We recently bought a home built in 2004. During the inspection it was noted that there is what is assumed to be pressure treated wood "band board"or a ledger board (?)at the rear of the home adjacent to a patio. The house has a crawl space. There is masonry foundation in the front and sides of the house, but in the rear there is this two feet of treated wood buried with a few inches above ground. Should we excavate the area where the wood makes contact with the ground and waterproof? Should we replace with masonry? There is NO water currently going into the crawl space, but rain regularly flows towards this area.