Sunday, July 7, 2013

Crude Oil Train Wreck

This weekend there was a serious train derailment in a small town in Canada that may have some serious implications for the expanding use of rail shipments of crude oil. One person is known to be dead and an indeterminate number are missing. Large portions of the town center have been destroyed.

The Incident

According to news reports (here and here) an unmanned train of the Montreal, Maine & Atlantic Railway rolled at high-speed into Lac-Megantic, Quebec and derailed in town. Four railcars carrying North Dakota crude oil were damaged, leaked, and caught fire. An explosion was mixed in there somewhere; witness accounts are a little confused since the incident took place about 1:00 am Saturday morning.

The train had been parked outside of town. The reason has not been publicly announced, but it could have been for a crew rest period, crew switchover, or other legitimate reason. In any case the engineer claims that the brakes were set on all five locomotives and a number of the rail cars. If that is true, then there was a failure of those breaking systems or someone; deliberately or accidentally, released the brakes.

Along with the to be expected (and apparently extensive) blast and fire damage at the scene of the derailment, it appears that large quantities of burning crude (or some other flammable liquid; it is not yet clear from news reports what else this particular train was hauling) made their way into the storm sewer system and spread flames (and possibly secondary explosions of sewer gas?) beyond the immediate area of the fire.

The Cause?

It is way too early in the investigative process to presume to know the cause of the train starting to roll towards town. The whole gamut of possibilities (crew incompetence, maintenance failure, accidental release and deliberate release) remains as the potential cause(s) of the initial roll away. Even the cause of the actual derailment in town could have a number of possible causes (including too fast for the curve, inadequately maintained tracks, obstruction on the tracks, or a deliberate derailment).

There were news reports earlier this year of an al Qaeda related plot to cause a passenger train on a similar trans-border rail line to derail, so it is possible that this derailment was the result of a planned attack by al Qaeda or its wannabes. It is also well known that a number of environmental groups have civil disobedience actions planned against the rail transportation of Canadian oil-sands crude to American refineries (no, this was not Canadian crude and there is a far stretch between civil disobedience and criminal attacks) so there is a remote possibility that an eco-nut (the moral/political equivalent of a Jihadist-waco) could have been behind this.

If it was an eco-nut, it would be unlikely that the derailment, fire and explosions in town would have been the desired consequence. The same would certainly not be true of an al Qaeda wannabe.

Explosions

The news reports include conflicting descriptions of when the explosions came in relation to the derailment and fires. Some claim that the explosions preceded the derailment (and thus may have contributed to the derailment). If that was the case, the only ‘naturally’ occurring explosion would have been caused by a static discharge within one of the flammable liquid railcars caused by the sloshing liquid. The companies that I have worked for placed a ‘nitrogen blanket’ in the head space of all bulk flammable-liquid containers to prevent this from happening, but this is not universally done or required. A blast after the derailment but before the fire would have probably required the same ignition source.

An explosive device could have caused explosions at either time, thus possibly contributing to the derailment or causing the initial release of crude that started the fires. That loose crude would have been ignited by the sparks of the railcar scraping across the pavement.

I have mentioned on a number of occasions that using an explosive device on a toxic inhalation hazard (TIH) railcar would be very difficult; those cars are effectively armored so that they can withstand an internal pressure of 300 psi. A flammable liquid railcar is not as effectively protected as they are expected to withstand much lower pressures. It would not take a really professional bomb-maker to prepare a device that would breach a flammable liquid car.

An explosion after the initial fire would be much easier to explain as being due to ‘natural causes’. If one of the crude cars was breached in the accident (and the liquid ignited by metal to pavement sparks) the pool fire could rest beneath an overturned car that was still intact. The direct impact of flames would both weaken the metal and cause an increase in vapor pressure due to boiling volatiles inside the sealed car. That could fairly quickly lead to a BLEVE (Boiling Liquid Expanding Vapor Explosion) that I have discussed here before.

Security Implications

If this was caused by something as simple as kids playing on an empty train (that is a bit of a stretch considering the number of separate break systems that were supposedly set), then railroads are going to have to reexamine their basic security procedures for trains that are allowed to sit on unguarded tracks. This would not be the first incident of this type, but probably the worst in the way of consequences.

If this was a terrorist attack, or whatever persuasion, then the railroads and TSA (and Congress) are certainly going to have to re-look at the requirements that they have put in place for counter-terrorism security. To date, the only chemicals that have been regulated for security are TIH chemicals, explosives and radioactives. Proving a realistic threat against flammable liquids will greatly increase the cost of rail shipping.

Political Implications

As I noted earlier, many environmental organizations have been politically attacking the increased shipping of crude oil by rail as an end-run around the use of pipelines to handle crude from environmentally sensitive oil reserves. They have effectively blocked (at least for a time; maybe longer, the political end of that action has yet to be written) the approval of the trans-border Keystone XL pipeline.

The expanding use of rail shipments of crude has provided the oil industry a way around that political blockage. If the environmentalists can successfully point at this incident as a prime example of the safety issues related to crude-by-rail shipments, it may make it harder to bypass the pipeline restrictions.

At the very least we can expect to see petitions to the Federal Railroad Administration and its Canadian counterpart to increase the safety rules for the transport of crude-by-rail. At worst we could expect this to be a galvanizing incident in expanding the political and civil disobedience actions against crude-by-rail.

This will also almost certainly re-ignite calls for railroads to provide advance notice to local first responders of the identity and quantity of hazardous materials being transported by rail through their areas of responsibility. It will also serve as an additional rallying cry for organizations calling for the government mandating the re-routing of hazardous chemicals around municipal and urban settings.


A lot is going to depend on the results of the accident investigation being undertaken by the Canadian Government. Everyone involved with the shipment of hazardous materials, particularly crude oil, by rail will need to watch this investigation and the political ramifications closely.

No comments:

 
/* Use this with templates/template-twocol.html */