How about the explosives remaining somewhere in the town (YOUSEFIYA) where Al Qaqaa is located. See my post #117.
As of May of this year, the people of the town are reported to be hostile toward our troops. 400 to 500 lb bomb found there.
Possible, but not probable. Thats a lot of stuff to hide, and would require a large area to hide it in.
We prolly have already run across this stuff without the UN seals attached and didn't know it. And likely have already made it go boom in a big way. The engineers have been getting lots of practice in munitions destruction.