I am working on a project at which there has been some settling and sinking of the surface. After all of our investigations we beleive that it may all be caused by some sort of wildlife activity and the collapse of burrows. It looks like there is woodchuch activity at the area due to the precense of an entrance to a summer burrow, however, this entrance is on a side-slope at a lower elevation than where several long "trench-like" collapses have occured at our site. I guess my question is, would it be possible/typical for woodchuck burrows to extend a great distance (over 100-feet) from the entrance and to collapse at some time? Thanks.