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2 3 3 Soil Sampling, Well Development and Wellhead Elevation Survey s ' During the drilling of MW-8A and below 50 feet in MW-8B, soil samples were collected at 5-foot intervals using a modified California split-spoon sampler lined with stainless steel sleeves A field ' geologist logged all soil samples for hydrogeologic and lithologic characteristics according to the Unified Soil Classification System and screened each sample for any organic vapors using a photoionization detector (PID) The monitoring well logs are included as Appendix C Given that the extent of impacted soil had previously been defined, no additional soil samples were submitted for laboratory analysis MDE developed both of the wells, following the placement of the sand packs and prior to the installation of the well seals Well development included surging with a surge block and periodic purging with a bailer, until at least five well volumes had been removed and/or after groundwater temperature, pH and electrical conductivity had stabilized ' During April 2002, Morrow Surveyors (California Licensed Land Surveyor#5161 surveyed all of h Y } y to existing and newly-installed wellheads The elevations of several of the original wellheads were compromised during remediation system construction Morrow Surveyors measured the elevations of the tops of well casings to the nearest 0 01 foot, referenced to the city of Stockton Benchmark #20-B Morrow Surveyors also located the wells and other site features The surveyor's report is included as Appendix D ' 2 3 5 Groundwater Monitorin-q, Sampling and Analysis ' On March 28, 2002, Ramage Environmental monitored and sampled the new and existing wells, and collected a groundwater sample from the nearby cemetery irrigation well #2 Monitoring well MW-1 was not monitored or sampled due to damage at the wellhead The depth-to-groundwater was monitored in each of the other wells using a water level indicator ' capable of measurements to within 0 01 foot Following groundwater level measurements, each of the wells was purged and sampled The wells were purged with a pump and dedicated disposable tubing until at least three well casing volumes were extracted and/or after groundwater temperature, pH and electrical conductivity values had stabilized Following recharge, groundwater was sampled from the wells using dedicated and disposable bailers and laboratory-supplied containers The ' irrigation well was purged until the pump was activated and sampled from the wellhead Each sample was transported in an iced cooler with chain-of-custody documentation to Kiff Kiff analyzed ' each sample for TPH-as-gasoline, BTEX, MTBE, DIPS, ETBE, TAME, TBA, and 1,2-DCA by EPA Method 8260B . 10