1998: The Hanford Advisory Board – a nonpartisan group that includes neighbors, Hanford workers, academics and tribes – sent a warning letter to the Energy Department and the Washington Department of Ecology in 1998, citing a "lack of leadership" in the effort to deal with the waste in the tanks and achieve cleanup goals.

2005: By 2005, Bechtel was three years into its struggle to build a Byzantine, first-of-its-kind waste-treatment plant – a 65-acre complex called the "Vit Plant" because, as The New York Times explained, it will "carry on a process called vitrification, in which the wastes, some of which will be radioactive for millions of years, are dissolved in an extra-strong form of glass and poured into steel canisters, which are then welded shut." There were unforeseen delays and myriad problems with the plant's design, which the company was still working on, even though construction had already started. The waste is so dangerous, much of the plant is supposed to be remote-controlled, so people need not enter it once it's operating. An Energy Department review of the plant's problems found "nuclear safety culture weaknesses," including "weak discipline in procedure compliance; ineffective training processes; inadequate procedures in some areas; and inadequate questioning attitude." The GAO released two more critical reports within a year, calling for improved efforts to protect the river and manage safety and costs. In one example, the Energy Department allowed Bechtel to move forward with the treatment plant's design and construction using incorrect seismic data – a mistake that cost nearly a billion dollars and set the project back for months.

2006: More than 50 experts – led by veteran engineer Walter Tamosaitis, who had more than 30 years' experience in chemical and nuclear plants – raised 28 technical issues with the waste-treatment plant's construction in 2006. Tamosaitis' team warned that the proposed system for mixing the waste sludge and liquid for treatment – using "pulse jets" that operate like turkey basters, sucking in waste and spitting it out – might cause an explosion. The waste contains bits of plutonium, along with cesium and water, which form highly explosive hydrogen gas when mixed.

In 2010, Bechtel declared that the key mixing issue was solved, but Tamosaitis continued to warn of the risk of explosion and other safety concerns. His bosses then transferred him to a makeshift office in a windowless basement room in an off-site office building. Complaining that his role had been reduced, he filed a whistleblower complaint and sued the main subcontractor, URS Corp., as well as Bechtel and the Energy Department. Judges dismissed those cases on technicalities, but Tamosaitis has appealed, seeking to get his story to a jury. Other watchdogs confirmed many of his concerns, but in 2013, URS laid him off, calling it a cost-cutting measure. The Tri-Cities Area Journal of Business summed it up: "Tamosaitis argued there is a culture in Hanford and DOE in Washington, D.C., to ensure short-term, career-enhancing goals are met regardless of whether any shortcuts will affect how the glassification complex works a few years later – long after the constantly-shuffling leaders have moved to other jobs and don't face the long-term consequence of their decisions."

2010: New York-based ProPublica revealed in 2010  that Hanford workers were being exposed to beryllium, a rare element whose dust is toxic when inhaled. ProPublica documented several cases of retaliation against whistleblowers – including medical professionals – who fought to protect workers decommissioning old buildings that contained the poisonous material.

2010: Also in 2010, safety inspector Donna Busche – a nuclear engineer and health physicist working for subcontractor URS – testified about the risk of explosions, as well as other problems in the treatment plant, during a hearing held by the Defense Nuclear Facilities Safety Board, an independent federal agency. The Energy Department's top environmental cleanup official reportedly excoriated Busche in front of other URS employees, and Bechtel and URS executives pressured her to change her testimony. Busche filed a whistleblower complaint, but more than a year later the Labor Department still hadn't responded, so Busche sued URS and Bechtel, alleging workplace discrimination. The company was too focused on "meeting deadlines regardless of the quality of the work," the lawsuit charged. "URS and (Bechtel) management viewed Busche as a roadblock (and) sought ways to retaliate against her," including reducing her authority and humiliating her. The Safety Board acted on the evidence, recommending full-scale testing of the treatment plant's pulse-jet mixing system and better sampling of tank waste to determine what's in the tanks and how to deal with it. Busche's lawsuit is still in court; a few months ago, she filed a second whistleblower complaint, alleging continued harassment.

2010: Another frustrated expert, Donald Alexander – a chemist in the Energy Department's Nuclear Safety Division – went public in 2011 with similar concerns about the waste-treatment plant, including the potential for a nuclear explosion and irreparable, corrosion-caused leaks in the pulse-jet containers. Rick McNulty, president of Local 788 of the American Federation of Government Employees, a union of Hanford scientists and engineers, responded by sending stop-work orders to the Energy Department and Bechtel, trying to prevent them from welding the tops on steel containers for the pulse-jet mixers. "It's a classic case of management overriding technical staff," McNulty told the Seattle Weekly. The bosses ignored McNulty's stop-work orders, and he retired. Meanwhile, the Defense Nuclear Facilities Safety Board released a new report generally backing the whistleblowers, finding that "DOE Contractor Management suppresses technical dissent."

2012: Nuclear chemical process engineer David Bruce, who'd worked for various Hanford companies for more than 40 years, and URS senior advisory engineer Murray Thorson went public with their concerns about the waste-treatment plant in 2012, including the risk of explosion and the possibility that pipes might clog or corrode and leak. "This sucker is not going to run as currently designed, plain and simple, and a heck of a lot of people around here know it but are too afraid to speak up," Bruce told the Seattle Weekly.

Bruce and Thorson were among many experts worried about the "black cells" – huge concrete containers that enclose the steel containers that enclose the pulse-jet mixers. Both types of containers will be so radioactive that, if problems arise once they're operating, they'll be extremely difficult – if not impossible – to fix. A few months later, acting on a complaint from an unnamed whistleblower, the Energy Department's inspector general found inadequate testing and recordkeeping on the welds on the black cells' containers, and unqualified workers doing safety inspections. Shortly after that, the agency's Office of Enforcement and Oversight uncovered numerous federal safety code violations at the plant. A few weeks later, Energy Secretary Steven Chu assembled yet another team of outside experts to review troubles at the plant, which led to several more teams studying specific problems with the black cells. The Energy Department even halted construction of the plant's major portions for a few months, and the GAO issued yet another report criticizing the agency for ignoring "unresolved ... technical issues" while allowing Bechtel "to earn incentive fees for meeting specific project objectives even as the project's costs and timelines balloon far beyond the initially planned goals."