Here is an old thread where someone posted a message about finding a "trap door" with some kind of vault behind it when remodeling his house on 2nd Ave. Be sure to read Woody's response.http://www.outsidelands.org/cgi-bin/mboard/stories2/thread.cgi?151,0#msgtitle
Jo Anne's post had a good point that prohibition was from 1920 - 1933. Given the large amount of sand dunes that still existed back then I have to wonder the possibility of a few "camps" that may had been set up away from any of the roads where folks could have operated a makeshift "distillery". If this was true, which one (or more) of our houses were built on top of it? Just some food for thought.