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f k t A on September 5, 1990, samples from monitor wells MW3, MW4, and.MW6 were obtained for analysis of fecal coliform. monitor wells MW3 and MW4 are below detection limits cf. 1 MPY/100ml, while monitor well MW6 tested at 11 HPN/100m1, this analysis was not run during this most recent sample nnaasais. SOIL RENEDIATION As stated earlier the tank excavation Bras extended to the 25 foot depth and samples were taken at that time , :,lune 26, :1990. All the samples were "non detect", less than 10 ppm, for Total Petroleum Hydrocarbons (TPH) . Minor amounts of toluene, ethylbenzene„ and :xylenes showed up in the sample taken from the center of the excavation EX-5 and minor amounts of xylenes showed up in. the samples taken at the southeastern edge: of the excavation EX-R and EX-B. The vapor extraction well Ell was drilled and sampled on October 9, 3990, and showed 2 ppm gasoline range hydrocarbans at the 30 and 37 foot depth with the BTEXfs being below detection limits for these samples. The soil analysis from the placement of the two additional monitor wells (MWS and MW61 were all below detection limits for TPH and BTEX with the exception of the sample obtained from MWS at the true vertical depth of 33 feet, which had minor amounts of toluene and xylenes,. see Table 1 and Appendix B. Excavation of the pump island area commenced on August 16; 1990. Using Manley and Sons backhoe and operator, three trenches were Cut to the six fart depth through each of the three island areas, paralleling Harding Way. The excavated soil from these cuts were screened by a WEGE geologist for odor and with a HNU photoianizing detector (PID) . The trenches were advanced until no odor or detectable readings were found in ern east-west direction. Once the contaminated soil was delineated in these trenched areas, excavating was performed in a north and south direction to the thirteen foot depth. Samples obtained from the base of the middle island area indicate that the excavation was successful in removing the contaminated soil from this area, see Table 1 (PL2(EXC2A & 2B) . To enable the backhoe to proceed deeper, ramps were constructed into the west and east pump island areas. The excavations of the western and eastern pump islands were then deepened to the twenty foot depth. Samples obtained from.the base of these two excavations show that. contaminated..soil still:. :,exists boneath the 20 foot depth, see Figure 3C `and Table 1' (PL1(EX1-PB) and PL4(EX3-PA)) . On October B, 1990 vapor extraction wells P1 and P3 were sampled and installed at the eastern and western pump — -- — ----- island---excavations--respectively---Soil-sample--results—obtained___._-___— from the 30 and 40 foot .depth of P1 show 2 ppm gasoline range hydrocarbons with minor amounts of BTEX's. Soil sample results from. P3 show 12 ppm gasoline range hydrocarbons at the -25 foot depth and 2 ppm gasoline range hydrocarbons at the 30 and 40 foot pace 4