The Reaction of Embankment to Longwall Mining Subsidence

Over the last 50 years, full extraction longwall mining has become an efficient and safer means to remove coal from underground deposits. When enough coal is extracted, a subsidence basin forms on the surface, which causes the ground to drop and induces strains and deformations on the surface. In the winter of 2019, a longwall panel that averaged a depth of 675-ft undermined a section of Interstate 70 (I-70) in Pennsylvania, causing as much as 5-ft of vertical subsidence. As the highway was undermined, the pavement, slopes, and embankments were monitored for signs of failure using regular surveys, instruments, and observations.