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Western Oil and Spreading,Acampo Plant Site Well Destruction Scope of Work The following activities will be performed to abandon the wells: Onsite Wells: MW-1,MW-2 MW-3 and MW-4 • Monitoring wells MW-1 and MW-3 will be grouted using a pressurized"Chem- Grout-Machine'with a rafted pressure of 150 pounds per square inch(psi). From the top-of-casing,a neat cement mixture will be pushed through the monitoring well screen and into the surrounding formation(approximately three well volumes). After the monitoring wells are filled with the grout mixture,the well boxes will be removed using an air-compressed jackhammer. First,a hole at least 1 foot larger in diameter than the originally drilled hole shall be excavated around the outside of the well casing to a depth of 3 feet BGS,then the well casing shall then be cut off 6 inches above the bottom of this excavation and removed. The grout used to fill the well shall be allowed to spill over into the excavation,during the sealing operation,and fill it for a thickness of 1 foot and form a"cap"that has a diameter of at least 1 foot greater than the diameter of the originally drilled hole. The hole will be covered using like material to surface grade. • Monitoring wells MW-2 and MW-4 will be overdrilled and removed using an auger drill rig equipped with 8-inch diameter hollow stem augers. This will include the removal of the PVC piping,bentonite,sand,grout,and well box. The concrete and metal will be placed in the regular trash;the remaining material will be spread on site in an area of minimal erosion activity. A neat cement grout will be used as backfill material to approximately 1 foot BGS. The hole will be covered using like material to surface grade. Offsite Wells: MW-5,MW-6 and MW-7 Monitoring wells MW-5,MW-6,and MW-7 will be grouted using a pressurized "Chem-Grout-Machine"with a rated pressure of 150 pounds per square inch (psi). From the top-of-casing,a neat cement mixture will be pushed through the monitoring well screen and into the surrounding formation(approximately three well volumes). After the monitoring wells are filled with the grout mixture,the well boxes will be removed using an air-compressed jackhammer. First,a hole at least 1 foot larger in diameter than the originally drilled hole shall be excavated around the outside of the well casing to a depth of 3 feet BGS,then the well casing shall then be cut off 6 inches above the bottom of this excavation and removed. The grout used to fill the well shall be allowed to spill over into the excavation,during the sealing operation,and fill it for a thickness of 1 foot and form a"cap"that has a diameter of at least 1 foot greater than the diameter of the originally drilled hole. The hole will be covered using like material to surface grade. \\Eureka\projects\2007\007152-WOS\CorrOut\ltr\007152-Wel]DestScopeForPermit.doc