or parts of, the Settlement Agreement requiring the signature of the Secretary. (2) Modifications Nothing in this Act precludes the Secretary from approving any modification to exhibits to the Settlement Agreement that is consistent with this Act, to the extent the modification does not otherwise require congressional approval under section 2116 of the Revised Statutes ( 25 U.S.C. 177 ) or other applicable provision of Federal law. (c) Environmental compliance In implementing the Settlement Agreement, the Secretary shall comply with all applicable provisions of— (1) the National Environmental Policy Act of 1969 ( 42 U.S.C. 4321 et seq.)