Environmental assessment for the implementation of Exxon Valdez Trustee Council project no. 11100836 : pilot studies of bioremediation of the Exxon Valdez oil in Prince William Sound beaches Implementation of Exxon Valdez Trustee Council project no. 11100836 Pilot studies of bioremediation of the Exxon Valdez oil in Prince William Sound beaches

"This document is an Environmental Assessment (EA) of the potential impacts of implementing a pilot project to apply bioremediation methods in situ to breakdown and degrade subsurface oil remaining in beaches that were heavily impacted from the 1989 Exxon Valdez oil spill in Prince William Sound Alaska. The 1994 Environmental Impact Statement for the Exxon Valdez Oil Spill Restoration Plan along with the 2010 supplemental EIS to the plan, provide the context for proceeding with remediation efforts. The proposal calls for four test locations representing differences in beach geomorphology. At each location hydrogen peroxide and nutrients will be injected into pipes into the layer where oil remains. Previous studies have shown the oil layer is generally impermeable to flushing by wave and tidal changes, appears to be anoxic and nutrient poor, and liquids injected into the layer can move horizontally. The injected hydrogen peroxide is expected to break down rapidly into water and oxygen and along with the supplied nutrients, help promote bacterial degradation of the oil. The study will evaluate the efficacy of this approach and if can be applied on a broader scale to other oiled sites. Because this pilot project is part of a staged approach addressing the question of whether to proceed with more extensive effort to remove remaining oil, cumulative impact analysis and the decision to proceed to full scale remediation is deferred and will be addressed through a subsequent Environmental Analysis, based in part on the outcome of this study. As it stands the environmental impacts from this first stage effort is expected to be minimal and if effective, the treatment will remove potentially toxic lingering oil through a relatively low impact method. Not proceeding with the pilot project would leave natural recovery as the only viable option. Natural recovery is expected to take decades longer. The pilot project will require a special use permit from the U.S. Forest Service if storage sheds housing the pumping equipment and chemicals are placed above mean high tide. While not directly a part of this assessment, any terms and conditions required of the permit will have to be incorporated into the project plan"--Abstract.