#99closure feature: Removing soil from the tunnel
More than 850,000 cubic yards of soil will be removed from the ground during the course of tunneling. To put that in perspective, imagine this: If you piled that soil on the turf at nearby CenturyLink Field, the pile would be about 400 feet tall – more than 100 feet taller than the stadium’s roof.
Excavated soil travels via conveyor belt from the front of the tunneling machine to a barge waiting at the north end of Terminal 46. When the barge is full, it travels across Puget Sound to CalPortland’s Mats Mats reclamation facility at Port Ludlow, where the material is being used to help fill an old gravel quarry.
One barge can carry up to four rings worth of soil, or the equivalent of 160 truckloads.
You can watch STP’s barging operation on our construction cameras.