We area about 50% complete with digging our Upper Water Pond. The soil has been 100% course grain sand all the way down to 1.9 meters/ 6 feet. I dug a post hole digger 4 more feet for a test hoel and still 100% sand. 

  So after the pond is dug.. we will be lining the pond with a 10 mil Polyethelyne pond liner placed over vegetative matter to form a Gleyosol seal, and then cover that with 6 inches of sand. This will test the theories regarding Gleying and pond sealing and the ability of a cheap Polyethelyne liner to hold water.