The Coal Ash Project

Duke Energy's Poisoned Power

How the giant utility's bad science – and friends in high places – hide the poisoning of North Carolina's drinking water by Duke's coal ash

William Busa, Coleman Blake, Elaine McVey, Dylan Wilson
7 April 2016

orth Carolina's Coal Ash Management Act requires the closure of toxic coal ash dumps operated across the state by the giant electric utility, Duke Energy — dumps which have poisoned the state's groundwater with cancer-causing heavy metals. Duke's own scientific assessments of its ash dumps will be relied upon by state regulators charged with deciding how much clean-up is called for, and how quickly. In this exclusive insightus investigation we take a close look at Duke's science, exposing deficiencies which stack the deck in the company's favor and put North Carolinians' lives at risk.

Rowan County North Carolina residents Bryant and Sherry Gobble look out from their back yard across a Duke Energy coal ash dump, marked by dead trees and black water, at the company’s Buck Steam Station generating facility. (Chuck Burton, AP)

Part I: Coal Ash - North Carolina's Invisible Disaster

In the American electric utility industry, King Coal is still king. Despite steadily growing adoption of alternative fuels, today coal still powers more than a third of all electrical generation in the U.S., edging out the two next most popular fuels - natural gas (32%) and nuclear power (20%).

And among coal-burning electric utilities, none is more significant than North Carolina-based Duke Energy - America’s largest as measured by market value ($55 billion) or generating capacity (58 gigawatts). Like the industry as a whole, more than a third of Duke’s generation is powered by coal.

Today Duke’s coal-fired power plants no longer belch dense black smoke as they once did. EPA-mandated emission controls remove over 99% of fly ash - the fine grit that makes coal smoke black - before it can be released into the air. But all of that coal ash which no longer rises into the sky still needs to go somewhere. And there’s a lot of it for utilities like Duke to deal with: according to the U.S. Energy Information Administration, utilities burn nearly 1 billion tons of coal annually, producing and collecting nearly 200 billion pounds of coal ash. It’s a witch’s brew of toxic heavy metals including hexavalent chromium, the cancer-causing chemical made famous by the poisoning of Hinkley, California by Pacific Gas and Electric, as chronicled in the Julia Roberts film, Erin Brockovich.

Thanks in part to relentless industry lobbying, EPA does not regulate coal ash as a toxic waste, leaving utilities like Duke free to dispose of it carelessly: by mixing it with water and piping the toxic sludge into unlined ponds on power plant properties. No one knows exactly how much coal ash has thus accumulated beside America’s rivers at facilities like Duke Energy’s Buck Station (photo above), but an estimate based on historical records suggests that about 8 trillion pounds of it have accumulated in utility company impoundments since the 1960s.

Out of sight of most Americans - as well as of their elected representatives - the specter of abandoned coal ash mostly remains out of mind as well. The occasional startling disaster can still call it back to momentary attention, as did 2008’s Kingston, Tennessee spill of over 1 billion gallons from a Tennessee Valley Authority ash dump into the Emory River (requiring six years and $1.2 billion to clean up), or the strikingly similar 2014 spill of 39,000 tons from Duke Energy’s Dan River power plant.

But even in the absence of such accidents, coal ash remains a silent, invisible environmental disaster in progress. Rainwater percolating down through America’s unlined coal ash impoundments dissolves the ash’s toxic chemicals and carries them into the soil, down to the water table, and from there in whichever directions the groundwater flows. If private or public water wells happen to be in the path of those underground rivers, those wells finally deliver the toxic chemicals to all who drink, cook, or bathe with that water (Figure 1). In North Carolina alone (which claims the fourth largest number of private water wells in the country) that puts roughly 3 million residents...nearly a third of the state’s risk of mercury, lead, arsenic, vanadium and chromium poisoning.

Figure 1: The coal ash contamination cycle. (1) Coal-burning power plant recovers fly ash from smokestacks, mixes it with process water from nearby river, and pumps the resulting sludge into shallow, unlined impoundments on bare ground. (2) Process water and rainwater percolate down through the ash deposit, dissolving toxic chemicals and carrying them into the soil beneath the impoundment (V: vanadium; Hg: mercury; As: arsenic; Cr: chromium; Pb: lead). (3) When the sinking column of contaminated water reaches the water table, its toxic chemicals are next transported in the direction of groundwater flow (here, from right to left). (4) Drinking water supply wells ‘downstream’ of this contaminated flow deliver the toxic chemicals to homes, where residents are exposed while cooking, drinking, or bathing with the tainted water.

Ironically, this figure actually illustrates a 'best-case' scenario – where a coal ash dump is situated well above the water table. In the alternative 'worst-case' scenario (common across North Carolina), deeply excavated impoundments extend below the water table, placing their coal ash in direct, continuous contact with groundwater and thus facilitating very rapid transport of toxic chemicals from the ash to distant water supply wells.

North Carolina’s Coal Ash Management Act of 2014: Duke Energy’s Get-Out-of-Jail-Free Card?

By patiently cultivating friends in high places, Duke Energy has long avoided being held accountable for careless management of its coal ash waste.

In 1995 a young Duke Energy executive, Pat McCrory, sought and gained his employer’s permission to run for mayor of Charlotte, the utility’s corporate home, while remaining on Duke's payroll. Duke obliged, and obliged yet again when McCrory won that office, adjusting his work schedule to enable the new mayor to continue his service to Duke even while presiding in city hall.

According to city councilman John Autry, "we always considered [McCrory's] Duke employment as a 'sugar daddy job'" .

After a record-setting 14 years as Charlotte's mayor, McCrory finally resigned from Duke in 2008 in preparation for what would prove to be an unsuccessful bid for North Carolina's governorship. But running again in 2012, McCrory won, thanks in no small measure to $1 million in direct and indirect campaign contributions from Duke.

Its decades of generosity to McCrory began to pay dividends for Duke as North Carolina’s new Republican governor appointed fellow former Duke executives to administrative positions across state government, including NC’s Department of Environment and Natural Resources (the state’s pollution watchdog). But Duke's real payday came a year later, just after its Dan River coal ash spill, when McCrory and fellow Republicans in the state legislature, attempting to get out ahead of the environmental disaster’s political blowback, rushed into law The Coal Ash Management Act of 2014 (CAMA).

CAMA's first-in-the-nation requirement to close every one of Duke's wet coal ash dumps across the state — fourteen in all — may seem environmentally friendly, but the law's timeline is accommodating to Duke in the extreme, permitting the dumps to remain open for from five to fifteen more years (depending on their risk levels). The law blazes an exceedingly complex pathway toward site closure and remediation, requiring numerous decisions to be made along the way by the same Department of Environmental Quality which Gov. McCrory has stacked with former Duke Energy executives and other ‘business-friendly’ political appointees. As a consequence, critics worry that CAMA’s regulatory path may be ripe for gaming by Duke and its old friend, the governor.

     Part I: Coal Ash - North Carolina's Invisible Disaster
     Part II: How Trustworthy Are Duke's Self-Assessments? An insightus investigation
     Part III: Bad Science, Shady Politics: Duke's and McCrory's 'Belt and Suspenders' Strategy?


North Carolina's public comment period for coal ash remediation plans ends April 18, 2016. Alarmed by Duke's bad science outlined here? Let state officials know at

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