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Levi ne•Fricke•Recon DRAFT <br /> by Henning is included in Appendix D. The video log contained the following <br /> significant observations about well LVMD #6: <br /> • vertical perforated casing was observed from 85 to 115 bgs and from 145 to 160 <br /> feet bgs <br /> • horizontal perforated casing was observed from 160 to the bottom of the well <br /> observed at 254 feet bgs <br /> 3.4.4.3 Well Abandonment <br /> According to SJC DPW records, well LVMD #6 was reportedly abandoned in 1992 by <br /> removing the 8-inch-diameter PVC casing, drilling out the filter pack, and perforating <br /> the 14-inch-diameter casing from 37 to 210 feet bgs with a downhole knife apparatus <br /> (Appendix F). Before well abandonment, material was reportedly bailed out of the well <br /> to a total depth of 248 feet bgs and the well as pressure grouted with neat cement from <br /> 248 feet bgs to ground surface (Appendices E and F). The total volume of grout that <br /> was pumped into the well was not reported. <br /> 4.0 CONCLUSIONS AND RECOMMENDATIONS <br /> The results of the public and private well survey, as discussed in this report, support <br /> the following conclusions: <br /> • In consideration of the direction of groundwater flow observed at the Site, the <br /> distribution of Hazardous Substances detected in groundwater samples collected <br /> from monitoring wells at the Site, and well construction and lithologic data for well <br /> COS #11, there is a potential for Hazardous Substances detected in groundwater at <br /> the Site to migrate to and possibly enter municipal supply well COS #11. However, <br /> as recent as December 1995, VOCs, including the Hazardous Substances, have not <br /> been detected in groundwater samples collected from well COS #11. LFR plans to <br /> sample well COS #11 in the first quarter 1997 as noted in the recommendations <br /> described below. To evaluate the potential for detected Hazardous Substances to <br /> migrate from Lincoln Center to downgradient municipal supply wells, the scope of <br /> the RI, as described in the RI/FS Work Plan, includes installation of A-, B-, and <br /> C-zone monitoring wells at a location downgradient from Lincoln Center, <br /> approximately midway between Pacific Avenue and well COS #11. Groundwater <br /> samples may be collected from additional municipal supply wells located <br /> downgradient from Lincoln Center, pending the results of groundwater samples <br /> collected from well COS #11 and the results of the plume perimeter investigation. <br /> • Based on the evaluation of well construction, lithologic data, groundwater elevation <br /> data, and analytical results of groundwater samples collected from Chevron and <br /> Exxon monitoring wells, the Chevron and Exxon monitoring wells may be useful <br /> for characterizing the groundwater quality and hydraulic characteristics of the Site. <br /> However, groundwater levels measured in the Exxon monitoring wells should <br /> Page 20 4111 WELL.AW AMI <br />