Independent investigators into the Mount Polley tailings pond breach have determined that the breach was due to poor engineering and design.
A report released today states that the dam was unknowingly built on top of glaciolacustrine (sub glacial) clay that is prone to shearing under weight. The slope of the dam was also too steep, although the mine was taking steps to fix that at the time of the collapse.
The investigators likened the initial construction of the dam on the soft geology to “loading of the gun” and the steep slope designs “pulling the trigger”. They ruled out human intervention, lack of inspection and piping or internal erosion as factors.
Investigators stated that regulatory changes around tailing ponds in BC are needed and that they “firmly reject any notion that business as usual can continue.”
“I’m relieved about the fact that there is a cause and now that it is identified we can move forward and take all the steps that are necessary to remove the risk as much as you can” said Mines Minister Bill Bennet
In response to the report, Bennet announced that all mines in BC with tailings ponds will be required to report and fix any risks due to geology similar to Mount Polley. Independent review boards of tailings damns will also be set up by each BC mine.
The government will also start a core review with the aim of instating seven all recommendations the panel made.
As for when exactly the Mount Polley mine will re open, Bennet acknowledged the importance of the mine to the local economy, but said they will be taking their time,
“We are going to take the time that is necessary to review the application we have from the company and certainly the use of the existing tailings storage facility is not something that is planned for anytime soon.”
Two more separate inquests on the disaster are still in progress.
The full independent report can be found here.
Something going on in the Prince George area you think people should know about?
Send us a news tip by emailing [email protected].
