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Uranium in Namibia

(10 February 2010)

  • Namibia has two significant uranium mines capable of providing 10% of world mining output.
  • Its first commercial uranium mine began operating in 1976.
  • There is strong government support for expanding uranium mining and some interest in using nuclear power.

Uranium was discovered in the Namib Desert in 1928, but was not until intensive exploration got under way in the late 1950s that much interest was shown in Rossing. Rio Tinto discovered numerous uranium occurrences and in 1966 took the rights over the low-grade Rossing deposit, 65 km inland from Swakopmund.

Rossing Uranium Ltd was formed in 1970 (now 68.6% Rio Tinto, 15% Iran, 10% Industrial Development Corporation of South Africa, 3% Namibian government). The company has mined the deposit from 1976 as a large-scale open pit in very hard rock. Rossing has nominal capacity of 4000 tU/yr and to the end of 2009 had supplied 94,963 tU. In 2009 it produced 3519 tU (2008: 3449 tU, 2007: 2582 tU, 2006: 3067 tU), making it the third largest uranium mine in the world.

Rossing uranium resources

End 2008 Reserves Resources


proven
probable
measured
indicated
inferred
Contained:

11,970 tU
53,070 tU
1,900 tU
19,500 tU
3,000 tU
Ore grade:

0.035% U
0.034% U
0.022% U
0.021% U
0.023% U

Rossing's uranium is sold to power utilities in Central Europe, North America and South-East Asia including China.

After three years evaluation it was decided in December 2005 to invest US$ 112 million to further develop the Rossing mine, extend its life to 2016 and increase the output to 3400 tU/yr. In 2007 Rio Tinto proposed a further expansion to 3800 tU/yr and extending mine life. The first phase extends mining in 2008 to a new small orebody, introduces radiometric ore sorting to beneficiate material from stockpiled coarse ore, and commissions a new 1200 t/day sulfur-burning acid plant also producing 9.5 MWe net of electricity. Phase 2 defined in 2008 includes heap leaching of low-grade ore and development of other small satellite orebodies with different mineralisation and hence needing a new treatment plant for them.

2007 was a year of consolidation, preparing for increased production. Unit costs therefore rose to US$ 38 per pound ($99/kgU) from $22 ($57/kgU) in 2006. In 2008 production was 2370 tonnes U and is on target for 3800 tU for 2012 onwards.

Two other significant deposits found in early exploration were Trekkopje, a calcrete deposit 80km NE of Swakopmund and near Rossing, and Langer Heinrich, a calcrete deposit discovered in 1973 by Gencor, 80 km inland from Walvis Bay and 50 km southeast of Rossing.


deposit type Known Resources


Measured & indicated
Inferred
Langer Heinrich
palaeochannel 32,800 tU in 0.06% ore 32,200 tU in 0.06% ore
Trekkopje
palaeochannel 45,500 tU in 0.011% ore 3,000 tU in 0.01% ore
Rossing South
hard rock
9,250 tU in 0.038% ore 93,660 tU in 0.0415% ore
Valencia hard rock 21,500 tU in 0.016% ore 4,200 tU in 0.012% ore
Etango
hard rock 41,500 tU in 0.021% ore 20,000 tU in 0.0197% ore
Marenica palaeochannel
13,000 tU
Tubas palaeochannel 15,000 tU in 0.019% ore

Paladin's Langer Heinrich is 50 km south-southeast of Rossing, in the Namib Park, and 80 km from the coast. It was acquired by Acclaim Uranium Ltd (now Aztec Resources Ltd) in 1999 and then bought by Paladin Resources Ltd (now Paladin Energy) in 2002. The open pit mine commenced operation late in 2006 with 1000 tU/yr capacity. The ore occurs over 15 km in a palaeochannel system, some 50m deep. Some vanadium is present in the carnotite mineral. There is a conventional hard rock mill with an alkaline leaching circuit.

Production in 2009 was 1108 tU (2008: 919 tU) and steadily improving to reach nameplate capacity in October. Stage 2 development boosted production to 1430 tU/yr in 2009, and Stage 3 is planned to take production to 2000 tU/yr from 2010 at a cost of US$ 100 million. A heap leach to produce about 400 tU/yr from low-grade ore by mid 2014 is proposed for stage 4, in moving towards 3500 tU/yr production level.

Reserves are 25,000 tU at 0.025% cut-off (JORC and NI 43-101 compliant) plus 1500 tU in stockpiles. Inferred resources are 32,200 tU, and it is expected that much of this will be upgraded with infill drilling. A further 12,000 tU will end up in low-grade stockpiles at the end of mining, and may be recovered then.

Rossing South: Extract Resources Ltd based in Perth is undertaking a feasibility study for mining the Rossing South orebody about 7 kilometres south of the Rossing mine. In July 2009 it announced that its indicated and inferred resource for Zone 1 had increased from 41,600 tU to 55,900 tU averaging 0.0381%U (JORC and NI 43-101- compliant). This was with 100 ppm cut-off and still open along strike and dip. The company called it the highest grade granite-hosted uranium deposit in Namibia, and it is an extension of the Rossing stratigraphy. So far, little more than 2.2km of 15km strike on the company's lease – contiguous with Rossing - has been drilled. It lies under a shallow (50m) alluvial sand cover.

Inferred resources in Zone 2 are 47,000 tU averaging 0.046%U, making 103,000 tU averaging 0.041%U proven so far. It is part of the company's Husab project, which includes the Ida Dome further south. Rio Tinto has increased its direct equity in Extract to 15.6%, and Kalahari Minerals owns 40%.

Extract Resources plans to produce at a rate of 5700 tU/yr from an open pit. Capital costs are estimated at US$ 700 million, and operating cost $61 /kgU. No time line is given.

Areva's Trekkopje is about 80 km northeast of Swakopmund, and 35 km north of Rossing. In 2007 UraMin Inc announced an upgrade of uranium resources at this project, comprising two adjacent palaeochannel deposits (Klein Trekkopje being the main one) over an area about 16 km by 1 to 3 km. The company was then taken over by Areva to become Areva Resources Southern Africa, with subsidiary Areva Resources Namibia developing the mine.

The US$ 750 million project will have a shallow open-pit mine and a sodium carbonate/ bicarbonate heap leach process - the first one in the world. 80 percent of the ore is less than 15 metres deep. Water is to be supplied from a coastal desalination plant with about 55,000 m3/day output and requiring 16 MWe from the grid.

A substantial conversion of 'inferred' resources to reserves occurred as a result of drilling in 2006 and 2007, taking the Measured and Indicated resource category to 42,000 tU in the main deposit. Areva quoted 45,600 tU resources in 2008. Over 9000 tonnes of vanadium pentoxide by-product is envisaged. A mining licence was granted in June 2008 and production is expected to commence at the end of 2009, ramping up to 3500 tU/yr in 2011.

Valencia: Forsys Metals Corp. of Toronto is developing the Valencia uranium project along strike from Rossing and 25 km northeast of it, with geology (alaskite) similar to Rossing. Environmental approval for an open pit mine was granted in June 2008 and a mining licence was granted in August 2008 to Valencia Uranium P/L (a wholly owned subsidiary of Forsys), allowing production to begin in 2012 at 1350 tU/yr and ramp up to about 2200 tU/yr. Measured and indicated resources figures to 21,546 tonnes U at 0.016% U3O8 with 0.01% cut-off or 29,000 tU at 0.127% U3O8 with 0.006% cut-off were announced in December 2009. This includes reserves of 19,000 tU at 0.0194% U3O8 with 0.01% cut-off. The open pit will be 1600 x 1000 metres and 375 m deep.

Etango (formerly Goanikontes): In August 2009 Bannerman Resources Ltd announced indicated resources of 41,500 tU and inferred resources of 20,000 tU both at about 0.02% with 100 ppm cut-off (JORC & NI 43-101 compliant) 30 km southwest of Rossing and 35 km east of Swakopmund. The company is proceeding towards a definitive feasibility study for mining possibly from late 2013. Production of 2000-2500 tU per year for 16 years is envisaged. Capital cost is estimated at $555 million. The alaskite ore is very similar to that at Rossing, but up to 400m deep. However, capital cost is estimated at $555 million, and the economic feasibility is uncertain.

Marenica: In July 2008 West Australian Metals, now re-named Marenica Energy , announced a 13,000 tU inferred resource (JORC-compliant) in the Marenica palaeochannel deposit 30 km north of Areva's Trekkopje. The leases have promising hard rock mineral potential also, in granite-alaskite down to 60 metres. In November 2009 the company announced an Indicated Resource of 16 Mt grading 0.017% U3O8, and an Inferred Resource of 106 Mt grading 0.014% U3O8. Marenica Energy has an 80% interest in the project. In December 2009 Areva agreed to buy a 10.6% stake in the project from Polo Resources PLC.

Australia's Deep Yellow Ltd, through subsidiary Reptile Uranium Namibia, has the high-grade Inca primary uraniferous magnetite deposit at about 200 metres depth and extensive secondary calcrete deposits contained in the Red Sand-Tumas-Oryx-Tubas palaeochannel and associated systems. While the former looks most prospective, Tubas has JORC-compliant inferred resources of 15,000 tU, Tumas has indicated and inferred resources of 3000 tU. Inca is about 10 km south of Etango and 35 km in from the coast, the calcrete deposits stretch over about 40 km south and southeast of it. The company hopes to develop a mine combining ore from Inca with that from Tubas-Red Sand 10 km south of it to produce about 850 tU/yr. The company also has a joint venture with a Namibia subsidiary of Toro Energy for contiguous ELs.

In 2007 Xemplar Energy Corp of Canada announced a new uranium province in the Warmbad area along the Orange River in the south of the country. It is drilling two large mineralized zones similar to Rossing's ore among 14 which outcrop in an area of 40 x 28 km. Resource figures are expected to be released in 2009. The company also has uranium prospects at Engo Valley, Cape Cross and Aus-Garub in Namibia, all being along the coast.

Namibia's identified uranium resources are about 5% of the world's known total. Those recoverable at up to $130/kg are about 275,000 tonnes U. The Reasonably Assured Resources portion of this is 176,000 tU, accessible by open pit mining.

Nuclear power

Namibia's electricity supply of some 3 billion kWh per year is half supplied by South Africa, which faces serious supply constraints itself. A coal-fired plant is planned for Walvis Bay.

The government has committed to a policy position of supplying its own electricity from nuclear power by about 2018. The country faces severe challenges in power supply.

Non-proliferation

Namibia is party to the Nuclear Non-Proliferation Treaty and has had a comprehensive safeguards agreement in force since 1998 and in 2000 signed the Additional Protocol.

Sources:
OECD NEA & IAEA, 2006, Uranium 2005: Resources, Production and Demand
Paladin Resources
UraMin

參考來源:World Nuclear Association

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