The First Circuit Court of Appeals has ruled that a U.S. Coast Guard navigation rule for Buzzards Bay, Massachusetts, which rule prohibited the application of state environmental law to some tanker activities in the bay, violated NEPA. U.S. v. Coal. for Buzzards Bay, No. 10-1664 (1st Cir. 5/17/11). So ruling, the appellate court reversed a district court determination that the Coast Guard had the authority to preempt provisions of the Massachusetts Oil Spill Prevention Act relating to manning and escort requirements in the bay. U.S. v. Massachusetts, No. 05-10112 (D. Mass. 3/31/10). The First Circuit held that the Coast Guard acted improperly when it relied on a categorical exclusion to decide it did not need to perform an environmental assessment or prepare an environmental impact statement in developing the 2007 navigation rule. The court therefore ordered the district court to remand the matter to the Coast Guard for further proceedings consistent with the opinion.