The Effects of Lease Size on Yields from Oil Shale Surface Mines

This Note examines the effects of lease size and waste disposal policy on the amount of oil shale that can be recovered from an open pit mine. It also considers process facilities and waste disposal, and assesses the effects of federal leasing policy on the long-term potential of oil shale. The relation between lease size and resource recovery depends on several factors, many of which are sensitive to specific lease conditions. Nonetheless, this study shows that an understanding of that relation can be obtained through geometrical analysis of an open pit mine. The analysis shows that existing regulations limit the amount of recoverable oil shale to no more than 20 percent of the resource in place. Significantly larger yields can be obtained in allowing larger leases or by maintaining existing lease size and allowing off-site disposal of wastes.