I am having a problem with mold in the crawl space of my 5 year old house. The mold is grey in color and It is like a dry dusty mold that is on the joices only. There is no other form of mold in the crawl space and seems relatively dry. The crawl space has a sump pump that runs year around, with plastic and pea gravel as well as air vents. Can anyone help me out with how to eliminate it, or find out how to fix the problem.