Do you know if there is any information on the pumping online?Aparantly they sold off every vehicle on site a few years ago including that shunter. How reliable this is I do not know.
As for the tunnel to the Jeti the entrance is in the base of the conveyor from the A frame shed. It was always flooded and had pumps running 24/7 and sometimes the Fir brigade pumping it. So with it bwing shut and for so long it will most deffo be flooded.