Charleston, W.Va. -- State regulators on Friday blamed another "blue haze" incident in the Kanawha Valley on American Electric Power Co.'s John Amos Power Plant near St. Albans.

"It appears to be Amos," said John Benedict, director of the West Virginia Department of Environmental Protection's Division of Air Quality.

At about 2 p.m. Friday, Metro 911 dispatchers reported receiving complaints about a blue haze in the western end of Kanawha County. The DEP quickly sent inspectors to the area, and later did an aerial inspection in the agency's helicopter.

Benedict said inspectors traced the blue-white plume to the Amos plant, located across the Kanawha River from Poca.

By late afternoon, a white fog hugging the river was moving through the valley into downtown Charleston. Benedict said his inspectors noted that a bluish-white cloud was at its thickest near the Interstate 64 bridge in South Charleston.

Continuous air monitors the DEP operates in downtown Charleston were not showing significant problems, Benedict said. Monitors in outlying areas run on 24-hour cycles and would not provide any data until after midnight, Benedict said.

Benedict said his staff believes the incident was similar to one on Jan. 25, but that it was perhaps less severe. Emissions from Amos appeared to be dispersing more vertically, leaving less of a plume hanging over the valley.

"It's not as distinct as before," Benedict said.

Shortly after lunch on Jan. 25, a blue haze started to appear in the air across the Kanawha Valley. Residents called emergency officials to complain about a strange odor, and asked if there was a chemical leak. County officials surveyed area plants, but none reported any unusual releases or operating problems.

Charleston, W.Va. -- State regulators on Friday blamed another "blue haze" incident in the Kanawha Valley on American Electric Power Co.'s John Amos Power Plant near St. Albans.

"It appears to be Amos," said John Benedict, director of the West Virginia Department of Environmental Protection's Division of Air Quality.

At about 2 p.m. Friday, Metro 911 dispatchers reported receiving complaints about a blue haze in the western end of Kanawha County. The DEP quickly sent inspectors to the area, and later did an aerial inspection in the agency's helicopter.

Benedict said inspectors traced the blue-white plume to the Amos plant, located across the Kanawha River from Poca.

By late afternoon, a white fog hugging the river was moving through the valley into downtown Charleston. Benedict said his inspectors noted that a bluish-white cloud was at its thickest near the Interstate 64 bridge in South Charleston.

Continuous air monitors the DEP operates in downtown Charleston were not showing significant problems, Benedict said. Monitors in outlying areas run on 24-hour cycles and would not provide any data until after midnight, Benedict said.

Benedict said his staff believes the incident was similar to one on Jan. 25, but that it was perhaps less severe. Emissions from Amos appeared to be dispersing more vertically, leaving less of a plume hanging over the valley.

"It's not as distinct as before," Benedict said.

Shortly after lunch on Jan. 25, a blue haze started to appear in the air across the Kanawha Valley. Residents called emergency officials to complain about a strange odor, and asked if there was a chemical leak. County officials surveyed area plants, but none reported any unusual releases or operating problems.

Federal and state officials later concluded the incident likely was caused by emissions from the huge Amos power station.

In a detailed report issued in May, DEP officials concluded that weather conditions transformed sulfuric-acid emissions from the plant into an aerosol, creating the blue mist.

Burning coal with sulfur in it produces sulfur dioxide. Inside plant stacks, some of that sulfur dioxide is converted to sulfur trioxide. When the sulfur trioxide exits the stack, it reacts with moisture in the air to form sulfuric acid.

Over the past few years, AEP has added pollution control equipment aimed at reducing nitrogen oxide emissions, but that equipment also can enhance the creation of sulfur trioxide, increasing the potential for sulfuric-acid emissions.

After the January incident, AEP notified the U.S. Environmental Protection Agency that Amos was releasing up to 32,500 pounds of sulfuric acid per day, nearly eight times the company's previous estimate.

The DEP cited AEP for the January incident, but the company is appealing.

On Friday, AEP spokesman Phil Moye said Amos plant officials reported no problems at the facility.

"The plant is operating within its normal operational parameters," Moye said, "essentially the same as it did yesterday and the day before."

Reach Ken Ward Jr. at kw...@wvgazette.com or 348-1702.