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FORWARD LANDFILL NON-WATER CORRECTIVE ACTION PLAN groundwater elevations are observed during the winter/spring and lowest levels in the summer/fall. Groundwater elevations typically range from about-10 feet relative to MSL on the southern (Forward Unit)portion of the landfill to about-25 feet relative to MSL on the northern (Austin Unit)portion of the landfill. Data acquired by GLA between 2003 and 2009 indicates that, with rare exceptions, the groundwater flows in a north to northeasterly direction at a gradient between 0.001 and 0.003ft/ft. Although a broad range of hydraulic conductivity values have been assigned to the formational materials (e.g., clay, silt and sand)within the Victor Formation, slug tests performed in four wells at the Forward Landfill, resulted in hydraulic conductivity values of 2E-02 to 2E-03 cm/sec for the uppermost aquifer beneath the landfill. Based on the maximum hydraulic conductivity value of 2E-02 cm/sec, a hydraulic gradient of 0.003, and an estimated effective porosity of 0.2, the maximum groundwater velocity beneath the Forward Landfill is estimated to be approximately 0.85 feet per day. 2.3 SURFACE WATER HYDROLOGY The South Fork of South Littlejohns Creek flows within confining levees in a southwesterly direction along the southern edge of the Forward Unit and along the south side of the southern expansion area of the site. Similarly, the North Branch of the South Fork of Littlejohns Creek flows southwesterly along the northern side of the Austin Unit. The majority of flow from these drainages, although controlled by the flood control district, is generated from the surrounding agricultural activities and occurs during and after relatively heavy periods of precipitation. Within the Forward Landfill, site run-on and runoff is channeled to on-site storm water/sedimentation ponds. 3.0 LANDFILL CONFIGURATION This section of the NWCAP describes the existing landfill configuration, existing and future closure design, surface water control systems, and environmental control systems. 3.1 EXISTING LANDFILL Forward Landfill consists of a number of WMUs. The labeling of the WMUs has occurred in conjunction with site development,but is somewhat complicated by several overlapping units. The site includes the approximately 123-acre original disposal area of the former Austin Road Sanitary Landfill, which, unlike more recently constructed areas of Forward, does not contain a base liner or leachate collection and removal system(LCRS). M:\2011-0128\NWFA REPORT.DOCX 4 Geo-Logic Associates