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Union Ice Company 1320 West Weber Street, Stockton, California April 30, 1993 Phase I Investigation Deport, Brine Release Page 2 3.0 Well Construction and Sampling The wells were installed by Pierson Drilling Company C57 License # C521617 using an VA" OD hollow stem auger. Soil samples were obtained using a California modified split spoon sampler with brass sleeves. Samples were obtained at depths of 15' and 30' in each of the wells. The samples were preserved in ice chests containing Blue Ice and sent via Greyhound to Geo Monitor Labs in Hesperia, California for analysis of total chromium. The borings were logged by Craig Hyde, Geologist under the supervision of Lee DeLano PE. The monitoring wells are constructed using 2-inch PLIC casing, with slitted (0.020 inch slits) for the screened intervals. Well construction logs are in the appendices of this report. Groundwater samples were obtained by HKM, Inc., a firm specializing in well development and sampling. The wells were developed until the extracted water was clear and the pH, electrical conductivity, and temperature were stabilized. Water from the development process and sampling process is contained on site in properly marked 55 gallon drums. Field notes from the sampling event are contained in the appendices of this report. 4.0 Report of Findings Significant groundwater production was observed at approximately 28 feet below the ground surface where a permeable sand was encountered. The site is surrounded on 3 sides by water bodies, and the level of groundwater in the wells is currently between nine and ten feet below the ground surface. Soil samples from the monitoring well 10 at the 15' depth had a total chrome concentration of 8.57 mg/kg and at the 30' level 11.82 mg/'kg total chrome. Well 11 had total chrome concentrations of 10.22 mg/kg at t5' and 7.0 mg/kg at 30'. Well 1.2 had total chrome concentrations '10.36 mg/kg at 15' and 8.46 mg/kg at 30'. The analysis of groundwater samples from the wells indicate that well 10 has 0.335 mg/l of total chrome, well 11 has 0.302 mg/1 of total chrome, and well 12 has 0.278 mg/1 of total chrome. All lab data and chain of custody documents are in the appendices of this report.