Comparison of several aspects of surface and underground methods of mining for large-scale oil shale extraction in the Piceance Creek Basin suggests that surface mining techniques may have several advantages over underground methods. For a production level of one million barrels of shale oil per day, potential advantages include those related to economics, environmental effects, and the overall national interest. One million barrels of shale oil per day could be produced from 2-3 large surface mines compared to perhaps 10-20 large underground mines. Fewer surface mines would result in: (1) fewer roads and utility corridors, (2) less acres disturbed per barrel of oil pro duced, (3) reduced detrimental effects on ground water and surface water, (4) less wildlife distur bance, (5) a safer overall operation, (6) a greater opportunity to achieve stable long-term land and water reclamation, (7) potential economic advantages related to scale and materials handling, and (8) a three- to five-fold increase in resource recovery. Advantages to underground (including modified in situ [MIS]) mines include: (1) more flexibility of mine siting, (2) mining and handling a minimum of waste rock, and (3) simplified ore grade control for processing.
