ARCHIVED REPORTS XR0006244 - Laserfiche WebLink

Home Browse Search

2.0 GROUNDWATER MONITORING AND SAMPLING PROCEDURES ' Depth to water was measured in wells MW-4, MW-5 and MW-6 on April 30, 2002 prior to purging and sampling the first well Groundwater elevation measurements were made using a Solinst water level meter The water level measurement field data sheets 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 03 feet after purging well MW-6 The water level in MW-4, purged and sampled last, did not change following purging and sampling at MW-6 and MW-5 Prior to collecting groundwater samples, each well was purged using a new disposable bailer At least 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 ' Between 40 and 60 gallons of water was removed from each well prior to sampling The water was clear in each well following purging Groundwater samples were collected from each well with the same bailer used for purging 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 May 1, 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 i � i ' GeoTrans,Inc