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FINAL DECISION AND
RESPONSE TO COMMENTS
RCRA CORRECTIVE ACTION PROGRAM
ANCHOR RANCH
POTTSBORO, TEXAS
THE PURPOSE OF THIS
FINAL DECISION AND
RESPONSE TO COMMENTS IS
TO:
• Describe the selected
remedy;
• Explain EPA 's rational for
the remedy selected; and
• Identify and respond to any
comments received during
the public comment period.
August 13, 2001, to September 15, 2001.
INTRODUCTION
This Final Decision and Response to Comments is
being presented by the U.S. Environmental Protection
Agency (EPA) for the drum burial site on Anchor
Ranch, which is located near Pottsboro, Texas. The
purpose of the Final Decision is to describe the
selected remedy at this site, present concerns and
issues raised during the public comment period, and
to provide responses and rationale for any comments
received. This document consists of the Final
Decision, an updated index to the Administrative
Record (Attachment I), and the previously issued
Statement of Basis (Attachment II).
EPA selects the remedy based on the Administrative
Record and any public comments received. The
Statement of Basis provided the proposed remedy and
was available for public review and comment from
SITE DESCRIPTION AND STATUTORY DETERMINATION
The drum burial site is located on a ranch approximately two miles north of the City of Pottsboro
in Grayson County, Texas, as shown in Figure 1. The site is near the south fence of a pasture
used for cattle grazing. The property, owned by C. D. Loe, Jr., is known as "Anchor Ranch" and
consists of 137 acres on the south side of Cemetery Road approximately three-tenths of a mile
west of State Highway 120.
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FIGURE 1
Drum Burial
Site n
Pottsboro
- 1-
EPA conducted an inspection of the site in October 1996 and found 25 drums buried on the
property at a depth of about 4 feet. The crushed and leaking drums were found to contain
various hazardous constituents including methylene chloride, di-methyl phenol, phenol, and
benzene. Soils in the drum burial site were contaminated by the wastes spilled from the drums.
The contaminants identified at the site include known and suspected carcinogens, which can
affect the central nervous system and damage internal organs at low levels. The drums were
removed from the burial site in October 1996 and sent off-site for disposal at a licensed facility
in February 1997.
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On June 4, 1997, EPA and C.D. Loe, Jr. signed an Administrative Order on Consent under
RCRA, Section 7003. The Order required an investigation and cleanup of any remaining
environmental contamination resulting from burial of the drums at Anchor Ranch.
SELECTED REMEDY
The soil at the site that was contaminated above acceptable risk-based concentrations was
removed as an action in EPA's corrective action program. Subsequent to that removal,
investigations performed at the site demonstrate that the threat to human health or the
environment from hazardous constituents is acceptable. EPA's determination is that the
previous removal is sufficient to protect human health and the environment, and that no further
corrective action is necessary for the drum burial site at the Anchor Ranch.
REMEDY COMPLETED
The contaminated soil in the drum disposal area was excavated in October 1997 while the site
investigation was underway and before the final measures were determined. The soil was
removed to control or minimize the ongoing threats to human health and the environment in
advance of the final remedy selection. The removal was accomplished by removing the upper
2 feet of soil in the drum burial area out to 1 foot beyond the original perimeter. Following this,
four soil samples were collected from the sides of the pit.
Excavation then resumed to a depth of 4 feet and a scan was conducted with a photo-ionization
detector (OVM 580 PID) to investigate the presence of organic vapors. Additional excavation
was done to a depth of 5l/2 feet in areas with elevated organic vapor readings. Five additional
soil samples were collected from the sides and bottom of the pit. All confirmatory samples were
collected from areas with the highest organic vapor concentrations measured by the photo-
ionization detector. The excavation area is shown in Figure 2.
The soil samples were analyzed for volatile and for semi-volatile organic compounds using EPA
laboratory methods. Analytical results of the soil samples taken from the sides of the pit within
2 feet of the surface showed that all detectable contamination above a depth of 2 feet had been
removed. The soil samples collected between 4 feet and 5 l/2 feet established that organic
chemical concentrations were either below detection limits or less than the EPA Region 6
Human Health Media-Specific Screening Levels for Residential Exposures.
The drum burial site was backfilled with soil obtained off-site from Honeycutt Sand and Gravel
located at 2201 Bowers Road, Seagoville, Texas. Following grading, the excavation pit, soil
staging area, and surrounding areas were re-seeded with grass.
Additional sampling, described in the attached Statement of Basis, showed that nearby soils,
sediments, and ground water were not contaminated by the drum burial site.
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FIGURE 2
Drum Burial Site ^
CS-2 -r
Hatched Area Excavated to
Depth of 5.5 Feet
CS-3
CS-7
Approx. Depth = 4.0 Feet
Excavation!
Area
LEGEND
Represents Confin
nple Location
from "Interim/Stabilization Measures Report"; May 29, 1998; W.E.S.T.
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SUMMARY OF SITE RISKS
There are no remaining human health or environmental risks associated with direct exposure to
the surface soils because all contaminated soil from the surface to a depth of at least 4 feet was
removed, and the off-site soil used to backfill the excavation prevents direct exposure to the
remaining areas of deeper soil contamination. The remaining native soil underlying the backfill
material has contaminant levels that are less than the EPA Region 6 Human Health Media-
Specific Screening Levels for Residential Exposure. These screening levels are described in the
attached Statement of Basis.
The remaining soil contamination below 4 feet is not expected to result in any significant
ecological risk. For an ecological risk to exist, there must be a complete exposure pathway
where a contaminant can travel from a source to an ecological receptor, and be taken up by the
receptor by one or more exposure routes. The backfill material placed at the drum burial site
prevents any significant exposure of ecological receptors to the contaminants remaining below 4
feet.
Table 1 below lists the remaining specific contaminants present below a depth of 4 feet and the
corresponding human-health based Screening Levels.
TABLE 1
Contaminant
Acetone
Benzene
Ethyl Benzene
Methyl Ethyl Keytone
Toluene
Xylene
Maximum Remaining Soil
Concentration - mg/kg
(sample number)
79 (sample CS-5)
0.017 (sample CS-9)
0.010 (sample CS-5)
0.290 (sampk CS-5)
0.048 (sampk CS-5)
0.058 (sampk CS-5)
EPA Region 6 Human Health
Residential Soil
Screening Level - mg/kg
1,600
0.680
230
7,300
520
210
PUBLIC PARTICIPATION
The public comment period was held from August 13, 2001, to September 15, 2001. No
comments were received regarding the proposal for a "no further action" remedy.
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FUTURE ACTIONS
None
DECLARATION
Based on the previous excavation and removal of contaminated soil, and on the Administrative
Record compiled for this corrective action, the actions completed are appropriate and protective
of health and the environment, pursuant to Section 7003 of RCRA, 42 U.S.C. Section 6973.
(original signed by)
Samuel Coleman, P.E., Director Date
Compliance Assurance and
Enforcement Division
U.S. Environmental Protection Agency - Region 6
Dallas, Texas
Administrative Record Index
Statement of Basis
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