The Phobos Labs is one of the Main Facilitys in Site 1. It houses many technology.
Sector 1 houses it's own Teleporter. This teleporter can take you all the way to the Delta Complex, located above Site 3. The rest of Sector 1 has Warehouses and Controls for the Complex.
Sector 2 contains Site 1's two main machines: The Pump Station, and Some Colitant Rods.
Sector 3 houses the Main Plasma Reactor which powers up Site 1, and the Life Support systems.