The shape of prime base

[dragoon500ly]

We have two basic problems with using TBMs or abandoned mines, etc..

Security is the biggest. An abandoned facility, being a mine, old factory, hyperloop etc., is that there are people AND documentation that shows its location. It would require a major cover operation to deflect attention away. Using a mine, for example, means that both Federal and State organizations have to be convinced that the mine is no longer their concern...and this includes convincing the EPA that there are no hazardous chemicals remaining on site.

Second problem is the footprint of the excavations. Spoil. hundreds if not thousands of tons of it. Its got to go somewhere. Calling it a mine brings the Feds/States into the middle of it. Calling it a "Nuclear Waste Disposal Site" will certainly get several Federal agencies into the loop. And a lot of them are going to want on-site inspections. Which leads us right back into the Security concern(s).

Because of these concerns, I'm not convinced that a TBM is the best approach. Rather, what is needed is something that can bore the tunnels, rapidly, discreetly, and be able to dispose of the spoil. We already have a Project with fusion power and lasers, perhaps a laser boring machine...yet another "handwaveium"?