02-19520. Floodplain and Wetlands Statement of Findings for the Proposed Deactivation and Demolition of the Zone 13 Sewage Treatment Plant at the Pantex Plant, Amarillo, TX

AGENCY:

Department of Energy (DOE).

ACTION:

Floodplain and wetlands statement of findings.

SUMMARY:

This is a Floodplain and Wetlands Statement of Findings for the demolition of a decommissioned sewage treatment plant located on the Pantex Plant in Carson County, 17 miles northeast of Amarillo, Texas, in accordance with 10 CFR part 1022, Compliance with Floodplain/Wetlands Environmental Review Requirements. A floodplain and wetlands assessment was conducted that evaluated the potential impacts of this project. The floodplain and wetlands assessment describes the possible effects, alternatives, and measures designed to avoid or minimize potential harm to the floodplain and wetlands or their flood storage potential. DOE will allow 15 days of public review after publication of the Statement of Findings before implementation of the Proposed Action.

FOR FURTHER INFORMATION CONTACT:

Brenda G. Finley, Public Affairs Officer, U.S. DOE/NNSA, Office of Amarillo Site Operations, P.O. Box 30020, Amarillo, Texas 79120-0020, [phone], [phone] (FAX).

For Further Information on General DOE Floodplain/Wetlands Environmental Review Requirements, Contact: Carol M. Borgstrom, Director, Office of NEPA Policy and Compliance, U.S. Department of Energy, 1000 Independence Avenue, SW., Washington, DC 20585, [phone], [phone].

SUPPLEMENTARY INFORMATION:

A notice of Floodplain and Wetlands Involvement for the Proposed Deactivation and Demolition of the Zone 13 Sewage Treatment Plant at the Pantex Plant was published in the Federal Register on April 15, 2002 (67 FR 18182); and, subsequently, a floodplain and wetlands assessment was prepared. The floodplain and wetlands assessment documented the floodplain and wetlands communities that have the potential to be affected by the demolition of the Zone 13 Sewage Treatment Plant. Alternatives considered include: (1) removing and disposing of abandoned equipment and piping; razing the buildings, roads, and associated structures; disposing of all waste; returning the land to the original grade, and re-establishing vegetation (the Preferred Alternative), and (2) no action.

With the Preferred Alternative, some minor short-term impacts could occur during demolition and grading, which would be associated with stormwater runoff and erosion of soil particles. To mitigate these potential effects, erosion control measures will be installed during demolition and grading activities; and will remain in place until vegetative cover is established on 75 percent of the disturbed area. Potential long-term impacts to the wetland are associated with contaminants of concern entrained in building materials or sediments confined to below grade sumps. Because these materials are currently confined, and can be well controlled during demolition, the potential for being transported to the wetlands is limited to receding floodwaters that could inundate the area during demolition. To mitigate this potential negative effect, the existing tailwater pit will be used to control rising waters; and may have a pump installed to keep water from building up in the tailwater pit. The tailwater pit has enough volume to contain 1.26 acre feet of stormwater. The controls on the tailwater pit will remain operational until demolition activities are completed. Equipment and materials used during demolition and grading will be staged in an area outside the floodplain. This proposed action complies with State and local floodplain requirements.

Issued in Amarillo, Texas, on July 10, 2002.

Jerry S. Johnson,

Associate Director for Environmental & Site Engineering Programs.