December 11, 2003: National Park Service Announces Rules for Snowmobiles in Yellowstone Park

The National Park Service issues a final rule announcing that the number of snowmobiles permitted in Yellowstone Park will be restricted to 950 per day when parks open for the winter season on December 17. Eighty percent of the sleds must be commercially guided and meet “best available technology” (BAT) requirements. The remaining twenty percent will not have to be BAT. For the 2004-2005 winter, regulations on the maximum daily number of snowmobiles will remain the same, except that all snowmobiles will be required to meet BAT standards. Similar rules will be imposed on the use of snowmobiles in Grand Teton National Park and the John D. Rockefeller, Jr., Memorial Parkway. [National Park Service, 12/11/2003] The decision is made in spite of the fact that independent federal studies had previously determined that reversing the Clinton-era phase-out would result in a significant increase of carbon monoxide pollution and nitrogen oxide emissions. [Caspar Star Tribune, 2/21/2003]