Area police, firefighters and paramedics from Ogle County responded about 4:41 p.m. Tuesday, March 10, 2026 to a report of a person with chemical exposure at the Exelon/Constellation Byron Generating Station (a two-unit nuclear power plant), 4450 North German Church Road in Byron, Illinois. Byron Fire Protection District firefighters and paramedics were first on the scene and quickly reported there six patients “with chemical exposure.” The first available patient count was six at about 5:14 p.m.
UPDATE:
Non-radiological chemical (identity not disclosed) used in nuclear plant system leaked from a holding tank in the turbine building.
No serious injuries or illnesses reported.
Eight EMS transports to hospitals (hospitalized as precaution).
Ten self-transports to hospitals.
An alert went out on IFERN (Interagency Fire Emergency Radio Network) at 5:32 p.m. calling for mutual aid assistance of a mass casualty incident involving “chemical exposure
A MABAS Division 18 Box Alarm (Ambulances Only) on Box #12 at “Byron Nuke Plant” activated by 5:32 PM.
An EMS Box Alarm (Ambulances) 2ND ALARM was activated at 5:34 PM.
A MABAS Division 18 Box Alarm #18-2 HazMat activated at 5:50 PM.
An EMS Box Alarm (Ambulances) 3RD ALARM at 5:54 PM.
Each box level alarm amounts to a response of about four to six mutual aid ambulances from a countywide area.
The Byron Clean Energy Center is a two-unit nuclear power plant located in Ogle County, Illinois, 2 miles (3.2 km) east of the Rock River, and south of Illinois Route 72.
The reactor buildings consist of two Westinghouse Four-Loop pressurized water reactors. Operation of Unit 1 and Unit 2 began in September 1985 and August 1987 respectively.
The nuclear power plant is owned and operated by Constellation Energy, which spun off from Exelon in 2022.
Initially, there has been no known wide area leak or plume alert.
When a plume or major leak exists: The Nuclear Regulatory Commission defines two emergency planning zones around nuclear power plants: a plume exposure pathway zone with a radius of 10 miles, concerned primarily with inhalation exposure and airborne radioactive settling contamination. An ingestion pathway zone consists of about 50 miles, concerned primarily with ingestion of food and liquid contaminated by radioactivity.
Downtown Arlington Heights is about 67 miles east of the Byron Nuclear Generating Station, 4450 North German Church Road in Byron.
Downtown Chicago is about 86 miles east southeast of the Byron Nuclear Generating Station, 4450 North German Church Road in Byron.
DEVELOPING …
The information in this article is an early report published before any summary information was confirmed or released by police or fire authorities.
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