The U.S. Department of Transportation (Department) is seeking public comment on this proposed update to its National Environmental Policy Act (NEPA) implementing procedures, DOT Order 5610.1D, Procedures for Considering Environmental Impacts. The Department is proposing this update and seeking public review and comment on the proposal, consistent with the Council on Environmental Quality's regulations implementing NEPA. The document was published in the Federal Register on December 20, 2016, and comments may be made now to docket number DOT-OST-2016-0239. The comment period will end 21 days from the date of publication. For more information, see the Federal Register Notice and the Department's existing NEPA implementing procedures, DOT Order 5610.1, and administrative record regarding the proposed new categorical exclusions.