Union Pacific’s failure to maintain its track and equipment resulted in broken and sheared lag bolts, which caused the June 3 derailment of a train near Mosier, Ore., according to a preliminary report from the Federal Railroad Administration.
The Federal Railroad Administration has issued a preliminary factual findings report on the June 3 derailment of a Union Pacific Corp. train carrying crude oil near Mosier, Ore. in which it found the railroad to be at fault in the incident.
Union Pacific’s failure to maintain its track and equipment resulted in broken and sheared lag bolts, which led to tie plates loosening from ties, according to the FRA report. The loosened tie plates allowed the rails to be pushed outwards as trains moved across them, causing the gauge to widen, which in turn, caused the derailment.
Sixteen of the trains 94 tank cars, all of which were loaded with crude oil from the Bakken formation, went off the tracks en route from New Town, N.D. to Tacoma, Wash., puncturing one car and spilling its contents. The leaking crude oil came into contact with an ignition source, which sparked the fire that eventually spread to four other cars and burned for 14 hours.
UP filed a report with the FRA shortly thereafter citing one or more broken bolts as the cause of the incident, which damaged area infrastructure and caused the evacuation of about 100 local residents.
“Unless or until additional details come to light, FRA has made the preliminary determination that Union Pacific’s failure to maintain its track and track equipment resulted in the derailment,” the administration said in the report. “Broken and sheared lag bolts, while difficult to detect by high-rail, are more detectable by walking inspection combined with indications of movement in the rail or track structure and/or uneven rail wear, and are critically important to resolve quickly.”
FRA noted in its report that the train’s modified DOT-111 tanks cars, referred to as “jacketed 1232s,” were loaded by Dakota Plains on behalf of U.S. Oil & Refining Company and “performed as expected in the incident based on tank car performance metrics.” The jacketed 1232s were equipped with full-height head shields and metal jackets with insulation, but the cars did not have thermal protection.
In addition, the FRA report said that although the train was equipped with an air brake system and was operating on distributive power, electronically controlled pneumatic (ECP) brakes might have lessened the damage caused by the derailment. Distributive power provides power to the train from both ends of and provides improved braking over conventional air brakes, while ECP brakes use an electronic trainline signal to activate brakes on all cars throughout a train simultaneously.
FRA’s Office of Research and Development conducted simulations in which it found that ECP brakes would have provided additional train control, potentially shortening the stopping distance, and leading to a less severe derailment. As a result, two fewer tank cars may have derailed, and one less tank car may have been punctured, according to the FRA.
“Electronically controlled pneumatic (ECP) braking technology has yet to meet service reliability standards in industry tests, including by Union Pacific,” the railroad said in a statement. “The train involved in the Mosier accident was equipped with distributed power, which has a braking capacity very similar to ECP.
“It is speculative to suggest that ECP brakes would have prevented cars from derailing or prevented a tank car puncture, and we plan to reach out to the FRA to understand the modeling system used to come to its conclusion.”
Since the derailment, the FRA has conducted walking inspections of all curved tack areas in the Columbia River Gorge and the BNSF track on the Washington side of the Columbia River, ordered a metallurgy test on the broken bolts, and ran a geometry car with a Gage Restraint Measurement System on UP track in its Portland, Ayer, and Spokane subdivisions in an attempt to ensure safety along the route.
For Union Pacific’s part, the railroad said it is increasing the frequency of inspections and conducting walking inspections of curves containing lag bolts.
“As part of our ongoing track renewal program, lag bolts with this fastener system are being replaced with rail spikes, which provide higher levels of defect detectability in standard inspection processes,” UP added.
FRA said it is “evaluating potential enforcement actions, including violations, and other actions to ensure Union Pacific’s compliance with applicable safety regulations.”
FRA: UP at fault in Oregon crude oil train derailment
