

An explosion at Wisconsin’s only oil refinery resulted in the evacuation of communities within a 3-mile radius and 10 mile corridor South of the blast location. The explosion ignited the contents of one of the refinery tanks, which created a massive amount of toxic smoke. Luckily for Lake Superior, northerly winds spread the smoke south of the refinery away from the lake.

The plume was large enough, and thick enough with particulate matter, to be captured on radar by National Weather Service Duluth:
2:15PM Radar image of smoke plume – now reaching to southern edge of Douglas county. This is tracking smoke aloft. Smoke plume may drift a bit to the west this evening. pic.twitter.com/PCFrzg4Es3
— NWS Duluth (@NWSduluth) April 26, 2018
The tank contained either crude oil or asphalt. When such oil products undergo combustion, they release gaseous chemicals and carcinogenic particulate matter. Three schools and one hospital were evacuated because of the noxious smoke.

The explosion occurred around 10am Thursday, April 26. The fire was extinguished by 11:20am but later reignited before being completely extinguished by late Thursday. The evacuation order was lifted just before 6am Friday, April 27. 11 people were injured, one with serious blast injuries.
Related: Chemical Raises Concern in Wake of Superior Refinery Explosion, Fire