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APPENDIX A SAMPLING AND ANALYSIS PROCEDURES Subjective Analysis of Monitoring Wells Groundwater samples were collected for subjective analysis from just below the air-fluid interface in the monitoring wells by lowering approxurlately half the length of a clean Teflon' bailer through the interface The bailer was retrieved and the water sample examined for floating product, sheen, or other subjective evidence of hydrocarbons Measurement of the Depth to Groundwater in Monitoring Wells The depth of the groundwater surface in the monitoring wells was measured from the top of the well casing to the nearest 0 01 foot with a Soloist water level indicator . Groundwater Sampling The static water level in each well was measured to the nearest 0 01 foot with a Sohnst electric water level indicator cleaned with a laboratory-grade, non-phosphatic detergent and deionized water before use in each well. A clean bailer was used to obtain a sample from the surface of the water in the well for a subjective analysis of hydrocarbons The sample was retrieved and visually examined for floating product, sheen, color, and clarity Approximately three casing volumes of groundwater were purged from the wells using a stainless-steel, electrical, submersible pump The pump, cables, and hoses were cleaned with a laboratory-grade, non-phosphatic detergent and water before use in each well. The wells were purged until withdrawal was of sufficient duration to result in stabilized pH, temperature, and electrical conductivity of the water, as measured by portable meters calibrated to a standard buffer and conductivity standard The wells recovered to more than 90 percent of the static water level within 5 minutes of turning off the pump The groundwater purged from the wells was temporarily stored in 17E, steel, 55-gallon liquid waste drums approved for this use by the Department of Transportation Before collecting each groundwater sample, the geologist cleaned the Teflon bailer with a laboratory-grade detergent and rinsed it with tap water and demonized water Hydrochloric acid was added to the sample vials as a preservative A sample of the formation water was then • collected from the surface of the water in each of the wells with the Teflon bailer and slowly transferred to laboratory-cleaned sample containers SA(;\N\P12\2605\26051010 1 C 5-97\prz 1 A-1 Rev 0,8112/97