Cameco Corporation has a new baby on the way - otherwise known as the Millennium Deposit. Millennium is a basement-hosted uranium deposit nestled 35 kilometres north of Key Lake in northern Saskatchewan and is currently in the feasibility phase. It sits on the Cree Extension exploration lease, which is a joint venture between Cameco, JCU, AREVA, and UEM (Cameco being the project manager). Drilling in 2000 led to the initial discovery of mineralization. The pre-feasibility study was completed in September 2006 and the feasibility study is expected to be complete in early 2008. After a lengthy conversation with senior geotechnical engineer James Hatley, I now have a better idea about how Cameco and its partners plan to raise this new addition.
At the moment, facilities at the Millennium deposit are minimal. With only the Cree Extension exploration camp and a winter road in place, there’s plenty of work to keep the crew busy. The plan is to put in infrastructure, power, a water treatment plant, service shaft, ventilation shaft, administrative buildings, surface equipment shop, emergency generators, a concrete batch plant, and a water treatment facility, which will include monitoring ponds and an emergency water pond. They will also have a clean waste pad, an ore pad, and an acid-generating rock pad, which will, of course, be lined.
The sinking of two concrete-lined shafts (to depths of 755 and 630 metres) is anticipated, and the mine will consist of two main levels and five sublevels located at 20-metre vertical intervals. The shaft sinking is expected to begin in 2012 and with equipping will probably take about two and a half years. The mineralization is located in dry basement rock but the shafts traverse water-bearing sandstone. Blasthole stoping is the planned mining method.
Both cemented and uncemented aggregate backfill will be used to fill the stopes, while crushed development waste rock will be used for backfill. This aggregate will be delivered underground using one of two drop pipes located in the service shaft, although backskipping is also being investigated. Hatley added that “current plans are to build a 10,000 m3 per day conventional water treatment plant to support shaft sinking and lateral development. This plant may be supplemented later by a reverse osmosis plant capable of treating and discharging up to 80 per cent of the feed water. Remaining water will be treated by the conventional treatment plant. A supplemental emergency water treatment circuit capable of treating an additional 20,000 m3 per day of water is planned."
Before any site construction begins (targeted for 2012), a 24 kilometre access road will be constructed in 2011. Power will be provided from the existing grid with a new power line running parallel along the access road to the mine. First ore development is expected to begin in 2016 with an annual production of six to seven million pounds U3O8. Because ore will not be milled onsite, they’ve been looking at their options. Their most likely choice will be Key Lake, about 45 kilometres from the site. They will probably ship about 500 tonnes daily in haulage. All in all, the Millennium deposit has an expected mine life of about eight years, and boasts an indicated resource of 37.5 million pounds, and inferred resources of 9.7 million pounds U3O8 based on the September 2006 feasibility study.