SACRAMENTO, Calif. (AP/CBS13) — A former Caltrans contract manager pleaded guilty Monday in what federal prosecutors said is an ongoing investigation into a bid rigging and bribery scam involving millions of dollars worth of contracts.

Choon Foo “Keith” Yong agreed to cooperate with the investigation into what prosecutors said was a conspiracy to rig the competitive bidding process for improvement and repair contracts at California Department of Transportation facilities.

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The scheme ensured that companies controlled by his co-conspirators submitted the winning bid and won the contracts, prosecutors said.

The contracts were cumulatively worth more than $8 million, and Yong’s agreement called for him to be awarded at least 10% of the value, according to his plea agreement.

He received cash bribes and other payments in the form of furniture, wine and remodeling services on his home, valued together at more than $800,000, prosecutors said.

He agreed to pay restitution as part of his plea deal in a scam that ran from early 2015 through late 2019, prosecutors said.

Assistant Attorney General Jonathan Kanter of the U.S. Justice Department’s Antitrust Division described Yong’s guilty plea as “the first in the Antitrust Division’s ongoing investigation into bribery and bid rigging at Caltrans.”

“Given the Infrastructure Investment and Jobs Act’s $1.2 trillion authorization and the critical role of transportation infrastructure in our nation, rooting out bid-rigging schemes that cheat the competitive bidding process remains a top priority for the division and its Procurement Collusion Strike Force partners,” Kanter added.

Caltrans officials did not immediately comment.

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The plea deal says Yong worked with “Contractor A, Contractor B and other co-conspirators,” without naming them. He would “submit the agreed upon bidders’ names — which always included Contractor A” for consideration. Another company would submit a “sham bid” so that Contactor A or another co-conspirator’s company would win the contract.

Contractor A would then pay money or provide other benefits to the co-conspirator bidders.

The agreement allowed Contractor A or another conspiring company “to win the Caltrans contracts at inflated prices,” according to the plea deal.

Yong was introduced to Company A in early 2015 by “Caltrans Employee A,” who then worked with him on the bid rigging, the plea deal says. He then paid her $500 a month in cash through at least early 2017 from his share of the take.

Yong retired from Caltrans in 2019, after starting work there in 1990, and the investigation began after his retirement, said his defense attorney, Tom Johnson.

“He’s looking forward to getting this behind him and moving on to the next chapter in his life. That’s why we entered the plea early,” Johnson said.

The joint investigation includes federal prosecutors and FBI investigators operating under the Justice Department’s Procurement Collusion Strike Force, created in November 2019. Kanter said its role has grown in importance since Congress last year approved the $1.2 trillion Infrastructure Investment and Jobs Act.

Yong is set for sentencing in August. The charges carry a maximum penalty of 10 years in prison plus a $1 million fine or twice the financial loss.

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As part of the plea deal, prosecutors agreed to recommend a sentence at the low end of the federal sentencing guidelines, plus an additional reduction for his cooperation.