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3.3 Surface Water Monitoring Network Water quality in both the North Fork and South Fork of Littlejohns Creek is monitored quarterly at stations FSW-1, FSW-2, ASW -1, and ASW -2 (Figure 1). Historically, no VOCs have been detected in the surface water samples, and no indications of inorganic impacts to surface water have been observed. 3.4 Groundwater Treatment In response to the VOC impacts to groundwater at the Austin Unit, a groundwater extraction and treatment facility (GTF) was installed at the former Austin Road Landfill site in 1994 as part of an approved Corrective Action Program (CAP). The current GTF was designed to treat and discharge a maximum of 790,000 gallons per day of groundwater from two groundwater extraction wells (EW -1 and EW -2) along the northern perimeter of the Austin Unit, treated through an air stripper, and discharged to an infiltration pond (Figure 1). In 2009, two additional groundwater extraction wells (EW -3R and EW -4) were added to the GTF. Over the 2013 monitoring year, the GTF treated approximately 84,000,000 gallons of groundwater at an average rate of 230,000 gallons per day. 4.0 POTENTIAL WATER QUALITY IMPACTS Water quality impacts at waste management units (WMUs) are typically related to the following: surface water degradation associated with contact of refuse with surface water or liquid (leachate) and discharge from the WMU to surface waters; vadose zone degradation associated with either landfill gas (LFG) or moisture migration from the WMU; and groundwater degradation associated with WMU leachate or LFG migration to the water table. In accordance with 27CCR, Section 21750 (a), the following sections describe the anticipated avenues by which landfill constituents may be released to adversely impact water quality beneath and adjacent to the WMU. 4.1 Potential Surface Water Impacts Perhaps the most obvious means by which WMU fluids can impact waters of the state is by direct contact between surface waters and refuse. The presence of effective drainage controls at the Forward Landfill will minimize that potential condition. All wastes at the Forward Landfill facility are separated from the North Fork and South Fork of Littlejohns Creek by a levee system that has been designed to protect the site from the 1000 -year flood event. Accordingly, creek waters will not come in contact with wastes, and the only potential surface water impact is related to controlled run-off from the site. The surface water control system on the Forward Landfill is designed for a 1000 -year, 24-hour precipitation event. In addition, an alternative final cover system has been constructed for the northern slopes of the Austin Unit, and is seeded with native grasses to minimize erosion. D:\2014-0012\FA finassur.doa 6 3/10/2014, Rev. 0