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excavation,CPT#2 is directly east of the UST excavation,and CPT#3 is in the sidewalk on the north side of Lafayette street. (see drawing attached). These three CPTs would be sampled at various intervals to determine if contamination is present. CPTs will be driven to a depth of 80 feet bsg. or as necessary to determine the extent of contamination. Proposed CPT#3 is located in the sidewalk on the north side of Lafayette Street,and permits for this work must be obtained from the City of Stockton and Caltrans. Replacing existing Monitoring Wells Due to recent history of the groundwater at+/-30 feet bsg.,the existing monitoring wells should be replaced with wells that represent and can sample the surface of the groundwater. Replacement monitoring wells will be constructed as shown on the attached drawing. Soil Sampling with CPT Soil samples will be logged and classified by the Unified Soil Classification System.All soil samples will be sealed and placed under ice.Samples will be transported under Chain of Custody to Sherwood Labs for analysis. Spoil from the monitoring well construction will be placed in drums for disposal. 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 well be analyzed by EPA methods 8020 (BETX), 5030/8015(M) (TPH Gasoline)and 8260(oxygenates). Water samples well 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 and continue until terminated by PHS/EHD. HYDROLOGY SURVEY WORK PLAN The requested hydrology survey of existing wells will be conducted for a radius of 2000 feet from the site. All recorded wells or surface water will be shown on a City of Stockton map with notes for type and construction. Discharge and recharge rates from known sources will also be noted. Trace element analysis or conductivity grid analysis is not a part of this work plan. The evaluation of the effects of pump discharge on the hydraulic gradient in the area of the site is very costly and is not being proposed at this time due to the limited funds allotted for this site from the State Underground Cleanup Fund. It is proposed that water samples be taken and analyzed from any producing well within 1000 feet down gradient from the site. Page 2 of 3