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I ' 01 March 2002 AGE-NC Project No 95-0130 ' Page 4 of 10 ' Prior to well development, depth to water and total depth measurements were collected from each screened Interval utilizing a Solinst water level Indicator Thereafter, ground water was evacuated (purged) from the bottom of each monitoring well screened interval until ground water was visually sediment free Approximately 4 to 12 gallons of water were purged from monitoring wells MW-6 (C, D and E) and MW-7 (C, D and E) during development Ground water was not encountered in screen interval MW-7A and recharge was not documented from MW-6A, MW-6B and MW-713 (immediately purged dry) Temperature,pH and conductivity of purged ground water were measured at regular intervals utilizing an ICM water analyzer Purged ground water was containerized at the site in properly labeled DOT-approved model 17H 55-gallon drums Copies of monitoring well field logs for development activities are in Appendix C 2 6 WELL ELEVATION SURVEY On 25 October 2001, a state of California state-licensed survey engineer from Baumbach & Piazza Engineering, Inc surveyed a reference point on the top of MW-6 and MW-7 well casings at the site to the nearest 0 01-foot relative to the City of Stockton Bench Mark Datum 92 The results of the monitoring well survey are contained in Table 3 The surveying report(Baumbach&Piazza Job No lie 9797) is presented in Appendix D 2 7 INITIAL MULTI-LEVEL WELL GROUND WATER SAMPLE COLLECTION On 30 and 31 October 2001, water samples were collected from wells MW-6 (B, C, D and E) and t MW-7 (B, C, D and E) by lowering and raising a 318-inch outer diameter, length-discrete polyethylene hose equipped with a ball-valve water tip through the top chambers Into each specific water-charged screened section Prior to sample collection, approximately 0 1 to 3% gallons of ground water (a minimum of three casing-water volumes per well) were purged from the multi-level monitoring wells Ground water was not encountered in screen intervals MW-6A and MW-7A Ground water recharge was not documented from well MW-6B, however sufficient water sample was collected from the polyethylene hosing to fill the sample containers Temperature,pH and conductivity were measured for stabilization at regular purge-volume intervals from each well using a Hydac water analyzer Multi-level well purged ground water was containerized at the site in properly labeled DOT- approved model 17H 55-gallon drums Copies of monitoring well field logs for initial multi-level well water sample collection activities are in Appendix E Upon retrieval, the water samples were transferred into 40-m1 EPA-approved VOA vials containing . 0 5 ml 18% hydrochloric acid as a sample preservative The samples were logged on a chain-of- Advanced GeoEnviron mental,Inc