United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROCVR06-90/059
September! 990
Superfund
Record of Decision:
Tenth Street Dump/Junkyard, OK
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50272-101
I REPORT DOCUMENTATION i. REPORT NO. «
1 PAGE EPA/ROD/R06-90/059
1 4. TMcwdSuMM*
L SUPERFUND RECORD OF DECISION
P Tenth Street Dump /Junkyard, OK
1 First Remedial Action - Final
7. AiMhorM
12. Sponw>ringOrg*nlallefiN«mMdAddraM
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
8. ntclfitHet AiBiMlon Mo.
f. R*portM>
09/27/90
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14.
IS. SupBtonwitey NOIM
16. Abstract (Unit: 200 word*)
The 3.5-acre Tenth Street Dump/ Junkyard site is an inactive landfill in Oklahoma City,
Oklahoma, within the North Canadian River's 100-year floodplain. There are two
residences and a salvage yard within 100 yards of the site. From 1951 to 1979, the
site was used, in succession, as a municipal landfill, a privately owned and operated
salvage yard, and an automobile salvage yard. Waste materials accepted by the first
salvage yard included paint thinners, old transformers, and tires. Dielectric fluid
that contained PCBs was drained from old transformers, stored in barrels, and sold.
During this PCB recovery process, substantial quantities of PCB-contaminated oil were
spilled onto the ground at the site. In 1983, EPA site inspections located 20 drums,
some of which were corroded and leaking contaminated material into the soil. Soil
samples, taken on and around the site, showed contamination by hazardous materials,
particularly, high levels of PCBs. In 1985, EPA completed removal actions, which
included disposal of drums containing hazardous waste, decontamination and relocation
of junk automobiles, consolidation of contaminated soil to the center of the site,
installation of a plastic liner and a clay cap, and installation of security fencing.
This Record of Decision addresses soil contamination at the site. It is estimated
(See Attached Page)
17. Document Analytic «. DmcriptOf*
Record of Decision - Tenth Street Dump/Junkyard, OK
First Remedial Action - Final
Contaminated Medium: soil
Key Contaminants: organics (PCBs)
b. kfcnWm/OpMi-EnaM Term
c. COSATI FMdQroup
IB. AviUibMty Statement
1*. Security d*M(TM*R»par1)
None
20. Security Ct*M(TMeP»ge)
None
21. NaotPegM
74
22. Me*
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EPA/ROD/R06-90/059
Tenth Street Dump/Junkyard, OK
First Remedial Action - Final
Abstract (Continued)
that 8,500 cubic yards of soil are contaminated by PCBs, with 7,500 cubic yards of this
total having PCBs levels above the TSCA PCB spill cleanup policy level of 25 mg/kg. The
primary contaminants of concern affecting the soil are organics including PCBs.
The selected remedial action for this site includes removing the red clay cover and
plastic liner; excavating an estimated 7,500 cubic yards of PCB-contaminated soil with
concentrations of 25 mg/kg and higher, followed by treatment of the excavated soil by
chemical dechlorination and carbon adsorption to control air emissions; and backfilling
and regrading the excavated area with clean and treated soil. The estimated present
worth cost for this remedial action is $4,044,000. There are no O&M costs associated
with this remedial action.
PERFORMANCE STANDARDS OR GOALS: Contaminated soil with greater than 300 mg/kg PCB (an
order of magnitude higher than the health-based goal) is considered the principal
threat. However, the soil excavation goal is PCB 25 mg/kg (TSCA), due to the cost
effectiveness of treating soil with low levels of PCBs along with the highly
contaminated soil, and is based on a 10-6 excess cancer risk level. Soil residuals will
contain less than 2 mg/kg PCBs.
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DECLARATION
TENTH STREET DUMP
RECORD OF DECISION
SEPTEMBER 1990
Statutory Preference for Treatment as a
Principal Element is Met
and a Five-Year Review is not Required
SITE NAME AND LOCATION
Tenth Street Superfund Site
3200 NE Tentn Street
Oklahoma City, Oklahoma
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for the
Tenth Street Site in Oklahoma City, Oklahoma, which was chosen in accordance
with the Comprehensive Environmental Response, Compensation and Liabilityj
Act of 1980 (CERCLA), as amended by the Superfund Amendments and '
Reauthonzation Act of 1986 (SARA), and, to the extent practicable, f
the National Oil and Hazardous Substances Pollution Contingency Plan
(NCP). This decision is based on the administrative record for this
site.
The State of Oklahoma does not support the selected remedy.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from tftis site, if
not addressed by implementing the response action selected in the Record
of Decision (ROD), may present a potential endangerment to public health,
welfare, or the environment.
DESCRIPTION OF THE SELECTED REMEDY
The selected remedy addresses the principal threat posed by the site
through chemical treatment of PCB contaminated soil at the site. Treated
soil will be disposed on sue to backfill the excavated area.
The major components of the selected remedy include:
Remove the existing red clay cover and the visqueen plastic
liner.
Excavate an estimated 7,500 cu. yd. of PCB contaminated soil with
concentrations of 25 ppm and higher.
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Chemically treat the excavated contaminated soil by a chemical
dechlor"'nation process meeting the Toxic Substance Control Act (TSCA^
PCB alternative treatment requirements.
Backfill the treated soil ir, the excavated area.
Grade the site for effective drainage and establish vegetative cover.
SWUTQRY DETERMINATIONS
The selected remedy is protective of human health and the environment,
compiles with federal and state requirements that are legally applicable
or relevant ana appropriate to the remedial action, and is cost effective.
This remedy utilizes permanent solutions and an alternative treatment
technology to the maximum extent practicable and satisfies the statutory
preference for remedies that employ treatment that reduces toxicity,
mobility, or volume as a principal element.
Because this remedy will not result in hazardous substances remaining
onsite above health-based levels, the five-year review will not app"«y
to this action. (
Robert E. Laytor,/Or. ,^P. E. Date
Regional Administrator
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I. LOCATION AND INSCRIPTION
The Tenth Street Site (the "site"] is located at 3200 NE Tenth Street, in
the far eastern boundary of Oklahoma City, Oklahoma (Section 31, Township
12 North, Range 2 West, of Oklahoma County). The site is approximately
3.5 acres in size. It is situated immediately south of NE Tenth Street
and lies between Bryant Avenue and the North Canadian River. Standish
Avenue, a side street east of Bryant, is the North-South street closest
to the western boundary of the site (see Figures 1 & 2). The site is
also situated in the 100-year flood plain of the North Canadian River.
The area in the vicinity of tne site is used primarily for industrial
purposes.
Vegetation in the area is directly related to tne North Canadian River
and to the degree of urbanization. It consists of marsh grass and willow
and cottonwood trees along the river banks. Grasscovered fields and lots
away from the river are punctuated by varieties of elm, backjack, post
oak and other deciduous trees. Around the site are primarily short grasses
while the site itself is covered by a tall grass.
Within 100 yards of the western sue boundary is a residence. East of |
the site about 75 yards is a residence and a salvage yard (Figure 2). 1
Two individuals live at the residence adjacent to the salvage yard and I
one individual lives at the residence west of the site. There are about
30 visitors per day at the salvage yards and about 4 visitors per day at
the home west of tne site.
According to a 1985 traffic count, approximately 16,000 cars per day pass
the site on the NE Tenth Street. The closest population centers are
Oklahoma City (446,120, 1986 census records) and Del City (28,523, 1980
census records).
The Oklahoma City public water supply source is Draper Lake. Del City
uses surface water from Thunderbird Lake and ground water for its sources
of drinking water. Both Draper Lake and Thunderbird Lake are outside of
a three-mile radius of the site. Water supply for about 29,218 people
within a three-mile radius of the site is provided by ground water from
the Garber-Wel1ington formation.
The nearest major surface water body is the North Canadian River, which
lies south and east of the site. Regional drainage is toward the river
but local topography causes some variations in this pattern. Two southeast
trending tributaries about 200 to 400 yards west of the site become confluent
and join the North Canadian River about 400 yards south of the site.
About 0.25 mile to the northeast of the site are two large ponds which
were previously quarrying pits for sand and gravel.
The sit? rests on unconsolidated Quarternary alluvium deposits of the
North Canadian River (Figure 3); its thickness ranges from a few inches
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TENTH STREET SUPERFUNO SITE
OKLAHOMA CITY, OKLAHOMA
GEOLOGIC MAP (WOOD & BURTON, 1968)
FIGURE 3
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The site rests on unconsolidated Quaternary alluvium deposits of the
North Canadian River (Figure 3); its thickness ranges from a few inches
up to 100 feet. Beneath the site, the alluvium is about 30 feet thick.
The Garber-Uellington Formation underlies the alluvium with the Hennessey
shale stratigraphically positioned in between. However, the Hennessey
shale is not present underneath the site.
The Garber-Uel1ington is the most important source of ground water in the
Oklahoma City-Del City-Midwest City area. In the vicinity of the site,
the base of fresh water is sloped from 600 to 300 feet above sea level.
The Hennessey shale is not a significant aquifer but the water is of
sufficient yield and quality to provide water supplies for domestic and
agricultural use (ground water classification 28).
Ground water beneath the site is present in at least two distinct zones
as indicated by field investigations and water quality data. A shallow
water-bearing zone exists from 6 feet to at least 30 feet below ground
surface (BGS). The water table ranges from 6 to 10 feet BGS and slopes
gently to the south-southeast, towards the North Canadian River (Figure
4). Another zone is present at about 160 feet BGS. The upper and lower
bounds of this deeper zone are not known. Nor is it known if other water
bearing units exist between these shallow and deep zones.
II. SITE HISTORY AND ENFORCEMENT ACTIVITIES
Evidence from aerial photographs indicate that the area was operated as a
municipal landfill between 1951 and 1954. From about 1959 to 1979
Mr. Raymond Cobb leased this site and operated it as a salvage yard
until his death in 1979. During his operation, materials such as paint
thinners, tires, and old transformers were accepted in the salvage yard.
Dielectric fluid that contained polychlorinated biphenyls (PCBs) was
drained from old transformers, stored in barrels, and sold. During the
recovery process, substantial quantities of oil were spilled onto.the
ground. After Mr. Cobb's death, Mr. Rolling Fullbnght operated the site
as an automobile salvage yard called Deadeye's Salvage Yard.
In 1983, the Field Investigation Team of the Environmental Protection
Agency (EPA) inspected the site and observed about 20 drums, some of
which were corroded, leaking, or bulging. Liquids contained in the drums
and soils from the surrounding area were sampled by FIT. High concentrations
of volatile organic compounds, benzene, polynuclear aromatics, methylene
chloride, methylene phenol, ethanol, tetrachloroethane, acetone, and
tetrachloroethylene were detected in soil. Subsequent sampling in 1984
and 1985 by the the Technical Assistant Team (TAT) of EPA detected high
concentrations of PCBs in the soil on and around the site.
In August 1985, the EPA Region 6 Regional Administrator approved an
emergency response action to remove and dispose of electrical equipment
and drums containing hazardous substances. This authority also included
actions to decontaminate and relocate junk automobiles, consolidate
contaminated soils to the center of the site, grade the site for effec-
tive drainage, install a synthetic liner and clay cap, and erect a
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a security fence around the site.
After completion of the removal action, the site was evaluated under the
criteria for"determining priorities among releases or threatened releases
throughout the United States for the purpose of taking remedial action.
In January 1987, the site was proposed ^or inclusion on the National
Priorities List (NPL) due to the potential for ground water contamination.
The site was placed on the NPL in July 1987.
A remedial investigation and feasibility study (RI/FS) was conducted by
EPA Region 6 in Spring 1989 to identify the types, quantities and locations
of contaminants, to identify the risk from these contaminants and to
address the contamination problems. The RI consisted of a comprehensive
field sampling and analysis program followed by validation and evaluation
of the data collected. The RI report was finalized and released to the
public in March 1990.
The results of the RI identify that:
o PCBs are the contaminants of concern at the site, based on concentration
and risk; the predominant PCB species present is Aroclor 1260;
o Contamination is limited to soil at the site; and
o Ground water or surface water contamination was not I
detected. '
The Feasibility Study Report and Risk Assessment Report for this site
were completed in July 1990. In August 1990, the FS report and the Risk
Assessment report were released to the public along with the Proposed
Plan. A 30-day public comment period was provided, ending on
September 3, 1990.
Searches for potentially responsible parties (PRPs) have been conducted
and two possible PRPs, Mr. Sullivan Scott and Mr. Elmer Cobb, were identified.
Upon further investigation, other PRPs may be identified. The known PRPs
were notified in waiting on March 23, 1989 via a general notice letter
and given the opportunity to conduct the RI/FS under the supervision of
EPA. However, neither has elected to undertake these activities.
III. HIGHLIGHTS OF COMMUNITY PARTICIPATION
A Community Relations Plan for the site was developed and finalized in
June 1989. This document lists contacts and interested parties throughout
government and the local community, and locations for information repositories,
It also establishes communication pathways to ensure timely dissemination
of pertinent information. Fact sheets outlining the RI and its progress
were distributed. An open house to provide information on the RI activities
was held in September 1989. The RI report was released to the public in
March 1990. The FS Report, Risk Assessment Report, and the Proposed Plan
were released to the public in August 1990. An open house to provide
information on the FS and the Proposed Plan was held on August 7, 1990.
All of these documents were made available in the administrative record ana
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information repositories maintained at the Oklahoma City Public Works
Department, Oklahoma State Department of Health, and the Ralph Ellison
Library. *\ public comment period was held *rom August 9, 1990 to
September 7, 1990. 4 public meeting was held or, August 14, 1990 to present
the results of the RI/FS and the preferred alternative as presented in
the proposed plan for the site. All comments which were received by EPA
within the comment period, including those expressed verbally at the
public meeting, are addressed in the responsiveness summary section of
the Record of Decision.
IV. SCOPE AND ROLE OF RESPONSE ACTION WITHIN SITE STRATEGY
As characterized by the RI , the problems at the Tenth Street Superfund
Site are limited to soil contamination. The site was determined to pose
a principal threat because of the potential for direct contact with the
contaminated soil and the soil's potential impact on ground water. The
scope of the response action is to address the principal threat at the
site by preventing current or future exposure to the contaminated soil
through treatment and/or containment, and reducing or controlling the
potential migration of contaminants from the soil to ground water.
SUMMARY OF SITE CHARACTERISTICS
Analyses of soil, ground water, and surface water from the site and
adjacent areas indicate contaminants at the site are primarily related to
PCBs. Other contaminants do not pose a health risk, based on the risk
assessment. Contamination is limited to soil at the site.
Soil
Soil samples were collected at selected intervals during the drilling of
five ground water monitoring wells and 26 shallow boring; of these 31
locations, two monitoring wells and 11 shallow borings are offsite (Figure
5). A summary of the PCB soil sampling results is listed in Table 1.
The concentrations of PCBs range from 41 ppm to as much as 1700 ppm,
while the average concentration is 110 ppm. Figure 6 shows total *\roclor
concentrations without species differentiation.
Laterally, PCBs are generally located more towards the central portion of
the site. Vertically, PCBs are present from 1 ft to as much as 8 n
below the ground surface (including the thickness of the cap}. Excluding
the cap, the maximum depth of contamination or thickness of contaminated
soil below the protective cap is about 6.7 ft. In general, contaminated
soil is about 1 foot thick at the cap periphery, while it is between 3 to
6.7 ft thick towards the center of the cap. The increase in the thickness
of contaminated soil from 2 feet in 1985 to 6.7 feet in 1989 (Figure 7),
is due to grading of soil towards the center of the site during construction
of the protective cap. Contamination greater than the 25 ppm PCB remedial
goal was r,ot detected at depths greater than 6 feet. The deepest point
where contamination was detected is about 3 ft above the ground water
table.
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During preparation of the feasibility study report, review of the 1985
Removal After-Action Report revealed that PCB contamination was detected
in the roao rjght-of-way at a depth approximately^ ft. and the protective
cap was extended to the edge of the NE Tenth Street. This area of
contamination is between the north fence line of the site and the edge of
the NE Tenth Street. Additional sampling is planned and results will be
used to estimate the additional volume of contaminated soil to be addressed
in the remedial action.
Only local concentrations of polyr.uclear aromatic hydrocarbons (PAHs)
were detected (Tables 2 - 8). The levels are slightly elevated and are
consistently associated with burned rubble and landfill debris. The
samples in which DAHs were detected contained burned wood, tires, and
other debris typical of landfills.
Lead concentrations are slightly elevated in onsite areas but are within
normal ranges in the offsite areas. The slightly elevated concentrations
of lead are typically associated with salvage activities. Lead at the
Tenth Street Site is most likely a result of automobile and other metal
salvage decomposition and corrosion.
Based on the results of soil sampling, it is estimated that approximately
7,500 cu. yd. of soii contaminated with PCBs greater than 25 ppm are f
present at the site. Of this volume, 6,500 cu. yds. are contaminated j
with greater than 300 ppm PCBs, representing the volume of material that I
poses the principal threat at this site. Principal threats are defined
as soil contaminated an order of magnitude or more above the health-based
goal set for the site. Soil contaminated between 25 ppm and 300 ppm'
(1,000 yds.) represents the low-level threat posed by the Tenth Street
site.
Ground Water
Ground water samples were collected from the five monitoring wells installed
during the RI and from one existing private well. Locations of ground
water samples are shown in Figure 8. PCBs or compounds that may act as
carriers for PCBs were not detected in ground water samples collected
(Tables 9 and 10).
The ground water table at the site ranges from about 1151.7 MSL (Mean Sea
Level) to about 1150.0 MSL. Contaminated soil at its deepest point onsite
is approximately 3 feet above the water table. The ground water was
measured in April 1989, a month in which ground water levels are considered
to be high in Oklahoma.
Surface Water
Surface water samples were collected from a tributary that runs by the
western margin of the Site and from the North Canadian River (Figure 9).
Contaminants attributable to the site were not detected in the surface
water samples collected (Table 9 and 11). This conclusion is based on
upstream samples being equally or more contaminated than downstream samples.
17
-------
Table 2
Organic chemicals detected in soil from the
on-site area at the 10th Street site
Range of
Chemical
Acenaphtene
Acetone
Anthracene
Aroclor 1242
Aroclor 1254
Aroclor 1260
Benzene
Benzo(a)
anthracene
Benzo(a)
pyrene
Benzo(b)
fluoranthene
Benzo(g,h,i)
perylene
Benzo(k)
fluorathene
Bis(2-etnylhexy1]
pnthalate
Carbon disulfide
Chloroform
Chloromethane
Chrysene
Di-n-butyl-
phthalate
Frequency
3/20
15/20
7/20
1/20
4/20
16/20
3/20
13/20
16/20
17/20
11/20
12/20
17/20
3/20
7/20
3/20
18/20
5/20
Average
65 R
13
160 R
27,000
40,000
180,000
3
630
580
750
510
850
1200
3
0.6 R
2
480
410
Upper
Bound
83
35
260
170,000
100,000
940,000
3
2200
1900
2700
1200
3000
5800
6
2
2
1500
460
Range of
Detections
47-83
5-47
48-260
230,000
290-100,000
270-1,700,000
0.2-3
110-2800
100-2500
150-4300
57-1200
80-4300
170-9900
0.9-6
0.2-2.0
0.6-0.9
15-2400
49-460
Quantitation
Limits
380-4300
12-13
380-4300
92-490,000
180-970,000
180-200
6
380-4300
380-4300
380-850
380-4300
380-4300
380-420
6
6
11-13
380-410
380-4300
18
-------
Table 2 (continued)
Ch_f , 1
Diben2o(a,h)
anthracene
DDT
Fluoranthene
Fluorene
Indeno(l,2,3-cd)
pyrene
Phenanthrene
Pyrene
Tetrachloro-
ethylene
Toluene
1,2,4-
Trichloro-
benzene
1,1,1-
Trlchloroetnane
Xylene
Frequency
7/20
3/20
17/20
3/20
12/20
16/20
16/20
3/20
6/20
5/20
3/20
5/20
Average
410
100
650
50
490
460
620
3
2
400
3
4
Upper
Bound
530
162
2100
68
1100
1400
1900
5
3
1400
3
12
Range of
Detections
41-530
44-162
96-3000
34-68
44-1100
90-1400
130-2200
3-7
0.2-3
52-1400
0.3-0.4
2-22
Range of
Quantitation
Limits
380-4300
19-49,000
380-440
380-4300
400-4300
380-4300
380-4300
6
1
6 t
f
380-4100
6
6
R = Recalculated using only detected quantities of contaminant;
19
-------
I
1
i
1
i
f
£
i
*
^j»
ii
d
d
m
1 W fcS 1 «» J
Chemical
Acenaphtene
Acetone
Anthracene
Aroclor 1242
Benzo(a)
anthracene
Benzo(a)
pyrene
Benzo(b)
fluoranthene
Benzo(g,h,i)
perylene
Benzo(k)
fluorathene
Bis(2-ethylnexyl)
phthalate
Chrysene
Dibenzo(a.h)
anthracene
Fluoranthene
".ndeno(l,2,3-cd)
pyrene
Phenanthrene
Pyrene
W I ^ W 1 1 '
-------
Table 4
Oraanic chemicals detected in soil from the off-site
area at the 10th Street Site
r.hemical
Acenaohthene
Acetone
Anthracene
Aroclor 1260
Benzo(a)
anthracene
Benzofa)
oyrene
Benzo(b)
Fluoranthene
Benzo fo,n,i)
oerylene
Benzo fk)
fluoranthene
Bisf'-ethylhexyl
ohthalate
Chrysene
Fluoranthene
lndeno'l.?.i-c
-------
Table 5
ound levels
Chemical
Aluminum
Antimony
Arsenic
Barium
Beryl I1um
Cadmium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Nickel
Potassium
Selenium
Silver
Sodium
Thallium
Vanadium
Zinc
Cyanide
Cn-Site
11000
12
13
570
0.29
9.7
27000
55.5
10.3
708
57500
1100
3450
480
0.22
50.7
1990
0.47
1.7
342
0.28
27.7
2170
1.3
Salvaqe Yarn n** <-..
10400
8
15.9
472
Ooo
C.C.
5.0
61000
66.5
12.5
400
65100
769
3930
581
0 67
v» O/
49.9
1740
nd
nd
2530
nd
34.2
1790
nd
7170
4.2
2f
.6
247 "
0.32
1 Q
* y
15300
1 1
13
5.0
w \j
50.6
10400
289
2430
219
0.071
9n
.8
1160
nd
nrl
'lu
80.1
nd
18.1
289
0.8
e Loc :
^"^""^ --«.
<20000
<300
>2
<30000
50
vIC
>15
20
>30,000
>20
<3000
>500
-
>20
<10000
<5000
<50
>5400
1 Rational a
66000
6b
554
1
0.6C
24000
53
10
!
25000
20
9200
560
0.3d
?n
£U
23000
Or
.5
0 Q5e
w . U3
12000 .
5f
76
54
1
1
1
1
1
tl
1
1
1
|
^B
1
|
V
I
-------
1
1 Table 6
l»
(Chemical
Aluminum
Antimony
Arsenic
Barium
Beryllium
Cadmium
Calcium
Chromium
Cobalt
^ Copper
^^ Iron
I Lead
Magnesium
Manganese
Mercury
Nickel
1 Potassium
Selenium
Silver
Sodium
Thallium
1 Vanadium
Zinc
Cyanide
Inorgani
area at
Frequency
20/20
10/20
20/20
20/20
11/20
18/20
20/20
20/20
19/20
20/20
20/20
20/20
20/20
20/20
14/20
20/20
20/20
7/20
6/20 ]
20/20
2/20
20/20
20/20
8/20
c chemicals detected in soil from
the 10th Street site
Averac
11000
12
13
570
0.29
9.7
27,000
55.5
10.3
708
57500
1100
3450
480
0.22
50.7
1990
0.47
1.7
342
0.28
27.7
2170
1.3
Upper Range of
[e Br-md Detections
180000 2990-19000
43 9.3-61.9
30 1.4-35.8
1120 43.1-1120
0.62 0.12-0.62
24 0.9-27.5
44,200 2700-44,200
120 4.7-120
24.5 2.7-32.4
3190 12.6-5560
155000 3740-223000
3610 4.1-5620
5360 1760-5810
906 89-938
0.52 0.13-0.52
88.8 5.2-88.8
3300 640-3300
0.59 0.35-0.59
6.5 1.4-9.9
606 67.6-606
0.46 0.4-0.65
48.4 6.8-57.9
5330 120-6730
3.1 0.64-4.3
the on-site
Range of
Quant.
Limits
5.3-9.2
.
0.27-0.57
0.72-0.88
.
7.4
.
0.09-0.12
0.3-4.2
0.9-1.0
_
0.03-0.59
.
1.1-3.9
23
-------
Table
Chemical
Aluminum
Antimony
Arsenic
Barium
Beryllium
Cadmium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Nickel
Potassium
Selenium
Silver
Sodium
Thallium
Vanadium
Zinc
Cyanide
»
Frequency
4/4
2/4
3/4
4/4
1/4
3/4
4/4
4/4
4/4
4/4
4/4
4/4
4/4
4/4
2/4
4/4
4/4
0/4
0/4
3/4
0/4
4/4
4/4
0/4
Averai
10400
8.0
15.9
472
0.22
5.0
61100
66.5
12.5
400
65100
769
3930
581
0.67
49.9
1740
2530
34.2
1790
Upper
:)e Bound
14900
15.5
27
776
0.37
9.1
149000
136
26.8
893
165000
1250
6310
994
2
111
2410
"
9040
"
56.4
3110
Range of
Detections
6000-14900
9.7-15.5
15.8-27
145-776
0.37
3.6-9.1
5220-14900
9-136
3-26.8
9.3-893
6580-165000
2.6-1250
2040-6310
162-994
0.55-2.0
6.7-111
1110-2410
-
-
494-9040
-
14.1-56.4
37.2-3110
Range of
Quant.
Limits
6.5-7.2
1.3
0.32-0.35
0.85
0.72-0.83
0.87-1.0
39.8
0.43-0.57
n « « **
1.1-1.2
24
-------
Table 8
Inorganic chemicals detected in soil from
the off-site area at the 10th Street site
Chemical
Aluminum
Antimony
Arsenic
Barium
Beryllium
Cadmium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Nickel
Potassium
Salenium
Silver
Sodium
Thallium
Vanadium
Zinc
Cyanide
Frequency
7/7
1/7
6/7
7/7
2/7
2/7
7/7
7/7
7/7
7/7
7/7
7/7
7/7
7/7
1/7
7/7
7/7
0/7
0/7
6/7
0/7
7/7
7/7
1/7
Average
7170
4.2
2.6
247
0.32
1.9
15300
13
5.0
50.6
10400
289
2430
219
0.071
9.8
1160
-
-
80.1
-
18.1
289
0.8
Upper
Bound
16300
7.4
5.4
402
.09
6.9
42200
25.7
8.9
207
17900
917
5160
332
0.14
18.1
2750
-
-
139
-
34.9
741
2.0
Range of
Detections
2880-18000
8
1.4-5.8
53.1-402
0.36-1.0
3.4-7.6
6510-47200
4.5-25.7
2.7-9.0
3.1-219
4620-17900
6.4-917
1250-5670
105-332
0.16
5.3-18.1
442-3040
-
-
48.9-139
-
10.7-37.8
21-741
2.2
Range of
Quant.
Limits
6.6-7.5
2.7
0.32-0.34
0.83-0.98
_
..
0.11-0.12
_
0.73-0.83
0.89-1.0
.
0.43-0.49
1.1-1.2
25
-------
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r" O »r- IQ
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ocecc c cc Q j^ EE
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-------
Table 10
Tnorgam'c chemicals detected in around water
from the 10th Street Site.
Chemical
Aluminum
Arsenic
Barium
Beryllium
Chromium
Cobalt
Coooer
Lead
Manganese
Nickel
Selenium
Vanadium
7inc
Private Well
?7.4 c
'2.2) d
'51
(l.«rt
U.6)
'7.6)
89.'
(I.?)
n.i)
(17.8)
ri.4^
6.5
1.62
UDorade3
9190
9.7
190 .
t
0.1
5.8
7.7
7.1
9.8
924
12.5
'l.D
?0.9
44.5
Downorade"
6630
4.-?
232
0.1
10.9
7.Q
5.4
6.2
1690
7.Q
1.0
17.1
10.8
a = Arithmatic average of monitoring wells f1W-lS and f1W-?S.
b = Arithmatic average of monitoring wells HW-1S, MW-4S and f1W-40.
c * AH concentration in ug/1.
d = Detection limit within brackets.
D s Proposed limit.
s * Secondary limit (Taste and aesthetic quality}.
Maximun
Concentration
Limits
"50 PS
50 (30 P)
5000 P
100 P
1000 S
50 f5 P) !
50 S '
50 P
5000 S
ll
I
I
1
l
28
-------
7?3
T3
OKLA
HOMAC
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itr
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rf
3200 N.E. TENTH STREET
OKLAHOMA CITY, OKLAHOMA
^«3- *
L«i»5**i>.
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PARK >
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15
J^T
LCITY
OS
J TEK STREET SUPERFUND SITE
Slr CE WATER SAMPLING LOCATIONS
FIG; c ^ sw'1 Surface water-1
-------
Table 11
Inorganic chemicals detected in surface water
from the 10th Street Site,
Chemical
Upstream
Downstream
Aluminum
Arsenic
Barium
Calcium
Copper
Iron
Lead
Magnesium
Manganese
Potasium
Selenium
Sodium
Vanadium
Zinc
1080
(2.2) a
152
159000
(2.9)
2250
21.4
30400
1280
7160
(3.4)
106000
(4.9)
68.4
1630
5.2
154
99300
29
7760
1.7
41000
141
5900
3.7
151000
9.3
113
a = Detection limit within brackets.
+ = Hardness dependent (100 mg/L assumed).
, Quality Criteria
Acute Chronic
360
190
82+
12+
1000
3.2+
280
35
120+
110+
30
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Migration Pathways
The containnarfts of concern at this site are PCBs. " The migration of
PCBs in the subsurface (in soil, soil to ground water, and in ground
water) is controlled by several factors. These include the solubility of
PCBs, soil permeability, the presence or absence of transport-facilitating
solvents, organic carbon content, and organic colloids. With the very
low solubility of PCBs, the presence of a protective cap, the absence of
transport-facilitating solvents, normal organic carbon content, no detection
of PCBs adhering to colloids, as well as the physical separation between
contaminated soil and the ground water table, it would take free product
to be present at the site in order for subsurface migration to occur.
PCBs are fixed in the soil matrix beneath the Tenth Street site and migration
is not occurring.
At present time, airborne migration of PCBs from the site is not likely.
With the protective soil cover and vegetation established, any migration
of contaminants by particulates generated from wind erosion is virtually
eliminated. The potential for airborne migration of PCBs from the. site
would exist, only if the soil cover is destroyed by external forces such
as heavy erosion, flooding, or physical destruction. Likewise, the current
potential for transport of PCBs from the site via surface water is minimaJ
due to the existence of the protective cover. !
If the PCB contaminated soil was exposed, the areas most likely to be
impacted by contaminant migration would be the nearby community and persons
who visit the automobile junk yard.
VI. SUMMARY OF SITE RISKS
A baseline risk assessment was conducted for this site and is presented in
a document entitled, Baseline Risk Assessment for the Tenth Street Dump
Superfund Site, Oklahoma City, Oklahoma. The assessment follows procedures
set in the EPA Risk Assessment Guidance for Superfund Sites, December 1989.
Identification of Contaminants of Concern
Chemicals whose analytical results are of acceptible quality for use in
the risk assessment and related to the site were identified as contaminants
of concern for this site. Concentrations of site-related contaminants in
water and soil samples are compared to applicable or relevant and appropriate
requirements (ARARs). In addition, comparisons are made to local and
national background conditions. Chemicals whose concentrations are less
than background are eliminated from the quantitative risk assessment.
Chemicals detected at the site and their comparison to ARARs and background
levels are also summarized in Tables 5, 10, and 11.
Exposure Assessment
In the risk assessment, EPA evaluated the current, or baseline, risk to
health posed by the contaminants at the Tenth Street site. Since the site
is currently unoccupied, assumptions regarding the most probable future
land use for the site were made by EPA. Because the properties surrounding
the site are operating automobile salvage yards and inquiries have been
made of EPA regarding the suitability of the site for future development,
EPA considered the probable future land use to be commercial. The risk
31
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assessment and the development of remedial goals focused on the effects
workers exposed to the site contaminants.
The assumptions used for the ground water ingestion scenario are:
1. 70-year lifetime;
2. 70 kg. (adult) and 10 kg. (child) body weight;
3. ingestion rate of 2 liters per day for adults;
4. ingestion rate of 1 liter per day for children.
The assumptions used for soil ingestion and dermal absorption
were based or, an industrial/ commercial exposure scenario:
1. 70-year lifetime;
2. 70 kg. body weight;
3. ingestion rate of 0.1 grams per day;
4. exposure duration of 9 years, 40 hours per day,
five days per week.
These assumptions are standardized in the risk assessment guidance.
Toxicity Assessment
Quantitative risk assessment requires contaminant-specific qualitative '
and quantitative toxicity information. Contaminants are classified as |
systemic toxicants, and/or as known or suspected human carcinogens. For
systemic toxicants, the EPA reference doses (RfDs) and, acceptable intakes
subchronic and chronic (AISs and AICs) are identified. For known or
suspected carcinogens, EPA weioht-ofevidence classifications and upper
bound cancer slope factors are identified. Included in the risk assessment
are pertinent standards, criteria and guidelines developed for the protection
of human health and the environment. Dose-response parameters used in
the assessment are presented below.
Organic Chemicals
Acetone. The chronic oral RfD for acetone is 0.1 mg/kg/day (Health
Effects Assessment Summary Tables, Third Quarter FY 1989. (HEAST).
Benzene. The chronic oral RfD for benzene is 7E-4 mg/kg/day (0.0007)
(ATSDR 1987). Benzene is classified as a human carcinogen (Group A), and
has an oral and inhalation slope factor of 2.9E-2 (mg/kg/day)" (IRIS
and HEAST). Some individuals exposed to benzene over a long period of
time have developed leukemia (cancer of the white-blood-cell forming tissue)
(ATSDR 1987).
Bis (2-ethylhexyl) phthalate. The chronic oral RfD for bis (2ethyl hexyl)
phthalate is 2E>2 mg/kg/day (Integrated Risk Information System (IRIS)
and HEAST). It is classified as a probable human carcinogen (Group B2)
and has an oral slope factor of 1.4E-2 (mg/kg/day)"" (HEAST).
Carbon disulride. The chronic oral RfD for carbon disulfide is 0.1 mg/kg/day
(IRIS).
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Chloroform. Tne subchronic and cnromc oral RfD for chloroform Is 1E-2
mg/kg/day (HEAST and IRIS). Chloroform is classified as a probable human
carcinogen (Group B2), and has oral and inhalation slope factors of 6.1E-3
and 8.1E-2 (mg/kg/day) , respectively (IRIS).
Chloromethane. Chloromethane is classified as a possible human carcinogen
(Group C), and has oral and inhalation slope factors of 1.3E-2 and 6.3E-3
(mg/kg/day), respectively (HEAST).
1,4 -Dichlorobenzene. The subchronic and chronic inhalation RfD for 1,4
-dichlorobenzene is 0.7 mg/cu.m (HEAST). 1,4 dichlorobenzene is considered
as a probable human carcinogen (Group B2) and has an oral slope factor of
2.4E-2 (mg/kg/day)"1 (HEAST).
Dichlorodiphenyltrichloroethane (DDT). The subchronic and chronic RfD
for DDT is 5E-4 mg/kg/day (HEAST]. DDT is classified as a probable human
carcinogen (Group B2), and has an oral and inhalation slope factor of
0.34 (mg/kg/day)~L (HEAST).
Di-n-butyl phthalate. Subchronic and chronic RfDs for di-nbutyl phthalate
are 1.0 and 0.1 mg/kg/day, respectively (HEAST).
Polychlonnated Biphenyls (PCBs). PCBs are a complex mixture of polychlonnated
compounds which includes Aroclors 1242, 1254 and 1260. The chronic oral |
RfD for PCBs is based on a study using Aroclor 1016 (no data on noncarcinogid
effects of Aroclor 1260) and is 1E-4 mg/kg/day (ATSDR). PCBs are classified
as a probable human carcinogen with a slope factor of 7.7 (mg/kg/day) .
Polynculear Aromatic Hydrocarbons (PAHs). PAHs are a complex class of
compounds which includes: acenaphtftene, anthracene, benzo (a) anthracene,
benzo (a) pyrene, benzo (b) fluoranthene, benzo (g,h,i) perylene, benzo-
(k) fluoranthene, chrysene, dibenz (a,h) anthracene, fluorene, fluoranthene,
indeno (1,2,3 cd) pyrene, phenanthrene and pyrene. The subchronic and
chronic oral RfD for PAHs is based on the toxicity of naphthalene and is
0.4 mg/kg/day. PAHs are classified as probable human carcinogens (Group
B2), and have oral and inhalation slope factors of 11.5 and 6.1 (mg/kg
day) , respectively (EPA 1986). PAH slope factors are based on benzo-
(a)pyrene carcinogemcity. The following PAHs are considered to be
carcinogenic: benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene,
benzo(g,h,i)perylene, benzo(k)fluoranthene, chrysene, dibenzo(a,h)perylene,
benzo(k)fluoranthene, dibenzo(a.h) anthracene and indeno (1,2,3, cd)
pyrene.
Tetrachloroethylene (Perchloroethylene). The subchronic and chronic RfDs
for tetrachloroethylene are 0.1 and 0.01 mg/kg/day, respectively (HEAST).
Tetrachloroethylene is classified as a probable human carcinogen (B2),
and has an oral and inhalation slope factors of 5.1E-2 and 3.3E-3
(mg/kg/day)-l, respectively (HEAST). ^ ,
i
Toluene. The subchronic and chronic oral RfDs for toluene are 4E-1
and 3E-1 mg/kg/day, respectively (IRIS and HEAST). Subchronic
and chronic inhalation RfD for toluene is 2 mg/cu.m (HEAST). The
EPA determination of toluene carcinogenicity is pending (IRIS).
33
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1,2,4-Trichlorobenzene. The subchronic and chronic oral RfDs for 1,2,4-
tnchlorobenrzene are 2E-1 and 2E-2 mg/kg/day, respectively; subchromc
and chronic inhalation RfDs are 3E-2 and 3E-3 mg/kg/day, respectively
(HEAST).
1,1,1-Trichloroethane. The subchronic and chronic oral RfDs for 1,1,1-
trichloroethane are 9E-1 and 9E-2 mg/kg/day, respectively; and the subchronic
and chrome inhalation RfDs are 10 and 1 mg/cu.m (IRIS and HEAST). The
EPA determination of its carcinogenicity is pending (IRIS).
Xylene. For mixed xylenes, subchronic and chronic oral RfDs are 4E+0 and
2.0 mg/kg/day, respectively; and the chronic inhalation RfD is 3E-1 mg/cu.m.
(HEAST).
Inorganic Chemicals
Aluminium. The data on aluminium is inadequate for quantitative risk
assessment (HEAST).
Antimony. The subchronic and chronic oral RfD for antimony is 4E-4
(mg/kg/day) (IRIS and HEAST).
Arsenic. The subchronic and chronic oral RfD for arsenic is 1E-3 mg/kg/day
(HEAST). Arsenic is classified as a human carcinogen (Group A), and has
oral and inhalation slope factors of 1.8 and 1.5E+1 (mg/fcg/day)-l (IRIS).
Barium. For barium, the subchronic and chronic oral RfD is 5E-2 mg/kg/day
(IRIS and HEAST); subchronic and chronic inhalation RfDs are 5E-3 and 5E-4
mg/kg/day, respectively (HEAST).
Beryllium. The subchromc and chronic oral RfD for beryllium is 5E-3
(mg/kg/day) -1 (HEAST).
Cadmium. The chronic RfDs for cadmium are 1E-3 mg/kg/day (food) and 5E-4
mg/kg/day (water) (HEAST). Cadmium is considered as a probable hunian
carcinogen by inhalation (Group Bl) and has an inhalation slope factor of
6.1E+0 (mg/kg/dayT1 (IRIS and HEAST).
Chromium. The chronic RfD for chromium is 5E-3 mg/kg/day (IRIS). Chromium
is considered as a human carcinogen by inhalation (Group A) and has an
inhalation slope factor of 4.1E+1 (mg/kg/day)" (IRIS).
Cobalt. Quantitative risk assessment information on cobalt is not available.
Copper. For copper, the oral AIS and AIC is 3.7E-2 mg/kg/day and the
inhalation AIC is 1E-2 mg/kg/day (EPA 1986). Copper is not classified as
to human carcinogenicity (Group D) (IRIS).
Cyanide. The subchronic and chronic oral RfD for cyanide is 2E-2
mg/kg/day (HEAST).
34
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Lead. Lead car, have profound adverse effects or, certain blood enzymes
and on aspects of children's neurobehavioral development. These adverse
effects may o.ccur at blood lead levels so low as to be essentially without
a threshold (IRIS). For lead, oral AIC is 1.4E-3 mg/kg/day and inhalation
AIC is 4.3E-4 mg/kg/day (EPA 1986). Lead is classified as a probable
human carcinogen (Group B2) (IRIS and HEAST).
Manganese. For managanese, the subchronic and chronic oral RfDs are 5E-1
and 2E-1 mg/kg/day, respectively; and the subchronic and chronic inhalation
RfD is 3F-4 (HEAST). Manganese is not classified as to human carcinogenicity
(Group D) (IRIS).
Mercury. The subchronic and chronic oral RfO al kyl and inorganic mercury
is 3E-4 mg/kg/day (HEAST).
Nickel. The subchronic and chronic oral RfD for nickel is 2E-2 mg/kg/day
(HEAST). Nickel is Classified as a human carcinogen by inhalation (Group
A) and has an inhalation slope factor of 8.4E-1 (mg/kg/day) -1 (IRIS).
Selenium. For selenium, the subchronic and chronic oral RfDs an? 4E-3
and 3E-3 mg/kg/day, respectively; and the subchronic and chronic inhalation
RfD is IE-3 mg/kg/day (HEAST). j
Silver. The oral AIC for silver is 3E-3 mg/kg/day (EPA 1986). f
Vanadium. The subchronic and chronic RfD for vanadium is 7E-3 mg/kg/day
(HEAST).
Zinc. The subchronic and chronic RfD for zinc is 0.2 mg/kg/day (HEAST).
Risk Characterization
The first step in the risk characterization is to calculate the intake of
specific site-related contaminants Absorbed from the affected media.
Intakes by exposed populations will be calculated for the selected pathways
of exposure, and converted to daily doses (in mo/kg body weight/day) by
correcting for absorption efficiency across gastrointestinal , pulmonary,
or dermal boundaries. These doses are denoted by EPA as the chronic
daily intake (CDP. The CDIs for systemic (noncarcinoaenic) and carcinogenic
health effects are calculated separately to account for differences in ,
the averaging time.
The potential effects of contaminants on human health have been evaluated
for their noncarcinogenic and carcinogenic effects. For noncarcinogenic
effects, a chronic Hazard Index (HI) is calculated by summing the quotients
of the contaminant-specific CDIs by the contaminant specific RfDs or
AICs. A total (i.e, accounting for all media) HI greater than 1 suggests
a potential human health concern. For ground water exposure, the
evaluation of noncarcinogenic effects will focus on 1 to 6 year old
children, who are the most sensitive to contaminant exposures.
35
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For carcinogenic effects, the potential upper-bound lifetime excess cancer
risk (accounting for all contaminated media) is estimated by summing the
products of the contaminant-specific GDIs and the contaminant-specific
slope factors. EPA considers a lifetime upper bound of risk range of 10
to 10 as the target range for remedial action goals at Superfund sites.
EPA also considers the 1E-6 risk level as the "point of departure" for
remedial goals. This is the level that the agency expects to achieve
where practicable.
The dermal absorption route lacks the toxicity reference values of the
other exposure routes (e.g., oral and inhalation), Oral values were used
to assess risks from dermal exposure.
The results of the risk assessment indicate that no adverse health effects
would be expected from ingestion of the ground water near the site. PCBs
were not detected in any ground water samples taken. Data presented in
Table 2 indicates that the maximum concentration limits for metals were
not exceeded in any samples taken.
The risk assessment also indicated that non-carcinogenic risks from P'CBs,
metals, polynuclear aromatic hydrocarbons, and solvents are not present
at this site. The combined hazard index, the measure of non-carcinogeni- :
city, for direct contact with the contaminated soil was calculated to be i
0.55. A hazard index of 1.0 or greater is considered by EPA to represent »
a non-carcinogenic risk. '
Carcinogenic risks posed by the site are attributed to the PCB contamina-
tion in the soil. The average lifetime carcinogenic risk from direct
contact with the soil , based on the average concentration of PCBs in the
soil, is estimated to be 3.8 x 10 excess cancer incidents. Under the
"worst case" conditions, the estimated risk is 9.6 x 10, or approxi-
mately 1 x 10. PO!/nuclear aromatic hydrocarbons, metals, and sovlents
aid not contribute to the carcinogenic risks (less than 10 risk).
Environmental Assessment
The environmental risks associated with contaminants at the site appear
to be non-measurable or minimal. Surface water samples collected show no
organic chemicals related to the site and similar concentrations of inorganic
chemicals. Biota samples collected indicate that the North Canadian
River, downstream from the site contain more individuals and species than
upstream. The vegetation in the vicinity of the site ana cottonwood
trees along the intermittent stream west of the site did not appear to be
stressed. During 1987, the U.S. Fish and Wildlife Service of the Department
of the Interior conducted a Preliminary Natural Resource Survey and granted
a release from natural resource damages.
VII. DESCRIPTION OF ALTERNATIVES
As discussed earlier, PCBs are the contaminants of concern and are
limited to surface and subsurface soils at the site. Remedial
alternatives for the Tenth Street site have been evaluated with respect to
36
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nine aval nation criteria set in the National Contingency Plan, the Toxic
Substance Control Act (TSCA), PCS regulations; the Resource Conservation
and Recovery Act (RCRA), land disposal restrictions; the Oklahoma Solid
Waste Management Act, Regulations Governing Solid Waste and Sludge Management.
The PCB Spill Cleanup Policy, which is not an ARAR but is codified in the
Federal Register, has also been considered. The TSCA PCB regulations of
importance to Superfund sites are found in 40 CFR Part 761, Subpart D:
Storage and Disposal (761.60 - 761.79). These regulations specify the
treatment and disposal requirements for PCBs.
RCRA land disposal restrictions do not specifically apply to PCB
contamination, as PCBs alone are not a RCRA waste. However, if the
PCBs are mixed with other hazardous waste(s), they may be subject to land
disposal restrictions. The Oklahoma Regulations Governing Solid Waste
and Sludge Management specify landfill location standards, and the final
cover requirement. Under EPA Guidance or. Remedial Actions for Superfur.d
Sites with PCB Contamination (August 1990), land use (residential ,
industrial, or rural) is a primary consideration in determining cleanup
level. The concentration of PCBs that can be left in the soi'S on site
depends primarily on the expected exposure scenario (i.e. direct contact,
limited contact, or restricted contact through capping and access control')
and the achievement of adequate risk protection.
Remedial action is clearly warranted at Tenth Street based on the August '
1990 EPA guidance for PCB-contarainated Superfund sites. Section 3.U2 of }
this guidance discusses remedial goals for industrial or remote areas
with PCB contamination. A range of 10 ppm to 25 ppm is considered appropriate
for a remedial goal in an industrial area. This goal is consistent with
the goals set in the TSCA Spill Cleanup Policy.
The remedial goal for the Tenth Street site was set based on future
industrial land use and is 25 pprn PCBs in the soil onsite. This goal, was
selected to be consistent with the Toxic Substances Control Act Spill
Cleanup Policy criteria for commercial/industrial areas and goals set at
other Superfund sites nationwide where commercial exposures were considered.
This concentration also represents a maximum residual excess cancer risk
of 1 x 10" . This risk is based on a future commercial/industrial land
use. An estimated 7,500 cubic yards of soil to a depth of about 6 feet
are contaminated with greater than 25 ppm of PCBs and will be addressed
by the remedial action.
Alternatives Evaluation
To achieve the remedial goal, technologies and process options applicable
to this site were identified and analyzed. After the screening process,
a total of six alternatives were formulated. These alternatives were
further evaluated in terms of effectiveness, implementability, and cost.
Five alternatives were analyzed in detail in the FS. These five alternatives
are listed below and numbered to correspond with the alternatives in the
FS report.
o Alternative 1: No Action
o Alternative 3: Excavation and Offsite Disposal
37
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o Alternative 4: Excavation, Onsite Chemical Treatment
and Disposal Onsite
o Alternative 5: Excavation, Onsite Thermal Treatment, and
Disposal Onsite
o Alternative 6: Excavation and Offsite Thermal Treatment
Alternative 2, in place capping was screened out prior to the detailed eval-
uation of alternatives because the site is in a flood plain and because
capping would not satisfy the preference for treatment expressed in SARA.
Except for the "no action" alternative, all of the alternatives considered
for the site include a common component, the removal and/or treatment of
PCB contaminated soil. An air monitoring program and dust control measures
would be implemented to reduce/minimize any potential adverse snort-term
health effects during excavation and treatment activities. Institutional
controls would not be required for any of the alternatives, except the
"No Action" alternative.
Descriptions of each of the alternatives are as follows:
Alternative 1: No Action
Estimated Capital Cost: $2,500
Estimated Annual O&M Costs: $11,800
Estimated Total Present Worth Costs: $184,200
Estimated Implementation Timeframe: 30 years for O&M
The Superfund regulations (National Contingency Plan) requires that the
"no action" alternative be evaluated at every site to establish a baseline
for comparison. No construction activities would occur at the site; an
estimated 7,500 cu. yd. of PCB contaminated soil at concentrations of 25
ppm and above would remain at the site.
Under this alternative, deed restrictions to prohibit soi^ excavation
and construction activities would be imposed on the site, and regular
maintenance including vegetation mowing, reseeding, and fence and
cover surface repair would be performed. The two downgradient ground,
water monitoring wells would be sampled and analyzed for PCBs annually
to ensure that no migration of PCBs to ground water underneath the site
occurs. This alternative would meet neither the Toxic Substances Control
Act (TSCA) PCB disposal requirements, PCB Spill Cleanup Policy, nor the
Oklahoma Solid Waste Regulations. This alternative would not mitigate
the long-term risks identified with the contaminants at the site.
Because this alternative would result in contaminants remaining at
the site, CERCLA requires that the site be reviewed every five years.
38
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Alternative 3: EXCAVATION AND OFFSITE DISPOSAL
Estimated Capital Costs: $4,037,000
Estimated Annual O&M Costs: $0.00
Estimated Total Present Worth Costs: $4,037,000
Estimated Implementation Timeframe: 3 months
This alternative consists of the removal of the existing temporary red
clay cover and excavation and disposal of the PCs-contaminated soil in a
TSCA-permitted chemical landfill. The red clay removed could be retained
to supplement the clean soil required to backfill the excavated area.
The contaminated soil would be excavated and temporarily stored in waste
piles. The contaminated soil would then be loaded onto 20 cu. yd. dump
trucks for transport to a TSCA-permitted landfill. Prior to leaving the
site, the trucks would be inspected to ensure hazardous substance
transportation requirements are met. Manifests would also be prepared
and signed as required. The excavated area would be backfilled with r
clean soil. The final surface would be graded and seeded to blend with i
the surrounding area. I
Under this alternative, an estimated 7,500 cu. yd. of PCB contaminated
soil at concentrations of 25 ppm and above would be removed from the site.
During implementation of this alternative, measures to supress dust
generated during excavation will be used to mitigate any potential risk
to the nearby community may be expected due to fugitive dusts in the
ambient air. After completion of this alternative, no long-term monitoring
and maintenance would be required and the site risk would be reduced to
10" . This alternative would meet the TSCA PCB disposal requirements and
the PCB Spill Cleanup Policy.
Alternative 4: EXCAVATION, ONSITE CHEMICAL TREATMENT, AND DISPOSAL
ONSITE
Estimated Capital Costs: $4,044,000
Estimated Annual O&M Costs: $0.00
Estimated Total Present Worth Costs: $4,044,000
Estimated Implementation Timeframe: 6-9 months
This alternative consists of removing the existing red clay
cover and treating the PCB contaminated soil on-site by a chemical
process to destroy chlorinated biphenyls.
39
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After treatment, the treated soil (less than ? ppm PCB) would be put back
into the excavated area. The clay cover could be retained and used as
clean backfill material. If needed, additional clean soil would be brought
to the site for final grading.
The basics of the chemical dechlorination process are straight forward.
Contaminated soil is mixed with an alkaline reagent consisting of potassium
or sodium hydroxide in a solution of mixed polyethylene glycol and dimethyl
sulfoxiae. The reagent mixture dechlorinates the aryl halide to form a
PEG ether and a totally dechlorinated species.
In soil processing, the soil/reagent mixture is heated to 30 - 150 C with
mixing until the reaction has been completed. At the end of the reaction,
reagent is recovered by decantation and washing the soil with several
volumes of water. The decontaminated soil is then discharged, with the
reagent recycled for reuse. Water vapor and volatiles generated during
the process will pass through a condensor equipped with a carbon adsorption
filter before discharging to a waste treatment unit. Any volatiles that
are not condensed will be trapped by the filter. Spent carbon filters
will be handled in accordance with the waste classification. Chemical
analysis will be performed to ensure that discharged soil is clean.
A treatability study conducted during the RI indicated the KPEG treatment [
process to be a feasible and effective technology for decontaminating PCB '
contaminated soil at this site. This study demonstrated that this technology
can destroy PCB contamination at this site to below 1 ppm in the soil.
An estimated 7,500 cu. yd. of PCB contaminated soil with concentrations
of 25 ppm and above would be treated. The concentrations of the treated
residual would be reduced to less than 2 ppm. During implementation of
this alternatve, dust suppression and monitoring will be done to mitigate
any risk from fugitive dusts that may be generated. Emissions from the
treatment process would be minimal, water vapor and volatiles generated
which are not removed by the condensor unit would unit would be trapped
by carbon adsorption. Completion of this alternative would reduce the
site risk
required.
to 10 and no long-term monitoring and maintenance would be
This alternative would meet the TSCA PCB alternative treatment
requirements (2.0 ppm) and the PCB Spill Cleanup Policy.
Alternative 5: EXCAVATION, ONSITE THERMAL TREATMENT, AND DISPOSAL
ONSITE
Estimated Capital Cost: $4,406,000
Estimated Annual O&M Costs: $0.00
Estimated Total Present Worth Costs: $4,406,000
Estimated Implementation Timeframe: , 6"9 months
This alternative consists of removing the existing red clay cover and
treating the PCB contaminated soil on-site by an incinerator meeting the
40
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incineration destruction removal efficiency (ORE) of 99.9999 percent set
for PCBs by regulation. After treatment, the treated soil would put back
into the excavated area. The clay cover could De retained and used as
clean backfill material. Additional clean soil, if needed, would be
placed on top of the site for final grading.
Prior to incineration, contaminated soil would be excavated and stored
temporarily in waste piles. The contaminated soil would be fed into the
onsite incinerator equipped with emission controls and ash handling equipment,
The exhaust gases resulting from incineration would be scrubbed before
venting to the atmosphere.
The scrubber water would be incinerated or treated by passing through
serial activated carbon columns. The spent carbon would be incinerated.
The ash would be tested prior to backfilling the excavated area to ensure
PCBs are destroyed. A shredder would be used to reduce lumps of clay,
rocks, and other large debris to an acceptable size for incineration.
Large pieces of debris, such as bricks, rocks, or concrete found during
the excavation that can not be shredded would be assumed PC8 wastes and
disposed of in an approved landfill.
An estimated 7,500 cu. yd. of PCB contaminated soil at concentrations of j
25 ppm and above would be treated by the mobile incinerator brought onsite.
After incineration, the site risk would be reduced to 1E-6. No long-term f
monitoring and maintenance would be required. Any increase in risk by
inhalation due to the introduction of fugitive dusts in atmosphere by
soil excavation would be similar to Alternative 3. A potential increase
in risk by inhalation to the nearby community would also exist, if emission
control system of the incinerator were to fail. This alternative would
meet the TSCA PCB incineration requirements (40 CFR 761), the PCB Spill
Cleanup Policy, and the Oklahoma Clean Air Act.
Alternative 6: EXCAVATION AND OFFSITE THERMAL TREATMENT
Estimated Capital Costs: $17,829,000
Estimated Annual O&M Costs: $0.00
Estimated Total Present Worth Costs: $17,829,000
Estimated Implementation Timeframe: 3 months
This alternative consists of removing the existing red clay cover and
transporting the PCB contaminated soil to a permitted incineration facility
off-site. The PCB would be thermally destroyed at the off-site facility.
The cover soil removed could be retained to supplement the clean soil
required to backfill the excavated area and for final grading.
The contaminated soil would be excavated and temporarily stored in waste
piles ready for loading and transporation. The contaminated soil would
then be loaded onto 20 cu. yd. dump trucks. Prior to leaving the site,
41
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the trucks would be inspected to ensure hazardous substance transportation
requirements-are met. Manifests would also De prepared and signed as
required. The excavated area would be backfilled with clean soil. The
final surface would be graded and seeded to blend with the surrounding
area.
Implementation of this alternative would remove an estimated 7,500 cu.
yd. of PCB contaminated soil at concentrations of 25 ppm and above from
the site and reduce the site risk to 1E-6. No long-term monitoring and
maintenance would be required. During soil excavation, stockpiling, and
loading, this alternative would have a potential for temporary increases
in risk by inhalation to the nearby community similar to Alternative 3.
This alternative would meet the TSCA PCB incineration requirements and
the PCB Spill Cleanup Policy.
VIII. SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES
Overall Protection of Human Health and the Environment
All of the alternatives, with the exception of the "no action" alternative,r
would be comparable in terms of providing adequate protection of human |
health and the environment. They achieve protection by eliminating, i
reducing, or controlling risks through source removal and treatment. At ?
the cleanup level of 25 ppm, risks through direct^contact and ingestion
are reduced to aficancer risk maximum level of 10 . The overall average
site risk of 10 is achieved by treatment or removal of the contaminated
soil and the placement of treated soil on the site. Alternative 4, 5,
and 6 achieve protection by reducing exposure through treatment. Alternative
3 reduces risks by source removal. Under the "no action" alternative, as
long as the integrity of the existing soil cover is maintained, no imminent
and substantial endangerment to public health, welfare, or the environment
would be expected. However, contamination will remain at the site and
potential for contaminant migration will always exist. Also, site access
would be restricted and no excavations or construction activities would
be permuted at the site.
Compliance with ARARs
All of the alternatives, with the exception of the "No Action" alternative,
will achieve the 25 ppm remedial goal set in the TSCA Spill Cleanup Policy.
The use of a fully compliant land disposal facility permitted to accept
PCB-contaminated materials will ensure that Alternative 2, offsite land
disposal, meets the TSCA disposal regulations (40 CFR 761.75). Chemical
dechlorination will achieve the 2.0 ppm concentration set in the TSCA
Alternate Technology regulations. Both onsite and offsite thermal
destruction alternatives would comply with the incinerator regulations
governing PCB dispObl (40 CFR 761.70).
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Long-term Effectiveness and Permanence
Alternative 4,5, and 6 afford the highest degrees of long-term effectiveness
and permanence as they use treatment technologies to reduce hazardous
posed by contamination at this site. Alternative 4 uses a chemical treatment
technology while Alternatives 5 and 6 use thermal destruction. Both
chemical dechlonnation and incineration are irreversible processes.
Alternative 3 would provide the similar level of protection for this site
through source removal. However, the waste would not be destroyed, it
would simply be relocated to another Site. At 25 ppm, the average risks
from the site would be reduced to 10 by Alternatives 3, 4, 5, and 6.
Alternative 1 leaves all of the contaminated soil at the site and relies
entirely upon the existing soil cover. As the existing soil cover was
not constructed to meet the RCRA cap requirements, nor to meet the Oklahoma
Solid Waste Regulations final cover requirements, long-term effectiveness
and permanence of the existing soil cover is questionable.
Reduction of Toxicity, Mobility, or Volume
Alternatives 4, 5, and 6 would treat the contaminated soil to reduce the j
toxicity, mobility and volume of contamination at the site. At a cleanup .
level of 25 ppm, approximately 7,500 cu. yd. of PCB contaminated soil }
would be treated. About 1,000 cu.yds. of soil with PCB concentrations of
25 ppm and below would remain at the site. Alternative 4 would treat the
contaminated soil chemically and reduce the concentrations of contaminant
to less than 2 ppm. Alternatives 5 and 6 would involve incineration
processes that would have a ORE of 99.9999 percent.
Alternative 3, removal of the source of contaminantion and disposal
in a chemical waste landfill, would simply transfer the contamination
from one site to another and would not reduce the toxicity or volume
of the contamination. Alternative 1 will not reduce toxicity, mobility,
or volume of the contamination.
Short-term Effectiveness
Alternative 3, 4, 5, and 6 are anticipated to pose similar levels of
short-term risks. However, Alternative 4 would provide the greatest
short-term effectiveness and present the least amount of risk to workers,
the community, and the environment.
Particulate emissions resulting from excavation and stockpiling of contaminated
soil would be expected during implementation of Alternative 4. Emissions
generated from KPEG treatment process would be kept at minimum. Water
vapor and volatiles generated in the reactor will go through a condensor
equipped with a carbon adsorption filter before discharging into a waste
treatment unit. Any volatiles that are not condensed will be trapped by
the filter. Spent carbon will be handled in accordance with the waste
classification.
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The reagents and byproducts used in the chemical dechlorination process
will not pose any short term risks. Data generated in laboratory tests
using rats indicates tnat ethylene glycolate-400 is 27 times less toxic
than PCBs; dimethyl sulfoxide is 17 times less toxic than PCBs. These
reagents are also 9 and 6 times, respectively, less toxic than table salt.
The results of Ames toxicity tests indicates that the byproducts of the
dechlorination process do not exhibit any carcinogenic potential.
Alternatives 3 and 6 are very similar with respect to short-term effectiveness,
In addition to particulate emissions resulting from excavation of contaminated
soil, potential release of contaminants along the route of transportation
would exist, if an accident were to occur.
Alternatives 4 and 5 can be implemented in approximately 6 to 9 months.
Alternatives 3 and 6 can be completed in approximately 3 months.
Implementability
Alternatives 1, 3, and 6 would be the simplest to conduct and operate.
No special techniques, materials, permits, or labor would be required for
implementation of these alternatives; they are readily available in the
local area. Permitted PCB landfills and offsite PCB incinerators are
commercially available. j
Alternative 4, the KPEG treatment process, is more complex than Alternatives)
3 and 6. It would require specialists to construct and operate the system.
Pilot testing would be required to determine operating parameters and
fine tune the operation. During operation, this treatment process would
require constant attention and periodic adjustment.
Alternative 5 is probably the most complex alternative to operate. Despite
anticipated downtime due to mechanical complexity, incineration could
reliably meet the ORE. A mobile incinerator would have to be brought
onsite. This alternative would require the most attention as incineration
requires periodic sampling of the residue and modification of operating
parameters. A test burn would be required to determrnethe operating
parameters. Mobile incinerators are commercially available from numerous
vendors.
Cost
Alternative 1 has the lowest estimated present worth cost, $184,200. The
cost for Alternative 3 is estimated at $4,037,000. Alternative 4 has an
estimated cost similar to Alternative 3, $4,044,000. The estimated cost
for Alternative 5 is $4,0406,000, which is about IQ% higher than Alternative
4. Alternative 6 has the highest estimated cost, $17,829,000.00, which
is about 4.5 times higher than Alternative 4.
State Acceptance
The State of Oklahoma currently prefers the "No Action" alternative. The
State believes that because the baseline risk (10 ) is within.the remedial
target range established in the National Contingency Plan (10 to 10" )
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that further action is not warranted at the site. The State also believes
that the short-term risks of implementation of a remedy are greater than
the long-term .risks currently Dosed by the site, although the State did not
offer any quantitative evidence to substantiate the belief.
Community Acceptance
Community response to the alternatives is discussed in the responsiveness
summary, which addresses comments received during the public comment
period. Citizens raised questions about exposure to fugitive dust from
excavation, other locations where the technology has been used, and the
possibility of local contractors implementing the remedy.
IX. THE SELECTED REMEDY
Based upon consideration of the requirements of CERCLA, the detailed
analysis of the alternatives, and public comments, the U.S. EPA has selected
Alternative 4 - Excavation, Onsite Chemical Teatment, and Disposal Onsite
as the remedy for the Tenth Street Superfund site.
Soil sample analyses obtained during RI indicate that the estimated
volume of PCB contaminated soil at the site is approximately 8,500 cu.
yd. Based on the future industrial land use and compliance with the TSCA j
Spill Cleanup Policy, the remedial goal is set at 25 ppm. At this cleanup !
target, the increased cancer risk posed by the site would be reduced to I
ID'5.
An estimated 7,500 cu. yd. of soil contaminated with greater than 25 ppm
PCBs would be excavated and treated or.site by chemical dechlorination
treatment unit. The treated soil would contain less than 2 ppm of PCB.
A treatability study conducted during RI has demonstrated that the KPEG
treatment process is capable of destroying PCB contamination at this site
to below 1 ppm.
X. STATUTORY DETERMINATIONS
Under its legal authorities, EPA's primary responsibility at Superfund
Sites is to under take remedial actions that achieve adequate protection
of human health and the environment. In addition, Section 121 of CERCLA
established several other statutory requirements and preferences. These
specify that when complete, the selected remedy for this site must comply
with applicable or relevant and appropriate environmental standards established
under Federal and State environmental laws unless a statutory waiver is
justified.
The selected remedy also must be cost effective and utilize permanent
solutions and alternative treatment technologies or resource recovery
technologies to the maximum extent practicable.
Finally, the statute includes a preference for remedies that use technologies
that permanently and significantly reduce the volume, toxicity, or mobility
of hazardous wastes as their principal element. The following sections
discuss how the selected remedy meets these statutory requirements.
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Protection of Human Health and the Environment
The selected "remedy protects human health and the environment through
treatment of the PCB contaminated soil. The contaminant will be permanently
removed from the soil by glycolate dehalogenation process. The treatment
process will degrade the PCBs into less toxic, water soluble compounds
(glycol-ethers and chloride salts), which further degrade to form a totally
dechlonnated species.
Destruction of PCBs from the soil and backfilling the treated soil, in
the excavated area would reduce the excess cancer risk posed by the site
to 10" . Becuase the chemical dechlorination process equipment is
completely enclosed, there are no short-term threats associated with
materials handling with the selected remedy.
Compliance with Applicable or Relevant and Appropriate Requirements
The selected remedy of excavation, onsite chemical treatment,
and disposal of treated soil will comply with aU applicable or
relevant and appropriate requirements (ARARs). The ARARs are
presented below.
Action-specific ARARs:
|
o PCB Alternative Treatment Requirements (< 2 ppm PCBs)
PCBs, using total waste analysis (40 CFR Part 761,
Subpart D)
Other Criteria, Advisories or Guidance To Be Considered:
o TSCA PCB Spill Cleanup Policy (Federal Register, April 2, 1990)
o EPA Guidance on Selecting Remedies for Superfund Sites with PCB
Contamination (August 1990)
Land Disposal Restrictions under RCRA are not ARARs for the PCB-
contaminated soils at this site.
Cost - Effectiveness
The selected remedy is cost-effective, as it has been determined to provide
a high degree of effectiveness proportional to its cost. The estimated
total present worth value is $4,044,000. Tne selected remedy is the
least costly of the Alternatives 4, 5, and 6 which are equally protective
of human health and the environment.
Utilization of Permanent Solutions and Alternative Teatment Technologies
or Resource Recovery Technologies to the Maximum Extent Practicable
U.S. EPA has determined that the selected remedy represents the maximum
extent to which permanent solutions and treatment technologies can be
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utilized in a cost-effective manner for the final remedy at the Tenth
Street Superfund site. Of those alternatives that are protective of
human health and the environment and comply with ARARs, EPA has determined
that the selected remedy provides the best balance of tradeoffs in terms
of long-term effectiveness and permanence; reduction in toxicity, mobility,
or volume achieved through treatment, short-term effectiveness,
implementabil ity, costs, also considering the statutory preference
for treatment as a principal element and considering State and community
input. Alternative 1 would not reduce the toxicity, mobility or volume
of the contamination; would not comply with ARARs; would not provide
reliable long-term effectiveness; would provide short-term effectiveness;
would take 30 years to implement. Contamination will remain at the site
and potential for contaminant migration will always exist.
Alternative 3 would protect human health and the environment for this
site about equally as well as the selected remedy. It would also have
similar long-term effectiveness, and short-term effectiveness, However,
Alternative 3 would not reduce the toxicity or volume of the contaminant,
it would simply relocate the contamination to another site. Alternatives
5 and 6 would provide equal protection of human health and the environment
and long-term effectiveness as the selected remedy. They would also have
the same level of reduction in toxicity, mobility, and volume as the j
selected remedy. However, Alternatives 5 and 6 would have higher costs '
and less short-term effectiveness. I
Principal threats at Tenth Street are defined as those soils contaminated
with greater than 300 ppm PCBs, an order of magnitude higher than the
healthbased remedial goal. Low level threats are those soils with less
than 300 ppm PCBs. The NCP expects that principal threats will be treated;
low level threats will also be treated where cost-effective.
Containment of the low level threats was not considered because the cost
of treating all soils above the health-based remedial goal is only
approximately 10 percent of the cost of treating the high level threats.
Therefore, EPA considers treatment of all soil contaminated with greater
than 25 ppm PCBs to be cost-effective.
Preference for Treatment as a Principal Element
By treating the PCB contaminated soil at the site and disposing the treated
soil onsite, the selected remedy addresses the principal threat of future
direct contact/ingestion of contaminated soil posed by the site through
the use of treatment technologies. Therefore, the statutory preference
for remedies that employ treatment as a principal element is satisfied.
Documentation of No Significant Changes
The Proposed Plan for the Tenth Street site was released for public
comment in August 1990. The Proposed Plan identified Alternative 4,
chemical dechlorination of contaminated soil, as the preferred alternative.
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EPA reviewed all written and verbal comments submitted during the public
comment period. Upon review of these comments,it was determined that no
significant changes to the remedy, as it was originally identified in the
Proposed Plan, were necessary.
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Tenth Street Site
- Community Relations Responsiveness Summary
The Community Relations Responsiveness Summary has been prepared to
provide written responses to comments submitted regarding the Proposed
Plan at the Tenth Street hazardous waste site. The summary is divided
into two sections.
Section I: Background of Community Involvement and Concerns. This
section provides a brief history of community interest and concerns
raised during the remedial planning activities at the Tenth Street site.
Section II: Summary of Major Comments Received: The comments (both oral
and written) are summarized and EPA's responses are provided.
I: Background of Community Involvement and Concerns
The involvement in environmental issues, including hazardous waste
management is growing. Local chapters of national enviornmental
organizations and a variety of governmental groups are involved in
efforts to safeguard surface and groundwater resources. Community
concerns are that the contaminants from the site have leached into the
area's groundwater. In addition to concerns about grounwater quality,
members of the community fear that before the site was capped rainfall
could have washed hazardous waste from the surface of the landfill,
spreading contaminants beyond the boundary of the site to affect offsite
surface soil and water thus making the area unsafe for recreation.
II. Summary of Major Comments Received
Public notice announcing the public comment period and opportunity for a
public meeting was printed in the Daily Oklahoman on Sunday August 5,
1990. The proposed plan fact sheet was distributed to the site mailing
list on August 3, 1990. The comment period began on August 9, 1990 and
ended September 7, 1990. A public meeting was held on August 14, 1990,
at the James Stewart building in Oklahoma City, Oklahoma. The purpose of
this meeting was to explain the contamination problems at the site and
discuss the proposed and preferred alternatives.
Approximately 20 people were in attendance and 11 people asked questions
or made comments. One letter was received with comments.
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The comments/questions received during the public comment period concern
the following:
1. Comment: Could the chemicals used in the chemical dechlorination
process be conducted with the soil in place, instead of excavating
the soil?
EPA resporcse: No, in place dechlorination would not work at the Tenth
Street site. The clay soils on the site are too impermeable to allow
the chemicals to mix properly unless excavation is done. Without
proper mixing, the chemicals would not come in contact with the conta-
minated soils and proper decontamination could not occur. Research
conducted by EPA in 1987 also indicated that soils contaminated at
depths of greater than 2 feet were not adequately decontaminated by
applying the chemicals directly to the soil. Treatment of the deeper
contaminated soils at Tenth Street would not be effective unless
excavated.
2. Comment: What is the depth of contamination at the Tenth Street site?
EPA response: The soils at Tenth Street are contaminated with poly-
chlorinated biphenyls (PCBs) to a depth of 6 feet. These soils are
contaminated with PCBs at concentrations greater than 25 ppm, the
remedial action goal set for this site.
3. Comment: Does EPA currently have specifications for the chemical
dechlorination equipment to be used at Tenth Street?
EPA response: No, the specifications for this equipment have not been
written. Writing the specifications for remedial actions at Superfmnd
sites is done as part of the design. However, the development of the
technology in the feasibility study was done, in part, based on the
specifications of equipment currently available from vendors.
4. Comment: Will vendors who currently own the chemical dechlorinatiori
equipment be the only companies allowed to supply the equipment for the
remedy?
EPA response: No. Any vendor who has the equipment, or access to the
equipment that can implement the remedy will be allowed to bid on the
project. EPA, by regulation (Federal Aquisition Regulations), must
provide for fair and open competition among vendors when contracting
for Superfund work. Bidders must be able to demonstrate the capability
to perform the specified work during the bidding process with whatever
equipment they have available.
5. Comment: Where has chemical dechlorination been used on a full scale?
EPA response: Full-scale chemical dechlorination has been used to
successfully treat PCB and dioxin-contaminated materials at the Niagara-
Mohawk Power Company in New York, the Western Processing Company in
Washington, and the Montana Pole Treating Company in Montana.
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6. Comment: How much dust will be released into the air during remediation
and what precautions will be taken to protect the community from
windblown dust?
EPA response: During excavation, water sprays will be used to keep
the soil wet, minimizing the potential for dust to be generated.
The rate of soil excavation will also be correlated with the rate of
treatment to minimize the area of soil exposed to the wind at any given
time. Also, air monitors will be placed around the parimeter of the
site. These monitors will allow the EPA to determine if wind conditions
warrant a slower operation or temporarily ceasing operations due to
fugitive dust emissions.
7. Comment: Will there be an emergency evacuation plan for an event where
excessive dust is blown offsite?
EPA response: No. In the event that high winds generate excessive
dust, as measured by the ambient air monitoring, excavation will
be postponed until the wind conditions improve and fugitive emissions
can be controlled.
y
8. Comment: How many Technical Assistance Grants (TAGs) have been awarded"1 '.
in Region 6? j
EPA response: EPA Region 6 awarded a TAG to a community group in f
Albequerque, New Mexico for the South Valley Superfund site. This
grant was awarded on February 23, 1990. Three other grants were awarded
by EPA to a group in Jacksonville, Arkansas. However, competing local
groups have challenged the grants and final award is pending the reso-
lution of appeals.
9. Comment: One commentor requested a postponement of the public comment
period until a local community group has been awarded a TAG and received
the assistance necessary to evaluate EPA's Proposed Plan for the Tenth
Street site.
EPA response: In a letter dated September 7, 1990, this request was
denied by EPA. In arriving at this decision, EPA considered the
time required by the group to procure the services of an advisor were
the grant to be awarded in October 1990. EPA believes that, since the
grant may be used by the community group to review the design and
operation of the remedy, a delay in the selection of a remedial technology
is not warranted.
10. Comment: One commentor believed that a TAG would give local citizens
the opportunity to hire a consultant to conduct a remedial investigation
and feasibility study at Tenth Street.
EPA response: A TAG is not available for this purpose. This grant
are available for local citizen's groups to review and interpret EPA's
studies during all phases of a Superfund project. Grants are not
available for independent investigations conducted by local groups.
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11. Comment: A TAG would not be helpful to the local community after the
Recora of Decision is signed for the Tenth Street project.
EPA response: This is not true. TAGs may be used by the community
group to hire an advisor to review and interpret both the remedial
design and construction activities conducted at Tenth Street.
12. Comment: At what stage is application for the TAG and when might it
be awarded?
EPA response: A magnafax copy of the grant appliacation is being
.reviewed by the EPA Regional office in Dallas. The grant may be
awarded in October 1990, provided that an original, signed copy of
the application is received by the Regional office by September 30, 1990,
and the application complies with Federal grant regulations.
13. Comment: EPA appears to be delaying the award of a TAG until the
remedial action is completed.
EPA response: This is not true. Previous draft applications submitted
by the local citizen's group since March 1990 have been incomplete or
incorrect. EPA cannot, by grant regulations, award a TAG unless the
application is complete and correct. Representatives from EPA have
assisted the group on numerous occasions in correcting the application.
In some cases, comments on draft applications were not addressed in
subsequent submittdls.
14. Comment: Why was Alternative #2, Capping in Place, not considered at
Tenth Street?
EPA Response:. Construction of a cap on the Tenth Street site would not
satisfy the preference for treatment to reduce mobility, toxicity, or
volume stated in the Superfund law. EPA also expects, as outlined in
the National Contingency Plan (NCP), to treat wastes that constitute
a principal threat at a site. Soils contaminated with greater than
300 ppm PCBs are considered the principal threat at Tenth Street and
by regulation should be treated. Also, capping was not considered
an appropriate remedy because the site is in the 100-year flood
plain of the North Canadian River and would require perpetual maintenance
to prevent future exposure to contaminated soil.
15. Comment: How was the selection of the Proposed Plan among Alternatives
3, 4, and 5 made?
EPA response: These alternatives were compared against nine criteria
outlined in the NCP and the statutory preferences in the Superfund law.
Alternative 3, offsite land disposal, does not meet the statutory
preference for treatment as a principal element of the remedy. Offsite
disposal without treatment is also the least preferred alternative for
Superfund sites. Alternative 5, onsite thermal destruction, was not
proposed in favor of an innovative technology. The Superfund program
expects to select innovative technologies at sites where such a
technology is practiceable.
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16. Comment: Why is EPA selecting a technology rather than writing performance
specifications for cleaning up the site and taking bids on acceptible
solutions for addressing the contaminants at Tenth Street?
EPA response: The process by which EPA selects remedies at Superfund
sites is set forth in the National Contingency Plan (NCP). The NCP is
the regulation that governs the Superfund program. This process allows
EPA to screen out those technologies that are clearly inappropriate
for the Tenth Street site. As part of the design phase of this project,
performance specifications will be written. These specifications
will include the required level of treatment and length of time required
to complete the treatment process.
17. Comment: Has a health and safety plan for the construction at this
site been written?
EPA response: No. However, a health and safety plan, outlining
community and worker safety procedures, must be written and in place
prior to the start of construction activities at the site.
18. Comment: What is the current project schedule? ;
EPA response: EPA will select the remedy for Tenth Street in |
September 1990. The design of the selected remedy is scheduled to !
begin in March 1991, after a statutorily required moratorium period
to allow potentially responsible parties, if any, to take over the
project. The design will be completed in March 1992, with an
invitation for bids being released by EPA shortly thereafter. EPA
expects field work to be begin in Summer 1992 and end in Summer 1993.
19. Comment: EPA had already selected the remedy at the time of the
pub!ic meeting.
EPA response: This is not true. EPA had proposed a remedial
technology for the Tenth Street site at the public meeting. The
plan was proposed as the best technical solution for the site, based
on the criteria outlined in the NCP. EPA does not select the remedy
for a site until all of the comments made during the public comment
period have been considered.
20. Comment: What was the predominant species of PCBs found at Tenth
Street?
EPA response: The predominant species of PCBs found at Tenth Street
was Aroclor 1260.
?1. Comment: What are the toxicity and persistance of PCBs?
EPA response: EPA currently classifies PCBs as a Class B carcinogen,
or a probable carcinogen. The EPA Cancer Assessment Group has
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estimated the cancer potency factor to be 4.0 (mg/kg/day)~* and
has used this factor In health advisories issued by EPA. Based on
laboratory afiimal data, there is a potential for reproductive effects,
developmental toxicity in humans exposed to PCBs. PCBs are also
extremely persistant in the environment and can bioaccumulate in
the fatty tissues of exposed organisms (Federal Register,
July 10, 1986).
22. Comment: Does the cap that is currently on the site provide adequate
protection of human health and the environment form the contamination
at Tenth Street?
EPA response: No, it does not. The cap that was installed on the site
in 1985 by EPA was intended to temporarily prevent direct contact and
migration of contaminated soil. Stabilization of the site allowed
EPA to evaluate more permanent solutions to the problems at Tenth
Street. As seen by the current deterioration, the temporary cap
does not provide adequate long-term protection. As stated previously,
the degree of protection afforded by any cap is questionable because
the site is located in a 100-year flood plain.
23. Comment: To what extent have PCBs migrated offsite?
EPA response: Samples taken during the 1985 removal action indicates
that the only offsite PCB contamination exists in the right-of-way
between the north site boundary and Tenth Street at a depth of 3 to 4
feet below the surface. Surface soils are clean along the right-of-way
and do not pose a threat to pedestrians.
24. Comment: How deep were soil borings drilled during the remedial inves-
tigation?
EPA Response: Soil borings were drilled to a depth of six feet. Soil
samples taken at this depth were not contaminated above the remedial
goals, indicating that deeper borings were not necessary.
25. Comment: Can EPA promote the use of local firms for the remedial
work at Tenth Street?
EPA Response: EPA cannot give preference to local contractors because
of their location. However, local companies can have a competitive
advantage due to lower transportation costs. By the Federal,Acquisition
Regulations, the selection of a contractor to implement the selected
remedy must be done through an open and competitive bidding process.
EPA's prime contractor must also select subcontractors in,,,this..manner.
26. Comment: What will the consultant hired to design the remedy actually
do?
EPA response: The remedial design consultant will develop the contracts
and bid documents necessary to procure a contractor to implement the-
remedy selected in the Record of Decision. The consultant will not be
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directea to select a remedy for Tenth Street. The consultant will
also develop the specifications and blueprints for the remedy and
methods of verifying the performance of the contractor.
27. Comment: Shouldn't a consultant be hired to recommend a remedy for
Tenth Street?
EPA response: Consultants may be hired to develop and evaluate
potential remedial alternatives for consideration by EPA. The
responsibility to recommend and select remedies at Superfund sites
is solely EPA's by law.
?8. Comment: Is the equipment necessary for chemical dechlorination
commercially available?
EPA response: Yes, one manufacturer, Gal son Inc., of Syracuse, New
York, has built a full-scale unit for use with contaminated soils.
Other full-scale units have been used at the sites discussed in the
response to comment #6.
?9. Comment: How much time will be required to treat each batch of
contaminated soil in the chemical dechlorination unit?
EPA response: Experiences at other sites and the treatability
study conducted on the Tenth Street soil indicate that each batch
of soil can be treated to less than ?.0 ppm PCBs in approximately
4 hours. At this rate, the 7,500 cubic yards of soil at Tenth Street
can be treated in approximately 9 months.
30. Comment: What volumes of soil and reagent are mixed together in the
chemical dechlorination process?
EPA response: Approximately 2 tons of soil are treated by 1 ton of
reagent (potassium or sodium hydroxide, polyethylene glycolate 400,
and dimethyl suifoxide) in each batch treatment process. The reagents
are recovered for reuse in subsequent batches.
31. Comment: How large will the excavation area onsite be during imple-
mentation of the remedy?
EPA response: The excavated area will be approximately equal to
the rate of treatment. For example, EPA assumed in the feasibility
study that 30 cubic yards of soil would be treated per day. Excavation
would be done at the same rate with some material being stockpiled
prior to treatment.
32. Comment: Did the remedial investigation indicate the extent of the
original landfill at the site?
EPA response: No, it did not. EPA was primarily interested in PCB
contamination at the site. However, samples taken from borings and
monitoring wells indicated that no remnants from the original landfill
exist at the site.
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33. Comment: Will the material under the RGB-contaminated soil support
heavy equipment that may be needed to implement the selected remedy?
*>
EPA response: Yes. Soil logs taken from borings during the remedial
investigation indicate that the deeper soil is solid and will support
heavy equipment.
34. Comment: Will the selected remedy be sufficient to address any addi-
tional contamination that may be found after excavation begins?
EPA response: Yes, it will be able to handle any additional soil found
at the site. However, the length of time required to complete the
remedial action will increase.
35. Comment: Will there be any reason to close off parts of Tenth Street
to traffic during remediation?
EPA response: No, there won't be any reason to close of the street to
traffic. Windblown dust will be controlled by sprays and keeping the
area of excavation to a minimum. Chemical dechlorination will be done
in a completely enclosed unit, including reagent mixing, eliminating
air emissions from the process. Should weather conditions inhibit
excavation, operations would be postponed as a precaution.
36. Comment: Why was Tenth Street selected for cleanup as opposed to
otner sites in the area?
EPA response: Leaking drums discovered on the site in 1985 were removed
by EPA to prevent any exposure to local populations or the environment.
Because of the presence of PCBs in the soil and the potential for future
exposure, the site was placed on the National Priorities List, becoming
eligible for funding for investigations and permanent remedial action.
37. Comment: Does the Tenth Street site have the highest Hazard Ranking
System score of any NPL site in the Oklahoma City area?
EPA response: No. Two other NPL sites, Tinker Air Force Base and
the Mosley Road Landfill have higher scores. It should be noted that
relative scores are not used to set remedial priormes among Superfund
sites and represents only a conservative rating of potential threats
before any intensive studies are conducted.
38. Comment: Will further treatment of residuals be required after
chemical dechlorination is completed?
EPA response: Yes. Approximately 10 tons of solid residue from the
treatment process will require offsite disposal as a PCB waste.
Reagents are recovered and the treated soil will be used as backfill
onsite.
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39. Comment: Is the chemical dechlorination process d patented process?
EPA response: The general process is not patented. However, the use
of proprietary chemicals or specialized equipment has led to patents
on those variations by vendors. Contractors would have to negotiate
for patent rights or leases with vendors to use specific equipment.
40. Comment: PCBs at Tenth Street do not currently pose a threat to the
surrounding community; such a threat may potentially result only if the
site was disturbed.
EPA response: EPA never indicated that the site posed a current threat
to the community. The need to take remedial action is based on the
reasonable maximum exposure expected under future commercial land use.
The consideration of future land use in setting remedial action goals
is consistent with the National" Contingency Plan and the Risk Assessment
Guidance for Superfund, Volume 1, December 1989. EPA considers future
land use to be reasonable at Tenth Street based on the current surround-
ing land use (commercial) and inquiries that have been made to EPA
by parties interested in commercial development of the property.
41. Comment: Remedial action at Tenth Street is contrary to national
policy because the baseline (current) risk at the site is already j
within the remedial target range set by EPA. !
EPA response: The National Contingency Plan (NCP) and national
policy dictate that remedial action be taken at the site. The NCP
10"6 (i.e., 1 in 1,000,000) risk level as the "point of departure" for
determining remedial action goals when other standards are not available.
EPA expects to achieve this level of protection when practicable.
The NCP also dictates that remedial actions comply with Applicable
and Relevant and Appropriate Regulations and othsr policies and
guidelines. These are listed in the preamble to the NCP and include
the Toxic Substances Control Act PCB Spill Cleanup Policy (Federal
Register, April 2, 1987). As a matter of policy, EPA complies with
the cleanup levels set in the Spill Cleanup Pol fey. For commercial
areas, this level is set at 25 ppm PCBs in soil. Of the 32 Records
of Decision signed since the passage of SARA, for sites where PCBs
are the contaminant of concern, 5 have selected cleanup levels of 25
ppm PCBs. More stringent cleanup levels (10 ppm or less) have been
set at sites where residential exposures were considered.
42. Comment: Physical and legal restrictions could provide a level of
protection comparable to any remedial action taken at the site.
EPA response: Section 300.430 (a)(iii) of the NCP states that
institutional controls shall not substitute for active response actions
as the sole remedy unless such active measures are impracticable. A's
this is not the case at Tenth Street. SARA expects to use treatment,
not physical restrictions, as the principal element of remedial actions
at Superfund sites.
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43. Comment: The risk associated with the operation of the chemical
dechlon nation process should be compared to the long-term risks
posed by the-existing site.
EPA response: EPA does not measure short-term risks in the same manner
that long-term risks are measured. However, the toxicmes of the
reagents and byproducts of the process can be compared to the toxicity
of PCBs as a measure of the relative risks. A comparison of the reagents,
the byproducts, PCBs, and other reference materials is presented below:
MATERIAL LD5Q> ORAL-RATS
Polyethylene glycol-400 27,500 mg/kg
Dimethyl sulfoxide 17,500 mg/kg
PCBs 1,010 mg/kg
This data indicates that PCBs, the contaminants of concern at Tenth
Street, are 27 times more toxic than polyethylene glycolate and 17
times more toxic than dimethyl sulfoxide, the reagents in the chemical
dechlorination process. Ethylene glycol-400 is also approved by the
Food and Drug Administration for use in food and cosmetics. Trie
LD5g is the dose that causes mortality in 50 percent of the test
organisms. These tests were conducted on laboratory rats, considering
oral ingestion. EPA research also indicates that dechlorinated mixtures
of 2,3,7,8-tetradioxin are 350 times less toxic than 2,3,7,8-tetradioxin
itself. The treatment byproducts do not demonstrate any carcinogenic
potential based on the results of Ames tests conducted by EPA.
Materials handling will not pose any short term risk during implementation
of the remedy. Existing chemical dechlorination equipment is completely
automated. Reagents, byproducts, and soils are handled in completely
enclosed systems using pumps and conveyor belts for materials handling.
The system also addresses air emissions through condensers for water
vapor and carbon filters for volatile orgartics. No contaminants
are released to the atmosphere during the treatment process.
10
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INTRODUCTION
Section 113(j)(l) of the comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) provides that judicial
review of any issues concerning the adequacy of any response action
shall be limited to the administrative record vhich has been
compiled for the site at issue.
Section 113(JO (1) of CERCLA, requires that the United States
Environmental Protection Agency (Agency) establish administrative
records for the selection of CERCLA response actions. The
administrative record is the body of documents upon which the
Agency based its selection of a response action. The Agency's
decision on selection of a response action must be documented
thoroughly in the administrative record. The Agency must ensure
that the record is a compilation of documents leading up to and
reflecting the Agency's response decision.
In accordance with U.S. EPA Headquarters OSWER Directive 9833.3,
Section 113(k) of the Comprehensive Environmental Response,
Compensation and Liability Act (CERCLA), as amended in 1986
by the Superfund Amendments and Reauthorization Act (SARA)
the U.S. EPA is required to compile and make available to the
public Administrative records containing documents used to
support response actions authorized under CERCLA and SARA.
The Administrative Records are to be maintained at the relevant
U.S. EPA Regional Offices as well as "at or near the facility at
issue".
This Administrative Record File Index has been compiled in
accordance with OSWER Directive Number 9833.la Interim Guidance
on Administrative Records for Decisions on Selection of CERCLA
Response Actions. This guidance reflects, to the extent practicable,
revisions being made to the National Contingency Plan (NCP).
This Administrative Record File Index consists of information
upon which the Agency based its decision on selection of response
actions. It is a subset of information included in the site
files. The records in this Administrative Record File Index
have been arranged in chronological order (from the earliest
date to the most recent date), based on the date of the corres-
ponding document. Each document contained in the Administrative
Record File has been stamped with a unique Document Number, to
assist in the location of the document within the Record File.
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09/28/89 Administrative Record - Category Number Order Page:
Tenth Street
Document Number: u-0001
Date: 02/07/83
Document Title : Potential Hazadrous Kaste Site - Site inspection Report: frazier Pit [10th Street Site], N.E. JOth Street, Okie
City, Oklahoma
Type: Report/Study
Document Qualifiers(s):
Author: Phi Ip E. Suaner, Jr., FIT Civil Engineer
Ecology t Environment, inc.
Original/Duplicate of Original,
Recipient: Staff
Region 6
Total Pages: 15
Document Number: 11-0002 Date: 09/21/84
Document Title : A memorandum providing information as requested by USEPA regarding 10th Street Site.
Type: Memorandum
Document Qualifiers(s):
Author: Kib Truby
Oklahoma State Department of Health
Recipient: fenton Rood
Oklahoma State Department of Health
aI Pages: 2
Original/Duplicate of Original,
document Number: 11-0003 Date: 10/01/84
Document Title : A Section I04(e) letter requesting information related to activities at the Iflth Street Site.
Type: Letter
Document Qualifiers(s):
Author: Allyn If. Davis, Director
USEPA Region 6, Air I Haste Management Division
Recipient: William Spain, President
Southwest Electric Co.
Total Pages: 3
Original/Duplicate of Original,
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09/28/89 Administrative Record - Category Number Order Page:
Tenth Street
;ent Number: 11-0004 . Date: 10/01/84
Document Title : Sampling report for the N.E, Iflth Street Site.
Type: Report/Study
Jocuaent Qualifiers(s): Original/Duplicate of Original,
Author: Frank E. Onellion, TAT
Yeston-Sper
Recipient: Charles A. Gazda, Chief
USEPA Region 6, Emergency Response Branch
"otal Pages: 23
Jocuaent Number: 11-0005 Date: 10/02/84
Document Title : Site inspection to deiinate the area that contained druis of suspected hazardous waste.
I Report/Study
ent Qualifiers(s):
Author: Frank E. Onellion, TAT
Yeston-Sper
Recipient: Charles A. Gazda, Chief
USEPA Region 6, Eaergency Response Branch
Total Pages: 24
Original/Duplicate of Original,
Jocuaent Number: 11-0006 Date: 10/17/84
)ocument Title : A response to the Section I04(e) request letter, froi Southwest Electric Co.
.rype: Letter
)ocunent Qualifiers(s):
Author: Yillian I. Spain, President
Southwest Electric Co.
Recipient: Allyn H. Davis, Director
USEPA Region 6, Air S Haste Hanageaent Division
"otal Pages: 3
Original/Duplicate of Original,
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Adainistrati ye Record - Category Nuaber Order Page:
Tenth Street
Document Nuaber: 11-0007 Date: 12/12/84
Oocuaent Title : A written record of Testimony before the Subcoaaittee on Environaent, Energy and Natural Resources concernin
geohydrology of the area of Tinker Af8.
Type: Report/Study
Document Qualifiers(s): Original/Duplicate of Original,
Author: Or. Charles J. Nankin, Director
Oklahoma Geological Survey
Recipient: Subcomittee on Environment,Energy I NtR
United States Congress
Total Pages: 12
Document Nunber: 11-0008 Date: 04/17/85
Docuraent Title : COC review of IQth Street Site data.
Type: /leaorandua
Oocuaent Qualifiers(sJ: Original/Duplicate of Original,
Author: Georgi A. Jones, Chief, Superfund fapleaentation Group
USHHS, Public Health Service, COC
Recipient: George C. 8uynoski,Public Health Advisor
USEPA Region 6
Total Pages: I
Oocuraent Number: 11-0009 Date: 05/15/85
Oocunent Title : Soil Saapling: Saapling of the 10th Street Site by the Technical Assistance Tea*.
Type: Report/Study
Oocunent Qualifiers(s): Original/Duplicate of Original,
Author: Dennis N. Howard, TAT Henber
Keston-Sper
Recipient: Gerald fontenot, Deputy Project Officer
USEPA Region 6, Energency Response Branch
Total Pages: 12
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09/28/89 Adainistrative Record - Category Number Order Page:
Tenth Street
lent Nuaber: 11-0010 Date: 05/23/85
Oocuaent Title : A letter describing the findings and possible health effects at the 10th Street Site, and requesting assistance in
the Uniting of access to the site.
Type: Letter with Attachaents
Docunent Qualifiers!*): Original/Duplicate of Original,
Author: Fred P. Walker,PhD., Environmental Epideaiologist
Oklahoaa State Department of Health
Recipient: Roll in Fullbright
Oeadeye's Salvage yard
Total Pages: 4
Document Nuniber: 11-0011 Date: 06/05/85 i
Oocuaent Title : A Section 104(e) letter requesting information related to activities at the 10th Street Site. j
Type: Letter
Qualifiers(s): Original/Duplicate of Original,
Author: Allyn H, Davis, Director
USEPA Region 6, Air i Waste Management Division
Recipient: Oklahoma Gas i Electric
Oklahoaa City, Oklahooa
Total Pages: 3
Jocunent Number: 11-0012 Date: 06/21/85
Jocuaent Title : A Section IQ4(e) letter requesting information related to activities at the 10th Street Site.
ype: Letter
ocument Qualifiers(s): Original/Duplicate of Original,
uthor: Allyn II. Davis, Director
USEPA Region 6, Air t Waste Hanagement Division
'cipient: Cecil Joe
Jesus is Lord Salvage Yard
3
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09/28/89 Administrative Record - Category Number Order Page:
Tenth Street
Document Nuiber: 11-0013 - Date: 06/28/65
Document Title : Response from Oklahoma Gas 1 Electric to Section I04(e).request letter.
Type: Letter
Document Qualifiers(s): Original/Duplicate of Original,
Author: C.L. Tyree, Chief, Environmental Affairs
Oklahoma Gas t Electric
Recipient: Hartha H. HcKee
USEPA Region 6
Total Pages: 2
Document Number: 11-0014 Date: 07/10/85 i
Document Title : A Section 104(e) letter requesting information related to activity at the 10th Street Site.[Second Request)
,,r
Document Qualifiers(s): Original/Duplicate of Original,
Author: Robert Hannesschlager, Acting Chief
USEPA Region 6, Superfund Branch
Recipient: Sullivan Scott
Oklahoma City, Oklahoma
Total Pages: 2
document Number: 11-0015 Date: 07/11/85
Document Title : A Section 104(e) letter requesting information relating to activities at the 10th Street Site.
Type: Letter
Document Qualifiers(s): Original/Duplicate of Original,
Author: William B. Hathaway, Acting Director
USEPA Region 6, Air I Waste Management Division
Recipient: General Electric Company
Oklahoma City, Oklahoma
fotal Pages: 3
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09/28/89 Administrative Record - Category Nurter Order Page:
Tenth Street
lent Nunber: 11-0016 - Date: 07/11/85
Oocuaent Title ; A Section I04(e) letter requesting information related to activity at the 10th Street Site.
Type: Letter
Docunent Qualifiers(s): Original/Duplicate of Original,
Author: Williai 6. Hathaway, Acting Director
USEPA Region 6, Air i Haste Management Division
Recipient: flier Cobb
Oklahoma City, Oklahoma
Total Pages: 3
Document Nunber: 11-0017 Date: 07/15/85
Document Title : A response from Joe Cecil to the Section IflX(e) letter of June 21,1985.
DonMt Qualifiers(s): Original /Duplicate of Original,
Author: Joe Cecil
Jesus is Lord Salvage Yard
Recipient: Staff
USEPA Region 6
Total Pages: 1
Document Nunber: 11-0018 Date: 08/07/85
Oocunent Title : Response by the General Electric Company to the Section I04(e) request letter.
Type: Letter
Oocunent Qualifiers(s): Original/Duplicate of Original,
Author: Eugene R. Baker, Counsel
General Electric Conpany, Engineered Materials Group
Recipient: Martha McKee
USEPA Region 6
Total Pages: I
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09/28/89 Administrative Record - Category Number Order Page: 7
Tenth Street
Document Number: 11-0019 . Date: 08/23/85
Document Title : ACTION MEMORANDUM - I Mediate Removal Request for the 10th Street Site, Oklahoma City, Oklahoma.
Type: Memorandum
Document Qualifiers(s): Original/Duplicate of Original,
Author: Karen Solari, OSC
USEPA Region 6, Field Response Section
Recipient: Dick Yhittington,P.E.,Reg. Administrator
USEPA Region 6
Total Pages: 5
Document Nuaber: 11-0020 Date: 08/29/85 j
Document Title : ADMINISTRATIVE ORDER directing tnat certain remedial activities be undertaken at the Iflth Street Site. (
Type: Miscellaneous
Document Qualifiers(s): Original/Duplicate of Original,
Author: Frances E. Phillips for Regional Administrator
USEPA Region 6
Recipient: Sullivan Scott/Elmer Cobfa
Oklahoma City, Oklahoma
Total Pages: 12
Docuaent Nunber: 11-0021 Date: 09/24/85
Document Title : Final Report: Off-site sampling at the 10th Street Site [08/85] [Includes Sampling Data]
Type: Heiorandua
Document Qualifiers(s): Original/Duplicate of Original,
Author: Thonas A. Halzer, FIT Chemical Engineer
Ecology I Environment, Inc.
Recipient: Keith Bradley, RPO Region VI
USEPA Region 6
Total Pages: 23
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09/28/89 Administrative Record - Category Number Order Page: 8
Tenth Street
«nt Number: 11-0022 . Date: 10/29/85
Document Title : HRS Package: Includes sampling data for preliminary assessment with summaries.[Located in site file, USEPA Region 6,
Dallas]
Type: Miscellaneous
Oocuaent Qualifiers(s): Original/Duplicate of Original,
Author: Reference as to location
Recipient:
Total Pages: 478
Document Nunber: 11-0023 Date: 10/30/85
Document Title : Sampling Data Results, Chain of Custody Records for Sept. 1985 [Available in ER. Vol.4, USfPA Region 6, Oajlas]
Sampling/Analyses/Data
nt Qualifiers(s): Original/Duplicate of Original,
Author: Reference as to location
Recipient:
Total Pages: 0
Document Hunter: 11-0024 Date: Of/15/86
document Title : A memo describing different areas and locations of hazardous wastes at the 10th Street Site, vith a up.
Type: Memorandum
Jocument Qualifiers(s): Original/Duplicate of Original,
Author: Staff
Sunbelt Environmental Management, Inc.
Recipient: Site File
t USEPA Region 6
jes: 2
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09/28/89 Administrative Record - Category Number Order Page:
Tenth Street
Document Number: 11-0025 Date: 05/05/86
Document Title : ACTION HEHORANOUH - Six Honth Time Exemption to Allow Continuation of Removal Activities at the 10th Street Site.
Type: Hemorandum
Document Qualifiers(s): Original/Duplicate of Original,
Author: Karen Solari, OSC
USEPA Region 6, Field Response Section
Recipient: Dick Whittington,P.E.,Reg. Administrator
USEPA Region 6
Total Pages: 2
Document Number: 11-0026 Date: 01/23/87
Document Title : 'Salvage Yard Hakes EPA List" A news article on the addition of the l§th Street Site to the NPL.
Type: Newspaper/Journal Article
Document Qualifiers(s): Original/Duplicate of Original,
Author: Wayne Singleterry
The Daily Oklahoman
Recipient: Site File
USEPA Region 6
Total Pages: I
Document Number: 11-0027 Date: 09/24/87
Document Title : After Action Report for the Iflth Street Removal Action.
Type: Memorandum
document Qualifiers(s): Original/Duplicate of Original,
\uthor: Charles A. Gazda, Chief
USEPA Region 6, Emergency Response Branch
Recipient: Robert E. Hannesschlager, Chief
USEPA Region 6, Superfund Branch
otaI Pages: 33
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09/28/89 Administrative Record - Categor, Number Order Page: 10
Tenth Street
lent Nuiber: 11-0028
Date: 04/01/89
Document Title : Horkplan; Site Sampling J Quality Assurance/Quality Control Plan; Site Safety plan for the Iflth Street Superfund
Site, Olahoia City, Oklahoma
Type: Miscellaneous
Document Qualifiers(s):
Author: Staff
USEPA Region 6, Hazardous Waste Hgmt Division
Recipient: Site file
USEPA Region 6
Total Pages: 119
Original/Duplicate of Original,
Oocunent Number: 11-0029 Date: 09/15/89
Document Title : Community Relations Plan
TuflACommunity Relations Plan
OoaPnt Qualifiersfs):
Author: Staff
USEPA Region 6, Hazardous Haste Division
Recipient: Site File
USEPA Region 6
Total Pages: 26
Original/Duplicate of Original,
Oocunent Number: 11-0030 Date: 09/28/89
Document Title : RI Sampling Data [Results currently in review and interpellation] (Contact RPH, USEPA Region 6)
Type: Sampling/Analyses/Data
Document Qualifiersfs):
Author: References as to location
Original/Duplicate of Original,
Recipient:
otaI Pages: 0
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ADMINISTRATIVE RECORD INDEX
ADDENDUM
SITE NAME: TENTH STREET DUMP SITE
SITE NUMBER: OKD 980620967
INDEX DATE: 08/02/90
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SITE NAME:
SITE NUMBER:
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
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DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
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AUTHOR:
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RECIPIENT:
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ADMINISTRATIVE RECORD INDEX
ADDENDUM
TENTH STREET DUMP SITE
OKD 980620967
31
05/31/89
026
Office fo Waste Programs Enforcement
U.S. EPA HQ
U.S. EPA Region 6 Site Files
Compendium and Users Manual
"Compendium of CERCLA Response Selection Guidance Documents
Users Manual"
32
03/31/90
090
EPA Staff
U.S. EPA Region 6
U.S. EPA Region 6 Site Files
Report
Remedial Investigation Report - Volume 1
33
03/31/90
386
EPA Staff
U.S. EPA Region 6
U.S. EPA Region 6 Site Files
Report
Remedial Investigation Report - Volume 2
34
05/31/90
004
EPA Staff
U.S. EPA Region 6
U.S. EPA Region 6 Site Files
Site Update
"Tenth Street Site Update"
A-l
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SITE NAME:
SITE NUMBER:
DOCUMENT NUMBER:
DOCUMENT DATE:
NUMBER OF PAGES:
AUTHOR:
COMPANY/AGENCY:
RECIPIENT:
DOCUMENT TYPE:
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ADMINISTRATIVE RECORD INDEX
ADDENDUM
TENTH STREET DUMP SITE
OKD 980620967
35
06/30/90
068
EPA Staff
U.S. EPA Region 6
U.S. EPA Region 6 Site Files
Assessment
"Baseline Risk Assessment for the Tenth Street Dump Superfund
Site, Oklahoma City, OK"
36
07/02/90
017
EPA Staff
U.S. EPA Region 6
U.S. EPA Region 6 Site Files
Plan |
"Proposed Plan - Tenth Street Superfund Site, Oklahoma City,
OK"
37
07/31/90
138
EPA Staff
U.S. EPA Region 6
U.S. EPA Region 6 Site Files
Report
Feasibility Study Report for Tenth Street Superfund Site -
Oklahoma City, OK
I
A-2
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Joan K. Leavitt, M.D.
Commissioner
OKLAHOMA STATE
DEPARTMENT OF HEALTH
Board of Health
Walter Scott Mason, III
President
Ernest D. Martin, R.Ph.
Vice President
Wallace Byrd, M.D.
Secretary-Treasurer
John B. Carmichael, D.D.S.
Jodie L. Edge. M.D. ?'
Dan H. Fieker. D.O.
Burdge F. Green, M.D.
Linda M. Johnson, M.D.'
LeeW. Paden ' '
P.O. BOX 53551
> 1000 NE TENTH
OKLAHOMA CITY, OK 73152
AN EOUM. OPPORTUNITY EMPlOrtR
Septembers, 1990
Robert E. Layton Jr. (6A)
Regional Administrator
EPA Region VI
1445 RossAve.
Dallas, Texas 75202
Dear Mr. Layton:
I have reviewed the data gathered through the Remedial Investigation of the Tenth
Street Superfund Site and the actions proposed in the Feasibility Study (FS). I
am concerned that the information contained therein does not justify the proposed reme-
dial action as presented in the Proposed Plan.
The fact that PCBs are the only compounds detected at significant levels at the site is
clearly stated in the Feasibility Study. Moreover, it is a given that due to the binding char-
acteristics of the PCB molecules to soil particles, the likelihood of any migration of the
contamination is extremely unlikely. This means that the PCBs do not currently pose a
hazard to the surrounding community and that only through some mechanism of distur-
bance would the potential for exposure be realized.
The FS also states that to arrive at soil concentrations for target remediation goals for
PCBs, an assumption is made that the most probable land use of this site would be
industrial and therefore, the primary goal of remediation would be the protection of work-
ers at an industrial facility. The lifetime risk posed by the site, assuming an-industrial
exposure scenario, is estimated in the FS as being 38 cancer incidents per 1,000,000
people (3.8E-5) if the average contaminant concentrations of 110 ppm are used. If the
"worst case" scenario is postulated, 96 incidents per million people (9.6E-5) might be
expected.
EPA guidance has established 1.0E-4 to 1.0E-6 as the acceptable range of risk for
Superfund Remedial Actions. Both the "average" and "worst case" contaminant concen-
trations fall within this range, making clean up of this site for the most probable land use
unnecessary and counter to national policy. The same public health protection could be
achieved through the use of physical and legal land use restrictions. If the property was
converted to industrial use the owner could be required to conduct any remedial actions
necessary to protect the health of future workers.
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Robert E. Layton Jr.
Page 2
Septembers, 1990
The Proposed Plan for the Tenth Street Site recommends treating part of the PCB con-
taminated soils using the Potassium Polyethylene Glycol (KPEG) process. The KPEG, is
a highly complex and intricate process that has a very limited testing and performance
record at the scale of the proposed Tenth Street project. The limited scale tests that have
been accomplished to date show that the process is based on sound chemical theory.
But, my concern is that operation of a full size facility will prove realistically unfeasible and
potentially dangerous due to the large volumes of hazardous chemicals required for the
process. The risk associated with the operation of a KPEG facility should be quantified
for comparison to the risks posed by the existing site. Without any comparison of relative
risks or realistic operating experience for the KPEG process, I am concerned that the
proposed remedial action is essentially an experiment with the piijlic health of the people
of Oklahoma.
If you have any questions or comments regarding this matter please call me at (405)
271-8056.
Sincerely yours,
S. Coleman, Deputy Commissioner
for Environmental Health Services
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