Between 1991 and 2011 Flambeau Mining Company (FMC) was required to test walleye in the Flambeau River for heavy metal accumulation, both upstream and downstream of the Flambeau Mine site. Before the mine was built in 1993, the upstream walleye had higher levels of copper and zinc in their liver tissue than the downstream fish. That reversed in 1996 (at the height of mining); for the next ten years (1996‐2006) higher levels of copper and zinc were measured in the downstream fish. A graph of the 2005 data is shown below.

Flambeau Mine Walleye‐Ometer

082 Walleye Ometer

What the future holds for the walleye in the Flambeau River is unknown. Polluted groundwater from the Flambeau Mine site continues to enter the river through fractured bedrock, but, with the end of mandatory walleye testing in 2011, FMC is now “off the hook.”

To see the walleye data submitted by Flambeau Mining Company to the Wisconsin Department of Natural Resources and various reports evaluating the data, click on the below links: