A semi truck carrying ammonium nitrate, a highly explosive chemical used in mining, overturned this morning near Hibbing Taconite.  A mile wide evacuation effort was originally in place, but the tanker appears to not be leaking any of the chemical, just hydraulic fluid.

Spokespeople for the company confirm that the truck is owned by Dyno-Nobel Company, with which Cliffs contracts to carry materials used in their controlled mine explosions.

Roads are blocked leading into, and out of, the mine.

Ammonium nitrate is commonly used as a high–nitrogen fertilizer, and is used in 80 percent of explosives in North America.