Thursday, July 14, 2011

Here Comes a Freeway of Air Polluting Trains

I am a numbers and graphs kind of guy. I have spent too much time looking at research and scientific reports to shed this tendency. I literally get excited when I see a graph that simply and elegantly tells a story. One of my recent favorites appears below.

This graph is important in the human health discussions relating to the Cherry Point coal terminal. The story it tells is that when it comes to diesel particulates, that trains are better than tractor-trailer semis but only slightly better. And while project proponents will talk about EPA’s Tier IV standards, wood stove smoke, the greater fuel efficiency of trains, and reductions in greenhouse gases, they cannot escape the fact that when trains do work they emit diesel particulates at a level similar to semis moving the same amount of cargo.

As the debate about this project has always been centered on issues of cargo and scale, it is important to translate figures like these and impacts so that they are accessible to folks who might not understand the implication of Tier IV standards or the relative health implications of wood smoke versus diesel particulates. For me this hit home when we used the above numbers and applied them to the current situation.

Just to help us understand the issue and scale a little bit better, we asked ourselves a question. The question was this: If we look solely at the diesel particulate emissions associated with the hauling of 48 million metric tons of coal through communities all along the 624 mile route in Washington State, how many diesel semis would it take to create that same level of DPM emissions. We felt it would be instructive to know whether we were talking about a small number or a large number. Would this number make us feel better about this proposition or cause us even more concern?

So we calculated stack emissions for full trains coming in and empty but still weighty trains exiting on their way back to the mines. From that exercise we derived two numbers: one that examined high capacity coal cars and one that used standard coal cars. Once we derived that number we went through the same exercise with semis—full and empty—and got an emissions number for those vehicles. Each analysis used the grams per ton-mile described in BNSF’s slide above.

The result of these multi-step analyses astounded us. When put in terms of semis the level of diesel particulate emissions from these coal trains (we did not calculate for existing traffic or the 6 million metric tons of additional cargoes) came out to 2.6 million semis per year for heavier cars (1.3 million full and 1.3 million leaving empty) and 2.8 million semis per year for the lower capacity coal cars. So this translates the question before us now on Cherry Point into: Are communities in Washington willing to welcome a new freeway’s worth air pollution—one semi’s worth of diesel particulates every 11 or 12 seconds—into the heart of their communities?

Are You Ready for a Convoy?