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Currently,groundwater at the site is monitored by network of six monitoring wells: Wells MW-4, MW-5, MW-8, and SB-1 monitor a shallow aquifer. Wells MW-6 and MW- 7 monitor a deeper aquifer. 3.0 EVALUATION MONITORING PROGRAM FIELD WORK In August 2011,the County submitted an EMP Workplan to further characterize the nature and extent of VOCs migrating from the CHSL in accordance with the Order. The workplan outlined a program for temporary and permanent well construction,well development, sampling, analysis, and data evaluation. This Workplan was approved by RWQCB staff in late August 2011. A revision to this EMP workplan allowing the use of HydropunchTM sampling methods for temporary well construction was submitted and approved by RWQCB staff in September 2011. A first phase of drilling and well construction was conducted in October 2011, and resulted in construction of temporary wells MW-9, MW-10, and MW-11 that were subsequently abandoned with the approval of RWQCB staff after preliminary groundwater sampling results indicated the presence of elevated VOCs. Following the EMP workplan, "step out" wells MW-9A, MW-10A, and MW-11A were constructed at locations where VOC concentrations were expected to be closer to or below their respective Method Detection Limits (MDLs). 3.1 Well Construction Three permanent wells (MW-9A, MW-10A, and MW-11A)were drilled and constructed within the easement north and south of Interstate Highway 580 at the locations shown on Figure 1. Drilling, logging, and construction practices were performed as approved in the EMP Workplan and in accordance with procedures summarized in Department of Water Resources Bulletin 74-90 (California Well Standards) and the regulations outlined in the permit for well construction granted by the San Joaquin Department of Environmental Health. All work was performed under the direct supervision and was documented by a California State Certified Engineering Geologist. Borehole drilling and well installation services were provided by Gregg Drilling(California State Contractor's License No. C57-485165). 3.1.1 Well Permitting-Drilling and well construction permits were obtained through the San Joaquin County Environmental Health Department. Copies of the permits will be included in the final EMP report that will be provided to the RWQCB at the conclusion of the project. Caltrans granted an encroachment permit to drill and install the new wells in their right of way. Easement to these locations has been granted by Caltrans allowing the County access for monitoring. Well Completion ReportPage ■ 2 Corral Hollow Sanitary Landfill ASSOCIATES May 3,2012