Two things if I may NECVOL. While I personally think you should have put the cave underground, your description of how it's built seems pretty solid. Seems it would be ideal to use as a safe room as well.
Second thing is the reason I aaid I hope your cave never, ever gets tested is because of Oklahoma. That was the year if I recall right Timothy McVeigh bombed a federal building. They had an EF-5 Tornado and I was due to give a presentation to bunch of school officals and state reps, teachers, and students. The day prior to that a friend gave me a tour of the tornado damage. I swear some places looked like the WWII atomic bombing of Japan. What impressed me most was a string of car dealerships. One was damaged, the next heavily damaged, and the next site looked as if someone had taken a vacuum cleaner to it. No building, no cars, just a square shape of ground looking so clean you might want to eat off it. I had and since then have never seen anything remotely like that. Trucks wrapped around phone poles. Cars crushed as if a giant fist had crumbled them like paper. Entire buildings (apartments?) ripped inpieces and flipped on their side. I just sat there in the car, mouth wide, couldn't say a thing. You see that stuff on TV but it can't compare with the real on site view. Mom Nature just don't give a dayum about about the works of man or any claims of invincibility. So when I say I hope your beautiful cave is never tested, I mean it. I've seen what the baytch can do and that wasn't even an earthquake, hurricane, or tsunami. Beyond that, love the picturs and how you laid out the place. It's truly Vol-heaven. May it give you years upon years of pleasure and develop a supernatural power where the Vols win each time you venture into that cave to watch a Vols game. Or simply go inside to take a nap.
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