Update on the containment of leach tank failure
(11 December 2013)

Rössing Uranium Mine has commissioned a full investigation into a leach tank failure at its mine.

One of 12 leach tanks in the mine's processing plant failed at around 18:30 on Tuesday, 3 December 2013, causing a leachate spill which was fully contained onsite and without any impact to the environment.

The leachate is a mixture of crushed ore, water, acid, manganese and iron. Its uranium content is as in the mined ore (about 300 ppm), but diluted with the liquids, so radioactivity is significantly less than that of mined ore.

The area where the tank failed has since been demarcated and made safe to prevent unauthorised entry.

Apart from minor first aid administered at the scene, no employees sustained injuries or came into contact with the material during or after the incident.

The leachate was channelled in existing engineered trenches into an overflow sump within the area's containment systems, from where it will be recycled in the processing plant.

Following the incident, regular measurements by the mine's Radiation Safety section have shown radiation dose levels have not increased and have remained well within safe levels.

Monitoring will continue to ensure exposures to the clean-up team will not exceed the normal occupational exposures in the area.

Rössing remains at all times committed to the health and safety of the employees and the community and the protection of the environment.

Rössing is working with the relevant regulatory authorities in Namibia in the management of the incident.

The mine's milling operation was stopped after the spill, but is expected to restart after restoration work has been undertaken. A restoration schedule is currently being developed.

Production in the other areas of the mine has not been affected and continues as usual.

The cost of the restoration work as well as impacts to the mine's production and financial results are yet to be determined.

Leaching is a step in the production of uranium oxide where the milled ore is leached in a sulphuric acid solution.

Visit the Rössing website for information on the operations: www.rossing.com

Werner Duvenhage
Managing Director
Rössing Uranium Limited