The EPA has been under assault from the GOP for the past year, and this has led to some uncomfortable rollbacks and compromises. The Administration’s cancellation of new ozone standards was particularly galling. But today, the EPA came through with new rules on mercury and air toxics that will deliver massive public health benefits, in addition to reducing greenhouse gas emissions. Congress called for new mercury and air toxics standards 21 years ago, so this has been a long time coming.

The rules require coal- and oil-fired power plants to lower emissions of 84 different toxic chemicals to levels no higher than those emitted by the cleanest 12% of plants. Companies have three years to achieve the standards, and EPA has made clear a fourth year and perhaps even more time are also available to them.

“We’re delighted,” says Janice Nolen of the American Lung Association. “After waiting 21 years, it looks like we may actually have a rule that will help to save 11,000 lives a year and reduce exposure all across the country to a bunch of really toxic substances.”

“It’s hard to overstate the significance of this rule,” says John Walke of the Natural Resources Defense Council, an environmental group. “This is a generational achievement, that mark’s America cleaning up dirty power plants once and for all.”

David Roberts at Grist also praises the rule. He refers to it as similar to getting lead out of gasoline. It will likely lead to the mothballing of dozens of the dirtiest coal plants in the country, most of which are well over 50 years old and out of compliance even with the original Clean Air Act of 1970 (they were grandfathered in back then). The allegedly burdensome costs of upgrades and factory construction are massively outweighed by the public health savings, to say nothing of the human lives saved by reducing toxics in the air. And blackouts will not result from the rules, either.

And this is not something subject to a market-based trading solution, either:

There’s no trading system for mercury like there is for SO2 (the Bush administration tried to set one up, but the court struck it down). There are no short-cuts either. Every plant that’s out of compliance has to install the “maximum available control technology.” There is some flexibility — more than industry admits — but there’s no getting around the fact that this is going to be an expensive rule. It’s going to kick off a huge wave of coal-plant retirements and investments in pollution-control technology. That is, despite what conservatives say, a good thing, since the public-health benefits will be far greater than the costs. Every country on earth is modernizing its electric fleet. Even China’s ahead of us. These crappy old plants are an embarrassment and good riddance to them.

The industry has three years to comply, and at that point we will have eliminated many of the sources of toxic air pollution from power plants in the US. You’re talking about preventing 11,000 preventable deaths, 4,700 heart attacks and 130,000 cases of childhood asthma every year. That’s something to be proud of.