Tex. Parks & Wild. Code § 23.033

If any of the land described by the drawing entitled "Proposed Guadalupe Mountains National Park, Texas," numbered SA-GM-7100C, dated February, 1965, and on file in the offices of the National Park Service and the Secretary of State of Texas ceases to be used for the Guadalupe Mountains National Park, the state may require a reconveyance, without consideration, of the mineral rights conveyed for the creation of the park.