ROCK SPRINGS -- As expected, members of the Utility Workers Union of American soundly rejected a proposed three-year contract offer from Rocky Mountain Power Co.

More than 93 percent of the members of the Local 127 union voted on the contract.

Of that number, 98 percent voted against the contract language, according to the ballot counted Friday.

The main objections, according to a media release from the union, were a freeze on the defined benefit pension plan, increases in medical premiums and deductibles' loss of vacation and bereavement pay, among other issues.

Local 127 represents the majority of union employees of Rocky Mountain Power and PacifiCorp Energy in the state of Wyoming.

The union represents 587 employees at three PacifiCorp power plants -- Jim Bridger Power Plant east of Rock Springs, Dave Johnston near Glenrock and Wyodak near Gillette -- and transmission line workers across the state.

Contract negotiations will begin again on Nov. 19, the union release said.

Both the union and the company expected the contract vote to fail.

Rocky Mountain Power President Richard Walje said recently that the two sides would return to negotiations if the employees failed to ratify the contract.

"But I fully expect to reach a resolution at some point," Walje said earlier.

Both sides said they hope to avoid a strike.

The two sides started the collective bargaining process in August.

The union has been working under a three-year contract first approved in 2004 and extended for two years in 2007.

The contract expired Sept. 25 but employees have continued to work under the old contract.

Rocky Mountain Power, a division of PacifiCorp, serves about 132,000 utility customers in Wyoming and employs 1,389 workers in the state.