What to do with moldy combs?   Give them to the bees to clean,
 
When I used to store my supers in plastic bags, I found that most of them
developed museum-quality mold on the combs.   The bees always cleaned them up
nicely without any subsequent problems.
 
I have since given up the practice of storing supers in plastic bags, but
mold wasn't the reason.
 
W. G. Miller
Gaithersburg, MD