posted on Jun, 8 2011 @ 04:50 AM
Wow, time to inject some actual knowledge into this discussion. Here's some facts:
Underground drilling (boring) machines exist and are being used today, they were famously used to construct the
. The only lasers they employ are used for guidance, I'm afraid the actual carving
mechanism is far less sophisticated, sorry sci-fi fans. The head of the drill rotates, grinding the rock up where it then falls to a collection funnel
and is whisked back out the other end by conveyor belts. No "melting of rock to coat the tunnel walls". Science to the rescue: the melted rock would
be less dense than its solid counterpart, taking up more volume when molten. If it was used to coat the walls there wouldn't be a tunnel as there
would be an excess of molten rock.
Also, the mention of sinkholes and the water table are irrelevant and here's why. Sinkholes are caused by voids beneath the surface of the earth,
usually from the movement of water. The catch is, they only happen in soil. These tunneling machines would be creating tunnels in the bedrock, far
below both the overlying soil and the water table. And yes I know seepage occurs even in bedrock, but it is mitigated in these tunnels by using grout,
shotcrete, and pumps.
As mentioned earlier, this is 25+ year old technology. Even with limited use, they could dig a whole lot of tunnels in 25 years.