The town of Daisetta, Texas sits happily upon a salt dome. Unfortunately, this means that it is at risk for sinkhole formation. In 2008, a sinkhole opened up and swallowed some construction equipment and part of a facility.
It eventually filled in with water and formed a gross looking lake.
You can find it yourself on Google Earth using these coords: 30°07'15.19"N 94°38'51.26"W