This would include snowmobiles with four-stroke engines that meet or fall below sound and emission levels set by the Occupational Safety and Health Administration.

Jack Welch, president of the BlueRibbon Coalition, said the park's study found the carbon monoxide level of new machines at the west entrance was 2.1 parts per million and at Old Faithful 2 parts per million. OSHA standards allow for 35 parts per million. In the area of particulate matter, the new machines gave off 7.2 micrograms per cubic meter at the west entrance and 8.9 at Old Faithful. The acceptable standard is 65 micrograms.

"So you can see the new snowmobiles fall well within what has been set as acceptable levels of emission," he noted.

"As we looked at specifics of the ongoing challenge with sound, what our data showed was that manufacturers of BAT snowmobiles have done a good job, but the biggest challenge now involves older technology still in use, which involves the older snowcoaches," said Nash.

"They were built for standards that were appropriate when they were designed and built, but not now."

According to Nash, all roads will be open, with the exception of the leg between Canyon and Tower, which has been closed in the winter for many years.

"All other roads will be open and groomed this winter," confirmed Nash.

Clyde Seely, owner of the Three Bears Lodge in West Yellowstone, suggested that those planning a winter trip into the park call ahead and make reservations, "just to make sure they have one of the available openings for a specific day."

Snowmobiles remain the most popular method of transportation into the park in the winter.

A report from the winter of 2006-07 showed snowmobile visitors totaled 31,805 compared with 28,833 in the 2005-06 season for a 10.31 percent increase.

Snowcoach visitorship increased to 20,350 for the 2006-07 season from 19,856 in the 2005-06 season for an increase of 2.49 percent increase.

Those opting for snowcoaches will find significant changes have been made in their design and comfort in recent years. Seely said vans used for summer tours are, in fact, converted to winter use.

Newer coaches are much larger. In some cases they allow passengers to stand and move about and have wrap-around windows.

Those going into the park this winter can expect to see the usual array of wildlife.

The buffalo herd is currently at near-record levels. The latest count puts the herd at 4,700 animals. The high was 4,900 counted in 2005.

Elk, deer, moose and even wolf numbers are at stable numbers.

"Going into winter we have no wildlife issues outside of those we typically expect," Nash noted.

Which means wildlife remains abundant.

And, for now, and very likely in the future, this will be a part of the winter experience in Yellowstone for those on the seat of a snowmobile or inside a snowcoach.

For more information on winter visits to Yellowstone National Park visit www.yellowstone.com or www.nsp.gov/yell.

---

E-mail: grass@desnews.com