PB99-963901
                             EPA541-R99-005
                             1999
EPA Superfund
     Record of Decision:
      USA Fort George G. Meade
      (TAP) OU
      Fort Meade, MD
      7/20/1999

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          FINAL
    RECORD OF DECISION

TIPTON AIRFIELD PARCEL (TAP)
      OPERABLE UNIT
  FORT GEORGE G. MEADE
  FORT MEADE, MARYLAND
         JUNE 1999

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                                                                 PAGE
                         TABLE OF CONTENTS
SECTION

DECLARATION FOR THE RECORD OF DECISION REMEDIAL ALTERNATIVE
SELECTION	jv

1.0 DECISION SUMMARY	^
  1.1 INTRODUCTION	          1.1

2.0 SITE INFORMATION	2-1
  2.1 SITE DESCRIPTION	2-1
   2.1.1 Description of AREEs 10 and 11	"!!!"""!."!2-f
3.0 SITE HISTORY AND ENFORCEMENT ACTIVITIES	3.1
  3.1 PREVIOUS ASSESSMENTS AND INVESTIGATIONS	3-1
  3.2 OTHER ARMY ACTIONS AND SAFETY PRECAUTIONS	..^."""3-2
4.0 HIGHLIGHTS OF COMMUNITY PARTICIPATION.....	4-1
  4.1 PUBLIC COMMENT PERIOD	4_1
  4.2 PUBLIC MEETING	.........4--\
  4.3 ADDITIONAL PUBLIC INFORMATION	4_1

5.0 SCOPE AND ROLE OF THE OPERABLE UNIT RESPONSE ACTION	5-1
  5.1 SELECTION OF REMEDY	5.1
6.0 SITE CHARACTERISTICS	6-1
  6.1 SITE TOPOGRAPHY .:	6-1
  6.2 ADJACENT LAND USE	6-1
  6.3 SURFACE WATER HYDROLOGY	6-1
  6.4 GEOLOGY / HYDROGEOLOGY	....6-1
  6.5 ECOLOGY.....'	e-2

7.0 SUMMARY OF SITE RISKS	7-1
  7.1 EXPOSURE ASSESSMENT	7-1
  7.2 HUMAN HEALTH RISK ASSESSMENT FOR AREEs 10 AND 11	7-2
  7.3 ECOLOGICAL RISK ASSESSMENT FOR AREEs 10 AND 11	7-5
  7.4 CONCLUSION	7-6

8.0 DESCRIPTION OF THE "NO FURTHER ACTION" ALTERNATIVE	8-1

9.0 RESPONSIVENESS SUMMARY	9-1
OACA31-94-D-0064                       i                        TAP Operable Unit
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  TAP Ootraole Unit
  Number

  Figure 1
  Figure 2
                                 LIST OF FIGURES
Site Location MAP of the Tipton Airfield Parcel (TAP)
Surface Drainage Features at the TAP OU
  Nurnbej"

  Table 1
  Table 2
                                 LIST OF TABLES
Summary of the Human Health Risk Assessment
Summary of the Ecological Risk Assessment
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 TAP Operable Unit
 LIST OF ACRONYMS
 ASL
 BEC
 BRAG
 CERCLA

 DRMO
 FGGM
 FTA
 EIS
 EPA
 HHA
 HI
 IAL
 MCL
 MDE
 MDNR
 NPL
 ODA
 O&M
 PA
 PRR
 RBCs
 Rl
 ROD
 SARA
 SI
 TAA
 TAP
 TAL
Active Sanitary Landfill
BRAC Environmental Coordinator
Base Closure and Realignment
Comprehensive Environmental Response, Compensation
and Liability Act
Defense Reutilization and Marketing Office
Fort George G. Meade
Fire Training Area
Environmental Impact Statement
U.S.  Environmental Protection Agency
Helicopter Hangar Area
Hazard Index
Inactive Landfill
Maximum Contaminant Level
Maryland Department of the Environment
Maryland Department of Natural Resources
National Priorities List
Ordnance Demolition Area
Operations and Maintenance
Preliminary Assessment
Patuxent Research Refuge
Risk-Based Concentrations
Remedial Investigation
Record of Decision
Superfund Amendments and Reauthorization Act
Site Inspection
Tipton Airfield Area
Tipton Airfield Parcel
Target Analyte List
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 TAP Oaersole Unl
                 DECLARATION FOR THE RECORD OF DECISION
                     REMEDIAL ALTERNATIVE SELECTION
              FOR THE TIPTON AIRFIELD PARCEL OPERABLE UNIT

 Site Name and Location

 Tipton Airfield Parcel Operable Unit (TAP OU)
 Areas Requiring Environmental Evaluation (AREEs) 10 and 11
 Fort George G. Meade (FGGM)
 Fort Meade, Maryland

 Statement of Basis and Purpose

 This Record of Decision (ROD) presents a determination that no further action is
 necessary to protect human health and the environment for the TAP OU which
 includes a final determination for Tipton groundwater, and the following AREEs:

    •  AREE 10    -     Inactive Landfill No. 1 (IAL1)
    •  AREE 11     -     Inactive Landfill No. 2 (IAL2)

 This determination was developed in accordance with the Comprehensive
 Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), as
 amended  by the Superfund Amendments and Reauthorization Act of 1986 (SARA), 42
 U.S.C. §§ 9601 et seq., and the National Oil  and Hazardous Substances Pollution '
 Contingency Plan (NCP), 40 C.F.R. Part 300.

 The no further action decision is supported by documents contained in the
 Administrative Record.

 The State of Maryland concurs with the no further action remedy.

 Description of the Selected Remedy

 A no further action alternative is the selected remedy for the TAP OU.

 Past military training activities resulted in the  presence of unexploded ordnance (UXO)
 at Fort Meade. The Army has previously taken multiple safety measures and actions at
 the TAP OU, some of which are summarized in this ROD. Existing land use
 restrictions, as established by the Tipton Airfield Decision Document (July, 1998) and
 the Decision Document Addendum (November, 1998), include a prohibition on
 conducting any surface or subsurface excavations, digging, well drilling, or other
 disturbances of soil, or below paved surfaces, without prior written approval of the U.S.
 Government.  This approval is also required for activities in the first four feet, where
 there was  previous clearance of ordnance items. Exceptions can be made for
 emergency repair of existing utilities. Residential use without evaluation of residential
 exposure risks is prohibited, as is  groundwater use for any potable or nonpotable
 purposes except for environmental studies. This ROD assesses these previously


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 established land use restrictions and evaluates their protectiveness of human health
 and the environment.

 The Army studied the groundwater, conducting an additional  investigation  after
 ROD for the Tipton Airfield Area (TAA) was signed, to evaluate TAA-wide effects and
 the  potential off-site  impacts related to chemical migration.  This ROD also assesses
 the  previously established land use restrictions and evaluates their protectiveness of
 human health and the environment with regard to groundwater contamination.  The
 remedy for Tipton-area groundwater that is presented in this ROD, is the final remedy
 anticipated by the previous TAA ROD.  Results of groundwater investigations covering
 the  remainder .of the areas  at Fort Meade will not be  necessary for purposes  of
 finalizing the groundwater remediation decision for the Tipton area.

 The selected remedy represents a final remedial action determination with regard to
 soils and groundwater, which together address the contamination at the TAP OU.

 Declaration

 The Rl reports, which include the Baseline Risk Assessment, document the  findings
 associated with the TAP OU. These findings indicate that contaminants detected in the
 environment do not pose an unacceptable risk to human  health and the environment
 under the  conditions of restricted  use.  The risk calculated under the current and
 reasonably anticipated future land use  scenarios for the TAP OU is within the EPA's
 acceptable  risk  range.    Previously  established  land-use  restrictions focus  on
 maintaining these land.use assumptions.

 The  Rl  report  for  IAL#3  also  documents Maximum   Contaminant  Level  (MCL)
 exceedances of the  volatile organic compound,  benzene, in well MW3-2 during two
 sampling  rounds.   Benzene has  an MCL  of 5.0 /zg/l.  The  average benzene
 concentration detected during the two sampling events is 9.05 /ug/l. The Rl investigation
 did not reveal a likely source area.  Although the average concentration of 9.05 ^g/l
 exceeds the MCL, the risks associated with benzene in the Tipton area groundwater as
 a whole were relatively low.   Even if  the groundwater were used residentially, the
 benzene risks would  be as follows: for a child, the Hazard Index (HO would be 0.04; for
 an adult, the HI would be 0.07; and the cancer risk woufd be 2 x 10 . Therefore, it has
 been determined that benzene is not a risk driver for groundwater.

 An isolated detection of 2-amino-4, 6-dinitrotoluene was observed at 0.522 /ugA in well
 MW3-2.  This compound,  an explosives degradation  product, was detected  at lower
 depths (Arundel  Confining Layer) during one of two sampling rounds.  This  isolated
 detection resulted in an HI less than 1 for commercial/industrial use scenarios.

 4-amino-2,6-dinitrotoluene was detected in both sampling rounds in well MW3-2.  The
 average sample  concentration  is 28.6 vg/l resulting in a HI of 2 (EPA Region 3 risk-
 based screening  concentration =  2.2  ^g/l;  Hazard  Quotient of 1).  The area-wide
 evaluation of groundwater concluded that the contamination was not originating from an
 identifiable source area  within the  TAP, but was the result of past activities  at  Fort
 Meade.    There is no  known  carcinogenic   risk  associated with  4-amino-2,6-

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 dinitrotoiuene.  The aminoaiiwotoluenes (particularly 4-A-2.6-DNT) are associated
 His graater than  1 for grounciwater use by workers or residents.  Because cf the /and
 use restrictions already in effect it has been determined that no exposure pathways to
 the pucfic exist due to this class of contaminants, provided restrictions continue. Tnis is
 also  true  of metals, bis(2-etryihexyi)pnthala:e,  and acetophenone, wnich  could
 contribute  further to risks (both carcinogenic  and noncarcinogenic) if  residential
 receptors were ever exposed to the groundwater. In addition, a study of groundwater
 migration dees not indicate expected migration of these chemicals :o off-post residential
 wells  above unacceptable  concentrations.  Given the relatively low concentrations of
 the aminocinitrotoluenes, the iack of a known carcinogenic rsk relating to this class of
 contaminants, :he lack of ar. identifiable source of these contaminants within the TAP.
 and the lack of an exposure route, it has been determined that no active groundwater
 remediation Is required.

 Because of these findings, every two years after the data of the ROD. groundwatar will
 be sampled from certain  weils. Monitoring results will be provided to EPA. MDE, snd
 the Army. In addition, the Tipton area will be inspected to assure compliance with the
 land use restrictions.  A review every 5 years  will be  conducted to evaluate the
 frequency and need  for continued  monitoring.  This is  to ensure  that the remedy
 continues to provide adequate protection of human health and the environment This is
 the final planned response action for the TAP OU.
                                                   Al
 ,/bHN D. FRKETIC      .                          Date £   77
^cJlonel. Military intelligence
 Commanding
 A3RAHAM FERDAS                       .      Date
 Director, Hazardous Site Cleanup Division
 U.S. EPA Region ill
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 1.0   DECISION SUMMARY
 1.1 INTRODUCTION

 On April 1, 1997, Fort George G. Meade (FGGM) was proposed for inclusion on the
 Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA^
 National Priorities List (NPL). FGGM was added to the final NPL on July 28,1998
 A CERCLA remedial action is often divided into OUs. As defined in the National Oil
 and Hazardous Substances Pollution Contingency Plan (NCP), an OU means a
 discrete action that comprises an incremental step toward comprehensively addressing
 site problems.  This discrete portion of a remedial response manages migration or
 eliminates or mitigates a release, threat of a release, or pathway of exposure  The
 cleanup of a site can be divided into a number of OUs, depending on the complexity of
 the problems associated with the site. OUs may address geographical portions of a
 site, specific site problems, or initial phases of an action.  OUs may also consist of any
 set of actions performed over time or any actions that are concurrent but located in
 different parts of a site. This ROD presents a determination that no further action is
 necessary to protect human health and the environment at the TAP OU which consists
 of IAL1 and IAL2 (see Figure 1), located at Fort Meade, Maryland. This no further
 action decision is the final action for the TAP OU.

 Based on the previously taken safety measures and actions, including restrictions on
 future land use, and the results of the risk evaluation, it was determined that the TAP
 OU poses no current or future potential, unacceptable human health risks. Therefore
 the conditions at the TAP OU do not require further action to be protective of human '
 health and the environment..

 A feasibility study, which normally develops and examines remedial action alternatives
 for a site, was  not performed for the TAP OU since the results of the risk evaluation
 indicate that no further remedial action is required.
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 Record of Decision-  Tipton Airfield
3000
3000
6000 Feet
 Tipton Property Boundary for Record of Decision
 Property included in Record of Decision signed December 1998
 Inactive Landfill #1 and #2

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                                                                  inal fteconj of Decision
 2.0   SITE INFORMATION

 2.1 SITE DESCRIPTION
                                •s-     .    j('**.
 Fort George G. Meade (FGGM) is located in Fort Meade, Maryland.  FGGM formerly
 occupied 13,596 acres of land in the northwest corner of Anne Artmdel County  The
 site is a Base Closure and Realignment Act of 1988 (BRAC) parcel, located east of
 State Route 198 and south of Highway 32.  It is bounded on the west by the Baltimore-
 Washington Parkway and by the Patuxent River to the south.  The Amtrak railroad track
 right-of-way and State Route 175 form the southeast and northeast site boundaries,
 respectively.

 The facility was authorized by Congress in 1917 as a  training cantonment for troops
 dunng World War I. The U.S. Government commandeered 4,000 acres, most of which
 was then farm land, and named the installation Camp Meade in honor of Major General
 George G. Meade.  In January 1941, additional training areas were added within the
 installation, expanding the post  to 13,596 acres.   During the  1940s,  the facility
 underwent widespread growth to accommodate several regiments who moved their
 base of operations to FGGM, including  the Second  U.S.  Army and the Eleventh
 Cavalry. Tipton Army Airfield was completed in 1963, replacing a small airstrip  which
 had been in operation since 1928.

 In 1988, the Defense Authorization Amendments and Base Closure and Realignment
 Act of 1988 mandated the closure and/or realignment of approximately 9,000  acres,
 encompassing the southernmost two-thirds of the installation.  In 1991, the Army
 transferred 7,600 of the 9,000 acres to the Department of the Interior's Patuxent
 Research Refuge (PRR), formerly known as the Patuxent Wildlife Research Center. A
 second land transfer of approximately 500 acres  to the PRR took place in January
 1993.

 2.1.1 Description of AREEs 10 and 11

 2.1.1.1  Site Location and Operational History of AREE 10 - Inactive Landfill 1
 (IAL1)

 IAL1 is located  in the north-central portion of the BRAC parcel between the  Little
 Patuxent River and  Bald Eagle Drive.   IAL1 is  considered part of the  Tipton Airfield
 parcel although it is physically separated from the airfield by the Littfe Patuxent River.  A
 small concrete blockhouse, formerly used as a communications building, is present on
 the  northwest comer of the  area.   The  PRR  has  recently erected a cluster of
 outbuildings on the west side of Bald Eagle Drive, west of IAL1, which are collectively
 known as the Hunter Control Station.

 According to the Enhanced  Preliminary Assessment (PA) report (USAEC, 1989), IAL1
 was used  as  an unlined  sanitary landfill  from approximately 1950 to 1964.   No
 information has been found indicating the types of material disposed of at this location.
 Select historical aerial photographs of IAL1, compiled by the USEPA (1990 and 1996),
 are presented in  the Final Rl report (USAGE, 1998a).  The earliest known aerial
 photograph (1938) shows IAL1 as a cultivated field. In subsequent aerial photographs

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 from 1943  1952, and 1957, IAL1 appears as an open clearing or training area, with no
 evidence of ground scarring or landfill activity. Landfill activities were first indicated in
 aerial photographs from  1963, which show barren areas and what  appear  to  be
 trenches, probable debris, and mounded material presumably associated with landfill
 activities (USEPA, 1990).  Aerial photographs from 1970 on show the area as inactive
 The 1963 treelme, which appears to correspond to the maximum extent of man-made
 activities, persists to the present.  Areas of mounded materials located on the north side
 of IAL1, which were first observed on the; 1970 photographs, also persist to the present.

 IAL1 has an approximate  extent of 16 acres as indicated on Figure 1.  This  boundary
 was developed  based on the  extent of historical operations, aerial photographs and
 subsequent site investigation activities.   A  possible former  burial trench  location,
 corresponding to the  mounded area and  an area of strong magnetic responses was
 tentatively located in the northern part of IAL1.

 2.1.1.2 Site Location and Operational History of AREE 11 - Inactive Landfill 2
 (IAL2)

 IAL2 is located within the BRAG parcel on approximately  10 acres of land north of New
 Tank Road (now Wildlife  Loop),  approximately 450 feet north and  east of  the Little
 Patuxent River.  The  bulk of IAL2 is separated from the PRR by the perimeter fence
 which runs along New Tank Road then turns north along the western side of IAL2.  A
 dirt access  road runs north, from a locked  gate in the fence, through  IAL2  to Tipton
 Airfield.  Other unnamed tracks provide access to the area between IAL2 and the Little
 Patuxent River.  No buildings or structures are present at IAL2.  The approximate extent
 of IAL2 is indicated on Figure 1. This boundary was developed based on the extent of
 historical operations, aerial photographs, and subsequent site investigations.

 Select  historical aerial  photographs of  IAL2 from  USEPA  photo compilations are
 presented in the Final Rl report (USAGE, 1998a). IAL2 was initially operated as  a soil
 borrow  area. Large active excavations are  apparent in  aerial photographs from 1938
 and 1943 (USEPA, 1996).  By 1952, the borrow area was mostly overgrown. According
 to the Enhanced PA (USAEC,  1989), the area was subsequently operated as an
 unlined rubble disposal area.  In 1957 and 1963, at its maximum extent, mounded
 materials and probable fill material are visible in the southern portion of the area.  IAL2
 was little used between 1963 and 1970, with  aerial photographs showing the area being
 increasingly revegetated. A single north-northwest trending trench is visible along the
 east side of the access road  in  1970 (USEPA, 1990).   Continued disposal activity
 occurred after 1980 in the northern portion of IAL2 where graded and disturbed areas
 are visible in 1986.  During Rl  fieldwork,  piles of rubble  material (brush, concrete and
 asphalt debris) which  appear to be of more recent origin were observed in a marshy
 area on the north side of IAL2.

 The Enhanced PA report (USAEC, 1989) referred to a potential encounter with mustard
 gas canisters  in the mid-1950s  northwest  of IAL2.   An attempt was made by the
 installation to locate the burial site using geophysical methods, but proved inconclusive
 (USAEC, 1992b). The Final Environmental Impact Statement indicates that the FGGM

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                                              —   	                  .  ' "a* '^cn-l/' U U' isdCiSIQn

  Directorate of Engineering and Housing concluded that there was no further reason to
  suspect the presence of mustard agent buried on-post.
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                                                                inal RecorO ofCeasion
       SITE HISTORY AND ENFORCEMENT ACTIVITIES
 3.1  PREVIOUS ASSESSMENTS AND INVESTIGATIONS
 Several environmental investigations have been performed at FGGM since BRAC '88
 incuding  an Enhanced PA (USAEC, 1989), a study by the Maryland Department of
 I/SSn  ?QnorKxeS (~DNR)>  an Rl . *  Site Inspection (SI) Study
 (USAEC .19925),  a Draft SI Addendum (which  included  an Environmental Impact
 Statement (EIS) and a Wetland Identification Study) (USAGE, 1991), an Ordnance and
            (°E) Removal Action (USAGE, 1997), Rl  reports (USAGE 1998a  and

                                                     Reutilization and Marketin9
 The Enhanced PA includes a review of all available records related to air, soil  surface
 water, and groundwater,  and identifies six  areas  of concern requiring  additional
 investigation  at  FGGM:  active and  inactive  landfills, underground storage tanks
 asbestos, unexploded ordnance, surface water, and burning grounds.
                                   *
 MDNR conducted an evaluation of the surplus property in January 1990. The study
 describes the natural features  and land uses associated with the 9,000 acres to be
 excessed from FGGM and discusses the degree of development of the retained land.

 In January 1991, a wetland identification study was prepared by RGH/CH2M Hill, Inc. to
 complete the study of the closure and use/reuse alternatives for  the 9,000-acre parcel
 at FGGM (USAEC, 1994).  The report describes the methods used to identify wetlands
 on the parcel and presents a map of wetlands distribution.

 A Final EIS for the comprehensive base realignment and partial closure for FGGM and
 Fort Holabird was prepared by the U.S. Army Corps of Engineers, Baltimore District, in
 August, 1991. This report focuses on the environmental and socioeconomic impacts
 associated with the planned base realignment and partial closure at FGGM and  Fort
 Holabird. The EIS covers the 9,000-acre BRAC parcel at FGGM.

 A Draft SI  report was submitted by EA Engineering, Science and Technology (EA) in
 January,  1992. This report discusses conditions at the Helicopter Hangar Area (HHA)
 four inactive  landfills (IAL1 to  IAL4), the DRMO, the  Fire  Training  Area (FTA), the
 Ordnance Demolition Area (ODA), underground  storage tanks,  and asbestos   The
 Final SI was submitted in October 1992 (USAEC, 1992b).

 A Draft SI Addendum (SJA) report, prepared by Arthur D. Little,  Inc., addresses data
 gaps identified in the previous  SI report (USAEC, 1994a).  The SIA focused on the
 following  six areas of investigation:  DRMO Salvage Yard, the FTA, the HHA, IAL2, the
 ODA, and Soldiers Lake.  Another study, a  Remedial Investigation Addendum (RIA),
 was conducted concurrently with  the  SIA (USAEC,  1993a).  Two sites, the Active
 Sanitary Landfill (ASL) and the Clean Fill Dump (CFD),  are included in the RIA study.
 The results of the RIA are reported as a separate document.  However, some basewide
 data, such as geology, general hydrogeology, and background soil concentrations, are
 reported in both reports.

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     .-..- _                        " -- — - — -- _ _ . _ '   ecor o  sc/ston
 Tint™ A  Jf^   Wa,S conducted ^ Human Factors Applications, Inc. (HFA) over^hT
 Tiptop Airfield parcel in  1996 (USAGE, 1997a).  With the exception of the inferior area!
 of the mac** andfill sites and areas beneath water, all unpaved areas o the parcel
 were searched for potential UXO to a depth of four feet.
    HthM' 1"8a and USACE' 1998b> of 'ALL IAL2, IAL3, the CFD the FTA
 and the HHA were prepared by ICF Kaiser.  In addition, an ecological risk assessment
                                    '                                **
 «nHSaJnPpn9 ra-3 f°r the DRMO area (USACE, 1999) was recently approved by EPA
 and  MDE.  Th.s report investigated the  potential for the DRMO area to act as an
 upgradient  source for groundwater contamination in the Tipton area   Thfe Rl  data
 ?]± ?"?" d8teZ'?e d  It;3* the DRM° 3rea Was not imPactin9 tne groundwater at £
 ISLhi     :t  While other groundwater studies will still be conducted for  separate
 operable units at Fort Meade, no other upgradient areas are suspected as sources of
 Tipton area groundwater contamination.                                  »"">** OF

 The  Rl reports for the TAP were  performed to characterize potential environmental
 contammafon and to conduct baseline ecological and human health risk assessments
 The  Summary of the Risks" section presents the results of the risk assessments.
 A,c« * ARMY ACTIONS AND SAFETY PRECAUTIONS TAKEN IN THE TIPTON
 AIRFIELD AREA

 The following is a list of many actions and safety precautions taken by the Army at the
 I f\F\.
    Ordnance Survey (1994): The Army commissioned an ordnance survey covering all
    areas of the airfield to assess the extent of ordnance remaining at the  site and
    surrounding areas. During this survey, ordnance was searched for to a depth of six
    inches below the surface, and  10%  of  the  remaining area  was surveyed for
    ordnance to a depth of five feet.  During this action, a total of 1 ,400 ordnance items
    were recovered from the site and surrounding areas.

    Ordnance Clearance  M995-1997V The  Army searched for  ordnance  from all
    accessible areas  to a four-foot  depth.  Inactive landfill areas, wetlands  and all
    paved  surfaces were  excluded.   During this action,  1,548 ordnance  items were
    recovered, rendered safe, and disposed of. In addition, more than 33 tons  of scrap
    (concrete, metal,  and  miscellaneous debris)  were recovered incidental to  the
    ordnance removal. Much of this material was  recycled at local facilities.

    Miscellaneous Debris Removal (Summer 1998V Several items that were identified
    during  ordnance removal projects were recovered for disposal.  Items removed
    included several 55-gallon drums  and an old vehicle-mounted storage tank.

   Ordnance Safety  Measures.  Inactive  Landfill 3  M998): The Army  performed
   ordnance survey work  in and around IAL3. The safety plan for this area includes

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    developing a long-term monitoring plan for the site.  The first step in this effort was
    to identify the depth of soil cover over any landfill debris at this site.  The Army will
    now develop a schedule for periodic surface sweeps of the area to ensure that no
    ordnance items have migrated to the surface through frost action.

 •  Ordnance Safety Measures. Inactive Landfill 2 M9981: IAL2, located at the southern
    most end of the Tipton parcel, could not be cleared of suspected ordnance because
    the  area contains large amounts  of rubble debris and is partially composed of
    wetlands with a shallow water table. The selected response action.for this site was
    the installation of a passive engineering control consisting of a seven-foot high chain
    link fence with three-strand barbed wire surrounding the entire site.  The  fence ties
    into an existing like fence along Wildlife Loop Road, and encompasses an  area of
    24.68 acres that will be retained by FGGM. IAL2 will not be included in the Tipton
    parcel transfer to Anne Arundel County.

 •  Ordnance  Safety Measures. Building Debris Site /1999}r The Army took  additional
    ordnance safety measures at a 2 1/2-acre  area designated  as  the Building  Debris
    Site. Because of  its central location, this area has  been made a priority  for reuse.
    The selected response action for the site  is a combination of additional  ordnance
    clearance and construction of a vehicle parking lot.

 *  Ordnance Safety Measures. Inactive Landfill 1  (1998-19991: The selected response
    action for the site  is a combination of ordnance clearance to a  four-foot depth and
    construction of  a  safety cover.   During  this action,  54  ordnance  items  were
    recovered, rendered safe, and disposed.  In addition, more than 760 tons of scrap
    (concrete,  metal,  and  miscellaneous  debris)  were  recovered incidental  to the
    ordnance removal, and recycled at local facilities. The area of  IAL1 not cleared of
    suspected  ordnance is approximately 5.5 acres. A three-foot thick safety cover has
    been constructed.

 In summary, the Army's prior response actions  address the explosives risks related to
 UXO and protect human health and the environment. The specifics  of the Tipton
 Airfield Decision Document (July, 1998), and the Decision Document Addendum
 (November, 1998) include the establishment and enforcement of land use restrictions,
 initially via the FGGM  Master Plan and, subsequent to property transfer, via deed
 restrictions. Existing land use restrictions include a prohibition on conducting any
 surface or subsurface excavations, digging, well drilling,  or other disturbances of soil, or
 below paved surfaces, without prior written  approval of the U.S. Government. This
 approval is also required for the first four feet which was previously cleared of ordnance
 items. Exceptions can be made for emergency repair of existing utilities.  Groundwater
 use at the TAP is restricted for any potable or non-potable purposes  except for
 environmental studies. Furthermore, the existing land use restrictions prohibit
 residential use of the property without evaluation of residential exposure risk.
DACA31-94-D-0064                                                      TAP Operable Unit
ESPS03-6                                                            Fort George G. Meade
JUNE 1999                                                               Final Document
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                                                                Piftaf &ecgr& ofOecision
 4.0   HIGHLIGHTS OF COMMUNITY PARTICIPATION

 4.1 PUBLIC COMMENT PERIOD

 The Army provided a 30-day comment period from April 21,1999 to Mav 21  1999 to
 prov.de an opportunity for public involvement in the decision-making process During
 the comment penod, the public was invited to review the Proposed Plan and the
 environmental investigation reports. These reports were made available to the public
 and are located in the Administrative Record. The Administrative Record is the body of
 documents that forms the basis for the selection of a particular response at a site  The
 Administrative Record includes documents that support the response decision  relevant
 wpr^nnltlhatHWKe? ^ "f?" i" Selectin9the response action, and documents that
 were considered but not used in the decision making process.


 belowdm'niStratiVe Re°0rd W3S made available to  the Public at me locations listed

 1)    Provinces Public Library
       2624 Annapolis Road
       Severn, MD 21144
       Phone:  (410)222-6280
       Hours: Mondays, Tuesdays and Thursdays  -1:00 p.m. to 9:00 p m •
             Wednesdays and Saturdays - 9:00 a.m. to 5:00 p m • and
             Fridays - 1:00 p.m. to 5:00 p.m.

 2)    U.S. Army
       Directorate of Public Works
       Attn: ANME-PWE, Bldg. 239
       2-1/2 Street and Ross Road
       Fort Meade, MD 20755
       Phone: (410)962-7677

 4.2  PUBLIC MEETING

 The Army held a public meeting on the Proposed Plan on May 12,1999 at 7'00 p m to
 accept oral comments. The meeting was held at the EPA Environmental Science
 Center at Fort Meade.  This meeting provided an opportunity for the public to comment
 on the Proposed Plan.  No comments were received during the public meeting.

 4.3 ADDITIONAL PUBLIC INFORMATION

 The Proposed Plan provided a summary of the actions considered and the results  of
 environmental studies conducted at the TAP OU. The public is encouraged to consult
 the Administrative  Record for a more detailed explanation.

 The notice of availability of the Proposed Plan document was published in the Baltimore
 Sun on April 21. 1999 and in the Capitol Gazette April 22,  1999. A Responsiveness
 Summary, included as part of this ROD, has been prepared to respond to the
 comments, criticisms, and any new relevant information received during the comment
                                                                 TAPOperab.eUn,t
JUN  ie»q                                                        Fort George G. Meade
JUN5 1999                                                            .
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 period.  Upon signing the ROD, the Army will publish a notice of availability of this ROD
 in the Baltimore Sun and the Capitol Gazette, and place the ROD in the Administrative
 Record located in the repositories mentioned above.
OACA31-94-D-0064                                                         TAP Operable Unit
ESPS03-6                                                              Fort George G. Meade
JUNE 1999                                                                  Final Document
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 TAP Ooeraole Unit
 \ 5.0   SCOPE AND ROLE OF THE OPERABLE UNIT RESPONSE

 5.1 SELECTION OF REMEDY

 This ROD, the second for the Fort Meade NPL site, presents the selection of the final
 remedial alternative for soils dnd groundwater at the TAP OU, which together address
 all of the known contamination at the TAP OU.  In addition, the final groundwater
 remedy in this ROD serves as the final remedial alternative for the TAA OU  This ROD
 does not address other OUs at Fort Meade. The remaining OUs are currently under
 independent investigations and will be addressed separately in future Proposed Plans
 and RODs.

 No further  action is necessary  at the TAP OU to protect human health  and the
 environment.  Under the no further action alternative, no remedial action will be taken at
 ?f0 £M OU based uP°n botn tne current level of risk posed by contamination at the
 TAP OU and the protectiveness provided  by prior actions. This is the final response
 action for the TAP OU.

 Based upon these findings, the remedy also requires that every two years after the date
 of this ROD, groundwater will be sampled  from certain wells. Monitoring results will be
 provided to EPA, MDE, and the Army. In addition, the Tipton area will be inspected to
 assure compliance  with the  land use restrictions.  A  review every 5 years will  be
 conducted to evaluate the frequency and need for continued monitoring.  This is to
 ensure that the remedy continues to provide adequate protection of human health and
 the environment. This is the final planned response action for the TAP OU.
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 16.0   SITE CHARACTERISTICS
 6.1 SITE TOPOGRAPHY

 The TAP OU lies within the Coastal Plain Physiographic Province. The site is
 characterized by low roiling uplands and low-gradient streams. Within the TAP OU the
 relief vanes over a range of approximately 90 feet (ft); the lowest elevation (90 ft)  '
 occurs within the Little Patuxent River; whereas the highest elevation (180 ft) occurs on
 the northern boundary of the TAP OU. The majority of the site topography, which has
 been modified to accommodate the airfield, slopes gently to the west or south.
 6.2 ADJACENT LAND USE

 The TAP OU is bordered to the north by State Highway 32. The OU is bounded to the
 south, east, and west by the Department of Interior's Patuxent Research Refuge (see
 i igure i ).

 6.3 SURFACE WATER HYDROLOGY

 Figure 2 shows the surface drainage features at the TAP OU. Runoff originating within
 the penmeter portions of the TAP OU is conveyed by drainages west or south to
 tnbutanes or drainages of the Little Patuxent River.  Runoff from the central portion of
 the area flows into a stormwater collection and conveyance system beneath the airfield
 which discharges, via french drains, to the Little Patuxent River or its drainages.
 6.4 GEOLOGY / HYDROGEOLOGY

 FGGM is located on the unconsolidated sands, clays, and silts of the Coastal Plain
 which were deposited from the  Cretaceous to the Quaternary geologic periods  The
 Coastal Plain sediments dip and thicken to the east and southeast.
 The surficial deposits present beneath the TAP OU are primarily from the lower
 Cretaceous age Potomac Group. Quaternary alluvium and river terrace deposits are
 locally present adjacent to the Little Patuxent River.  The Potomac Group consists of
 from youngest to oldest, the Patapsco Formation, Arundel Clay, and Patuxent
 Formation. The lower portion of the Patapsco Formation outcrops at the TAP OU  It
 consists of up to 40 feet of silty sands. Airfield construction fill was locally obtained
 from this unit. The Arundel Formation consists of massive beds of red, brown and gray
 clay with local zones of more permeable layers. The Arundel Clay is approximately 265
 feet thick. The Arundel Clay was penetrated during Rl activities at IAL2.  The Patuxent
 Formation consists of a thick sequence of sand-rich sediments which are underlain by
 crystalline bedrock of the Baltimore Mafic Complex at 600 to 800 feet below ground
 surface.

 At the TAP OU, the water table  is present, generally at depths less than  ten feet below
 ground surface, within the lower portion of the Patapsco formation. The water table
 aquifer extends down to the top of the Arundel Clay and has a maximum saturated
 thickness of approximately 25 feet in this area. Unconfined groundwater flow is
 controlled by topography and flow is generally west or south toward the Little Patuxent
 River. The Arundel Clay acts as a regional confining layer below the Patapsco aquifer.
 However, groundwater is locally found in confined  or semi-confined sand lenses within
 the upper portions of the Arundel Clay. The Patuxent Aquifer, which  is present
JUNE 1999                                                         Fort George G.Meade
JUNE 1999                                                             Fjna| Doajmen,

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  INACTIVE
LjLANDI
                             INACTIVE^ '
                             LANDFILLX'
                                2
                                                                      STREAM OR DRAINAGE
                                                                      ROAD
                                                                   «  BUILDING
                                                                 	APPROXIMATE EXTENT OF ENVIRONMENTAL STUDY
                                                                      AREAS ADDRESSED IN THIS RECORD OF DECISION
    PRR
   . VISITOR
   I CUNfE
                                                                                         BALTIMORE DISTRICT
                                                                                   US  Army Corps of  Engineers
                                                                          CONTRACT NO. 0 AC A31 -94-0-0064  FORT GEORGE G. MEADC
FIIE:  TA-SW
DATE: 06-14-99
                                                                          FIGURE 2
                                                                           TIPTON  AIRFIELD   DRAINAGES

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 TAP Ooertola Unit	_^

 between the Arundel Clay and bedrock, is a regionally important groundwater source
 Regional groundwater flow in the Patuxent aquifer is to the east-southeast.
 6.5 ECOLOGY
 The habitat in the TAP OU has been heavily altered and is likely to only support limited
 flora and fauna typical of disturbed urban/light industrial areas.  As delineated the TAP
 OU contains no wetlands or protected or endangered species. Wetlands protected
 species, sensitive environments are present in nearby areas of the PRR and the Little
 Patuxent River. Any drainage from the TAP OU would flow, via surface runoff or the
 airfield stormwater management system into the Little Patuxent River. An ecological
 nsk assessment has concluded that there is a very limited potential for adverse effects
 to terrestrial plant and invertebrate communities and to aquatic life (USAGE, 1998a)
                                                                    TAP Operas Unit
 ,m <<                                                            Fort Geof9e G- Mea{je
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  7.0    SUMMARY OF SITE RISKS
  —•————^—____^____^^_-_____

  7.1  EXPOSURE ASSESSMENT

 Cancer risks are expressed as numbers reflecting the increased chance that a oerson
 tWhe chee±,f fnC6rA Jf h,fhe JS direCtly 6XpOSed ^9" through woZg  aJ the s'S) to
 p«™?  ™-      m 'ue Qroundwater and soil at the site over a period of time   For
 example EPA's acceptable risk range for Superfund sites is 10^ to 1CT6 meanha 'there

 mi,nonn M^firr " ^ ^Sanf (1 X 1°^ to one additionarcSTon:
 mimon (1x10) that a person will develop cancer if exposed to a certain hazardous
 substance. The nsk associated with developing other health effects is e^ressed as an
 aLWnt'Ch, 'S, the, r?i0 °f the SXiSting level of 6XP°sure to contaminants at a Ite to an
 acceptable level of exposure. At or below an HI of 1 , adverse effects are  not expected
 A HI is also used to evaluate ecological risks.                             expected.
              indUC!ed b0t,h ecol°9ical and human health risk assessments to address
            .ent  and future risks posed  to human health and the environment
 associated w,th the s.te. The human health risk assessment was based on exposure to
 soil surface water, sediment, and supplementary evaluations of groundwater  The
 ecological  nsk assessment was based on exposure to soil,  sediments, and surface
 t^a In       Assessment included estimates of the risk posed to human health and
 he environment assummg the  continuation of the current  industrial (non-residential)
 rnnll? sf nan°' as we» as risk in «he absence of restrictions, or in the event of
 contaminant m,grat.on.   The establishment of land use restrictions  eliminates the
 exposure route to the contaminated groundwater and, therefore, protects human health
 SSriH? env'L°nment  Thf groundwater assessment supports the continuation of these
 restnctions. The current land use scenario estimates the level of risk posed by Fort
 Meade s current use  of the land.  The current land use scenario is based on the
 assumption that the property remains under  U.S. Government authority to enforce
 existing land use restrictions and continues in current  or like use and assumes the
 migration to off-site receptors will not occur at unacceptable levels.

 Existing land use restrictions, as established by the Tipton Airfield Decision Document
 (July,  1998) and the  Decision  Document Addendum  (November,  1998)  include a
 prohibition on conducting  any surface or subsurface excavations, digging, well drilling
 or other disturbances of soil,  or below paved surfaces, without  prior written approval of
 the U.S.  Government.   This approval  is also required for the first four feet which was
 previously cleared of ordnance items. Exceptions can be made for emergency repair of
 existing utilities.  Groundwater use at the Tipton area is restricted for any potable  or
 nonpotable purposes except for environmental studies.

 DACA3 1 -94-D-0064                        ~~ - ' -   ,.  • - : -
ESPS03-6                                        '                    TAP Operable Unit
JUNE 1 999                                                         Port Ge°rge G. Meade
                                                                    Final Document

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 TAP Operabla Unit	

 In the unlikely event that the site's use would change, the property will revert back to
 the U.S. Government.  The human health risk assessment will need to be evaluated for
 residential receptors  in  the unlikely event that the site  would be developed for
 residential use.

 Local hydrogeology shows shallow groundwater discharging to surface waters prior to
 leaving the Tfpton area.  After several decades, sanitary waste maten'als at the TAA
 and TAP do not appear to be degrading groundwater quality in the shallowest saturated
 zone (water  table aquifer),  with the  exception  of the  inorganics arsenic,  iron,
 manganese, and chromium. Of this group, arsenic most frequently exceeds risk-based
 screening guidance.  Arsenic, which may be naturally occurring, has been found to be
 pervasive throughout  the TAA and TAP, both  in the study areas .and in background
 samples of soils, sediments, and groundwater. The concentrations of detected iron and
 manganese are within published regional values and also may be occurring naturally.

 The aquifers underlying the TAA and TAP are used as sources of groundwater by
 residents located off-post to the east (i.e., regionally downgradient).  However, based
 on existing information regarding the nature/extent of chemicals and hydrogeology, the
 likelihood that chemicals from the Tipton area are migrating to these residential wells is
 unlikely. Furthermore, the Tipton area does not appear to be significantly impacting the
 shallow aquifers.  Large sections of clay in the upper portions of the Arundel Clay Layer
 and  high hydraulic head differences between the shallow and deep wells in the western
 part of  the TAA  suggest  little potential for communication between  the water table
 aquifer  and the deeper confined aquifers.  Groundwater samples collected from the
 upper portions of the  Arundel Clay  at  IAL#3  (where MCL exceedences for certain
 contaminants  have been  identified)  show a  westward gradient toward the Little
 Patuxent River.  Downgradient wells in the upper portions of the Arundel Clay did not
 show this contamination.  Overall,  a downward vertical gradient is evident between the
 shallow and  deep monitoring wells.   Data from other areas suggest that deeper
 water-bearing  zones in the Arundel Clay may follow the deeper  regional  flow to the
 east.

 7.2  HUMAN HEALTH RISK ASSESSMENT FOR AREES 10 AND 11
 Two potential human  receptors were identified based  on current and  reasonably
 anticipated future land use:

 •  Worker contact (dermal  contact and  incidental  ingestion) with surface soils and
   worker ingestion of groundwater (supplemental assessment); and

 •  Trespassers: soil ingestion and dermal contact; surface water dermal contact;
   sediment ingestion and dermal contact

 Even though residential use is not anticipated in this area  and no target receptors exist
 due to land use restrictions, residential calculations for groundwater were evaluated for
 informational purposes only.
DACA31-94-D-0064                                                     TAP Operable Unit
ESPS03-6                                                           Fort George G. Meade
JUNE 1999                                                              Final Document
                                       7-2

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 TAPPoet-sole Unit
                                                                    Final Recora of Decision
 Health risk levels, determined  using EPA  Guidelines  to  ensure that co
 estimates  of potential  health effects,  differ  depending  on the assumed        se
 because human exposure differs with land use.  As  outlined  above, a conservative
 estimate  of  nsk  was  developed  incorporating  the  potential exposure pathways
 rS 9, TSPt0rf tha!, mf-y be exp°sed t0 soil' Q^ndwater, surface water, and
 sediment at the s.te and wh.ch were evaluated  in the risk assessment included daily
 workers and occasional recreational users.                                         y

 Levels below^ unacceptable risk-based concentrations of pesticides were widely  if
 infrequently, found.  Metals were ubiquitous.  Based on the  reasonably  anticipaied
 future  and use,  risk  associated with direct contact with the environment under
 occupation^ or recreational scenarios were at the low end of EPA's acceptable risk
 range of 10 to 10* The His calculated using the same reasonably anticipated future
 and use were all below 1.  Additionally, since these risks are driven mainly by metals
 they appear to be  partially or wholly due to inorganic chemicals that may be occurrinq
 naturally.                                                                       y
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JUNE 1999
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 TAP OoaraO/e Unit
                                                                     Final Reconj of Decision
              TABLE 1 - SUMMARY OF THE HUMAN HEALTH RISK ASSESSMENT
         In the following table, cancer risk estimates are compared with the USEPA's target
         risk range for health protectiveness at Superfund sites of 1 xirr* to 1xicr*.
         The potential for adverse non-carcinogenic effects was assessed by comparing the
         non-carcinogenic hazard indices to a value of 1. An HI less than 1 indicates that
         adverse non-carcinogenic health effects would not be expected to occur
Medium of Concern
Surface soil
Receptors - Site worker and trespasser pathways
Incidental ingestion by site workers:
Dermal absorption by site workers:
Incidental ingestion by trespassers:
Dermal absorption by trespassers:
Surface Water
Receptor- Trespasser pathway
Dermal absorption by trespassers:
Sediments
Receptor- Trespasser pathway
Incidental ingestion by trespassers:
Dermal absorption by trespassers:
Qroundwater (Supplemental Assessment)
Receptor — Future site worker pathway
Incidental ingestion by site worker:
AREES10&11
Cumulative
Cancer Risk

8x1 0'7
2x10*
2x1 0'7
2x1 0'7


9x1 0*


9x1 0'7
3x1 0's


2x1 CT5
Cumulative
Hazard Risk

<1 (5x1 0"3)
<1 (1x10~2)
<1 (3x1 cr3)
<1 (3x1 0"3)


<1 (1x1 0'2)


<1 (9x1 0"3)
<1 (2x1 0'2)


3x10°
As always, the physical hazards associated with UXO  are a  potential concern.  Fort
Meade has already conducted  UXO  surveys at the site to address  this risk.  As
discussed previously, an Ordnance and Explosives (OE) Removal was conducted by
Human Factors Applications, Inc (HFA) over the Tipton airfield parcel, in 1996 (USAGE,
1997a).   With the exception of the interior areas of the inactive landfills, all unpaved
areas of the parcel were searched for potential UXO to a depth of four feet.  Other UXO
work performed by the Army is also discussed in this ROD.

An isolated detection of 2-amino-4, 6-dinitrotoluene was observed at 0.522 ^g/l in well
MW3-2.   This compound, an  explosives degradation product, was detected at lower
depths (Arundel Confining  Layer) during one  of two sampling rounds.   This  isolated
detection resulted in an HI less than 1 for commercial/industrial use scenarios.

4-amino-2,6-dinitrotoluene was detected in both sampling rounds in well MW3-2.  The
average  sample concentration is 28.6 ^gl\  resulting in a HI of 2 (EPA Region 3 risk-
based screening concentration  = 2.2 /zg/l; Hazard  Quotient of  1). The  area-wide
evaluation of groundwater concluded that the contamination was not originating  from an
identifiable  source area within the TAP,  but was the result of past activities at Fort
Meade.    There is  no  known  carcinogenic  risk  associated  with   4-amino-2,6-
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 TAP Operable Unit	
            -    "•              i                                     Final Record of Decision
 dinitrotoluene. The aminodinitrotoluenes (particularly 4-A-2.6-DNT) are associated with
 His greater than 1 for groundwater use by workers or residents.  Because of the  land
 use restrictions already in effect, it has been determined that no exposure pathways to
 the  public exist due to this class of contaminants, provided restrictions continue This is
 also true of  metals,  bis(2-ethylhexyl)phthaiate,  and  acetophenone,  which could
 contnbute further to  risks  (both  carcinogenic and noncarcinogenic)  if residential
 receptors were ever exposed to the groundwater.  In addition,  a study of groundwater
 migration does not indicate expected migration of these chemicals to off-post residential
 wells above unacceptable concentrations. Given the relatively low concentrations of the
 aminodinitrotoluenes, the lack of a  known carcinogenic risk relating to  this class of
 contaminants, the lack of an identifiable source of  these contaminants within the TAP
 and the lack of an exposure route, it has been determined that no active groundwater
 remediation is required.

 The Rl  report also documents MCL exceedances of the volatile organic compound
 benzene, in well MW3-2 during two sampling rounds.  Benzene has an MCL of 5 o'^g/l
 The average benzene concentration detected during the two sampling events was 9 05
 A*g/l. The Rl investigation did not reveal a likely source area. Although the average
 concentration of 9.05 /*gi\ exceeds the MCL, the risks associated with benzene in the
 Tipton area groundwater as a whole were relatively  low.  Even if the groundwater were
 used residential^,  the benzene risks would be as follows: for a child, the HI would be
 0.04; for an adult, the HI would be 0.07; and the cancer risk would be 2 x 10"6.
 Therefore, it has been determined that benzene is not one of the risk drivers for
 groundwater.

 7.3  ECOLOGICAL RISK ASSESSMENT FOR AREES 10 AND 11
 The following pathways were identified as sources of potential exposure:

 •  Root uptake from contaminated soil;

 •  Contact and absorption, incidental ingestion, and feeding on contaminated  food and
   soil; and

 •  Bjoaccumulation from vegetation or animal prey.

 The ecological risk assessment evaluated exposure  of terrestrial and aquatic receptors
 from surface soil, sediments, and surface water exposures from the site. The use of
 the site  as the approach area for the airport located on the TAP will discourage
 terrestrial ecological receptors.

 Several metals (including chromium, aluminum, and  vanadium) and  low levels of
 pesticides exceeded the ecological screening criteria for the  various plant and
 invertebrate receptors. The site's commercial and/or occupational use will discourage a
 diverse  plant community.  This will also significantly reduce the natural habitat of
terrestrial receptors. By considering the reasonably anticipated future land use and


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  TAP Ooerable Una
  expected management practices, the results support the plan for no further action at the


       TABLE 2 - SUMMARY OF THE ECOLOGICAL RISK ASSESSMENT (ERA)
          Medium of Concern
          Surface soil
           Effects to:
            (a) Terrestrial plant
                communities; and
            (b) Terrestrial invertebrate
                communities (as
                represented by
                earthworms)
           Pathways: Direct contact with
           chemicals
AREEs 10 and 11 (ERA Findings)
Minimal risk - Aluminum, chromium, and
vanadium exceeded the earthworm TRVs at all
sample locations. However, the detected
background concentrations also exceeded plant
TRVs, suggesting the on-site concentrations are
at many locations, reflective of the local/regional
soil type, in which case earthworms are likely to
be adapted to these levels.
 7.4  CONCLUSION

 Because the human health and ecological risk assessments concluded that site
 conditions, in light of the existing land-use restrictions established under the prior
 response action, do not pose an unacceptable risk to potential human and ecological
 receptors, no further action is deemed appropriate to protect human health and the
 environment.
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JUNE 1939
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 TAP Operable Unit
 8.0   DESCRIPTION OF THE "NO FURTHER ACTION" ALTERNATIVE
 The selected remedy for the TAP OU is no further action.  At the time of this ROD
 future land-use of the TAP OU was determined to be an industrial airport  The TAP OU
 was used as a military airfield from the early 1960s to September 1995, when it was
 closed.  The airport conversion of this airfield was initially planned as a partnership
 between Howard County and Anne Arundel County.  Anne Arundel County currently

 wnf inH?.HeoaSl°tn thff K bUi'dingS 3t the TAP OU'  The second lease- which is Pending,
 will include additional hangar areas, the runway and taxiways.

 The current land-use scenario is based on the assumption that the property remains
 under U.S. Government authority to enforce existing land-use restrictions and continues
 in current or hke use. When title to this BRAG property is transferred, the restrictions on
 future and use will be embodied in the deed. The U.S. Government will retain the
 ability to enforce those use restrictions established in prior Decision Documents  In
 addition, after transfer of title to the property, in the unlikely event that the TAP OU's
 use as an airport would change, title to the property will revert back to the U S
 Government. A human health risk assessment will need to be evaluated for residential
 receptors in the unlikely event that the TAP OU would be developed for residential use

 Because of these findings, every two years after the date of this ROD, groundwater will
 be sampled from certain wells.  Monitoring results will be provided to EPA, MDE and
 the Army. In addition, the Tipton area will be inspected to assure compliance with the
 land use restrictions. A review every 5 years will be conducted to evaluate the
 frequency and need for continued monitoring. This is to ensure that the remedy
 continues to provide adequate protection of human health and the environment This is
 the final planned response action for the TAP OU and groundwater in the Tipton Area
 which includes the TAA OU.
DACA31-94-D-0064
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                                      8-1
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  TAP Oparaoie Unit
 19.0   RESPONSIVENESS SUMMARY
  The purpose of the Responsiveness Summary is to provide the public with a summary
  of citizen comments, concerns, and questions regarding the TAP OU. No comments
  were rece.ved during the 30-day public comment period9 from April 21, 1999 to May 21,

                                                   the
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                                       9-1
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