Howdy friends. Search the threads, and of the many variations on the question "why does my Prius smell?", this was not one I could find. I had a 5-gallon water bottle dump over in the way-back. The cap leaked and emptied about 2 gallons. The weathertech caught most. When the smell began, I pulled the mat, the carpet-ed floor boards (no smell), the cargo tub (no water, no smell), and then the spare kit (tools, spare, styrofoam spacer) and found the source: schmutz/debris underneat the spare had soaked up the water and fermented. I vacuumed out the schmutz, washed the entire well with hot bleach, dried it, then left the hatch open for the hot AF Tennessee sun to finish the job. Did the same with all of the parts of the spare kit. The smell is largely diminished, but lingers in the material on the floor of the well (looks like Dynamat). Has this happened to anyone else? Do I need to replace that material? And if so, is there any way other than a blowtorch to get that stuff out? Thanks all.