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. borings had been completed and sampled, they were destroyed by tremae placement of neat cement to surface MONITOR WELL DESTRUCTIONS Four groundwater monitoring wells were used to obtain groundwater samples for evaluation of the groundwater beneath the site MW1, MW2 and MW3 (screened intervals were between 30 and 50 feet below the surface) evaluated the first water bearing zone, were installed by William J Hunter and Associates in June 1995 MW4 (screened interval between 70 and 80 feet below the surface) evaluated the deeper water bearing zone, was installed by Western Geo-Engineers in June 2001 With the increasing groundwater elevation trend in Stockton the three 50 foot wells top of screen (30 feet below the surface) have been overtopped during seasonal recharge of the aquifer This drowning of the well screens has compromised the ability of the wells to produce representative water sample The current owner of the property has plans to build a building in the vicinity of the four previously installed groundwater monitoring wells All four groundwater monitoring wells associated with the site were destroyed by drilling out the well materials one foot past total depth and tremze grouting with neat cement with 5% bentonite to surface Well destructions were permitted by San Joaquin County Health, see Appendix B RESULTS . SOIL SAMPLES Forty three soil samples were submitted for laboratory analysis, based on field screen of the cores obtained from the drilling activities Table 1 contains all soil sample results generated from this site Figures were developed for Benzene in soil, due to the more toxic effects of Benzene when compared to other petroleum gasoline constituents Along with consideration to the future use of the property, building/shop built over the former UST area and the effects of Benzene on indoor air Figure 4 shows the current and historic benzene concentrations in soils between the 7 and 10 foot depth Benzene contaminated soil is isolated at the former UST excavated areas at Arc Pump and Fernando's Place Figure 5 shows the current and historic benzene concentrations in soil between 10 and 15 foot depth Again benzene contaminated soils are located at the former UST excavation areas at Are Pump and Fernando's Place Figure 6 shows the current and historic benzene concentrations in soil between 25 and 35 foot depth The benzene contaminated soils located at Arc Pump and Fernando's Place show spreading, which is most likely the result of the first water bearing zone migration of contaminants 7 ARC Pump, ASSESSMENT 2006