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Project 113-13 July 9, 190 Page 2 A fourth monitoring well was installed by Parker Environmental Services at the site on September 6, 1991. Soil samples analyzed from the boring were all non-detect for TPH-g and BTEX. Groundwater samples obtained on September 11, 1991 from all four monitoring wells were also non-detect for TPH-g and BTEX Depth to groundwater was 28 to 29 feet below ground surface. An aquifer pump test was done by Parker Environmental Services at the site October 15-16, 1991, and it showed that all four monitoring wells are in the same aquifer. At this time no cleanup efforts have been implemented. Decisions concerning future investigations or remediation will be discussed after four quarterly monitoring reports are completed. IL Current Activities Groundwater samples were obtained on July 1, 1993. Prior to sampling, groundwater elevation measurements were obtained. Results are presented in the table below. Table 1 Cheaper Store #76 890 North Main Street, Manteca, California Groundwater Measurement Results* Measured on July 1, 1993 MW-1 MW-2 MW-3 MW-4 Well Elevation 33.12 3322 3355 3366 Depth to GW -27.48 27.24 27.69 -2808 GW Elevation 564 5.98 5.86 5.58 * elevation above mean sea level, in feet Shallow groundwater measurements indicate the water table is approximately three feet lower than measurements taken in March, 1993. As shown on the attached groundwater flow direction drawing, the flow direction is toward the southeast, unchanged from the March, 1993, measurements. Each monitoring well was purged using an electric submersible pump prior to sampling Approximately 5 gallons was removed from each well, which equaled at least three well volumes per well. All purge water was placed in a sealed metal 55 gallon drum (DOT 17H). After each well was purged, a sample was taken using a disposable PVC bailer. The water from each well was placed in two 40 milliliter vials filled so that there was no air (head space) remaining in them. Samples were labeled and placed on ice in a cooler for transport to a state certified hazardous materials testing laboratory, McCampbell Analytical of Pacheco, California. Before the next well was purged and sampled, the pump was run in one bucket with non-phosphate detergent and two separate buckets with tap water. All purge water and equipment wash water was placed in 55 gallon steel drums and remains on-site. When the Parker Environmental Services 190 East 7th Street Pittsburg CA 94565-6116 Phone (510) 439-1024 Fax (510) 439-2566