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in- previous ate investigations conducted at the Site. Laboratory analytical results- indicated that the selected soil samples that were analyzed from the well construction activtties contained non- detectable concentrations of TPHd, total petroleum hydrocarbons as oil and grease (TOG) , po2ychlorinat-ed biphenyls (PCH) , volatile organic compounds (VOCs) , and semi-VOCs (SVOCs) whish were below the California Regional Water Quality ,Control Board' s environmental Screening Levels 4ESL5, where groundwater is a current or potential source of drinking water) for commercial/lndustrIal landuse. Cadmium, chromium, hexachrome, lead, nickel and zinc detected in the soil samples Were within background levels for soil in the California Central Valley and below their - resjective carmerciallindustrial ESLs. The groundwater samples contained non- detectable concentrations of TPHd, TOG, ?CBS, VOCs, and SVOCs. The metal concentrations contained in the groundwater samples were generally below their respective detection limits and EM, with the exception of the groundwater sample collected from well MW-1. The nickel contained in well MW-1 was above the ESL of 8 . 2 ug/L. ICES collected six rounds of groundwater samples from wells MW-1, MW-2, and KW--3 in May, June, Septewher, and December ' 2006: June 2047; and February 2008. laboratory analytical -results of the six groundwater sampling events indicated that the residual TPHd, TOG, ?CBs, VQCs, Svocs, and metal concentrations to wells MW-1, MW-2, and MW-3 were generally below their respe.ctivq ESLs . 4.0 SUPPLEMENTARY SOIL .AND BOIL VAPOR INvESTIGATxON A trilling permit will be obtained from the San Joaquin County Environmental. Health Department (SJC-ESD) prior to site investigation activities. Site preparation will include screening the proposed boring locations using a magnetometer to assess the potential presence -of underground utilities. underground Services Alert and Cruz Brothers of Scotts valley, California will be contacted Co assist in utility locating activities prior to initiation of investigation activities. So l -samples will be collected from four onsite bocingt (B-1 through B-4) looted within a distance of approximately 10 to 15 feet from the former UST pit . The appcoximate. boxing locations ere shown in Figure 2 . Soil vapor samples will be collected from four onsite boxings (SV-1 through SV--4) located adjacent to borings B71 through B-4. 3