SITE INFORMATION AND CORRESPONDENCE

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AM Ms. Mary Meays A� RL: Marital Deduction Trust June 12, 1992 Page 2 i photoionization detector (PID) for volatile organic content. The second liner was sealed at each end with a Teflon sheet and plastic cap, secured with duct tape, sealed in an air-tight bag, and preserved on ice pending shipment to a state-certified laboratory. Between sampling attempts, all sampling equipment was cleaned using the three-bucket wash system. In this system, the liners and samplers are scrubbed with a brush in a bucket of tap water and detergent, rinsed in a second bucket of tap water, and given a final rinse in a bucket of distilled water. I Laboratory Analyses The sample collected at the soil/groundwater interface, . sample MW4-19, was chosen for laboratory analysis. This soil sample was sent o state- certified RESNA Environmental j Laboratories in Fremont, California. The sample was analyzed for benzene, toluene, ethylbenzene and xylenes (BTEX) using EPA meth 8020 and total petroleum hydrocarbons as diesel (TPHD) using modified EPA method 8015. Laboratory analyses determined that BTEX and TPHD concentrations were below method detection limits for all analytes of concern. Laboratory reports with chain-of-custody documentation are included in Attachment 1. Groundwater Monitoring and Sampling On March 5, 1992, RESNA Industries personnel monitored groundwater depths and collected groundwater samples from wells MW 1, MW2, and MW3. Following well development on March 24, 1992, all wells were monitored and a grot ndwater sample was collected from MW4 (Attachment 2). Water level measurements were co lected from each monitoring well using a Solinst Water Level Meter (Model 101). Groundwa er monitoring was conducted on May 21, 1992 to confirm the groundwater gradient direction. Water levels have decreased an average of 1.72 feet since March 1992 (Table 1). A groundwater gradient map was created using data from the May 21, 1992 monitoring event which includes the recently installed well MW4 (Figure 2). The gradient is approximately 0.015 feet/feet or 79 feet/mile in a east-southeast direction. Prior to sampling, 3 to-5 well volumes of water were urged from each well. The samples were collected using a dedicated, disposable bailer, The samples were submitted to RESNA Environmental Laboratories in Fremont, California. 11 samples were analyzed for BTEX using EPA method 8020/602 and for TPHG using modiffid EPA method 8015. Additional analysis for TPHD was performed on monitoring wells 1 and MW4. Fecal coliform analysis of MW4, as requested by the San Joaquin County PHS EHD, was conducted by A & L Western Agricultural Laboratories in Modesto, California. Analysis was not requested for monitoring L051592.GLN