EPA/ROD/R03-95/212
                                    1995
EPA Superfund
     Record of Decision:
     DOVER AIR FORCE BASE
     EPA ID: DE8570024010
     OU03
     DOVER, DE
     03/28/1995

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Text:
    THE DECLARATION FOR THE RECORD OF DECISION
    REMEDIAL ALTERNATIVE SELECTION

    Site Name and Location

        Oil/Water Separator at Building 918 (Site OT 40)  Dover Air Force Base (D
    County,  Delaware.
    Statement of Basis Purpose

        This Record of Decision presents the selected remedial action for the Oi
    Building 918 Operable Unit (Site OT 40)  which was chosen in accordance with
    of the Comprehensive Environmental Response, Compensation, and Liability Act
    (CERCLA),  as amended by the Superfund Amendments and Reauthorization Act of
    (SARA) and,  to the extent practicable, the National Oil and Hazardous Substa
    Contingency Plan  (NCP),  40 C.F.R Part 300.  This decision is based on the Ad
    Record for the site.

        The State of Delaware, in a letter dated May 5, 1994 to DAFB and the Env
    Protection Agency (EPA),  concurs with the selected remedy.  The information
    remedial action decision is contained in the information repository for the
    located at the Dover Public Library, Dover,  Delaware.
    Summary of Site Risks

        There are hazardous substances present in the shallow groundwater at lev
    would cause risk.  Additionally, arsenic and lead exist in soils at levels w
    background levels.  The site poses a minimal risk to public health, welfare,
    Remedial Alternatives

        Three alternatives were evaluated and include:  1)  No Action; 2)  Removal
    3)  Removal,  Soil Excavation, and Off-Site Disposal.

        The No Action alternative requires no actions be taken at the site.  Thi
    as a baseline for comparison and CERCLA requires it be evaluated.  It is the
    at this site because the other alternatives offer no substantial advantages.

        Alternative 2 involves removal and decontamination of the O/W separator
    piping for off-site disposal.  The O/W separator is a gravity fed system com
    The soil surrounding the separator would remain under this alternative.  The
    would be backfilled with clean soil,  covered with an engineered soil cap and

        Alternative 3 would be as outlined under Alternative 2,  excepting that t
    the O/W separator would be characterized.  All contaminated soil would be re
    disposal.  The site would then be backfilled with clean soil and reseeded.

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Description of the Selected Remedy

    The selected remedy is for no further response action to be taken.  The
the base long-term monitoring program to ensure that contaminant levels rema
would cause a threat to human health or the environment.
Declaration Statement

    It has been determined that no significant risk or threat to human healt
exists from exposure to current conditions at this site.  Therefore, no acti
provide adequate protection to human health and the environment.
Conclusion

    The No Action alternative provides protection of human health and the en
cost effective.
EDWIN E. TENOSO
Lieutenant General, USAF
Air Mobility Command
Chairperson, Environmental
  Protection Committee
    THOMAS C.  VOLTAGGIO
         Hazardous Waste Management
    Division Director
              Environmental Protection
           Region III
Record of Decision
Oil/Water Separator at Building
Base, Kent County, Delaware
918 (Site OT 40)  Dover Air Force
                           Decision Summary
Introduction

Dover Air Force Base  (DAFB),  in consultation with the U.S.
Environmental Protection Agency (EPA) and the State of Delaware,
Department of Natural Resources and Environmental Control
(DNREC),  has evaluated all available data for the Oil/Water  (O/W)
Separator at Building 918.  This Record of Decision (ROD) has
been prepared by DAFB, the lead agency for response actions at
the site, to present the selected alternative for this operable
unit.
The ROD utilizes information developed during a site

-------
investigation  (SI) conducted in May 1991, field screening data
gathered during the spring of 1993, and from comments on the
Proposed Plan received during the Public Comment period.

The Proposed Plan for this site was issued on March 27, 1994.  It
was available for public review, along with the rest of the
information repository for the Administrative Record, at the
Dover Public Library.
Site Name, Location & Description

The O/W Separator at Building 918 is located in the northeastern
portion of DAFB.   DAFB is located in Kent County, Delaware, 3.5
miles southeast of the City of Dover (Fig 1).   Bounded to the
southwest by the St. Jones River, DAFB comprises approximately
4000 acres, including annexes, easements, and leased property
(Fig 2).   The surrounding area is primarily cropland and wetlands
with limited residential areas.
Site History and Enforcement Actions

DAFB began operation in December 1941 as a U.S. Army Air Corps
coastal patrol base.  In August 1943, the mission of the base
changed to an operational training base for combat aircraft and
development of air-launched rockets.

The base was deactivated in September 1946.  From 1946 to 1950,
the base was used periodically by the Air National Guard.  In
July 1950, the base was reactivated and designated DAFB.  In
March 1952, the base came under the command of the Military Air
Transport Service  (MATS) and the mission changed from air and


land defense to cargo operations.  Currently, DAFB is under the
Air Mobility Command  (AMC) and is home to the C-5 Galaxy
Aircraft, providing global strategic airlift capability.

The surface topography of DAFB is relatively flat, with
elevations ranging from 10-30 feet above mean sea level.  Surface
water runoff is handled by an extensive storm drainage network of
open ditches and pipe culverts.  The storm drainage network

-------
discharges to the St. Jones River, the Pipe Elm Branch and the
Morgan Branch.

The soils underlying DAFB consist mainly of silty sands.  Depth
to ground water varies across the base from 8 to 15 feet below
ground surface  (BGS).  Shallow ground water is contained within
the Columbia Aquifer.  The Columbia Aquifer consists of medium-
to-coarse sand with gravelly sand, gravel, silt, and clay lenses
common throughout.  The saturated thickness of the Columbia
Aquifer ranges from 15 to 20 feet in the western portion of the
base to 70 feet in the eastern portion.  Since the Columbia is the
shallowest aquifer, it is the most prone to degradation.  The
Columbia Aquifer is not used as a source of drinking water in the
area surrounding DAFB.

Wastes generated by DAFB are directly related to activities
supporting the various aircraft that have been stationed at the
base over the years.  Hangars for maintenance of aircraft and
support vehicles line the main aircraft parking area,  many of
these hangers have floor drains connected to the base industrial
waste collection drain or directly to the sanitary sewer.  O/W
separators are installed between the floor drains and the sewer
mains to intercept any petroleum products which may be washed
into the floor drains.  This O/W separator is the only identified
potential source of contamination in this operable unit.

The O/W Separator at Building 918 was installed in 1959 to
service Hangars 918 and 922 and is still in use.  The hangars
currently house heavy equipment for maintenance shops.
Historically, these buildings were aircraft maintenance
facilities .

The O/W Separator is located below ground on the northwest side
of Building 918 (Fig 3).   It is constructed of reinforced
concrete and measures 7 feet wide by 9 foot long by 7 feet deep.
The O/W Separator works by gravity separation.  A 400-gallon
holding tank is used to accumulate waste oil, while the separated
water is discharged to the sanitary sewer.  Separated oils are
collected monthly by Base personnel for storage and subsequent
disposal by a civilian contractor.  There has been no previous
federal or state enforcement or permitting activity regarding
this O/W Separator.

When DAFB was listed on the National Priorities List  (NPL) in
1989, the O/W separator at Building 918 was identified as having
the potential to release hazardous substances to the environment.

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Highlights of Community Participation

In accordance with Sections 113 and 117 of CERCLA, DAFB held a
public comment period from March 27, 1994 through April 25, 1994
for the proposed remedial action described in the Site
Investigation report  (SI) and Proposed Plan.  These documents
were made available to the public in the Administrative Record
maintained at DAFB and the Dover Public Library.  Public notice
wan provided via publication in Dover's Delaware News newspaper.
During the public comment period, no comments nor a request for a
public meeting were received.  Therefore, no public meeting was
held.
Scope and Role of the Operable Unit

The final remedial action for this operable unit described below
addresses the soil at the O/W separator at Building 918.
Remedial actions for neighboring operable units at DAFB will be
evaluated and presented as data becomes available from the
basewide remedial investigation and feasibility study.  The
selected remedy is consistent with the strategy for remediating
DAFB, the Comprehensive Environmental Response, Compensation and
Liability Act of 1980 (CERCLA),  as amended by the Superfund
Amendments and Reauthorization Act (SARA) and, to the maximum
extent practicable, the National Contingency Plan (NCP).
Summary of Site Characteristics

During the 1991 SI, four soil borings were drilled adjacent to
the O/W separator, one on each side  (Fig 4).   Samples were
collected from 0 to 2 feet and 8 to 10 feet BGS in each boring
and analyzed for volatile organic compounds (VOC),  semi-volatile
organic compounds  (SVOC),  and lead.  The VOC,  1, 1, 1-tri-
chloroethane (TCA), was detected at an estimated concentration
of 1 ug/kg (micro  grams per kilogram, or parts per billion) in a
single shallow soil sample collected from SI boring Bill.
Acetone and methylene chloride were also detected in the soil
analysis.  The maximum soil concentrations for acetone and
methylene chloride were 13 ug/kg and 27 ug/kg, respectively.
Benzole acid was detected in a single shallow soil sample
collected from SI  boring B109, at a concentration of 88 ug/kg.
No other SVOCs were detected.  Lead concentrations in the soil
ranged from 0.59 to 17.8 mg/Kg (milligrams per kilogram, or parts
per million),  with the higher concentrations generally found in
the shallow surface samples.

Organic constituents detected in soil samples collected during
the SI that may be attributable to site conditions were
restricted to two  shallow samples  (i.e., at 0 to 2 feet).  These
isolated constituents are benzole acid and 1,  1, 1-TCA.  Acetone

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inorganic analytes detected in the soil sample exceeded these
levels, and the detections are believed to represent natural
levels for this area.  Lead was detected at a concentration of
3.5 mg/kg in sample BGP3019, which is of the same order of
magnitude as detected during the previous investigation and is
below the natural range  (10 to 20 mg/kg) reported for Delaware
soil.
                      Table 1

                        OT40 (918)
                  CHEMICAL DATA FOR SOIL

                   TAL METALS  (mg/kg)
Site ID:
Location ID
Sample ID:
SDO:
     OT40
     918
     BDL3019
699069
Sample Data:
     03/23/93
Depth  (feet):    10.0-12.0
OT40
918
     BDL3019D
699069
03/23/93
10.2-12.0
USOS Range(a)
  Delaware
95 * Confidence
     Upper Bound
      Eastern U.
L V
ALUMINUM
ANTIMONY
ARSENIC
BARIUM
BERYLLIUM
CADMIUM
CALCIUM
CHROMIUM
COBALT
COPPER
IRON
LEAD
MAGNESIUM
MANGANESE
MERCURY
NICKEL
POTASSIUM
SELENIUM
SILVER
SODIUM
THALLIUM
VANADIUM
ZINC
3960
6.
2.
10.
0.
1.
107.
4.
2
5
2270 00 *
3.50
149.
14.
0.
8
892.
0.
2.
96.
0
5.
3.90 B
00
,50
,50
,00
,68
,10
,00
,60
70
60


,00
,70
,11
60
,00
,68
,30
,30
68
,50

* J
UN UJ
S
B
U
U
B
*
U
U
3150
J
B
*
U
U
U
UN UJ
U
B
U
B
5.
L
V
4280.

1.
11.
0

188
6
2.
5
00 *

219
20
0.
8

,40
,80
68

00
30
,70
60


00
30
,11
60
6.
B
B
U
1
B
*
U
U

2.
B
*
U
U
892

2.


6
30

,30


80

0
U

0
B

00 * J 15.000-30.
50 UN UJ <1
<0.1-2.7
300-500
BDL
10 U
1.500-1.700
10-50
5
3-7
5.000-10.000
90 J 10-20
500-1.000
70-100
0.03-0.05
<5-7
00 U
68 UWN UJ
—
137 00 B 2.000
68 U 2.8-7
10-30
17-29 178
000 272
2.9
31
1.600
3.5
—
32.000
223
39
102
115.000
53
26.000
3.800
0.05
77
27.000 (c
1.8
—
-5.000
19.2
271

a)  Shacklette and Boerngen.  1981.
b)  Geometric mean of data times standard devistion squared
  (Shacklette and Boerngen.  1981)
c)  Arithmetic mean of data plus two standard devistions
  (Shacklette and Boerngen.  1981)
-------
BDL = Below detection level
-- * Value not available.
 The ground water probe sampling location was positioned adjacent
to SI boring Bill, because it contained the most constituents
(Fig 4).   Ground water samples GP3019 and GP3019D were collected
at a depth of 23.5 feet and were analyzed for target compound
list (TCL) VOCs, TCL SVOCs, TCL pesticides/polychlorinated
biphenyls (PCBs), and Target Analyte List (TAL)  filtered and
unfiltered metals.  For accelerated chemical results, a sample
was also analyzed for selected VOCs at an on-site laboratory.

The ground water sample submitted for on-site analysis contained
chloroform at a concentration of 2 ug/L (micrograms per liter, or
parts per billion) and 8.1 ug/L (Table 2).   Chloroform was also
detected in the off-site analysis at concentrations of 2 ug/L and
3 ug/L.   Chloroform detections in the off-site analyses were
removed during the validation process on the basis of blank
contamination (Table 3).   Chloroform in the on-site sample was
well below the maximum contaminant level (MCL)  for total
trihalomethanes of 100 ug/L.  Chloroform is also a common
laboratory contaminant and, as such, is not considered to be a
contaminant of concern at this site.

Bis  (2-Ethylhexyl) phthalate was detected in ground water at
estimated concentrations of 2 ug/L and 3 ug/L.   This compound was
also detected in the associated blanks.  Bis (2-Ethylhexyl)
phthalate is commonly used in the manufacture of rubber products
such as laboratory gloves.  Since the compound was detected in
the associated blanks at low estimated concentrations, its
validity is questionable.  Detected concentrations are well below
the MCL of 6 ug/L and do not pose a threat.

The pesticides heptachlor and lindane were detected at low,
estimated concentrations of 0.0015 ug/L and 0.0012 ug/L,
respectively.  However,  no pesticides were detected in the
duplicate sample.  These concentrations are well below their
respective MCLs of 0.4 ug/L and 0.2 ug/L.   Additionally, the
presence of these pesticides is questionable, because they were
not confirmed in the duplicate sample.  The only known use of
pesticides at this location is an occasional application to
control insects.

Both total and dissolved inorganic constituents were analyzed for
at the site.  As expected for most analytes, the total
concentration of most inorganic analytes exceeded the dissolved
concentration.  Chromium and lead exceeded MCLs in the total
metals (unfiltered)  sample.  However, no constituents exceeded
MCLs in the dissolved metals (filtered) sample.   Comparing
results of the total metals to the dissolved metals clearly
indicates that the elevated concentrations of almost all the
metals in the unfiltered  (total) sample are the result of the
high sample turbidity.  Only sodium was detected at a higher
-------
concentration in the filtered sample than in the unfiltered
sample.  Filtered samples are more representative of actual
ground water conditions; therefore, the concentrations in  the
                      Table 2

                     OT40 (918)
                   CHEMICAL DATA FOR GROUNDWATER
                     ONSITE ANALYSIS

                   SELECTED VOCs  (ug/L)
Site I.D.
Location I.D.
Sample I.D.
Sample Date
Depth  (feet)

Vinyl Chloride
Freon 113
1,1-DCE
Methylene Chloride
1-1,2-DCE
Chloroform
1,1,1-TCA
TCE
PCE

Benzene
Toluene
Ethylbenzene
Total Xylenes
OT40
918


23.
NT
<0.
<1.

<5.
2
<0.
<0.
<0.
<2.
<2.
<2.
<2.



5

5
0

0

5
5
5
0
0
0
0
OT40
918
GP3019
03/23/93
23.5

<0 . 5
<1 0
<2.0
<5 0

<0 . 5
<0 . 5
<0 . 5
<2 0
<2 . 0
<2 . 0
<2 . 0
                    GP3019D
                    03/23/93
                   FINAL
                                MCL
               NT
               <2 0
                       70

                      200
                     5
                     5

                     5
                     1000
                      700
                    10000
                             100
Source:  Drinking Water Standards - EPA  (May  1993) Drinking Water  Regulation
  and Health Advisories, Office of Drinking Water, Washington,  D.C.
                      Table 3

                        OT40 (918)
                CHEMICAL DATA FOR GROUNDWATER
Site ID:
Location ID:
Sample ID:
SDO:
Sample Date:
Depth  (feet) :
57
TCL VOCs (ug/L)

  OT40
  918
  GP3019

  03/23/93
  0.0
                   OT
130
918
GP3019D

03/23/93
0.0
                                           MCL
                                          FINAL
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                                 V
                                                  V
1,1,1-TRICHLOROETHANE
1,1,2,2-TETRACHLOROETHANE
1,1,2-TRICHLOROETHANE
1,1-DICHLOROETHANE
1,1-DICHLOROETHENE
1,2-DICHLOROETHANE
1,2-DICHLOROETHENE
1,2-DICHLOROPROPANE
2-HEXANONE
4-METHYL-2-PENTANONE
ACETONE
BENZENE
BROMODICHLOROMETHANE
BROMOFORM
BROMOMETHANE
CARBON BISULFIDE
CARBON TETRACHLORIDE
CHLOROBENZENE
CHLOROETHANE
CHLOROFORM
CHLOROMETHANE
CIS-1,3-DICHLOROPROPENE
DIBROMOCHLOROMETHANE
ETHYLBENZENE
METHYL ETHYL KETONE
METHYLENE CHLORIDE
STYRENE
TETRACHLOROETHENE
TOLUENE
TRANS-1,3-DICHLOROPROPENE
TRICHLOROETHENE
VINYL CHLORIDE
XYLENE  (TOTAL)
          10 U
                10  U






10
10
10
10
10
10
10

10
10
10
2
10

10
10


10

10

10
10
10






U
U
U
U
U
U
U

U
U
U
J
U

U
U


U

U

U
U
U
10
10
10
10
10
10







10





10


10
8

10

10



U
U
U
U
U
U





UJ
UJ
U



U

U


U
BJ

U

U



                  UJ
                  U








10
10
10
10
10
10
10

10
10
10
3
10

10
10


10

10

10
10
10








U
U
U
U
U
U
U

U
U
U
J
U

U
U


U

U

U
U
U
10 U

10 U

10 U
10 U
10 U
10 U







10 U



U

10 U


10 U
10 U

10 U

10 U



200
10 U
5
10 U
7
5
70
5



5
100
100


5
100

100


100
700


100

1000

5
2
10000
                       Table 3  (cont'd)
Site ID:
Location ID:
Sample ID:
SDO:
Sample Date:
Depth  (feet) :
TCL SVOCs  (ug/L)

          OT40
     918
     GP3019
57            130
     03/23/93
     0.0
     OT40
918
GP3019D

     03/23/93
0.0         FINAL
MCL
                               V
1,2, 4-TRICHLOROBENZENE
1,2-DICHLOROBENZENE
1,3-DICHLOROBENZENE
1,4-DICHLOROBENZENE

10 U
10 U
10 U
10 U
L V
10 U
10 U
10 U
10 U

70
600
600
75
-------
2,4,5-TRICHLOROPHENOL
2,4,6-TRICHLOROPHENOL
2,4-DICHLOROPHENOL
2,4-DIMETHYLPHENOL
2,4-DINITROPHENOL
2,4-DINITROTOLUENE
2,6-DINITROTOLUENE
2-CHLORONAPHTHALENE
2-CHLOROPHENOL
2-METHYLNAPHTHALENE
2-METHYLPHENOL
2-NITROANILINE
2-NITROPHENOL
3,3-DICHLOROBENZIDINE
3-NITROANILINE
4,6-DINITRO-O-CRESOL
4-BROMOPHENYL PHYENYL ETHER
4-CHLORO-3-METHYLPHENOL
4-CHLOROANILINE
4-CHLOROPHENYLETHER
4-METHYLPHENOL
4-NITROANILINE
4-NITROPHENOL
ACENAPHTRENE
ACENAPHTHYLENE
ANTHRACENE
BENZO(A)ANTHRACENE
BENZO(A)PYRENE
BENZO(B)FLUORANTHENE
BENZO(G,H,I)PERYLENE
BENZO(K)FLUORANTHENE
BIS(2-CHLORO-l-METHYLETHYL)
BIS(2-CHLOROETHOXY) METHANE
BIS(2-CHLOROETHYL) ETHER
BIS(2-ETHYLHEXYL) PHTHALATE
BUTYL BENZYL PHTHALATE
CARBOZOLE
CHRYSENE
DI-N-BUTYL  PHTHALATE
DI-N-OCTYL  PHTHALATE
DIBENZOFURAN
DIBENZ(A,H)ANTHRACENE
DIETHYL PHTHALATE
DIMETHYL PHTHALATE
FLUORANTHENE








10

10
25
10

25
25


10

10
25
25
10
10
10

10
10
10
10
ETHER




10
10
10
10
10











U

U
U
U

U
U


U

U
U
U
U
U
U

U
U
U
U





U
U
U
U
U



25 U
10 U
10 U
10 U
25 U
10 U
10 U
10 U

10 U



10 U



10 U

10 U






10 U






10 U

10 U





10 U
10 U
10 U








10

10
25
10

25
25
10 U

10

10
25
25
10
10
10

10
10
10
10
10
10 U

2 BJ
UJ
10
10
10
10
10











U

U
U
U

U
U


U

U
U
U
U
U
U

U
U
U
U
U




U
U
U
U
U



25 U 70
10 U
10 U
10 U
25 U
10 U
10 U
10 U

10 U



10 U R


10 U UJ
10 U

10 U

UJ




10 U 0.1
0.2
0.2

0.2
10 U
10 U
10 U UJ
U 3 BJ U
10 U





10 U 0.3
10 U
10 U
                                                   100
          10  U
10 U
Site ID:
Location  ID:
Table 3  (cont'd)

 TCL SVOCs  (ug/L)

   OT40        OT40
   918              918
-------
Sample ID:
SDO:                 57
Sample Date:
Depth  (feet):
FLUORENE
HEXACHLOROBENZENE
HEXACHLOROBUTADIENE
HEXACHLOROCYCLOPENTADIENE
HEXACHLOROETHANE
INDENO(1,2,3-CD)PYRENE
ISOPHORONE
N-NITROSODIRHENYLAMINE
N-NITROSODIPROPYLAMINE
NAPHTHALENE
NITROBENZENE
PENTACHLOROPHENOL
PHENANTHRENE
PHENOL
PYRENE
GP3019

03/23/93
0.0
GP3019D
130
03/23/93
0.0
03/23/93
0.0
L V
10 U





10 U







10
10
10
10
10

10
10
10




U
U
U
U
U

U
U
U
        10 U

        10 U
        10 U
        10 U
25 U
                                         V
                                      MCL
                                     FINAL
                                                10 U
                            10 U
10 U

10 U
10 U
10 U
10 U
10 U
10 U
10 U

10 U
10 U
10 U

25 U
 UJ
                                       UJ
                                   1

                                  50
                                                 0.4
                       Table  3  (cont'd)

                        TCL  PESTICIDES/PCBs (ug/L)
Site ID:
Location ID:
Sample ID:
SDO:
Sample Date:
Depth  (feet) :
4,4-DDD
4,4-DDE
4,4-DDT
ALDRIN
ALPHA-BHC
BETA-BHC
CHLORDANE-ALPHA
CHLORDANE-GAMMA
DELTA-BHC
DIELDRIN
ENDOSULFAN I
ENDOSULFAN SULFATE
ENDRIN
ENDRIN ALDEHYDE
ENDRIN KETONE
HEPTACHLOR
HEPTACHLOR EPOXIDE
LINDANE
METHOXYCHLOR
57
OT40
918
GP3019
03/23/93
0.0
L V
0.1000
OT40
918
GP3019D
130
03/23/93
0.0
L V
U UJ 0,
0.1000
0
0
0
0
0
0
0
0
0

0
0
0
0

0
0
.1000
.0500
.0500
.0500
.0500
.0500
.0500
.1000
.0500
0,
.1000
.1000
.1000
.0015
0,
.0012
.5000
U
U
U
U
U
U
U
U
U
U UJ
UJ
UJ
UJ
UJ
UJ
UJ
UJ
UJ
UJ
.1000 U
U
U
U
JP
UJ
UJ
UJ
J
.0500 U
JP
U
J
UJ
0.
0.
0.
0.
0.
0.
0.
0.
0.
UJ
0.
0.
0.
0.
UJ
0.

0,
1000
0500
0500
0500
0500
0500
0500
1000
0500
0,
1000
1000
1000
0500
0,
5000
0,
MCL
FINAL
. 1000 U UJ
.1000 U
U
U
U
U
U
U
U
U
U
UJ
UJ
UJ
UJ
UJ
UJ
UJ
UJ
UJ
.1000 U
U
U
U
U
UJ
UJ
UJ
UJ
.0500 U
U
UJ
.5000 U
UJ









UJ




UJ

UJ
                                                 0.4
                                                      0.2
                                                 0.2
                                                    40
-------
PCB 1016
PCB 1221
PCB 1232
PCB 1242
PCB 1248
PCB 1254
PCB 1260
TOXAPHENE

1.
2.
1.
1.
1.
1.
1.
5.
Table 3
OOOOU UJ l.OOOOU UJ
OOOOU UJ 2.0000U UJ
OOOOU UJ l.OOOOU
OOOOU UJ l.OOOOU
OOOOU UJ l.OOOOU UJ
OOOOU UJ l.OOOOU UJ
OOOOU UJ l.OOOOU UJ
OOOOU UJ 5.0000U UJ
(cont'd)


UJ
UJ





TOTAL TAL METALS (ug/L)
Site ID:
Location ID:
Sample ID:
OT40
918
GP3019
SDO: 990140
Sample Data:
Depth (feet)

ALUMINUM
ANTIMONY
ARSENIC
BARIUM
BERYLLIUM
CADMIUM
CALCIUM
CHROMIUM
COBALT
COPPER
IRON
LEAD
MAGNESIUM
MANGANESE
MERCURY
NICKEL
POTASSIUM
SELENIUM
SILVER
SODIUM
THALLIUM
VANADIUM
ZINC
03/23/93
: 0.0
L V
303000 00
30.00 UN
5.40 BWN
767.00
3.70 B
5.00 U
7630 00
249.00
23.80 B
96.60
OT40
918
GP3019D
990140
03/23/93 MCL
0 . 0 FINAL
L V
135000 00
UJ 30 00 UN UJ
J 8 . 9 0 UN J
434.00 2000
1.80 B
5.00 U
6610.00
102.00 100
11.70 B
50.20 1300 i








6
50

4
5



;D
35200 00 14100 00
67.00 N J
7840.00
275.00
0.20 U
99.90
6260.00
30.00 UN
5.00 U
4740.00 B
3.00 UW
307.00
169.00
31.60 N J 15 i
5590 00
158.00
0.20 U
38.90 B 100
3430 00 B
R 30 00 UN R
5 00 U
4580 00 B
UJ 3.00 UW UJ
148.00
64.00
;f)


2


50


2


                                                                          0.5
                                                                          0.5
Notes :
(1)  -  values  listed are section levels at the Isp
                      Table 3  (cont'd)
                  DISSOLVED TAL METALS  (ug/L)
-------
Site ID:        OT40
Location ID:    918
Sample ID:      GP3019
SDO:       99087D
Sample Data:    03/23/93
Depth (feet):    0.0
OT40
918
     GP3019D
 99087D
03/23/93
0.0
 MCL     Natural Range
FINAL           Dissolved

ALUMINUM
ANTIMONY
ARSENIC
BARIUM
BERYLLIUM
CADMIUM
CALCIUM
CHROMIUM
COBALT
COPPER
IRON
LEAD
MAGNESIUM
MANGANESE
MERCURY
NICKEL
POTASSIUM
SELENIUM
SILVER
SODIUM
THALLIUM
VANADIUM
ZINC
L

30
3
58
1
5
V
85.
.00
.00
.10
.00
.00
L
20 B
U
U UJ
B
U
U
5680 00
6
9
4
514.00
2.00
3950
79
0
13
00
00
.00

UWN
.00
.70
.20
.00
1440.
3
5
4870
3
4
5.00
.00
.00
.00
.00
.00
U
U
U
U
554 00
UJ 2
B
81
U
U
00 U
U UJ
U UJ
B
UWN UJ
U
5
V

30
3
73
1
5
5710
6
9
4

.00
3980
.80
0
13

3
5
4780
4
4
.00

84
.00
.00
.60
.00
.00
00
00
00
.00


.30
U
U
B
U
U

U
U
U

UWN UJ
.00
B

B
6
UJ 50
2000
4
5
1.
100

1300
3-2.900
15 (1)


<10-
<1
<1-1
30-
<0.
-------
             primary & confirmation analysis.  Lower concentration reported.
         U - Analyte was analyzed for but not detected.
         INORGANICS
         A - The reported results are single point standard addition to comp
               B - Reported value is greater than the instrument detection 1
                   but less than the contract-required detection limit.
               E - Serial dilution not within control limits.
         N - Matrix related interference in the sample preparation procedure
               Q - Analytical spike recovery associated with sample is less
         S - Reported value was determined by the method of standard additio
         U - Analyte was analyzed for but not detected.
         W - Slight matrix related interferene is present.
         * - Sample matrix is non-homogeneous.

 Validation Flags:
         U - Analyte was analyzed for but was not detected above the reporte
             sample quantitation limit.
         J - Analyte was positively identified; the associated numerical val
             is the approximate concentration.
         R - Results are rejected due to serious deficiencies in the ability
             analyze the sample and meet quality control criteria.
             The presence or absence of the analyte cannot be verified.
         UJ - Analyte was not detected above the reported sample quantitatio
             limit.  However, the reported quantitation limit is approximate
                   or may not represent the actual limit of quantitation nee
             accurately and precisely measure the analyte in the sample.

 Note:  NT - Not tested.
dissolved fraction of ground water are compared to background
values reported for Delaware ground water and to MCLs (Table 2).
No inorganic constituents in the filtered sample exceeded the
reported natural concentration ranges in Delaware ground water or
the MCLs.  In the process of filtering,  groundwater samples are
run through a paper membrane to remove suspended soil particles.
This process imitates the natural filtering process that occurs
as ground water flows through underground sand beds.

Based upon these analytical results,  ground water quality does
not appear to be adversely impacted due to site conditions.

Sample collection at this site during 1993 was based on a
screening approach.  For this reason, detection limits for some
analytes were set above their respective MCLs.  Following this
procedure allows for more samples to be taken while still being
able to detect releases of hazardous chemicals.  If a release
is occurring from the O/W separator,  contaminant levels would
be well above MCLs and the presence of a wide range of petroleum
hydrocarbon compounds,  some of which are fairly stable in the
environment, would be present.  For example,  benzene concentration
-------
in a ground water probe sample near a leaking pipeline was found
to be 38,000,000 ug/L.  This is well above the detection limit of
10 ug/L and MCL of 5 ug/L.
Summary of Site Risks

The purpose of the Risk Assessment is to determine whether
exposure to site-related contaminants could adversely affect
human health and the environment in the event that the
contamination is not remediated.  The analysis of the "No Action"
scenario is referred to as the Baseline Risk Assessment.  The
focus of the Baseline Risk Assessment is on the possible human
health and environmental effects that could occur under current
or potential future use conditions.

Exposure pathways considered by DAFB in the Baseline Risk
Assessment include ground weter and soil.  Potential risks to
human health were identified by calculating the risk level or
hazard index (HI) for such chemicals.  The HI identifies the
potential for the most sensitive individuals to be adversely
affected by noncarcinogenic chemicals.  If the HI exceeds one
(1.0), there may be concern for potential noncarcinogenic
effects.  As a rule, the greater the value of the hazard index
above 1.0, the greater the level of concern.

Potential carcinogenic risks are identified by a risk level from
a potential exposure to a chemical for a set number of years.
For example, a risk level of 1 x 10E-6 indicates that one
additional cancer case per one million may occur.  EPA considers
carcinogenic risk level equal to or less than 1 x 10E-4, one
additional cancer case per ten thousand, as minimally acceptable.
Carcinogenic risk and HI calculations are presented in Appendix
one.

An industrial exposure scenario is used to calculate risks
associated with someone coming in contact with soils at the site.
The industrial exposure scenario assumed a worker will be exposed
to a hazardous chemical for 250 days per year for 25 years.  This
type of scenario is applicable at the site for many reasons.  The
O/W separator at Building 918 is in the industrial portion of the
base adjacent to the flight line.  Access is limited to
authorized personnel.  Additionally, DAFB is an active military
air base,  and as such, maintains a security fence around the
perimeter of the base.  This keeps the general public from
entering the base and onto the site.

Although the shallow ground water is not used for any purpose
including drinking at or near this site, a residential drinking
water exposure scenario is used to calculate risk.  This scenario
-------
is used because it is the most conservative approach and is most
protective of human health.

In the case of the O/W separator at Building 918, only trace
amounts of two pesticides  (heptachlor and lindane) were detected
in the ground water.  Each was found at a low,  estimated
concentration that did not exceed the risk based screening
concentration (RBSC).   Of the 17 metals present in the unfiltered
ground water sample, eight were also found in the filtered
sample.  None of the dissolved metals exceeded their RBSCs
(Appendix 1).   Criteria are not available for four metals that
are essential human nutrients; calcium, iron, magnesium, and
sodium.  Therefore, ground water at the site does not pose a risk
to human health.

Organic compounds present in the soil at the site were limited to
isolated occurrences of low, estimated concentrations of
1, 1, 1-TCA,  acetone,  methylene chloride, and benzoic acid in
shallow soil samples.   Only arsenic and antimony exceeded their
RBSC'a but these levels are within regional naturally occurring
ranges.  Of the 12 metals detected in soil, all of the
non-essential human nutrients were within the background range.
As with ground water at the site, criteria are not available for
calcium, iron, magnesium, and sodium which are essential human
nutrients .

Soil exposure at the O/W separator at Building 918 is associated
with a risk on the order of 10E-6 and a hazard index (HI) of
0.007.  The total risk for soil of 1 x 10E-6 is two orders of
magnitude below the EPA action level of 1 x 10E-4.  The HI for
soil of 0.007 is three orders of magnitude below the HI of 1.0
(Appendix 2).

A preliminary ecological assessment (EA)  was performed for this
and other areas at the base, and further EA studies will be
performed site-wide and will be addressed in the base-wide
investigation under a different operable unit.  The likelihood of
exposure to the soil by terrestrial wildlife at this operable
unit is slight because contaminant levels are found only in trace
amounts and are located well below grade.
Description of Alternatives

This section summarizes the three alternatives reviewed for
analysis and fulfillment of applicable or relevant and
appropriate requirements.  The selected alternatives for the O/W
separator at Building 918 include:

  Alternative 1:  No Action
-------
  Alternative 2:   Removal and Capping
  Alternative 3:   Removal, Soil Excavation, Off-Site Disposal

Alternative 1:  Pursuant to the National Oil and Hazardous
Substances Pollution Contingency Plan, 40 CFR Part 300, DAFB must
evaluate the no action alternative for the O/W separator at
Building 918 to establish a baseline for comparison to other
alternatives.  Under the no action alternative, no further
remedial action would be taken at the site.  No other
alternatives offer substantial advantages over the no action
alternative; therefore, the no action option is the preferred
alternative.  Cost for this alternative is $0.

Alternative 2:  Under this alternative, the O/W separator and
piping to the building would be removed, decontaminated, and
disposed of at an off-base facility.  Soil surrounding the
separator would be left in place.  The excavation would be
backfilled with clean soil and capped.

Decontamination of the O/W seperator and piping will require
removal of any residual liquid, sludge, and/or solid material
from within these units.  Removal of the underground piping with
the appropriate excavation equipment prior to cleanup will
facilitate decontamination activities.  Pumps, manual labor, and
other appropriate mechanical equipment will be used to clean the
piping and separator.  Steam-cleaning will then be used to
decontaminate the piping and separator.  The material removed
from these units and the solutions resulting from decontamination
procedures will be collected in tanker trucks, vacuum trucks,
55-gallon drums,  or other suitable containers prior to shipment
and off-base disposal.  Analysis of the waste materials will be
performed to determine the appropriate disposal and/or treatment
requirements for the collected material.  The O/W separator will
then be removed with the appropriate excavation equipment.  All
of the decontaminated piping and structures will then be
transported and disposed of off base at a sanitary landfill or
salvage yard.  Following backfilling of the excavation, a
composite cap consisting of a geomembrane, a drainage layer, and
a soil cover would be placed over the fill.  The surface of the
cap should slope  (1 to 3 percent) to prevent ponding of water,
and the cap should extend over the edges of the fill.

Before installing the cap system, the site would be graded and
large objects  (e.g., boulders, concrete slab fragments), if
present, would be removed; then a layer of nonwoven geotextile
fabric would be placed over the site.  This fabric layer would
protect the overlying 60-mil HOPE geomembrane,  which would serve
as an impermeable barrier over the soils, from puncturing.
A drainage layer would be placed on top of the geomembrane.  This
layer would be installed over the entire exposed cap and would
-------
drain any water that infiltrates through the soil cover.
A 2-foot thick layer of clean soil would be placed on top of the
drainage layer and seeded.  Vegetation would prevent erosion of
the soil layer, which would be graded to prevent run-on and
promote run-off.

The site would be monitored yearly to ensure contaminants left in
place are not migrating off-site.

This alternate would take approximately 4 months to implement and
cost S200,000.

Alternative 3:  Under Alternative 3, the O/W separator and piping
to the building would be removed, decontaminated, and disposed of
at an off-base facility.  Soil surrounding the separator and
piping would also be excavated and disposed of off-site.  The
resulting excavation would be backfilled with clean soil and
reseeded.

Decontamination of the O/W separator and piping would take place
as outlined under Alternative 2.

Following removal of the O/W separator and piping,  soil remaining
within the excavation would be screened using a photo-ionization
detector  (PID) and visually inspected.  Any soil with high PID
readings or that is visually contaminated will be removed and
stored in 55-gallon drums or other appropriate containers.  The
soil will be sampled and characterized for disposal.  Samples
will also be taken from the open excavation to ensure that all
contaminated soil has been removed.  The excavation would be
backfilled with clean soil and reseeded.

This alternative would take approximately 3 months to implement
and cost S258,000.
Comparative Analysis of Alternatives

This section provides an analysis of the performance of the
proposed alternatives in comparison to one another.  The proposed
alternatives are evaluated using the nine criteria as set forth
in 40 CFR Section 300.430  (e)(a)(iii)  and (f).  The nine criteria
are as follows:
  Overall protection of human health and the environment
  Compliance with Applicable or Relevant and Appropriate
Requirements (ARARs)
  Long-term effectiveness and permanence
  Reduction of toxicity, mobility, or volume
  Short-term effectiveness
  Cost
-------
  Implementability
  State acceptance and
  Community acceptance.
Overall Protection Alternatives 2 and 3 will provide an
acceptable level of protection of human health and the
environment by eliminating the principal threats through
contaminant source reduction and treatment.

Alternative 1 will also provide an acceptable level of protection
of human health and the environment since none of the detected
constituents exceeded their health based action levels.
Compliance with ARARs In RODs where the No Action alternative is
selected because action is not necessary to protect either the
public's health and welfare, or the environment, the evaluation
of ARARs is not applicable.

Long-Term Effectiveness and Permanence.   This criteria addresses
the ability of a remedy to maintain reliable protection of human
health and the environment over time once cleanup goals have been
met.

Alternatives 1, 2,  and 3 will meet the criteria for long-term
effectiveness and permanence.

Reduction in Toxicity, Mobility, or Volume Through Treatment
Alternative 1 does not reduce the toxicity, mobility,  or volume
of potential contaminants at this site.

Alternative 2 will reduce the mobility of potential contaminants
at the site by placing a cap over the soil.  The cap will stop
water infiltration and eliminate the chance of contaminants being
leached into the ground water.

Alternative 3 will reduce the toxicity, mobility, and volume of
potential contaminants through the removal of the O/W separator
and any contaminated soil at this site.
Short Term Effectiveness Alternative 1 becomes effective
immediately upon signing of the ROD for this site.  No site work
will take place, thereby eliminating any exposure of workers to
potential contaminants.
Implementability Alternative 2 will take approximately 4 months
to implement.  Alternative 3 will take approximately 3 months to
-------
implement.  Both alternatives will require soil disturbance for a
short period.  The use of personal protective equipment and air
monitoring will be required to ensure worker safety.  Alternative
1, No Action Alternative, can be implemented immediately.
Cost The cost for each alternative is as follows:

  Alternative 1:  $ 0
  Alternative 2:  $ 200,000
  Alternative 3:  $ 258,000

State Acceptance  The State of Delaware supports the Alternative
preferred in the March 1994 Proposed Plan of no further action.
Community Acceptance  Since no comments were received during the
Public Comment period, the community would appear to support the
Proposed Plan's Preferred Alternative for this action.
Selected Remedy

Based upon the above facts, DAFB and EPA decided that no further
remedial response action under CERCLA be taken at this operable
unit.  DAFB and EPA have determined through evaluation of data in
the Field Screening Report and the SI that site contaminants do
not pose any risks or threat to human health or the environment
that would warrant a remedial action.

Contaminants in the shallow ground water at the site occur in
concentrations below MCLs and below their RBSCs.  Additionally,
the shallow ground water is not currently used for drinking.
However, should this groundwater be used for drinking purposes in
the future, the risk, as discussed in the Summary of Site Risks
section, will be minimal.  The only soil contaminant that
exceeded its RBSC, arsenic, was detected within its natural range
at a depth of 10-12 feet BGS.   The low chance of exposure to soil
from this depth supports the conclusion that the soil at the site
is not a threat to human health or the environment.
Statutory/Authority Findings

The selected remedial action satisfies the remedy selection
process requirements of CERCLA and the NCP.  The selected remedy
provides protection of human health and the environment, and is
cost effective.
GLOSSARY
-------
Administrative Record:  An official compilation of documents,
data, reports, and other information that is considered important
to the status of and decisions made relative to a site.  A public
version of the record is placed in the information repository to
allow public access to the material.

Carcinogens:  Substances which can or may cause cancer.

Comprehensive Environmental Response, Compensation and Liability
Act  (CERCLA):   A federal law passed in 1980 and modified in 1988
by the Superfund Amendments and Reauthorization Act  (SARA).

Maximum Contaminant Level  (MCL):   The maximum permissible level
of a contaminant in water delivered to any user of a public water
system.  MCLs are enforceable standards.

Information Repository:  A location where copies of documents and
data related to the site are placed to allow the public access to
the material.   The IR also contains an index for the
Administrative Record.

National Priorities List:  EPA's list of the nation's top
priority hazardous waste sites.

Operable Unit:  A separate activity or portion of work undertaken
as part of a site cleanup.

Record of Decision:  A legal document that describes the final
remedial action selected for a Site, why the remedial action was
chosen, how much it will cost and how the public responded.

Risk Assessment:  A means of estimating the amount of harm which
a site could cause to human health and the environment.  The
objectives of a risk assessment are  (1)  to help determine the
need for action by estimating the harm if the site is not cleaned
up,  (2) to help determine the levels of chemicals that can remain
on the site and still protect human health and the environment,
and  (3) to provide a basis for comparing different cleanup
methods.

1, 1, 1-TCA:  1, 1,1-Trichloroethane.

Target Analyte List:  A subset of the Target Compound List which
includes only inorganic constituents.

Target Compound List  (TCL):  Developed by EPA for Superfund site
sample analytes.  The TCL in a list of analytes (34 VOCs, 65
VOCs, 19 pesticides, 7 PCBs, 23 metals and total cyanide).

Upper Confidence Limit:  The upper limit of a statistical range
with a specified probability that a given parameter lies below
it.
-------
REFERENCES
Dames and Moore, Inc./HAZWRAP, Site Investigation  for the O/W
Separator at Site 918  (MAC Code OT40), DAFB, September  1991.

Dames and Moore, Inc./HAZWRAP, Draft Field Screening Report,
Volume I, DAFB, September 1993.

Shacklette, H.T., and J.G. Boerngen, 1984.  Element
Concentrations in Soils and Other Surficial Materials of the
Conterminous United States, U.S. Geological Survey, Professional
Paper No. 1270.

Shacklette, H.T., and J.G. Boerngen, 1981.  Chemical analysis of
Soils, and Other Surficial Materials of the Conterminous United
States, U.S. Geological Survey, Open-file Report 81-197.
                             APPENDIX 1
                                                                Appendix  1

                                                       Risk - Based  Screen  o
                                                               OT40  (918)
VOCs in Soil-mg/kg

Site ID:
Location ID:
Sample ID:
Sample Date:
Depth  (feet):
RBSC
for Soil
   OT40          OT40
   B109          B110
   B109.0-2D     B110.0-2
Exceeds?     05/13/91
         OT40
         Bill
         Bill.0-2
     05/13/91
        0.0-2.0
0.0-2.0  0.0-2.0
1,1, 1-TRICHLOROETHANE
ACETONE
METHYLENE CHLORIDE
                L  V

       9.200.000    No
 10.000.000    No
         380.000    No
                                                       V
          6 BJ J
                                 L  V

                                    1 J
    12 B  J
                 27 B
SVOCs in Soil-mg/kg

Site ID:
Location ID:
Sample ID:
Sample Date:
Depth (feet):
RBSC
for Soil
   OT40
   B109
   B109.0-2
Exceeds?     05/13/91
        0.0-2.0
-------
BENZOIC ACID         410.000.000

Lead in Soil--mg/kg

Site ID:
Location ID:
Sample ID:
Sample Date:          RBSC
Depth  (feet):         for Soil
               L  V
              No
                OT40
                B109
                B109.0-2
             Exceeds?
                 OT40          OT40
                 B109          B109
                 B109.0-2D     B109.
              05/13/91     05/13/91
                     0.0-2.0
                      0.0.-2.0
             3-10

             3.0-
LEAD
                     500
                           No
               L  V
            11.50 N  J
                L  V
             17.80
0.68
                                                                      V
10.
Site ID:
Location ID:
Sample ID:
Sample Date:
Depth  (feet):
                OT40
                Bill
                Bill.8-10
                05/13/91
                8.0-10.0
                 OT40
                 B112
                 B112.0-2
                 05/13/91
                 0.0-2.0
        OT40
        B112
        B112.8-10
        05/13/91
    !.0-10.0
LEAD
                                       L   V
                                     1.10  N
                             L  V
                           3.70
                                                                      V
                       0.59
TAL Metals in Soil—mg/kg

Site ID:
Location ID:
Sample ID:
Sample Date:           RBSC
Depth  (feet):          for Soil
                                                                 Appendix 1 (

                                                                Risk - Based
                                                                      OT40 (9
                  OT40      OT40
                  918       918
                  BGP3019        BGP3019D
              Exceeds? 03/23/93  03/23/93
                            10.0-12.0 10.0-12.0
ALUMINUM
ARSENIC
BARIUM
CALCIUM
CHROMIUM
IRON
LEAD
MAGNESIUM
MANGANESE
SODIUM
VANADIUM
ZINC
    300.000
     1.6
    7200.00
      NA
     510
 NA
500
      NA
     10.000
      NA
     720
31.000
No
                                    No
L V
No
Yes
No
—
No


—
No
—
No

L

2.50



2270
3.50




3.90
V
3960
S
10.0
107
4.60
*

149
14.2
96.3
5.50
B

*
1.40
B
B
*

J
B
*
B
B


J 4280
B
11.8 B
188
6.30
3150 *
2.90
219
20.3
137
6.80
5.30
-------
                                                   Appendix 1
                                       (cont'd)
                                        Risk - Based
                                             OT40 (91
Pesticides/PCBs in Groundwater--ug/L
Site ID:
Location ID:
Sample ID:
Sample Date:
Depth (feet):
HEPTACHLOR
LINDANE
 RBSC
for Drinking
 Water
  0.00031
    0.066
                OT40
                918
               Exceeds?
                GP3019
      03/23/93
 0.0
 No
 No
                                            V
0.0015 JP J
0.0012 JP J
Total TAL Metals in Groundwater—ug/L
Site ID:
Location ID:
Sample ID:
Sample Date:
Depth (feet):
 RBSC
for Drinking
 Water
 OT40
 918
Exceeds?
      03/23/93
 0.0
     OT40
     918
  GP3019

     0.0
     GP3019D
03/23/93

ALUMINUM
ARSENIC
BARIUM
BERYLLIUM
CALCIUM
CHROMIUM
COBALT
COPPER
IRON
LEAD
MAGNESIUM
MANGANESE
NICKEL
POTASSIUM
SODIUM
VANADIUM
ZINC


11000


0
NA
18
1

NA
15
NA

73
NA
NA
26
1100
1.1
260
.02



140
—
Yes

370





L
Yes
Yes
Yes
Yes
—
Yes
Yes
Yes

67
—
Yes
Yes
—
—
Yes
Yes
V




7630
249
23.8


5

3


B
L V
303000


. 4 0 BW J
767
.70 B





6610
102

96.6
35200
. 0 N
7840


J





275
14100
31.6
5590

99.9
6260
4740
307
169

B






3430

148
64.0

135000
8.90 BN J
434
1.80 B


11.7 B
50.2

N J

158
38.9 B
B
4580 B


Dissolved TAL Metals in Groundwater--ug/L

Site ID:                               OT40
                                                                Appendix 1  (
                                                              Risk - Based S
                                                                       OT40
                                 OT40
-------
Location ID:
Sample ID:
Sample Date:
Depth (feet) :

ALUMINUM
BARIUM
CALCIUM
IRON
MAGNESIUM
MANGANESE
SODIUM
ZINC
918
RBSC Exceeds?
for Drinking
Water 0.0
L V
11000 No
260 No
NA
NA — 514
NA
370 No
NA
1100 No
918
GP3019
03/23/93
0.0
L V
8.52 B
58.1 B
5680
544
3950 B
79.7
4870 B
5.8

GP3019D
03/23/93

84.3 B
73.6 B
5710

3980 B
81.8
4780 B
B
                                     APPENDIX 2
                            Appendix 2
                      OT40  (918) Calculated Risks  and  Hazards
OT40 (918)

Soil (mg/kg):
    Arsenic
                   RBSC for       RBSC  for
                   EPC     1E-06 Risk      Hazard  I
1 6E 00        3 IE 02

        Total Risk:  IE 06
Groundwater:
     No constituents of concern
                                  Site Related
                                       Risk
        IE 06

 HI:  7E 03


OE 00
                                             OE 00
-------