Chipmunks have burrowed under above ground pool causing liner to indent over their burrow. How do I stop further erosion under liner?
Get rid of the chipmunks. The liner stretches to drop into depression. If it stretches too much ,it will have a small leak. This mobilizes the soil to sink further; not leading to a happy ending ( been there, done that). I think the only practical repair is a new liner and fill any low spots before installing it.