Help! Mold Smell on Rug Pad

I made sure our Christmas tree really lasted this year-watered the heck out of that thing. Apparently that water also leaked onto the rug underneath the tree and soaked into the rug/carpet pad underneath. When I took the tree down, I spilled a bunch of water so I moved the rug/carpet pad back and noticed white on my hardwood floor and a mold smell/white on the pad. I pulled the pad and rug back past the point of any spills, then I wiped the area down with Murphy's oil soap and mopped it with a swiffer wood mop. I can still smell it faintly. Can I put bleach on the rug pad? It's a large rug--at least 9x6--so I don't want to pay for a new pad if I don't have to. I would say put the whole thing out in the sunlight but we are having lots of much needed snow storms here so that isn't an option right now!

What ideas do you have?

I would try hanging the pad over a shower curtain rod to thoroughly dry it out. If you still smell mold after several days, try spraying it with hydrogen peroxide.

Thanks! I think I will have to do that next weekend.