[Federal Register Volume 61, Number 141 (Monday, July 22, 1996)]
[Proposed Rules]
[Pages 37876-37878]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-18180]
-----------------------------------------------------------------------
[[Page 37877]]
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 300
[FRL-5538-8]
National Oil and Hazardous Substances Pollution Contingency Plan;
National Priorities List
Agency: Environmental Protection Agency.
Action: Notice of intent to delete McChord Air Force Base Washrack
Treatment Area from the National Priorities List Update: Request for
comments.
-----------------------------------------------------------------------
SUMMARY: The Environmental Protection Agency (EPA), Region 10,
announces its intent to delete the McChord Air Force Base Washrack
Treatment Area (Washrack Treatment Area) Site from the National
Priorities List (NPL) and requests public comment on this proposed
action. The NPL constitutes Appendix B of 40 CFR part 300 which is the
National Oil and Hazardous Substances Pollution Contingency Plan (NCP),
which EPA promulgated pursuant to Section 105 of the Comprehensive
Environmental Response, Compensation, and Liability Act (CERCLA) of
1980, as amended. EPA and the State of Washington Department of Ecology
(Ecology) have determined that all appropriate remedial response to the
extent practicable has been taken and that the Site poses no
significant threat to public health or the environment. Therefore,
further remedial measures pursuant to CERCLA are not appropriate.
DATES: Comments concerning this Site may be submitted on or before
August 21, 1996.
ADDRESSES: Comments may be mailed to: Kathleen Stryker, Environmental
Protection Agency, 1200 Sixth Avenue, Mail Stop: ECL-115, Seattle,
Washington 98101.
Comprehensive information on this Site is available through the
Region 10 public docket which is available for viewing at the McChord
Air Force Base Washrack Treatment Area information repositories at the
following locations:
Pierce County Library, Lakewood Branch, 6300 Wildaire Road SW Lakewood,
WA 98499.
United States Environmental Protection Agency, Region 10 Office of
Environmental Cleanup--Records Center, Attn: Dawn Musgrove, 1200 Sixth
Avenue, Mail Stop, ECL-076, Seattle, Washington 98101.
FOR FURTHER INFORMATION CONTACT: Kathleen Stryker, U.S. EPA Region 10,
1200 Sixth Avenue, Mail Stop: ECL-115, Seattle, Washington 98101, (206)
553-1171.
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Introduction
II. NPL Deletion Criteria
III. Deletion Procedures
IV. Basis of Intended Site Deletion
I. Introduction
The Environmental Protection Agency (EPA) Region 10 announces its
intent to delete a site from the National Priorities List (NPL),
Appendix B of the National Oil and Hazardous Substances Contingency
Plan (NCP), 40 CFR part 300, and requests comments on this deletion.
EPA identifies sites on the NPL that appear to present a significant
risk to human health or the environment. As described in
Sec. 300.425(e)(3) of the NCP, sites deleted from the NPL remain
eligible for remedial actions in the unlikely event that conditions at
the site warrant such actions.
EPA plans to delete the McChord Air Force Base Washrack Treatment
Area Site (``Site'') in Tacoma, Washington, from the NPL.
EPA will accept comments on the plan to delete this Site until
August 21, 1996.
Section II of this document explains the criteria for deleting
sites from the NPL. Section III discusses procedures that EPA is using
for this action. Section IV discusses the Washrack Treatment Area Site
and explains how the Site meets the deletion criteria.
II. NPL Deletion Criteria
Section 300.425(e) of the NCP provides that ``releases'' (sites)
may be deleted from, or recategorized on the NPL where no further
response is appropriate. In making a determination to delete a site
from the NPL, EPA shall consider, in consultation with the state,
whether any of the following criteria have been met:
(i) Responsible parties or other parties have implemented all
appropriate response actions required;
(ii) All appropriate responses under CERCLA have been implemented,
and no further action by responsible parties is appropriate, or
(iii) The remedial investigation has shown that the release poses
no significant threat to public health or the environment and,
therefore, taking of remedial measures is not appropriate.
Even if a site is deleted from the NPL, where hazardous substances,
pollutants or contaminants remain at the site above levels that allow
for unlimited use and unrestricted exposure, EPA's policy is that a
subsequent review of the site will be conducted at least every five
years after the initiation of the remedial action at the site to ensure
that the site remains protective of public health and the environment.
In the case of the Washrack Treatment Area Site, hazardous substances
above health-based levels do not remain on the site, therefore,
periodic five-year reviews are not required. In addition, whenever
there is a significant release from a site deleted from the NPL, the
site may be restored to the NPL without the application of the Hazard
Ranking System.
III. Deletion Procedures
The following procedures were used for the intended deletion of
this Site: (1) The Air Force completed all appropriate response actions
required for the site. EPA Region 10 issued a memo to document that no
further active remedial response is necessary at the site thus
qualifying the Site for inclusion on the Superfund Site Construction
Completion List, and a final close out report that documents the
achievement of cleanup goals; (2) Ecology concurred with the proposed
deletion decision; (3) A notice has been published in the local
newspaper and has been distributed to appropriate federal, state, and
local officials and other interested parties announcing the
commencement of a 30-day public comment period on EPA's Notice of
Intent to Delete; and, (4) All relevant documents have been made
available for public review in the local Site information repositories.
Deletion of the Site from the NPL does not itself, create, alter or
revoke any individual rights or obligations. The NPL is designed
primarily for informational purposes to assist Agency management. As
mentioned in Section II of this Notice, 40 CFR 300.425(e)(3) states
that deletion of a site from the NPL does not preclude eligibility for
future response actions.
EPA's Regional Office will accept and evaluate public comments on
EPA's Notice of Intent to Delete before making a final decision. The
Agency will prepare a Responsiveness Summary if any significant public
comments are received.
A deletion occurs when the Regional Administrator places a final
action in the Federal Register. Generally, the NPL will reflect
deletions in the final update following the final action. Public
notices and copies of the Responsiveness Summary will be made available
to local residents by the Regional office.
IV. Basis for Intended Site Deletion
The following site summary provides the Agency's rationale for the
intention to delete this Site from the NPL.
[[Page 37878]]
Site Location and History
McChord Air Force Base (AFB) is an active 4,616-acre military
installation located seven miles south of downtown Tacoma. The Washrack
Treatment Area (WTA), a 22-acre area where airplanes were washed and
drained of fuel, is located within the northern industrial and
operational portion of the base along the western portion of the
instrument runway. The site includes the former washrack (now
inactive), two leach pits (now backfilled), an oil/water separator
(skimmer), storm drainage infiltration ditches (now backfilled) and a
layer of floating fuel on shallow groundwater in the vicinity.
The two Department of Defense (DOD) Installation Restoration
Program (IRP) sites that comprise the WTA (SD-54, the leach pits; and
DP-60, infiltration ditches) were originally identified during the 1982
Phase I record search (CH2MHIll. 1982) conducted by McChord. The phase
two IRP investigation (SAIC, 1985) measured low level organic
contamination at Site DP-60 and the adjacent IRP Site SD-54.
As a result of the IRP record search and investigation, further
studies were recommended to confirm contaminant characteristics and
distribution. The EPA designated Site SD-54 as the Washrack Treatment
Area in 1984 and nominated it for inclusion on the NPL. The site was
listed in 1987. In 1989 the Air Force entered into a three party
Federal Facilities Agreement (FFA) with Region X of the EPA and Ecology
for conducting an investigation and cleanup of contaminants posing an
unacceptable risk to human health and the environment.
A remedial investigation, which was completed in 1992, investigated
source areas for the floating fuel and evaluated the nature and extent
of contamination in all potentially affected media. Based on evaluation
of the RI and the baseline risk assessment, the EPA determined and
documented in the Record of Decision (ROD) for the WTA that no remedial
action under CERCLA was necessary for soil, surface water or sediment
to ensure protection of human health and the environment. The ROD
selected passive removal of the floating fuel to address the
unacceptable risk posed by benzene associated with the floating fuel
layer, and monitoring to evaluate the need for remediation of the
residual fuel in the soil.
A remedial design pilot study for recovery of the floating fuel or
Non-Aqueous Phase Liquids (NAPL) was performed in 1993 and 1994 to
determine if the layer of floating fuel could be removed. The NAPL
Pilot Test Study (EA Engineering, 1994) concluded that passive removal
of the fuel was not feasible due to the small amount of fuel present
and that original estimates of fuel available for recovery were
overestimates. The study also concluded that the soil was not a
significant continuing source of contamination to groundwater and that
there is an active population of bacteria present in the soil capable
of naturally degrading the petroleum.
In light of the findings of the Pilot Study an Explanation of
Significant Differences (ESD) was prepared. The ESD described the
results of the pilot study and the changes that were made to the ROD as
a result. The ESD changed the final remedy to a combination of natural
attenuation and long-term monitoring of the groundwater. Natural
attenuation consists in part of allowing the hydrocarbons in the
shallow groundwater to be consumed by the naturally occurring bacteria
present at the site and to allow the lighter portions of the
hydrocarbons to volatilize. The shallow groundwater below the floating
fuel would be monitored, as well as the shallow groundwater up- and
down gradient of the floating fuel.
The installation of one test trench and ten test pit observation
wells as part of the pilot test for the passive removal of the floating
fuel constituted the only active remedial action that occurred at the
site. EPA concurred in a March 1995 addendum to the ROD that no further
active remedial response under CERCLA is necessary at the WTA. This
addendum served to signify construction completion.
Eleven rounds of groundwater samples have been collected at the
floating fuel area since September 1990. All of the groundwater samples
were analyzed for the six compounds for which Remedial Action
Objectives (RAOs) were established in the ROD. With the exception of
total petroleum hydrocarbons (TPH), levels of these compounds detected
in the seven rounds conducted since completion of the ROD have been
consistently below the RAOs. Semi-annual monitoring reports conducted
since the ROD for the WTA are available in the site repository.
Public Participation
Community input has been sought by McChord Air Force Base
throughout the cleanup process for the Site. Community relations
activities have included public meetings prior to the signing of the
ROD, several public notices in local newspapers, and routine
publication of progress fact sheets. A copy of the Deletion Docket can
be reviewed by the public at the Pierce County Library, Lakewood Branch
or the EPA Region 10 Superfund Records Center. The Deletion Docket
includes this Notice, the ROD, ESD, Remedial Action Construction
Report, Memo documenting that no further remedial action is necessary,
and Final Site Close-Out Report. EPA Region 10 will also announce the
availability of the Deletion Docket for public review in a local
newspaper and informational fact sheet.
One of the three criteria for deletion specifies that EPA may
delete a site from the NPL if ``responsible parties or other persons
have implemented all appropriate response actions required''. EPA, with
the concurrence of Ecology, believes that this criterion for deletion
has been met. Ground water data from the Site confirm that the ROD
cleanup goals have been achieved. It is concluded that there is no
significant threat to human health or the environment and, therefore,
no further remedial action is necessary. Subsequently, EPA is proposing
deletion of this Site from the NPL. Documents supporting this action
are available from the docket.
Dated: July 8, 1996.
C. Findley,
Acting Regional Administrator, Region 10.
[FR Doc. 96-18180 Filed 7-19-96; 8:45 am]
BILLING CODE 6560-50-P
