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Levine-Fricke-Recon a J♦ DRAFT ` estimated volume of grout that could be pumped into this space has not been resolved, the reported volume exceeds the minimum volume estimated to fill the well casing. 3.4.3 Well LVMD #4 3.4.3.1 Well Construction According to the Water Well Drillers Report obtained from SJC DPW, well LVMD #4 was drilled in 1980 using the cable tool drilling method. The well installed in 1980 replaced a previously abandoned well. The well location, well construction, and abandonment procedures for the original well are not known. (LFR contacted STC DPW to clarify discrepancies that were identified during the well abandonment evaluation. However, STC DPW requested that all inquiries be made to STC Counsel. SJC Counsel has not responded to our inquiries. We are still trying to obtain additional information about this well.) Details of well construction and abandonment of replacement well LVMD #4 are presented in Figure 11. The total depth of the boring was 205 feet bgs (Appendix A). The well was completed with a 14- inch-diameter outer steel casing from the ground surface to 70 feet bgs and a 10-inch- diameter inner steel casing from the ground surface to 130 feet bgs. No perforated interval was indicated on the Water Well Drillers Report. The borehole was left open and uncased from 130 feet bgs to 205 feet bgs. A cement, sanitary seal was installed from the ground surface to 70 feet bgs. Comparison of lithologic data collected from the Site to well construction data for well LVMD #4 indicates that the open borehole of well LVMD #4 appears to have been located across the lower 15 feet of the B-zone aquifer, the entire B/C aquitard, and in the upper 40 feet of the C-zone aquifer (LFR 1996a). 3.4.3.2 Well Abandonment According to SJC DPW records, well LVMD #4 was reportedly abandoned in 1992 by perforating the 10-inch-diameter inner casing from 68 to 130 feet bgs (Appendix F). Although, the method of perforation was not specified on the record drawings, the plans and specifications required either a star or wheel perforation or a knife perforation (SJC DPW 1992). Material was reportedly bailed out of the well before abandonment and the well was pressure grouted with a sand-cement grout from 129 to 177 feet bgs, and with a neat cement grout from 129 feet bgs to ground surface (Appendices E and F). Based on the dimensions of the well documented on the record drawings, the estimated minimum volume of grout that would be necessary to fill this well is approximately 3.1 cubic yards. The total volume of grout that was pumped into the well was not reported. However, the record drawings indicated that a 3-inch-wide annular space around the 14-inch-diameter outer casing was filled with 12 cubic yards of grout to a depth of 49 feet bgs. The estimated volume of grout that could be pumped into the 3-inch annular space is approximately 1 cubic yard. Although the discrepancy between the reported Page 18 4111WELL.AMI:AM1