MEC&F Expert Engineers : NTSB issues preliminary report on BNSF oil train crash at Doon Iowa that spilled 230,000 gallons of crude oil into floodwaters in the northwestern corner of Iowa

Monday, August 13, 2018

NTSB issues preliminary report on BNSF oil train crash at Doon Iowa that spilled 230,000 gallons of crude oil into floodwaters in the northwestern corner of Iowa


NTSB issues preliminary report on BNSF oil train crash at Doon Iowa
(Source: National Transportation Safety Board press release, August 9, 2018)

WASHINGTON, D.C. — 


On June 22, 2018, about 4:35 a.m. central daylight time, southbound BNSF Railway (BNSF) freight train U‐CPGSAP‐059 derailed 33 jacketed DOT‐117R tank cars at milepost 165.3 on the BNSF Marshall Subdivision in Doon, Lyon County, Iowa. The train was being operated in a distributed power configuration with 2 head-end locomotives, 2 head-end buffer cars, 98 tank cars, 1 rear-end buffer car, and 1 trailing distributed power unit (DPU) locomotive loaded with about 2,426,325 gallons of UN1267 petroleum crude oil. Maximum authorized speed on the territory was 49 mph. The Federal Railroad Administration (FRA) determined the train speed was about 48 mph when the train encountered the emergency brake application. A total of 10 tank cars were breached, releasing about 230,000 gallons of crude oil. The area received 5 to 7 inches of rain during the 48 hours prior to the accident, washing out track and flooding a tributary of the Little Rock River and farm fields adjacent to the derailment location. (See figure 1.) Released crude oil reached the Little Rock River and prompted the evacuation of 18 to 20 people. No injuries were reported. A unified command consisting of BNSF, U.S. Environmental Protection Agency, Iowa Department of Natural Resources, and Lyon County, Iowa, was established to mitigate and recover the released crude oil.

ConocoPhillips Canada Marketing & Trading ULC originated the shipment from the Hardesty Terminal at Rosyth, Alberta, Canada, and its destination was the ConocoPhillips Company in Houston, Texas. The hazardous material released in this accident was identified as Surmont Mix A, a heavy crude oil and diluent mixture that exhibited an American Petroleum Institute (API) gravity of 19.9, initial boiling point of 115.0 degrees, flash point of -31 degrees, and vapor pressure of 4.7 psi. While these characteristics would have placed the material in Packing Group II (flash point less than 73 degrees and initial boiling point greater than 95 degrees), the shipper classified the material as Hazard Class 3, Packing Group I (highest degree of danger).

On July 10, 2018, National Transportation Safety Board (NTSB) investigators completed on-scene work in Doon, Iowa, where tank car wreckage was staged after the accident. Additional investigative work to examine parts removed from one of the tank cars is planned at the NTSB laboratories in Washington D.C.

The derailed tank cars were originally specification DOT-111A100W1 that were built to the Association of American Railroads CPC-1232 industry standard for tank cars ordered after October 1, 2011, for use in crude oil and ethanol service. Each tank car had about 29,000 gallons capacity and was equipped with a jacket, insulation, and full-height headshields. From 2016 through 2017, the tank cars were retrofitted to specification DOT-117R in accordance with Pipeline and Hazardous Materials Safety Administration (PHMSA) regulations, by replacing the bottom outlet valve operating handle with a disengaging mechanism designed to prevent unintended opening in accidents.[1] Preliminary findings from the examination revealed breaching damage in 10, or about one-third, of the derailed tank cars. (See table 1. in the report)

Parties to the investigation include FRA, PHMSA, BNSF, The Greenbrier Companies, and Trinity Tank Car.







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DOON, Iowa – 

An estimated 230,000 gallons (870,619 liters) of crude oil spilled into floodwaters in the northwestern corner of Iowa following a train derailment, a railroad official said Saturday.
BNSF spokesman Andy Williams said 14 of 32 oil tanker cars just south of Doon in Lyon County leaked oil into surrounding floodwaters from the swollen Little Rock River. Williams had earlier said 33 oil cars had derailed.

Nearly half the spill – an estimated 100,000 gallons (378,530 liters) – had been contained with booms near the derailment site and an additional boom placed approximately 5 miles (8.05 kilometers) downstream, Williams said. Skimmers and vacuum trucks were being used to remove the oil. Crews will then use equipment to separate the oil from the water.
“In addition to focusing on the environmental recovery, ongoing monitoring is occurring for any potential conditions that could impact workers and the community and so far have found no levels of concern,” Williams said.

Officials still hadn’t determined the cause of Friday morning’s derailment, but a disaster proclamation issued by Gov. Kim Reynolds for Lyon and three other counties placed the blame on rain-fueled flooding. Reynolds visited the derailment site Saturday afternoon as part of a tour of areas hit by recent flooding.

Some officials have speculated that floodwaters eroded soil beneath the train track. The nearby Little Rock River rose rapidly after heavy rain Wednesday and Thursday.

A major part of the cleanup work includes building a temporary road parallel to the tracks to allow in cranes that can remove the derailed and partially-submerged oil cars. Williams said officials hoped to reach the cars Saturday.



Officials still hadn’t determined the cause of Friday morning’s derailment, but a disaster proclamation issued by Gov. Kim Reynolds for Lyon and three other counties placed the blame on rain-fueled flooding. Reynolds visited the derailment site Saturday afternoon as part of a tour of areas hit by recent flooding.

Some officials have speculated that floodwaters eroded soil beneath the train track. The nearby Little Rock River rose rapidly after heavy rain Wednesday and Thursday.

A major part of the cleanup work includes building a temporary road parallel to the tracks to allow in cranes that can remove the derailed and partially-submerged oil cars. Williams said officials hoped to reach the cars Saturday.



The train was carrying tar sands oil from Alberta, Canada, to Stroud, Oklahoma, for ConocoPhillips. ConocoPhillips spokesman Daren Beaudo said each tanker can hold more than 25,000 gallons (20,817 imperial gallons) of oil.

Beaudo said Saturday that the derailed oil cars were a model known as DOT117Rs, indicating they were newer or had been retrofitted to be safer and help prevent leaks in the event of an accident.

The derailment also caused concern downstream, including as far south as Omaha, Nebraska, about 150 miles (240 kilometers) from the derailment site. The spill reached the Rock River, which joins the Big Sioux River before merging into the Missouri River at Sioux City.

Omaha’s public water utility – Metropolitan Utilities District – said it was monitoring pumps it uses to pull drinking water from the Missouri River.

Rock Valley, Iowa, just southwest of the derailment, shut off its water wells within hours of the accident. It plans to drain and clean its wells and use a rural water system until testing shows its water is safe.