(a) If the Secretary considers that all or part of the agency's decision as outlined under § 78.4(a) is inconsistent with the intent of the Act or these regulations for use of the waiver under extraordinary circumstances, the Secretary shall notify the Agency Head and the Director of the Office of Management and Budget within 5 days of receipt of the Federal Agency notice under § 78.4(a) of termination of the waiver, or make appropriate recommendations for modifications of the waiver's use. Termination of a waiver by the Secretary is final.

(b) If the waiver is still in effect at the time the Federal Agency Head receives recommendations from the Secretary, the Agency Head shall consider the recommendations and any comments received from the Advisory Council and the State Historic Preservation Officer before deciding whether to continue, withdraw, or modify the waiver. The Federal Agency Head shall respond to recommendations received from the Secretary either accepting or rejecting those recommendations, and, where recommendations are rejected, explaining the reasons for such a decision. Information copies of such response shall be forwarded by the Federal Agency Head to the Advisory Council on Historic Preservation and the appropriate State Historic Preservation Officer.

(c) If the waiver is no longer in effect at the time the Federal Agency Head receives recommendations from the Secretary or comments from the Advisory Council or the State Historic Preservation Officer, the Federal Agency Head should consider such recommendations and comments in similar future emergencies.