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i Wastewater generated from the steam cleaning of the augers and evacuation of groundwater from the soil boring during grouting were stored in labeled 55 gallon DOT approved drums inside the fenced compound This wastewater, along with water generated from the purging of monitor wells during quarterly groundwater sampling, was transported by Evergreen Environmental Services to their recycling facility under a non-hazardous waste manifest(Appendix C) RESULTS OF SOIL AND GROUNDWATER INVESTIGATION The certified analytical laboratory results from the four soil samples and two groundwater samples collected on March 26, 1998 are listed in Table 1 A copy of NSE's laboratory report is included as Appendix D of this report SOIL TPH-G concentrations in the four soil samples ranged from a maximum of 770 mg/kg in the shallowest sample collected from 25 5 feet bgs to below the laboratory detection limits of 0 5 mg/kg in the sample from 36 0 feet bgs The soil samples from 30 5 and 40 5 feet bgs showed TPH-G concentrations of 4 0 mg/kg and 2 0 mg/kg respectively Benzene concentrations in the four soil samples ranged from a maximum of 1 7 mg/kg in the sample collected from 25 5 feet to below the laboratory detection limits of 0 005 in the sample from 36 0 feet The soil samples from 30 5 and 40 5 feet bgs showed Benzene concentrations of 0 009 mg/kg and 0 02 mg/kg respectively The soil sample collected from 25 5 feet bgs showed the highest TPH-G concentration and was analyzed for concentrations of the oxygenants MTBE, TBA, ETRE, DIPS, and TAME All analytes were below the laboratory detection limits of 0 005 mg/kg GROUNDWATER TPH-G concentrations from the two groundwater samples collected by the hydropunch method at 33-35 feet bgs and 43-45 feet bgs were 0 17 mg/1 and 19 mg/1 respectively Benzene concentrations in the two groundwater samples collected at 33-35 feet bgs and 43-45 feet bgs were 0 007 mg/l and 0 011 mg/I respectively MTBE concentrations in the two groundwater samples were 0 22 mg/l at 33-35 feet bgs and less than the laboratory detection limits of 0 001 mg/1 at 43-45 feet bgs The remaining four oxygenants (TBA, ETBE, DIPS, and TAME) were not found above the laboratory detection limits in either of the groundwater samples DISCUSSION OF RESULTS The certified analytical laboratory results from the four soil samples collected from THl (representing the likeliest location for contaminants at depth) show that significant soil contamination extends to a depth of 25 5 feet bgs surface but quickly diminishes to less than 5 ppm TPH-G between 25 5 and 30 5 feet bgs and remains below 5 ppm TPH-G from 30 5 to 40 feet bgs The soil contaminants included BTEX constituents, but the oxygenants TBA, MTBE, ETBE, DIPS, and TAME were not present These results are consistent with the previous laboratory . results from the nearby strata probe test hole SP-E that showed significant TPH-G contamination at 16 feet bgs (14, 000 mg/kg) and 21 feet bgs (2000 mg/kg) but less than laboratory detection limits 4 SANCHEZ SRPT 5/11/98