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Mr Jeff Wong Page 4 of 10 Well Development and Surveymg The depth to water below the tops of the well casings (btoc) was measured prior to the development of the newly installed wells The accurate depths to water in the casings of wells MW13C and MW14B could not immediately be determined due to remnant drilling mud in the casing Wells MW10 through MW14C were developed by surging and pumping until tubidrty was minimized A Ground Zero technician monitored and developed wells MW10 through MW12 between October 17 and October 20, 2003 The wells were developed using a Waterra Inertial Pump System V&W developed well MW 14B on October 20, 2003 and well MW 13 C between October 21 and October 23, 2003 The physical parameters of pH, conductivity, temperature, and relative turbidity were measured during well development Purged groundwater was placed in DOT-approved 55-gallon drums pending disposal Well development notes are included in Attachment B On October 28, 2003 Morrow Surveying surveyed the latitude and longitude of the newly installed wells relative to the North American Datum (NAD83), and surveyed the wellhead elevations relative to San Joaquin County Benchmark ERM 237 A site map showing monitoring well locations, latitude and longitude coordinates and wellhead elevations is included in Attachment C Groundwater Sampling Groundwater levels in all site wells were measured on October 17, 2003 Groundwater elevation was calculated by measuring the depth to groundwater in each well and subtracting the measured depth from the respective well head elevation The measured depth to groundwater in the shallow monitoring wells ranged from 66 23 feet btoc in well MW 1 (corrected for the presence of free product) to 68 69 feet btoc in well MW11 (completed at approximately 3 feet above ground surface) The groundwater levels in wells MW9B (completed at approximately 3 feet above ground surface) and MW 1413, which were completed in the B Zone aquifer, were measured at approximately 67 29 feet btoc and 59 12 feet btoc, respectively The groundwater level in well MW13C (completed at approximately 3 feet above ground surface), which was completed at a depth of approximately 222 feet bgs, was measured at 57 80 feet Wells MW10, MW11, MW12, and MW14B were sampled on October 20, 2003 Well MW13C was sampled on October 23, 2003 Groundwater samples were collected from each well after the groundwater level in the respective well had recovered at to least 80% of the pre- purged/development levels The samples were collected using a disposable bailer, transferred to the appropriate containers, sealed, labeled, and immediately placed in an ice chest cooled to a 4 temperature of approximately C The samples were transported to Argon under chain of custody protocol for the analysis of TPHg, BTEX, and oxygenated gasoline additives, including the lead scavengers ethylene dibromide (EDB) and 1,2-dichloroethane (1,2-DCA) using the appropriate EPA methods Soil Vapor Extraction Test On October 22,2003 Del-Tech Geotechnical performed short-term vapor extraction tests (VETs) on wells MW 1 and VW 1 The VET equipment consisted of an internal combustion (IC) engine equipped G\GROUNDZEITULEBURG\ReportFWSA_Mud wells Report 2 doe