(a) Subject to valid existing rights, each wilderness area designated under this subchapter shall be administered by the Secretary, through the Director of the Bureau of Land Management, in accordance with the provisions of the Wilderness Act [16 U.S.C. 1131 et seq.] governing areas designated by that Act as wilderness, except that any reference in such provisions to the effective date of the Wilderness Act shall be deemed to be a reference to December 31, 1987.

(b) Within the wilderness areas designated by this subchapter, the grazing of livestock, where established prior to December 31, 1987, shall be permitted to continue subject to such reasonable regulations, policies, and practices as the Secretary deems necessary, as long as such regulations, policies, and practices fully conform with and implement the intent of Congress regarding grazing in such areas as such intent is expressed in the Wilderness Act [16 U.S.C. 1131 et seq.] and section 108 of Public Law 96–560 (16 U.S.C. 1133 note).