CURRENT STATUS

The Rabbit Lake mill is being converted to treat Collins Bay 'B' ore. The Rabbit Lake ore has been virtually exhausted and the Rabbit Lake pit will be used as an integral part of the tailings disposal system. Rabbit Lake has operated for over ten years and has produced 18 000 t uranium. With current reserves in the Collins Bay area the mill should operate well into the next century.

Amok's operation at Cluff Lake is now well into Phase 2. The high grade ore was mined, milled and treated in a span of four years. Phase 2 has a mill capacity of 800 t/d compared with 25 t/d in Phase 1. Phase 2 is treating lower grade ore. Current reserves indicate operations, based on the remaining ore bodies, for at least a decade.

Key Lake had a few teething troubles. Key Lake installed a semi-autogenous grinding system and this is working well. As mentioned earlier, sand filters and IX were added to improve the economics of effluent treatment. Winter conditions complicated the tailings disposal system so that a revised strategy utilized winter ponding and sub-aerial dispersion during the summer. Key Lake is working very

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well after its first year. At 4000 t uranium per year Key Lake is Canada's largest uranium producer.

As can be seen, these Saskatchewan uranium plants have significantly changed the Canadian production capability. Recent discoveries show promise of several more deposits in the area with significant reserves. These too will have unique problems related to recovery. These new deposits will challenge the mining engineer as much as the metallurgist. They occur under lakes, in incompetent rock and with high grades and may require underground mining technology. The challenges of Cluff Lake, Key Lake and Collins Bay may pale in comparison.

REFERENCES

[1 ] Uranium in Canada, 1984 Assessment of Supply and Requirements, Department of Energy, Mines and Resources, Ottawa, Canada (1985).

[2] BAYDA, E.D., GROOME, A.J., McCALLUM, K.J., The Cluff Lake Board of Inquiry, Saskatchewan Department of the Environment (May 1978).

[3] CARINO, A.B., Uranium recovery at the Rabbit Lake operation of Gulf Minerals Canada Limited, CIM (Can. Inst. Min. Metall.) Bull. 72 806 (Jun. 1979) 162-166.

[4] McMILLAN, R.H., Genetic aspects of classification of important Canadian uranium deposits, CIM (Can. Inst. Min. Metall.) Bull. 91 800 (Dec. 1978) 61-67.

[5] Key Lake Mining Corporation and Sherritt Gordon Mines Limited, "The Key Lake uranium process', 19th Annual Conference of Metallurgists, Canadian Institute of Minimg and Metallurgy, Halifax, Nova Scotia, Aug. 1980.

[6] MORRISH, A., "The future of the Rabbit Lake Mill of Gulf Minerals Canada Limited", Proc, Canadian Uranium Producers Metallurgical Committee (CUPMC), Department of Energy, Mines and Resources, Ottawa, Canada, Rep. ERP/MSL 82-42 (TR) (1982).

[7] SWIDER, R.C., "Development of the strong acid strip process for Eldor Mines", Proc.

Canadian Mineral Processors Meeting, Toronto, 1983.

[8] FOURNIER, P., "Milling high grade uranium ore at Cluff Lake, Saskatchewan", Proc, Canadian Uranium Procedures Metallurgical Committee (CUPMC), Department of Energy, Mines and Resources, Ottawa, Canada, Rep. ERP/MSL 83-39 (TR) (1983) 1-24.

[9] SCHNELL, H., FOURNIER, P., "Update of the Cluff Mining Phase 2 Expansion and Interim Operation", Proc., Canadian Uranium Producers Metallurgical Committee (CUPMC), Department of Energy, Mines and Resources, Ottawa, Canada (1984).

[10] NEVEN, M., ROSNER, B., "The Key Lake flow sheet", Proc., Canadian Uranium Producers Metallurgical Committee (CUPMC), Department of Energy, Mines and Resources, Ottawa, Canada, Rep. ERP/MSL 80-158 (TR)(1980).

[11] Key Lake: 1984 Annual Report to the Atomic Energy Control Board, Ottawa, Canada.

DISCUSSION

W. FLOTER: Several important uranium deposits in Canada, like Cluff Lake Midwest, Collins Bay and Key Lake, were found in the same general area and at about the same time. Yet, they all have different process flow sheets and they are

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all working efficiently and at a profit. Why is there not a 'Saskatchewan flow sheet' common to all these deposits?

M.C. CAMPBELL: There is no one process route that can be definitely said to be superior to the others. This is a matter of judgement and of the experience of the people involved in the project. It may not even be important to judge the superior-ity of one scheme over another. You design a process that will be efficient and profitable and once you believe you are right and have made a decision you do not want to change that decision.

K.H. TREUE: Based on your 30 years of experience with uranium mining and milling in Saskatchewan, what has been, in your view, the main change regarding environmental regulations and what has been the economic impact of these regulations?

M.C. CAMPBELL: The main change is that society has become more aware of the need to control effluents from the mines and plants and uranium producers are being forced to meet more stringent standards before they can even get a licence.

When the early plants started in the 1950s one had to have a mining licence but there was no environmental licence as such. You treated the effluents as best as you could and the rest went into the local watercourse. Today, effluents are often required to meet drinking water standards. The cost of doing this is quite sub-stantial. It probably represents 10% or more of the cost of the plant. But in some provinces you are not allowed to operate at all. The Bayda Commission did not oppose uranium mining and milling in Saskatchewan. British Columbia and Newfoundland have ruled against uranium exploration and development. British Columbia imposed a one year moratorium and Newfoundland a ten year moratorium.

In Newfoundland the government inquiry asked consultants if they thought that in ten years uranium mining and milling could have better environmental controls.

They said that they thought so and the authorities said: "That's very good. Thank you very much. We will wait ten years".

K.H. TREUE: Are the tailings dams at Key Lake regarded as permanent repositories or just as an interim solution?

M.C. CAMPBELL: They were designed as permanent repositories, they have been approved as such by the Atomic Energy Control Board and they are being operated on that basis. They probably are the best tailings dams installed and operating right now.

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