FORT ST. JOHN, B.C. – BC Hydro says that remediation work will begin today on the 400-metre tension crack that occurred back in February at Site C.
The two-stage remediation plan will be executed by BC Hydro and its contractor. The construction of a toe berm will begin which will make the area stable. This should be completed by late March.
When the toe beam is completed, it will allow the second stage of the remediation plan to commence. The second stage will focus on removing the material from the north bank and allow work to continue.
BC Hydro says they have conducted tests and found that the slope around the crack is stable.
“Safety is our top priority. Over the past week, BC Hydro’s design and safety teams and technical experts in slope stability have been undertaking geotechnical assessments. Monitoring instruments, including survey prisms and inclinometers, have shown that the slope around the crack is stable. In addition, drilling equipment was used to drill and install additional instruments to gain a more detailed understanding of the crack, which informed the remediation plan.”
The company expects to complete the remediation work for the crack within the overall project budget and schedule.
Work to remove soil has been ongoing for a long period of time according to a statement sent out by BC Hydro. They say cracks like this are not uncommon but because of the size of this particular tension crack, it required attention.
“As part of Site C construction, work has been underway for the past 19 months to remove unstable soil to create stable slopes for eventual dam construction. During the construction of a haul road to support this excavation work, a tension crack appeared. Tension cracks are not unexpected in this area; however, this particular crack requires attention due to its significant 400-metre length.
While there was some initial movement of soil, it has now stabilized. This area of unstable soil was already slated to be removed as part of engineering new stable banks for dam construction.”