US Uranium Mining and Exploration

Uranium mining in the USA today is undertaken by few companies on a relatively small scale. Uranium exploration is undertaken by many companies, often going over areas that were mined in the 1950s-80s. Following the prohibition of uranium imports from Russia (see below), there is a major government-backed push to boost domestic uranium production.

Most US uranium-producing states are 'agreement states' vis a vis the Nuclear Regulatory Commission (NRC) and have authority to issue permits and regulate uranium mining and milling. The NRC's role is then minimal. In February 2015 Wyoming, the major uranium production state, passed legislation to make it an agreement state, along with all the other uranium-producing states. The NRC agreed to this in 2018. Five of the six operating uranium recovery facilities previously under NRC oversight are in Wyoming. Under a 2010 agreement the NRC collaborates with the federal Bureau of Land Management (BLM) on environmental assessment of mine proposals. A majority of US uranium production comes from Wyoming’s Powder River Basin.

However, land access is partly controlled by the US government, and in 2011 the Interior Secretary issued an order banning new hardrock uranium mining in about 4000 square km of land in Arizona for 20 years, which sterilized 145,000 tU of known resources according to the Nuclear Energy Institute (NEI) and also much prospective ground. The industry contends that uranium exploration and mining here would not compromise the Grand Canyon watershed. The land is not within the Grand Canyon National Park or the buffer zone protecting the national park. The industry contends that that the land withdrawal is not justified by information in the Interior Department’s environmental assessment, and is an “arbitrary agency action” under the Administrative Procedure Act, and that it fails to comply with the National Environmental Policy Act by failing to take the “hard look” at the withdrawal’s consequences that the US Supreme Court required in a unanimous 1989 decision.

In March 2013 a US District Court judge declined to overturn the mining ban, and in October 2014 the US District Court affirmed the ban (see Nuclear Energy Institute comment). This was then appealed, and in December 2017 the US Court of Appeals for the Ninth Circuit upheld the earlier decisions.

On 8 August 2023 President Biden designated the Baaj Nwaavjo I’tah Kukveni – Ancestral Footprints of the Grand Canyon National Monument, covering nearly 4000 square km, permanently banning new uranium mining claims in the area and replacing the 20-year moratorium. Existing valid mining claims are not affected. An appeal by the Arizona legislature against the presidential proclamation that created the national monument was dismissed by the US Court of Appeals for the Ninth Circuit in April 2026.

Earlier, in January 2015, the Environment Protection Agency (EPA) proposed new health and environmental protection standards for uranium extraction including tighter groundwater quality and monitoring standards, under the Uranium Mill Tailings Radiation Control Act of 1978. The proposed standards address the increased use of ISL for uranium recovery in the USA. The proposed rule describes how ISL facilities are to characterize groundwater chemistry before commencing uranium mining. The rule would also require compliance with whichever standard is most stringent from the Safe Drinking Water Act, the Resource Conservation and Recovery Act, or the Uranium Mill Tailings Radiation Control Act for each of 13 groundwater constituents: arsenic, barium, cadmium, chromium, lead, mercury, selenium, silver, nitrate, molybdenum, radium, total uranium, and gross alpha particle activity. The final post-mining water quality would need to match the original, and be monitored for 30 years by the operator unless chemistry was satisfactory and stable over three years. The final standards were to be administered by the NRC. However, the EPA withdrew the proposed rule in October 2018 following issues raised in public comments and because the anticipated influx of new ISL licence applications had not materialized.

In May 2024 the Prohibiting Russian Uranium Imports Act was signed into law, banning imports of Russian-origin unirradiated LEU and natural uranium from August 2024, with limited waivers available until January 2028. Russia responded with reciprocal export restrictions in November 2024.

Production

US Uranium Production, tonnes U

Company	ISL operations, hard rock mill	2016	2017	2018	2019	2020	2021	2022	2023	2024	2025
Cameco	Smith Ranch - Highland, WY	358	118	0	0	0	0	8	8	5	9
Cameco	Crow Butte, NE	89	29	0	0	0	0	2	1	2	2
Uranium Energy Corp (UEC)	Willow Creek, WY	23	38	0	0	0	0	0	0	0	37
Ur-Energy	Lost Creek, WY	216 drummed (207 captured)	98 drummed (102 captured)	110 drummed (116 captured)	18	4	0	0	9	96	158
Peninsula/Strata	Lance, WY (Ross unit)	49	44 drummed	55	13	0	0	2	1	1	5
Uranium Energy Corp (UEC)	Hobson - La Palangana, TX	0	0	0	0	0	0	0	0	0	0
EFRC (Uranerz)	Nichols Ranch, WY	129	100	54	27	2	0	0	1	0	0
enCore Energy	Alta Mesa, TX	0	0	0	0	0	0	0	0	64	230
EFRC	White Mesa mill + third party	262	138.5 + 365.5	136 + 163	0	0	0	62	0	61	390
Total		1126	931	564	58	6	8	75	19	260	831

Source: EIA, Domestic Uranium Production Report. Figures are in tonnes U.

Energy Fuels – EFRC

Energy Fuels Resources Corporation (EFRC), a Colorado-based subsidiary of Energy Fuels Inc of Toronto, operates the White Mesa mill in southeastern Utah – the only conventional uranium mill in the USA – and has mines and development projects across Utah, Colorado, Arizona, Wyoming, New Mexico and formerly Texas. The company has diversified into rare earth element (REE) production.

In April 2012 EFRC agreed to take over all Denison Mines' US assets and operations, including the White Mesa mill, in a C$106 million merger, completed in June 2012. Korea Electric Power Co. (KEPCO) was the largest shareholder in both companies. It supported the takeovers and held 9.6% of the expanded EFRC company (as well as retaining equity in Denison). KEPCO’s long-term offtake agreement with Denison Mines was assigned to EFRC as part of the June 2012 takeover of Denison’s US assets. In December 2013 EFRC entered into a strategic relationship with KEPCO as its largest shareholder, focused on development of the Wyoming projects and uranium supply. At the end of 2016 KEPCO equity in EFRC was transferred to KHNP Canada Energy Ltd.  

In August 2013 Energy Fuels took over Strathmore Minerals in a C$29 million deal, adding properties in Wyoming and New Mexico. In June 2015 it completed a $150 million takeover of Uranerz Energy Corp, gaining the Nichols Ranch ISL operation in Wyoming. Its acquisition of Mestena Uranium, a private Texas company with the Alta Mesa ISL plant, was finalized in mid-2016. EFRC subsequently sold Alta Mesa to enCore Energy for $120 million in February 2023.

White Mesa mill

The White Mesa mill, located in southeastern Utah near 'Four Corners', was built in 1980 and refurbished in 2007. It has a versatile licensed capacity of about 3000 tU/yr; EFRC claims overall licensed capacity exceeding 4400 tU/yr and says it could sustain production of roughly half that with improved uranium prices and additional permits.

The mill processes two main types of conventional feed: carnotite in sandstone from the Colorado Plateau, and fine-grained uraninite from Arizona Strip breccia pipes. Some ore is hauled over 1000 km to the mill. An alternate feed circuit handles other uranium-bearing materials – such as remediation wastes and those derived from uranium conversion and other metal processing – which may be very high grade. These materials can be processed separately or blended into the primary leach circuit; the circuit has recovered over 550 tU from such sources since 2005. White Mesa also calcines UO₄ received from the Nichols Ranch ISL operation.

White Mesa also has a vanadium co-product recovery circuit, recommissioned in 2019. EFRC holds an inventory of V₂O₅ and produces when market conditions warrant.

To 2019 the mill had produced over 17,000 tU from 125 different mines and over 20,000 t of vanadium. It accounted for 21% of US uranium production over 2011–15.

In 2020 EFRC arranged to import about 2000 tonnes of uranium-bearing material from Silmet, a rare earths processing plant in Estonia. The material, consisting of tailings from tantalum-niobium recovery, has a uranium grade equivalent to US high-grade ores.

White Mesa produced 1,015,000 lbs U₃O₈ in 2025, exceeding the company’s guidance.

Mining operations: Colorado Plateau – Uravan Mineral Belt (Utah/Colorado Border)

EFRC has several mines in the Uravan Mineral Belt on the Colorado Plateau (straddling the Utah-Colorado border) containing 2100 tU in placer deposits plus vanadium co-product (Uravan = uranium + vanadium). These La Sal Complex mines about 100 km northeast of the White Mesa mill comprise La Sal, Beaver and Pandora which are mature operating mines with extensive interconnected underground workings. The Rim mine is also here.

In October 2012 EFRC said it would place Beaver and La Sal on standby, pending uranium market improvement and would finish mining at Pandora by mid-year due to depleted resources. Production resumed at La Sal and Pandora in December 2023 in the light of stronger market conditions.

Other EFRC Uravan mines operated by EFRC in 2007-08 but then closed include Topaz, West Sunday and Sunday/St. Jude in the Sunday complex in Colorado. There are no plans to bring the other mine there, Van 4, into production. EFRC reopened the refurbished Whirlwind mine (including Packrat and Bonanza) following Bureau of Land Management and state approval, but put it on standby in 2009. It had 425 tU measured and indicated resources and 770 tU inferred resources. These properties were sold to Western Uranium & Vanadium Corp in 2014.

In 2021 Vancouver-based Consolidated Uranium bought the Daneros mine, along with Tony M, Rim, and some Colorado properties. All are close to the White Mesa mill which will treat ore on a toll basis. As part of the purchase deal, EFRC acquired a 19.9% stake in Consolidated Uranium. In June 2023 work began to reopen the Tony M mine in the light of strong market conditions.

Daneros was the main asset of White Canyon Uranium, which Denison bought for $57 million in 2011. It has been mined since December 2009 and ore was trucked 100 km to the White Mesa mill for treatment and recovery of U₃O₈ product. JORC-compliant resource figures of 447 tU in 0.22%U ore were quoted in August 2010, and production was planned to be 227 tU/yr. In October 2012 EFRC put Daneros on standby.

Henry Mountains, Utah

The Henry Mountains deposits in Utah including Tony M, Southwest and Bullfrog have 4900 tU as indicated resources at over 0.2% and inferred resources of 3100 tU, both NI 43-101 compliant. All these are some 120 km west of the White Mesa mill. Denison began production from the Tony M mine in 2007, but late in 2008 put it on care and maintenance. The company was intending to spend $35 million on the adjacent new Bullfrog mine, but it was put on hold in 2008. Tony M was sold to Consolidated Uranium in 2021.

Arizona Strip

Denison held four old mines in the Arizona Strip of north central Arizona, along with some new deposits there, though all these are some 500 km southwest from the White Mesa mill and some may be impacted by the Bureau of Land Management decision to stall developments near the Grand Canyon.

Pinyon Plain (formerly Canyon Mine), originally licensed in 1986 and fully permitted, has 936 tU as measured and indicated resources at 0.75%U (NI 43-101 compliant), with 5400 t copper at average grade 4.93%, increased by drilling undertaken into 2017. Mining commenced in late December 2023, with ore trucked to the White Mesa mill. In 2025 the mine produced ore containing about 1,530,000 lbs U₃O₈ at an average grade of 1.62%, making it one of the highest-grade uranium mines in US history. Remaining reserves are 2.1 million lbs in the Main Zone and 0.5 million lbs in the Juniper Zone. Copper is a potential co-product.

Arizona One underground mine resumed production in 2009 but closed early in 2014 as known resources were depleted.

Pinenut was mined in the 1980s and produced 200 tU then, with a shaft 410 m deep. EFRC brought the mine back into production in 2013 but closed it in mid-2015 pending uranium price improvement.

Wate was acquired in 2015 from Vane Minerals and Anfield Resources. Like Pinenut and Pinyon Plain, it is a high-grade breccia pipe deposit, with NI 43-101 compliant inferred resources of 432 tU at 0.67% U.

Also in Arizona, the EZ mine is subject to land use restrictions by the Bureau of Land Management. It has 810 tU as inferred resources.

Wyoming

Nichols Ranch ISL – Uranerz Energy Corp, which became part of Energy Fuels in mid-2015, received an NRC materials licence for its Nichols Ranch ISL operation in the Powder River Basin of Wyoming in July 2011, with final state approval in October 2012. Production commenced in April 2014. EFRC built its own elution plant, which was commissioned and licensed early in 2016. Nichols Ranch ISL was placed on standby in 2019 and has not resumed production. In 2024 Energy Fuels announced it was working to prepare for its restart.

EFRC has NI 43-101 compliant resources of 6060 tU at about 0.1% U in seven Uranerz deposits, including measured and indicated resources of 1137 tU for Nichols Ranch itself, 860 tU for Hank, and 1100 tU for West North-Butte. The contiguous Jane Dough permit area (1052 tU) was added to the Nichols Ranch project and fully permitted by the NRC in March 2017. It would be followed by Hank as a satellite operation, and the Bureau of Land Management (BLM) issued approval for this in mid-2015. The Uranerz North Reno Creek property east of Nichols Ranch was sold by EFRC to UEC in 2017 for $5.4 million, with 1650 tU measured and indicated resources at 0.048 %U grade.

Sheep Mountain has 11,700 tU measured and indicated resources at 0.1%U, including 7100 probable reserves. Uranium One's 50% interest was bought by Titan Uranium in 2009, then transferred to EFRC via a 2012 merger with Titan. Underground development took place in the 1970s. A prefeasibility study by Titan assessed mining the Congo open pit and underground sections with heap leaching recovery to produce 580 tU/yr. EFRC updated this preliminary feasibility study for the whole project. Development was proposed in conjunction with Gas Hills, 45 km north. The state mine permit for major expansion was issued in July 2015, with BLM environmental impact statement approval expected in mid-2016.

Gas Hills – Strathmore had been working towards bringing its Gas Hills properties in central Wyoming into production, possibly in conjunction with Juniper Ridge, or with Sheep Mountain nearby, or both. In mid-2017 these two deposits were acquired by URZ Energy Corp.

New Mexico – Grants Mineral District

Roca Honda – Strathmore submitted a mining permit application in October 2009 (then 60% Strathmore, 40% Sumitomo). Original plans assumed a new mill, but the White Mesa mill about 180 km away is now expected to be used. In June 2015 EFRC bought URI's partly-developed adjacent Roca Honda mineral properties, and in 2016 bought out Sumitomo's 40% share for $6.3 million, giving it full ownership. Total measured and indicated resources are 6500 tU grading 0.41% U, with inferred resources of 4300 tU grading 0.40% U (February 2016). Production potential is about 1100 tU/yr over nine years.

Other deposits in the Grants district formerly held by the merged company included Marquez (3500 tU indicated resource), Dalton Pass (ISL potential, 1000 tU measured & indicated) and Nose Rock (deep hard rock, 1160 tU measured & indicated) – all NI 43-101 compliant. In November 2015 EFRC sold Marquez, Nose Rock and other small deposits in Arizona and Utah to Vancouver-based enCore Energy Corp.

Former Pinon Ridge Mill Project (Colorado)

EFRC in March 2011 had received a Colorado state licence to build the new 330 tU/yr Pinon Ridge mill for ore from its northern Arizona mines, plus possible toll treatment, but this was overturned on appeal in June 2012, pending a further public hearing. The state’s radioactive materials licence was reissued in April 2013, but plans were then put on hold, with the licence held in abeyance from 2014, and the project was sold to Western Uranium Corp. The company had been seeking $140 million finance for the mill, which would also produce 1700 t/yr of vanadium oxide.

The mill was then held by Pinon Ridge Resources Corporation (PRRC), associated with Western Uranium, but in April 2018 the state revoked the licence. PRRC was reported to be considering whether to appeal this or to apply for a new licence. In October 2024 Western Uranium & Vanadium Corp acquired Pinon Ridge Corporation, renaming the site Mustang Mineral Processing Site. The company is ramping up mining at its Sunday Mine Complex, with ore deliveries to the White Mesa mill beginning in early 2025, and is advancing licensing for the Mustang processing plant.

Western Uranium & Vanadium Corp.

Western Uranium Corp (formerly Homeland Uranium; renamed Western Uranium & Vanadium Corp in 2018) agreed in July 2014 to buy several non-core assets from EFRC for $33 million. These included eight mining properties along the Colorado-Utah border and the licence for the Pinon Ridge mill (see above). The mining properties comprise the fully-permitted Sunday complex, the Sage and Van 4 mines, and the Wilhunt, San Rafael, Farmer Girl, Dun and the Yellow Cat projects. Under the deal, EFRC receives a royalty of $3 per tonne on Pinion Ridge mill throughput, and one percent of sales.

In November 2019 the Colorado Court of Appeals ordered the Van 4 mine, inactive since 1989, to be closed and directed Pinon Ridge Mining LLC, a Western Uranium subsidiary, to comply with reclamation requirements. Other 'zombie' mines inactive for more than a decade may be subject to similar orders.

In mid-2015 Western Uranium & Vanadium announced NI 43-101 compliant measured and indicated resources of 390 tU at 0.21%U and 735 tU inferred resources at 0.31%U for the Sunday mine complex covering the southern third of the Uravan mineral belt in Colorado. In June 2019 the company launched the Sunday Mine Complex Vanadium Project with the opening of the Sunday and St Jude mine portals to focus on high-grade vanadium ore, averaging 3.15%. When previously mined from 2007 to 2009 it yielded a 6:1 ratio of vanadium to uranium. In mid-2021 the company resumed mining activities at the Sunday complex and moved the project's operations base from the St Jude to the Sunday mine. Underground drifting to access the GMG orebody (part of the Sunday complex) commenced late in 2021.

In 2015 Western Uranium Corp took over Black Range Minerals Ltd in a $14.5 million transaction, making it a subsidiary and acquiring the 11,500 tU Hansen and Taylor Ranch deposits in Colorado with 15,200 tU measured and indicated resources grading 0.053%U. Including inferred resources, the whole project has 35,000 tU grading 0.05%U. Hansen was licensed for mining in 1981, but stalled due to low uranium prices. In mid-2019 the company reported 'historic' resources of about 27,000 tU, mostly at Hansen and Taylor Ranch, and 13,500 t vanadium grading 1.4-2.2%.

Black Range has a joint venture with Ablation Technologies to commercialize its ablation mining technology (AMT), an ore beneficiation process applicable to sandstone deposits where the uranium and vanadium occur as a patina around sand grains. The process uses kinetic energy to abrade particles against one another without any chemicals, to detach the uranium and vanadium minerals. The resulting fine material is relatively high-grade beneficiated ore comprising 85-95% of the uranium and vanadium in 10-20% of the original mass. 

This 2015 JV agreement allows Western Uranium to utilize this technology at the Hansen-Taylor Ranch Project and at other projects. The merger terms with Western require Black Range to move an ablation pilot plant to its Sunday mine underground complex in southwest Colorado. A 5 t/h ablation unit is operating there, and a 20 t/h commercial-scale one was to join it by mid-2016. The company said: “Production tests indicate that the patented mining process could substantially reduce the cost of producing uranium concentrates from both the company’s mines, and potentially from other sandstone hosted deposits globally.”

In late 2016 Western Mining signed an agreement with Pinon Ridge Corporation to use ablation technology at its subsidiary’s mill. The technology is being evaluated by the Colorado Department of Public Health and the Environment (CDPHE) with advice from the NRC.

Uranium One

Toronto-based Uranium One's main interests are in ISL projects. The company was wholly-owned by Russia’s ARMZ, and its subsidiary Uranium One is responsible for all Rosatom’s uranium mining outside Russia. In December 2021 Texas-based Uranium Energy Corp (UEC) completed the acquisition of Uranium One Americas from the Russian parent company for $112 million, returning these assets to US ownership (see UEC section below), and the replacement of $19 million in reclamation bonds.

Wyoming Creek ISL project

In Wyoming’s Powder River Basin, Uranium One USA operated the Willow Creek ISL project from 2011 to July 2018. The project comprises several small mines and the Irigaray central processing plant, mostly acquired from Areva in 2009 for $35 million. In December 2010, the NRC licensed the Irigaray plant to produce up to 960 tU/yr (it operated at 500 tU/yr in 2011) and approved the restart of the nearby Christensen Ranch, which had been shut down since 2000 and restarted in January 2011. Production from its three small mines (Moore Ranch, Peterson Ranch, Nine Mile) and from Christensen Ranch itself is from loaded resin trucked to Irigaray from satellite plants. 

Overall Willow Creek produced 362 tU in 2013 at a cost of $36/lb and 217 tU in 2014. Wellfield development was put on hold in 2014 pending price improvement, and production wound down in 2015, continuing at a low level and with only 9 tU produced in the first half of 2018. Willow Creek total resources (NI 43-101) are 6500 tU. 

The Irigaray plant also toll-processed loaded resin from Peninsula’s Lance project on the east side of Powder River basin, pending construction of a plant there. In December 2016 it signed an agreement to toll process Anfield’s loaded resin also, to produce about 193 tU.

Other Powder River Basin projects

The NRC issued a licence to Uranium One Americas for Moore Ranch in October 2010, with production expected to start in 2012, but development has since been suspended. Additional projects in the Powder River Basin, including Ludeman, Allemand-Ross, Barge (1770 tU), Pine Tree and Ross Flats could be developed as satellite operations with final processing through the Irigaray central plant. Ludeman is quoted with 4200 tU total resources (NI 43-101) and is to be an extension of the Willow Creek project. Uranium One has some 4000 tU as measured resources (2235 t at Moore Ranch) and 23,000 tU as indicated resources in the state.

Great Divide Basin projects

Uranium One deposits in the Great Divide Basin of Wyoming are Antelope, JAB, Twin Buttes, Crooks Creek, Bull Springs, Stewart Creek, Cyclone Rim and West JAB. Plans for production from Antelope and JAB were deferred due to endangered species concerns.

Asset disposals

In 2010, Uranium One sold a number of Utah and Colorado claims and two Utah leases, including the Sage mine, to Colorado Plateau Partners (CPP), a joint venture between Energy Fuels of Toronto (see EFRC above) and Royal Resources of Australia.

In 2016 Uranium One sold 24 Wyoming properties in the Black Hills, Powder River Basin, Great Divide Basin, Laramie Basin, Shirley Basin and Wind River Basin areas to Anfield Resources for $6.55 million.

Uranium Energy Corp (UEC)

Uranium Energy Corporation (UEC) is the largest US uranium mining company following a series of acquisitions: Uranium One Americas (December 2021), UEX Corporation (August 2022), the Roughrider project from Rio Tinto (October 2022), and Rio Tinto’s Sweetwater plant and Wyoming uranium portfolio (December 2024, for $175 million).

Wyoming operations

UEC Wyoming hub is the Irigaray processing plant in the Powder River Basin, which supports ISL operations at Christensen Ranch and Reno Creek. In August 2024 UEC restarted uranium production at Christensen Ranch, with the first dried and drummed uranium concentrates produced at the Irigaray plant in February 2025. In September 2024 the Wyoming Department of Environmental Quality approved an increase of the Irigaray plant’s licensed capacity from about 960 to 1540 tU per year.

Reno Creek

In May 2017 UEC acquired 97% of the fully-permitted Reno Creek in Wyoming’s Powder River Basin from Pacific Road Resources Funds and the balance from the AUC subsidiary of Bayswater Uranium Corporation of Canada, which had a positive pre-feasibility study on mining its Reno Creek and Southwest Reno Creek deposits in Wyoming, held by its affiliate AUC. In 2017 UEC also purchased EFRC’s adjacent North Reno Creek property, adding 1650 tU measured and indicated resources at 0.048 %U and consolidating the holdings. UEC said that North and Southwest Reno Creek can now be developed together.

Reno Creek has a NI 43-101 measured and indicated resource of 10,000 tU @ 0.035%U (Jan 2019), suitable for ISL, plus a small inferred resource. The project would comprise up to 18 wellfields and a central processing plant producing 330 tU/yr initially, rising to 770 tU/yr as the market permits, and would take 18 months to bring online. It is located 30 km southeast of Uranium One’s Willow Creek, 50 km north of Cameco’s Smith Ranch, and 130 km northeast of Casper.

In July 2015 the Wyoming Department of Environmental Quality (WDEQ) Land Quality Division issued AUC a permit to mine for the Reno Creek uranium project, producing up to 770 tU per year. In February 2017 the NRC issued an operating licence for the project at this production level, though AUC said it did not intend to proceed immediately.

Texas operations

UEC in October 2009 bought the small but recently-refurbished Hobson mill in southern Texas from Uranium One (it had been shut since 1991). UEC then made Hobson the basis and hub of its Texas uranium projects. The Hobson plant is licensed for up to 1540 tU/yr.

Production commenced at Palangana in November 2010 – the first US ISL operation to start in five years – but there has been no production since 2015. Palangana has 410 tU measured and indicated resources grading 0.114%U in two orebodies and 445 tU inferred resources at 0.15%U in six others. Palangana’s mine area permit was renewed in March 2024.

The Goliad ISL project, 70 km east of the Hobson mill, received all necessary permits by the end of 2011, with production originally anticipated from mid-2014. It has 2100 tU measured & indicated resources at 0.04%U, all NI 43-101 compliant. Its radioactive material licence was renewed in March 2024. 

Burke Hollow, 86 km southeast of Hobson, has an inferred resource estimate of 2700 tU. Construction is complete, including 129 injection and recovery wells and a satellite ion exchange plant. The project is awaiting final TCEQ approval for startup.

Arizona projects

The Anderson project, northwest of Phoenix in central west Arizona, was formerly mined in 1950s, yielding 12,800 tU. It has 6000 tU indicated and 960 tU inferred resources at 0.024%U accessible by open pit mining, with two-thirds as much again (mostly inferred) accessible underground (NI 43-101). UEC expects to produce 6200 tU over 14 years using heap leach, with loaded resin transported to White Mesa mill in Utah.

Acquired in 2007, the Los Cuatros Uranium Project (formerly New River) in central Arizona has a historic resource estimate of 5000 tU in shallow low-grade ore. Its Workman Creek deposit there has 2100 tU inferred resource at 0.073%U.

Colorado

UEC’s Slick Rock project in western Colorado has 4470 tU grading 0.19%U. Vanadium is also present. Several other prospects are nearby.

Cameco

Cameco's US subsidiary, Cameco Resources Inc, holds two ISL mines: Smith Ranch-Highland mine in Wyoming's Powder River Basin and the Crow Butte mine in Nebraska. Together they produced nearly 1200 tU between them in 2009, but production was curtailed from 2016 due to market conditions and both have been on care and maintenance since 2018 with no commercial production. Cameco expects ongoing care and maintenance costs of $14-15 million per year for each.

Smith Ranch-Highland has a licensed wellfield capacity of 1156 tU and produced 815 tU in 2014 (including output from North Butte), but has declined from that level since. North Butte-Brown Ranch is a satellite plant about 40 km north in the same Powder River Basin which that started production in May 2013 and is capable of ramping up to 270 tU/yr. Reserves total 3080 tU, plus 11,000 tU measured and indicated resources (as of December 2015).

Crow Butte, in northwest Nebraska near the borders of Wyoming and South Dakota, has a licensed capacity of 770 tU and it has 5800 tU resources grading 0.22%U. In September 2024 Cameco applied for a 20-year licence renewal, signalling a potential long-term restart rather than permanent closure.

Cameco also has the Gas Hills-Peach project 90 km west of Casper in Wyoming which is permitted but on hold, with 5100 tU measured and indicated resources.

URI / Westwater Resources / enCore Energy

URI – Texas operations

Uranium Resources Inc (URI) began operations in 1977 in south Texas. It developed and produced over 216 tU from the Longoria and Benavides projects in the early 1980s, then 2350 tU from Kingsville Dome and Rosita through to 1999.

URI commenced production from its Vasquez ISL mine in 2004 at about 50 tU/yr and from Kingsville Dome in 2006. Vasquez peaked in 2006 and is now depleted (30 tU in 2007, 9 tU in 2008). Kingsville Dome produced 67 tU in 2008 and 19 tU in 2009 before closing in June 2009 due to low uranium prices. Rosita restarted production in 2008 with oxygen injection but was then closed as uneconomic after 3 tU was recovered. All three wellfields have since been remediated using reverse osmosis. The 300 tU/yr Kingsville Dome plant is being maintained on standby, with potential for accepting resin from four satellite IX plants.

URI earlier said that it did not intend to revive its Texas operations, with total reserves at Kingsville and Rosita wellfields of only 260 tU. However, in December 2013 it said that it remained “committed to developing uranium in south Texas as we aim to leverage our two processing plants in the region” – Kingsville Dome and Rosita. Butler Ranch, also ISL and acquired in 2014, is 160 km north of the Kingsville Dome plant, and Rosita is 65 km northwest of the plant. In 2015 URI was actively evaluating Butler Ranch and Alta Mesa Este.

URI – New Mexico operations

URI owned several Grants mineral belt properties in western New Mexico which hold 39,000 tU, and from which it hoped to produce 2000-3000 tU/yr from ISL. Its subsidiary Hydro Resources Inc was licensed in 1994 to mine the Crownpoint and Church Rock ISL deposits. After years of opposition, the licence was validated by the Nuclear Regulatory Commission in 2006 and then reactivated in 2011. URI planned to produce 385 tU/yr from Church Rock/Mancos from 2013, as the first of URI’s New Mexico properties to be developed, subject to further permitting. Other URI properties in the Grants mineral belt included Nose Rock, Roca Honda and West Largo/Ambrosia Lake. URI also had a licence to build a processing plant in the area.

In 2007 URI sought to buy Rio Algom Mining, with uranium properties and a licensed mill site at Ambrosia Lake, where it planned to construct a new mill to serve the Grants mineral belt. However, the deal was aborted in mid-2008.

In June 2015 URI sold its partly-developed Roca Honda mineral properties adjacent to EFRC’s Roca Honda project to EFRC, while retaining some royalty rights. In partial exchange it received from EFRC claims adjacent to its Church Rock prospect, with a historic resource estimate of 4200 tU based on a previous owner’s 1979 data. Following the takeover of Anatolia Energy, in November 2015 URI agreed to sell its Crownpoint and Church Rock properties to Laramide Resources for $12.5 million. This was confirmed in April 2016 by way of selling Hydro Resources Inc and finalized at the end of that year.

URI – other properties and Antatolia Venture

URI also holds the Copper Mountain leases in Wyoming, with low-grade uranium mineralization (hardrock, not ISL) which was mined to 1971.

In June 2015 URI announced a takeover of Anatolia Energy, which was developing the Temrezli ISL uranium mine in Turkey. The deal was effectively a merger, with URI shareholders retaining about 59% of the combined company. URI planned to relocate the Rosita processing plant to Turkey and complete a capacity doubling to 600 tU/yr – work that had been halted in 2008. However, in June 2018 The Turkish government expropriated all the company's leases. The projects were owned by its Turkish subsidiary Adur Madencilik Limited Sirketi, which had held exclusive rights for the exploration and development of uranium there since 2007 and had invested heavily in them. In December 2018 Westwater Resources (as URI had then been renamed) filed a request for arbitration.

Transition to Westwater Resources

In August 2017 URI changed its name to Westwater Resources (WWR) to reflect its shifting business plan towards lithium production “while maintaining optionality in the case of a future rising uranium price.” In September 2020 the company announced that it was selling its US uranium assets to enCore Energy for $1.95 million, completed in January 2021.

enCore Energy

EnCore Energy Corp (Vancouver) entered the uranium sector by purchasing Marquez, Nose Rock, and other small deposits from EFRC in November 2015. It subsequently expanded through a series of acquisitions:

• January 2021 – acquired Westwater Resources' US uranium assets.
• January 2022 – completed its merger with Azarga Uranium Corp, consolidating about 35,000 tU in measured and indicated resources across multiple US states. The deal brought in the Dewey-Burdock project in South Dakota, the Gas Hills project in Wyoming, and the Centennial project in Colorado (see below). Azarga had itself acquired Gas Hills in 2018 through a merger with URZ Energy (formerly Summit Point Uranium Corp).
• February 2023 – acquired the Alta Mesa ISL project in Texas from EFRC for $120 million adding the Dewey-Burdock project in South Dakota and Wyoming ISL prospects to its portfolio.

enCore restarted uranium production at the Rosita plant in November 2023 – the first uranium production in Texas in over a decade. The plant is licensed for about 310 tU/yr. The Alta Mesa Central Processing Plant was commissioned in June 2024 under a 70/30 joint venture with Boss Energy. Combined production from Rosita and Alta Mesa in 2024 was about 111 tU (288,589 lbs U₃O₈ captured), making enCore the largest US uranium producer by volume that year.

In April 2025 enCore sold its New Mexico assets (Crownpoint, Hosta Butte, Nose Rock, West Largo, and Ambrosia Lake–Treeline) to Verdera Energy Corp.

Key development projects (acquired via Azarga):

• The Dewey-Burdock project in South Dakota holds NI 43-101 compliant resources of 5,500 tU measured (averaging 0.11% U) and 1,100 tU indicated (averaging 0.06% U), amenable to in-situ recovery (ISR). The NRC source material licence became final in 2023, and in 2025 the EPA underground injection control permits were upheld on appeal after the EPA Environmental Appeals Board denied a petition against them. In August 2025 the project was designated for FAST-41 accelerated federal permitting. Permitting completion is forecast for Q3 2026, with construction anticipated in early 2027.
• The Gas Hills project in Wyoming hosts NI 43-101 compliant measured and indicated resources of 4,140 tU at 0.077% U, of which 72% is amenable to in-situ leach (ISL). Early-stage permitting for ISR operations is under way.

The Centennial project in northern Colorado, close to the Wyoming border, holds 4,000 tU indicated resources at 0.08% U.

Ur-Energy

Ur-Energy Inc (URE/URG) has its main operation at Lost Creek in the Great Divide Basin of Wyoming. The mineral resource has been expanded to 4580 tU measured and indicated and about 4000 tU inferred. In May 2025 the Wyoming DEQ issued a permit for six additional mine units and the EPA approved a final aquifer exemption, extending the mine life by about three years. The site is close to Rio Tinto's Sweetwater mill.

Production from Lost Creek commenced in mid-2013 after construction of a 770 tU/yr mill. After peaking in 2015 production was reduced from 2016 in response to low uranium prices, and the mine was placed on standby in late 2019. Commercial production restarted in 2023, with output of about 102 tU in 2024 and 158 tU in 2025.

Ur-Energy’s Shirley Basin project in Wyoming, 150 km east of Lost Creek, has measured and indicated resources of 3400 tU grading 0.194%U. The ground was previously held by Pathfinder Mines Corp which Ur-Energy acquired in 2013, and it was mined conventionally to 1992, producing 10,800 tU. Construction of the Shirley Basin satellite plant is well advanced, with all ion exchange columns installed and 469 wells pilot drilled in Mine Unit 1 by February 2026. It is licensed for 385 tU/yr from the wellfield, with yellowcake production expected in mid-2026.

Peninsula / Strata

Australian-based Peninsula Energy commenced production from its Lance ISL project on the east side of Wyoming’s Powder River Basin early in 2016, operated through its subsidiary Strata Energy Inc. It has JORC-compliant resources (December 2017) of 20,700 tU at 0.04%U at Lance, including 6080 tU as measured and indicated resources. Vanadium is a potential by-product – 2237 t V₂O₅ resources are identified for Ross and Kendrick.

The project was originally planned as a three-stage ramp-up eventually to 1150 tU/yr from three production units – Ross, Kendrick and Barber – feeding a central processing plant with an expandable capacity of up to 1154 tU per year (four modules of 288 tU/yr), commencing from Ross. The plant incorporates a restoration circuit with resin ion exchange (IX) then reverse osmosis (RO) to restore water quality of barren liquor to pre-mining levels. A deep disposal well has been drilled to 2600 metres to a sandstone aquifer with low water quality.

A state mining permit was issued in November 2012. The US Nuclear Regulatory Commission (NRC) granted a source materials licence and issued a final supplemental environmental impact statement covering both the plant and the Ross wellfield in March-April 2014, and authorised operation of the Ross wellfield in November 2015. Under stage 1, loaded resin was trucked 90 km west to Uranium One’s Irigaray plant for elution. Stage 2 was to expand the ion exchange capacity and bring the elution, precipitation, drying, and packaging processes in-house at the new central plant. The Kendrick, Richards and Barber production units to the south of Ross were to be brought online with amendments to Ross licences, the Barber wellfield and satellite plant being part of stage 3 ramp-up.

In July 2015 Peninsula agreed to buy the nearby Hauber project from Aldershot Resources as a likely satellite operation for Lance. Homestake had produced about 1000 tU in 1950-60s from Hauber, and Bayswater Uranium was farming into the project in 2011. Aldershot reported only about 250 tU resources NI 43-101 compliant, but estimated a total of 1400 tU.

In March 2016 Peninsula announced a long-term sales contract for 1540 tU over 2020-30 with a major European utility, with a provision to increase deliveries to half of the Lance output from 2026. This added to existing contracts totalling 3045 tU with US and European utilities. First product was delivered in May 2016, and 2016 production reached 49 tU.

In October 2017 the company announced that it was seeking an amendment to its licence so that it could use "low-pH recovery solution" (acid leaching) instead of alkaline at Lance. Tests had shown a huge increase in recovery, which had proved to be minimal with alkaline leaching, the comparative figures being 95% instead of 35%. The change would make Lance the only ISL operation in the USA with acid leach. Alkaline leaching continued pending the amendment. Field trials of acid leaching commenced in December 2018 and in November 2019 the state environment department approved the change. The company said that its survival depended on the change.

Uranium production was stopped at Lance in July 2019, before the licence change. In November 2022 Peninsula Energy decided to resume operations using the low-pH ISR method. After several delays, production restarted in December 2024, making Lance the only US ISL operation with acid leach. Operational challenges then led to revised production guidance of up to 19 tU for calendar year 2025, well below initial expectations, and the company terminated five of its six offtake contracts. Production guidance for 2026 is 155-195 tU. The Ross central processing plant has a capacity of about 770 tU per year of dried yellowcake.

Azarga Uranium

Azarga Uranium Corp was acquired by enCore Energy in January 2022, with all of Azarga’s assets passing to enCore through the transaction.

Anfield Energy

Vancouver-based Anfield Energy has 1780 tU at 0.25%U as measured and indicated resources at Velvet-Wood in Utah, the Frank M project in Utah, and a 50% interest in the Wate deposit in Arizona (432 tU). Additional conventional mining properties are held in Colorado. All of Anfield's conventional uranium properties lie within 200 km of its Shootaring Canyon mill.

In June 2016 it reported a preliminary economic assessment of the licensed Velvet-Wood project using heap leach or vat leach methods. The two scenarios show an average output of 243 tU per year, for a total production of 1770 tU over a seven-year mine life, with capital expenditure of about $46 million and direct operating costs of around $11 per pound. Ground was broken at the Velvet-Wood uranium-vanadium mine in November 2025, with first production possible in 2026.

The Shootaring Canyon mill

Anfield’s ‘key asset’ is the 1000 t/day Shootaring Canyon mill in Utah, acquired from Uranium One together with small onsite stockpiles. The mill was built in 1980 but closed in 1982 Uranium One had bought it in 2007*, along with associated properties in four contiguous states for $50 million plus royalties, from US Energy. US Energy had previously planned to restart the mill at a cost of $31 million.

* In a separate 2007 transaction, Uranium One had also secured the right to buy Rio Tinto's 3000 t/day Sweetwater uranium mill and associated properties in south-central Wyoming for $110 million, but Rio Tinto cancelled the deal in January 2007.

In October 2013 Uranium One agreed to sell the mill to Black Range Minerals for $10 million, alongside a joint venture covering all of Uranium One's associated conventional hard-rock leases, under which Black Range would progressively increase its equity. The deal lapsed due to regulatory problems, and Black Range refocused on its Hansen project. In October 2014 Anfield Resources agreed to buy the mill and associated mining properties in three states – including Velvet-Wood – for $5 million. In October 2014 the Utah regulator agreed to transfer the licence to Anfield Resources, giving it one year to apply for licence renewal with necessary upgrades. In April 2024 Anfield submitted an application to reactivate the mill, including upgrading throughput to 1000 t/day and tripling its licensed annual uranium production capacity.

Wyoming ISL properties

In September 2016 Anfield completed the purchase of 24 Wyoming ISL properties in the Black Hills, Powder River Basin, Great Divide Basin, Laramie Basin, Shirley Basin and Wind River Basin areas from Uranium One for $6.55 million. The transaction also included a resin processing agreement with Uranium One to toll process up to 193 tU per year of Anfield’s loaded resin at Uranium One's Irigaray plant.

In March 2018 Anfield agreed to purchase the Charlie project in the Pumpkin Buttes area of Powder River Basin from Cotter Corporation. The Charlie project has The Charlie project, with state mining lease and 1190 tU indicated resources.

NI 43-101 resource estimates for the Wyoming properties are being prepared and progressively published. Those for Red Rim, Clarkson Hill and Nine Mile had been completed by mid-2018, showing a total of 1405 tU indicated and 1718 tU inferred resources.

Proposed IsoEnergy acquisition

In October 2024 IsoEnergy announced a proposed acquisition of Anfield Energy for about $127 million, but the deal was terminated in January 2025.

Laramide Resources

Laramide Resources' portfolio includes ISR and hard rock assets in Utah (La Sal) and New Mexico (Churchrock-Crownpoint, and La Jara Mesa).

Laramide Resources bought the La Sal mine in Lisbon Valley, Utah, in 2010 from Homestake. The small-scale underground project is about 90 km from Energy Fuels' White Mesa mill, and in January 2013 a toll milling agreement was entered into whereby Energy Fuels’ White Mesa mill would process all material produced by La Sal.

In April 2016 Laramide bought URI’s subsidiary Hydro Resources Inc to obtain the Church Rock and Crownpoint ISL properties in New Mexico for $12.5 million. The NRC has granted a licence for production of uranium from sections of both projects. A preliminary economic assessment published in January 2024 showed a 62% pre-tax IRR for Church Rock, projecting a 31-year operational lifespan producing about 12,000 tU (31.2 million lbs U₃O₈) using ISR at an all-in sustaining cost of about $35/lb.

Laramide also has the La Jara Mesa underground project in the Grants Mineral Belt of New Mexico, with 18,500 tU indicated resources. In June 2025 La Jara Mesa was also designated a FAST-41 Covered Project.

In June 2025 both Church Rock and La Jara Mesa were designated FAST-41 Covered Projects, qualifying them for accelerated federal permitting.

General Atomics and affiliates

General Atomics affiliate Heathgate Resources has operated the Beverley/Four Mile ISR uranium mine in South Australia for over 25 years. In November 2024, the company announced its plans for a second uranium in-situ recovery operation – the Grants Precision ISR Project – in Cibola and McKinley counties, New Mexico. The company is actively proceeding with permitting, licensing, and stakeholder engagement activities. Grants ISR was the first uranium ISR project listed on FAST41. The Grants Precision ISR Project will develop the large and well-delineated Mt Taylor deposit using ISR. The updated ISR resource was estimated at 260 million pounds of uranium making it the largest contiguous uranium resource in the US. Closure activities associated with the Mt Taylor conventional mine are proceeding separately.

History

The Mt Taylor Mine, located at the eastern end of the prolific uranium trend within the San Juan Basin in northwest New Mexico, has played a significant role in the region’s uranium production history. The mine is situated near the community of San Mateo and is part of the Ambrosia Lake subdistrict – one of several subdistricts within the larger Grants Mining District. The Grants district itself has yielded approximately 340 million pounds of uranium, with about 210 million pounds recovered from the Ambrosia Lake subdistrict alone, primarily through conventional underground mining methods.

Initial development and production at the Mt Taylor Mine began under the ownership of Gulf in the 1980s, followed by a brief period of operation by Chevron. In 1991, Rio Grande Resources Corporation (RGR), a subsidiary of General Atomics Uranium Resources, acquired the mine. Prior to RGR's acquisition of Mt Taylor, approximately 8 million pounds of uranium were extracted through conventional or “shaft” mining and milling, a fraction of the deposit's full potential.

In 2006 and 2008, RGR commissioned Chapman, Wood, and Griswold (CWG) to perform detailed resource estimates for the deposit area. CWG’s reports classified the uranium resources in accordance with Canada’s National Instrument 43-101, a widely accepted standard for mineral project disclosure. Their estimates drew on both contemporary data and earlier studies such as Gulf Mineral Resources Co. (Christiansen, 1984), providing a robust geologic and resource foundation for the property.

Transition from Conventional to ISR

Recognizing the changing landscape of uranium extraction technologies and the need for more environmentally sustainable approaches, RGR assessed the feasibility of transitioning from conventional underground mining to ISR methods over years of study. The transition expanded the resource base to include additional sections, such as 13 and 15 in Township 13N, Range 8W, and reflected a strategic shift in project development.

Grants ISR launched

This evolution culminated in the Grants Precision ISR project, which aims to extract uranium from the extensive resource using modern ISR technology. The Grants Precision ISR project is expected to produce from the early 2030’s with a planned mine life of 30 years.

Others

ISL

In New Mexico, Uranium International Corp (UIC) has announced 1180 tU measured and indicated resource at Dalton Pass, with ISL potential. It also announced a 1160 tU measured and indicated resource at Nose Rock, deep in hard rock. Both are NI 43-101 compliant, in the Grants mineral belt and owned by Strathmore Minerals. UIC has the option of earning a 65% share of each.

In Colorado, Perth-based Global Uranium and Enrichment (formerly Okapi Resources) has the Tallahassee Uranium Project with an overall JORC resource of about 20,100 tU (52.2 million lbs U₃O₈) in paleochannels 100 to 270 metres deep across five deposits. The company completed a scoping study for the Hansen deposit in May 2025 and has approval to drill for exploration and hydrological testing through 2027.

Hardrock

Neutron Energy Inc has taken full ownership of the Cebolleta Land Grant in New Mexico which has 8000 tU. Earlier mining on the property took place 1975-81, producing 460 tU.

Yellowcake Mining Corp reported 5000 tU in reserves at its planned Beck mine in the Uravan area of Colorado and in May 2008 agreed to sell a 50% stake in it to Korea Electric Power Corp (KEPCO). KEPCO withdrew in February 2009, leaving the project bereft of funds. Yellowcake’s joint ventures with Strathmore Minerals for Juniper Ridge and a Gas Hills prospect in Wyoming were terminated in 2008. Strathmore subsequently agreed in 2010 to sell Juniper Ridge to Crosshair Energy, but that deal was terminated in 2012.

Crosshair Energy has the Bootheel project in Wyoming with about 1780 tU resources.

Bluerock Energy Corporation shipped the first ore from development of the J-Bird mine in Colorado to Denison's White Mesa mill in Utah.

In January 2017 Mesa Exploration acquired the Noah uranium prospect in Utah’s Lisbon Valley mining district on the Colorado Plateau, 96 km north of the White Mesa mill.

Australia’s TNT Mines is exploring the San Juan County area of Utah, including the East Canyon uranium-vanadium project area.

In July 2021 Vancouver-based International Consolidated Uranium agreed to buy the Daneros, Tony M and Rim mines in Utah from EFRC. Consolidated Uranium then merged with IsoEnergy in December 2023. IsoEnergy reopened the Tony M underground mine in July 2024 and, in late December 2025, launched a bulk sample program to extract up to 2000 tonnes of mineralized material over 12-14 weeks to support a potential production restart decision Stock TitanPR Newswire. The material is being trucked to Energy Fuels' White Mesa mill in Utah for processing under an existing toll-milling agreement.

In Virginia, the Coles Hill deposit in Pittsylvania County contains 3260 tU as measured resource and 42,800 tU as indicated resource at 0.05% U (NI 43-101 compliant), making it the largest known undeveloped uranium deposit in the USA. Virginia Uranium Inc sought to mine it but was blocked by the state's 1982 moratorium on uranium mining. The company challenged the state's authority to enact the ban and asked the courts either to compel Virginia to allow mining under the company's constitutional property rights or to award compensation for the "full value" of the resource – some $6 billion. In June 2019, the US Supreme Court upheld the moratorium in Virginia Uranium v. Warren, and the project cannot proceed.

In Texas, Texas Rare Earth Resources Corp signed an agreement with Areva (now Orano) to take up to 116 tU per year by-product uranium from its Round Top heavy rare earth project in Hudspeth County. About 37,000 tU is identified in all classes of REE resources there.

US in situ leach (ISL) uranium mines and production facilities

Company	Mines / plant	Location	Capacity (tU)	Status
Cameco	Crow Butte Operation	Dawes, Nebraska	385	Restoration
enCore Alta Mesa, LLC	Alta Mesa Project	Brooks, Texas	577	operating
enCore Energy Corporation	Dewey Burdock Project	Fall River and Custer, South Dakota	385	permitted and licensed
enCore Energy Corporation	Kingsville Dome Project	Kleberg, Texas	308	standby
enCore Energy Corporation	Rosita Project	Duval, Texas	308	operating
Lost Creek ISR LLC	Lost Creek Project	Sweetwater, Wyoming	769	operating
Pathfinder Mines Corporation	Pathfinder Shirley Basin	Carbon County, Wyoming	539	developing
Power Resources Inc., dba Cameco Resources	Smith Ranch-Highland Operation	Converse, Wyoming	2116	operating
Strata Energy Inc	Ross CPP	Crook, Wyoming	1154	operating
Uranerz Energy Corporation (An Energy Fuels company)	Nichols Ranch ISR Project	Johnson and Campbell, Wyoming	769	standby
Uranium Energy Corp	Burke Hollow ISR Uranium Project	Bee County, Texas	385	under construction
Uranium Energy Corp	Goliad ISR Uranium Project	Goliad, Texas	385	permitted and licensed
Uranium Energy Corp	Hobson ISR Processing Plant	Karnes, Texas	1539	standby
Uranium Energy Corp	Jab and Antelope	Sweetwater, Wyoming	769	developing
Uranium Energy Corp	La Palangana ISR Uranium Project	Duval, Texas	385	standby
Uranium Energy Corp	Moore Ranch	Campbell, Wyoming	1154	permitted and licensed
Uranium Energy Corp	Reno Creek ISR Uranium Project	Campbell, Wyoming	769	permitted and licensed
Uranium Energy Corp	Willow Creek Project (Christensen Ranch and Irigaray)	Campbell and Johnson, Wyoming	500	operating

US hard rock uranium mines and mills

Company	Mill and heap leach facility	Location	Capacity (short tons ore per day)	Status
Anfield Resources	Shootaring Canyon	Garfield, Utah	750	Standby
EFR White Mesa	White Mesa Mill	San Juan, Utah	2000	Operating
Energy Fuels Wyoming	Sheep Mountain	Fremont, Wyoming	725	Partially permitted and licensed
Kennecott Uranium Company / Wyoming Coal Resource Company	Sweetwater Uranium Project	Sweetwater, Wyoming	3000	Standby

Legacy environmental issues

Uranium mining was a major activity in the late 1940s and into the 1950s, when the focus was on national security rather than environmental protection. There was little regulation or oversight of facilities, and tailings were put in impoundments without liners, giving rise to groundwater contamination.

There was a considerable legacy of pollution from hundreds of abandoned uranium mines and treatment plants, most government-sponsored and dating from the 1950s. This problem was addressed in the 1980s. For instance, the Uravan mill site on the San Miguel River in Colorado was designated a Superfund site and was cleaned up between 1987 and 2007 at a cost of over $120 million. Historic mining and milling at Uravan included the production of radium, vanadium and uranium, leaving radioactive residues from the early 1900s through to the mid-1980s. From the time Uravan mill began operating in the 1920s until it was shut down, it processed over ten million tonnes of uranium-vanadium ore, giving rise to a similar amount of uncontained tailings, and 1,440 megalitres of liquid wastes were treated in the site rehabilitation program.

The Schwartzwalder mine west of Denver, Colorado, was once the largest underground uranium mine in USA. It has been polluting Ralston Creek feeding the city's water supply and is now subject to bacterial bioremediation by Cotter Corp.

In 2015, the US Department of Justice announced that $13.2 million in federal funding will be placed into a trust to pay for evaluations of abandoned uranium mines across Navajo lands in Arizona, New Mexico, and Utah. This will expedite the cleanup of 16 mines seen as the most significant hazards. The funding is part of an ongoing multi-agency federal initiative to address legacy issues connected with historic uranium mining across the Navajo Nation which produced four million tonnes of uranium ore between 1944 and 1986. According to the US Environmental Protection Agency (EPA) website: “Nearly 30 million tons of uranium ore were extracted from Navajo lands under leases with the Navajo Nation” over this period.

In 2017 the NRC ordered Homestake Mining to undertake groundwater remediation at the site of a mill which operated near Grants in New Mexico from 1958 to 1990. In 1975 it was discovered that seepage from 22 million tonnes of tailings in two impoundments had contaminated groundwater aquifers, and a groundwater protection plan was implemented from 1977. The site is also under the oversight of the US EPA through the Superfund programme. Homestake submitted a revised groundwater monitoring programme to the NRC for this Grants Reclamation Project in August 2018.

The versatile White Mesa mill in Utah operated by EFRC is able to re-treat some of the mine residues and recover some uranium from them to help clean up old mine sites.

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Notes & references

References

1. US uranium mine production and number of mines and sources, Domestic Uranium Production Report – Annual, US Energy Information Administration [Back]

General sources

US Energy Information Administration
Company reports

Related information

Uranium Mining Overview
USA: Nuclear Fuel Cycle