Fact Sheet: Bakken Shale Oil

On this site we talk a lot about Bakken shale oil from North Dakota, and we sometimes refer to trains carrying it as “bomb trains”, because they explode so often. Here’s a deeper explanation of where this kind of oil comes from and its particular dangers. When we talk about the dangers of crude-by-rail, this is mainly what we’re talking about, although we’re also concerned about tar sands.

What is the Bakken Formation / Bakken shale?

bakken formation

The “Bakken formation” is a layer of rock, deep under the ground, under a large area of North America. The most important part of it is in North Dakota, but some of it is in Montana and Canada.

This rock – a type of shale – was formed over 300 million years ago, before even the dinosaurs walked the Earth. Over millions of years, minerals and bits of organic matter collected at the bottom of what was then an ocean. Over time, this become compressed into rock (this kind of rock is called sedimentary).

Where’s the oil?

Those little bits of organic matter decomposed and were transformed under pressure into oil. Unlike other locations where large pools of oil can be tapped easily, this oil is tightly bound to the rock. To extract this oil, drillers must break up the rock in a process called fracking.

Why is Bakken shale oil especially dangerous?

Bakken volatilityThe oil is much lighter, more flammable, and more volatile than other crude oils. It’s similar to gasoline, and doesn’t look like the gunky black oil that we commonly think of.

This graph shows that Bakken shale oil vaporizes much more quickly than other crude oils. In fact, the oil has a “flash point” as low as 73°F. That means that the oil can spontaneously ignite at the temperature of a pleasant summer day – which can occur any time of the year in the Bay Area.

Sometimes the oil producers add acids to the chemicals used in fracking to further dissolve the rock and obtain more oil. There is some suspicion that these acids may remain in the fracked oil and slowly corrode the railcars that are used to transport it. This may help explain why there have been so many exploding trains in the last year.

The Lac-Mégantic tragedy and other derailments


On July 6th, 2013, a train carrying Bakken shale oil derailed in the small town of Lac-Mégantic in Québec, Canada. Many of the railcars exploded, and the oil flowed through the sewers, lighting many buildings on fire. It flowed onto their nearby lake – the lake itself was on fire. The downtown was destroyed and 47 people were killed.

Several times during the night, a railcar exploded like this, producing a huge fireball and boom.

Since then, several other trains carrying this explosive Bakken shale oil have spilled oil that has caught on fire. Luckily, none of the other incidents killed anyone, but some have been very close to towns, and have resulted in evacuations.

The other incidents of Bakken shale oil train explosions have been: Nov. 7th, 2013 in Aliceville, AL, Dec. 30th, 2013 in Casselton, ND, and Jan. 7th, 2014 in New Brunswick, Canada. Later in January there was a train derailment on a bridge over the Schuylkill River near Philadelphia; that train was carrying crude oil, which was almost certainly Bakken shale oil.

Public health impacts

Whenever oil is transferred (say, from a train to a storage tank), small amounts of vapor are released. These are called “fugitive emissions”. These vapors are in the form of VOCs – volatile organic compounds – which can aggravate asthma and respiratory problems as well as increase the risk of cancer. Because Bakken shale oil is so volatile, we can expect that it will release more VOCs than other types of crude oil.

Climate change impacts

Natural gas flaring at North Dakota wells is very visible on nighttime satellite photos.

Natural gas flaring at North Dakota wells is very visible from space.

Because Bakken shale oil is a “light” crude oil, it takes less energy to refine into useful products like gasoline. That’s a good thing. However, there are two factors that increase its climate change impacts. First, some of the gases that come with it are flared off – so much so that it can be seen from space. The amount of gases that are wasted this way could power Pittsburg. Second, fracking wells leak gases into groundwater and into the air. One of the gases, methane, is very powerful at trapping heat over the short-term (20 years or so). So it is likely that extracting Bakken shale oil is actually very bad for our global climate.

How are ordinary people responding?

All over the US and Canada, people are organizing grassroots groups to stop these bomb trains. Some of the groups opposing crude-by-rail and shipment of Bakken shale oil are nearby, in Benicia, Martinez, and Davis. In Washington state there’s 350 Seattle and several groups collaborating in Spokane. We know about PAUSE – People of Albany United for Safe Energy (Facebook page) and Lac-Mégantic has a citizens’ committee in wake of the disaster there. We know there are more out there – let us know about them!

How are governments responding?

Under pressure from these various groups, governments are stepping up – gradually. City Councils in several towns (including Seattle and Spokane, WA) have called for moratoriums on crude-by-rail, in large part because of the dangers of these “bomb trains” of Bakken shale oil. This provides pressure on the Washington state government to regulate this threat.

There are a number of statements from federal agencies; unfortunately, these are suggestions, not rules. The Department of Transportation issued a nice-sounding statement with little backing it up about the problem of shippers labeling the oil as less explosive than it really is. The National Transportation Safety Board made recommendations that these trains stay away from towns, that the railcars be improved, and that the shippers be audited to make sure they properly classify the oil and have plans in case of spills. Again, unfortunately, none of these suggestions are realistic.

In one very promising development, the County of Albany, NY, has issued a moratorium on crude-by-rail projects there and has asked their county Health Department to thoroughly investigate health and safety effects of crude-by-rail before it will allow any projects to move forward.

What about local government responses?

Pittsburg has decided that portions of the EIR for the WesPac project need to be re-opened for public comment (it is now up to WesPac to decide whether to go forward). Benicia has postponed the EIR for Valero’s crude-by-rail project there. The Democratic Party Central Committee of Contra Costa County has passed a resolution against the WesPac project and against it being relocated to anywhere else in Contra Costa. Berkeley and Richmond City Councils have passed resolutions against crude-by-rail.

Is this stuff already coming to the Bay Area?

Unfortunately, yes. While we have had great success fighting the proposed WesPac oil terminal, we have just recently learned that Kinder Morgan is receiving trains of crude oil, and that the Bay Area refineries are receiving shipments of Bakken shale oil from there and from a facility in Sacramento. We want to work with other communities in the Bay Area and along train routes to stop these trains.