Pre-spill precautions
In February 2009, BP filed a 52-page exploration and environmental impact plan for the Macondo well with the Minerals Management Service, an arm of the U.S. Interior Department that oversees offshore drilling. The plan stated that it was "unlikely that an accidental surface or subsurface oil spill would occur from the proposed activities" and that "due to the distance to shore (48 miles (77 km)) and the response capabilities that would be implemented, no significant adverse impacts are expected".[51]
After concluding that a massive oil spill was unlikely, the Interior Department exempted BP's Gulf of Mexico drilling operation from a detailed environmental impact analysis last year. The decision by the department's Minerals Management Service to give BP's lease at Deepwater Horizon a "categorical exclusion" from the National Environmental Policy Act (NEPA) on April 6, 2009