Crews are investigating what caused a fire at the Deer Track Park landfill near Johnson Creek Monday afternoon. Capt. Craig Cahill with the Johnson Creek Fire Department said the fire broke out around 1 p.m. The fire covered an area roughly two acres in size, he said. Firefighters were able to extinguish the flames in roughly an hour. At 1:30 p.m., a Wisconsin Department of Transportation traffic camera on nearby Interstate 94 showed gray smoke billowing from the site. Interstate traffic did not appear to be impacted.