FIELD DOCUMENTS - Laserfiche WebLink

Home Browse Search

Stockton Delta Water Supply Project WTP Well Demolition and Sanitary System Approval August 20, 2010 Page 3 WELL CLOSURE WORK PLAN The three existing wells described above will be demolished in accordance with California Well Standards as follows to protect the groundwater. Monitoring Well Due to the small diameter of the monitoring well, it will be drilled out with an 8-inch diameter hollow-stem auger to approximately one foot below the 82-foot well depth. The resulting borehole will be filled with a neat cement grout mixture from the bottom up,using a tremmie pipe. The grout fill will be stopped approximately 8 feet below the ground surface to allow construction of welded steel water supply pipelines above. Irrigation Well The casing of the existing 12" irrigation well will be perforated from approximately 10 feet below ground surface to approximately 90 feet below ground surface,then filled with 10.3 sack sand cement placed from the bottom up by tremmie, as described in the attached Well Destruction Permit application submitted to the San Joaquin County Environmental Health Department. The top five feet of the casing will be removed and the casing will be sealed with a mushroom cap. Domestic Well The casing of the existing 12"irrigation well will be perforated from approximately 10 feet below ground surface to approximately 90 feet below ground surface,then filled with 10.3 sack sand cement placed from the bottom up by tremmie, as described in the attached Well Destruction Permit application submitted to the San Joaquin County Environmental Health Department. The top five feet of the casing will be removed and the casing will be sealed with a mushroom cap. SUMMARY The demolition of the three existing wells described above will in accordance with California Well Standards and will provide expected protections for the groundwater. The planned on-site septic tank and leach£eld system will handle only standard types and volumes of typical domestic wastewater. No non-standard waste streams with elevated salts,fixed dissolved solids, or other chemicals will be discharged to this system. With the concurrence of the RWQCB,permit application review and approval procedures will be resumed with the San Joaquin County Environmental Health Department. CDM