Saturday, March 22, 2014

Air Quality: Coal Trains and Then the Bad News

A bit of catch up on posts. A study by Jaffe and others (atmospolres/Volume5/issue2/APR, 2014.pdf) on trains and coal train emissions measured short term emissions of particulates. One noteworthy finding is that their measurements indicate that coal dust is being released from passing coal trains. The particulates add to the diesel exhaust particulates from the train engines themselves. The study was of very limited scope and concludes with a few suggestions for further investigation.

John Stark covered this issue rather well first with the pro coal terminal reaction and the counter reaction (coal-terminal-backers-challenge-researchers-dust-findings). Claiming no coal dust is coming off the trains with no studies is just spin. Stark also reported on the local Northwest Clean Air Agency (NWCA) study with a monitor located very near the rail lines in Bellingham (air-agency's-monitor-shows-no-emissions-problems). That investigation indicates good overall air quality on all days but 5 from February 2012 to September 2013.

The NWCA reporting and the Jaffe and others study are apples and oranges. NWCA reports a daily average as that is what is used to determine health effects. Jaffe and others did a bit harder short time frame measurement that allowed discerning particulate levels changes while individual trains were passing. Jaffe and others found coal trains have a greater release of particulates, but the NWCA study suggests, at least at this one spot, the overall air quality impacts are not bad at current train traffic levels despite whatever impacts the coal dust release might have. The NWCA reports that the daily average air quality at the location monitored was good on all but 5 days. The few not so good days were related to air stagnation that impacted the other monitoring site in Bellingham (Yew Street) even more. Good news for Bellinghamsters - particularly those living closer to the water. Bellingham has great air quality.

But looking at the daily averages reveals a bit about air quality in northwest Washington. The bad particulate air is nowhere near the railroad tracks.

The January 2013 air in Bellingham at the Cornwall site hear the railroad tracks was good every day. A few moderate days at the Bellingham Yew Street site. But the Columbia Valley site located in the Northwest Cascades between Sumas Mountain and Red Mountain had few good days and lots of days with unhealthy air.

The confined nature of the valley combined with winter temperature inversions and lots of readily available firewood bring about some of the worst if not the worst air quality in Washington State. There are no towns in the valley, but the valley has an urban growth area. The urban area was the result of a couple of semi failed recreational developments that turned into year round residential developments. The community is fairly poor and has a cold climate requiring heating, with wood being preferred by many.

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