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Deepwater Horizon Spill Assessment and Restoration Plan


  • The Deepwater Horizon marine oil spill was the U.S.’s largest.
  • Abt played a major role in the damage assessment.
  • We assisted in restoration planning and managing the comment process.
The Challenge

In 2010, an explosion on a Deepwater Horizon oil well in the Gulf of Mexico resulted in the largest marine oil spill in U.S. history. It required a massive response to minimize damage and protect the environment, with involvement by many federal and state agencies and other organizations. 

The Approach

Abt provided strategic litigation support; planning, implementation, and interpretation of the results of injury assessment studies; and restoration planning. We worked with experts to use remote-sensing technology to track the extent and duration of the oil footprint. The toxicological evaluations of oil effects were perhaps the largest suite of aquatic and avian toxicity studies ever conducted for a single incident. We also conducted a three-year recreational use study to assess changes in human use.

The Results

With the information, we engaged in restoration planning activities for trustee agencies, including developing methods and techniques to quantify potential restoration benefits for early restoration projects such as marsh creation, restoration of barrier islands, and oyster restoration. Our staff played a critical role in the release of the Programmatic Damage Assessment and Restoration Plan and Programmatic Environmental Impact Statement. We helped the trustees draft and review key restoration and injury sections and helped manage the public comment process. Learn more