16 U.S.C. § 79d
The owner of improved property on the date of its acquisition by the Secretary under this subchapter may, as a condition of such acquisition, retain for himself and his heirs and assigns a right of use and occupancy of the improved property for noncommercial residential purposes for a definite term of not more than twenty-five years or, in lieu thereof, for a term ending at the death of the owner or the death of his spouse, whichever is later. The owner shall elect the term to be reserved. Unless the property is wholly or partially donated to the United States, the Secretary shall pay the owner the fair market value of the property on the date of acquisition minus the fair market value on that date of the right retained by the owner. A right retained pursuant to this section shall be subject to termination by the Secretary upon his determination that it is being exercised in a manner inconsistent with the purpose of this subchapter, and it shall terminate by operation of law upon the Secretary's notifying the holder of the right of such determination and tendering to him an amount equal to the fair market value of that portion of the right which remains unexpired.
The term "improved property", as used in this section, means a detached, noncommercial residential dwelling, the construction of which was begun before October 9, 1967, together with so much of the land on which the dwelling is situated, the said land being in the same ownership as the dwelling, as the Secretary shall designate to be reasonably necessary for the enjoyment of the dwelling for the sole purpose of noncommercial residential use, together with any structures accessory to the dwelling which are situated on the land so designated.
The Secretary shall have, with respect to any real property acquired by him in sections 5 and 8, township 13 north, range 1 east, Humboldt meridian, authority to sell or lease the same to the former owner under such conditions and restrictions as will assure that it is not utilized in a manner or for purposes inconsistent with the national park.
16 U.S.C. § 79d