The proposed Keystone XL pipeline is back in the news, with supporters touting its benefits for economic growth and with opponents changing their focus from its impact on global warming to the more immediate potential risks stemming from pipeline leaks.  As I have written before (see Keystone Controversy), I am opposed to its construction.

Let’s start with a bit of background.  The proposed Keystone XL pipeline would transport petroleum from the Canadian Oil Sands to refineries in Oklahoma and Texas.  The Canadian Oil Sands consist of heavy oils mixed with sand and a lot of other impurities in a viscous, gelatinous state.  At present they are recovered by excavation using the largest earth moving equipment ever built by humans, leaving behind a scarred, barren, and contaminated landscape. (See Keystone Controversy for a picture)  Only 20% of the oil in the deposits can be recovered via excavation.  The remainder is too deeply buried, so the plan is to inject steam into the ground to melt the oil and to then pump it out.  The petroleum from the oil sands is too thick to flow long distances in pipes even when heated.  Therefore, in order to be able to transport it by pipeline, it must first be diluted with lighter hydrocarbons, generally components of gasoline.  The resulting liquid is referred to as diluted bitumen, or in oil industry parlance, “dilbit”.

Below is a map of the proposed route of the Keystone XL Pipeline.  Please note on the map the location of the existing Keystone Pipeline – the reason the proposed new one has the XL tagged on to its – and the Ogallala Aquifer.

admin-ajaxAs I have touched on in several earlier columns the only hope that we have of limiting the increase in carbon dioxide in the atmosphere to 450 ppm or less, the concentration above which changes in our climate will have dramatically negative impacts on human civilization, is to leave well over half of all currently known fossil fuel reserves in the ground, forever.  Building the Keystone XL pipeline and proceeding with the extraction of the Canadian Oil Sands will result in us blowing right by the 450 ppm limit.  This is the primary reason to oppose the Keystone XL pipeline.  Unfortunately, humans are not generally predisposed to making immediate sacrifices to stave off long-term risks, so the climate change-based opposition to the Keystone XL pipeline has not been successful, at least not yet.

I reviewed the Ogallala Aquifer in “Water Part IV: When the Well Goes Dry”.  It is a massive underground water deposit which has been underneath the middle of the U.S. for millions of years.  At present it is being utilized for both drinking water and agricultural purposes at rates many, many times faster than its very slow replenishment rate from rain water seeping down to it from the surface.   Without the water from the Ogallala Aquifer, agricultural production in the U.S. would drop in a catastrophic fashion and thousands of western cities and towns would have no drinking water source.  So contamination of the Ogallala Aquifer with dilbit would be a disaster of epic proportions, and it is this risk on which the opponents of the pipeline are currently focusing.  This, I believe, is a mistake.

As you can see from the map below, the U.S. already has 2.5 million miles of pipeline for petroleum products and natural gas.  They bring crude petroleum to refineries and transport natural gas, gasoline, and diesel fuel to the rest of the country.  Generally speaking, these pipelines are 1 to 4 feet in diameter and are buried 3 to 6 feet underground.  From working in the chemical industry, I am quite familiar with the U.S. pipeline network, but my impression from the reports I read and hear is that neither the general public nor the news media seem to be aware of its existence.

The U.S. pipeline network is an essential element of our national economy.  If the pipeline network did not exist, the liquids it carries would have to be transported by truck and ship, which would require orders of magnitude more energy consumption and the construction of an armada of new trucks and ships.  Barring a drastic reduction in the use of fossil fuels in the U.S., switching from pipelines to trucks and ships is not feasible; they would never be able to keep up with demand.

While a pipeline rupture can cause a lot of damage, overall pipelines are a safer mode of transport for hazardous materials compared to trucks and ships because ruptures are far less frequent than oil tanker or tanker truck accidents.  An appropriate analogy is that pipelines are like air travel for people and oil tankers and tanker trucks are like cars.   Air travel involves far fewer accidents overall, but a plane crash is much more severe than a car accident.

So if pipeline accidents can be bad, why I am criticizing the opponents of the Keystone XL pipeline for focusing on their potential to contaminate the Ogallala Aquifer?  When you look at the maps above you can see that much of our current pipeline network, including the current Keystone Pipeline, is already on top of the Ogallala Aquifer.  Therefore, any additional contamination risk to the Ogallala Aquifer stemming from the Keystone XL pipeline would be mathematically negligible.

Furthermore, contamination of the Ogallala by pipeline leaks is not very likely.  A distinctive feature of the Ogallala is that it is so isolated from the surface it is difficult for even rain water, a free-flowing, low-viscosity liquid, to reach it from the surface. If rain water has difficulty reaching the Ogallala, then large hydrocarbon molecules leaking from a pipeline do not pose a particularly troubling contamination risk.  To a large degree, the statement in the previous sentence has already been field tested.  Much of the pipeline network above the Ogallala has been there for 50 years, during which time there have been many leaks, both large and small, and they have not contaminated the water below.

I understand and sympathize with the frustration that opponents to the extraction of the Canadian Oil Sands feel from the lack of success in stopping the project based on global warming arguments, but I would encourage them to stay with it.  Shifting the focus to pipeline leaks provides the other side with a much better chance of winning the public debate.  Mother Nature is stating her opinion on global warming with more authority of late.  The public will come around.

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