Federal investigators said Thursday the region's airports authority is afflicted by a "culture of favoritism" that led to widespread nepotism, mismanagement and questionable contracting practices at an agency overseeing the Dulles Rail project, one of the largest public works programs in the country.

The final report from the Department of Transportation's Office of Inspector General shows that Metropolitan Washington Airports Authority senior staff picked favorites among contractors -- at one point giving a contract to a firm that was charging as much as 234 percent more than other bidders.

The authority awarded 64 percent of its contracts worth more than $200,000 without full and open competition, the report said. Five of those deals were no-bid contracts with a combined value of $6 million.

Bad management led to a host of problems at the authority, investigators said. Contractors were told to start work before their contract actually began, which led to the authority paying one contractor $572 an hour while the contractor sat through a five-hour board meeting at which he was actually awarded the contract.

The report also detailed ethical failures of employees, showing that the airports authority's vice president of human resources, Arl Williams, directly hired a relative and kept the relative in the job even thought that person failed a criminal background check. As The Washington Examiner first reported Thursday, Williams announced his retirement Wednesday, the day before the inspector general's report was released.

The investigation also revealed that one airports executive and his staff accepted about $12,000 in gifts over four years from a major contractor doing business with their department --including two tickets to the 2009 Super Bowl, hotel and travel fees, four trips to golf tournaments, a trip to New York City to attend a baseball game, tickets to 19 other major sporting events and three concerts, a fishing trip and 17 social events with food and beverages.

The authority also failed to do criminal background checks or hired those who did not clear such a check, the report shows. One manager was hired with a salary of $135,000 and given access to sensitive and personal information despite having a criminal record.

Senior authority staff also gave out high salaries without consideration to the agencies' own compensation rules and one executive assistant with a relationship with a former board member was given a full-time job and a $15,000 raise without justification, investigators said.

Rep. Frank Wolf, R-Va., who called for the investigation, and Virginia Gov. Bob McDonnell, a critic of the agency, said the report validates concerns that they have been raising for years.

"Unfortunately, actions on the part of certain members of the MWAA board of directors, a general lack of transparency and accountability, and employee misconduct have jeopardized the public's confidence in the authority's ability to ethically manage its critical assets and complete the Dulles Rail Project," McDonnell said in a statement. "The concerns that I have expressed over the past two years are, unfortunately, validated by the U.S. DOT inspector general."

Wolf said he would continue to push for accountability at the authority and make sure it follows the inspector general's recommendations."

"The problems are very serious, and I think they have to carry out all of the recommendations," Wolf said.

The airports authority plans to hold a press conference Thursday afternoon to comment on the report.