VAPOR EXTRACTION VOLUNTARY CORRECTIVE MEASURE AT THE CHEMICAL WASTE LANDFILL, SANDIA NATIONAL LABORATORIES/NEW MEXICO

RCRA corrective action. Starting in 1962, bulk liquids, bulk solids, and containerized wastes were placed in unlined pits excavated in permeable sediment to approximately 3.7 meters (m) below ground surface (bgs). Disposal records were kept for the period 1975 through the end of pit disposal operations in 1981. By extrapolation, it is estimated that a total of over 363,000 kilograms (kg) of organic chemical wastes, including approximately 182,000 kg of volatile organic compounds (VOCs) were disposed. Over 100 priority pollutants have been detected in the sediment and soil gas beneath the CWL. Groundwater located at approximately 152-m bgs is impacted by low concentrations of chlorinated solvents, principally trichloroethene (TCE). In May 1995, SNL/NM determined that the cycle of data collection for the RCRA Facility Investigation could not be adequately managed and opted for a pro-active strategy. It was determined that Voluntary Corrective Measures (VCMs), in the form of vapor extraction (VE) and landfill excavation (LE) VCMs, would serve to efficiently remove important sources of contamination, eliminate exposure pathways, and significantly streamline final corrective actions. The Closure Plan provides for the possibility of one or more VCMs, although specifics were not written into the plan. By December 1995, SNL/NM and the New Mexico Environmen