On Monday, Wisconsin Governor Scott Walker signed legislation ending a nearly two-decade moratorium on gold and silver mining in the state.
The new bill, which goes into effect in six months, opens the door to sulfide mining, which environmentalists oppose due to the risk of acid mine drainage—a process by which acidic substances can leach into waterways, even after mining operations are closed.
Since 1998, Wisconsin law has required that, in order to obtain a mining license, companies must first provide evidence that another sulfide mine in the United States or Canada had operated for at least 10 years and been closed for at least 10 years without any pollution—a strict provision that has effectively prevented any sulfide-mining permits from being issued in the state, which sits on vast deposits of copper, zinc, gold, and silver.
Walker voted to impose the strict requirement in 1998 as a member of the state assembly, but he now argues that advances in technology have made sulfide mining safer. "If there's anywhere in the world that should be able to conduct safe and environmentally sound mining, it should be the Badger State," Walker tweeted on Monday.