The Transportation Safety Board has found that the use of old technology and a lack of training and supervision were responsible for a CN derailment that spilled 40,000 litres of caustic soda into the Cheakamus River.

Despite improvements by the railway, the board said it is concerned about the risk of a similar derailment in the future.

Freight cars in the Cheakamus River valley after the derailment two years ago.
(CBC)

The spill two years ago killed more than 500,000 fish and caused extensive environmental damage on the southwestern B.C. river.

The board released its findings Wednesday in Squamish, B.C.

It said in its report that the three-kilometre train had seven engines, including two in the middle. But those two middle engines shut down less than 15 minutes after leaving North Vancouver because they were incorrectly set up to pull in the wrong direction.

Alarm bells did go off, but they did not notify the crew that the two locomotives in the middle of the train had shut down.

In turn, the crew did not pass the information on to a new crew that took over in Squamish because the train appeared to be working fine.

The train eventually started stalling on the steep grade and sharp curves nearing the bridge over the Cheakamus River, the report said

When another locomotive at the front of the train was powered up to prevent a stall, the light, empty cars behind 'stringlined,' pulling them over the inside rail of the curve, resulting in a derailment, the report said.

The safety board also found that CN Rail resumed operations of long trains in extreme mountain environments without a proper risk assessment and consideration of the value of local knowledge and experience.

"The Squamish Subdivision is one of the most challenging railway lines in Canada," said Wendy Tadros, head of the Transportation Safety Board, in a written statement.

"It is not like operating between Edmonton and Winnipeg, or even between Vancouver and Jasper. This is an extreme mountain environment with curves that are twice as sharp and grades more than twice as steep as on other CN main lines. There is no room for error."

A CN spokesman said the company is still reviewing the report. At the time of the accident, CN already had policies and procedures in place that, when properly followed and applied, prevent accidents like the derailment near Squamish, said spokesman Jim Feeney.

But because of current and potential legal action against CN, there will be no further comment from the company, he added. 

The Transportation Safety Board is a government organization responsible for investigating transportation accidents. It does not find fault or recommend charges.