According to the project drawings (which can be viewed here:
https://www.commbuys.com/bso/external/b ... entUrl=bid" onclick="window.open(this.href);return false; ) only stairwell 5 will be reopened and stairwell 6 will be capped over. The elevator landing in the tunnel will be in the middle of the tunnel directly across from stairwell 5 unlike what was done for the current platform D entrance where the elevator was built where the second stairwell originally was. If you visit the station now the area around stairwell 5 and the new elevator area is walled off with temporary partitions while former stairwell 6 was covered over by a permanent sheetrock wall. The two egress ramps are on each end of the high level platform and go down to grade level to the paved walkways that currently cross the tracks. These ramps will have gates on them and be for emergency exit and employee use only. I'm guessing these were required because they are only restoring one tunnel stairwell and to meet regulations need to be able to accommodate a worst case situation where full trains parked at the platform need to be evacuated. This would also provide an alternative route for employees to assist passengers with mobility needs or in wheelchairs if the platform C elevator is out of commission via either the platform D elevator or the Union Station rear elevator.