Laserfiche WebLink
Mr Ron Rowe <br /> C A B R I A July 7, 1999 <br /> . INVESTIGATION PROCEDURES <br /> j <br /> Cambria's scope of work for the investigation included performing a step-drawdown pumping <br /> test and a constant-rate pumping test on extraction well EW-1 Groundwater samples were <br /> collected at intervals throughout the pumping tests and after the pumping tests <br /> Personnel Present Staff Engineer Wayne Chiu of Cambria directed the pumping tests, <br /> working under the supervision of California Registered Professional <br /> Civil Engineer Owen Ratchye Ron Rowe of the SJCPHS was onsite for <br /> part of the fieldwork <br /> i <br /> Drilling Company Gregg Drilling, Inc of Martinez, California (C-57 License #485-165) <br /> was onsite to install and operate the pump <br /> Pump Test Dates May 4 and 5, 1999 <br /> GROUNDWATER EXTRACTION TESTING <br /> On May 4 and 5, 1999, Cambria performed pumping tests on 4-inch diameter extraction well <br /> EW-1 Extracted groundwater was collected in two Baker tanks The Baker tanks were then <br /> �} emptied into vacuum trucks by ECI and the water was transported to the Shell refinery in <br /> Martinez for disposal <br /> Pumping Test Procedures On May 4, 1999, a step-drawdown test was performed for 2 hours <br /> and aborted due to equipment problems A second step-drawdown test was performed for 2 2 <br /> hours and recovery was monitored for 14 hours The depth to water was periodically measured <br /> throughout the test in wells EW-1 and MW-i using pressure transducers <br /> On May 5, 1999, a constant-rate test was performed for 9 hours Recovering water levels were <br /> then measured for 125 hours The depth to water was periodically measured throughout the test <br /> using pressure transducers in extraction well EW-1, and observation wells MW-1, EW-2, and <br /> MW-2, which are located 42 8, 33 1, and 53 5 feet from well EW-1, respectively Pumping test <br /> data and results are presented in Attachment A Cambria's Standard Operating Procedures are <br /> presented in Attachment B Groundwater samples were collected from well EW-1 during the <br /> step-drawdown test, at the beginning of the constant-rate test, and at the end of the constant-rate <br /> test and were analyzed for <br /> • TPHg by EPA Method 8015, and <br /> • BTEX and MTBE by EPA Method 8020 <br /> Analytical results are presented to Attachment C <br /> 2 <br />