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Landfill. This is based on the erratic pattern of low VOC detections, the relative long list of VOCs that are detected, the detection of VOCs in both upgradient and downgradient monitoring wells, and the consistency of inorganic water quality in both upgradient and downgradient wells near the site. GLA concluded that the potential impacts associated with the VOCs in the groundwater appear to be small because the concentrations of VOCs are well below drinking water standards and the absence of VOCs at offsite monitoring locations indicate that VOCs degrade or disperse within a relatively short distance of the landfill boundary. The decomposition process that produces landfill gas results in positive pressure within the waste mass, which in some cases leads to gas flux through the bottom or around the edges of the landfill. Landfill gas impacts to groundwater are caused by gas contacting groundwater, where some constituents then dissolve into the water. Forward has enhanced its gas extraction system beyond the requirements of air pollution control regulations in order to reduce gas pressure within the waste mass, and the attendant possibility of gas migration to surrounding soils and groundwater. At the existing Austin Unit of the Landfill (formerly the Austin Road Landfill), a Solid Waste Assessment Test in 1989 found a significant groundwater quality impact. Several VOCs were found in the downgradient monitoring wells. An evaluation monitoring program (EMP) was implemented and confirmed VOC impacts along the entire downgradient edge of the landfill, in the first encountered water bearing zone, with the chlorinated hydrocarbon impacted groundwater extending laterally as far as 1,000 feet downgradient of the edge of the landfill. A corrective action program (CAP) was proposed in 1991 to address the chlorinated hydrocarbon impact to groundwater. The plan was approved by the RWQCB in June 1991 and involves the following actions: • Reduction of leaching of chlorinated hydrocarbons into the groundwater by checking incoming loads into the landfill for hazardous materials and implementing measures to reduce storm-water infiltration into the refuse; • Extraction of groundwater from two wells to reduce the off-site migration of chlorinated hydrocarbons, which began operation in 1994; Forward Landfill- Project Description 2-14 BRYAN A.STIRRAT&ASSOCIATES J:\Allied\Forward\2007.0018 Lateral Expansion\Reports\Proj Descrip\021308 Final Proj Des\Sec 2.doc:2/13/2008)