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Binayak Acharya Project 2074-00101 December 21, 1994 Page 2 from each boring were submitted to a state-certified laboratory for chemical analyses The samples were collected in stainless steel liners and sealed with Teflon® tape and caps The samples were labeled, placed on ice in a cooler, and delivered to the Nestle ' Quality Assurance laboratory in Dublin, Ohio with chain-of-custody documentation The laboratory certification number for the State of California is 1254 Boring MW-1 was converted to a groundwater monitoring well (MW-1) by installing 4-inch-diameter polyvinyl chloride (PVC) casing to a depth of 94.5 feet BGS A 20-foot section of screened casing was placed at the bottom portion of the well, extending above first-encountered groundwater detected at approximately 90 feet BGS during drilling activities Sand pack was placed in the annular space from the bottom of the well to approximately 1 foot above the screened interval Approximately 1 foot of bentonite seal was placed above the sand pack A cement grout seal was placed above the bentomte to approximately 1 foot BGS The top of the well was protected with a traffic-rated vault ' box set in a concrete seal and capped with a water-tight locking device Well construction details are presented in Appendix A Boring B-1 was backfilled to the ground surface with cement On November 21, 1994, well MW-1 was developed and sampled Depth to water was measured from the top of the well casing The well was developed using a surge block ' and the well was subsequently purged of at least four casing volumes until the temperature, electrical conductivity, and pH of the water had stabilized Following development, groundwater samples were collected from the well using a Teflon® bailer. The sample was poured from the bailer into a sample bottle, labeled, placed on ice, and transported to the Nestle Quality Assurance laboratory for cherrucal analyses. Field data sheets are presented in Appendix B Soil generated during drilling activities and water generated from steam-cleaning and well purging were drummed, labeled, and stored on site ' SUBSURFACE CONDITIONS The sediments encountered in borings MW-I and B-1 are predominantly sands (with clay, silt, or gravels) and of layers sandy and silty clay Boring MW-1 was terminated after encountering clay at a depth of 93 to 98 feet BGS Depth to groundwater was measured well MW-1 on November 21, 1994, and found to be approximately 72 feet BGS Exploratory boring logs are presented in Appendix A Field data sheets are presented in Appendix B ESJ/I 1PJ2120740010 1 AX-94 1Jt 2