Section 212.28 - Unitization and communitization agreements, and well spacing(a) For the purpose of promoting conservation and efficient utilization of minerals, the Secretary may approve a cooperative unit, drilling or other development plan on any leased area upon a determination that approval is advisable and in the best interest of the Indian mineral owner. For the purposes of this section, a cooperative unit, drilling or other development plan means an agreement for the development or operation of a specifically designated area as a single unit without regard to separate ownership of the land included in the agreement. Such cooperative agreements include, but are not limited to, unit agreements, communitization agreements and other types of agreements that allocate costs and benefits.(b) The consent of the Indian mineral owner to such unit or cooperative agreement shall not be required unless such consent is specifically required in the lease.(c) Requests for approval of cooperative agreements which comply with the requirements of all applicable rules and regulations shall be filed with the superintendent or area director.(d) All Indian mineral owners of any right, title or interest in the mineral resources to be included in a cooperative agreement must be notified by the lessee at the time the agreement is submitted to the superintendent or area director. An affidavit from the lessee stating that a notice was mailed to each mineral owner of record for whom the superintendent or area director has an address will satisfy this notice requirement.(e) A request for approval of a proposed cooperative agreement, and all documents incident to such agreement, must be filed with the superintendent or area director at least ninety (90) days prior to the first expiration date of any of the Indian leases in the area proposed to be covered by the cooperative agreement.(f) Unless otherwise provided in the cooperative agreement, approval of the agreement commits each lease to the unit in the area covered by the agreement on the date approved by the Secretary or the date of first production, whichever is earlier, as long as the agreement is approved before the lease expiration date.(g) Any lease committed in part to any such cooperative agreement shall be segregated into a separate lease or leases as to the lands committed and lands not committed to the agreement. Segregation shall be effective on the date the agreement is effective.(h) Wells shall be drilled in conformity with a well spacing program approved by the authorized officer.