21-05-08 US onshore federal lands contain an estimated 31 bn barrels of oil and 231 tcf of natural gas, although some 60 % of the lands with the potential for oil and natural gas development are presently closed to leasing, according to an inventory report released by the Bureau of Land Management (BLM).
All told, 62 % of the oil and 41 % of the natural gas are inaccessible for development, BLM said. An additional 30 % of onshore federal oil and 49 % of natural gas "may only be developed subject to restrictions over and above standard environmental lease terms, including seasonal timing limitations," BLM said.

According to the study, in the inventory areas just 8 % of the oil and 10 % of the gas are accessible under standard lease terms.
The 279 mm acres in the inventory are managed by various agencies within the Interior Department and the US Forest Service, which is part of the Agriculture Department. Some of the areas are split estates, where the subsurface mineral resources are owned by the federal government and the surface is privately owned.