Uncovering the pallets gave way to the mysterious water retention problem in the deck! We raised all the pallets and left them to dry in the sunshine. The pallets were layered with a sort of black plastic material and there were several layers of them, that were causing all the water retention since most of the water was not flowing out into the drainage. As you can see the deck’s wooden pallets have started rotting (some of them) and the white yucky looking deposit is god-knows-what from another planet! Everytime I look at them, I want to pressure wash the heck out of them and make them the clean and smooth looking wood pieces God intended them to be.