Repost from The Conversation US, Boston
[Editor: On this page I present TWO articles by Bryan W Schlake, Instructor in Rail Transportation Engineering at Penn State Altoona and a former employee of Norfolk Southern Railway. The first, directly below, explores crude-by-rail risks and seems overly sympathetic to the rail industry. The second more interesting and informative article, farther below (click here) explores ways to improve crude-by-rail safety. – RS]
Despite disasters, oil-by-rail transport is getting saferBy Bryan W Schlake, April 14 2015, 5.48am EDT
For many Americans, railroad transportation rarely appears on our mental radar, and when it does, it often comes with a negative context: either we are stopped at a railroad crossing while running late for work or we come across a news article with shocking images of smoke and flames accompanied by reports of exploding tank cars.
Months go by with no thought of railroad transportation, until another derailment occurs, and we again associate trains with fire and danger.
With US crude oil production nearing all-time highs – averaging over 8.5 million barrels per day in 2014 – many are expressing fears about the potential of a crude oil spill in their community. And last week, the National Transportation Safety Board released “urgent” recommendations to promote the safety of shipping crude oil, ethanol and other flammable materials by rail.
What’s behind this rapid rise in oil-by-rail transport? How dangerous is it and can new technology make it safer? To answer these questions, we’ve prepared two articles on transporting oil by rail in the US. The first explores the economic drivers and assesses the rail industry’s record on safety; the second evaluates the technology, research and railroad operating practices that can lead to the greatest level of public good.
By better understanding the underlying issues, we can have a meaningful dialogue and take action towards the common goals of improved safety, security and economic stability.
Economics of oil by rail
Oil production in the US is booming. Last year, for the first time since 1987, annual US field production of crude oil topped three billion barrels, a 170% increase since 2008.
Technological advances such as hydraulic fracturing, or “fracking,” and horizontal drilling allowed for increased production, notably in the Bakken formation in North Dakota. But rail has been integral to the domestic oil surge. It was the availability of low-priced, flexible transportation that allowed crude oil to be shipped to US coastal refineries, creating the market for Bakken oil.
As pipelines quickly reached capacity, oil shippers turned to the railroads, which provided multiple incentives, including: flexibility in shipping options and contract timelines, shorter transit times to the refineries (five to seven days by rail compared with 40 days by pipeline), and the ability to choose which refineries to use. While pipelines allow for higher volumes to be transported, the higher speed afforded by rail results in reduced transit time for long distances.
As a result, Bakken oil production increased from 81,000 barrels per day in 2003 to more than one million barrels by mid-2014, with more than three-quarters of those barrels moving daily out of North Dakota by rail. While carloads of crude oil increased dramatically, on the whole it still comprises a relatively small portion of total railroad shipments – only about 1.6% of all carloads for US Class I railroads.
Because of increased domestic production and increased imports from Canada, 66% of US oil demand is now sourced from North America, a shift that’s lowered imports and will create billions of dollars in economic activity over the next several decades.
Assessing the risk
While there exists no universally accepted definition of risk, it is widely accepted that the risk associated with transportation of hazardous materials must factor in both the probability of a release of the hazardous material as well as the magnitude of the consequences of that release.
Statistically, the probability of an oil train derailment is very low and lower than other forms of transportation (see figure, below). But the potential undesirable consequences are relatively high, including damage to human life, property and the environment.
A worst-case scenario occurred in the Lac-Mégantic accident of 2013 in Canada, which resulted in 47 fatalities, another 2,000 people evacuated from their homes, almost 1.6 million gallons of crude oil released and millions of dollars in property damage.
Since 2013, three other notable oil train derailments have occurred in Canada, including recent derailments in Ontario, and seven in the US, including the recent derailments in West Virginia in February and Illinois in March. Using data available from the FRA Office of Safety Analysis, here is a summary of statistics for US crude oil train derailments from 2013 to 2014:
- eight derailments were reported involving a crude oil release
- two of these derailments resulted in a release exceeding 450,000 gallons
- two of these derailments resulted in a release between 15,000 and 30,000 gallons
- the remaining four derailments resulted in a release of 5,000 gallons or less
- injuries were reported in only two derailments, resulting in four total injuries
- no fatalities were reported in any derailment
- people were evacuated in three of these derailments, with the number of people affected ranging from 16 to about 1,000 people
- track and equipment damage exceeded $1 million for all derailments, with only one derailment resulting in more than $5 million in damages (damage to private property or depreciation of property values not included).
In terms of hazardous materials risk, the consequence to human life was very low in these US incidents, with zero fatalities and only four reported injuries.
Environmental and economic impacts, however, were substantial. Recent reports have noted that the amount of oil spilled in 2013 alone from train derailments, at more than 1.1 million gallons, was greater than the total amount of oil spilled from 1975 to 2012. As demand for crude oil shipments has increased, railroads have shifted to using “unit trains” in which nearly every car carries oil instead of the variety of railcar types found on a manifest train. For unit oil trains, the only cars that are not tank cars are the “buffer cars”, typically located in the front and rear of the train to provide an added level of safety for the train crew in the event of an accident.
The use of unit oil trains has resulted in larger amounts of oil being spilled in a single derailment. For example, the majority of oil released in 2013 resulted from only two derailments, occurring in Aliceville, Alabama, in November of 2013 and Casselton, North Dakota, in December of 2013. The recent accident in West Virginia on February 16 of this year likely resulted in a release of similar magnitude to the 2013 spills. The accident in Galena, Illinois on March 5th of this year resulted in a spill of over 200,000 gallons of crude oil released from seven tank cars.
The other side of the coin for risk assessment is the probability of release, which is extremely low when compared with other transportation modes. In 2013, which was the worst year to-date for oil train derailments, about 28,000 barrels of oil were released from railroad tank cars out of the approximately 300 million barrels of oil delivered by rail.
In other words, less than one hundredth of 1% of the volume of oil transported by rail in 2013 in the US was released into the environment. According to an analysis of US oil spillage, the amount of oil spilled by railroads per billion ton-mile transported declined by approximately 85% throughout the 1990s and 2000s. By comparison, pipelines experienced closer to a 40% decline in oil spilled per billion ton-miles over the same period. While this report does not include the recent increase in unit oil trains, it does provide a valuable comparison across transportation modes.
Due to changes in safety culture and numerous technological advances, railroads have continued to improve safety over the last decade, with accident rates reaching all-time lows in 2014 at only 2.24 train accidents per million train miles. The industry has been clear about its goal to continue to use new technologies and improved operating practices to drive accident rates even lower, asserting that “No accident, big or small, is acceptable.”
PART II …
Repost from The Conversation US, Boston
Shipping oil by rail is booming. Technology can make it saferBy Bryan W Schlake, April 15 2015, 6.18am EDT
The Energy Information Administration recently released a map that reflects a massive change to our economy few people appreciate.
The graphic, shown below, shows the latest data on crude oil-by-rail movements around the country and the surge in oil shipments from North Dakota to the different corners of the country. Last year, trains transported more than one million barrels of oil per day in 2014 – a huge jump from 55,000 barrels per day in 2010.
This increase in oil-by-rail transportation has come with a number of high-profile derailments, including an accident in Illinois just last month, which have caused substantial economic and environmental damage. Can technology improve safety? Yes. In much the way automobiles are becoming increasingly high-tech, various stakeholders in rail transportation are exploring various technologies to improve safety.
Building a better rail car (and maintaining it)
Railroads have already taken some steps to improve equipment with better braking systems and upgrades to the track infrastructure. New practices can improve safety as well, including better track inspections, speed restrictions for oil trains and choosing routes to reduce exposure to population centers. Railroads have also increased the use of freight car defect detectors installed alongside the the tracks that automatically identify mechanical defects on the railcars based on force, temperature, sound, or visual measurements.
Many of these technologies are already being implemented by the railroads both to improve safety and to increase economic benefits. In addition to minimizing the safety risk associated with derailments, improved track and vehicle inspection practices help to reduce the potential for delays, which can cost railroads hundreds of dollars per hour.
An economic analysis from 2011 estimated that the annual train delay costs due to railcar defects (resulting in trains stopping unexpectedly enroute) was over US$15 million for all US Class I railroads. For comparison, each year the four largest US Class I railroads spend an average of $35 million on track and equipment damages due to main-line derailments. Thus, the economic drivers behind the reduction of derailments and train delays are quite substantial.
Federal agencies and lawmakers are also working to ensure that federal safety requirements and public policy address the new transportation landscape resulting from the domestic oil boom and increased imports from Canada. The federal government is currently considering new safety standards for improved tank cars specifically designed for the transportation of crude oil.
However, movement towards such legislation has presented considerable challenges due to the fact that the vast majority of tank cars are owned by private companies other than the railroads that transport them.
As a result, questions arise regarding who should bear the economic burden of replacing and/or retrofitting the crude oil tank car fleet. Due to safety and economic incentives mentioned above, some railroads have already begun to purchase their own improved tank cars, but this has not become a universal trend across the industry.
Role of research
Researchers, too, are exploring how technology can improve safety in a variety of ways, including:
Improved Tank Car Design: The Association of American Railroads (AAR) is working to promote tougher federal standards for tank cars carrying crude oil and other hazardous liquids. Extensive research is ongoing both within the Federal Railroad Administration and at various universities to assess tank car safety and develop an optimized tank car design: Cooperative Research in Tank Car Safety Design.
Track and Infrastructure Inspection: Railroad track failures have been found to be a leading derailment cause in the US. As a result, railroads have begun to perform more track inspections, including the use of advanced track geometry vehicles – which use laser systems to measure the profile of the rail – on routes carrying crude oil trains. Ultrasonic rail inspection methods as well as ground-penetrating radar systems are also being developed to improve the ability of railroads to detect track defects.
Risk Assessment: Railroad transportation risk research associated with hazardous materials is ongoing. Risk assessment has included rail defect inspection, evaluating routing and train speed, track quality and an integrated framework to reduce risk. This framework addresses operating practices, train routing, infrastructure, and car design to identify the financial and safety risk associated with hazardous materials transport by rail.
Automated Condition Monitoring Technologies: Various wayside detector systems have been developed and installed across the country at locations adjacent to track to assess the condition of locomotive and freight car components enroute. These systems incorporate various technologies to identify critical defects resulting in both safety and economic benefits. Some key technologies include:
- infrared temperature sensors used to measure overheated wheels/bearings
- accoustic bearing detectors to identify worn roller bearings in railcars
- laser systems to measure wheel profiles and identify worn wheels
- machine vision systems to detect low air-hoses, structural defects and broken or missing railcar safety appliances
- load impact sensors to identify damaged wheels that are out-of-round or exhibit flat spots.
Advanced Braking Systems: Both technology and operating practices can play a role in improving braking for oil trains. Some have suggested the use of Electronically Controlled Pneumatic (ECP) brakes. ECP brakes allow for faster application of the brakes on all cars in a train using an electric signal, instead of an air signal, to initiate a brake application.
ECP brakes have been used on a limited basis for coal trains, but the costs have not been proven to justify the safety and economic benefits. A better option may be the use of either:
- distributed power, where locomotives are dispersed throughout the train (i.e. front, rear and even in the center) and/or
- two-way end-of-train devices (EOTD) that allow brake signals to be initiated from the rear of the train.
Both of these operating practices result in faster braking and reduce “run-in”, where the cars in the front of the train begin braking before those on the rear, causing the rear cars to “run-into” the cars in front of them, creating higher in-train forces. After these measures were proposed by the US Department of Transportation in July of 2014, US Class I railroads agreed to implement enhanced braking in the form of distributed power or two-way EOTDs on all oil trains.
Positive Train Control (PTC): This technology will automatically slow or stop a train to prevent a collision or derailment due to human error, such as speeding or missing a signal. After a federal mandate in 2008, railroads have begun to develop and install this GPS-based safety overlay system, which will eventually cover more than 60,000 miles of track in the US.
Emergency Response: Railroads are working together with various organizations to improve community safety through emergency response training.
In addition, new technologies are being developed to improve the speed and effectiveness of environmental cleanup efforts. For example, researchers at Penn State University have developed a patented technology called Petro-SAP to absorb oil from the environment after a spill. Technologies like this can be used in the future to mitigate environmental impact of train related oil spills.
While the risk associated with oil train derailments has not been eliminated, the transportation of crude oil by rail has certainly become safer through extensive research, development and implementation of new technologies.
Continued efforts by railroads, government agencies, research institutions and universities will continue to improve the safety of crude oil transportation by rail, reducing risk and potentially alleviating public fears associated with railroad transportation.