BANFF, Alta. — The Transportation Safety Board has determined that a fractured piece of railway track caused a derailment last year that sent coal ash waste into a creek in Banff National Park.
A report released Thursday found that a loose joint and minor cracks in the track had worsened over time with train traffic.
"Although performed in compliance with regulatory and railway requirements, the regular monthly, detailed, and visual track inspections did not specifically identify the deteriorating condition of the heel block assembly,'' said the report.
"Environmental monitoring will continue for three to five years."
After the Boxing Day accident, Transport Canada asked the railway industry to come up with specific rules for inspections and repairs. The agency also recommended rail crews should better discuss the risks of hazardous loads they might be carrying.
Fifteen cars on the Canadian Pacific Railway train went off the tracks and destroyed a bridge near the resort town. A coal combustion by-product called fly ash, as well as soybeans, spilled into 40 Mile Creek.
The ash, which came from the Boundary Dam power plant near Estevan, Sask., is used to make concrete.
It has hazardous characteristics that include the ability to smother sediment organisms. It's also toxic when inhaled, but is not classified as dangerous under the Dangerous Goods Act.
The report said no one was injured in the derailment, but one crew member sought medical attention after inhaling the ash. The train's conductor was not aware of the risks of the substance, it said.
Most of the spilled soybeans were removed by vacuum, the report added. Crews worked to clean up the ash in the spring until the creek's flow increased.
"It is anticipated that environmental monitoring will continue for three to five years and additional remediation may be necessary,'' the report said.
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