State holds Cliffside plant to tough pollution controls

State regulators on Monday got tougher on Duke Energy.

Four months after approving a controversial coal-burning power plant in the Blue Ridge foothills, the N.C. Department of Environment and Natural Resources said that Duke's Cliffside plant must meet the most stringent pollution controls available.

The decision, hailed as a victory by environmental groups, likely would make Cliffside the cleanest coal-burning power plant in the nation.

The agency said that maximum pollution controls are required by the federal Clean Air Act. The federal law had been in dispute and was not applied in January when the state issued an air-quality permit for Duke to build Cliffside.

Environmental groups that have been trying to kill the Cliffside project for more than a year say the new pollution controls could be 10 times stricter than the requirements approved in January.

Now the state's biggest energy company faces the prospect of having to modify the $2.4 billion power plant's design, which could raise the price.

Monday's ruling requires maximum controls for more than 50 hazardous pollutants. But of greatest concern is mercury, which settles in waterways, contaminates fish and ultimately causes birth defects in humans.

More than 50 coal-fired power plants have been canceled or delayed in the past year, but Duke has steadfastly promoted Cliffside as a technological marvel that will improve air quality. The plant's design won Duke a $125 million award from the U.S. Department of Energy to promote the development of clean coal technology.

Duke began construction on the 800-megawatt power plant about an hour west of Charlotte in January. It had been scheduled to begin generating electricity in 2012.

Lawsuits

Monday's ruling reopens the Cliffside case, giving new hope to environmental groups. Their strategy had been to press legal challenges and force Duke to abandon Cliffside in the face of mounting costs and public opposition.

Duke Energy officials are now reviewing how to respond to regulators. The company has until June 13. Refusal to comply would almost certainly set off another round of lawsuits.

Environmental organizations have already sued the state for issuing the air permit and plan to ask a federal court to force Duke to stop construction.

Bill Ross, the secretary of environment and natural resources, said Monday that the state is requesting that Duke conduct an additional technical analysis for maximum pollution controls, a process that could take three to six months.

It's possible that Duke's pollution analysis will show that Cliffside requires little or no design modifications, Ross said. But environmentalists doubt the plant would fare well under a rigorous pollution control standard.

Duke designed Cliffside to comply with the best available technology, which is considered less stringent than maximum pollution controls.

Maximum controls require detailed technical analyses that show the plant is at least on par with the cleanest coal-burning plant in operation, said John Suttles, a lawyer for the Southern Environmental Law Center in Chapel Hill.

"They didn't go out and look at the best-controlled existing power plant and say, 'We are going to meet or beat that,' " Suttles said.

As designed, Cliffside would remove more than 99 percent of sulfur dioxide, more than 90 percent of nitrogen oxides and more than 90 percent of mercury emissions.

The Southern Environmental Law Center cites more than a dozen coal burning plants in the nation that trap more pollutants than Cliffside would.

Superior technology includes so-called ultra supercritical pulverized coal plants that emit less pollution because they burn coal more efficiently, requiring less fuel to generate the same amount of electricity.

Even cleaner are coal gasification plants. These facilities convert coal into a clean-burning gas. Duke Energy is building such a plant in Indiana.