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1 a 2.0 PURPOSE i The purpose of this report is to present analytical data collected during the June 22, 1995 quarterly sampling event. Sample collection methodology, laboratory analytical methods, analytical data and an evaluation of the.data.are described in subsequent sections of this report. F 3.0 SCOPE OF WORK The following tasks were conducted in order to meet the objectives of this phase of the investigation at this site: �I • Collect ground water elevation data accurate to 0.01 feet. { • Purge and sample six ground water monitoring wells to obtain representative samples. • Submit all groundwater samples to a California State certified analytical laboratory for analysis of petroleum hydrocarbon constituents and selected dissolved metals. • Prepare this report summarizing the methodology and analytical data obtained and making recommendations for further work as warranted. 4.0 METHODOLOGY On June 22, 1995, the six monitoring wells were purged and sampled. Prior to purging, each well was measured for depth to water and total depth accurate to within 0.01 feet. Each well was then purged with a submersible pump until a minimum of three casing volumes of water had been removed and temperature, pH, and electrical conductivity had stabilized to within 10% of the previous readings. This insured that formational waters were drawn into each well. All measured parameters were recorded on the appropriate field logs and are presented in Appendix B. Table 1 summarizes the field logs for the measured parameters. Thepum � hose, and electrical Ieads were decontaminated before and between each well P purging by washing the exterior with a solution of laboratory grade non-phosphate �! detergent and pumping at least 20 gallons of the solution through the pump and hose. The exterior of the pump, hose, and electrical leads were then rinsed with potable water and at American Geological Services, Inc. CA95DF 429 - 4