[Federal Register Volume 63, Number 191 (Friday, October 2, 1998)]
[Proposed Rules]
[Pages 53005-53008]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-26462]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 300

[FRL-6171-6]


National Oil and Hazardous Substances Pollution Contingency Plan; 
National Priorities List

AGENCY: Environmental Protection Agency.

ACTION: Notice of intent for partial deletion of the Rocky Mountain 
Arsenal National Priorities List Site from the National Priorities 
List; request for comments.

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SUMMARY: The Environmental Protection Agency (EPA) Region 8 announces 
its intent to delete the western tier parcel of the Rocky Mountain 
Arsenal National Priorities List Site (RMA/NPL Site) On-Post Operable 
Unit (OU) 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). This partial deletion of the RMA/NPL Site 
is proposed in accordance with 40 CFR 300.425(e) and Notice of Policy 
Change: Partial Deletion of Sites listed on the National Priorities 
List (November 1, 1995).
    EPA bases its proposal to delete the western tier of the RMA/NPL 
Site on the determination by EPA and the State of Colorado, through the 
Colorado Department of Public Health and Environment (CDPHE), that all 
appropriate actions under CERCLA have been implemented to protect human 
health, welfare and the environment and that no further response action 
by responsible parties is appropriate.
    This partial deletion pertains only to the western tier of the On-
Post OU of the RMA/NPL Site and does not include the rest of the On-
Post OU or the Off-Post OU. The rest of the On-Post OU and the Off-Post 
OU will remain on the NPL and response activities will continue at 
those OUs.

DATES: Comments concerning this proposed partial deletion may be 
submitted on or before November 2, 1998.

ADDRESSES: Comments may be mailed to: Rob Henneke, Community 
Involvement Coordinator (8OC), U.S. EPA, Region 8, 999 18th Street, 
Suite 500, Denver, Colorado, 80202-2466, 1-800-227-8917 or (303) 312-
6734.

[[Page 53006]]

    Comprehensive information on the RMA/NPL Site, as well as 
information specific to this proposed partial deletion, is available 
through EPA's Region 8 office in Denver, Colorado. Documents are 
available for viewing by appointment from 8:00 a.m. to 4:00 p.m., 
Monday through Friday excluding holidays by calling (303) 312-7287. The 
Administrative Record for the RMA/NPL Site and the Deletion Docket for 
this partial deletion are maintained at the Joint Administrative 
Records Document Facility, Building 135, Room 16, 72nd and Quebec 
Streets, Commerce City, Colorado 80022, (303) 289-0362.

FOR FURTHER INFORMATION CONTACT: Ms. Laura Williams, Remedial Project 
Manager (8EPR-F), U.S. EPA, Region 8, 999 18th Street, Suite 500, 
Denver Colorado, 80202-2466, (303) 312-6660.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Introduction
II. NPL Deletion Criteria
III. Deletion Procedures
IV. Basis for Intended Partial Site Deletion

Appendix

A. Deletion Docket
B. Site Coordinate Boundaries

I. Introduction

    The United States Environmental Protection Agency (EPA) Region 8 
announces its intent to delete the western tier parcel of the Rocky 
Mountain Arsenal National Priorities List (RMA/NPL Site), Commerce 
City, Colorado, from the National Priorities List (NPL) and requests 
comment on this proposed action. The NPL constitutes Appendix B of the 
National Oil and Hazardous Substances Pollution Contingency Plan (NCP), 
40 CFR part 300, which EPA promulgated pursuant to section 105 of the 
Comprehensive Environmental Response, Compensation and Liability Act 
(CERCLA), 42 U.S.C. 9605. EPA identifies sites that appear to present a 
significant risk to public health or the environment and maintains the 
NPL as the list of those sites. Sites on the NPL may be the subject of 
remedial actions financed by the Hazardous Substance Superfund (Fund). 
This partial deletion of the Site is proposed in accordance with 40 CFR 
300.425(e) and Notice of Policy Change: Partial Deletion of Sites 
Listed on the National Priorities List (60 FR 55466 (Nov. 1, 1995)). As 
described in 40 CFR 300.425(e)(3), portions of a site deleted from the 
NPL remain eligible for further remedial actions if warranted by future 
conditions.
    EPA will accept comments concerning its intent for partial deletion 
of the RMA/NPL Site for thirty days after publication of this document 
in the Federal Register.
    Section II of this document explains the criteria for deleting 
sites from the NPL. Section III discusses the procedures that EPA is 
using for this proposed partial deletion. Section IV discusses the 
western tier of the RMA/NPL Site and explans how it meets the deletion 
criteria.

II. NPL Deletion Criteria

    The NCP establishes the criteria that EPA uses to delete sites from 
the NPL. In accordance with 40 CFR 300.425(e), sites may be deleted 
from the NPL where no further response is appropriate to protect public 
health or the environment. In making such a determination pursuant to 
Sec. 300.425(e), EPA will consider, in consultation with the State, 
whether any of the following criteria have been met:
     Section 300.425(e)(1)(i). Responsible parties or other 
persons have implemented all appropriate response actions required; or
     Section 300.425(e)(1)(ii). All appropriate Fund-financed 
response under CERCLA has been implemented, and no further response 
action by responsible parties is appropriate; or
     Section 300.425(e)(1)(iii). The remedial investigation has 
shown that the release poses no significant threat to public health or 
the environment and, therefore, taking remedial measures is not 
appropriate.
    A partial deletion of a site from the NPL does not affect or impede 
EPA's ability to conduct CERCLA response activities for portions not 
deleted from the NPL. In addition, deletion of a portion of a site from 
the NPL does not affect the liability of responsible parties or impede 
agency efforts to recover costs associated with response efforts. The 
U.S. Army and Shell Oil company will be responsible for all future 
remedial actions required at the area deleted if future site conditions 
warrant such actions.

III. Deletion Procedures

    Upon determination that at least one of the criteria described in 
Sec. 300.425(e) of the NCP has been met, EPA may formally begin 
deletion procedures. The following procedures were used for this 
proposed deletion of the western tier of the RMA/NPL Site:
    (1) EPA has recommended the partial deletion and has prepared the 
relevant documents.
    (2) The State of Colorado, through the CDPHE, has concurred with 
publication of this notice of intent for partial deletion.
    (3) Concurrent with this national Notice of Intent for Partial 
Deletion, a local notice has been published in a newspaper of record 
and has been distributed to appropriate federal, State, and local 
officials, and other interested parties. These documents announce a 
thirty (30) day public comment period on the deletion package, which 
ends on November 2, 1998, based upon publication of this document in 
the Federal Register and a local newspaper of record.
    (4) EPA has made all relevant documents available at the 
information repositories listed previously for public inspection and 
copying.
    Upon completion of the thirty calendar day public comment period, 
EPA Region 8 will evaluate each significant comment and any significant 
new data received before issuing a final decision concerning the 
proposed partial deletion. EPA will prepare a responsiveness summary 
for each significant comment and any significant new data received 
during the public comment period and will address concerns presented in 
such comments and data. The responsiveness summary will be made 
available to the public at the EPA Region 8 office and the information 
repository listed above and will be included in the final deletion 
package. Members of the public are encouraged to contact EPA Region 8 
to obtain a copy of the responsiveness summary. If, after review of all 
such comments and data, EPA determines that the partial deletion from 
the NPL is appropriate, EPA will publish a final notice of partial 
deletion in the Federal Register. Deletion of the western tier of the 
RMA/NPL Site does not actually occur until a final notice of partial 
deletion is published in the Federal Register. A copy of the final 
partial deletion package will be placed at the EPA Region 8 office and 
the information repository listed above after a final document has been 
published in the Federal Register.

IV. Basis for Intended Partial Site Deletion

    The following information provides EPA's rationale for deletion of 
the western tier of the RMA/NPL Site from the NPL and EPA's finding 
that the proposed final deletion satisfies 40 CFR 300.425(e) 
requirements:

Background

    The On-Post OU of the RMA/NPL Site encompasses 27 square miles in 
southern Adams County, Colorado, approximately 8 miles northeast of the 
city of Denver. The Rocky Mountain Arsenal was established in 1942 by 
the

[[Page 53007]]

U.S. Army, and was used to manufacture chemical warfare agents and 
incendiary munitions for use in World War II. Prior to this, the area 
was largely undeveloped ranch and farm land. Following the war and 
through the early 1980s, the facilities continued to be used by the 
Army. Beginning in 1946, some facilities were leased to private 
companies to manufacture industrial and agricultural chemicals. Shell 
Oil Company, the principal lessee, primarily manufactured pesticides 
from 1952 to 1982. After 1982, the only activities at the Arsenal 
involved remediation.
    By the late 1950s, complaints of ground water pollution north of 
the RMA/NPL Site began to surface. Common industrial and waste disposal 
practices used during these years resulted in contamination of 
structures, soil, surface water, and ground water. As a result of this 
contamination, the Arsenal was proposed for inclusion on the NPL in 
July 1987. On February 17, 1989, an interagency agreement--referred to 
as a Federal Facility Agreement (FFA)--formalizing the process 
framework for selection and implemention of cleanup remedies at the 
RMA/NPL Site, was signed by the Army, Shell Oil Company, EPA, U.S. 
Department of the Interior, U.S. Department of Justice, and the Agency 
for Toxic Substances and Disease Registry.

Western Tier of the On-Post OU

    A remedial investigation (RI) completed in January 1992 studied 
each of the five environmental media at the RMA/NPL Site, including 
soils, water, structures, air, and biota. Based upon evidence gathered 
during the RI, information on the western tier of the RMA/NPL Site 
indicated the western tier area was exposed to minimal or no 
contamination and is considered a ``non-source'' area. A structures 
survey program identified eight structures within the western tier.
    Several ground water plumes below the western tier parcel have been 
identified but are not attributable to the RMA/NPL Site. Because the 
ground water does not meet drinking water standards, the Klein Water 
Treatment Facility was built in 1989--prior to completion of the RI--to 
treat the ground water contamination that is now known to originate 
from non-RMA/NPL sources. The Klein Water Treatment Facility is located 
within the area to be deleted; however, its continued operation, and 
associated 5-year review requirements, have been incorporated as part 
of the Chemical Sales Company Superfund Site.
    The Irondale Containment System (ICS) was constructed during 
development of the RI/FS as an interim response action (IRA). The ICS 
is partially located on the western tier and was installed to extract 
and treat ground water emanating from the Rail Yard and the Motor Pool 
areas which are in close proximity to the western tier.
    A feasibility study (FS) was finalized in October 1995 and a 
proposed plan prepared and presented to the public in October 1995 as 
well. On June 11, 1996, the On-Post Record of Decision (ROD) was signed 
by the Army, EPA, and the State of Colorado. The ROD specified no 
remedial action for soil within the western tier of the On-Post OU 
since the soil does not pose a risk to humans or biota. The remedy for 
structures included the dismantling of three of the eight structures 
found on the western tier. The selected ground water remedy consisted 
of continued operation of the ICS.

Community Involvement

    Since 1988 each of the Parties has made extensive efforts to ensure 
that the public is kept informed on all aspects of the cleanup program. 
More than 100 fact sheets about topics ranging from historical 
information to site remediation have been developed and made available 
to the public. Following the release and distribution of the draft 
Detailed Analysis of Alternatives report (a second phase of the FS), 
the Army held an open house for about 1,000 community members. The open 
house provided opportunity for individual discussion and understanding 
of the various technologies being evaluated for cleanup of RMA/NPL.
    The Proposed Plan for the On-Post OU was released for public review 
on October 16, 1995. On November 18, 1995 a public meeting was held, 
attended by approximately 50 members of the public, to obtain public 
comment of the Proposed Plan. As a result of requests at this meeting, 
the period for submitting written comments on the plan was extended one 
month, concluding on January 19, 1996. No public comments were received 
on the alternatives presented for the western tier of the On-Post OU.

Current Status

    Of the three structures slated for demolition, one was determined 
to no longer exist (a building foundation), and the other two 
structures (survey tower and septic tank) were demolished in October 
1997. Since the ROD was signed, three structures referred to as 
``vaults'' were found in section 9 of the western tier parcel. These 
structures were used for housing antennae associated with the Titan I 
Missile system deployed in northern Colorado during the late 1950s 
through the mid-1960s. Evaluation of the vaults confirmed that no 
radiological, chemical or biological materials were utilized in these 
structures. The vaults were removed from the western tier during the 
week of July 20, 1998.
    The ICS extraction wells have met the ROD shut-off criteria and 
were shut down on October 1, 1997. Extraction wells for the Motor Pool 
IRA have also met shut-off criteria; therefore, the ICS facility is 
currently operated solely to treat contaminated ground water which is 
piped from the Rail Yard IRA and not associated with the western tier 
parcel. Monitoring of the ground water aquifer previously treated 
through the ICS extraction wells, as required by the ROD, has been 
incorporated into the sitewide monitoring program.
    Use of the ground water below the western tier for potable drinking 
purposes is prohibited by the FFA, the RMA National Wildlife Refuge Act 
of 1992, and the ROD; and will continue to be prohibited even after 
portions of the western tier are sold. Additional prohibitions imposed 
by the FFA, Refuge Act, and ROD include the use of the western tier 
parcel for residential, industrial, and agricultural purposes, for 
hunting or fishing for consumptive purposes, and the use of any future 
surface water as a potable source.
    Based on the extensive investigations and risk assessment performed 
for the western tier of the RMA/NPL Site, there are no further response 
actions planned or scheduled for this area. This remedy for soil and 
structures does not result in hazardous substances remaining at the 
site above health-based levels with respect to anticipated uses of and 
access to the site, which are limited under the Federal Facility 
Agreement, Rocky Mountain Arsenal National Wildlife Refuge Act and the 
ROD. All completion requirements for the western tier of the On-Post OU 
have been achieved as outlined in OSWER Directive 9320.2-3A. Therefore, 
there are no requirements for a five-year review or operation and 
maintenance.
    EPA, with concurrence from the State of Colorado, has determined 
that all appropriate CERCLA response actions have been completed at the 
western tier parcel of the RMA/NPL Site to protect public health and 
the environment and that no further response action by responsible 
parties is required. Therefore, EPA proposes to delete the western tier 
of the On-Post OU of the RMA/NPL Site from the NPL.


[[Page 53008]]


    Dated: September 25, 1998.
Kerrigan Clough,
Acting Regional Administrator, Region 8.
[FR Doc. 98-26462 Filed 10-1-98; 8:45 am]
BILLING CODE 6560-50-P