The disaster occurred when workers were ordered to dig illegally under the Susquehanna River without proper safety precautions, creating a hole in the riverbed which caused the river to flood into the many interconnected mine galleries in the Wyoming Valley between the right-bank (western shore) town of Exeter, Pennsylvania, and the left-bank (eastern shore) town of Port Griffith in Jenkins Township, near Pittston. Twelve miners were killed. Plugging the hole in the riverbed took three days, and mitigation efforts created several new islands between the two towns and altered the western-side flow of the Susquehanna around these.
The coal industry in northeastern Pennsylvania had already been in decline at the time of the accident as fuel oil and natural gas became more popular forms of energy. Congrats to John Galt? And Alygator05 for the FTF