Thomas Evans is the assistant director at the Wisconsin Geologic and Natural History Survey. He joined the 8 0’Clock Buzz on Monday to share his expertise on bedrock in northern Wisconsin. Understanding bedrock content in Wisconsin is crucial when extracting large deposits of any kind of mineral. Most of the rock in Wisconsin that is currently of interest, according to Evans, is a lower grade iron ore. This means 25 to 33 % of the rock formation is usable iron ore. Much of the remaining rock is considered waste. Waste rock causes concern because it has to be managed. If it is improperly dealt with the waste rock can release harmful toxins. Legislation introduced last week allows mining companies to bypass environmental laws in northern Wisconsin that protect fragile ecosystems. Thomas Evans gives a scientific perspective as to what an open pit mine means for Wisconsin.