Deer Run Mine informed the Montgomery County Emergency Management Agency (EMA)  that the last planned subsidence (a sinking or collapse of the ground surface) had begun. The message specifically advises motorists traveling on Illinois Route 185 to use caution, reduce speeds, and be aware of the posted signs along the route. The area impacted is said to be the length of a football field  by the new substation before going down the hill.  The mine authorities clarified that despite the ongoing subsidence activity, Illinois Route 185 will remain open for traffic, though drivers should stay vigilant and follow any instructions given through the signs.