$12.3 Billion Hanford Plant Sees New Costs, Delays A new cost estimate and construction schedule for a massive waste plant being built at the nation's most contaminated nuclear site will be delayed at least a year as workers try to resolve serious technical problems raised by whistleblowers about design and safety, the U.S. Department of Energy said Tuesday. The $12.3 billion plant at south-central Washington's Hanford nuclear reservation is being built to convert highly radioactive waste into a stable glass form for permanent disposal underground. The plant is currently scheduled to begin operating in 2019, but several workers have raised concerns about safety, particularly about erosion and corrosion in tanks and piping inside the plant. The issues are significant because the problem areas are inside so-called black cells, which will be closed off and inaccessible due to high radioactivity after the plant begins operating. The Energy Department and its contractor hired to build the plant, Bechtel National Inc., have been working to develop a new price tag and construction schedule for the plant in light of those problems. However, the Energy Department announced in a conference call Tuesday that the new estimates will be delayed at least a year as it embarks on additional tests to resolve the issues. The tests are expected to cost tens of millions of dollars. The federal government created Hanford in the 1940s as part of the top-secret project to build the atomic bomb. The site produced plutonium for the world's first atomic blast and for the bomb that was dropped on Nagasaki, Japan, to end World War II. Today, it is the nation's most contaminated nuclear site, with cleanup expected to last decades. Central to that cleanup is 53 million gallons of highly radioactive waste left from decades of plutonium production for the nation's nuclear weapons arsenal. The waste is stored in 177 aging, underground tanks, many of which have leaked, threatening the groundwater and nearby Columbia River. Building a plant to convert that waste into a solid, stable form has been among the most challenging tasks at the site. The project has involved numerous technical problems, delays and cost increases. More recently, several workers raised safety concerns and two filed a lawsuit as whistleblowers, saying they were targeted for reprisals for raising questions. In addition to erosion and corrosion, problems remain unresolved with adequate mixing of the waste. "We're all, frankly, disappointed that this waste stream is so complicated and it's causing us these kind of issues and these kind of problems," said Dave Huizenga, senior adviser for the agency's Office of Environmental Management. But I think we're addressing these with a group of technical experts and our contractor. In March, the Defense Nuclear Facilities Safety Board ruled that the agency lacks necessary information to resolve some problems and establish a complete safety plan. Design of the plant is 85 percent complete, and construction is more than 50 percent finished.