State officials are investigating to determine if a massive fish kill and a bad odor that hung over a southwest Missouri town was caused by a chemical from a Tyson Foods plant.
The Missouri Department of Conservation and the Department of Natural Resources are conducting a joint investigation into the incident, which began May 16 when a chemical compound called Alimet, a feed ingredient, was spilled at Tyson’s feed mill in Aurora, Mo.
Workers captured most of the chemical, but some made it into the wastewater treatment plant in Monett.
Skip Schaller, Monett’s utilities superintendent, said the chemical killed the bacteria that the plant used to treat wastewater, allowing contaminated water to flow into Clear Creek.
The bacterial disintegration created mostly undiluted ammonia that caused a foul odor around Monett for several days. The smell had mostly dissipated this week, Schaller said, and the wastewater plant in Monett was beginning to operate properly.
The ammonia killed virtually all aquatic life in the stream between Monett and Pierce City, said Adam Borman, who is leading the investigation for the Conservation Department.
“We’re talking about thousands of fish,” he said.
Tyson Foods spokesman Worth Sparkman said in a statement: “We’re working cooperatively with city and state officials as they investigate this matter. We’re awaiting additional details so we can understand if our operations played a role in what happened.”
Schaller said the incident proved that Monett needs to tighten some of its controls and procedures.