[Federal Register Volume 59, Number 114 (Wednesday, June 15, 1994)] [Unknown Section] [Page 0] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 94-14552] [[Page Unknown]] [Federal Register: June 15, 1994] ----------------------------------------------------------------------- DEPARTMENT OF ENERGY Notice of Floodplain and Wetlands Involvement for Hydrogeological Characterization Studies at the Pantex Plant, Amarillo, TX AGENCY: Department of Energy (DOE). ACTION: Notice of floodplain and wetlands involvement. ----------------------------------------------------------------------- SUMMARY: DOE proposes to conduct hydrogeological characterization studies, some of which would be within floodplains and wetlands within the borders of or surrounding the Pantex Plant in Carson County, 17 miles northeast of Amarillo, Texas. In accordance with 10 CFR part 1022, DOE will prepare a floodplain and wetlands assessment and will perform this proposed action in a manner so as to avoid or minimize potential harm to or within the affected floodplain and wetlands. DATES: Comments on the proposed action must be received by June 30, 1994. ADDRESSES: Comments concerning this Notice should be addressed to: Floodplain and Wetlands Comments, Tom Walton, Public Affairs Office, U.S. Department of Energy, Amarillo Area Office, P.O. Box 30020, Amarillo, Texas 79177, (806) 477-3120, (806) 477-3185 (Fax). Information on this proposed action, including a map of proposed sampling locations, is also available. FOR FURTHER INFORMATION CONTACT: Information on general DOE floodplain and wetlands environmental review requirements is available from: Carol M. Borgstrom, Director, Office of NEPA Oversight, U.S. Department of Energy, 1000 Independence Avenue SW., Washington, DC 20585, (202) 586- 4600, (800) 472-2756. SUPPLEMENTARY INFORMATION: DOE proposes to conduct a hydrogeological characterization study within floodplains and wetlands on and surrounding the Pantex Plant. The characterization studies would be conducted in support of the Permit for Industrial Solid Waste Management Site issued by the Texas Water Commission (now known as the Texas Natural Resources Conservation Commission) as part of DOE's effort to determine the nature and extent of any environmental contamination resulting from Pantex operations. On-site activities would occur within Solid Waste Management Units (SWMU) 6 (Playa Basin 1), SWMU 7 (Playa Basin 2), SWMU 8 (Playa Basin 3), SWMU 9 (Playa Basin 4), and SWMU 10 (Pantex Lake). Off-site activities would occur at Playa 5, located 2 miles southwest, and the Playa owned by the Texas Department of Criminal Justice, located 4.5 miles northeast of the Pantex Plant. On- and off-site activities would be conducted by the State of Texas under an Agreement in Principle with the DOE. The characterization studies occurring near or in the floodplain and wetlands would include: 1. Drilling boreholes for the purpose of collecting core samples from the playa basins. 2. Routine sampling, downloading, and maintenance of installed instrumentation. 3. Conducting soil gas surveys in and near the floodplain and wetlands. 4. Seismic survey activities to define playa basin geologic structure. 5. Trenching in or near the floodplain and wetlands for the installation of soil moisture instrumentation such as: thermocouple psychrometers, tensiometers, and Time Domain Reflectometers (TDR). 6. Trenching in and near the floodplain and wetlands to perform chemical (food coloring) tracer tests. 7. Surveying activities to define playa basin topography. A more specific description of the seven activities listed above follows: 1. Borehole drilling would involve driving a drilling rig and a portable core sample laboratory to the site, drilling the boreholes, and collecting the core samples as the drilling progresses. The boreholes would be either closed by back-filling with the cuttings, or completed as soil solution sampling wells or neutron probe access tubes. The core sample borings will not exceed 120 feet in depth and the soil solution sampling wells and neutron probe access tubes would not exceed a maximum depth of 80 feet. Because the playa basin is ephemeral, drilling activities would only occur during the dry cycle of the playa. 2. The routine sampling, downloading, and maintenance of installed instrumentation would involve driving a utility vehicle to the site. Some instrumentation would be installed in the wetland and would involve entering the playa during the wet season to take samples and download data. Personnel entering wet areas of the playa would enter on foot to avoid undue impact to the floodplain and wetlands. 3. Soil gas surveys would be conducted during both dry and wet seasons in the playas and would involve driving a utility vehicle near the playa floor to download soil gas to a portable gas chromatograph. Personnel entering wet areas of the playa would enter on foot to avoid undue impact to the floodplain and wetlands. 4. Seismic survey activities would involve driving two utility vehicles and a tailer mounted weight-drop unit, used as an energy source, into the playa basin. This activity involves driving across the playa floor and can only be accomplished when the playa is completely dry, to minimize undue impact to the floodplain and wetlands. 5,6. Trenching in or near the floodplain and wetlands would involve driving a truck (larger than ton) and trailer mounted backhoe into the wetland areas to excavate the trenches. The trenches for the tracer tests would not exceed 3 meters in depth and would be the appropriate length and width to satisfy OSHA requirements. The trenches would remain open as long as the tracer tests are ongoing, and then would be backfilled and leveled. The trenches for the installation of the soil moisture instrumentation would not exceed 4.5 feet in depth and would involve installing TDR and psychrometer probes into the sidewall and endwall of the trench. These instrument trenches would be backfilled immediately after the probes are installed. Clean Water Act Section 404 permit authorization has been received for the trenching in these areas. 7. Surveying activities would involve driving a utility vehicle carrying equipment into the playa basin. The surveying would be done by personnel on foot to minimize any potential impact to the floodplain and wetlands. In accordance with DOE regulations for compliance with floodplain and wetlands environmental review requirements (10 CFR part 1022), DOE will prepare a floodplains and wetlands assessment for this proposed DOE action which may be incorporated into the appropriate National Environmental Policy Act documentation. After DOE issues the assessment, a floodplain statement of findings will be published in the Federal Register. Ralph G. Lightner, Director, Office of Southwestern Area Programs, Environmental Restoration. [FR Doc. 94-14552 Filed 6-10-94; 2:00 pm] BILLING CODE 6450-01-P