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MW7 was situated in the San Joaquin County sidewalk The sand grout was extended to 8 inches of surface The 4 foot by 5 foot concrete sidewalk flag containing the well was then removed and this arca was resurfaced with compacted road base and 6 inch thick concrete matching the existing sidewalk Pressure Grout Monitor Well MWI 0 MWI0 is within the new UST area and was damaged during the excavation work necessary to install the new UST's The casing was repaired by W A Craig Inc The 12 inch PVC conductor and 4 inch well casing were cut off 6 inches above the then existing UST backfill level, approximately 4 feet below surface This well was then pressure grouted as described above A 24 inch diameter by 18 inch deep "Sonotube" was then centered over the well and the sand grout plug placed into the ` Sonotube" completely filling it Drilling out - tremie grout Groundwater monitoring wells MWI, MW2, MW3, MW8, and MW13 were installed in contaminated soil and MWI I contained a blockage at approximately 45 6 feet below surface when being sounded In accordance to the requirements for well destruction these wells were destroyed as follows Remove the traffic box and concrete pad, drilling out the entire well system plus one foot deeper than the original boring (casing, filter pack and sanitary seal), and then fill the excavation with neat cement containing 5% bentonite by tremie method to the existing surface MWI, MW2, MW3 and MW13 were situated in asphalt areas The grout was extended to 6 inches of surface, then these areas were resurfaced with compacted road base and 4 inch thick hotpatch asphalt MWI 1 was situated in a planter Potting soil was used to backfilled from the 18 inch depth to surface REMEDIATION SYSTEM AND LATERALS All above ground remediation equipment was removed for disposal or reuse The below ground PVC pipe laterals that remain were backfilled with neat cement and left in place The PVC lateral from the treatment compound to the sewer clean out was exposed just north of the sewer clean out, cut and the clean out side plugged with a PVC cap The vapor extraction laterals from near MW2 to MW3 and MW13 were exposed at the wells and backfilled with neat cement The vapor extraction laterals from the UST excavation to MW2 area were removed The vapor extraction laterals within the UST excavation to the treatment compound were removed ENCROACHMENT AND PERMITS Well destruction permits were obtained from SJCPHS, EHD and the workplan approved prior to destroying any wells Also encroachment agreements and/or permits were obtained from the property owners that the wells are situated on and/or, the City of Stockton and the County of San Joaquin, see Appendix B 3 R-603 site restoration 1 1-2001