Crandon mine

Crandon mine was a mine proposed for northeastern Wisconsin, USA. It was to be situated near the town of Crandon and the Mole Lake Ojibwe Reservation in Forest County. The mine was the center of a multi-decade political and regulatory battle between environmentalists, American Indian tribes, sportfishing groups, and the State of Wisconsin and several large mining corporations. The purchase of the mine site in 2003 by the Sokaogon Ojibwe and Forest County Potawatomi marked a major victory for the tribes and environmental activists, and raised questions about the future of mining, economics, and tribal power in Wisconsin.

The Crandon site was the location of one of several deposits of metallic sulfide ore found in northern Wisconsin during the 1970s, and its estimated 60 million tons of copper, zinc and other metallic sulfides was thought to hold the highest potential for profit. Three sites in all were proposed for digging. From the outset, environmental groups opposed the process of extracting metals from the sulfide ore, which if not properly handled may create sulfuric acid as a waste product. Each of the three sites was sufficiently close to an Ojibwe reservation to attract tribal opposition as well.

As news of the proposed mine spread, many environmental groups such as the Sierra Club sprang into action. Other groups formed in opposition to the mine, such as Protectors of the Wolf River (POW’R), and eventually worked with Gedicks on coordinating environmentalist efforts. Among their fears was the potential for acid mine drainage that results from sulfides mixing with air or water. Sulfide rock can produce high levels of poisonous heavy metals such as mercury, lead, zinc, arsenic, copper, and cadmium. This process is the single largest cause of negative environmental impact resulting from mining. This was of particular concern because the proposed mining area was in extremely close proximity to the Wolf River. Furthermore, environmentalists were not pleased about the discharge into that river, which would contain heavy metals. The estimate of the density of these heavy metals varied range depending on who made the estimation. Lastly, there was a concern about the amount of waste that the mine would create and how it would be contained from adversely affecting the natural world. Over its lifetime of production, the mine would generate about 44 million tons of waste. Half would be rocky “coarse tailings”, which would be dumped to fill the mine shafts, while the other half would be powdery “fine tailings”, which would be dumped into a waste pond equivalent to the size of 340 football fields with a plastic liner separating the tailings from the environment.

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