Uranium Industry Annual 2000 on U.S. uranium activities

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Glossary

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Contract-specified price:: The delivery price determined when a contract is signed. It can be a fixed price or a base price escalated according to a given formula.
Conventional mill (uranium):: A facility engineered and built principally for processing of uraniferous ore materials mined from the earth and the recovery, by chemical treatment in the mill’s circuits, of uranium and/or other valued coproduct components from the processed ore.
Cost model for undiscovered resources:: A computerized algorithm that uses the uranium endowment estimated for a given geological area and selected industry economic indexes to develop random variables that describe the undiscovered resources ultimately expected to be discovered in that area at chosen forward-cost categories.
Cutoff grade:: The lowest grade, in percent U₃O₈, of uranium ore at a minimum specified thickness that can be mined at specified cost.
Development drilling:: Drilling done to determine more precisely size, grade, and configuration of an ore deposit subsequent to the time the determination is made that the deposit can be commercially developed.
Domestic:: Domestic means within the 50 States, District of Columbia, Puerto Rico, the Virgin Islands, Guam, and other U.S. Possessions. The word “domestic” is used also in conjunction with data and information that are compiled to characterize a particular segment or aspect of the uranium industry in the United States.
Domestic purchase:: A uranium purchase from a firm located in the United States.
Domestic sale:: A uranium sale to a firm located in the United States.
Domestic uranium industry:: Collectively, those businesses (whether U.S. or foreign-based) that operate under the laws and regulations pertaining to the conduct of commerce within the United States and its territories and possessions and that engage in activities within the United States, its territories, and possessions specifically directed toward uranium exploration, development, mining, and milling; marketing of uranium materials; enrichment; fabrication; or acquisition and management of uranium materials for use in commercial nuclear power plants.
Enriched uranium:: Uranium in which the ²³⁵U isotope concentration has been increased to greater than the 0.711 percent ²³⁵U (by weight) present in natural uranium.
Enrichment feed deliveries:: Uranium that is shipped under contract to a supplier of enrichment services for use in preparing enriched uranium product to a specified ²³⁵U concentration and that ultimately will be used as fuel in a nuclear reactor.
Enrichment services:: (See Separative Work Units).
Exploration drilling:: Drilling done in search of new mineral deposits, on extensions of known ore deposits, or at the location of a discovery up to the time when the company decides that sufficient ore reserves are present to justify commercial exploitation. Assessment drilling is reported as exploration drilling.
Fabricated fuel:: Fuel assemblies composed of an array of fuel rods loaded with pellets of enriched uranium dioxide.
Foreign purchase:: A uranium purchase of foreign-origin uranium from a firm located outside of the United States.
Foreign sale:: A uranium sale to a firm located outside the United States.
Forward costs (uranium):: The operating and capital costs that will be incurred in any future production of uranium from in-place reserves. Included are costs for labor, materials, power and fuel, royalties, payroll taxes, insurance, and general and administrative costs that are dependent upon the quantity of production and, thus, applicable as variable costs of production. Excluded from forward costs are prior expenditures, if any, incurred for property acquisition, exploration, mine development, and mill construction, as well as income taxes, profit, and the cost of money. Note: By use of forward costing, estimates of reserves for ore deposits in differing geological settings can be aggregated and reported as the maximum amount that can theoretically be extracted to recover the specified costs of uranium oxide production under the listed forward cost categories.
Heap leach solutions:: The separation, or dissolving-out, from mined rock of the soluble uranium constituents by the natural action of percolating a prepared chemical solution through mounded (heaped) rock material. The mounded material usually contains low grade mineralized material and/or waste rock produced from openpit or underground mines. The solutions are collected after percolation is completed and processed to recover the valued components.
In Situ Leach mining (ISL):: The recovery, by chemical leaching, of the valuable components of an orebody without physical extraction of the ore from the ground. Also referred to as “solution mining.”
Long-term contract:: One or more deliveries to occur after a year following contract execution.
Milling of uranium:: The processing of uranium from ore mined by conventional methods, such as underground or openpit, to separate the uranium from the undesired material in the ore.
National Uranium Resource Evaluation (NURE):: A program begun by the U.S. Atomic Energy Commission (AEC) in 1974 to make a comprehensive evaluation of U.S. uranium resources and continued through 1983 by the AEC's successor agencies, the Energy Research and Development Administration (ERDA) and the Depart-ment of Energy (DOE). The NURE program included aerial radiometric and magnetic surveys, hydrogeochemical and stream sediment surveys, geologic drilling in selected areas, geophysical logging of selected boreholes, and geologic studies to identify and evaluate geologic environments favorable for uranium.
Nonconventional plant (uranium):: A facility engineered and built principally for processing of uraniferous solutions that are produced during in situ leach mining, from heap leaching, or in the manufacture of other commodities, and the recovery, by chemical treatment in the plant’s circuits, of uranium from the processed solutions.
Nuclear electric power (nuclear power):: Electricity generated by an electric power plant whose turbines are driven by steam produced by the heat from the fission of nuclear fuel in a reactor.
Nuclear reactor:: An apparatus in which a nuclear fission chain reaction can be initiated, controlled, and sustained at a specific rate. A reactor includes fuel (fissionable material), moderating material to control the rate of fission, a heavy-walled pressure vessel to house reactor components, shielding to protect personnel, a system to conduct heat away from the reactor, and instrumentation for monitoring and controlling the reactor’s systems.
Optional delivery commitment:: A provision to allow the conditional purchase or sale of a specific quantity of material in addition to the firm quantity in the contract.
Person Year:: One whole year, or fraction thereof, worked by an employee, including contracted manpower. It is expressed as a quotient (to two decimal places) of the time units worked during a year (hours, weeks, or months) divided by the like total time units in a year. For example: 80 hours worked is 0.04 (rounded) of a person year; 8 weeks worked is 0.15 (rounded) of a person year; 12 months worked is 1.0 person year. Contracted manpower includes survey crews, drilling crews, consultants, and other persons who worked under contract to support your firm’s ongoing operations.
Processing of uranium:: Uranium-recovery operations at a mill, in-situ leach plant, byproduct plant, or other type of recovery operation.
Reclamation:: Process of restoring surface environment to acceptable pre-existing conditions. Includes surface contouring, equipment removal, well plugging, revegetation, etc.
Reserve Cost Categories of $15, $30, $50, and $100 per Pound U₃O₈:: Classification of uranium reserves estimated by using break-even cutoff grades that are calculated based on forward-operating costs of less than $15, $30, $50, and $100 per pound U₃O₈.
Restoration:: The returning of all affected groundwater to its premining quality for its premining use by employing the best practical technology.

Separative Work Units (SWU):; The standard measure of enrichment services. The effort expended in separating a mass F of feed of assay xf into a mass P of product assay xp and waste of mass W and assay xw is expressed in terms of the number of separative work units needed, given by the expression SWU = WV(x_w) + PV(x_p) - FV(x_f), where V(x) is the "value function," defined as V(x) = (1 - 2x) ln((1 - x)/x).
Spot contract:: A one-time delivery of the entire contract to occur within one year of contract execution.
Spot market:: Buying and selling of uranium for immediate or very near-term delivery. It typically involves transactions for delivery of up to 500,000 pounds U₃O₈ within a year of contract execution.
Spot-market price:: A transaction price concluded “on the spot,” that is, on a one-time, prompt basis. The transaction usually involves only one specific quantity of product. This contrasts with a term-contract sale price, which obligates the seller to deliver a product at an agreed frequency and price over an extended period.
Unfilled requirements:: Requirements not covered by usage of inventory or supply contracts in existence as of January 1 of the survey year.
Uranium:: A heavy, naturally radioactive, metallic element (atomic number 92). Its two principally occurring isotopes are ²³⁵U and ²³⁸U. The isotope ²³⁵U is indispensable to the nuclearindustry because it is the only isotope existing in nature to any appreciable extent that is fissionable by thermal neutrons. The isotope ²³⁸U is also important because it absorbs neutrons to produce a radioactive isotope that subsequently decays to the isotope ²³⁹Pu, which also is fissionable by thermal neutrons.
Uranium concentrate:: A yellow or brown powder obtained by the milling of uranium ore, processing of in situ leach mining solutions, or as a byproduct of phosphoric acid production.
Uranium deposit:: A discrete concentration of uranium mineralization that is of possible economic interest.
Uranium endowment:: The uranium that is estimated to occur in rock with a grade of at least 0.01 percent U₃O₈. The estimate of the uranium endowment is made before consideration of economic availability and any associated uranium resources.
Uranium hexafluoride (UF₆):: A white solid obtained by chemical treatment of U₃O₈ and which forms a vapor at temperatures above 56 degrees Centigrade. UF₆ is the form of uranium required for the enrichment process.
Uranium ore:: Rock containing uranium mineralization in concentrations that can be mined economically, (typically 1 to 4 pounds of U₃O₈ per ton or 0.05 to 0.20 percent U₃O₈).
Uranium oxide:: Uranium concentrate or yellowcake. Abbreviated as U₃O₈.
Uranium property:: A specific tract of land with known uranium reserves that could be developed for mining.
Uranium reserves:: Estimated quantities of uranium in known mineral deposits of such size, grade, and configuration that the uranium could be recovered at or below a specified production cost with currently proven mining and processing technology and under current law and regulations. Reserves are based on direct radiometric and chemical measurements of drill hole and other types of sampling of the deposits. Mineral grades and thickness, spatial relationships, depths below the surface, mining and reclamation methods, distances to milling facilities, and amenability of ores to processing are considered in the evaluation. The amounts of uranium in ore that could be exploited within the chosen forward-cost levels are estimated utilizing available sampling, engineering, geologic, and economic data in accordance with conventional engineering practices.
Uranium resources categories:: Three categories of uranium resources are used to reflect differing levels of confidence in the resources reported. Reasonably assured resources (RAR), estimated additional resources (EAR), and speculative resources (SR) are described below.
Reasonably assured resources (RAR): The uranium that occurs in known mineral deposits of such size, grade, and configuration that it could be recovered within the given production cost ranges, with currently proven mining and processing technology. Estimates of tonnage and grade are based on specific sample data and measurements of the deposits and on knowledge of deposit characteristics. RAR correspond to DOE's uranium reserves category.

Estimated additional resources (EAR): The uranium in addition to RAR that is expected to occur, mostly on the basis of direct geological evidence, in extensions of well-explored deposits, little explored deposits, and undiscovered deposits believed to exist along well-defined geological trends with known deposits, such that the uranium can subsequently be recovered within the given cost ranges. Estimates of tonnage and grade are based on available sampling data and on knowledge of the deposit characteristics, as determined in the best-known parts of the deposit or in similar deposits. EAR correspond to DOE's probable potential resources category.

Speculative resources (SR): Uranium in addition to EAR that is thought to exist, mostly on the basis of indirect evidence and geological extrapolations, in deposits discoverable with existing exploration techniques. The locations of deposits in this category can generally be specified only as being somewhere within given regions or geological trends. The estimates in this category are less reliable than estimates of RAR and EAR. The category of SR corresponds to DOE's possible potential resources plus speculative potential resources categories combined.
Usage Agreement:: Contracts held by enrichment customers that allow feed material to be stored at the enrichment plant site in advance of need.
Yellowcake:: A natural uranium concentrate that takes its name from its color and texture. Yellowcake typically contains 70 to 90 percent U₃O₈ by weight. It is used as feedstock for uranium fuel enrichment and fuel pellet fabrication.(See uranium oxide).

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