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MW7 is located in the sidewalk south across Douglas Boulevard (San Joaquin County) MW5, MW8, MWI1 and MW12 are located east across Pacific Avenue within the City of Stockton MW5 and MW8 are on City Property, MW11 is located in the Festival Cinema parking lot (Mann Theaters Corp property) and MW12 is located in the planter southwest of the Kragen Auto Parts store(property owned by Dr Sidney Kerston) WELL DESTRUCTION On September 25 - 28, 200I Western Geo-Engineers supervised Woodward Drilling, Inc in the destruction of aII groundwater monitoring wells (MW1 - MW13) and subsurface environmental laterals under the observation of San Joaquin County Public Health Services, Environmental Health Division (SJCPHS,EHD) All wells were destroyed in accordance with San Joaquin County - Well Standards 13 17 1 through 13 17 15, see Appendix B (Well Destruction Permits, Encroachment Agreements, Well Destruction Form, Well Boring Logs and Well Construction Logs) Pressure Grout Monitor Wells MW4, MW5, MW6, MW7, MW9, and MW12 were pressure grouted Prior to grouting the wells, depth to water and depth to bottom of well were measured If no obstructions were noted one inch PVC tremie pipe was then installed into the well to the total depth of the casing Once the tremie pipe was installed neat cement grout containing less than 5% bentonite was pumped through the tremae pipe completely filling the well to surface All displaced well fluids were captured at the surface and placed into 55 gallon DOT drums The tremae pipe was then removed and a pressure head with and adjustable packer was placed at the top of well casing and the packer expanded making a tight seal The pressure head was then attached to the grout pump and grout pumped until the pressure was higher than the pressure at the last noted grout flow/transfer movement This static pressure was allowed to stay on the well head for 30 seconds The pressure head was then removed The tremae pipe grout placement was only used on MW12 The onsite San Joaquin County Health Inspector allowed the grout to be placed directly to the well using the 2 inch diameter grout hose for the remainder of the well destructions The hydrostatic head of 30 plus feet of grout was determined to be enough pressure to force the well water and grout into the formation to provide a sufficient seal Once the grout reached the top of well casing the pressure head was attached and the grout pumped until the pressure was higher than the pressure at the last noted grout flow/transfer movement for the remaining wells Once the well had been pressure grouted, the traffic box and concrete pad were removed Using Woodward Drilling, Inc "Hydra-Vac" the upper 3 feet of the well was over-bored, using water jet and vacuum cutting a 22 inch diameter by 36 inch deep excavation The casing and neat cement seal exposed in the excavation was removed to within 6 inches of the base of the excavation Sand grout seal was then placed into the excavation covering the exposed casing/seal by at least one foot, from the 36 inch depth, usually to about the 18 inch depth MW5 and MW12 were situated in dirt areas and were backfilled from the 18 inch depth to surface with native soil SMW4, MW6, and MW9 were situated in asphalt areas The sand grout was extended to 6 inches of surface, then these areas were resurfaced with compacted road base and 4 inch thick hotpatch asphalt 2 R-603 sits restoration 11-2001