New scientific findings of the National Park Service show that snowmobile noise has exceeded Yellowstone's standards for 3 consecutive winters, even though the actual number of snowmobiles in the park has declined. According to report by the National Park Service, available at
www.nps.gov/yell/parkmgmt/upload/final_soundscape.pdf, snowmobile noise was audible at Old Faithful between 60-80% of the time between 8 a.m. and 4 p.m. for almost the entire '05-'06 winter season. The noise at Old Faithful occurred with an average of 263 snowmobiles present on each of the sampling days. The average number for the past 3 winters is only 250 per day.
The issue is currently being considered. To read more about this issue go to
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