More challenges to Cliffside expansion

The Southern Environmental Law Center appealed a state air-quality permit on behalf of the Environmental Defense Fund, Southern Alliance for Clean Energy, National Parks Conservation Association and the Sierra Club. Duke formally broke ground on the $1.8 billion project to add an 800-megawatt boiler to Cliffside, which is 50 miles west of Charlotte.

Actual construction began after the state permit was issued in January.

The company announced at the groundbreaking that the federal government had doubled the size of "clean coal" tax credits awarded to the plant to $125 million. Environmentalists say the fight over Cliffside has gained national prominence, in part because of Duke's calls for action on greenhouse gases.

Coal-fired power plants are major contributors to greenhouse gases. The new boiler is expected to release 5.5 million pounds of carbon dioxide per year. Duke says the plant will feature state-of-the-art pollution controls that will sharply reduce emissions of pollutants that form ozone, haze and contaminate rivers.

The challenge focused on:

- Carbon dioxide, on which the environmental groups say the N.C. Division of Air Quality should have placed emission limits. Duke says no limits are required, since carbon dioxide isn't regulated. The groups said Duke's plan to offset Cliffside carbon dioxide emissions by retiring older plants is "riddled with loopholes that could allow the company to never reduce CO2 emissions." Duke denied that claim, saying the air permit requires those reductions.

- Mercury, a toxic element that contaminates Eastern North Carolina rivers. The environmental groups say Cliffside's permit doesn't require the most stringent mercury-removal technology available. A recent federal court ruling, they say, demands that the issue be revisited. State officials say they don't have to reopen the permit to re-evaluate mercury controls. Duke says its pollution-control contractor has guaranteed 90 percent mercury capture.

- Sulfur dioxides and nitrogen oxides, which form haze, acid rain and ozone. The state did not require analyses of the impacts of those emissions from the plant.

Duke says emissions from the Cliffside will decline by 80 percent for sulfur dioxide, 50 percent for nitrogen oxides and 50 percent for mercury. Two other groups, the N.C. Waste Awareness and Reduction Network, or NC WARN, and Appalachian Voices filed papers March 19. They asked an administrative law judge to put the permit on hold and stop construction.

No ruling has been made.