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udµM[q$ .,ESGNENS COgSixTANiS The monitor well was developed by bailing 13 gallons of groundwater from the well (approximately 5 well volumes) The top-of-casing elevation of MW-5 was surveyed at 54 24 feet above sea level by Nolte and Associates of Manteca 2.1.3 Analy1ical Methods Soil samples were analyzed by EPA Method 8020 for benzene, toluene, ethylbenzene and total xylenes (BTEX) and by EPA Method 8015M for total petroleum hydrocarbons-gasoline fraction (TPH-G) The analyses were performed by American Environmental Network of Pleasant Hill, California f2.1.4 Decontamination Procedures All sampling equipment, including stainless steel sleeves, and split spoons, were decontaminated prior to use with a tnsodium phosphate solution followed by a potable water nnse The drill rig and hollow stem augers were steam cleaned prior to drilling 2.1.5 Waste Handlin Soil waste and decontamination fluids generated dunng the investigation were stored in 55-gallon drums at the facility 2.2 RESULTS 2.2.1 H dra eolo ical Data Saturated soil was first encountered at 55 ft bgs during the drilling of MW-5, however, the static water level was 53 5 ft bgs following the installation of the monitor well The unsaturated zone (less than 53 5 ft bgs) is composed of sand, silty sand, and silt The saturated zone is composed ' of silty sand and poorly graded sand with silt 2.2.2 Soil Analytical Results Table 2-1 presents the soil analytical results for MW-5 Analytical reports are presented in Appendix C. Six soil samples were submitted for analysis Five of the samples were collected above the static water level At 25 ft bgs toluene (5 0 mg/Kg), ethylbenzene (36 0 mg/Kg), xylenes (290 0 mg/Kg), and TPH-G (2,100 mg/Kg) were detected At 30 ft bgs toluene (6 0 L TROJ£Cr"ANJOQWCLODI RFP 4 JBOmry IW7