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Following collection of the groundwater grab samples, each hydropunch boring will be sealed by pumping neat cement through the drive rods during withdrawal. Sealing of borings will be completed under inspection by a representative from the SJCEHD. Each boring location will be patched with asphalt or concrete to match surrounding pavement. GROUNDWATER MONITORING WELL DRILLING AND INSTALLATION Well borings MW-16 and MW-17 will be drilled at the approximate locations shown on Figure 3 Each soil boring will be hand augered to a depth of approximately 5 feet bgs to identify any unmarked subsurface utilities or obstructions. The soil borings will be extended to their final depths with a truck-mounted drill rig equipped with 8-inch outside diameter, continuous-flight, hollow-stem augers. It is proposed that the hollow-stem augers will be fitted with a wooden plug and straight drilled to their final depths to avoid flowing sands from entering the augers and obstructing installation of the wells to their target depths of 105 feet bgs (MW-16) and 80 feet bgs (MW-17). Soil wastes generated during drilling will be temporarily stored on-Site in a roll- off bin pending profiling and manifesting for disposal at a Class III landfill. Groundwater monitoring wells MW-16 and MW-17 will be installed in their respective borings using 2-inch diameter Schedule 80 PVC casing with 10 feet of 0.010-inch slotted screen placed at the base of the well bore. A #2/12 screen-washed sand will be placed in the annulus to approximately 2 to 3 feet above the screened interval. An additional 2 feet of time-release coated bentonite pellets will be placed above screen-washed sand and allowed to hydrate for approximately 30 minutes. The remainder of the well annulus will be sealed with neat cement to within 12-inches of the ground surface. Each well will be secured in an 8-inch diameter traffic- rated steel vault encased in concrete. Well sealing and grout placement will be completed under inspection by a representative from the SJCEHD. FREY field staff will maintain a log of each boring during drilling to document soil lithologies and well construction details. GROUNDWATER WELL DEVELOPMENT AND SURVEYING Newly-installed groundwater monitoring wells will be developed by surging and bailing, and by pumping with an electrical submersible pump. Well development will be completed no sooner than 72 hours after installation. In conjunction with well development activities, a state-licensed land surveyor will be scheduled to survey the newly installed wells for vertical elevation and horizontal location in accordance with State of California GeoTracker standards. SEMI-ANNUAL GROUNDWATER MONITORING AND SAMPLING Approximately one week after installation and development of the newly installed groundwater monitoring wells, and select existing groundwater monitoring wells will be gauged and sampled, as outlined in the proposed monitoring and sampling schedule presented in Appendix D. Monitoring and sampling will be completed in accordance with the field procedures described in Appendix C. FREY Environmental,Inc. 9 Project No. 1095-01