I believe some sailor dude lost a coin in the pit under the outhouse trying to pull his pants over his peg leg. They found the pit and the coin and dug through tons of crap to get there.
I watched part of one episode and decided that they hadn't found and would never find anything there. I wish it were real, but...
They have found the money pit. They look into it every day. The hole they dug IS the pit. It has taken a ton of money to dig the pit. Ever seen the movie the Money Pit? Its about a remodel job that they sink all their money into.