The shaft is a 2-compartment, 16-ft-diameter (4.9-m) structure. A double drum, 12-ft Nordberg hoist serves transportation needs. The shaft mucking is accomplished with a Cryderman mucker. Two 700 cu-ft- per-min Ingersoll-Rand compressors supply compressed air requirements. Dynatec Engineering did the design engineering for the headframe and shaft.
Two drifts will be excavated above and below the ore zone, the first at 420 m and the second at 470 m. (For a discussion of mining methods, see accompanying Cigar Lake story.) Current plans call for drifting with an Alpine AM 50 roadheader. Peebles said the roadheader should be powerful and tough enough to drive through the rock, which has an unconfined compressive strength of 11 to 12 MPa. Average orebody thickness is 7 m. The orebody strikes for 2,000 m and varies in width from 25 to 105 m. It is estimated to contain 385 million lb of U3O8 in two distinct sections — a rich main pod in the eastern portion and a lower grade (only 4%) in the western extension. The shaft has been sited 130 m south of the orebody.
On surface, an 84-person camp has been set up. Fortier International is catering the project. Three 1,000-kW Caterpillar generators supply the power. Because of the dangers of radioactive contamination, an elaborate mine water treatment facility designed by Kilborn Engineering has been built.
The shaft sinking and eventual test mining has been budgeted at $50 million to $60 million. By late 1990, test mine results should be in. Peebles said the first method to be tested will be standard raise boring. Undercut- and-fill, blind boring and boxhole boring are also scheduled tests. But should raise boring prove satisfactory, development would begin immediately afterwards, he said.
It is not known yet whether Cigar Lake will have its own mill. Crushed ore could be trucked to the Key Lake mill more than 100 km away (if and when a road is built connecting the two operations). If a mill is built on the site, the total cost of a Cigar Lake mine and mill should be about $300 million. Olav Svela
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