I read somewhere about cooking soil in the oven to kill parasites. It's supposed to stink, but if it works...
Anywho, I'd be more worried about pollutants, does the neighborhood have access to this pond? Is it anywhere near sewers? If there's poison in the water it'll be in the mud too.
Black soil sounds fertile though. *waggles eyebrows* I'd give it a shot. Just PH it and everything first!