2010-22747. National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List: Partial Deletion of the Rocky Mountain Arsenal Federal Facility

AGENCY:

Environmental Protection Agency.

ACTION:

Final rule.

SUMMARY:

The Environmental Protection Agency (EPA) Region 8 announces the deletion of portions of the On-Post Operable Unit (OU3), specifically the Central and Eastern Surface Areas including surface media and structures (CES), and the surface media of the Off-Post Operable Unit (OU4) (OPS) of the Rocky Mountain Arsenal Federal Facility (RMA) located in Commerce City, Colorado from the National Priorities List (NPL). The NPL, promulgated pursuant to section 105 of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980, as amended, is an appendix of the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). This partial deletion pertains to the surface media (soil, surface water, sediment) and structures (both former structures that have been demolished and structures retained for future use) within the CES and the surface media of the entire OPS. The rest of the On-Post OU, including groundwater below RMA that is west of E Street, and the groundwater that comprises the Off-Post OU will remain on the NPL and is not being considered for deletion as part of this action. Response activities will continue at those OUs. The EPA and the State of Colorado, through the Colorado Department of Public Health and Environment (CDPHE), have determined that all appropriate response actions under CERCLA, other than operation, maintenance, and five-year reviews, have been completed. However, the deletion of these parcels does not preclude future actions under Superfund.

DATES:

Effective Date: This action is effective September 13, 2010.

ADDRESSES:

EPA has established a docket for this action under Docket Identification No. EPA-HQ-SFUND-1987-0002. All documents in the docket are listed on the http://www.regulations.gov Web site. Although listed in the index, some information is not publicly available, i.e., Confidential Business Information or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy form. Publicly available docket materials are available either electronically through http://www.regulations.gov or in hard copy at the site information repositories. Locations, contacts, phone numbers and viewing hours are:

—EPA's Region 8 Superfund Records Center, 1595 Wynkoop Street, Denver, Colorado 80202-2466. Hours: 8 a.m. to 4 p.m. by appointment (call 303-312-6473), Monday through Friday, excluding legal holidays; and the

—Joint Administrative Records Facility, Rocky Mountain Arsenal, 5650 Havana Street, Building 129, Commerce City, Colorado 80022-1748. Hours: 12 p.m. to 4 p.m., Monday through Friday, excluding legal holidays, or by appointment (call 303-289-0983).

FOR FURTHER INFORMATION CONTACT:

Jennifer Chergo, Community Involvement Coordinator (8OC), U.S. Environmental Protection Agency, Region 8, 1595 Wynkoop Street, Denver, Colorado 80202-1129, 1-800-227-8917 or 303-312-6601; fax number: 303-312-7110; e-mail: [e-mail].

SUPPLEMENTARY INFORMATION:

The portion of the site to be deleted from the NPL is the surface media (soil, surface water, sediment) and structures (both former structures that have been demolished and structures retained for future use) within the CES and the surface media of the entire OPS. A Notice of Intent for partial Deletion for this Site was published in the Federal Register on June 17, 2010. The RMA Site-Specific Advisory Board (SSAB) requested additional time to adequately review the documentation. The public comment period for the NOIDp was extended through August 16, 2010 (75 FR 42361).

EPA received comment letters from seven organizations/individuals. Authors of five of the letters voiced their support for proceeding with the partial deletion based upon their confidence in the thoroughness of the cleanup activities conducted by the U.S. Army and Shell Oil Company; though one letter, from the Audubon Society of Greater Denver, was received after the public comment period closed. Authors of the remaining two letters were opposed to the proposed partial deletion of the CES and OPS. All public comments and EPA's responses are included in a Responsiveness Summary document available in both the docket, EPA-HQ-SFUND-1987-0002, at http://www.regulations.gov and in the local repositories listed above. Based on our responses to these comments, and in consultation with the State of Colorado through CDPHE, EPA has determined that all appropriate response actions under CERCLA, other than operation, maintenance, and five-year reviews, have been completed and it is appropriate to proceed with deletion of the CES and the OPS.

EPA maintains the NPL as the list of sites that appear to present a significant risk to public health, welfare, or the environment. Deletion of a site from the NPL does not preclude further remedial action. Whenever there is a significant release from a site deleted from the NPL, the deleted site may be restored to the NPL without application of the hazard ranking system. Deletion of portions of a site from the NPL does not affect responsible party liability, in the unlikely event that future conditions warrant further actions.

List of Subjects in 40 CFR Part 300

• Environmental protection
• Air pollution control
• Chemicals
• Hazardous waste
• Hazardous substances
• Intergovernmental relations
• Penalties
• Reporting and recordkeeping requirements
• Superfund
• Water pollution control
• Water supply

Dated: September 2, 2010.

Stephen S. Tuber,

Acting Regional Administrator, Region 8.