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Broadbent&Associates,Inc. Well Abandonment Work Plan Vacaville,CA ARCO Station No.4932 March 10,2014 Page 3 1 than the auger originally utilized to install the well. The exposed well casing.will be cut-off and the remainder of the borehole will be overdrilled using a hollow stem auger. The cleared borehole will then be sealed with neat cement from the bottom upward to the depth of three feet below grade. The top three feet will be backfilled with clean uncontaminated fill material or cement grout and resurfaced to match the existing grade. The drill cuttings will be temporarily stored in 55-gallon drums until they are profiled and transported to an appropriate disposal facility under manifest. If utilities are found to be located in close proximity,over-drilling may not be possible and therefore an approval for pressure grouting will be requested. • Sealing materials will be placed in one continuous operation-unless field conditions require otherwise and prior authorization from SICEHD is obtained. For pressure grouting,the sealing materials will be placed under a pressure of up to 20 pounds per square inches (psi)for a period of up 10 to 15 minutes. It is anticipated that SJCEHD inspector will be onsite and will review the placement of sealing materials and its adequacy. • The sidewalk slab panels that will be affected during well abandonment will be replaced as required by the City of Stockton Public Works Department. • City of Stockton encroachment permits will be obtained prior to the work that will be performed in the City of Stockton public right-of-way. An access agreement with the adjacent parcel owner where a monitoring well is located will be attached along with the encroachment permit to the well permit application. • Groundwater displaced to the surface during grout installation will be pumped out to allow for EHD inspection and verification that the well is properly destroyed. The groundwater will then be containerized, profiled,and disposed of properly at a licensed disposal facility. Attached Table 1 provides the well construction details for the wells to be destroyed. Tables 2 and 3 present the current and historical site data. Work will be conducted by a State of California C-57 licensed drilling contractor. System Removal The inactive ozone sparge system located on the off-site property will also be removed as part of the closure process. The tubing connecting the wells to the ozone generating system will be removed during system removal.