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2.0 GROUNDWATER MONITORING AND SAMPLING PROCEDURES Depth to water was measured in wells MW-4, MW-5 and MW-6 on July 24, 2002 prior to purging and sampling the first well Groundwater elevation measurements were made using a Solinst water level meter Well sampling field data sheets documenting ' field parameters collected during the well purging are provided in Appendix A Mr Jeffrey Wong of the EHD was on-site for a portion of the fieldwork At Mr Wong's request, following the purging and sampling of the first well, depth to water was also measured in the next well sampled immediately prior to purging The purpose of this task was to assess if a response to drawdown could be measured in adjacent wells During this sampling event, MW-6, MW-5 and MW-4 were purged and sampled in that order Based on water level measurements collected from MW-5 immediately prior to purging, the depth to groundwater decreased by 0 04 feet after purging well MW-6 The water level in MW-4, purged and sampled last, decreased by 0 05 feet following purging and sampling at MW-6 and MW-5 ' Prior to collecting groundwater samples, each well was purged using 2-inch diameter Grundfos submersible pump equipped with a check valve and new disposable polyethylene tubing Three casing volumes were purged from the wells and temperature, pH, and electrical conductivity readings were recorded after each casing volume was removed The readings were recorded on the field data sheets in Appendix A The water was clear in each well during and following purging No sheen, todor or other evidence of hydrocarbon contamination was noted Groundwater samples were collected from each well using a new disposable bailer New disposable latex gloves were donned prior to sampling each well The three groundwater samples were placed in containers appropriate for the selected analyses, labeled and placed on ice in a thermally insulated cooler pending delivery to the ' laboratory The samples were hand delivered to CLS Laboratories in Rancho Cordova, California on July 24, 2002 and analyzed for diesel range petroleum hydrocarbons (TPH-D) using EPA Method 8015M, preceded by silica gel cleanup The groundwater ' sample from MW-6 was also analyzed for total coliform using the 15-tube Standard Method 9221 1 ' P IPROJECTS\Safeway+L5283 GW—Report dx 2 GeOTrans,�n