Section 3141.5-2 - Term of lease(a) Combined hydrocarbon leases or oil and gas leases shall have a primary term of 10 years and shall remain in effect so long thereafter as oil or gas is produced in paying quantities.(b) Tar Sand leases shall have a primary term of 10 years and shall remain in effect so long thereafter as tar sand is produced in paying quantities.70 FR 58615, Oct. 7, 2005