Rail transportation safety investigation R20W0025

The occurrence

Please note that the following information is preliminary and subject to change as the TSB continues its investigation.

On 6 February 2020, a Canadian Pacific Railway (CP) crude oil unit train was proceeding eastward at about 42 mph on the CP Sutherland Subdivision. The train originated at Rosyth, Alberta, and was destined for Stroud, Oklahoma, USA. At 0615 Central Standard Time, the train experienced a train-initiated emergency brake application at Mile 43.4, about 1 1/2 miles west of Guernsey, Saskatchewan. Subsequent examination identified that 32 tank cars (Lines 32 – 63 inclusive) had derailed. Several tank cars were breached and an undetermined amount of petroleum crude oil product was released. The product ignited and a pool fire ensued involving a number of tank cars. There were no injuries reported. As a precaution, the Reeve of the town of Guernsey required the evacuation of about 85 people. The temperature at the time of the accident was about −18°C.

What we know

The train crew was composed of a locomotive engineer and a conductor. The train consisted of 2 distributed-power locomotives (1 on the head-end and 1 on the tail-end), a covered hopper car loaded with sand located in position 2, followed by 104 tank cars loaded with petroleum crude oil (UN1267, Class 3 PG I) and another covered hopper loaded with sand located the 107th position (108 rolling stock in total). The train weighed 14896 tons and was 6445 feet long. 

The derailed tank cars were all DOT 117J100-W tank cars. The tank cars located from line 32 to 63 (32 cars) derailed. One derailed tank car that remained upright was otherwise unaffected and was subsequently re-railed. Of the remaining 31 derailed cars, about 19 derailed cars were involved in a pool fire from released product west of the crossing, while an estimated 12 cars derailed east of the crossing but were not directly involved in the fire.

To date, there have been no mechanical defects observed that could be considered causal. A review of the locomotive event recorder download determined that the train was handled in accordance with regulatory and company requirements.

The type of petroleum crude oil involved in this occurrence had properties consistent with petroleum crude oil that the TSB has evaluated in previous investigations involving crude oil.^{Footnote 1}

Work done to date and ongoing

The investigation is currently in the field phase. Three TSB investigators are working alongside investigators from the US National Transportation Safety Board (NTSB) and the tank car manufacturer (Trinity) to gather information from the occurrence site.

Each tank car must be cleaned, purged, and staged prior to inspection. As of 12 February 2020, about 17 of the derailed cars have been examined, with several cars exhibiting breaches.

A record of any product recovered during site remediation will be maintained in order to more accurately determine how much product was released to ground or atmosphere. The product appeared to be primarily contained in a large ditch between the rail line and Highway 16 to the north of the rail line. It does not appear that any waterways were affected. A more precise estimate of the amount of product lost will be available once the site work is complete.

Next steps

There is significant industry interest in documenting the performance of the DOT 117J100-W tank cars (containment integrity and fire resistance).  Detailed site examination of all of the derailed tank cars will continue, in challenging conditions, until completed.

Once site work is complete, all available information will be reviewed in order to make a more accurate assessment of the tank car damage sustained and the amount of product released. This work, will take some time.

Any tank car and track components of interest that are recovered from the site will be sent to the TSB Engineering Laboratory in Ottawa for detailed analysis.

Safety communications

Media materials

Deployment notice