Environmental Engineering and Remediation
Underground Storage Tanks, Environmental Assessments, Compliance, Other

Underground Storage Tank (UST) Removal

Coastal Campus, Naval Base Coronado (NBC), Coronado, CA

GCE was contracted to remove an approximately 7,500-gallon steel UST that was discovered during construction of the Coastal Campus at NBC and restore the site. The UST was removed under County of San Diego Department of Environmental Health (DEH) permit and in the presence of DEH Inspector who decided on the location of soil samples.

This project included the development of an Accident Prevention Plan (APP) and Site-specific Safety and Health Plan (SSHP) to guide the UST removal and site restoration. Once the planning documents were approved, GCE prepared and submitted DEH UST Closure Permit Application. Upon approval of the UST Closure Permit by DEH, GCE mobilized to the site to conduct UST removal and site restoration fieldwork.

GCE performed the following specific UST removal and site restoration work:

  • Utility clearance. The area around the UST was surveyed for underground utilities by an independent utility locator service to ensure each boring location is clear of existing underground utilities.
  • UST Cleaning. Debris in the UST was removed and transported to an appropriate facility for disposal. The remaining residual fuel and liquids were removed from the UST and transported to an appropriate facility for disposal or recycling. The UST was triple rinsed and certified as gas free and safe for removal.
  • UST Removal. The UST was removed from the resultant excavation. The removed steel was hauled off site for disposal at a metal recycling facility.
  • Soil Sampling. Soil samples were collected from the former UST excavation at the direction of an on-site DEH Inspector. The soil samples were analyzed for total petroleum hydrocarbons, and fuel related volatile organic compound.
  • Site Restoration. Following completion of sample collection and analysis, the former UST excavation was backfilled with pea gravel from the bottom of the excavation to one foot below ground surface. The final one foot will be backfilled with clean compacted fill soil.

A UST Closure Report was prepared documenting the results of the UST removal and site restoration. The UST Closure Report was prepared in accordance with conditions outlined in the DEH UST Closure Permit, and submitted to the DEH, the client, and the Navy.