GREEN BAY (NBC 26) — General Mills, which owns TNT Crust, tells NBC 26 the plant "will resume operations" following an ammonia leak in Green Bay early Wednesday morning.
The ammonia leak at the plant prompted an evacuation at around 1:15 a.m. Upon arrival, a substantial leak in the ammonia coolant system was found.
The fire department said plant employees were evacuated with a total of six people being evaluated or transported for respiratory issues. Three people were taken to local emergency departments and three other people were treated and released at the scene.
"Everybody that was transported is OK, and released from the hospital," Green Bay Metro Fire Department Battalion Chief and HAZMAT leader Mike Vanden Avond said.
Vanden Avond says he is not sure what caused the ammonia to leak, but knows that it took place in one of the production areas of the plant.
TNT Crust cools its products using an ammonia system.
"They're prevalent throughout the city for any cold storage," Vanden Avond said.
Ammonia is a colorless gas with a very strong smell.
"It's an asphyxiant," Vanden Avond said.
Meaning it can be harmful to the body.
"It's pretty uncomfortable when you inhale it at high concentrations," UW-Madison Department of Mechanical Engineering professor Douglas Reindl said. "I mean it creates basically a chemical burn. I mean that's what it has the potential to do."
Reindl says ammonia does not trigger global warming or drain the ozone layer.
"That's a facet of ammonia that has been known as an advantage for some period of time," Reindl said.
He says plants use ammonia as a refrigerant because it works well in a wide variety of working conditions.
"These plants have used it historically," Reindl said. "And there really hasn't been a compelling reason for them to transition to something else."
"So I take that ammonia leaks in plants or facilities like this are kind of rare," reporter Tyler Job asked.
"The ones that have the effect of sending people to the hospital are pretty rare," Reindl said.
The Brown County Hazardous materials Team responded to assist with the investigation and air quality monitoring, the fire department said. The leak was controlled and the building was ventilated and turned over to TNT Crust Maintenance Department for repairs.
Assisting agencies included the Green Bay Police Department, the Department of Public Works, and the Brown County Hazardous Materials Response Team.
Below is the full statement from General Mills:
"Early this morning, our Green Bay, Wis., facility experienced an ammonia leak that was quickly controlled by the Green Bay Metro Fire Department and Hazardous Materials Team. The safety of employees is always our top priority, and the building was temporarily evacuated, ventilated, and inspected. Having been given the all clear from local officials, Green Bay employees will resume operations."