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REMEDIAL ACTION WORK PLAN, 1645 CHEROKEE ROMA STOCKTON, CA all hydrocarbon impacted groundwater encountered will be pumped from the excavation and contained in an above-ground holding tank pending profiling and subsequent transportation and disposal at an appropriate state certified disposal facility. 2.6 Soil Disposal All impacted soil removed from the site will be transported under non hazardous waste manifests to the Forward Disposal Facility located in Manteca,California for appropriate disposal. 2.7 Restoration The excavated areas of the site will be backfilled with selected overburden soils and approved clean imported materials. The overburden soils and imported aggregate materials will be placed in one-foot - lifts and compacted to 95%. Compaction will be verified and confirmed using a nuclear gauge by a state certified materials testing or geotechnical engineer. Upon completion of backfill activities, all disturbed surfaces will be restored with materials to match the existing surroundings. 3.0 GROUNDWATER MONITORING WELL INSTALLATION 3.1 Installation of Groundwater Monitoring Wells In accordance with the directives received from the SJCDEH to reconstruct the on site groundwater monitoring wells, BES proposes to re-install three new wells post remedial activities. As groundwater has been routinely encountered at the subject property at approximate depths between 45 feet and 48 feet bgs., each well will be installed to an approximate depth of 60 feet bgs. Each well will constructed of clean Schedule 40, 2-inch diameter, threaded poly vinyl chloride (PVC) casing. Screened casing with factory milled .010-inch slots will be installed in the center of the borehole from approximately60 to 40 feet bgs. Blank casing will be installed from approximately 40 to .5 feet bgs. A threaded cap will be placed at the top of the well screen prior to installation. A sand filter ,pack consisting of #212 Monterey sand will be placed in the well annulus from approximately 55 to 8 feet bgs. Prior to the annular seal placement, a surge block will be repeatedly pushed through the water in the well to ensure that no bridging of the filter pack material within the well annulus will occur. A 7-foot thick annular seal consisting of neat Portland cement and bentonite will be placed above the filter pack and the remaining annular space then filled with concrete. A traffic rated EMCO-Wheaton well box fitted with a removable lid will be placed within a concrete encasement so that the top of the lid will be raised slightly above grade. An expandable test well plug and lock will be used to secure the top of the well casing. A well construction schematic is presented as Figure 8. Proposed well locations are presented as Figure 9. 3.1.1 Groundwater Monitoring Well Development and Sampling Following well installation activities, the elevations of each well will be surveyed relative to a specified benchmark to the nearest 0.0 L foot and documented for future reference. Each well wil l be purged and developed no less than 24 hours after completing the grout seal. Fluid levels in each well �- will be measured to obtain data pertaining to the depth to groundwater and potential presence of free product. Upon completion of well development activities, groundwater samples will be collected from each well, packaged in appropriate glass containers, placed in a pre-cooled container, and submitted to a state certified laboratory for chemical evaluation. Each sample submitted will be subjected to chemical analysis of TPN-d using EPA method 8015. TPH-g, BTEX, fuel oxygenates, and related volatile compounds will be tested using EPA method 8260B. Additionally, each water 4 Bohn Environmental Solutions