A second fire broke out at the Mosaic phosphate plant in Riverview on Tuesday after the first fire was put out only a day before. The Hillsborough County Fire Rescue said they arrived at the plant at 8813 US Highway 41 in Riverview around 10:36 a.m. According to officials, the extreme heat of yesterday's fire, coupled with the wind conditions, caused a brush fire to break out at the same location. They added that one of the polyethylene pipes is involved, but it doesn't threaten any structures. Crews have extinguished the fires but are still working to put out hotspots.