I chanced upon this article while reading a screenplay review. The screenplay's fictional mine continued to burn to keep the monsters out, but I don't think anything can equal the horror of this one sentence from the Wikipedia article:

"Statewide attention to the fire began to increase, culminating in 1981 when 12-year-old resident Todd Domboski fell into a subsidence four feet wide by 150 feet (46 m) deep that suddenly opened beneath his feet in a backyard."

<shudder>