In 1980, a Texaco oil rig was drilling for petroleum at Lake Peigneur, a Louisiana lake that sits directly on top of a salt mine, and has an average depth of six feet. Were it a swimming pool, it wouldn't have been safe for diving, so it probably wasn't surprising to anyone but the drillers when they punched a hole through the top of the mine.
At first the water simply trickled down below. But as the salt dissolved the hole expanded, and by lunch time they'd created a whirlpool that managed to suck the drilling platform, several barges and 65 or so acres of land into the lake. Because the water was going into the mine faster than the air could get out, spectators were treated to a geyser of water and debris that shot 400 feet into the air.
Fortunately no workers were killed by the whirlpool. Those on the platform, while unable to do their job properly, were smart enough to haul ass when things started getting a little too real, as were the salt miners below.
Probably something like this.