PIERCE CITY, Mo. — At one point, the foul air emanating from Clear Creek near Patricia Holloway’s home was said to overwhelming.
“This started last week,” she said. “People were asking: ‘What’s going on?’ It was really that bad. We figured it had something to do with the sewer plant at Monett because the water smelled like sewer water.
“It was too strong to handle. It was enough to make your eyes tear up, it was so bad. This is not a joke. It was that bad.”
When she was told that contaminated water had caused a 100 percent fish kill in a 4.5-mile stretch of Clear Creek between Monett and Pierce City, she said: “I believe it. There’s dead fish everywhere. We saw them dying. I have lots of pictures of it.”
Holloway said she is keeping her five children away from the creek.
On May 16, an undisclosed quantity of Alimet, an amino acid compound that Tyson Foods uses as a feed ingredient for its poultry operations in the area, reportedly spilled at Tyson’s feed mill in Aurora.
Tyson workers captured most of the spilled compound and shipped it to its wastewater pre-treatment plant next to Tyson’s poultry-processing plant in Monett. Wastewater from the processing plant is pre-treated before it enters Monett’s municipal waste-treatment plant. Treated water from that plant flows into Clear Creek and is responsible for most of the flow in the creek.
The introduction of the chemical caused “a 100 percent kill” of the bacteria that process the effluent in Monett’s wastewater plant, according to Skip Schaller, utilities superintendent at Monett.
“It short-circuited the plant,” he said.
That bacterial die-off, which involved 15 million to 20 million gallons of water in the plant, caused a foul, sulfur-like odor to develop over Monett on or about May 21 that lingered for days.
Schaller said Alimet, because of its extremely low pH level, is not something that can be treated by Monett’s plant. The plant’s operators were not informed by Tyson that the chemical was being introduced into their system, he said.
As effluent passes through the plant, the bacteria stimulate the release of ammonia as a gas into the atmosphere. The elimination of the bacteria in the treatment plant created a slug of virtually undiluted ammonia that entered Clear Creek, killing virtually all of the aquatic life in the stream between Monett and Pierce City, according Adam Boman, who is leading an investigation into the fish kill for the Missouri Department of Conservation.
“It’s a complete kill between Monett and Pierce City, and a partial kill after Pierce City because of springs that are diluting whatever it is that is killing the fish,” he said. “We are talking about thousands of fish.”
Clear Creek is a tributary to Shoal Creek, a source of municipal water for Neosho and Joplin.