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. wells MWl , MW2 and MW-5 tested above the detection limits for the <br /> Volatile Aromatic Compounds of Benzene, Toluene, Ethylbenzene, and <br /> Xylenes (BTEX) , see Table 3 and Appendix B. <br /> On September 5, 1990, samples from monitor welds MW3, MW4, and MWF <br /> were obtained for analysis of fecal coliform. Monet,.3r wells MW3 <br /> and MW4 are below detection limits of 2 MPM/100ml, while monitor <br /> well MW6 tested at 11 MPN/10oml, see Appendix B. <br /> SOIL REMEDIATION <br /> As stated earlier the tank excavation was extended to the 25 foot <br /> depth and samples were taken at that time, June 26, 1990. All the <br /> samples were non detect, less than 10 ppm, for Total Petroleum <br /> Hydrocarbons (TPH) . Minor amounts of toluene, ethylbenaene, and <br /> xylenes showed up in the sample taken from the center of the <br /> excavation Ex-5 and miner amounts of xylenes showed up in the <br /> samples taken at the southeastern edge of the excavation Ex-A and <br /> EX-B. The soil analysis from the placement- of the two additional <br /> monitor wells (MW5 and MW6) were all below detection limits for <br /> TPH and BTEX with the exception of the sample obtained from MW5 at <br /> the true vertical depth of 33 feet, wh-ch had minor amounts of <br /> toluene and, xylenes. <br /> Excavation of the pump island area commenced on August 16, 1990. <br /> Using Manley and Sons backhoe and operator, three trenches were <br /> cut to the six foot depth through each of the three island areas, <br /> paralleling Harding Way. The excavated soil from these cuts were <br /> screened by a WEGE geologist for odor and with a HNu photoionizing <br /> detector (PTD) . The trenches were advanced until no odor or <br /> detectable readings were found in an east-west direction. Once <br /> the contaminated soil was delineated in these trenched areas, <br /> excavating was performed in a north and south direction to the <br /> thirteen foot depth. Samples obtained from the base of the middle <br /> island .area indicate that the excavation was successful in <br /> removing the contaminated soil from this area, see Table 1 <br /> (PL2(EXC2A & 2B) . To enable the backhoe to proceed deeper, ramps <br /> were constructed into the west and east pump island areas. The <br /> excavations of the western and eastern pump islands were then <br /> deepened to the twenty foot depth. Samples obtained frun the base <br /> of these two excavations show that contaminated soil still exists <br /> beneath the 20 foot depth, see Figure 3C and Table 1 (PL1(EX1-PB) <br /> and PL4(EX3-PA) ) . All samples were preserved, labeled, and chain <br /> of custody hand delivered to Chemtech Laboratories for analysis <br /> using EPA methods 8015 and 8020 with 5030 extraction. The <br /> excavated soil was covered with polyethylene liners, until <br /> laboratory results indicated the amount of soil, that could be <br /> aerated at the site. Previous classification of excavated soil <br /> for this site shows that this soil can be handled as non hazardous <br /> waste, see Table 4. <br /> SOIL SAMPLE RESULTS <br /> ---' Soil samples of the tank excavation and nearby monitor wells <br />