MINNEAPOLIS (AP) — Three companies submitted bids to explore and mine for copper, nickel and other metals in Minnesota’s latest mineral rights auction, the Department of Natural Resources said Wednesday.

Duluth Metals LLC bid on nine parcels about six to nine miles northwest of Silver Bay in Lake County; Encampment Minerals Inc. bid on 21 parcels about six to 12 miles south of Hoyt Lakes; and MMG USA Exploration LLC bid on one parcel about five miles southeast of McGregor in Aitkin County, said Kathy Lewis, assistant director of the DNR’s Division of Lands and Minerals. About 9,500 acres are involved.

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Duluth Metals is the parent company of Twin Metals, which is developing plans for a copper-nickel-precious metals underground mine near Ely. Encampment Minerals also been long active in prospecting in northeastern Minnesota. The sites it bid on are a few miles away from the proposed PolyMet open pit copper-nickel-precious metals mine near Hoyt Lakes. MMG is a Colorado-based unit of an Australian company that’s relatively new to prospecting in Minnesota, Lewis said.

Such lease auctions attracted little attention before the boom in exploration for what are believed to be vast untapped reserves of nonferrous metals south and east of Minnesota’s Iron Range. The DNR’s last lease auction, mostly for land between Ely and Isabella, prompted an angry outcry from residents and landowners that delayed the process for seven months before those leases were approved in May.

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Opposition already has surfaced to the new leases. A group of citizens petitioned the DNR late last month to prepare an environmental assessment worksheet before awarding the leases, a study that could delay the process again. Lewis said the DNR is still preparing its response and has until early November to reply.

The DNR will review the new bids, then notify landowners who might be affected, and then submit the package for approval to the state’s Executive Council. It is next scheduled to meet Dec. 6, Lewis said.

“I’m sure there are going to be some surprised private landowners,” said Betsy Daub, policy director of the Friends of the Boundary Waters Wilderness, a group critical of mining plans. She said the state’s process for awarding mineral rights lacks transparency and makes it very difficult for average Minnesotans to get details about what’s happening.

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