Post 4H Platform Abandonment - Shell Mounds Deposition, Santa Barbara County, California
Project Name: Post 4H Platform Abandonment - Shell Mounds Deposition, Santa Barbara County, California Services: Coastal Facility Permitting Client: Chevron
The professional staff of Padre prepared the technical and environmental clearance needed to fulfill permitting requirements for the permanent abandonment and removal of four offshore platforms (collectively known as the 4H platforms; including platforms Hope, Hilda, Hazel, and Heidi), and associated oil and gas pipelines located in state waters off the eastern Santa Barbara County coast in 1996. Permit-related documentation prepared included:
- Biological resource assessment focusing on marine and terrestrial flora and fauna inhabiting the waters surrounding the affected platforms and onshore pipeline regions;
- Assessment of the potential impacts because of project activities;
- Mitigation measures;
- Evaluation of seafloor conditions below the platforms to determine the extent and composition of discharged drilling-fluids and drilling muds and cuttings (analysis of current speeds and directions in the Santa Barbara Channel aided in the calculation of the extent and duration of turbidity originating from disturbance of sediments during abandonment operations and provided insight as to the projected direction of flow in the event of an oil spill during abandonment operations); and
- Air emission analysis of both criteria air pollutants and evaporative pollutants associated with equipment operations.
Following completion of the offshore decommissioning activities, Chevron conducted the required trawl test to demonstrate site clearance at the former platform sites. During these activities, it was determined that Chevron would be unable to meet this permit condition and that an amendment to the State Lands Commission (CSLC) and California Coastal Commission (CCC) permits would be necessary.