More than a dozen ponds containing coal ash — the toxic byproduct of burning coal — are located in flood zones throughout the United States, putting them at risk of flooding during storms or high water, according to a report released this week by a coalition of environmental and public interest groups.
The report comes as the Trump administration seeks to weaken standards for coal ash disposal at the request of industry, rolling back the first-ever federal regulations on disposal for coal ash.
“Putting billions of gallons of toxic coal ash next to our rivers and drinking water — that’s just an accident waiting to happen,” John Rumpler, senior director of Environment America’s clean water program and co-author of the report, said in a press statement. “We should be phasing out these toxic pits. The last thing we should be doing is weakening the few standards we already have in place to limit their pollution of our waters.”
Coal ash is the second-largest form of waste in the United States, with more than 100 million tons produced each year. To store coal ash, coal-fired power plants — which tend to be located near water sources used for cooling the power plant’s equipment — combine the ash with water and store it in pits, known as coal ash ponds.
Historically, these pits have been unlined, leading environmental groups to raise concerns about whether toxic compounds found in coal ash — like lead, arsenic, and mercury — could be leaching into nearby groundwater. Those fears have largely been backed up by industry data, which has shown elevated levels of toxic pollutants like arsenic and radium in the groundwater near more than 70 coal ash disposal sites across the country.
But the report from Environment America raises concerns beyond groundwater contamination. It warns that fourteen coal plants with onsite coal ash storage ponds are located within Federal Emergency Management Agency (FEMA) 100-year flood zones, meaning that the area is reasonably expected to flood at least once a century. These plants generate 8.4 million tons of coal ash each year, and at least six of those ponds have been designated by the Environmental Protection Agency (EPA) to be in poor condition.
“While hundreds of coal plant sites across the country likely put water at risk, those with coal ash ponds located in flood zones may pose an elevated threat, as being in a flood zone indicates both proximity to water and risk of flooding,” the report reads, adding that fourteen plants located in flood zones is likely a conservative estimate.
A large number of these coal plants sit along the Ohio River, which provides drinking water to more than 3 million people.
Evidence suggests that as climate change continues, a warmer atmosphere will be able to hold more moisture, resulting in more frequent extreme precipitation events. As heavy downpours increase, it’s possible that coal ash ponds that otherwise would have only been at risk of flooding every 100 years will be at more frequent risk of flooding.
If a coal ash pond were to be hit by flooding, it’s possible that the toxic waste could then flow into nearby streams or rivers, contaminating surface water near the spill.
In 2016, Hurricane Matthew dumped 18 inches of rain in parts of North Carolina, causing rivers across the state to rise to dangerously high levels. Environmental groups were concerned that the flooding could breach some coal ash ponds operated by Duke Energy. The utility initially said that it did not expect the flooding to breach the ponds, but later admitted that “an unknown amount of coal ash” had in fact been discharged during the flooding at one of its coal-fired power plants.
The report released this week calls for a moratorium on new or expanded coal ash ponds, and calls for old coal ash ponds to be excavated and lined in order to keep the waste from seeping into groundwater.
Under the Trump administration’s proposal to rollback Obama-era rules on coal ash, however, utilities would be able to decide if and when they tested for groundwater contamination, rather than requiring all utilities to adhere to a mandated schedule as the Obama-era regulations would have required. The rollback would also give a large amount of autonomy to states in crafting their own requirements for coal ash disposal and cleanup.
“The existing EPA policies on coal ash don’t even classify it as ‘hazardous waste.’ Now, the EPA is trying to weaken coal ash policies even more,” Rumpler said. “That’s just inviting disaster for our rivers.”