Appalachian Power completed a six-year, $2 billion effort to install scrubbers and other environmental controls at its coal-fired electric generating plants.

The effort is part of a $4.2 billion investment in environmental retrofits. The upgrades began in 2004 by parent company American Electric Power to address plant emissions of sulfur dioxide and nitrogen oxides.

Installing environmental controls helps Appalachian’s plants meet federal Environmental Protection Agency clean air regulations. Scrubbers added to the company´s Mountaineer and John Amos plants reduce those plants´ SO2 emissions by 98 percent. Selective catalytic reduction equipment reduces NOX emissions by as much as 90 percent.

Construction costs for the Amos Plant scrubbers totaled more than three times the original cost to build the entire plant in the mid-1970’s. In addition to construction costs, it requires more than 200 additional employees to maintain and operate the Mountaineer and Amos scrubbers.

The company anticipates it will need to install additional controls at its coal-burning electric generating plants in future years, depending on the requirements of environmental regulations currently under development. The company´s plants use 13 million tons of coal each year.

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