Original Mount Polley engineering firm distances itself from tailings pond, says it issued company and province warning
The original “engineer of record” for the Mount Polley tailings pond says it warned the company and the province in 2011 that there could be problems.
Knight Piesold was the engineer firm that designed the facility for Mount Polley and worked for them until February 2011, when AMEC Earth and Environmental took over the job.
On Monday, the tailings pond at the mine near Likely breached sending 10 billion litres of water and 4.5 million cubic metres sediment into nearby waterways.
Knight Piésold Ltd. says it wrote to Mount Polley and to the province’s Chief Inspector of Mines in 2010 and in that letter stated: “The embankments and the overall tailings impoundment are getting large and it is extremely important that they be monitored, constructed and operated properly to prevent problems in the future.”
In a statement issued to the media Friday, Knight Piesold said it cannot comment on, “the details of the incident, or on the design, construction, operations, water management practices or any other aspects of the Mount Polley tailings storage facility,” after February of 2010.
The company did say that during the time Knight Piesold was the engineer or record for Mount Polley, the tailings pond operated safely and as it was designed, but pointed out that the original engineering was for a lower water volume that the facility reported held when it collapsed.
“Significant engineering and design changes were made subsequent to our involvement, such that the tailings storage facility can no longer be considered a Knight Piésold Ltd. design,” it states.
According to Knight Piesold, AMEC Earth and Environmental conducted a review for Knight Piesold and concluded that “the three embankments were well-designed and well-constructed entities from a dam safety perspective.”