TORONTO (miningweekly.com) – Teck Resources may have to curtail operations at its Red Dog zinc mine, in Alaska, after environmental and tribal groups appealed a key permit issued by the US Environmental Protection Agency (EPA).

If the appeal results in permitting delays beyond May, the company will probably halt production at Red Dog in October, it said on Wednesday.

“Production would not be expected to resume until the appeal is resolved and the mine can be restarted, which could take up 18 months unless the appeal is withdrawn,” Teck said.

The groups have filed an appeal against the EPA's renewal of Red Dog's water discharge permit, which was due to come into effect on March 1, and which Teck needs to begin mining the Aqqaluk deposit, which is the next stage of development at Red Dog.

The same groups have already appealed the Alaskan government's decision that the water discharge permit renewal complied with the State's water quality standards.

Until the EPA issues a notice clarifying which provisions of the permit are subject to appeal and therefore stayed, the entire new permit is stayed, Teck said on Wednesday.

The notice is usually issued by the EPA within 30 days of the appeal and the unstayed provisions would then come into effect 30 days after the notice.

Teck said it will not know whether and to what extent access to the Aqqaluk deposit will be affected until the EPA issues its notice.

The current operating plan calls for continuing to mine the main deposit under existing permits until mid-2011, but main deposit ore will eventually need to be blended with higher-grade ore from Aqqaluk to ensure the operation remains economic.

Other State and local permits required for the development of Aqqaluk were received in December, 2009, and the appeal period for those permits has expired.

The Aqqaluk deposit contains 51,6-million tons of reserves, containing 16,7% zinc and 4,4% lead, and represents an estimated 20 years of additional mining at Red Dog.

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