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� AMBRIA <br /> rng1f� rn�11�g <br /> Maximum concentrations of 22 ppm TPHd and 86 ppm TRPH were detected beneath the former <br /> hoists No BTEX was detected in the samples collected TPHd was detected at a concentration <br /> of 2 7 ppm beneath the former waste oil tank, no other analytes were detected in the samples <br /> collected <br /> Cumulative soil sampling results are summarized in Table 1, and TPHg, TPHd, benzene, and <br /> MTBE concentrations are shown on Figures 3 through 6 <br /> i <br /> Hydrocarbon Distribution to Groundwater- During the second quarter 2005, no TPHg,BTEX, <br /> or MTBE were detected in any of the wells sampled at the site No TPHg or BTEX has been <br /> detected to site wells since at least `g �t .3 MTBE concentrations have been less than 5 <br /> jan- , 1-x"0 V <br /> ppb in site wells since at least Qctal�er-2003 Histoncal groundwater data and the third quarter <br /> 2005 groundwater contour map are included m Appendix A <br /> SITE-SPECIFIC INFORMATION REQUEST <br /> SJCEHD requested information regarding several items to facilitate closure consideration Each i <br /> . requested item and our response is presented below <br /> Crass-sections showing correlated soil lithologies, contaminant concentrations, lateral and <br /> vertical extents of impacted soil and groundwater, and contaminant migration path ways <br /> Cross-sectional diagrams were prepared in 1998 and are included as Appendix C As shown on <br /> the cross-section, soil types beneath the site are pnmanly fine-graded with beds of non-laterally <br /> continuous course-grained sediments occurring below 20 fbg <br /> As noted above, TPHg, benzene, and/or MTBE concentrations have only been detected in soils <br /> remaining at the site in the vicinity of the former northwestern USTs, the former hoists, and the <br /> former waste oil tank All other soil samples collected at the site have either been non-detect or <br /> the area was over-excavated to non-detect concentrations in soil Based on this, the extent of <br /> contaminants remaining in soil is defined both vertically and laterally and limited in area <br /> Furthermore, TPHg, BTEX, and MTBE concentrations have been low to non-detect in all site <br /> wells since at least 2003 Based on this, updated cross-sections with contaminant concentrations <br /> are not necessary for the site and were not prepared <br /> 0323 <br />