assurances that all relevant documents concerning the proposed exchange or purchase for which such authority is proposed to be exercised (including documents related to compliance with the National Environmental Policy Act of 1969 [
42 U.S.C. 4321 et seq.] and all other applicable provisions of law) are available for public inspection in the office of the Secretary concerned located nearest to the lands proposed for transfer out of Federal ownership in furtherance of such exchange and that the relevant portions of such documents are also available in the offices of the Secretary concerned in Washington, District of Columbia; and