Wind drives chemical leak from Ohio explosives plant into nearby communities

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VINTON COUNTY, Ohio – Communities were under evacuation Wednesday after a large chemical leak from an explosives plant in southeast Ohio sent hazardous air into nearby areas.

Jackson County Emergency Manager Robert Czechlewski said the leak at Austin Powder Company’s Red Diamond facility happened about 8:30 a.m. Wednesday. 

Ohio Department of Environmental Protection officials said no injuries were reported from the leak. 

"A tank reaction released nitrogen oxide gas into the air, but the release has since stopped," the Ohio EPA said. 

Officials said the chemical wafting into the air was nitric oxide. Potential exposure can include irritated eyes, drowsiness and possible loss of consciousness. The leak on the ground at Red Diamond was nitric acid, but a reaction created a nitric oxide plume that was seen over the region.

After the leak, winds expanded the concerns to areas outside the immediate area of the plant.

A large brown plume of nitric oxide seen over Vinton County, Ohio after a chemical leak from the Austin Powder Red Diamond facility on June 11, 2025. 

(Edith Conner / FOX Weather)

Around noon, the Vinton County Sheriff's Office evacuated residents in the village of Zaleski, as well as areas along Creek Road, Morgan Road, Infirmary Road and State Route 677.

The evacuation orders were lifted about 4:30 p.m. 

Wind conditions as of early Wednesday afternoon near the site of the chemical leak. 

(FOX Weather)

The National Weather Service in Charleston, West Virginia, provided plume updates to emergency managers showing the plume was heading south from the facility. 

Czechlewski said wind conditions would determine how soon evacuated residents could return home.