60 STAT.] 79TH CONG., 2 1 SESS.-CH. 916-AUG. 8, 1946 ever determined and certified by the Secretary of the Interior to be necessary or advisable in the public interest. The Secretary is there- unto authorized, in his discretion, with the consent of the holders of leases involved, to establish, alter, change, or revoke drilling, pro- ducing, rental, minimum royalty, and royalty requirements of such leases and to make such regulations with reference to such leases, with like consent on the part of the lessees, in connection with the institu- tion and operation of any such cooperative or unit plan as he may deem necessary or proper to secure the proper protection of the public interest. The Secretary may provide that oil and gas leases hereafter issued under this Act shall contain a provision requiring the lessee to operate under such a reasonable cooperative or unit plan, and he may prescribe such a plan under which such lessee shall operate, which shall adequately protect the rights of all parties in interest, including the United States. "Any plan authorized by the preceding paragraph, which includes lands owned by the United States, may, in the discretion of the Secre- tary, contain a provision whereby authority is vested in the Secretary of the Interior, or any such person, committee, or State or Federal officer or agency as may be designated in the plan, to alter or modify from time to time the rate of prospecting and development and the quantity and rate of production under such plan. All leases operated under any such plan approved or prescribed by the Secretary shall be excepted in determining holdings or control under the provisions of any section of this Act. 'When separate tracts cannot be independently developed and operated in conformity with an established well-spacing or develop- ment program, any lease, or a portion thereof, may be pooled with other lands, whether or not owned by the United States, under a com- munitization or drilling agreement providing for an apportionment of production or royalties among the separate tracts of land comprising the drilling or spacing unit when determined by the Secretary of the Interior to be in the public interest, and operations or production pursuant to such an agreement shall be deemed to be operations or production as to each such lease committed thereto. "Any lease issued for a term of twenty years, or any renewal thereof, or any portion of such lease that has become the subject of a cooperative or unit plan of development or operation of a pool, field, or like area, which plan has the approval of the Secretary of the Interior, shall continue in force until the termination of such plan. Any other lease issued under any section of this Act which is com- mitted to any such plan that contains a general provision for alloca- tion of oil or gas shall continue in force and effect as to the land com- mitted so long as the lease remains subject to the plan, provided oil or gas is discovered under the plan prior to the expiration date of the primary term of such lease. The minimum royalty or discovery rental under any lease that has become subject to any cooperative or unit plan of development or operation, or other plan that contains a general provision for allocation of oil or gas, shall be payable only with respect to the lands subject to such lease to which oil or gas shall be allocated under such plan. Any lease which shall be elimi- nated from any such approved or prescribed plan, or from any com- munitization or drilling agreement authorized by this section, and any lease which shall be in effect at the termination of any such approved or prescribed plan, or at the termination of any such communitization or drilling agreement, unless relinquished, shall continue in effect for the original term thereof, but for not less than two years, and so long thereafter as oil or gas is produced in paying quantities. 953 Authority to alter rate of prospeeting, etc. Agreement for ap- portionment of pro- duction or royalties. Continuation d lease Minimum royalty or discovery rental.