Oil shale Tract C-b revised detailed development plan

"A new multiphase mining plan for the Cathedral Bluffs Oil Shale Project is presented here for the purpose of revising the Detailed Development Plan (DDP) for Federal Oil Shale Lease Tract C-b. This new plan involves significant changes in the design, layout, and operation of the underground oil shale mine and its integral shale oil recovery system. These and other pertinent features of the plan are covered in detail for review and approval by the Deputy Conservation Manager - Oil Shale"--Page 4.1