By Karla Paris
Government officials are determining if massive fish kill was caused by chemical leak from Tyson Foods
Monett, MO is ground zero of an investigation involving Tyson Foods. On May 16, a chemical compound called Alimet, an amino acid that Tyson Foods uses as a feed ingredient for its poultry operations at the company’s feed mill in Aurora, MO reportedly spilled.
Tyson Foods workers attempted to capture the spilled compound and shipped it to its wastewater pre-treatment plant next to its poultry-processing plant in Monett, MO. 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. It is believed that the fish in Clear Creek and all of the bacteria that process the effluent (liquid waste or sewage discharged into a river or the sea) in the plant died by the injection of the chemical compound Alimet into the water system.
Monett, MO Utilities Superintendent, Skip Schaller says, “The initial shock of the Alimet hitting the plant on May 16 had a devastating impact on the bacteria that treat effluent at the plant.” Five days later, by Wednesday, May 21, the effluent began to smell bad, reports Ron Gajdos, assistant chief operator at the waste treatment plant. According to Gajdos, by the next day, “There was no life in the oxidation ditch.”
The oxidation ditch is a racetrack of about eight cells through which effluent passes. In each of the cells, bacteria help break down impurities in the effluent, including ammonia. Part of the process involves depriving the bacteria of oxygen, which prompts discharge of cleansed ammonia into the atmosphere. Without the bacteria, no process offered an alternative way to extract the ammonia, leaving the toxic substance to pass undiluted into Clear Creek. According to test results received Wednesday, May 28, ammonia levels from tests taken on May 23 reached around 20 milligrams per liter. Monett, MO's plant is licensed by the Department of Natural Resources for ammonia of about six milligrams per liter.
While still under investigation, the cause of the spill is believed to originate from a holding tank for the liquid feed product Alimet that developed a leak. Tyson Foods personnel sealed the leak, mopped up the spill, and decided to ship the spilled liquid to the Monnet, Mo plant for disposal at the wastewater pre-treatment plant. It was at the treatment facility that after about 20 minutes of unloading what was thought to be a shipment of animal fat, typically treated by the waste water plant, the operator noticed the shipment was not animal fat. The mislabeling of the materials was the gateway for the Alimet to enter the water system. A further investigation into the exact cause is underway.
Tyson Foods spokesman Worth Sparkman says, “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.”