Pollution reduces visibility in North Carolina's mountains by 80 percent during the summer, an expert testified Thursday in the state's lawsuit against the Tennessee Valley Authority.
Lyle Chinkin told a federal judge that without pollution, visitors to Great Smoky Mountains National Park could see ridges 77 miles away, the Asheville Citizen-Times reported.
Chinkin said pollution has cut visibility to 15 miles. Chinkin is president of a California-based air quality research firm.
The lawsuit aims to force the TVA to cut pollution emitted by its coal-fired power plants. The state has argued that emissions of sulfur dioxide, nitrogen oxides and mercury drift from nearby states into North Carolina, hurting air quality and the economy.
Chinkin said the information came from a National Park Service report. His testimony came on the fourth day of the trial before U.S. District Court Judge Lacy Thornburg, who is hearing the case without a jury.
The lawsuit asks that TVA be required to abide by pollution limits imposed on North Carolina utilities.
Earlier testimony showed TVA could emit no more than 140,000 tons of sulfur dioxide and 60,000 tons of nitrogen oxides annually if it met state law.
TVA has said it emits 374,000 tons of sulfur dioxide a year — less than the 875,000 tons it put out a decade ago.