A fire at the former Vel-Donna Fertilizer Plant in Kalona Tuesday is being investigated by the State Fire Marshal’s Office. Kalona Fire Chief Steve Yotty says it’s unknown at this time what caused the wooden structure at 215 South 14th Street to catch fire. Yotty explains the building contained drums of oil. Some of that oil was released during the fire and is now contaminating the site. The building is rented by Hershberger Oil. There were no injuries. KCII will bring you more information when it becomes official.