Hello all...first time here and am just starting to poke around at the idea of building an underground shelter. I currently have a nice little log cabin tucked away in the woods with a fresh, spring fed stream running behind it. Sits on 40 acres with thousands of acres of state land behind it. The stream runs through a pretty steep valley sitting about 15ft below the cabin. It serves as a nice hunting cabin but I am looking into building something more secure for my family in case things ever take a turn for the worse. I would love to get some advice on where/what to look for to get this built. Here are some thoughts: Electric supplied by the stream...figured it has a 8ft. head (of pressure?) Fresh water by way of a well. Space for my family (wife, 4 kids, and room for a few others) Ample storage for food, supplies, etc. Radiation resistant Fully secured against intruders Air filtration Off the grid living basically Above all else, I want this to be almost 100% hidden from the outside world and able to support us for at least 1 year. I would like to budget around $50,000 or so accomplish all this. Any help would be great! Thanks!