re: Anybody recall a big sinkhole that was expanding in south Louisiana years ago?

We bought some equipment off the mine site prior to & during demo of the plant on the surface. Decision to close was driven in large part by the McIlheny's deteriorating relationship with Cargill.

The flooding was to balance the forces acting (alleviate the dP) on the burden above the mine. There have been sinkholes on the island in some very visible spots for a long time. One has been having clay and sand dumped in it 5 days a week for years just to maintain a sort of ground level.