F ILE - In this Monday, Dec. 29, 2008 file image provided by Greenpeace, coal ash slurry left behind in a containment pond near the Tennessee Valley Authority's Kingston Fossil Plant. (Wade Payne/AP)

MITCH MCCONNELL (R-Ky.) often decries President Obama’s “war on coal,” promising to attack Environmental Protection Agency regulations when he’s in charge of the Senate. In reality, the Obama EPA is only slowly beginning to deal with the true costs of burning huge amounts of an exceptionally dirty fuel. For example, the EPA’s latest move to regulate huge accumulations of “coal ash” is, if anything, too modest.

The country consumes about 800 million tons of coal each year, the EPA reports. Thankfully, not all of it goes up and out of the smokestack. Some material stays inside plants and boilers, and some gets trapped on its way up. Collectively, these leftovers are coal ash, a messy melange containing mercury, cadmium, arsenic and heavy metals. Coal-plant operators produce around 110 million tons of this waste every year, disposing of it either in on-site landfills or in off-site impoundments, some of them extremely large.

In the past decade, two coal ash pits saw major spills — one in Tennessee in 2008 and one in North Carolina in 2014 — that fouled rivers and endangered people and wildlife. Environmentalists report dozens more instances of air or water contamination from the more than 1,000 coal ash disposal sites around the country, and the EPA has confirmed many of those cases.

Even so, there have been no federal regulations on coal ash disposal — until now. The EPA issued a final rule last month that will set minimum standards on waste sites. Companies will have to meet engineering and site requirements designed to protect water supplies and air quality. They will have to line new pits to prevent seepage. They will have to monitor local water quality. And they will have to release more information to the public. Waste sites that can’t comply will have to close.

Or at least that’s the idea. Environmental activists warn that the EPA declined to classify coal ash as hazardous waste, a designation that would have triggered stricter federal oversight. Instead, coal ash is officially “solid waste.” Among other things, the EPA is largely leaving enforcement to the states, which have been the only overseers before now, though private citizens and environmental groups will be able to sue to demand adherence to the rules. The regulations leave room for extremely lengthy delays in some areas of compliance. They also don’t touch many closed waste sites. Industry groups were strikingly calm in reaction to the regulations’ release.

Though there’s room for tweaking, the rules likely won’t be fully revised anytime soon. Federal officials should nevertheless keep wary eyes on coal ash disposal sites and the state regulators responsible for them, particularly in places where local overseers are close with coal companies. The Obama administration has taken a step in the right direction. It’s better to have basic federal safety and reporting rules than none at all. Most likely, however, the EPA will need to go further.