By Ryan Grim | HuffingtonPost.com

Just how bad has the coal ash situation gotten in the United States?

So bad that the Department of Homeland Security has told Sen. Barbara Boxer (D-Calif.) that her committee can't publicly disclose the location of coal ash dumps across the country.

The pollution is so toxic, so dangerous, that an enemy of the United States -- or a storm or some other disrupting event -- could easily cause them to spill out and lay waste to any area nearby.

There are 44 sites deemed by the Environmental Protection Agency to be high hazard, but Boxer said she isn't allowed to talk about them other than to senators in the states affected. "There is a huge muzzle on me and my staff," she said.

"Homeland Security and the Army Corps [of Engineers] have decided in the interests of national security they can't make these sites known," she said.

There are several hundred coal ash piles across the nation, she said, all of them unregulated.

"If these coal ash piles were to fail they'd pose a threat to the people nearby," she said. While keeping it from the public, DHS is alerting first responders as to the location of the piles.

"I believe it is essential to let people know," said Boxer, arguing that if people knew what was in their backyard they'd press public officials to clean it up and protect the area. "I think secrecy might lead to inaction...I am pressing on this."

Boxer is sending a letter, she told reporters Friday, to DHS and the Army Corps, pressing for public release of the information and asking for a more thorough explanation and a comparison of this policy of secrecy to policies around Superfund-listed sites and nuclear sites.

"We don't need legislation if they do their job," she said.

A recent coal ash spill in Tennessee devastated the surrounding area, was 100 times worse than the Exxon-Valdez spill, said Boxer, and will cost a billion dollars to clean up.

That one's not secret.