The spill was discovered about 6:30 a.m. when staff at the Gavilon Grain company found 32 percent liquid nitrogen fertilizer had overflowed from above-ground storage tanks near 1200 Kerper Boulevard.
The company reported the release occurred when a pump was left running as fertilizer was offloaded from a barge. They estimate as much as 1 million gallons of fertilizer may have spilled with most contained onsite. Some may have flowed into the 16th Street retention basin.
Some fertilizer ran across Kerper Boulevard near Purina Drive. Gavilon staff, the Dubuque Fire Department and Hazmat responded. The fire department closed the street and placed sand over spilled fertilizer to aid in cleanup.
DNR staff are on site, checking to ensure the leak is contained and looking for environmental impacts. As of 10:30 a.m. there was no sign of a fish kill. DNR will monitor the cleanup and consider appropriate enforcement action.