77-3-421. Duration of lease. (1) All state oil and gas leases entered by the board shall be granted for a primary term of not more than 10 years or less than 5 years and as long thereafter as oil or gas in paying quantities is produced, on condition that all drilling, rental, and other obligations are fully kept and performed by the lessee. However, leases for a period of less than 5 years may be issued if the board determines that such shorter term is necessary to ensure full compensation for the oil and gas resource.

(2) Oil or gas produced from any part of a unit in which state lands are included by virtue of a pooling agreement are considered to be produced from the state lands therein within the meaning of this part.

(3) The board may grant reasonable extensions of the primary term of a state oil or gas lease upon a showing that the lessee, despite due care and diligence, is or has been directly or indirectly prevented from exploring, developing, or operating the lease or is threatened with substantial economic loss, due to litigation regarding the lease or another lease in the immediate area held by the same lessee, state compliance with the Montana Environmental Policy Act, Title 75, chapter 1, parts 1 through 3, rules adopted under Title 75, chapter 1, or adverse conditions caused by natural occurrences.