March 23, 2014

Environmentalists: Charlotte airport coal ash storage is likely better than unlined ponds

When the Charlotte City Council hears the details Monday of a proposal to bury toxic coal ash at Charlotte Douglas International Airport, supporters of the plan will point to a similar project at Asheville’s airport that’s been underway for more than seven years.

When the Charlotte City Council hears the details Monday of a proposal to bury toxic coal ash at Charlotte Douglas International Airport, supporters of the plan will point to a similar project at Asheville’s airport that’s been underway for more than seven years.

There, environmentalists say, wrapping, sealing and burying ash that was formerly stored in unlined ponds has proved to be a better solution – so far. But they say the long-range risks are unknown and that any coal ash burial program must be carefully managed to prevent leaching and contamination.

“The reality is, it’s much better than the way they store it at the power plant,” said Hartwell Carson, the French Broad riverkeeper. He and other environmental groups have been monitoring the project to take millions of tons of coal ash from a Duke Energy power plant and use it as a “structural fill” material to grade land in preparation for construction.

“I don’t have a lot of concerns about it in the short term,” Carson said. “Fifty, 100 years from now? I’d say all bets are off.”

Julie Mayfield, co-director of the Western North Carolina Alliance, said there are definite advantages to storing the coal ash wrapped up in a lined landfill. “Basically, it’s like a big burrito,” she said. “It’s a decent solution.”

So far, details are scant on the Charlotte Douglas proposal; the City Council will not vote Monday. Officials say they are examining a plan to take millions of tons of coal ash from the retired Riverbend Steam Station on Mountain Island Lake – Charlotte’s drinking water source – and burying it in lined, capped enclosures at the airport. There, it would be used to grade land for future construction projects, possibly saving the airport millions.

Duke plans to work with Kentucky-based Charah Inc., a contractor, to dig up the ash from Riverbend and re-bury it at the airport. Charah is also the contractor for the Asheville project.

But officials haven’t said where the ash would be buried and how the Catawba rivershed and Lake Wylie would be protected. Much of the airport’s land drains there. Coal ash, which is left over from burning coal to create electricity, contains toxic heavy metals, such as mercury and arsenic.

Asheville shares its progress

When Asheville Regional Airport started the first phase of the fill project, environmentalists worried. Carson, the riverkeeper for the French Broad, said Duke and Charah used a flimsy liner and his group documented coal ash flowing downstream to a nearby neighborhood that uses well water.

“They located this huge amount of coal ash with a weak liner on a steep slope that drained to a community on drinking wells,” Carson said. “It’s extremely difficult to keep that stuff from running off.”

Are there any lasting effects?

“It’s hard to tell at this point,” Carson said. “It’s probably too early to conclude if it’s leaching.”

Asheville Regional Airport declined to make any officials available to interview but did answer written questions. Airport spokeswoman Tina Kinsey said there weren’t any problems with runoff, and that while water flowing from neighboring properties runs through the airport, it doesn’t go through the coal ash site.

“There has been some public misperception about where this runoff originates, which most likely explains the incorrect information about this that was relayed to you,” she wrote.

In a written statement with several identical sentences to the airport’s statement, Charah also denied there were any problems with the first phase of the coal ash fill project.

“Charah believes it has provided the best possible assurances that the engineered fills constructed at the Asheville airport and proposed for the Charlotte airport are safe and will protect the environment and public health,” said Scott Sewell, Charah’s chief operating officer, in a statement provided by Charlotte-based law firm Moore & Van Allen.

Process is ... the ‘gold standard’

Carson said the company has taken more stringent safeguards since then.

“To their credit, they did the second phase much better,” Carson said.

While the first phased used a liner and clay cap to encase the ash, the second uses an all synthetic liner made of heavy-duty plastic, sealed all the way around. There is a system in place to collect leachate, which is then taken to a wastewater plant and treated. Charah said the liners should last hundreds of years.

“This process is considered the ‘gold standard’ for coal ash management,” Kinsey wrote.

Charah and Duke have installed groundwater monitoring wells on the site. They’re tested quarterly, and so far Kinsey said the testing shows “water quality standards are being met.”

So far, Duke and Charah have moved 3 million tons of coal ash from the power plant to the airport. Asheville Regional has saved $12 million on the cost of fill dirt it might have otherwise bought, Asheville officials said, though no projects have been built yet on the graded land.

Documents from the city of Charlotte suggest Charlotte Douglas could save up to $30 million if it uses an estimated 4 million pounds of Duke’s ash to fill in land for future construction projects. The biggest construction project proposed at the airport is a fourth parallel runway that could be up to 12,000 feet long. Charlotte Douglas spent $70 million to move 9 million tons of earth for its last runway project, the third parallel runway that opened in 2010.

Coal ash isn’t regulated as a hazardous material, although the Environmental Protection Agency is expected to issue tougher standards later this year.

Charah said several other airports have used coal ash as a building material. Houston’s George Bush Intercontinental Airport, the only one of a similar size to Charlotte Douglas, used the material as part of the concrete to pave a runway.

Environmentalists say coal ash won’t disappear, leaving the question of what to do with the millions of tons of it sitting in unlined ponds throughout the state. For now at least, a sealed, buried landfill at the airport might be the best option.

“I certainly don’t think it’s a bad option,” Carson said. “It’s pretty safe – as long as it’s monitored and doesn’t leak.”

Related content



Editor's Choice Videos