Problems with the Left Bank at Site C

The amazing thing about civil suits is that they tend to bring documents to the light of day that may otherwise never be exposed. Until a determination of their civil claim for Treaty infringement can be determined at trial, West Moberly First Nations have filed an application for an interim injunction to suspend construction on the Site C dam. In that application, we came across the following document:

Site C Clean Energy Project - Conditional Water Licences 132990 & 132991 Leave to Construct LTC #01G - Left Bank Excavation Phase 2 Recommendation for Amendment #6 - Redesign of Left Bank Excavation

(Affidavit #1 of Robert McCullough see pages 548 to 551)

This is a letter dated December 9, 2017 from an Independent Engineer on the Site C project about changes that are required to the left bank (north) excavation at the dam site. The tension cracks from spring 2017 and their resulting “stabilization measures and local revisions” are mentioned, and so is other multiple revisions to this slope. However, it is not revealed exactly why more work is needed, but it clearly states that “more extensive revisions are proposed to the design and construction approach for left bank works” What does that mean? Well, among other things, it means: “The revised design will increase the volume of Class 1 (overburden) excavation by about 2.35 M m3, resulting in an approximate total quantity of Class 1 excavation of about 11.1 M m3.”

This is a very big deal. This is major earthworks that are much in excess of the original plan to stabilize the Left Bank. This is directly above the location of the proposed diversion tunnels that are required for the dam to be built. We are told this is Amendment #6, which suggest that they continue to make new amendments as previous efforts fail. Furthermore, the letter leaves the door open for “further proposed design revisions”.

This work extends up slope to where they are now encroaching on the very expensive camp structures in an attempt to stabilize the slopes. This area is somewhat visible from the BC Hydro viewpoint, and from our observations taken on February 28, it appears they have removed the fence on the south/west side of the office structures to facilitate new excavation work. In short, they are running out of room to deal with this slope as indicated in the letter: “The top of the excavation will be set back by up to about 30 m/ which will encroach on the existing access road to the BC Hydro site office building/ a portion of the existing parking lot on the south side of the worker camp/ and a portion of the ATCO water pipeline. These non-LTC facilities will be redesigned and/or relocated as required, in a local portion of the upper excavation near the access road to the BC Hydro office, soil reinforcement will be installed to allow construction of a steeper slope to minimize the extent of the enlarged excavation.” In other words, new infrastructure built for the camp and offices is now in the way and being impacted. It is not explained what is intended for “soil reinforcement will be installed”.

It should be noted some of the material being excavated is now being dumped immediately adjacent to the BC Hydro viewpoint in an area that was never intended for that purpose. While the ‘view’ from there was designed to be very limited, it is now getting worse!

The dates given are somewhat curious. There was a site visit on December 7, 2017, followed very quickly by this December 9, 2017 document signed by an Independent Engineer. That seems like a very fast turnaround on such a major issue, and just two days before Premier John Horgan announced that Site C would proceed. In that announcement, he stated that he was “…advised that we have passed those issues” when ask about the geotechnical problems at Site C.

Amendment #6 seems pretty dubious, and very expensive. Was it part of that geotechnical reassurance and price jump to $10.7 billion in John Horgan’s announcement?

Regards,

Ken Boon