Tennessee Valley Power Plants to Cut Sulfur Dioxide

KNOXVILLE, Tennessee, October 9, 2001 (ENS) - The Tennessee Valley Authority plans to install scrubbers on five coal burning power plants that will slash sulfur dioxide emissions by more than 200,000 tons per year. The new emissions control equipment will help clear the air over Great Smoky Mountains National Park, named as one of the United States' 10 most endangered parks for the past three years.

The Tennessee Valley Authority (TVA), the nation's only federally owned electric utility, says it will reduce sulfur-dioxide emissions by adding flue-gas desulfurization systems - or scrubbers - to five coal fired power plants as part of its efforts to improve air quality in the Tennessee Valley and comply with the Clean Air Act.

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Aging coal burning power plants are among the major industrial producers of haze (Photo by Carole Swinehart, courtesy Michigan Sea Extension)
Single scrubbers will be installed at Bull Run, Paradise, and Colbert Fossil Plants, and two will be added to Kingston Fossil Plant. They will cost about $1.5 billion altogether and when completed will collectively reduce emissions of sulfur dioxide by more than 200,000 tons per year, TVA says.

At that point TVA will have reduced total emissions by 85 percent since 1977, the company says. The new sulfur controls will help decrease haze, acid rain and particulate matter pollution.

"The story of TVA's air pollution legacy in the Tennessee Valley has a new chapter, and this one's a pleasure to read," said Don Barger, southeast regional director of the National Parks Conservation Association (NPCA). "Coal fired power plants produce more than 75 percent of the sulfur responsible for the haze and acid deposition that threaten the health of Great Smoky Mountains National Park and its visitors."

For three years, NPCA has named Great Smoky Mountains National Park as one of America's 10 most endangered parks. NPCA, the only U.S. nonprofit group dedicated solely to protecting, preserving, and enhancing the national park system, issues a list each year of parks threatened by pollution, development, and other problems.

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Haze through the trees at Great Smoky Mountains National Park (Photo courtesy National Park Service)
"Visibility impairing haze has reduced views in the park by 80 percent in summer months when compared to natural conditions," continued Barger. "Sulfur pollution contributes to the heightening of asthma and chronic lung disease and even shortens lives."

TVA says design work on the new sulfur scrubbers will start in 2003. Peak construction activities will have to be delayed until installation is completed on another set of emissions control equipment - the TVA is now in the midst of a $1 billion program to reduce nitrogen oxide emissions at its plants by constructing 18 selective catalytic reduction systems on 25 coal fired generating units.

That project is one of the most massive pollution control programs in the nation. The lack of availability of craft workers and other resources needed to install the emissions control equipment will affect the completion date of the new sulfur scrubber project, TVA said.

Six sulfur scrubbers are already in place on TVA's largest units - two at Cumberland Fossil Plant, two at Paradise, and two at Widows Creek. The decision on where to install the new scrubbers was based on estimates of the greatest environmental benefit for the investment and the greatest improvement in air quality in the mountains of east Tennessee and western North Carolina.

When the project is completed, TVA will have spent about $5 billion to reduce emissions from its coal fired plants.

"TVA's proposed reductions will go a long way on what we know is still a very long journey toward cleaner, healthier air, lifting the huge burden of pollution on the parks and on human health," said NPCA's Barger.

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Fall colors in Great Smoky Mountains National Park (Photo courtesy NPCA)

The NPCA currently has lawsuits against three of the four TVA plants targeted for new sulfur controls. Many older, coal fired power plants have been operating for decades without meeting the same standards as new facilities, despite making modifications that make them accountable for current standards under the Clean Air Act.

In November, 1999, the U.S. Environmental Protection Agency (EPA) issued an administrative order against the TVA, charging that the utility violated the Clean Air Act by making major modifications to many of its coal burning plants without installing the equipment required to control smog, acid rain and soot.

In May 2000, the TVA sued the EPA, saying new emissions controls ordered by the agency are unnecessary and could require a 14 percent electricity rate increase. TVA joined several private power companies in challenging EPA's administrative order requiring older coal fired plants to be updated with modern pollution reduction equipment.

Collectively, electric utility plants in the U.S. account for nearly 70 percent of sulfur dioxide (SO2) emissions each year, and 30 percent of nitrogen oxide (Nox) emissions. Sulfur dioxide interacts in the atmosphere to form sulfate aerosols, which can harm people who suffer from asthma or bronchitis. Nitrogen oxides are major producers of ground level ozone or smog, which can decrease lung function, particularly in children.

Particulate matter, or soot, can damage lung tissue and contribute to cancer and respiratory disease.

Both SO2 and NOx interact with water and oxygen to form acid rain, which degrades forests, damages waterways, threatens aquatic species and accelerates the decay of buildings.