All employees were ordered to evacuate around 2:00pm, Tuesday afternoon.
Tanks containing chlorine dioxide exploded in the Northeast corner of the building.
The explosion killed 48 year old James Gibson and sent 5 others to the Marion Hospital Emergency Room with non-life threatening injuries. 3 others refused treatment on the scene.
Witnesses say they heard an explosion and saw smoke coming from the building.
The plant employs more than 1600 people in multiple shifts.
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