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GeoHydrologic Consultants, Inc approved by the SJCEHD Well EW-5D was installed to a total depth of 85 feet bgs, well ' EW-5S was drilled to a total depth of 60 feet bgs, and VW-5 was installed to a total depth of 50 feet bgs Groundwater was encountered at approximately 49 feet bgs during drilling activities A copy of the well permits is included in Appendix B All work was performed in accordance with the procedures that Thrifty described in their Workplan for Well Abandonment/Installation of Groundwater wells and Pilot Testing dated November 12, 2004, and in accordance with the County of San Joaquin well installation standards 1 4.1 Well installation ' Groundwater extraction wells EW-513 and EW-5S, and soil vapor extraction well VW-5 were installed by West Hazmat Drilling Corporation of Anaheim, California Well EW- 5D was installed to a depth of 85 feet bgs, and was screened with four-inch diameter ' schedule 40 AVC having 0 010-inch slotted well screen from the total depth to 65 feet bgs A sand pack (#2112) was placed around the perforated section of the well from the total depth to 63 feet bgs Bentonite grout was placed from the top of the sand pack to ' three feet bgs The well was protected with a traffic-rated flush well box set in cement, finished to the surface ' Well EW-5S was installed to a depth of 60 feet bgs, and was screened with four-inch diameter schedule 40 PVC having 0 010-inch slotted well screen from the total depth to 40 feet bgs A sand pack (# 2/12) was placed around the perforated section of the well ' from the total depth to 38 feet bgs Bentonite grout was placed from the top of the sand pack to one and one-half feet bgs The well was protected with a traffic-rated flush well box set in cement, finished to the surface ' Monitoring well MW-5 was abandoned by overdrilled to total depth plus one foot (91 feet) using 10-inch hollow-stem augers and a ten-foot steel lead rod which centered the augers over the existing well casing The borehole was then backfilled with medium grade bentonite chip to 52 feet bgs Well VW-5 was installed to a depth of 50 feet bgs, and was screened with two-inch diameter schedule 40 PVC having 0 010-inch slotted well screen from the total depth to 25 feet bgs A sand pack(# 2112) was placed around the perforated section of the well from a depth of 52 feet bgs to 23 feet bgs Bentonite chips were placed from the top of the sand pack to 20 feet bgs and a bentonite grout seal ' extended to three feet bgs The well was protected with a traffic-rated flush well box set in cement, finished to the surface One July 2, 2005, GHC removed the 12-inch diameter flush mount well box at the wellhead of VW-5 GHC then dug up the former two-inch diameter PVC vapor extraction line which was cut at the time of abandonment of MW-5, reconnected it to VW-5, with a ' two-inch diameter PVC isolation ball valve inline prior to connecting the line at the wellhead An additional two-inch line was teed from the main vapor extraction line prior to the isolation valve and reconnected to the former two-inch diameter vapor extraction ' line connecting TB-4 and TB-6 back with the vapor extraction system A second two- inch diameter AVC isolation ball valve were added to this line inside the well box for . VW-5, so that these two wells could be isolated from the system The VW-5 wellhead ' TOC 171 Pdot Study Page 6