On Oct. 31, a landslide at the Wisconsin-based We Energies Oak Creek Power Plant sent piles of coal ash, along with dredging equipment and debris, into Lake Michigan. Thankfully, there were no injuries, but the incident is reminiscent of the disastrous 2008 coal ash spill in Kingston, TN – where a failed impoundment released 5.4 million cubic yards of coal ash that buried a community and severely contaminated a nearby river – and raises concerns about how to regulate the storage and disposal of coal ash.

Coal ash is a combustion byproduct that can contain arsenic, lead, chromium, and other heavy metals, all of which pose significant health threats to humans. Because the toxins in coal ash can leach from landfills and surface impoundments into rivers, lakes, and streams, there are dangers in handling coal ash, even if it is recycled for beneficial uses. According to the Milwaukee Journal Sentinel, We Energies reported coal ash had not been used as a fill material near the site in decades. But Cheryl Nenn, of Milwaukee Riverkeeper, said that the group wants "the environmental agencies and We Energies to study how much of that coal ash, if any, went into Lake Michigan because it does pose such a threat to human health and the environment." Investigators from Wisconsin’s Department of Natural Resources are examining potential contributing factors to the bluff collapse and subsequent mudslide, including an unlined storm water retention pond near the coal ash, water seepage from the pond into the coal ash, and construction activity, reported the Journal Sentinel.

Calls for greater federal regulation and oversight of coal ash followed the Tennessee disaster in 2008, but powerful industry opposition has obstructed efforts to impose greater oversight. And last month, a bill passed the House that would limit federal authority and require the EPA to defer the regulation of coal ash to states. Monday's coal ash spill in Wisconsin serves as a strong reminder of the potential dangers of coal ash and the need for consistent nationwide standards, especially given the poor safety ratings reported for coal ash impoundments in many states.

The U.S. Environmental Protection Agency (EPA) proposed two options for regulating coal ash in 2010. The first option would designate coal ash as a hazardous waste, requiring special handling, transportation, and disposal, and would closely monitor any potential reuse. The second would regulate coal ash in a way used to control less toxic wastes such as household garbage – an option that would limit EPA's responsibility and authority over coal ash management. Both regulatory options would require that surface impoundments of coal ash have protective liners, mandate groundwater monitoring for landfills, and provide for corrective action where contamination is found (though the corrective action requirements are more extensive under the first option). Already delayed, agency standards could be undermined by current legislative efforts.

The Coal Residuals Reuse and Management Act (H.R. 2273) passed in the House Oct. 14 by a vote of 267-144 and received votes of support from every Wisconsin representative. But the bill also incurred criticism from Democrats on the Energy and Commerce Committee and environmental groups. Earthjustice condemned the House for putting "the interests of corporate polluters ahead of the American public," and is urging citizens to take action against the Senate companion bill, S. 1751.

S. 1751 was introduced by Sens. John Hoeven (R-ND) and Kent Conrad (D-ND), despite the fact that coal ash ponds in their state recently received "poor" inspection ratings. EPA is releasing contractor reports assessing the structural integrity of impoundments containing coal ash at coal-fired power plants across the country. So far, a number of impoundments have been given both a "significant" potential hazard rating and a "poor" inspection report, including three in North Dakota.

All of this begs the question: How many spills, buried towns, and poisoned drinking water supplies will it take before Congress and the industry relent and allow the EPA to do its job to protect the American people from toxic coal ash?