I knew someone called Mel who had a hole that big.My Bullshit Detector started jumping around, moving from yellow to red the more I watched this. Paused the video and did a quick Google search, this was the take away from Wikipedia:
"According to State Department of Natural Resources geologist Jack Powell, the hole does not exist and is geologically impossible. A hole of the depth claimed "would collapse into itself under the tremendous pressure and heat from the surrounding strata," said Powell. Powell said an ordinary old mine shaft on private property was probably the inspiration for the stories, and commented that Mel's Hole had established itself as a legend "based on no evidence at all."
Thanks for posting it though, that would have been too cool if it was real.