Separate Tunnels The BorderTransportationSystem has two elevations, one for the highway or regular High-Speed Rail system and one for the Mag Lev system, and therefore if tunnels are incorporated there will have to be a separation of tracks.  Tunnels will have to be dug for each individual set of tracks or pavements.  This may require a separation of the lines, before the tunnel entry and exits, and it may require a system of water drainage for each.  Tunnels also complicate the maintenance as maintenance roads will need to be incorporated into the tunnel system.  If a maintenance worker is in a tunnel when a High-Speed or Mag Lev train enters that person will be a great risk of injury from the forward air pressure, the side turbulence, and the vacuum caused by the passing train unit.   The use of tunnels is to be avoided if possible, the use complicates the security of the system and adds much cost to the system.  It will be better to bypass a mountain or trench through it, thus keeping the configuration of the roads and tracks intact.  Index of ...