A chemical spill Monday morning at a wastewater treatment plant in Madison prompted a portion of the facility to be evacuated.
Mike Simon, the plant's assistant chief engineer, says chemicals being delivered to the facility were accidentally placed in the wrong vessel. The mixture of two chemicals resulted in the release of chlorine gas, which can be fatal if inhaled.
Two people were treated as a result of the incident, although Simon says it was mainly so officials could "check them over."
AUDIO: Mike Simon, Madison wastewater treatment plant (MP3 :15)