The Bonneville Power Administration “allowed what could only be described as a culture of intimidation and mistrust in its human resources operation,” according to an Energy Department inspector general’s report released Tuesday.

Bonneville Power Administration, which is part of the Energy Department, tailored hiring criteria to bypass veterans, who are entitled to preference under guidelines issued by President Obama, according to the report.

The administration then retaliated against whistleblowers who questioned those hiring practices.

“Bonneville consistently manipulated the applicant rating process” in a way “that resulted in the inappropriate exclusion of veterans and other applicants from consideration for job selection,” the Energy Department’s inspector general, Gregory H. Friedman, said in the report.

Friedman said the investigation revealed that these prohibited practices were followed in at least 117 of 240 job openings, or 49 percent of recruitments conducted between November 2010 and June 2012.

In one case, a veteran was rated the “best qualified” candidate for a senior position. The manager who sought to fill the job and who favored another candidate closed the vacancy announcement and reopened it with new criteria that the veteran could not meet.

Instead of warning the manager not to follow this course of action, one of Bonneville’s staff attorneys provided advice on how to make sure the veteran would not qualify.

That case was just one example of how Bonneville had “misused overly restrictive qualifications to improperly eliminate qualified applicants from job consideration,” Friedman said.

The Bonneville Power Administration, though self-funded, falls under the Energy Department. Its 3,100 workers are federal employees.

Bonneville markets electricity generated by 31 federal hydropower projects and provides power to about 13 million people in the Pacific Northwest.

The new inspector general report comes less than three months after the Energy Department ousted Bonneville’s administrator and chief operating officer, putting them on administrative leave after they retaliated against six employees who were helping the inspector general’s investigation.

“The findings in the Department of Energy Inspector General’s report are deeply troubling to all of us at BPA,” Elliot Mainzer, Bonneville’s acting administrator, said in a statement. “The Department and BPA are fully committed to addressing the problems with our human capital management program and providing recourse to the many individuals, including veterans, who were impacted by our flawed hiring practices.”

Senate Energy and Natural Resources Committee Chairman Ron Wyden (D-Ore.) said that the report “confirms that Bonneville repeatedly and systematically violated federal rules giving hiring preference to veterans.” He added that “this is simply unacceptable. Our nation’s veterans deserve much better.”

In the report, Friedman charged Bonneville with “resisting” departmental oversight.

In preparation for one meeting between Bonneville and the Energy Department, a Bonneville official advised an executive in an e-mail dated February 2011 to avoid any discussions involving new human resources policies or Bonneville’s own policies, according to the report.

The e-mail stated, “you know that we try to keep our distance from [the department] on many fronts,” the report said. We do not take existing [department] HR policy as guiding. . . . And we consciously ignore some of their policy guidance when they try to sweep us under their purview.”