Don't Relax the Rules on Coal Ash

When you think of pollution from coal-fired power plants, you may envision dark soot puffing out of tall smokestacks, peppering the air and making it harder for people to breathe. But since technology has eliminated much of this airborne pollution, what's worse for the environment now is coal ash, a sludge that pours from U.S. power plants at the rate of more than 100 million tons each year.

In 2015, the Environmental Protection Agency confronted the problem by imposing two new rules for coal ash disposal. Earlier this month, EPA chief Scott Pruitt took a step backward, postponing some of the rules' provisions while he reconsiders them. There's reason to worry that he will ultimately allow power plants to return to unsafe disposal practices.