Readers Want to Know...

What Happened to the taconite tailings?

In a word: nothing. The taconite tailings, byproducts of extracting low-grade iron from North Shore rocks remain in Lake Superior where they were discarded prior to 1980. It was deemed an impossible effort to remove them from the lake because they are so widely dispersed. After litigation forced Reserve Mining Company to dispose of its tailings in a land-locked basin, the potentially carcinogenic waste ended up just west of Silver Bay at Milepost 7, about five miles from Lake Superior.

The story of how the tailings ended up on land instead of in the lake is called by some, "the longest environmental trial in American history." It goes like this:

Accessible transportation and abundant water prompted Reserve Mining to build a taconite processing plant on the shore of Lake Superior. As iron-rich rocks are crushed and the metal is extracted, about two-thirds of the taconite ore remains as tailings. From 1955 to 1980, permits allowed the company to dump tailings directly into the lake, which happened at a rate of up to 67,000 tons a day. This is more than two times the estimated solid waste produced by New York City during the same period.

In 1969, the Sierra Club, with other groups, filed a suit to force the Minnesota Pollution Control Agency to apply standards set forth in the Water Quality Act of 1965. The resulting legal odyssey lasted through April 1982, pitting governments and citizen organizations against steel companies, Iron Range communities, and the United Steelworkers union.

The dispute became heated by reports that "asbestos-like" fibers released from the tailings had filtered through Western Lake Superior into the municipal water systems of Duluth and surrounding communities. An ensuing cancer scare and federal trial garnered national attention as plaintiffs and defendants considered the effects of the pollution, the socioeconomic consequences of alternative waste sites, and possibly closing an industry on which an entire region depended.

In 1977, Reserve Mining began the $375 million on-land tailings disposal project at Milepost 7, which was completed in 1980 after more political and legal challenges. In 1985, Reserve obtained permission to pump filtered overflow water from the tailings pond back into Lake Superior but the mining operation closed the following year.

The facility reopened on a smaller scale as Northshore Mining in 1989, and still produces taconite pellets. Questions remain about the health and ecological effects of taconite tailings. If deemed safe for commercial use, Northshore Mining might be able to sell their coarse tailings as aggregate. Such sales could offset the company's monitoring costs at Milepost 7; over 100 tailing samples are analyzed for fibers per year at about $1,000 per sample. Prior to the 1975 ruling that forced Reserve Mining to stop dumping taconite tailings into Lake Superior, the tailings were used to construct roads, combat slippery winter driving, and as part of concrete mix.

Sources:
L. Bloomquist, 2003. Taking another Look, Duluth News Tribune online article posted on March 29.

T. Huffman, 2000. Exploring the Legacy of Reserve Mining: What Does the Longest Environmental Trial in History Tell Us About the Meaning of American Environmentalism? J. Policy History 12(3): 339-368.


By Sea Grant Staff
June 2005

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