The McClean Lake mill is one of the most technologically advanced uranium mills in the world and the only facility in the world specifically designed to process high-grade uranium ore without dilution. The mill currently processes ore from the underground Cigar Lake mine under a toll milling agreement. Cigar Lake is located 70 km southwest of McClean Lake and is currently the mill’s sole source of feed.

Cigar Lake is the world’s highest-grade uranium mine, with an average grade of 15.9% U3O8. Mine ownership is 50.025% Cameco Corp., 37.1% AREVA, 7.875% Idemitsu Uranium Exploration Canada, and 5% TEPCO Resources. Cameco is the operator.

Cigar Lake is mined by an innovative jet-boring mining method operated from tunnels in the basement rock below the orebody, using high-pressure water jets to mine out cavities in the ore. A mixture of ore and water is piped away from the cavities to underground processing circuits, where it is ground and thickened and pumped to the surface for transportation to the McClean Lake mill. Production is forecast to reach design capacity of 18 million pounds per year (lb/y) of uranium concentrate by 2018.

The McClean Lake mill has a total production capacity of 24 million lb/y of uranium ore concentrate, providing it with excess capacity to process potential new ore from McClean Lake and other uranium deposits in the future. Denison’s preliminary economic assessment for its Wheeler River project, completed in 2016, contemplates the use of the McClean Lake mill on a toll milling basis to process mine production from Wheeler River’s Gryphon and Phoenix uranium deposits. The Wheeler River project is a joint venture between Denison (60%), Cameco Corp. (30%), and JCU (Canada) Exploration (10%).