Representatives from TransCanada were in Port Edward on Dec. 9 to give an update on the pipeline, with much of the focus being put on the underwater portion of the project.
The company will be running two 36-inch pipelines, which are concrete-weight coated to endure the pressure of being hundreds of metres below the surface, from the Nass Valley to the Pacific NorthWest LNG terminal on Lelu Island using a specialized 330 metre long vessel.
“The whole process for the marine pipeline will take about a year, the actual heavy construction, where we are constructing pipe and laying it on the seabed will take about four months. All the rest is smaller activities such as doing seabed preparation at the front end and working on the pipeline at the back end,” said major projects director Neil Milne.
“Laying a large pipeline like this underwater, this is the first one for us. But all of the contractors involved have done this thousands of times … there are only about four companies in the world that do this type of pipelining and have the type of vessels that can lay the pipe. We’re reviewing their bids at the moment and will have them selected by early January.”
The pipe will be laid at an average depth of 250 metres, with open ocean depths ranging from 80 metres to more than 600 metres. While the pipes won’t be buried in the open water, TransCanada said it is taking extra precautions when it comes to the area near the terminal.
“The soils outside of Lelu Island, the first couple metres are pretty soft. It’s almost flaky soil so there is not really sediment, but down below that it is reasonable soil for trenching a burying the pipes,” said Milne.
“It doesn’t need to be from an engineering perspective, we’re just doing it so fishing gear doesn’t snag on it. Not that it would because it is concrete-weight coated, but we’re going to bury it so the seabed looks like its original state. We won’t be burying it in the deep ocean.”
To accommodate the people laying the pipe, TransCanada will be using a work camp unlike any other proposed for the North Coast.
“There will be a marine camp that we will have to use, which we didn’t have in our environmental application … the land is too rocky and too mountainous to make a camp at the entry point, so it is easier to float a camp in,” said Milne.
“It is a 400-person camp. Our camp and all of our vessels will be zero discharge, so all the waste will either be taken back with them or brought to a plant for processing.”
In terms of the workforce, Milne said all four contractors are required “to have a commitment to use local resources and local people and supplies where possible”.