Yellowstone National Park will delay a much-debated winter-use plan and extend an interim plan that allows up to 318 snowmobiles and 78 snow coaches daily.

Yellowstone officials also said Friday they’ll allow another 30 days of public comment on the 400-page supplemental environmental impact statement, released June 29. Comment on the plan closed Aug. 20.

The decision maintains snowmobile and coach numbers this winter, Yellowstone spokesman Al Nash said.

“The rule was going to call for us to operate under the same rules and regulations for the next two years that we’ve had the previous three years,” Nash said. “We had a significant number of people who asked for more time. We want this to be a valuable, sustainable process and plan.”

Managing over-snow vehicles via what are called “transportation events,” Yellowstone’s plan would increase snowmobile traffic by 10 percent and reduce snow coach traffic by 23 percent. A “transportation event” is a single snow coach or group of snowmobiles averaging seven machines.

The Greater Yellowstone Coalition, which has criticized the park proposal, commended the delay.

“We certainly want them to get it right,” said Mark Pearson, the coalition’s conservation program director. “If taking more time means they’ll come up with the best scientifically defensible plan, that’s great.”

Pearson said one reason Yellowstone is delaying release of the plan is that air quality reports were released with “only a week or so left in the comment period.”

Jack Welch of the pro-snowmobile BlueRibbon Coalition provided a different reason. Welch said Superintendant Dan Wenk told him Thursday that the Environmental Protection Agency thought Yellowstone’s emissions testing “was flawed” and that the park “needed to do it again.”

“He said that they will be retesting the sleds and the snow coaches this winter,” Welch said.