Project Schedule

Under the Cleanup or Abatement Order (CAO) No. 98-38 issued by the Central Coast Regional Water Quality Control Board on April 3, 1998 and revised on November 6, 1998, Phase I remediation activities were required to be completed by the end of 2002. The Regional Water Quality Control Board approved a revision to the schedule on October 26, 1999, extending the deadline to complete excavations until such time that soil disposition issues are resolved.

Phase I CAO remediation activities include characterization, excavation, product recovery, pilot tests and treatment of affected soil (see Phase I activities). Decommissioning activities (i.e., the removal of abandoned pipelines and unused surface facilities) is largely complete. Completed activities and the schedule for completing all remaining Phase I CAO remediation activities are described below.

Past Activities:

  • Horizontal biosparging systems were installed that inject air into the saturated zone to enhance biological activity.
  • A pilot Land Treatment Unit (LTU) was constructed and operated. In the LTU, nutrient amendments and oxygen are tilled into the affected soil so naturally occurring bacteria within the soil can break down the hydrocarbon contamination.
  • Excavations of the first group of the Beach Sites (5X West, LeRoy 3 Sump, and 8X Sump) were completed by the end of 1999. For these excavations, sheet pile was driven into the ground around the perimeter of excavation sites so hydrocarbon-affected soil could be removed and replaced with clean soil.
  • The C8 Excavation was completed during the summer of 2000. Restoration activities and installation of an ecoremediation system at the C8 site was completed in the winter of 2000.
  • Excavations of the second part of the Beach Sites (5X East, A2A, 5X Road, LeRoy 6, and A1/2X) were initiated in September 2000 and were completed in February.
  • In 2002-2004, Unocal tested in situ hot water and steam flooding as a potential remediation alternative to excavating to remove petroleum hydrocarbons from impacted soil. The Pilot Test was in operation for 5 months, and was followed by a scale-up study to assess the possibility of using the technology on a site-wide basis.
Future Activities:
  • Phase I Activities - The Supplemental EIR was certified by the San Luis Obispo Planning Commission in July 2005, but excavation of the remaining Phase I CAO sites cannot begin until all agency permits and approvals have been obtained. Remaining sites include: B12/C12, B2-3, L11/M12 Sump, TB1, A5A/A5 Sump, TB4 Sump, M4, D14 Sump, B11 Sump, M2, C7 South, B6, and, if required, C2 and N12. (See Site Map)
  • Wetland Restoration - Of the remaining Phase I excavation sites, none would disturb wetland habitats (B2-3, B11, B12/C12, D14, L11, M2, M4, M12 and TB1). Three other sites (B3A, B6 and N12) do not involve disturbance to wetlands, but wetland creation/restoration activities are proposed for these sites. (See Site Map, linked above.) Impacts to wetlands by excavation activities must be mitigated by creation of new wetlands or restoration of existing wetlands at a created-to-disturbed ratio of 4:1. Details may be found in the Wetland Restoration and Mitigation Plan.
  • Phase II Activities - Phase II activities are under development in partnership with the RWQCB and other agencies. Emphasis of these activities will be on net environmental benefit.