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NATIONAL REPORTS: UNITED STATES

United States

Uranium exploration and mine development

Historical review

From 1947 through 1970, the United States (US) government fostered a domestic private sector uranium exploration and production industry to procure uranium for military uses and to promote research and development in peaceful atomic energy applications. By late 1957, both the number of new deposits being brought into production by private industry and production capability had increased sufficiently to meet projected requirements. Federal exploration programmes were ended at that time.

Private exploration by the US uranium industry increased throughout the 1970s in response to rising prices and the projected large demand for uranium to fuel an increasing number of nuclear reactors being built or planned for civilian electric power stations. Total annual surface drilling peaked in 1978.

Exploration has been primarily for sandstone-type uranium deposits in districts such as the Grants Mineral Belt and Uravan Mineral Belt of the Colorado Plateau, the Wyoming basins and Texas Gulf Coastal Plain region.

Recent and ongoing uranium exploration and mine development activities

From a recent peak of USD 352.9 million in 2012, US uranium expenditures decreased by 52% to USD 169.9 million in 2016. In 2016, expenditures for uranium surface drilling totalled USD 22.3 million, down USD 6.4 million (22%) from expenditures in 2015 (see table).

Private industry total expenditures for uranium exploration and mine development activities in 2016 were USD 71.9 million, a decrease of more than 31% from 2015 expenditures of USD 104.9 million.

In 2016, expenditures on US uranium production, including facility expenses, were USD 98.0 million, 17% less than the USD 118.5 million spent in 2015. Expenditures for land in 2016 were USD 9.9 million, an 18% decrease from the USD 12.1 million spent in 2015.

The total expenditures for land, exploration, drilling, production and reclamation decreased to USD 169.9 million in 2016, down 24% from USD 223.5 million in 2015. Reclamation expenditures in 2016 were USD 37.2 million, a 37% decrease compared with 2015 expenditures of USD 59.4 million.

The trend of decreasing drilling beginning in 2013 continued in 2016. The number of holes drilled for uranium decreased by 24% from 2015 to 2016, from 1 518 holes to 1 158 holes (see table below). The total metres (m) drilled decreased 14% from 267 614 m in 2015 to 230 734 m in 2016, an 89% decrease from the 2012 peak of 2 181 149 m.

In 2015 and 2016, the US government made no exploration expenditures for uranium domestically or abroad. Data on industry exploration expenses abroad are not available.

The decrease in drilling, production and related expenditures were due in large part to a global oversupply of uranium. Additionally, the ten-year contract between Centrus Energy Corporation and Techsnabexport (TENEX) to supply commercial-origin, Russian low-enriched uranium will replace some of the material previously provided by the Megatons-to-Megawatts programme, which ended in 2013. Deliveries under this contract began in 2013 and, in 2015, the contract term was extended through 2026. According to

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Centrus, the contract was modified to reflect the reduction in global enrichment demand since 2011. The Centrus-TENEX contract maintains the original commitment to purchase 17 million separative work units (SWU) through 2022 and allows delivery deferments through 2026.

United States uranium expenditures, 2006-2016

(USD million)

Notes: Expenditures in nominal USD. Totals may not equal sum of components because of independent rounding. Drilling: All expenditures directly associated with exploration and development drilling.

Production: All expenditures for mining, milling, processing of uranium and facility expense.

Total land and other: All expenditures for: land; geological research; geochemical and geophysical surveys; costs incurred by field personnel in the course of exploration, reclamation and restoration work; and overhead and administrative charges directly associated with supervising and supporting field activities.

Source: US Energy Information Administration, Domestic Uranium Production Report, 2016, Table 8.

United States uranium drilling activities, 2006-2016

Note: Totals may not equal sum of components because of independent rounding.

W = Data withheld to avoid disclosure of individual company data.

Source: US Energy Information Administration, Domestic Uranium Production Report, 2016, Table 1.

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Conventional mine development

No uranium was extracted from underground or surface mines in the United States during 2016 and 2017. The last conventional mining in the United States was completed at Energy Fuels Pinenut mine, a breccia-pipe-type deposit in Arizona, in 2015. Ore from Pinenut is stockpiled at the Energy Fuels Inc. White Mesa Mill. Approximately half of the production from the White Mesa Mill during 2015 and 2016 was from alternate feed material (and half from conventional ore). Alternate feed material is not primary mined uranium, and it is recycled from a number of sources, not all of which originate in the United States. This material includes uranium extracted during municipal water treatment, process residues from uranium conversion, uranium-bearing tails from other metal recovery operations, and others.

A number of small (400-2 000 tU) underground or open-pit mines or properties with some degree of development are on standby status awaiting higher uranium prices throughout the western United States. Properties with more significant resources, including conventional mines on standby status, deposits in development, or significant exploration projects are listed below. Conventional mines previously detailed in the 2016 report are included only if conditions have significantly changed.

Arizona

•Canyon Mine (Energy Fuels): Fully permitted and in development. Development drilling delineated additional high-grade uranium and copper mineralisation that is being evaluated for production of both uranium and copper.

•Anderson (Uranium Energy Corporation): NI 43-101 compliant resource estimate published and preliminary economic assessment completed, but no permitting or development work completed. (NI 43-101 are the Canadian standards of disclosure for mineral projects designed to ensure that misleading, erroneous, or fraudulent information about mineral properties is not published.)

•Los Cuatros (Uranium Energy Corporation): NI 43-101 compliant resource estimate published, but no economic assessment, permitting, or development work completed.

•Workman Creek (Uranium Energy Corporation): NI 43-101 compliant resource estimate published and historic feasibility study completed, but no recent development work completed.

Colorado

•Hansen/Taylor – Tallahassee Creek (Western Uranium): Historic resource with a feasibility study and permitting in process. Western Uranium is attempting to permit mining by Laser Ablation, which complicates the process because neither the state of Colorado nor the US Nuclear Regulatory Commission (NRC) has determined whether this type of mining is in situ milling (such as ISL mining) or mining. Different permits are required for mining and milling.

New Mexico

•Mt. Taylor (General Atomics/Rio Grande Resources): Fully permitted and developed. This mine has been on standby status since 1989.

•Churchrock/Crownpoint (Laramide Resources): NI 43-101 compliant resource estimate published and preliminary economic assessment completed, but no permitting or development work completed.

•Crownpoint/Hosta Butte (enCore Energy): Still in exploration stage.

•LaJara Mesa (Laramide Resources): NI 43-101 compliant resource estimate published and permitting is being pursued slowly, but no development work has occurred.

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Utah

•Henry Mountains Complex (Energy Fuels): NI 43-101 compliant resource estimate published. The Tony M mine is on standby (fully permitted and developed), but the Bullfrog portion of the project requires permitting.

Virginia

•Coles Hill deposit (Virginia Uranium): This is the largest undeveloped uranium deposit in the United States. A feasibility study has been completed, but development cannot proceed until a state moratorium on uranium mining is lifted.

Wyoming

•Sheep Mountain (Energy Fuels): NI 43-101 compliant resource estimate published, a pre-feasibility study has been completed, and permitting is at an advanced stage.

ISL mine development

At the end of 2016, six US uranium ISL plants were operating with a combined capacity of 12.2 million pounds U3O8 per year (Crow Butte Operation in Nebraska and Lost Creek Project, Nichols Ranch ISL Project, Ross Central processing Plant, Smith Ranch-Highland Operation and Willow Creek Project in Wyoming). Seven other ISL plants are planned in New Mexico, South Dakota, Texas and Wyoming.

Smith Ranch/Highland has been producing uranium since 1988, adding the North Butte satellite deposit to the production stream in 2015. Crow Butte has been producing uranium since 1991. Production at Crowe Butte has been dropping since 2013 as the resources are depleted. At both mines, satellite properties were in the process of permitting to continue production from the central processing plants, including the Gas Hills/Peach, Ruby Ranch, North Butte and Brown Ranch projects at Smith Ranch; and North Trend, Marsland and Three Crow projects at Crowe Butte. However, in April 2016, Cameco announced that it would defer wellfield development at Smith Ranch and Crowe Butte and was interested in divesting its US assets. The company will continue to operate existing facilities and restore depleted wellfields.

Energy Fuels Inc. purchased the Nichols Ranch mine from Uranerz in 2015, and in 2016 completed construction of the processing facility, so resins could be processed on-site rather than at the Smith Ranch mine. Energy Fuels has completed permitting of the Hank deposit and is in the process of permitting the Jane Dough deposit, each planned as satellite well fields for the Nichols Ranch mine.

At Lost Creek, actual production exceeded production that was projected from resource estimates. Consequently, the resource estimate for the property was increased by about 30% in 2016. The reason for over production is not yet clear; studies of this phenomenon are focused on the mineralogy of uranium at Lost Creek and details of downhole geophysical surveying. Production at the Lance Mine began in December, 2015 with the first delivery of drummed product in June, 2016. Production fell in late 2016, however, in response to low uranium prices.

The Ross Central Processing Plant (Lance mine) in Wyoming initiated production in 2015. The Hobson/La Palangana and Alta Mesa mines in Texas moved to standby status, in 2016 and 2015, respectively.

There are a number of small (<400 to 2 000 tU) ISL-amenable properties with some degree of development that are on standby status awaiting higher uranium prices in the western United States. Most exploration and development is concentrated in Texas and Wyoming. In addition to permitting of satellite properties adjacent to existing processing plants, other significant ISL properties include those listed below. These deposits either have a significant identified uranium resource (most containing >2 000 tU), and/or are in some stage of feasibility, permitting, or development that indicates they are measurably

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progressing towards production. ISL mines previously detailed in the 2014 report are included only if conditions have significantly changed.

Colorado

•Centennial (Azarga Uranium): preliminary economic assessment completed, permitting in progress. Permitting may be difficult due to the Colorado Mined Land Reclamation Act (2015) requiring every ISL permit application to include proof that five mines have returned all constituents in groundwater to baseline after mining and restoration. To date this documentation for five ISL mines has not been found.

New Mexico

•Churchrock (Laramide Resources): Preliminary feasibility study completed and some permitting completed, but no significant work since 2012.

•Crownpoint, Mancos and Strathmore/Churchrock (Laramide Resources): These three properties all have significant historic resources and are being evaluated by Laramide Resources for mining using ISL technology. However, none have resources that are NI 43-101 compliant, and no recent economic analyses, permitting, or development activities have been initiated.

South Dakota

•Dewey-Burdock, South Dakota (Azarga Uranium): Preliminary economic assessment completed and permitting in progress.

Texas

•Goliad (Uranium Energy Corporation): Fully permitted and development is proceeding slowly.

•Burke Hollow (Uranium Energy Corporation): NI 43-101 compliant resource estimate published, and a feasibility study, permitting, and exploration drilling activities are all in progress.

Wyoming

•Shirley Basin (Ur-Energy): NI 43-101 compliant resource estimate published, a preliminary economic assessment completed, and permitting in progress.

•Lost Soldier (Ur-Energy): NI 43-101 compliant resource estimate published, but no development or permitting activities completed.

•Reno Creek (Energy Fuels & Uranium Energy Corporation): NI 43-101 compliant resource estimate published for most of the deposit (including Pine Tree, Bing and Moore), and a feasibility study and permitting completed for the Reno Creek ore deposit.

•Juniper Ridge (Energy Fuels): NI 43-101 compliant resource estimate published and feasibility study completed, but no permitting activities completed.

Exploration continues for ISL mines in the Wyoming basins, along the Texas Gulf Coast and in the Grants district of New Mexico.

Uranium resources

Identified conventional resources (reasonably assured and inferred resources)

Estimates of reasonably assured resources (RAR) in the United States are not changed from the prior estimates that were reported as of the last edition of the 2016 report.

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At the end of 2016, estimated uranium resources were 17 425 tU at a maximum forward cost of up to USD 80/kgU. At up to USD 130/kgU, estimated resources were 62 890 tU. At up to USD 260/kgU, estimated resources were 138 204 tU.

There have been some changes since the last reporting period for estimated reserves. At the end of 2016, estimated uranium reserves for mines in production were 10 658 tU at a maximum forward cost of up to USD 80/kgU. Estimated reserves for properties with exploration completed, exploration continuing and only assessment work were 15 145 tU at a maximum forward cost of up to USD 80/kgU.

Reserve estimates are available on 70 mines and properties for end of 2015 and on 68 mines and properties for end of 2016. These uranium reserve estimates cannot be compared with the much larger historical data set of uranium reserves that was published in the July 2010 US Department of Energy (DOE) report, US Uranium Reserves Estimates. Those estimates were made by the US Energy Information Administration (US EIA) based on data collected by US EIA and data developed by the National Uranium Resource Evaluation (NURE) programme, operated out of Grand Junction, Colorado, by DOE and predecessor organisations. The US EIA data covered approximately 200 uranium properties, with reserve estimates collected from 1984 through 2002. The NURE data covered approximately 800 uranium properties with reserve estimates, developed from 1974 through 1983. Although the 2014 data collected on the Form EIA-851A survey, Domestic Uranium Report (Annual), cover a much smaller set of properties than the earlier US EIA and NURE data, US EIA believes that, within its scope, the EIA-851A survey data provide more reliable estimates of the uranium recoverable at the specified forward cost than estimates derived from 1974 through 2002. In particular, this is because the NURE data have not been comprehensively updated in many years and are therefore no longer considered a current data source.

The United States has not historically reported inferred resources. In 2014, the United States began an evaluation of the relative importance of the inferred resource category available in published estimates of US uranium properties. Based on this limited analysis, it is estimated that minimal uranium resources for the United States would be increased by 10%, if inferred resources were tabulated in addition to RAR. In recognition of the importance of this class of resource, mechanisms for collecting inferred uranium resource data for the United States are being considered.

Undiscovered conventional resources (prognosticated and speculative resources)

Prognosticated and speculative uranium resources for the United States were last comprehensively assessed in 1980. Records of these estimates are no longer available; therefore they are no longer reported for the United States. The US Geological Survey (USGS) is now re-estimating undiscovered resources for the United States. Estimates for different regions and deposit types have been prioritised, and will be completed in an ongoing fashion. The first of the new undiscovered estimates, for sandstone-hosted rolltype deposits in the Texas Coastal Plain, was completed in 2015. A comprehensive deposit model paper developed as part of the assessment was published in 2016. The USGS undiscovered resource estimate methodology produces probabilistic estimates of potential resources, but not their associated cost categories. The Texas assessment calculated recoverable resources and conversion to in situ resources will require significant conjecture. USGS is now in the process of estimating the undiscovered resources of surficial calcrete-type uranium deposits in the Southern High Plains region of Texas and New Mexico. Historic records of the Kerr-McGee Corporation identified two calcrete-type uranium deposits in northern Texas that have historic resource estimates. These deposits were visited in 2016, and samples collected to help in the development of a deposit model for the region. In other work, a deposit model is in development for the Coles Hill Deposit in Virginia as part of an evaluation of undiscovered resources in the southeast United States.

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Unconventional resources and other materials

Phos Energy Ltd and Cameco Corporation have developed the “PhosEnergy” process to extract uranium from the processing stream at operating phosphate mines. A demonstration plant was tested at a phosphate fertiliser production site in Florida in 2015 with good results, and a pre-feasibility study was completed for a relatively small facility (< 150 tU/yr), and returned operating costs in the lower quartile of USD 50/kgU. The construction of a commercial model awaits favourable economic conditions.

Uranium production

Historical review

Following passage of the Atomic Energy Act of 1946 (AEA), designed to meet US government uranium procurement needs, the Atomic Energy Commission (AEC) from 1947 through 1970 fostered development of a domestic uranium industry (chiefly in the western United States) through incentive programmes for exploration, development and production. To assure that the supply of uranium ore would be sufficient to meet future needs, the AEC in April 1948 announced a domestic ore procurement programme designed to stimulate prospecting and build a domestic uranium mining industry. The AEC also negotiated concentrate procurement contracts, pursuant to the AEA, as amended in 1954, with guaranteed prices for source materials delivered within specified times. Contracts were structured to allow milling companies that built and operated mills the opportunity to amortise plant costs during their procurement-contract period. By 1961, a total of 27 mills were being operated. Overall, 32 conventional mills and several pilot plants, concentrators, up graders, heap leach and solution-mining facilities were operated at various times. The AEC, as the sole government purchasing agent, provided the only US market for uranium. While many of the mills were closed soon after completing deliveries scheduled under AEC purchase contracts, several mills continued to produce concentrate for the commercial market after fulfilling their AEC commitments.

The AEA, as amended, legalised the private ownership of nuclear reactors for commercial electricity generation. By late 1957, domestic ore reserves and milling capacity were sufficient to meet government needs. In 1958, the AEC’s procurement programmes were reduced in scope and, in order to foster utilisation of atomic energy for peaceful purposes, domestic producers of ore and concentrate were allowed to sell uranium to private domestic and foreign buyers. The first US commercial-market contract was finalised in 1966. The AEC announced in 1962 a “stretch out” of its procurement programme that committed the government to take only set annual quantities of uranium for 1967 through 1970. This also assisted in sustaining a viable domestic uranium industry. The US government’s natural uranium procurement programme ended in 1970 and the industry became a private sector, commercial enterprise with no government purchases; however, the government continues to monitor private industry exploration and development activities to meet federal information and data needs.

Exploration by the US uranium industry increased through the 1970s in response to rising prices and the projected large demand for uranium to fuel an increasing number of commercial nuclear power plants that were under construction or planned. US production peaked in 1980 (16 809 tU), after which the industry experienced generally declining production from 1981 to 2003. Beginning in 2004, production began increasing again in response to higher uranium prices. Production began decreasing in 2013 in response to an oversupply of uranium on the world market and consequent lower uranium prices. The oversupply was the result of reactor shutdowns in Germany and Japan following the accident at Fukushima Daiichi. Since 1991, production from ISL mining has dominated US annual production.

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Status of production facilities, production capability, recent and ongoing activities and other issues

US uranium mines produced 1 427 tU in 2015, 24% less than in 2014. In 2016, US uranium mines produced 979 tU, 31% less than in 2015. Total production of US uranium concentrate in 2016 was 1 121 tU, 13% less than in 2015, from nine facilities: one mill in Utah (White Mesa Mill) and eight ISL plants. The eight ISL plants are located in Nebraska, Texas and Wyoming. Uranium ore from underground mines is stockpiled and shipped to the White Mesa Mill for milling into uranium oxide (U3O8) concentrate (yellowcake).

Total shipments of uranium concentrate from US mill and ISL plants were 1 161 tU in 2016, 25% less than in 2015. US producers sold 1 035 tU of uranium concentrate in 2016, 26% less than in 2015.

Uranium production centre technical details

(as of 31 December 2016)

1. US Energy Information Administration, Domestic Uranium Production Report, 2016, Tables 4 and 5. NA = Not available. W = Data withheld to avoid disclosure of individual company data.

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Uranium production centre technical details (cont’d)

(as of 31 December 2016)

1. US Energy Information Administration, Domestic Uranium Production Report, 2016, Tables 4 and 5. NA = Not available. W = Data withheld to avoid disclosure of individual company data.

At the end of 2016, one uranium mill (White Mesa in Utah) was operating with a capacity of 1 538 tonnes of ore per day. Two mills (Shootaring Canyon in Utah and Sweetwater in Wyoming) were on standby status with a combined capacity of 2 884 tonnes of ore per day. Both the Sweetwater and Shootaring Canyon mills have been on standby status since the early 1980s and will require rehabilitation. After acquiring the mill in 2015, Anfield Resources Inc. submitted a plan in 2016 to the Utah Division of Waste Management and Radiation Control to renew its Shootaring Canyon mill’s operating licence. The Piñon Ridge mill in Colorado is planned and fully licensed for Colorado, but construction has not begun. The NRC received letters of intent for mill licence applications from Uranium Resources Inc. (Juan Tafoya mine area, New Mexico) and General Atomics (Mt. Taylor Mine area, New Mexico), however both of these licensing actions have been delayed by the applicant.

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Seven ISL mines were operating in 2016 with a combined capacity of 5 465 tU per year (Crow Butte Operation, Hobson ISL Plant/La Palangana, Lost Creek Project, Nichols Ranch ISL Project, Ross Central Processing Plant, Smith Ranch-Highland Operation and Willow Creek Project). Smith Ranch, Crow Butte and Willow Creek processed lixiviant at the mine site.

Ownership structure of the uranium industry

Ownership of uranium facilities that produced uranium in 2015 and 2016 are public and privately held firms with both foreign and domestic participation. Declining uranium prices have led to some consolidation and shifting in the ownership of US uranium production and processing facilities. EnCore Energy Corp. acquired properties from Energy Fuels, including the Marquez/Nose Rock deposit in New Mexico, the Moonshine deposit in Arizona and the White Canyon District in Utah. Western Uranium merged with Black Range Minerals, adding the Hansen and Taylor deposits, and acquired properties on the Colorado Plateau, including the Sunday Complex, from Energy Fuels Inc. URI is negotiating the sale of its US assets to Laramide Resources.

Employment in the uranium industry

Employment in the raw materials sector (exploration, mining, milling and processing) of the US uranium industry generally declined from 1998 to 2003, and then steadily increased from 2004 to 2008. Employment levels in 2009 showed the first significant decrease over the preceding five years, but from 2009 through 2012 there were marginal gains in total employment. Since 2012, however, employment has declined with the decrease in production. In 2016, total employment in the US uranium production industry was 560 person-years, a decrease of 10% from the 2015 total of 625 person-years at the lowest since 2004. Exploration employment in 2016 was 38 person-years, a 34% decrease compared with 2015. Milling and processing employment data are withheld for 2015 and 2016. Uranium mining employment in 2016 was 255 person-years, 2% more than in 2015. Reclamation employment decreased 16% from 116 person-years in 2015 to 98 person-years in 2016. Uranium production industry employment in 2016 was in nine states: Arizona, Colorado, Nebraska, New Mexico, Oregon, Texas, Utah, Washington and Wyoming.

Future production centres

There are a number of future production centres that are currently in either the permitting or licensing process or under development. Fully permitted centres are listed in the table below, and other developing centres are described in the previous sections on conventional and ISL mine development.

Secondary sources of uranium

Production and/or use of mixed oxide fuels

In 1999, DOE issued a final environmental impact statement and record of decision to make 34 tonnes of surplus weapons-usable plutonium available as mixed oxide (MOX) fuel for use in commercial nuclear reactors.

On April 29, 2015, DOE and Tennessee Valley Authority (TVA) issued the Final Surplus Plutonium Disposition Supplemental Environmental Impact Statement. This work supports international nuclear non-proliferation agreements pursuant to which the United States and Russia will decommission 68 tonnes of surplus plutonium. Following completion of the Mixed Oxide Fuel Fabrication Facility at the DOE Savannah River site in South Carolina, mixed oxide (MOX) fuel will be fabricated for commercial reactors using surplus military plutonium. In February 2011, the TVA and Areva signed a letter of intent