white paper basement water
https://page-wiki.win/index.php/White_Paper_Basement_Water:_A_Practical_Guide_to_Keeping_Your_Basement_Dry
You're in a musty basement with a white paper that's been left on the concrete floor near a sump pump. The edges are starting to curl and darken as moisture wicks upward, turning the crisp sheet into a damp, warped mess that smells like wet limestone and old pipes.