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was the installation of three CPTs. To date CPT41 and CPT#2 have been installed, and findings reported to the PHS/EHD. Soil and groundwater samples extracted during the installation of CPTs indicate gasoline contamination to a depth of eighty-five feet(recap attached). CPT#3 has been delayed, due to the lack of an encroachment permit from Caltrans. The encroachment permit was applied for on November 11, 1999. All replacement monitoring wells have been sampled quarterly, and a recap of the findings is attached. WORK PLAN FOR INSTALLATION OF THREE DEEP MONITORING WELLS Well Placement The plan revolves around the development of a ring of monitoring wells that are as close as possible to a 100' radius from the center of the UST excavation. The down slope direction of the hydraulic gradient is to the Northeast in the direction of the Crosstown Freeway. CPT#3 will serve as the northern most evaluation point. Proposed monitoring wells MW#4 and MW#5 will serve as evaluation points for the southeast and east directions. Soil Bore Sampling The soil boring for MW#4 and MW#5 will be sampled on five foot intervals with a standard BX split spoon soil sampler. Sample tubes will be capped with teflon sheets and sealed with a plastic cap and duct tap. Each sample will be place on ice for transported to a certified laboratory under chain of custody. Soil sampling from the soil bore for MW#6 is not proposed due the close location to CPT41. Soil sample analyses for CPT#1 are recorded on the attached recap sheet. Monitoring Well Construction Monitoring wells will be constructed of two inch PVC casing in an eight-inch soil bore. The bottom ten feet of the well casing will be slotted (see an attached sketch). Monitoring Well Sampling All new monitoring wells will be developed and purged. After purging, each well will be sampled for analysis. The static groundwater elevation will be determined before purging. The water table elevation will be established from City of Stockton Datum. Sample Analysis Soil samples will be analyzed by EPA methods 8020 (BETX), 5030/8015(M) (TPH Gasoline)and 8260(oxygenates). Water samples will be analyzed by EPA methods 602 (BETX), 5030/8015(M) (TPH Gasoline) and 8260(oxygenates). Report of Findings A report of the findings of each soil and water sample analysis will be issued with recommendation for any future action that may be required. Future Quarterly Monitoring Well Sampling After all new monitoring well construction is complete,quarterly monitoring of all wells will begin Page 2 of 3