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representative will also be required to approve the proposed locations and to accurately mark any private utilities on site. Health and Safety A site-specific hazard assessment was performed during a reconnaissance of the site. Based on this hazard assessment, a site specific HASP will be prepared to mitigate or reduce both physical and chemical hazards. Well Permitting ATC will secure well installation permits with the SJCEHD prior to commencing the investigation. A well installation permit application is attached to this workplan. Well Installation An ATC geologist will mark the locations of the proposed wells, and contact Underground Service Alert (USA) who will provide clearance so that no public underground utilities will be disturbed. The site owner or representative will also be required to approve the proposed locations and to accurately mark any private utilities on site. ATC will install three groundwater monitoring wells. The groundwater monitoring wells will be drilled using a truck-mounted Mobile B-61 drill rig, or equivalent, equipped with continuous flight, hollow stem augers. The groundwater monitoring wells will be drilled to a maximum depth of approximately 38 feet below ground surface(bgs). Undisturbed soil samples will be collected at approximately 5-foot intervals from each soil boring. Soil samples will be obtained with a California modified split spoon sampler. The sampler will be driven into undisturbed soil ahead of the auger bit using a 140-pound downhole hammer. The split spoon sampler holds three brass tubes for the collection of soil samples. Soil samples will not be obtained for laboratory analysis. The soil in the uppermost tube will be examined for lithology (provided complete sample recovery occurs). The field geologist, under the direct supervision of a California Registered Geologist, will prepare a log of the subsurface conditions. Soil samples will be classified in accordance with the Unified Soil Classification System (USCS). The groundwater monitoring wells will be completed first using 2-inch diameter, Schedule-40, polyvinyl chloride (PVC) casing. The wells will then be set with 20-foot sections of 0.010-inch slotted screened PVC casing set at the bottom of the well. The tops of the screened casing will be at least 5 feet above the groundwater first encountered in the boreholes. Number 2112 Monterey sand will be used as filter pack surrounding the well screen, as appropriate. The wells will be surged after the placement of the sand pack in order to set the sand pack, subsequently 3-foot bentonite seals (hydrated bentonite chips)will be added on top of the sand. Concrete-bentonite grout will be added on top of the bentonite seal to approximately 1-foot bgs. The wells will be secured at the surface with a flush- mounted traffic rated well box. ATC Associates Inc. 3 75.75128.0001