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detectable levels of TPH, and benzene concentrations of 0 0088 ppm, ND, and ND, respectively Soil samples from Borings CPT-2 and CPT-3 contained TPH concentrations of 3,500 and 10,000 ppm, respectively, and benzene concentrations of 55 and 160 ppm, respectively Ground water samples collected from all 14 CPT borings contained TPH concentrations ranging from ND to 240,000 parts per billion (ppb) The highest concentrations were detected in the vicinity of the former UST complex and to the north and northwest of the UST complex The chemical analytical findings for the CPT borings are summarized on Fugro's Table 2 and 3 contained to Appendix A Temporary piezometers were installed in three of the CPT borings These piezometers were surveyed, water level measurements were collected, and the ground water flow direction was calculated to be north/northeast On January 18 and 19, 1995 Wells MW-2 through MW-5 were drilled and installed at the locations shown on Plate 2 Soil samples collected from MW-2, MW-3, and MW-4 at 14 fbg did not contain detectable levels of TPH and BTEX TPH was ND in soil samples collected from MW-5 at 6 fbg Benzene was detected at a concentration of 0 0057 ppm TPH and BTEX were not detected in the soil sample from 11 fbg The soil sample collected from 14 fbg in MW-5 contained 43,000 ppm TPH and 940 ppm benzene Quarterly monitoring and samphng was initiated in these wells and has been ongoing since their installation Free product removal by hand bailing was performed in Wells MW-1, MW-5 and RW-1 which resulted in the removal of approximately 449 gallons of product The total amount of free product removed by hand bailing and vacuum truck extraction is estimated to be 1,271 gallons In May 1995 Wells MW-1 and RW-1 were properly destroyed prior to tank removal activities The four USTs were removed on May 2, 1995 An estimated 1,044 cubic yards of soil containing petroleum hydrocarbons were removed from the UST complex vicinity prior to backfilling the excavation Soil samples were collected from the former UST excavation at locations specified by an SJCPHS representative These sample locations are shown on Fugro's Figure 3 contained in Appendix A The chemical analytical results for these soil samples are listed on Fugro's Table 5, in Appendix A Ground water in the former UST basin rose to I 1 fbg Thus backfilling of the pit was completed using 2-inch rock from depths of 15 fbg to I 1 fbg A layer of filter fabric was placed on top of the rock and silty sand backfill material was used to fill the remaining excavation Two new 15,000 gallon USTs were installed May 11, 1995 in a new location at the site 666 yd' of soil were excavated from the new UST excavation and transported for disposal off-site In mid May, the former piping trenches were over-excavated and soil samples were collected as specified by an SJCPHS representative The soil chemical analytical finding for these soil samples are presented on Fugro's Table 5 in Appendix A An additional soil sample was collected by hand augering beneath the eastern canopy at the location where elevated levels of petroleum hydrocarbons were detected in one 240-0783 3