Estimated air emissions savings from partially removing and reefing the jacket of a large California oil and gas platform

Abstract

This paper estimates the potential emission savings that could be achieved if the jacket of a large California oil and gas platform is partially removed and converted to an artificial reef rather than fully removed. The platform selected for study is Platform Harvest which is located on the federal Outer Continental Shelf (OCS) offshore Point Conception in Santa Barbara County, California. Platform Harvest, a large steel jacketed structure located in 675 feet of water, ceased production in 2015 and plans are now being developed for removing the structure. Under the partial removal option, the upper sections of the jacket would be removed to a depth of 85 feet below the ocean surface with the remainder left in-situ to serve as an artificial reef. The full removal option involves removing the entire jacket by cutting the jacket legs and piles off 15 feet below the seabed, cutting the jacket into sections for lifting by a heavy lift vessel, and transporting the jacket components on cargo barges to shore for recycling or disposal. The results of the study show the partial removal jacket option would result in a 10-fold reduction in emissions of nitrogen oxide, sulfur dioxide, green-house gases, and other criteria pollutants as compared to the full removal option.