An Indian tribe may assume all or any part of the functions of a State Historic Preservation Officer in accordance with sections 302302 and 302303 of this title, with respect to tribal land, as those responsibilities may be modified for tribal programs through regulations issued by the Secretary, if—

(1) the Indian tribe's chief governing authority so requests;

(2) the Indian tribe designates a tribal preservation official to administer the tribal historic preservation program, through appointment by the Indian tribe's chief governing authority or as a tribal ordinance may otherwise provide;

(3) the tribal preservation official provides the Secretary with a plan describing how the functions the tribal preservation official proposes to assume will be carried out;

(4) the Secretary determines, after consulting with the Indian tribe, the appropriate State Historic Preservation Officer, the Council (if the Indian tribe proposes to assume the functions of the State Historic Preservation Officer with respect to review of undertakings under section 306108 of this title), and other Indian tribes, if any, whose tribal or aboriginal land may be affected by conduct of the tribal preservation program, that—

(A) the tribal preservation program is fully capable of carrying out the functions specified in the plan provided under paragraph (3);

(B) the plan defines the remaining responsibilities of the Secretary and the State Historic Preservation Officer; and

(C) the plan provides, with respect to properties neither owned by a member of the Indian tribe nor held in trust by the Secretary for the benefit of the Indian tribe, at the request of the owner of the properties, that the State Historic Preservation Officer, in addition to the tribal preservation official, may exercise the historic preservation responsibilities in accordance with sections 302302 and 302303 of this title; and

(5) based on satisfaction of the conditions stated in paragraphs (1), (2), (3), and (4), the Secretary approves the plan.