WORK PLANS - Laserfiche WebLink

Home Browse Search

' water standards (20,000 pCi/1). A major investigation was initiated that included' a search of records concerning tritium use, disposal, and previous analyses, and a survey of tritium levels in soil, vegetation, and water in contaminated and potentially ' contaminated areas. To date, a source of tritium has been identified in the B850 area, and a tritium plume in a perched ground water zone has been traced from B850 along Doall Road to the EFA. By December 1988, LLNL plans to: ' 1. Investigate possible additional sources of tritium in the area of the EFA/B850. ' 2. Determine the vertical and horizontal extent of tritium in ground water in the area. ' Procedure To complete the remedial investigation of the EFA/13850, LLNL intends to install ' at least four additional monitoring wells to define the limits of the tritium plume emanating from the B850 area. The wells will be completed in the perched water- bearing zone along Doall Road and south of Pit 2 in the EFA. The wells will be ' constructed and developed according to LLNL protocol as described previously. Water samples will be collected quarterly and analyzed for tritium. In addition, three piezo- meters will be installed in the alluvium along Doall Road to provide for measurement of ground water levels during the rainy season. The Elk Ravine Fault will be examined both ' geophysically and hydrologically to evaluate its control on ground water movement. Results of testing will be employed in computer modeling to evaluate plume movement. ' Preparation of a feasibility study will begin in December 1988, after the remedial investigation is complete. TASK 9 - REMEDIAL ACTION AT THE EAST FIRING AREA/13850 Remedial action, if required, will begin in March 1990; a work plan will be prepared following completion of a feasibility study. ' TASK 10 - REMEDIAL INVESTIGATION/FEASIBILITY STUDY AT THE HIGH EXPLOSIVES PROCESS AREA ' Purpose and Rationale The purpose of this task is to complete the remedial investigation of HE in ground ' water at the HE Process Area. This will be completed by December 1988, and a feasibility study, if required, will be completed by December 1989. In 1987, the HE compound RDX was detected in the regional water-bearing zone in two monitoring wells ' near Buildings 815 and 817; RDX was also detected in a shallow water-bearing zone in an adjacent monitoring well at Building 815. Concentrations of RDX ranged from 30 to 190 ppb. The source and distribution of the RDX is unknown. By December 1988, LLNL ' plans to: 1. Investigate the source(s) of HE detected in soil and ground water in the HE Process Area. ' -8-