[Federal Register Volume 64, Number 138 (Tuesday, July 20, 1999)] [Notices] [Page 38899] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 99-18432] ----------------------------------------------------------------------- DEPARTMENT OF ENERGY Notice of Wetland Involvement for Interim Measures for the Mixed Waste Management Facility (MWMF) Groundwater at the Burial Ground Complex (BGC), Savannah River Site, Aiken, South Carolina
Agency
Savannah River Operations Office (SR), Department of Energy (DOE).
Action
Notice of wetland involvement.
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Summary
DOE-SR proposes to install a small metal sheet pile wall dam which would be positioned to impound about 0.49 hectares (1.2 acres) of water around and over the BGC southwest groundwater seepline. This action would be taken in cooperation with the South Carolina Department of Health and Environmental Control (SCDHEC) to reduce the amount of tritium contaminated water seeping to the surface from the BGC southwest plume and eventually discharging to Fourmile Branch, an onsite stream. This interim measure is intended to control the movement and discharge of contaminated groundwater until the final, more permanent corrective measure is taken. In accordance with 10 CFR 1022, DOE will prepare a wetland assessment and will perform this proposed action in a manner so as to avoid or minimize potential harm to or within the affected wetland.
Dates
Comments on the proposed action due on or before August 4, 1999.
Addresses
For further information, including a site map and/or copy of the wetland assessment, or to submit comments regarding this notice, contact A. R. Grainger, National Environmental Policy Act (NEPA) Compliance Officer, Savannah River Operations Office, Building 742-A, Room 185, Aiken, South Carolina 29808. The fax/phone number is (800) 881-7292. The e-mail address is nepa@srs.gov.
FOR FURTHER INFORMATION ON GENERAL FLOODPLAIN/WETLANDS ENVIRONMENTAL REVIEW REQUIREMENTS, CONTACT: Ms. Carol M. Borgstrom, Director, Office of NEPA Policy and Assistance (EH-42), U.S. Department of Energy, 1000 Independence Avenue, SW., Washington, DC 20585. Telephone (202) 586- 4600 or (800) 472-2756.
Supplementary Information
A groundwater contaminant plume has been detected and is emanating from the Old Radioactive Waste Burial Ground (ORWBG) which is located at the southwest corner of the BGC at SRS. Tritium-contaminated water from this southwest plume is seeping to the surface at areas along the Old F-Area Effluent Ditch (OFED). Currently, groundwater that emanates from this seep combines with surface drainage from the immediate area to form a small stream in the southern portion of the OFED. Eventually, this stream mixes with F-Area discharge water which then flows into Fourmile Branch, an onsite stream. DOE-SR proposes to install a small metal sheet pile wall dam [approximately 1.5 to 2.1 meters (5 to 7 feet) high and 100.6 meters (330 feet) long] which would be positioned to impound about 0.49 hectares (1.2 acres) of water around and over the BGC southwest groundwater seepline. The impounded 0.49 hectares (1.2 acres) has been determined to be jurisdictional wetlands. The proposed action is not within the 100-year or baseline floodplain. This action would be taken in cooperation with SCDHEC to reduce the amount of tritium-contaminated water seeping to the surface and eventually discharging to Fourmile Branch. The impoundment would retard surface water flow to Fourmile Branch by increasing travel time, thereby mitigating the discharge of tritium-contaminated water. In addition, a drip irrigation system is being evaluated to enhance the effectiveness of the interim measure. This feature would further minimize discharges to Fourmile Branch by pumping impounded water behind the dam during peak flow conditions to upstream locations. The interim measure will also address the remediation of volatile organic compounds (VOCs) from ``hotspot'' regions associated with the southwest plume area. Airlift recirculation wells will be installed in ``hotspot'' regions where concentrations of VOCs have routinely exceeded drinking water standards. Airlift recirculation wells provide a means for removing VOCs from contaminated groundwater, through a combination of in place air stripping and airlift pumping processes. This interim measure is intended to control the movement and discharge of contaminated groundwater until the final, more permanent corrective measure is taken. Undertaking the proposed action will not affect DOE's ability to fully evaluate reasonable alternatives for the final action. An Environmental Assessment (EA) will also evaluate several alternatives to the proposed action. In accordance with DOE regulations for compliance with wetland environmental review requirements (10 CFR 1022), DOE-SR will prepare a wetland assessment for this proposed DOE action. The assessment will be included in the EA (DOE/EA-1302) that is being prepared for the proposed action in accordance with the requirements of NEPA.
Issued in Aiken, SC, on July 7, 1999. Lowell E. Tripp, Director, Engineering and Analysis Division, Savannah River Operations Office. [FR Doc. 99-18432 Filed 7-19-99; 8:45 am] BILLING CODE 6450-01-P