S.D. Codified Laws § 5-7-23
The term of all such oil and gas leases shall be for a period not to exceed ten years and as long thereafter as oil or gas is produced from the leased land. In no event, however, shall such leases covering lands granted to the state of South Dakota by the Enabling Act of February 22, 1889, or by later congressional act, be for terms longer than as provided in said acts as subsequently amended or to be amended. If for any reason production of oil or gas from the leased lands shall cease after the primary term the lessee shall be entitled to resume drilling operations on said land within such reasonable time as may be prescribed by the rules and regulations of the commissioner of school and public lands, and if such drilling operations shall be conducted with reasonable diligence and the production of oil and gas in paying quantities shall result therefrom, then said lease shall remain in force as long thereafter as oil or gas in paying quantities is or can be produced from the leased lands.
SDCL 5-7-23