Photo: Aldrich, Beatrice (uploader)
(Marengo, IA) -- The State Fire Marshal is declaring the fire and explosion at a biofuels plant in Marengo as accidental.
The explosion and fire at C6-Zero on December 8th led to a dozen injuries and forced nearby areas to evacuate.
The report from the State Fire Marshal says an unknown mechanical failure ignited flammable air vapor at the plant.
C6-Zero was dissolving used roofing shingles where the chemical process made flammable vapors.
The investigation is considered closed unless further information comes out.