BEACH PARK, Ill. — Federal investigators say open valves on farm fertilizer tanks apparently led to a serious ammonia leak that injured 41 people in Lake County Illinois in April.
The National Transportation Safety Board released a preliminary report on the anhydrous ammonia spill in Beach Park, Illinois, near the Wisconsin border. Anhydrous ammonia is a colorless gas used as an agricultural fertilizer that produces pungent, suffocating fumes when released.
The NTSB says a hazardous-materials team from Lake Forest, Illinois, found some valves were fully open on a pair of 1,000-gallon tanks, which were being pulled by a tractor. The ammonia release stopped when a valve was closed. Investigators plan to examine the valves at a laboratory in Washington.
The NTSB says the loaded tanks were picked up at a farm cooperative in Kansasville, about 30 miles from the accident scene.
At about 4:25 a.m. on April 25, a large release of anhydrous ammonia occurred on Green Bay Road at Clarendon Street in Beach Park, about 24 miles south of Racine.
A tractor driver, a Sturtevant man, was towing tanks of anhydrous ammonia from Pleasant Prairie to an Illinois farm when the chemical leaked, creating a toxic gas cloud.
A shelter-in-place order was issued for residents within a 1-mile radius of the leak.
The plume released by the anhydrous ammonia spill affected residents of Beach Park, Wadsworth and Zion, as well as people traveling through the area.
Throughout the morning, emergency crews conducted door-to-door wellness checks, evaluating and treating residents as needed. About 40 people were transported via ambulance to local hospitals.