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EPA Raises Concerns Over Yellowstone National Park's Winter-Use Calculations


The lexicon built around enjoying the winter season in Yellowstone National Park grew this year when park officials coined "transportation events" to help define the impacts of snowmobiles and snowcoaches. But that phrase has even Environmental Protection Agency officials scratching their heads over exactly what it represents.

In working through a fifth environmental impact statement geared towards crafting a reasonable winter-use plan for the park, Yellowstone officials chose to "manage oversnow vehicles by their overall impacts to air quality, soundscapes, wildlife, and visitors, rather than focusing solely on the number of snowmobiles and snowcoaches allowed in the park each day."

To do so, park planners defined a "transportation event" as equaling one snowcoach or seven, (on average, or no more than 10), snowmobiles entering Yellowstone on a given winter say. Under the Draft Winter-Use Supplemental Environmental Impact Statement, up to 110 'transportation events' would be permitted a day.

In their comments on the plan, EPA officials questioned park officials on how they came up with their "transportaton events."

“The EPA was unable to determine how the NPS established thresholds for the maximum number of transportation events per day for the preferred alternative,” EPA officials wrote in a letter obtained by the Jackson Hole News & Guide. “Additionally, we could not ascertain the basis for establishing the maximum number of 10 snowmobiles per event.”

EPA officials also raised questions over why the park, in collecting emissions data from snowcoaches and snowmobiles, included a 2008 Chevy snowcoach when that model would not be allowed in the park's approved 2018 fleet. The Chevy's emissions, the EPA noted, "significantly increases" the overall emissions projections calculated by the park.

Yellowstone officials last week announced that they intended to extend a temporary winter-use plan for the coming winter season under which 318 snowmobiles and 78 snowcoaches would be allowed into the park on any day. They also said they would take additional public comment on the draft winter-use plan.


I guess I just don't understand how 318 snowmobiles and 78 snowcoaches are worse for the Park than 10,000 automobiles in the summer. In my totally unscientific opinion, it just seems like there are a group in the NPS that is influenced by far left eco's to turn the park into no human activity in the winter. I imagine they know that the rebellion to limit autos in the summer would lead to congressional retalliation. Just don't understand and I do not think they can scientifically show that winter use is worse than the congested summer use.

The scale of the pollution documented in YNP was remarkable. Snowmobiles were responsible for 68% to 90% of HC emissions and 35% to 68% of CO emissions each year (NPS 2000), but make up only 6% of the total vehicles entering the park annually. On a peak day in YNP, snowmobiles released approximately 20 tons of hydrocarbons (HC) and 54 tons of carbon monoxide (CO) into the air (NPS 2000). For comparison, in an average day in July, cars in YNP emit 2.5 tons of HC and 17.9 tons of CO (NPS 2000). While the snowmobile season usually only lasts three months in YNP (mid-December to mid-March), their emissions equaled or exceeded the total annual emissions for CO and HC from other mobile sources combined (cars, buses, and snow coaches).

While I haven't been to Yellowstone in winter, I have contributed to the 10.000 cars in summer. Judging from my experience there and winter travel elsewhere, I assume that the most precious thing in Yellowstone's winter, that gets endangered by over the snow travel is the sound scape. Snowmobiles are loud. Much loader than most cars. And as the winter use in Yellowstone is restricted to a few places within the park, the soundscape there is influenced by them in a very negative way. The two stroke engines, that could be smelled over hundreds of yards and almost an hour, are gone by now. But the sound remains an issue.

Having been fortunate to spend five days on snowmobiles in Yellowstone in February, 2011 I can tell you that the snowmobiles being used were incredibly quiet. I heard other more powerful snowmobiles in West Yellowstone that were very loud but not the ones they now allow in the Park. The experience of being in Yellowstone in the Winter is incredible and while I very much want to protect the environment and wildlife in all our Parks, I did not see that the snowmobiles or snowcoaches caused any undue burden on either.

From a sound pollution standpoint what I cannot understand are the very, very loud motorcycles that take over all Parks they enter. These motorcycles can be heard from miles away even in the backcountry of most National Parks. In the Smokies it is very difficult to get away from the sound of these motorcycles including the exhaust and the radios that blast away over the sounds of the exhausts. If we want to reduce noise pollution, lets start with motorcycles that are modified to be loud!

Anonymous, you may have posted supposed facts or whatever you want to call them but they are for the 2 stroke snowmobiles prior to 2000 and there have been no 2 strokes allowed in the park for several years and the 4 strokes currently allowed to run in the park weren't commercially produced until 2002 so your data does not represent the current snowmobiles allowed in the park at all.

My question is why is the EPA concerned about including a 2008 snowcoach if it will not meet the 2018 emissions? The same thing should be asked then why is the EPA concerned about the current snowmobiles because they also are not going to meet the 2018 emissions standards and cleaner ones will need to be built. Why are they questioning the inclusion of a snowcoach if they aren't going to question the inclusion of the snowmobiles that aren't going to meet the 2018 standards?

MRC should go to Yellowstone in the winter and enjoy it. Arctic Cat started using an automotive engine in their snowmobile originally to meet the Yellowstone standards. Why would an automotive engine be so much louder in a snowmobile than in an automobile MRC? I have a snowmobile and a Suzuki automobile with the exact same engine in them and asked my U.S. Senator the same thing. They start the same and you can not distinguish which one is the snowmobile and which one is the automobile MRC. It really opened my Senator's eyes when shown the facts because it you were to do a blind test you wouldn't know which one was which as it is the same engine.

Like RKT said if sound is an issue then why aren't they after some of the motorcycles in the summer time?

I will continue to say if noise is an issue for you when visiting Yellowstone then the best time to visit the park is in the winter because it is much quieter than the summer period. Go ENJOY!!! Read RKT's report above, you will see the word is getting out it isn't as bad as the ones saying to ban snowmobiles say it is.

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