PORTLAND -- Tribal concerns and the need to spend Hanford cleanup dollars on the Rattlesnake Mountain road led to a decision to end private use of the mountain, according to the Department of Energy.

"It is a sacred site," said Gabriel Bohnee, who represents the Nez Perce tribe on the Hanford Advisory Board.

The board discussed DOE's decision to clear the mountain of structures, including a nonprofit observatory, at its meeting this week in Portland.

The issue came up when board member Pam Larsen, who represents Richland, read a list of concerns she heard from residents after eviction notices were sent March 14 to 12 agencies using the mountain.

The tribes which historically used the mountain -- which is in the security perimeter of the Hanford nuclear reservation -- want it protected, along with Gable Butte and Gable Mountain in the production portion of the reservation, said Doug Shoop, deputy manager of DOE's Hanford Richland Operations Office.

The Nez Perce, Yakama and Umatilla tribes and the Wanapum band share a common history with Rattlesnake Mountain that goes back more than 9,000 years, said Armand Minthorn, who represents the Confederated Tribes of the Umatilla Indian Reservation on the board.

The tribes' and band's written and oral histories tell of the significance of the three mountains on the Hanford site, Bohnee said.

Rattlesnake Mountain "is a site we're taught to respect," but it has been a long, difficult process to get DOE to understand its significance, he said.

"Now good work is being done to protect the mountain," Minthorn said. Protecting the mountain benefits everyone, he said.

Because the mountain was included in Hanford's security perimeter when the site was picked for the nuclear reservation in World War II, it has had little use and most of it remains in nearly pristine condition.

The mountain is closed to the public, but its top is used for communication towers under licensing agreements with private companies and government agencies that typically hold five-year leases. It's also the home of a 0.8-meter Cassegrain telescope in an observatory built by Battelle Memorial Institute in 1971 for astronomical research.

Battelle donated the observatory to the nonprofit Alliance for the Advancement of Science Through Astronomy, AASTA, in 2005.

AASTA and agencies that have leases on the mountaintop must reach it by entering a locked gate and drive up a steep and winding one-lane road.

The road has been a problem for DOE, Shoop said. The only money it has to maintain the road comes from funds intended for the cleanup of contamination at Hanford left from the past production of plutonium for the nation's nuclear weapons program.

In addition to routine maintenance, such as plowing the road in winter, the deteriorating road needs to be improved or replaced if DOE continues to allow private and commercial access to the mountain top, Shoop said.

The decision to require the observatory to be removed from the mountain appears to have been made in a vacuum, said Rick Jansons, who represents the Benton-Franklin Council of Governments on the Hanford Advisory Board. DOE needs to take a step back from its decision and let the public have a say, he said.

That was one of the concerns raised in the comments read by Larsen.

The public was "blindsided" by the decisions that tenants must leave the mountain and remove manmade structures as their leases end, according to the comments Larsen compiled.

DOE said last month that the announcement was consistent with a 1999 land-use study and decision that the Arid Land Ecology Reserve, which includes the mountain, should be managed for preservation.

However, the preservation alternative in the study allows for limited public access consistent with resource preservation, according to the comments. Preservation also may include "improvements in the quality of life, new educational and research opportunities and benefits associated with eco-tourism," according to the DOE Hanford Comprehensive Land Use Plan.

The decision to clear the mountain also appears to be inconsistent with DOE's 1977 designation of the Arid Lands Ecology Reserve as part of DOE's Hanford National Environmental Research Park, according to the comments. It is one of seven such U.S. parks for research and education outreach by scientists and educators.

DOE's move to clear the mountaintop comes as the U.S. Fish and Wildlife Service, which manages the mountain for DOE as part of the Hanford Reach National Monument, is preparing a management plan that will outline planned use of the monument.

However, DOE, not Fish and Wildlife, is responsible for the use licenses, Shoop said. He also pointed out that DOE did not take public comment before approving leases of the mountain top. Public comment was accepted on the 1999 comprehensive land-use plan.

DOE has stressed that it plans to work with AASTA and other agencies to allow enough time to find places to move their structures and minimize costs. Clearing the mountain will not be a quick process, Shoop said.

There has been some discussion among agencies to work together to find a common new location for communication towers, he said.