Cameco Corp has announced that remediation work is under way at Cigar Lake uranium project in northern Saskatchewan following a water inflow that flooded the underground development.

Currently, Cameco is proceeding with the most conventional option to restore the underground workings in phases. The first phase includes surface drilling holes down to the access tunnel at the 465 metre level in the vicinity of the source of the inflow using oil field rigs. Concrete will be pumped through the drill holes into the tunnel to create a plug downstream from where the rockfall and inflow occurred to seal the inflow. Once the plug has solidified, it will be grouted by pumping cement under high pressure into cracks in the rock and concrete mass to seal them off. Subsequently, the area of the rockfall itself will be filled with grout. Progress will depend on the successful completion of each step of the plan for phase one. Phase one is already underway and is anticipated to take at least 60 days, based upon current plans.

Detailed planning is now also under way for the next phase that includes pumping the water out of the mine, verifying the integrity of the plug and the mine workings, restoring underground pumping capacity and ventilation systems and assessing and repairing the bulkhead doors.

Planning continues for subsequent phases that include ground freezing in the area of the inflow, restoring other underground areas and resumption of mine development.

Regulatory approval is required for each phase of the remediation plan.

Work on surface facilities, including water treatment ponds, earth works and an electrical substation, continues.

The Cigar Lake project is a joint venture 50% owned by Cameco, Areva Resources holds 37%, Idemitsu Uranium Exploration has 8% and TEPCO Resources 5%.

Revised capital cost estimates and timelines for the project, which has already been delayed by more than six months from initial estimates following an earlier water inflow, are being developed and are expected to be available in February 2007.

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