Dominion Begins Processing Ore


The Dominion project has significant infrastructure in place, including a relatively new
CIL gold-processing plant that has been incorporated into the new processing complex.

sxr Uranium One reported on March 1, 2007, that its Dominion uranium project near Klerksdorp, South Africa, had begun processing underground ore, following successful hot commissioning of the atmospheric leach circuit at the Dominion mill. The new plant also includes a pressure leach circuit incorporating two autoclaves that will be commissioned sequentially later in the year. The first autoclave is expected to be ready for hot commissioning during April, the second during August. Each of the autoclave lines will have capacity to process 100,000 mt/m.

Dominion is a brownfields project previously owned and operated by Anglo American. Gold has been produced in the district since the 1880s, and uranium, along with gold, has been produced more recently. The project has significant infrastructure in place, including a relatively new CIL gold-processing plant that has been incorporated into the new processing complex. Startup capital costs are budgeted at $152 million.

Plant capacity will initially exceed mined ore production, and the excess capacity will be utilized to process uranium and gold bearing slime from the Dominion dump resource. Test work has shown that good recoveries are obtainable from the slime material, and an 80,000-mt/m hydraulic sluicing facility has been commissioned to supplement production from underground. The project is designed to ramp up to an average production of 3.8 million lb/y of U3O8 by 2011. Probable reserves total 31.3 million lb of U3O8.

The Dominion project’s gold and uranium mineralization is typical of such mineralization encountered throughout the Witwatersrand basin, occurring in coarse-grained sedimentary units forming extensive reefs that range from a few centimeters to a few meters in thickness. The mineralization is stratabound, and sedimentological features such as channelization exert strong local controls. Adjacent fine-grained sedimentary units are typically barren.

The mine has been divided into two operating areas, the Rietkuil and Dominion sections. Phase I of the project contemplates mining from surface to a depth of about 500 m, initially using two trackless declines on the Dominion section and one trackless decline on the Rietkuil section. All declines and footwall roadways are being developed using mechanized loading and hauling. Mining on the reef horizon applies traditional South African breast mining methods, with face cleaning using scraper winches or water jetting. Haul trucks used during development will be used to transport ore loaded from stope chutes to surface via footwall roadways and main access declines.