TORONTO (miningweekly.com) – Canadian uranium-miner Cameco is making progress in dewatering and remediating the shaft at its flooded Cigar Lake project, in Saskatchewan, the firm said on Thursday.
The company said it plans to file an updated technical report, including a timeline to production start-up and an updated capital cost estimate, for Cigar Lake by the end of the first quarter.
Crews safely re-entered the main shaft on November 12 and the remediation effort, which is currently focused on refurbishment of the main shaft, is about two-thirds complete. The work involves installing a ladderway in the shaft, replacing mechanical and electrical components and the extension of the in-shaft pumping system.
After the main shaft remediation work is complete, and assuming that dewatering progresses as planned, crews will be able to re-enter and inspect the underground development to assess what additional repairs are needed, Cameco said.
At the same time, they will gather information needed to update the mine plan.
To date, about one half of the total volume of water in the mine has been pumped out and the water level is now down to the 475 metre-level in the main shaft.
The company said it still expects to complete the dewatering and work to secure the underground development between April and October 2010, depending upon the condition of the mine.
Cameco is the operator of the Cigar Lake project, and owns 50%, while Paris-based Areva holds 37%, Idemitsu Canada Resources owns 8% and Tepco Resources owns the remaining 5%.
The large uranium operation was expected to start production as early as 2008, before a rock fall caused a flood in October 2006, forcing the company to halt development.
Cameco received approval to start dewatering the mine in June last year, after successfully testing an underground seal, but was approaching the bottom of shaft one when the mine flooded once again in August.
The firm has since successfully sealed off the area where the leak occured.
The Cigar Lake project contains proven and probable reserves of more than 226,3-million pounds of uranium oxide and is the world's largest undeveloped high-grade uranium deposit, according to Cameco.