Editor, The News:
In the recently released Mount Polley investigative report, which was charged with the responsibility of finding why Imperial Metals Mine’s and the Mount Polly tailings dam failed with catastrophic results, dumping millions of tonnes of toxic waste into Quesnel Lake, I have some observations here.
The report summaries thusly, and said “the [dam’s] design failed to take into account the complexity of the instability of underlying glacial and pre-glacial layers under the retaining wall. But the authors, geotechnicians Norbert Morganstern and Steve Vick, did not blame provincial inspectors for not detecting the problem beforehand. The investigators said the dam was built on a weak layer of glacial deposits that was undetected at the time, making the dam like a “loaded gun.”
This report goes on to say: “The panel concluded that the dominant contribution to the failure resides in the design. The design did not take into account the complexity of the sub-glacial and pre-glacial geological environment associated with the perimeter embankment foundation. As a result, foundation investigations and associated site characterization failed to identify a continuous GLU layer in the vicinity of the breach and to recognize that it was susceptible to undrained failure when subject to the stresses associated with the embankment.”
However, the panel did not point the smoking gun at government as, on site government inspections would not have been able to see the complexity and weakness in the dam’s initial foundation – they said.
I think the general public can find fault here. We can relate to all buildings in B.C. that come under foundation inspections, as we inherently know that the security of any major building is reliant on being built on a sound foundation.
Let’s demystify this engineering jargon here and say whoever was responsible for the design of the dam’s foundation and the core samples that were taken at the time to determine if a dam could be safely constructed on that site, with a glacial till environment, failed to understand the risks involved here.
Does this leave the government off the hook here? I think not.
Geoff Clayton
Maple Ridge