To: Wisconsin Environmental Law Journal

From: Al Gedicks, Dave Blouin and Zoltan Grossman

Exxon/Rio Algom's proposed Crandon metallic sulfide mine continues to be one of the most controversial environmental issues in Wisconsin. Never before has a sulfide mine been cleaned up completely, and because of the threat of the mine, American Rivers (a national river protection organization) has named the Wolf River one of the nation's most threatened waterways.

In 1986, after a decade of strong local opposition, Exxon Minerals withdrew its application to construct a large underground mine next to the Mole Lake Sokaogon Chippewa reservation in northeastern Wisconsin. Seven years later, Exxon and Canada-based Rio Algom formed the Crandon Mining Company (CMC) and announced their intention to extract 55 million tons of zinc-copper sulfide ore at the site over 28 years, enough to yield more than $4 billion worth of zinc and copper. But the latest efforts of the mining companies to sell local communities on the project have met significant opposition from local citizens, environmental organizations, Native American nations and sportfishing groups.

Situated at the headwaters of the Wolf River in Forest County, the proposed mine is the largest of a series of metallic sulfide deposits planned for development in northern Wisconsin. Along with the currently operating Ladysmith mine on the banks of the Flambeau River in Rusk County, the Crandon mine would open a new mining district across northern Wisconsin, located near the headwaters of a number of our major rivers.

The Crandon Mine: A Proposal for Wisconsin's Largest Toxic Waste Dump

The proposed Crandon mine would generate an estimated 44 million tons of waste - the weight of eight Great Pyramids of Egypt. Half of the waste--rocky "coarse tailings" would be dumped to fill the mine shafts. The other half of the waste--powdery "fine tailings"--would be dumped into a waste pond about 90 feet tall and covering 355 acres. At a size of about 350 football fields, it would be the largest toxic waste dump in Wisconsin history. The water table beneath this dump is as close as 15 feet down. Although the waste dump will have a liner over the top and one beneath it, it is well known that these liners inevitably leak. Basically, we're talking about a big plastic "baggie" with no proven track record that must isolate the waste for centuries. The question then, isn't whether it will leak, but how soon and what will happen when it does. Unfortunately, we are facing long-term risks of future contamination. A geological study of the Crandon site concluded that areas such as that of the proposed waste dump are "not good for disposal of waste materials owing to the probability of leachate (acid mine drainage) percolation to the water table."

The computer "modeling" (or predictions) done on the liner and tailings does not extend beyond a few hundred years. But the Department of Interior's Office of Environmental Project Review has warned that water pollution from mining wastes could last for 9,000 years. According to Jerry Goodrich, recently retired president of the Crandon Mining Company, the plastic liner underneath the toxic mine waste will dissolve