As used in this part, the term:

(a) Act means the Department of the Interior Appropriations Act, Fiscal Year 1981 (Pub. L. 96-514).

(b) Bureau means the Bureau of Land Management.

(c) Constructive operations means the exploring, testing, surveying or otherwise investigating the potential of a lease for oil and gas or the actual drilling or preparation for drilling of wells therefor.

(d) NPR-A means the area formerly within Naval Petroleum Reserve Numbered 4 Alaska which was redesignated as the National Petroleum Reserve—Alaska by the Naval Petroleum Reserves Production Act of 1976 (42 U.S.C. 6501).

(e) Reworking operations means all operations designed to secure, restore or improve production through some use of a hole previously drilled, including, but not limited to, mechanical or chemical treatment of any horizon, deepening to test deeper strata and plugging back to test higher strata.

(f) Special Areas means the Utokok River, the Teshekpuk Lake areas and other areas within NPR—A identified by the Secretary as having significant subsistence, recreational, fish and wildlife or historical or scenic value.

(g) Production allocation methodology means a way of attributing the production of oil and gas produced from a unit well or wells to individual tracts committed to the unit and forming a participating area.

(h) Reservoir heterogeneity means spatial differences in the oil and gas reservoir properties. This can include, but is not limited to, the thickness of the reservoir, the amount of pore space in the reservoir rock that contains oil, gas, or water, and the amount of water contained in the reservoir rock. This information may be used to allocate production.

(i) Variation in reservoir producibility means differences in the rates oil and gas wells produce from the reservoir. These differences can result from variations in the thickness of the reservoir, porosity, and the amount of connected pore space.

[46 FR 55497, Nov. 9, 1981, as amended at 53 FR 17358, May 16, 1988; 73 FR 6442, Feb. 4, 2008]