Cameco’s Rabbit Lake uranium operation in Canada has resumed normal mining activities, well ahead of schedule, after sealing off the source of a water inflow. In late November 2007, Cameco’s Rabbit Lake underground mine experienced increased water inflow and mining was suspended. Cameco constructed and poured four concrete bulkheads in the first two weeks following the start of this event and has since been grout sealing these bulkheads and the surrounding rock while waiting for the concrete to cure.

At the same time, the site crews determined to locate the source of the water inflow and seal it permanently. An old exploration drill hole was identified as the potential source early on and Cameco used various techniques to locate and verify it. Crews confirmed the source of the mine water inflow by injecting a dye into the drill hole. Then they successfully plugged the hole by installing an inflatable packer in the hole. Mining activities were then able to resume. Cameco will install a permanent plug and grout a substantial length of the drill hole with cement to replace the inflatable packer in the next couple of weeks.

Crews are also currently carrying out a grout sealing procedure on all four bulkheads. They continue to complete the bulkhead installation, primarily as a precautionary measure, since plugging of the exploration drill hole has effectively stopped the source of the increased water inflow and will therefore be the main solution.

“Cameco employees attacked the inflow in two different ways and their success in staunching the water well ahead of schedule is a testament to their dedication, expertise and innovative thinking,” said Jerry Grandey, Cameco’s president and CEO. “All of this was done with full attention to risk evaluation and personnel safety.”

The company reports that it will provide the 2008 production estimate for Rabbit Lake when it issues year end financial results. Cameco, with its head office in Saskatoon, Saskatchewan, is the world’s largest uranium producer.