JAY, Maine (WABI) Four contractors in Jay were taken to a hospital after a gas sensor detected a release of chlorine dioxide inside the Verso mill.
Employees were evacuated around 9:30 Wednesday morning out of precaution.
There were no injuries to employees.
The release of the chemical occurred when a valve was left open as the mill transitioned from unbleached to bleached paper grade.
The valve was closed when the gas was detected.
The air in the mill was tested and given the all clear, letting employees to return to work.