this alternative.  Location-specific ARARs can be met by controlling
site disturbance during the work.  Potential action-specific ARARs or TBCs, as identified in
Table 2-7 for this alternative,  would be met.

2.7.4         Alternative 5  - Excavation,  Off-Site Disposal

2.7.4.1  The cost estimate for Alternative 5 is as follows:

                     Capital  Cost:                 $267,000
                     Annual 0 & M Cost:            $0
                     Present  Worth  Cost:           $267,000
                     Months to Implement:          3 to  6

2.7.4.2  Site Preparation/Mobilization:   The site will need  to be segregated into zones and
staging areas prior to mobilization for construction.   Staging areas for eguipment storage,  an
office trailer, and truck traffic will be determined prior to construction.  The general work area,
including staging areas, will be fenced to delineate boundaries and prevent uncontrolled access.
Site preparation includes the removal of the existing concrete pavement over the contaminated
area.

2.7.4.3  Excavation:  Excavation will be accomplished using  either a front-end loader or a
backhoe.  Soil will be removed to a depth (maximum estimated to be 6 feet)  at which  additional
testing indicates soil cleanup levels are no longer exceeded.  Excavated soil would  be placed in
trucks and transported to a permitted landfill facility.  The volume of contaminated soils to be
excavated is estimated to be 1340 cubic yards.

2.7.4.4  Additional Testing:   During remediation, further examination and testing of the
underlying soils would be reguired.  The testing would allow confirmation that remediation goals
have been attained.

2.7.4.5  Replacement and Site Restoration:  After the contaminated soil has been removed,  clean
fill would be placed into the excavations, and the concrete  pavement would be replaced.  No
special security or site restrictions will need to be constructed or enforced.  However, a five-
-------
year review of the NGA source soils is required under the current CERCLA requirements.
After remediation, lonq-term qround-water monitorinq would still be required because the
qround water at the NGA is contaminated.  This monitorinq would be performed under OU6.

2.7.4.6  No chemical-specific potential ARARs have been identified for soils.  By removinq
contaminated soils, this alternative is capable of meetinq soil cleanup levels established from
TBCs.  Excavated soil will be stored, tested, and disposed of in accordance with RCRA
requirements.  RCRA ARARs will be stored only if excavated soils are defined to be
"characteristic" hazardous waste.  No "listed" RCRA hazardous wastes are present in the NGA
area.  Excavated soils will be tested for the characteristic of toxicity pursuant to 40 CFR §
261.24.  If the soil exhibits the characteristic of toxicity, it will be manaqed in accordance with
applicable or relevant and appropriate provisions of 40 CFR Parts 261-266, and 268.  These
provisions provide requirements for storaqe, transport and disposal of RCRA hazardous wastes.
For example, if soil wastes qenerated at NGA are determined to be land-disposal-restricted
hazardous wastes under 40 CFR Part 268, then such wastes would have to be store in tanks or
containers and treated prior to disposal.  One form of treatment would be incineration.
Backfillinq with clean soil will comply with RCRA closure requirements, if necessary.  Ambient
air monitorinq and proper handlinq procedures durinq implementation can be used to meet
action-specific ARARs.

2.8    COMPARATIVE ANALYSIS SUMMARY

2.8.0.1  In order to facilitate an effective and meaninqful comparative analysis of the
alternatives, nine descriptive criteria are used in accordance with CERCLA Sections 113, 117,
and 121, and the NCP.  These nine criteria are:

Threshold Criteria

             Overall protection of human health and the environment (overall
              protection)

             Compliance with ARARs

Primary Balancinq Criteria

              Lonq-term effectiveness and
              Reduction of toxicity,  mobility,  and volume throuqh treatment
              Short-term effectiveness durinq construction and implementation
              Implementability (both technical and administrative)
              Cost

Modifyinq Criteria

              State acceptance
              Community acceptance

2.8.1         Overall Protection

2.8.1.1  All of the alternatives except "no action" would provide adequate protection of human
health and the environment by eliminatinq, reducinq or controllinq risk throuqh treatment,
enqineerinq controls, or institutional controls.

2.8.1.2  Alternative 2, (Institutional Controls) would reduce or eliminate human contact by
reliance upon physical controls as well as existinq requlatory and administrative requirements,
and can be effective at preventinq the inappropriate future usaqe of the site and exposure to
contaminated soil.  Alternatives 4  (Ex-Situ Bioremediation) and 5  (Excavation, Off-Site
Disposal) would qo a step further and provide qreater security because the threat posed by the
chemical contamination would be either treated to nearly nondetect levels or removed entirely
from the site.

2.8.2         Compliance with ARARs

2.8.2.1 ARARs and TBC1 requirements for the NGA site were identified durinq the feasibility
study  (see Table 2-7) .  There are no promulqated chemical-specific ARARs for constituents in
soils.  However, USEPA Reqion III has calculated risk-based concentrations  (RBCs) for the
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majority of constituents of concern at the NGA.  These RBCs are included as TBCs.  Due to
the lack of promulgated chemical-specific ARARs, soil action levels were calculated for the
constituents of concern at the NGA using health risk-based estimates.  NGA site is located west
of wetlands identified in the RI, so the state and federal wetlands regulations and reguirements
presently in effect apply.  Proposed action-specific ARARs are identified during the evaluation
of the alternative for the potential remedial actions at this site.  General ARARs for any remedial
actions conducted at the site include Occupational Safety and Health Administration (OSHA)
reguirements for Hazardous Waste Operations and Emergency Response and the OSHA
Recordkeeping and Reporting Reguirements (OSHA. Saftey and Health Standards 29 CFR Part
1910-General Industry and 1926-Construction Industry).

2.8.2.2  Each alternative has been evaluated to determine whether or not it will comply with the
ARARs, as well as TBC reguirements for the NGA site.  A detailed discussion of ARARs and
TBCs is included in the FFS for OU3.  There are not any soil cleanup levels that can be used
as ARARs for soils at NGA site.  However, risk based soil action levels determined to be TBCs
for the site (see Table 2-3)  will be used as cleanup levels unless they are below detection levels
associated with standard analytical methods.

       1 In addition to applicable or relevant and appropriate reguirements,  the lead and support
        agencies may, as appropriate, identify other advisories, criteria, or guidance to be
        considered for a particular release.  The "to be considered"  (TBC) category consists of
        advisories, criteria, or guidance that were developed by EPA, or other federal agencies, or
        states that may be useful in developing CERCLA remedies.  40 CFR §300.400  (g)  (3).

2.8.2.3  Alternatives 4 and 5 will meet the soil cleanup levels by treating or removing the
contaminated soil.  In addition, both alternatives would meet RCRA reguirements for storage,
testing, and disposal.  Alternative 4 would replace soil treated to cleanup levels, and Alternative
5 would import clean backfill.  In either case, RCRA closure reguirements would be met.
Alternatives 1 and 2 will not meet the soil cleanup goals; however, Alternative 2 will prevent
the contact with contaminated soils at the site.  All alternatives will meet the location-specific
ARARs.  Alternatives 4 and 5 will satisfy action-specific ARARs with appropriate regulatory
processing while no action-specific ARARs apply to Alternatives 1 and 2.

2.8.3         Long-Term Effectiveness and Performance

2.8-3.1  Alternative 2 (Institutional Controls) does not remediate the contaminated soil at the
site.  Effectiveness and permanence is based on preventing exposure only.  Long-term
maintenance of controls will effectively prevent contact with contaminated soil.

2.8.3.2  Alternatives 4 and 5 will provide irreversible long-term effectiveness by biologically
reducing and physically removing the contaminants from the soil and contaminated soil from the
site, respectively.  Alternative 1 is not effective at reducing or eliminating existing or potential
exposure at the site.

2.8.4         Reduction of Toxicity,  Mobility,  or Volume

2.8.4.1  Alternative 2 (Institutional Controls) will not provide reduction of toxicity, mobility,
or volume of contaminants and contaminated soil at the site.  However, since DGSC is not
currently planning any changes in site usage, the additional potential for human exposure to
contamination over the long term is not expected to increase significantly under this alternative.

2.8.4.2  Alternatives 4 (Ex-Situ Bioremediation) and 5  (Excavation and Off-Site Disposal) will
provide reduction of toxicity, mobility, or volume of the contaminants by treating or removal
of the contamination at the site.  Alternative 1  (No Action) will leave any contamination as it
is at the site.

2.8.5         Short-Term Effectiveness

2.8.5.1  Alternative 2 (Institutional Controls) and Alternative 1  (No Action) involve no site
disturbance.  No risk to human health or the environment due to remediation activities will be
caused by these alternatives.

2.8.5.2  Alternatives 4 and 5 include soil excavation,  thus measures for dust suppression and
erosion control will be necessary to reduce the risk to human health and the environment during
implementation.  Several months would be necessary to implement Alternatives 4 and 5.
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2.8.6
Implementability
2.8.6.1  Alternative 2 (Institutional Control) is easily and quickly implementable because most
of the primary access control structures currently exist and are enforced at the DGSC.

2.8.6.2  Alternative 1 (No Action) involves no action; therefore, there are no implementability
concerns.  A treatability study may be necessary for Alternative 4  (Ex-Situ Bioremediation) and
approvals need to be obtained to transport and dispose the contaminated soil for Alternative 5
(Excavation and Off-Site Disposal).
2.8.7
              Cost
2.8.7.1  The cost comparison of the alternatives is based on the present worth of an action based
on its estimated period of completion, and on initial capital construction costs and annual
operation and maintenance costs.  Based on those comparisons, Alternative 1  (no action) is the
least costly to implement, Alternative 2 (Institutional Controls) is the next least costly
alternative to implement, followed by Alternative 4  (Ex-Situ Bioremediation), and Alternative 5
(Excavation and Off-Site Disposal).  The alternatives are ranked according to cost as follows:
                     Approach
                     Alternative  1
                     Alternative  2
                     Alternative  4
                     Alternative  5
                     (No Action)
                     (Institutional Controls)
                     (Ex-Situ Bioremediation)
                     (Excavation and
Ranking
1st
2nd
3rd
4th
Cost
$ 0
$16,500
$179,000
$267,000
                                Off-Site Disposal)
2.8.8    Support Agencies Acceptance

2.8.8.1  The EPA and the Commonwealth of Virginia support the preferred alternative.

2.8.9    Community Acceptance

2.8.9.1  Community acceptance of the preferred alternative was evaluated after the public
comment period on the proposed plan for OU3.   The community acceptance is described in the
Responsiveness Summary of this ROD.
2.9
       SELECTED REMEDY
2.9.0.1  Based on the detailed and comparative analysis of alternatives, it was determined that
a combination of the institutional control and excavation and off-site disposal alternatives is the
most appropriate remedy for this site.

2.9.0.2.  A description of each alternative considered and a comparative analysis of alternatives
is provided in the FFS Report for the NGA.  In addition, the support agency suggested that the
alternatives be modified somewhat from those presented in the FFS.  Specifically, the
Institutional Controls alternative was expanded to include several additional items, and the
Excavation and Off-site Disposal alternative was reduced to target the area of contamination
driving the carcinogenic risk.  A description of the selected remedy follows.

2.9.0.3  The selected alternative requires that institutional controls, including access
restriction,  property transfer restriction,  and preconstruction assessment,  be implemented or
continued at  the site.   The selected alternative is primarily aimed at reducing or eliminating
human contact by reliance upon physical controls, as well as existing regulatory and administrative
requirements, and will be effective at preventing the inappropriate future usage of the site and
exposure to contaminated soil.  This alternative effectively reduces risk to an acceptable level
for the main affected population, a future residential use,  by removal of contaminants, and
restricting future use of the site.  The alternative includes:

                     Maintenance of existing fencing and continued use of existing security
                     measures  at the  facility and NGA site;

                     Implementation of existing deed restrictions and property transfer
                     requirements in  accordance with Section  120(h)  of CERCLA,  42 U.S.C.
                     9620  and  any regulations promulgated thereunder;
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                     Continued  implementation  of  existing preconstruction  assessment
                     procedures to  characterize military construction projects  at  the  site,  and
                     policies which cover  routine maintenance  or utility excavations at  the
                     DGSC  facility;

                     Maintenance of existing pavement within the National  Guard Area;

                     Performance of a  follow-up chemical and biological monitoring program
                     for No-Name Creek, until  all OSA/NGA/Area 50  study area  remedial
                     actions are complete;  and

                     A five-year review, to ensure  that the chosen remedy  continues to provide
                     adeguate protection of human health and the environment.

2.9.0.4  In addition to taking advantage of existing site  characteristics, practices,  and structures
to prevent migration of,  or exposure to,  any contamination present at the  site, this  alternative
also prevents future human exposure to contaminated media  at the site.

2.9.0.5  The excavation and off-site disposal portion of this  remedy includes the following
elements:

                     Excavation of  an  area of  organically contaminated soil within the alleged
                     former water treatment disposal area containing the highest  levels  of
                     carcinogenic-related  constituents.   (The  area to be excavated is  centered
                     around soil boring NGASB8, see Figure 2-3.  Reguired  excavation depths
                     are estimated  to  be approximately 2 feet.  The estimated excavation area
                     is approximately  1,100 sguare  feet, and the estimated volume  of material
                     to be removed  is  100  cubic yards).

                    Sampling and analysis  of  soils  at  the  excavation  limits and comparison to
                     risk-based soil action levels  for organic constituents  (see  Table 2-3)  or
                     detectable levels (if detection limits for standard analytical methods  exceed
                     risk  base  levels) to  confirm that contaminated soils  have  been removed;

                    Proper storage  and testing of the  excavated soil  to classify the soil
                     material for off-site disposal in accordance  with RCRA land  disposal
                     reguirements.

                    Transport and disposal of  the contaminated soils  to a  landfill permitted to
                     accept the waste; and

                    Backfilling and regrading  the excavation using clean borrow material.

This alternative is aimed at  reducing the  primary carcinogenic threat at  the  site.  The
combination of Alternatives 2  and 5 will provide  effective protection of  human health and the
environment.

2.9.1         Cost Summary

2.9.1.1  The total estimated  cost of the selected alternatives is  approximately $100,000.

2.10   STATUTORY DETERMINATIONS

2.10.0.1  To meet the statutory reguirements  of CERCLA section 121, the  selected remedy  must:

              Be protective of  human health and the environment;

              Comply with  ARARs (or justify an ARAR waiver);

              Be cost effective;

                     Utilize permanent solutions  and alternative treatment technologies  to the
                     maximum extent practicable;  and

                     Satisfy the preference for treatment that reduces toxicity, mobility,  or
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                     volume  as  a  principal  element,  or  provide  an  explanation  as  to why  this
                     preference is  not  satisfied.

2.10.0.2  How the selected remedy complies with each of these requirements is summarized below.

2.10.1  Protection of Human Health and the Environment

2.10.1.1  The selected alternative will reduce or eliminate potential exposure to contamination
through reliance upon physical controls as well as existing regulatory and administrative
requirements, and will be effective at preventing the inappropriate future usage of the site and
exposures to contaminated soil.  In addition, soil contributing the most risk will be removed and
disposed of off site.  Current exposure is not considered to be of concern since the contaminated
area is under an existing pavement or gravel parking lot, the number of positive detections were
very small, the location of samples having positive detections is in a relatively unused portion
of the site, conservative assumptions were used during risk calculations,  and since exposure to
contaminated soil is unlikely except during intrusive activities.   Any potential future exposures
due to a change in site use (such as residential development),  military construction projects,  or
routine maintenance activities which require excavation,  can be prevented or minimized through
implementation of regulatory or administrative controls.   The selected alternative is not likely
to lead to any unacceptable short term risks.

2.10.2    Compliance with ARARs

2.10.2.1  No chemical-specific potential ARARs have been identified for the NGA soils.  The
excavation to remove contaminated soils will be continued until risk-based concentrations (or
detection limits, where higher) are met.  Location-specific ARARs are likely to be attained,
because it was concluded in the RI baseline risk assessment that unmitigated impacts to No-
Name Creek would be minimal since the NGA source soils have not been identified as a source
of ground-water or surface-water contamination.

RCRA ARARs will be triggered only if excavated soils are determined to be "characteristic"
hazardous waste.  No "listed" RCRA hazardous wastes are present in the NGA area.   Excavated
soils will be tested for the characteristic of toxicity pursuant to 40 CFR § 261.24.   If the soil
exhibits the characteristic of toxicity, it will be managed in accordance with applicable or
relevant and appropriate provisions of 40 CFR Parts 261-266, and 268.  These provisions
provide requirements for storage, transport and disposal of RCRA hazardous wastes.  For
example, if soil wastes generated at NGA are determined to be land-disposal-restricted hazardous
wastes under 40 CFR Part 268,  then such wastes would have to be stored in tanks or containers
and treated prior to disposal.   One form of treatment would be incineration.  Long-term ground-
water monitoring is a component of OU6, Open Storage Area/Area 50/NGA Ground Water.

2.10.3        Cost Effectiveness

2.10.3.1  The combination of institutional controls and limited excavation is considered a cost
effective alternative for this site.  The selected alternative provides overall effectiveness
proportional to its costs, and reasonable value for the dollars spent.

2.10.4  Utilize Permanent Solutions and Alternative Treatment Technologies

2.10.4.1  During the FS study,  treatment technologies were evaluated in comparison with the
selected alternative and it is believed that the combination of alternatives utilizes permanent
solutions to the maximum extent practicable and effectively prevents the inappropriate future
usage of the site and exposure to contaminated soil.  By applying this alternative,  human health
and the environment would be protected both in the present and the future in the most economic
measure.  Alternative treatment technologies were evaluated, but were found to be not
appropriate for this site.

2.10.5  Preference for Treatment That Reduces Toxicity, Mobility,  or Volume

2.10.5.1  Under this alternative, toxicity, mobility or volume of contaminants and contaminated
media at the site will be reduced.   The low-level threat posed by an isolated area of elevated
organic constituents will be removed.  Exposure to contaminants left in place is not considered
to be of concern, because the contaminants are under an existing concrete pavement,  the number
of positive detections were very small, and exposure to contaminated soil is unlikely except
during intrusive activities.  Any potential future exposures due to a change in site use  (such as
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residential development), military construction projects, or routine maintenance activities which
require excavation, can be prevented or minimized through implementation of regulatory or
administrative controls.  Thus, the preference for treatment has been achieved by removing the
highest levels of contamination, while balancing other criteria indicates that leaving other
contaminants in place is an effective solution.

2.10.6        State Acceptance

2.10.6.1  The state has participated in the decision-making process leading to the selected
remedy, and concurred in its selection.

2.10.7        Documentation of Significant Changes

2.10.7.1  The Proposed Plan for OU3 - National Guard Source Area was submitted on July 24,
1995.  The proposed plan identifies a combination of institutional controls and excavation and
off-site disposal as the preferred alternative.  As discussed in the Responsiveness Summary, no
written or verbal comments were received from the public during the comment period.  Thus,
it has been determined that no significant changes to the remedy were necessary.

              3.0 RESPONSIVENESS SUMMARY

3.0.0.1  The purpose of this responsiveness summary is to provide the public with a summary
of citizen comments, concerns, and guestions relating to the area of concern at the Defense
General Supply Center (DGSC) in Chesterfield County, Virginia.  The area of concern
specifically addressed by this responsiveness summary is:

                            Operable Unit  3  (OU3)  -  National Guard  Source Area  Soils

The responsiveness summary details the Defense Logistics Agency's  (DLA)  responses to these
comments, concerns, and guestions.

During the public comment period from July 24 through September 6,  1995, no comments or
phone calls were received by DGSC concerning this operable unit.  A public notice was published
in the Richmond Times Dispatch, a newspaper of general circulation in the area, on July 24,
1995.  In addition, a public meeting was held on August 22, 1995 at the Chesterfield Elementary
School.  At this meeting, DGSC representatives presented slides outlining the proposed plan for
OU3 and the public was given an opportunity to comment on and ask guestions concerning the
plans.  No guestions pertaining to OU3 were asked.  The responsiveness summary for OU3 is
divided into the following sections:

3.0.0.2  The summary is divided into the following sections:

       I.     Public meeting attendance roster

       II.    Panel of Experts

       III.   Newspaper notices and letters announcing dates of the public
              comment period and location and time of public meeting

No public comments were received.  Thus, the decision to select a combination of Alternative 2
(Institutional Controls) and Alternative 5 (Excavation and Off-Site Disposal) as the site remedy
is unaffected.
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                              I

                              PUBLIC MEETING

                             Attendance  Roster

                     ATTENDEES AT PUBLIC MEETING

                      BELLWOOD ELEMENTARY SCHOOL

                      AUGUST 22, 1995 - 7:30 PM

                                                          MAILING
NAME              ADDRESS                                   LIST

 

              II PANEL OF EXPERTS

The following list represents the panel members who participated in the public meeting held on
August 22, 1995.

Defense General Supply Center

George Dellinger
William Saddington
Carol Beecher
Tom Owens

U.S. Environmental Protection Agency - Region III

Jack Potosnak

Virginia Department of Environmental Quality

Steve Milhalko

U.S. Army Corps of Engineers

Sandy Olinger
Morgan Ruther
Suzanne Murdock

Law Environmental, Inc.

Thomas Richardson
Mary Ann Broookshire

                                  III

                              PUBLIC NOTICE

                Richmond Times Dispatch - July 24, 1995

                        Public Meeting

                       Operable  Unit 3



                  Published on Page  B-6  -  Metro Section
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