Zero Progress On Snowmobile Emissions Since 2001 In Yellowstone

New snowmobiles haven't lived up to Yellowstone National Park officials' hopes that they'd be cleaner and quieter than four-stroke machines produced in 2001. Those technological advances provided a crucial underpinning to the park's approach to snowmobiling in Yellowstone. Previous park plans said the newer machines should provide a 90 percent reduction of hydrocarbon emissions and a 70 percent reduction in carbon monoxide when compared with the older two-stroke machines.

When those “best available technology” goals were set, the National Park Service expected that snowmobile emissions would continue to get better. “However, there have been no improvements in snowmobile air or sound emissions since four-strokes were introduced in 2001,” according to a Park Service presentation that has been given to different interest groups.

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Although newer model four-strokes are an improvement over the two-strokes, the amount of carbon monoxide emissions “still far exceeds what a late-model sedan or light duty truck emits. Even cleaner snowmobiles could be a target for the future,” the report said. The study, prepared by researchers at the University of Denver, also looked at pollution from snowcoaches. Researchers said many of the snowcoaches they tested were older models and “should not be construed as adequately representing the average snowcoach fleet used in the park during the winter months.”

Of those tested, snowcoaches emitted 1.2 times more carbon monoxide per person when compared to the average pollution per person riding a 2005 snowmobile. But when comparing the least-polluting snowmobile with the least-polluting snowcoach, the snowmobile put out 41 times more carbon monoxide than the snowcoach.

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http://www.billingsgazette.com/index.php?tl=1&display=rednews/2006/01/26/build/wyoming/20-snowmobiles.inc

if all those rosy predictions about "technology advances" were just a politically convenient strategy for avoiding the debate.