Broken rail caused 2019 crude oil train derailment, fire in Sask.: TSB

The Transportation and Safety Board (TSB) says a broken rail caused a Canadian Pacific train derailment in Saskatchewan in 2019 that caused 1.77 million litres of crude oil to leak and about 20 train cars to burn.

The TSB has released its report into the derailment that happened just after midnight CST on Dec. 9, 2019, just east of Guernsey, Sask., a small hamlet of about 100 people located 114 kilometres east of Saskatoon.

The train had 101 cars, 99 of them filled with oil. It was loaded in Hardisty, Alta., and headed for Oklahoma.

The report says the train was heading east when the crew noticed a gap in the rail and initiated the emergency brake.

"Shortly after, crew members observed a large explosion behind them as the head-end locomotive and first car separated from the train. Subsequent inspection determined that 33 cars derailed, of which 20 tank cars had breached, and the released product ignited, resulting in a large pool fire that burned for nearly 24 hours."

Highway 16 was closed. No one was injured and no evacuation was needed.

The investigation found the rail was likely broken under a previous train, "causing an undetermined length of rail to break away and separate from the track and expose the rail ends."

The report says track components "did not provide adequate resistance to the rail forces initiated by the cold weather at the time of the accident, which contributed to the breaking of the rail." It says that despite regular visual inspections and ultrasonic rail flaw detection testing, "the broken rail went undetected before the arrival of the train."

The safety board report noted that rail in the area was manufactured between the 1960s and 1980s.

Rail traffic on the route had been increasing in the years prior. From 2015 to 2019, the traffic increased by 60 per cent and transportation of crude oil increased by more than 66,000 car loads.

The investigation found the train followed the rules at the time, but said the train's speed of 71 km/h "contributed to the number of cars that derailed, breached, and lost their product."

A second fiery derailment happened near Guersney on Feb. 6, 2020, leading to the evacuation of the community and the release of 1.2 million litres of oil. In response, Transport Canada called for the rail industry to revise its rules.

"If company risk assessments do not adequately consider increases in traffic tonnage, the use of heavier rail cars, and the potential for more rapidly degrading track structure, regular track maintenance activities may no longer be sufficient to maintain track to the required standards, increasing the risk of track infrastructure failures that lead to rail accidents."

The rules were changed, and "now contain a number of safety improvements related to the operation of key trains and the inspection and maintenance of track infrastructure."