In this July 1, 2019 photo, Wendy Padula touches the crumbling foundation of her home in Vernon, Conn. The foundation is deteriorating due to the presence of an iron sulfide known as pyrrhotite, often described as "a slow-moving disaster," which causes concrete to crack and break gradually as it becomes exposed to water and oxygen. After worrying for years about the foundations crumbling beneath their houses, hundreds of suburban homeowners in a…