43 CFR 3927.50: Diligent development.

Oil shale lessees must meet:

(a) Diligent development milestones;

(b) Annual minimum production requirements or payments in lieu of production starting the 10th lease year, except when the BLM determines that operations under the lease are interrupted by strikes, the elements, or causes not attributable to the lessee. Market conditions are not considered a valid reason to waive or suspend the requirements for annual minimum production. The BLM will determine the annual production requirements based on the extraction technology to be used and on the BLM's estimate of the recoverable resources on the lease, expected life of the operation, and other factors.