That isn't very efficient. I believe the Seattle downtown project, along Alaska Blvd. used one. In Portland they used one, decades ago, to bore 2 miles +/- of subway. Personally I think the story is possible. When I was young it was not uncommon to see long military convoys on the highways and 100 car trains carrying military equipment. Those disappeared decades ago. Did they stop transporting military equipment? I have never seen any equipment entering McCord AFB.