joseburr wrote:
“I can understand that. I forget which link—one has a map of the tunnels purportedly going all over the USA. Guessing they would equal 3-5 times back & forth coast to coast. Wouldn’t that require a lot of propane & oxygen at a minimum?”
Where did the diggers hide the dirt????
There have been a variety of very effective ways to do that. But it’s not of particular interest, to me.