Quicksand Fans

Greetings from the old dominion!

Does anyone here know of any spots around central VA to go sinking? I've looked all around the James river, but most places are too heavily populated. Any ideas?

There used to be quarries with mud around Richmond but the exact locations were never disclosed by those that knew where they were. There is a quarry in Berkley Springs, WV. It definitely had mud in the past and from the Google satellite view, it looks like it still does.