McARTHUR, Ohio — Austin Powder’s Red Diamond explosives manufacturing plant in Vinton County resumed limited operations on Monday, following a nitrogen oxide gas release on June 11 that prompted evacuations and temporary flight restrictions. The incident, caused by a temperature increase in a 5,000-gallon nitric acid tank containing about 3,000 gallons, produced a yellow-brown plume of nitrogen oxide gas over the facility at 32000 Powder Plant Road, northwest of McArthur and southwest of Zaleski.
The gas release led to the evacuation of surrounding areas, including the village of Zaleski, with approximately 780 residents, and triggered a 30-nautical-mile flight restriction radius around the plant. Testing on Monday of air, water, and the site confirmed no remaining health hazards, allowing the phased restart of operations. Employees, part of the county’s largest employer, have returned to work.
The company, headquartered in Cleveland, reported that the nitric acid remained fully contained, with a modest amount of gas vented through the plant’s safety system, preventing more severe consequences. Austin Powder is conducting an internal investigation to identify the cause of the temperature rise, implementing engineering and procedural changes to prevent future incidents, and reviewing nitric acid storage systems at all its sites. Affected employees received paid time off during the closure.
Austin Powder is offering reimbursement for residents and employees who incurred expenses, such as hotel stays or gas, due to the evacuation. Residents can contact the company at 216-839-5469 or submit claims at [email protected].