16 U.S.C. § 192b-10
The Secretary of the Interior (hereinafter referred to as the "Secretary") is authorized to acquire, by donation, purchase with donated or appropriated funds, or by exchange, lands or interests therein within the area generally depicted as "Proposed Park Additions" on the map entitled "Proposed Park Additions, Rocky Mountain National Park", numbered 121-80, 106-A and dated May, 1989, which map shall be on file and available for public inspection in the Office of the National Park Service, Department of the Interior. Upon acquisition of such lands, the Secretary shall revise the boundary of Rocky Mountain National Park to include such lands within the park boundary and shall administer such lands as part of the park subject to the laws and regulations applicable thereto.
Upon acquisition of such lands by the Secretary, the Secretary of Agriculture shall revise the boundary of the Roosevelt National Forest to exclude such lands from the national forest boundary.
The Secretary is authorized to enter into an agreement with the owner of the lands identified as Tract 1127 and 1127B4, Section 23, Township 3 North, Range 73, Boulder County, Colorado, within the boundaries of Rocky Mountain National Park, to ensure the right of use as a single family residence, unless said property is being developed or is officially proposed to be developed by the owners in a manner which would substantially change its use.
16 U.S.C. § 192b-10