MC20 Spill Containment Effort Passes Million-Gallon Mark

Diver works to install the containment system at the MC20 site, 2018 (USCG)

Published Jul 19, 2022 11:03 PM by The Maritime Executive

The Coast Guard-led response to the Mississippi Canyon Block 20 oil spill - possibly the longest-running oil release in U.S. history - has captured more than one million gallons of oil as of mid-July. The milestone marks both the scale of the problem and the degree of success the government has had in addressing it. 

The leak at the site has been active since 2004, when Taylor Energy's MC20 platform off Louisiana was destroyed by Hurricane Ivan. Storm surge from the hurricane set off an underwater mudslide that knocked down the platform and buried its subsea infrasructure under 100 feet of sediment. 

From 2007-10, Taylor Energy completed well-plugging and remediation work at the site, but the task was incomplete. A 2015 investigation by Skytruth/AP found that the ongoing rate of leakage was higher than estimated, and the U.S. Coast Guard reopened its analysis of the well's status. In late 2018, the USCG's federal on scene coordinator took over control of the response and brought in an independent salvage team to install a containment system. The contractor has been recovering over 1,000 gallons a day ever since, and the Coast Guard reports that the job has been a success.

“The near elimination of the surface sheen and collection and removal of more than one million gallons of oil from the site over the previous three years is a major milestone in the Coast Guard’s efforts to contain the MC-20 oil spill that has affected the waters off the Gulf Coast for years,” said Capt. Kelly Denning, the Coast Guard’s Federal On-Scene Coordinator for the incident. “Though the containment system is considered a great success, the federal government is exploring all available response options, including to properly decommission the impacted wells on site.”

In a settlement agreement last December, Taylor agreed to liquidate all of its assets and transfer a $430 million remediation trust fund to the Department of the Interior. The funds will be used to properly decommission the leaking oil wells at the site.