Groundwater Monitoring Well Destructions, Marine Corps Base (MCB) Camp Pendleton, CA.

This task order included the abandonment of 102 groundwater monitoring wells and site restoration from three UST sites at Camp Pendleton.

The objective of this project was to destruct groundwater monitoring wells at various Underground Storage Tank (UST) sites at MCB Camp Pendleton in accordance with San Diego County Department of Environmental Health (DEH) requirements. A total of 102 groundwater monitoring wells were abandoned from three Leaking Underground Storage Tank (LUST) sites at MCB Camp Pendleton. The wells were installed to monitor groundwater downgradient of former UST locations, 22 Area (MCX Gas Station), 24 Area (UST 2459), and 43 Area (UST 43302).

Well destruction permits were obtained from DEH, as required by San Diego County Code, Title 6, Division 4, prior to the start of field activities. Each groundwater monitoring well location was identified by the traffic-rated well cover or vault protecting the wells. Dig Alert was notified prior to groundwater monitoring well destruction activities to have all known existing underground utilities identified and marked. A subsurface operations submittal was sent in to MCB Camp Pendleton Public Works Center for utility clearance identifying the well locations prior to the start of field activities, and an independent utility locator service was utilized to ensure each boring location was clear of existing underground utilities. A traffic plan was prepared and approved by MCB Camp Pendleton prior to the start of well destruction.

All wells had the surface completions removed, and the wells were over drilled using a hollow stem auger drill rig to remove the casing, filter pack, bentonite seal, and cement. Each boring was backfilled with cement grout. The surface was restored using 4,000 psi concrete. A Well Destruction Report was prepared and submitted to DEH within 60 days of the completion of field activities.