Approval of the Amendment to the Interim Site-Wide Record of Decision for the Pit 7 Complex at Lawrence Livermore National Laboratory Site 300

Approval of the Amendment to the Interim Site-Wide Record of Decision for the Pit 7 Complex at Lawrence Livermore National Laboratory Site 300

The project is the approval of the Amendment to the Interim Site-Wide Record of Decision (ROD) for the Pit 7 Complex, Lawrence Livermore National Laboratory (LLNL) Site 300. Site 300 is a federal facility operated for the U.S. Department of Energy (DOE) by the University of California, and was placed on the Federal National Priorities List in 1990. Site 300 is primarily a high-explosives test facility that supports the LLNL weapons program in research, development, and testing associated with weapons components. During past LLNL operations, a number of contaminants were released to the environment. From 1958 until 1988, debris from explosives tests was disposed in the Pit 7 Complex. The waste placed in the pits included wood, plastic, metal, and debris from tent structures, pea gravel, and exploded test assemblies that were contaminated with tritium and depleted uranium. The landfills periodically release tritium, uranium, and other contaminants to shallow groundwater. The Amendment to the Interim Site-Wide ROD, finalized in January 2007, identifies the preferred cleanup alternative for the Pit 7 Complex. Cleanup of the Pit 7 Complex involves four types of construction activities. These include installation of: a water diversion system; a groundwater treatment facility; wells; and roads. Each type of construction activity is described separately, below. Once construction is complete, the systems would be passive, and only require monthly visits from technicians for sampling and calibration.

Tracy

San Joaquin