A major milestone has been achieved in the US-$473 million project to complete the second tunnel at Rio Tinto’s power generation facility outside Kitimat.
The massive 150 ton cutter head of the tunnel boring machine (TBM) called tl’ughus that will complete the 7.6km second tunnel (T2) was pulled to the face of the new tunnel in the early hours of January 17.
With the cutter head now in place, work can begin on bringing the rest of the TBM into the starter tunnel.
Once fully assembled tl’ughus will reach 195 metres in length and will simultaneously bore and line the new tunnel at a speed of up to 16 metres per day.
Over the next two years or so, tl’ughus will slowly make its way east from the Horetzky Landing to Tahtsa Lake, carving with precision, a new tunnel parallel to the original nearly 65-year old tunnel. The new tunnel will operate in concert with the original tunnel, bringing water from the Nechako Reservoir to the Kemano Powerhouse.
There are currently over 250 people working on site and already 18km of road has been built to complete the project.
“We chose the name tl’ughus for our TBM after the legendary beast of Cheslatta-Carrier Nation lore,” said B.C. Works communication manager Kevin Dobbin. “Legend has it that tl’ughus was a giant snake that bored through mountains to get from lake to lake in the region.”
The workforce is being accommodated at a 140-person camp at Kemano and in a camp at the Horetzky landing (situated above ground halfway along the tunnel).
The second tunnel project is expected to be completed by 2020 and will ensure Rio Tinto BC Works has a stable, long-term power supply for the Kitimat smelter, creating a back-up for the original tunnel that was built over 60 years ago.
“This will allow us to conduct maintenance work without shutting down our operations, ensuring we can continue to responsibly manage the Nechako Watershed reservoir system,” added Dobbin.
The second tunnel will connect to the existing power station with no new generators being built and won’t draw any more water than what is currently allocated in the company’s water licence.
“Some minor work at the existing T2 intake will also be completed during the summer of 2019. The schedule is to have the project completed before the end of 2020,” said Dobbin.