A person who holds a valid lease or permit in effect on December 2, 1980, for a cabin, homesite or similar structure not subject to the provisions of §§ 13.146-13 .149 of this subpart, on Federal lands in a park area, may continue the use authorized by that lease or permit, subject to the conditions in §§ 13.138-13 .142.
36 C.F.R. §13.136