Creeping along at 12 MPH, this testing special is about to disappear into the west portal of the Moffat Tunnel. The train will stop at East Portal, wait for the tunnel to vent, and return west through the tunnel. The green pipe to the left leads to the Moffat Water Tunnel. Built at the same time as the train tunnel, the water tunnel carries water from the west slope of the Continental Divide east to Denver.