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.Draft Environmental Impact Report Page IV.F-5 Forward Inc. Landfill Expansion Surface Water Quality The RWQCB Order R5-2003-0049 requires quarterly surface water quality monitoring at two points on the former Austin Road Landfill site, when surface water is evident. One of the sampling locations, SW-1, is located upstream of the landfill and represents background conditions. The other sampling point, SW-2, is located immediately downstream of the landfill, and is designed to evaluate surface water quality impacts from the landfill. Monitoring at the Forward Landfill is conducted only when runoff escapes the surface water collection system, which diverts surface water to the evaporation pond on the facility. Beneficial uses of Littlejohns Creek designated, as specified in the San Joaquin River Basin Plan, are agricultural supply, industrial service and process water, contact and non-contact water, recreation,warm fresh water habitat, preservation of rare, threatened and endangered species, and.groundwater recharge. The perennial nature of Littlejohns Creek means that the surface water samples are analyzed every quarter for the Austin Road Landfill monitoring. Surface water sampling and analysis is not always performed at the Forward Landfill because, at times, there is no water to sample at those points. The field parameters sampled for quarterly are temperature, specific conductance, pH, and turbidity. In addition to the quarterly sampling,biannual(twice a year) sampling occurs for total dissolved solids, total suspended solids, chloride, sulfate, dissolved oxygen, and nitrate. During the second quarter 2008 sampling at Forward and Austin Landfill units (Geo-Logic, 2008b)the surface water samples collected showed no detectable VOCs were reported. A comparison of he upgradient and downgradient surface water samples showed similar inorganic constituent concentrations, suggesting the landfill units are not impacting surface water quality. NPDES Stormwater Monitoring Program Forward and Austin Road Landfills both have current National Pollution Discharge Elimination System (NPDES)monitoring programs and Storm Water Pollution Prevention Plans (SWPPP)in place. These programs, overseen by the RWQCB, include storm water inspection, sampling, observation, and reporting. Previous discharge was to receiving waters at Littlejohns Creek but that has been replaced by use of the treated groundwater to: 1) use for onsite dust suppression and other operations uses, or, 2) use for artificial recharge reinjection into the local aquifer. The 1 aquifer replenishment versus discharge to the surface water eliminates the clean treated water �J from the groundwater treatment system from being discharged into Littlejohns Creek. As the landfill expands, the facility will be required to update its NPDES and SWPPP. ] Groundwater f� Regional Groundwater Conditions Underlying San Joaquin County is a portion of the vast subsurface groundwater aquifer system of the Central Valley of California. Groundwater occurs in unconfined and confined conditions. The upper regional aquifer is typically an unconfined aquifer within the Victor Formation geologic unit. A minor perched water table at an elevation of about 20 feet amsl was encountered while drilling one of the site wells;perched water tables in the area are of a limited extent. The Victor Formation consists of over 100 feet of clay, silt, and fine to coarse sand and gravel. Sedimentary formations underlying the Victor Formation include additional, productive confined aquifers. Groundwater within one mile of the site is tapped by irrigation