What to do with a toxic freezer?

So I bought a house and found a non-working freezer full of toxic sludge.....the remains of the food that was in it. I can't take it to the dump because of CFC release, They have an appliance drop off, but they have to be clean. Does anyone have any idea how I can get rid of it? (aside from just dumping it somewhere, I really DON'T want to do that) By the way it stinks soooo bad that you can hardly stand to open it, much less clean it out.