The Department of Energy's decision to order all private occupants off Rattlesnake Mountain could create a big gap in Benton County's emergency communications system that would cost about $2 million to fix, according to county commissioners.

The county's communications transponder atop the 3,500-foot peak overlooking the Tri-Cities and the Hanford area is a critical piece of a five-tower system that encircles the region and provides blanket radio coverage for law enforcement and fire agencies.

County officials fear losing one of those towers because of DOE's eviction order would break the loop and leave large areas of the county without effective radio communications, said commissioner Leo Bowman.

"If it goes away, what happens to our system and how do we replace it and at what cost?" Bowman asked Thursday.

Hans Kwast, director of Benton County Emergency Services, said DOE's March 14 eviction notice gives his agency a little over two years to find an alternate tower site for its transponder because the current lease runs out in June 2010.

Building another tower elsewhere would take at least that much time and would cost as much as $2 million, Bowman said.

Emergency Services was one of 12 agencies notified three weeks ago that DOE plans not to renew their permits, licenses and easements on Rattlesnake Mountain.

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

Commissioners have reacted by approving a resolution calling for public input and comment, as well as congressional action in response to the public input before DOE takes any further action to evict tenants from the blustery peak.

Bowman said going to the public and getting members of Congress involved may be key to persuading DOE officials to back off.

The commissioners' resolution states the county "has been unwavering in its insistence that the public use of public resources be determined by the public and not by unilateral agency fiat."

"This is a public safety issue for all of this county, and we've got responsibility for back-up (notification) for the Umatilla Chemical Depot," Bowman said.

Rattlesnake's transponder is co-located with equipment owned by the Washington State Emergency Management Division and is housed in a building owned and maintained by DOE, said Valerie Eveland, a manager for Benton County Emergency Services.

The four other emergency system transponders are on towers on Prosser Butte to the west, Jump-Off Joe Peak just south of Kennewick, on the Umatilla Ridge south and west of McNary Dam, and at the emergency services dispatch center on Truman Avenue in Richland.

The five-point loop was created in the late 1990s as a strategic simulcast system. Each of the five transponders was positioned within line of sight of the others so radio signals would be sent and received without interference.

The Rattlesnake Mountain site is the highest point of the loop, Bowman said.

Kwast said replacing the Rattlesnake Mountain transponder may not even be possible with the current layout of the five-tower loop. "No one has done a coverage map yet. We may need two towers," he said.

If the tower at Rattlesnake Mountain goes away, radio signals from the Truman Avenue tower in Richland will not reach Prosser and vice versa, Kwast said.

"It is our expectation Congress will take a different view (from DOE's). We hope to put enough pressure on DOE to change their mind," Bowman said.