Amendment allows the President to designate any national monument up to 50,000 acres in size; provides that if the President wants to designate a national monument over 50,000 acres, he must submit the proposal to the Governor of the affected State 30 days prior to the proclamation; and after the 30-day period, the monument is created. However, after 2 years, the monument designation will sunset unless Congress has passed a joint resolution approving the President's action.