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2-2 treatment system has been installed to mitigate detected chlorinated hydrocarbon in the first encountered groundwater beneath the northern portion of the FL. This system includes 13 groundwater monitoring wells. 2.2.2 Groundwater Control Four groundwater extraction wells with a combined design capacity of 305 gallons per minute (gpm)were installed to extract polluted groundwater at the northern portion of the FL. VOCs are stripped from the extracted water and the treated water is discharged to a recharge basin north of the North Branch of the South Fork of Little John's Creek, where it recharges the underlying aquifer. The groundwater treatment system and discharge are regulated by the RWQCB under WDRs. 2.3 Surface Water 2.3.1 Surface Water Protection The surface water control plan for the existing FL consists of an integrated system of bench ditches, perimeter channels, and storm water retention basins. The final landfill is designed so that surface water would run off via sheet flow until it is intercepted by a bench ditch. Bench ditches subsequently drain toward downdrains, which discharge to perimeter channels. Finally,the perimeter channels drain to the one of three sedimentation/detention basin. As required by the site's WDRs, permanent storm water runoff and drainage control facilities for the FL have been designed to convey peak discharge resulting from 1,000-year, 24-hour storm event runoff volumes. The only surface water bodies adjacent to the site are the North Branch and South Branch of the South Fork of Little John's Creek which are tributary to the San Joaquin River. The North Branch has been realigned to flow to the north and west of the FL and the South Branch flows along the southern border. 2.3.2 Surface Water Monitorinfs Surface water monitoring is completed quarterly in accordance with the site's WDRs. Monitoring is performed for the North Branch and South Branch of Little John's Creek and at the three sedimentation basins. 2.4 Storm Water Monitoring The RWQCB regulates municipal and industrial stormwater discharge requirements under the NPDES program. A Storm Water Pollution Prevention Plan (SWPPP) and a Monitoring Program and Reporting Requirements (MPRR) have been prepared for the FL in accordance with NPDES No. CA0082911. The SWPPP is updated annually, when necessary, to include various phases of construction when there is a change in construction, operation, or maintenance procedures, which may cause the discharge of significant quantities of pollutants to surface water, groundwater, or Forward Landfill Stage 113 Partial Final Closure/Post-Closure Maintenance Pian June 2011 SWT Engineering z:\projects\allied waste\forward\11-1014 partial fnl clsr pen\partial final closure plan document\text\sec 2.doc