After five years of litigation related to repercussions of safety whistleblowing at the Hanford federal nuclear waste cleanup site, former URS Corp. engineering manager Walter Tamosaitis has reached a $4.1-million settlement with AECOM, which bought the firm last October.

The Aug. 12 deal comes less than one year before a trial in federal district court in Richland, Wash., was set to begin in Tamosaitis' latest suit against URS that stems from his 2013 termination.

The July 2016 trial was allowed after an appellate court last November reversed the lower court’s dismissal of Tamosaitis’ case.

The 22-year URS veteran convinced federal officials that Hanford’s $13-billion waste vitrification plant had major design and construction flaws. Work on it was halted in 2012.

A spokesman for AECOM said in a statement that the company settled with Tamosaitis "to avoid the cost and distraction of litigation relating to events that occurred over five years ago." He added that the firm "sttrongly disagrees that it retaliated against him in any manner."

Tamosaitis told ENR in an interview that the settlement is the largest for whistleblowing in the U.S. Energy Dept. nuclear complex and in Washington state, and that his case set a precedent to allow jury trials under a federal law covering nuclear facility whistleblowing.

He said his crusade also has resulted in DOE-wide reviews of and changes to site safety culture issues.

According to the settlement document, the payment to Tamosaitis includes compensation for back wages and about $1.1 million for "emotional distress and mental anguish."

Jack Sheridan, the Seattle-based attorney for Tamosaitis, the settlement "sends a messafe that integrity and truth are worth fighting for."

The engineering manager says he has not decided whether to return to URS, although the settlements allows him to. He says he may seek a role on a judicial advisory panel that will be reviewing technical issues related to mandates in a Hanford waste cleanup consent decree between the state and DOE.

Safety at all of our projects, including the waste treatment plant project, is our number one priority," said AECOM, adding that  "our strong nuclear safety and quality culture encourages both a questioning attitude and one’s right to hold a differing professional opinion."

Separately, in an Aug. 12 federal filing to the U.S. Securities and Exchange Commission, AECOM also disclosed, for the first time, Hanford-related litigation involving small business issues and site probes involving the firm.

Wall St. analysts following the publicly-held giant appeared surpise that the risks were not disclosed previously by URS before the acquisition but said the issues have been publicly noted in previous company updates or media accounts.

In a review of AECOM's overall third-quarter results, Baird & Co. analyst Andrew Wittman said that while bookings were "healthy," particularly in its Americas design unit, he noted cost pressure on its oil-and-gas construction business and "remains cautious of near-term earnings potential."

Jamie Cook, lead industry sector analyst for Credit Suisse, noted in an Aug. 14 report the AECOM "underperformed" the firm's group of followed E&C companies, down 4.3%. She said, however, that the firm's genration of free cash flow and its cost-cutting initiatives were positives.