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Former Discovery Chevrolet December 7, 1994 .J Development water was stored in properly labeled 55 gallon Department of Transportation (DOT) approved drums pending proper disposal. Well development field data sheets are presented in Appendix C. Well Monitoring and Sampling The monitoring wells were sampled by G-R on September 16, 1994. G-R well sampling. procedures. are presented_ in Appendix A. Mr. Michael Collins of SJCEHD was onsite to witness the sampling procedures. Monitoring data was recorded and the groundwater samples were transported to the laboratory for the requested analyses. Monitoring data is summarized on Table 2. Well sampling data sheets are presented in Appendix C. Wellhead Survey Following completion of the wells, the . well elevations and locations were surveyed by Virgil Chavez Land Surveying of Vallejo, California (license #PLS- 6323). Top of casing .and vault box elevations were measured relative to MSL. Virgil Chavez surveyed the top of casing point that had been marked during the previous sampling activities. A copy of the Surveyor's report is included in Appendix D. RESULTS Soil and Groundwater Conditions Based on subsurface work performed to date at the subject site, soil underlying the site is predominantly clay and silt to approximately 10 to 15 feet bgs. At approximately the soil/water interface a decrease in the clay content and an increase in the sand and silt begin with increasing sand to the total depth investigated (20 feet bgs). Soil from the surface to approximately 8 feet bgs in MW-1 contains gravel that appeared to be backfill indicating this boring location was partially in the former gasoline UST cavity. Groundwater ,was encountered in each boring from 10 to 10.5 feet bgs. Boring MW-1 and MW-2 exhibited field evidence of hydrocarbon impact from the soil surface to groundwater. A noticeable hydrocarbon odor and discoloration was present in the soil samples and drill cuttings from these borings. 'Readings taken in the field with the PID showed relatively high concentrations (714 to'1585 ppm) of hydrocarbons from these borings. Boring MW-3 showed no field , Report No, 8146701.1 4 GeoStrategies Inc.