The DNR is investigating a fertilizer spill that occurred Thursday in the Butler County seat of Allison.
An employee of the Farmers Cooperative in Allison was pulling a tank of 32 percent liquid nitrogen fertilizer when a seam on the tank failed. About 800 gallons of the fertilizer spilled on a city street. Without reporting the spill to the DNR, employees decided to wash the spilled liquid into a storm sewer.
The DNR was notified Friday, 26 hours after the spill. DNR staff advised co-op to flush the storm sewer with water and pump up the mix of water and fertilizer, to prevent additional fertilizer from reaching a nearby stream. They were also asked to soak up liquids standing on the street.
When the DNR staff arrived Friday afternoon, they found dead minnows for about one-half mile downstream of the storm sewer. Initial water sampling over the eight-mile stretch of stream to the West Fork of Cedar River showed elevated levels of ammonia in spots, but ammonia levels dropped significantly over the next three days. By Monday afternoon, no additional dead fish had been found.
Saturday the DNR staff asked the co-op to build a dam across a drainage ditch south of Allison to collect additional contaminated water. By early Monday afternoon, the co-op had recovered about 42,000 gallons of the water-fertilizer mix.
The DNR will continue to monitor the cleanup and consider appropriate enforcement actions.
For more information, contact Trent Lambert at 641-424-4073 or Trent.Lambert@dnr.iowa.gov.