Towering above Lake Michigan north of the Wisconsin border, the Oak Creek coal-fired power plant is one of the largest sources of toxic metals dumped into American waterways.

Only six other power plants nationwide released more arsenic, lead, mercury and other metals into lakes and rivers last year, according to a Chicago Tribune analysis of federal records. On the shores of Lake Michigan, no other polluter comes close.

By now the coal plant’s owner should have dramatically reduced its pollution. In 2015, the U.S. Environmental Protection Agency adopted stringent limits on metals that stick around in the environment and become more dangerous as they move up the food chain.

But President Donald Trump’s political appointees stalled the regulations soon after taking office in 2017, and last week they gutted the Obama-era standards for Oak Creek and other fossil fuel plants. The Trump EPA’s alternative fails to require the most effective treatment methods, pushes back deadlines and exempts many power plants from doing anything at all.