The collapse of a massive cliff next to a power plant in Oak Creek, Wis., sent coal ash and other debris rolling across a road, onto the shoreline and into the waters of Lake Michigan Monday, according to an Oct. 31 report in the Milwaukee Journal Sentinel.

No one was injured in the incident, but it raises concerns Creative Loafing has been pointing out for years with respect to Charlotte's own coal-ash ponds. To sum up: There are four coal-ash ponds near Charlotte, all on the edge of the Catawba River. Duke Energy, headquartered in Charlotte, owns all of the coal-ash ponds, which are unlined — meaning there is nothing to prevent them from soaking into area groundwater, which they do.

The two ponds of most concern to Charlotteans are about 12 miles from center city — so close you can see Duke's new Voltron building from the corner. The state has deemed them high-hazard ponds. And they're huge — one is about 40 acres, the other about 19, and both are deep enough to swallow telephone poles without a trace. In fact, you could stack two of them end-to-end in the oldest and largest pond, and you'd only see a little of the top pole bobbing above the surface.

The two ponds at Riverbend drain into Mountain Island Lake, the main drinking-water reservoir for Charlotte, although Mount Holly and Gastonia also pull water from the lake.

We're reminding you of this because what happened Monday in Wisconsin — which we'll let Rachel Maddow show you in the clip below — is sobering.

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Unfortunately, spills aren't horribly uncommon, though the famous one is the TVA disaster, in which about a billion gallons of coal-ash sludge broke through an earthen dam, polluted two rivers and covered about 300 acres, pushing homes off their foundations (among other destructive and devastating things) a couple days before Christmas in 2008.

The U.S. Environmental Protection Agency promised to regulate coal ash — America's second-largest waste stream — after the TVA disaster and about 30 years of considering doing so. But, they haven't. Still. Instead, we now have a Congress working to block the regulation (reminder: it's a regulation that hasn't been enacted yet) with a bill that has already passed the U.S. House of Representatives and is now waiting on the Senate.

As we reported in September:

The EPA estimates that nationally it will cost $20.3 billion a year to regulate coal ash as a hazardous waste and $8.1 billion to regulate it as non-hazardous. The agency also estimates this regulation will save $290 billion annually in health-care costs.

Never mind the health-care savings, though. The coal industry, and companies incorporating coal-ash into their products, scream "stigma." While the companies can't point to any specifics, they're concerned that any regulation at all will make coal ash less attractive to their customers.

According to Culbert, Duke Energy brought in $2 million in 2010 from sales of coal ash — the dry ash, not the gunk in Riverbend's ponds. "Beneficial reuse also benefits the company because we don't have to dispose of the material," she said. "If you add revenues and savings, the benefit to the company was more than $30 million" last year.

That may explain why, according to OpenSecrets.org, Progress and Duke share the No. 1 spot for the most mentions of "coal ash" — 56 combined — in federal lobbying documents. It also may explain why the amount of lobbying money both companies spent spiked last year. If the two merge, it will be the country's largest energy company, which means power in Washington.

We should point out that there's a difference between wet ash — the stuff in the four ponds around Charlotte — and dry ash, which power companies can sell. Dry ash can be used in products like concrete and asphalt, and actually makes those products stronger. Wet ash can't do anything — but pollute.

The EPA encourages use of dry ash in its proposed regulation. In fact, the wording is, "EPA continues to strongly support the safe and protective beneficial use" of coal-ash residuals.

Here's why: It's better to reuse coal ash than store it in ponds. Power companies make tens of millions of dollars selling their coal waste, manufactures get a cheap ingredient and consumers get a better product (ideally) — emphasis on the word "cheap." Because there's so much coal ash, its price is low. That's what helped the industry surmount the so-called "stigma" it faced in the 1970s when coal ash was called "coal trash." The market hiccuped briefly back then, but because the substance is so inexpensive, it quickly went back to using dry ash in products.

Wet ash is another thing entirely, and that's the stuff we're concerned about in Charlotte. Wet ash is what's sitting in those giant holding ponds and can't be reused in products like concrete or asphalt. What's more: we know that it's draining into the area's drinking water.

Federal legislators don't seem to understand the difference, even though the EPA supports the reuse of dry ash. Judging by the bill in legislators' hands, it appears they'd prefer not to regulate coal ash at all, even though it's clear that coal ash is impacting communities across the country.

Beyond that, according to a recent study by Tufts University, it's estimated that more than 28,000 jobs will be created nationwide if coal ash is regulated, since ponds and power companies will have to hire people to help get facilities in compliance.

Meanwhile, the EPA's list of high-hazard ponds is growing.

To be clear, the EPA and Duke Energy say not to worry about the ponds around Charlotte. They aren't in danger of collapsing. Not that the EPA warned anyone about the other collapses — the 10 or so that have happened across the country with little media attention and virtually no regulation or consequences to the companies involved.

Further reading:
S.1751 - Coal Residuals Reuse and Management Act — OpenCongress.org
Is coal ash poisoning Charlotte-area drinking water? — Creative Loafing cover story
Government oversight remains 'grossly inadequate' in coal-ash waste control — Creative Loafing cover story