Laserfiche WebLink
4.5 Ground-water Sampling <br /> " Immediately follcwi,ng well development, groundwater samples were <br /> collected from each new monitoring well. Groundwater samples were <br /> collected from the additional monitoring wells on site after 3 to 5 <br /> mel' volumes of dater was purged from each well. Purged water was <br /> containerized in DOT approved drums and left an site pending <br /> laboratory analyses. <br /> 5soil <br /> Laboratory Analyses �- Soil and Groundwater <br /> and groundwater samples were sent to state-certified Applied <br /> r Analytical Environmental Laboratories ir,: Freemont, California. <br /> Selected soil samples were laboratory analyzed for BTEA using EPA <br /> method 8020 and TPE as gasoline using modified EPA method 8015. <br /> Laboratory analyses determined that benzene above method detection <br /> limits was detected only in soil samples from borings VPI and VP3 in <br /> concentrations which ranged from 0.008 ppm to 0.076 ppm. Total <br /> petroleum hydrocarbons as gasoline concentrations were detected only <br /> in borings ASB1 and VPI in concentrations which ranged from 2.4 ppm <br /> to 3300 ppm. Table 1 summarizes laboratory results. Laboratory <br /> reports with chain-of-custody documents are presented in Appendix <br /> t` III. Based on the laboratory analyses of soil samples by both <br /> Leedshill - Herkenhoff and RESNA, the lateral extent of hydrocarbon <br /> impacted soils is restricted to the former storage tank excavation <br /> and beneath the eastern dispenser island '(Figure 8) . This figure <br /> represents the lateral extent of hydrocarbon impaction at the site. <br /> '-- The vertical extent of hydrocarbon impaction is constrained b; the <br /> shallow water table at approximately 30 feet below grade. <br /> I . <br /> { <br /> - --- ----- ---- --- <br /> ' Wober point Ycoporty 475 <br /> 6 <br /> - ` <br /> RAP0591-TLP < <br />