RICHLAND -- Bechtel National has taken disciplinary action against four managers at the Hanford vitrification plant for reportedly eavesdropping on a meeting between safety representatives and the Department of Energy.

An investigation was begun by Bechtel 12 days ago after an anonymous call was made to an employee concerns program.

The incident involved safety representatives appointed for a new program established in late 2007 at the vitrification plant with DOE's encouragement after a similar program worked well elsewhere at Hanford.

Construction workers at the vit plant picked five worker representatives who Bechtel management approved to be an extra set of eyes on safety issues, according to Bechtel. In addition to their construction jobs, they discuss safety issues and concerns from the workers' perspective with Bechtel management.

In July, the five safety representatives were scheduled to meet with Shirley Olinger, the manager of DOE's Hanford Office of River Protection. When she couldn't make the meeting at the plant, she asked workers if they instead could come into Richland.

During the meeting, one of the safety representatives' managers called a worker's cell phone to find out where he was. The worker's cell phone was inadvertently left on after the call was answered, said Bechtel spokesman Drew Slaton.

That manager and three others then listened to at least a portion of the conversation without the knowledge of the safety representatives or Olinger, according to Bechtel.

"I do not condone this behavior and it is contrary to Bechtel's Standards of Conduct and Business Ethics, our culture and my expectations of our ... staff," said Bill Elkins, project director for the Waste Treatment Plant, in a message sent to staff Thursday.

Bechtel has an open-door policy that encourages employees to raise safety and other concerns, Slaton said.

When Bechtel learned of the incident it launched an investigation that called in its employee concerns group, its corporate ethics officer and its human resources department.

"It was a very thorough investigation," Slaton said.

Elkins expects every employee to adhere to the highest ethical conduct, the project director said in his message to employees.

"There is no room for discussion or debate on this matter," he said. "Violations of our ethics policy are grounds for serious disciplinary action."

Bechtel declined to say what disciplinary action was taken because it was a personnel issue. Disciplinary actions varied for the different managers involved and none was fired, Slaton said.

Bechtel also did not release the names or positions of the managers involved.

"The Office of River Protection feels Bechtel has taken prompt and appropriate actions to resolve this matter," said Erik Olds, spokesman for DOE.

The Office of River Protection will continue to build trust with the Hanford work force and maintain an open-door policy for all workers, he said.