State fines South Mississippi plant for releasing too much of an air pollutant

The Pearl River Plant operated by the Calgon Carbon Corp. at Port Bienville in Hancock County has been fined $56,000 for exceeding air emission limits for nitrogen oxides.

Calgon agreed to the fine under a recent order entered with the Mississippi Department of Environmental Quality.

Low nitrogen oxide levels in the air can irritate the eyes, nose, throat, and lungs, with possible symptoms including a cough, shortness of breath and nausea. Exposure over one to two days can cause fluid to build up in the lungs, while exposure to higher levels can cause more serious symptoms and even death.

The federal Clean Air Act sets standards for six pollutants, including nitrogen oxides, to ensure ambient air is within required limits. MDEQ enforces air pollution limits in Mississippi. Nitrogen oxides include the gases nitric oxide and nitrogen dioxide, which reacts in the atmosphere to form acid rain, according to the Environmental Protection Agency.

MDEQ found that Calgon exceeded a nitrogen oxides limit of 4.19 pounds per hour, averaged over three hours, when 5.10 pounds per hour was released during testing on Aug. 14, 2024.

A test at a different emission point, on Aug. 13, 2024, showed a nitrogen oxides level of 4.40 pounds per hour. December tests at both locations showed Calgon’s Pearl River Plant was in compliance with limits on nitrogen oxides.

“Calgon Carbon’s team implemented corrective actions at our Pearl River facility and has remained in compliance since December of last year,” Calgon senior vice president Jenalle Brewer said in an email.

The Hancock County plant produces activated carbon products used in purification and manufacturing processes, according to its website.

This story was originally published June 11, 2025 at 12:01 PM.

Anita Lee

Sun Herald

601-909-0638

Anita, a Mississippi native, graduated with a journalism degree from the University of Southern Mississippi and previously worked at the Jackson Daily News and Virginian-Pilot, joining the Sun Herald in 1987. She specializes in in-depth coverage of government, public corruption, transparency and courts. She has won state, regional and national journalism awards, most notably contributing to Hurricane Katrina coverage awarded the 2006 Pulitzer Prize in Public Service. Support my work with a digital subscription