[SunkenCiv]

There’s no mine under this Chilean pond, but obviously there’s some kind of cavern or crevice involved. More along the lines of the Louisiana story — during the digging of one of the tunnels in NY, 70 or 80 years ago, the crew wound getting killed when the river broke through and flooded it.

[Revelation 911]

here in western NY - the atzko (sp) salt mine was using too widely spaced pillars - all was well until the aquifer broke through and caused a huge subsidence and a 2. something tremor - no lives lost - but the mine was a loss

info here