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�1 r • <br /> DRAFT Levine-Fricke-Recon <br /> and estimated volume of grout that could be pumped into this space has not been <br /> resolved, the reported volume exceeds the minimum volume estimated for the entire <br /> well and annular space. (LFR contacted SJC DPW to clarify discrepancies that <br /> were identified during the well abandonment evaluation. However, SJC DPW <br /> requested that all inquiries be made to SJC Counsel. SJC Counsel has not <br /> responded to our inquiries. We are still trying to obtain additional information <br /> about this well.) <br /> ! 3.4.4 Well LVMD #6 <br /> 1 <br /> i <br /> 3.4.4.1 Well Construction <br /> According to the Water Well Drillers Report obtained from SJC DPW, well LVMD #6 <br /> was drilled in 1958 using the cable tool drilling method. Details of original well <br /> i construction, well repair, and abandonment of well LVMD #6 are presented in Figure <br /> 12. The total depth of the boring was 266 feet bgs (Appendix A). The well was <br /> completed with a 14-inch-diameter steel casing from the ground surface to 262 feet <br /> bgs, which was perforated from 210 feet bgs to 262 feet bgs. The borehole was left <br /> open and uncased from 262 feet bgs to 266 feet bgs. A cement sanitary seal was <br /> installed from ground surface to 40 feet bgs. Comparison of lithologic data collected at <br /> the Site to well construction data for well LVMD #6 indicates that the perforated <br /> interval and open borehole of well LVMD #6 appear to have been located in the <br /> C-zone aquifer (LFR 1996a). <br /> 3.4.4.2 Well Repair and Video <br /> In 1984, well LVMD #6 was repaired by SJC DPW reportedly to mitigate a sand <br /> production problem in the well by installing 8-inch-diameter PVC well screen and <br /> casing to a depth of 254 feet bgs (Appendix F). The vertical well screen was located at <br /> depths of 85 to 115 feet bgs and 145 to 160 feet bgs. The horizontal well screen was <br /> located from 160 to 254 feet bgs. Although the total screened interval in the PVC <br /> casing ranged in depth from 85 to 254 feet bgs, the effective screen interval for the <br /> repaired well was the same as the original well construction because additional <br /> perforations were not cut in the 14-inch-diameter casing. A filter pack was reportedly <br /> installed between the 14-inch-diameter steel casing, which was part of the original well <br /> construction, and the 8-inch-diameter PVC casing from 165 to 262 feet bgs. According <br /> to the plans and specifications, the PVC well casing was not "secure" within the 14- <br /> inch-diameter steel casing, apparently indicating that the PVC casing was not grouted <br /> in place (SJC DPW 1992). <br /> In 1990, KJC supervised a video survey of LVMD#6 conducted by Henning <br /> (LH 1989; KJC 1991b). Reportedly, the purpose of the video was to evaluate the <br /> integrity of the repaired well inside the PVC casing and the possible source of sand <br /> still being produced from the well (KJC 1991b). A summary of the video log prepared <br /> F <br /> `s <br /> , <br /> } <br /> 4111WELL.AW AMI Page 19 <br />