Quick search by citation:

16 U.S. Code § 410zz–2 - Expansion of boundaries

(a) In general
The boundaries of the park are hereby modified to reflect the addition of approximately 3,460 acres of land and interests therein as generally depicted on the map entitled “Saguaro National Monument Additions” and dated April, 1994.
The boundaries of the park are further modified to include approximately 1,152 acres, as generally depicted on the map titled “Saguaro National Park Proposed Boundary Adjustment”, numbered 151/80,045G, and dated December 2020.
The map referred to in subparagraph (A) shall be on file and available for inspection in the appropriate offices of the National Park Service.
(b) Land acquisition
Within the lands added to the park pursuant to subsection (a), the Secretary is authorized to acquire lands and interests therein by donation, purchase with donated or appropriated funds, transfer, or exchange: Provided, That no such lands or interests therein may be acquired without the consent of the owner thereof unless the Secretary determines that the land is being developed, or is proposed to be developed in a manner which is determental [1] to the integrity of the park.
The Secretary may, with the consent of the State of Arizona and in accordance with Federal and State law, acquire land or interests therein owned by the State of Arizona within the boundary of the park.
If the Secretary is unable to acquire the State land under paragraph (2), the Secretary may enter into an agreement with the State that would allow the National Park Service to manage State land within the boundary of the park.
(c) Withdrawal

Subject to valid existing rights, all Federal lands within the park are hereby withdrawn from all forms of entry, appropriation, or disposal under the public land laws, from location, entry, or patent under the United States mining laws, and from disposition under all laws relating to mineral and geothermal leasing, and mineral materials, and all amendments thereto.

[1]  So in original. Probably should be “detrimental”.
Editorial Notes

2020—Subsec. (a). Pub. L. 116–260, § 201(b)(1), designated existing provisions as par. (1) and added par. (2).

Subsec. (b)(2), (3). Pub. L. 116–260, § 201(b)(2), added pars. (2) and (3) and struck out former par. (2) which read as follows: “Lands or interests therein owned by the State of Arizona or a political subdivision thereof may only be acquired by donation or exchange.”