; or (B) are otherwise determined by the Secretary to be connected to the history, construction, and legacy of the Transcontinental Railroad. (3) Other governmental and nongovernmental programs of an educational, research, or interpretive nature that are directly related to the history, construction, and legacy of the Transcontinental Railroad. (d) Cooperative agreements and memoranda of understanding To achieve the purposes of this section and to ensure effective coordination of the Federal and non-Federal elements of the Network described in subsection (c) with National Park System units and programs of the National Park Service, the Secretary may enter into cooperative agreements and memoranda of understanding with, and provide technical assistance to, the heads of other Federal agencies, States, units of local government, regional governmental bodies, and private entities. 5. Agreements affecting certain historical crossings (a) Agreements At the request of an adjacent landowner, the Superintendent shall enter into an agreement with the adjacent landowner regarding an existing historical crossing within the Park. (b) Terms of agreement The agreement shall provide that— (1) the adjacent landowner shall give notice to the Superintendent of a proposed activity that will affect the surface or subsurface of the historical crossing; (2) the Superintendent shall review and approve or disapprove the proposed activity within 30 days of the date that the adjacent landowner gives notice of a proposed activity under paragraph (1); (3) the Superintendent shall approve a proposed activity if— (A) the adjacent landowner will restore the surface of the historical crossing within a reasonable time following the completion of the proposed activity; (B) the proposed activity will last less than one month and will have limited physical impact on the surface of the historical crossing; (C) the proposed activity has been implemented by the adjacent landowner or other adjacent landowners in the past