Even with 157 million tons of ash in ponds and landfills across North Carolina, the concrete industry says it can't secure enough to meet demand. As cleanup efforts in the state ramp up and Duke Energy complies with state and federal deadlines to close its ash ponds, concrete producers question why Duke isn't doing more to recycle and reuse the fly ash.

"They're proceeding with the cleanup but they're really not pursuing a strategy to put it in the hands of somebody else, other than put it in the ground," said Henry Batten, president of Charlotte's Concrete Supply Co.

The design of Duke's power plant boilers, and the use of "scrubbers" to reduce air pollutants, results in ash with too much carbon to be usable in concrete. The ash can be reprocessed, but Duke says the idea is not economical. Duke cites costs associated with reprocessing and hauling, and also that long-term commitments to sell reprocessed ash have been hard to find.

But the concrete industry insists that nearly 46.5 million tons of fly ash is expected to be needed to make concrete in the Carolinas and Virginia over the next 15 years, and urge that changes are made to legislation so ash could be reused instead of simply buried.

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