The leaking of radioactive liquids at the Hanford, Wash., Nuclear Reservation is more extensive than previously reported, with six storage tanks affected, Washington Gov. Jay Inslee said Friday.

In a conference call with reporters Friday after a meeting with Energy Secretary Steven Chu, Inslee disclosed that six of the 177 tanks were leaking at the nuclear facility in Richland, in eastern Washington about 50 miles southeast of Yakima. 

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Inslee said Chu told him that evaluation system of the tank levels wasn't used correctly, raising the prospect that there may be even more leaks. But he said he was told that there was no immediate threat, a point the Energy Department reiterated in a statement Friday evening.

Hanford — which houses millions of gallons of radioactive waste left over from plutonium production for nuclear weapons — is already considered one of the most contaminated sites on Earth, the U.S. government says.

Last week, the U.S. Energy Department said that only one tank was leaking at Hanford.

"We need to get to the bottom of this," Inslee said. He called the disclosure "very disturbing news" and contended that the Energy Department needed a new plan to remove liquid from tanks that can't be repaired.

Sen. Ron Wyden, D-Ore., chairman of the Energy and Natural Resources Committee and an outspoken critic of containment efforts at Hanford, toured the site this week — before Friday's announcement — and judged conditions there "an unacceptable threat to the Pacific Northwest for everybody," NBC station KING of Seattle reported.  The Associated Press quoted Tom Towslee, a Wyden spokesman, as saying the senator will be asking the Government Accountability Office to investigate Hanford's tank monitoring and maintenance program.

An estimated 1 million gallons of waste has seeped out of the underground tanks and reached groundwater that will eventually reach the Columbia River, scientists say. The U.S. plans to build a plant to turn the waste into low-level radioactive glass for safe storage, but that facility is years behind schedule for its projected opening in 2019.

In a statement Friday evening, Inslee warned that the federal budget impasse — which could lead to a "sequestration," or cuts, of $1.2 trillion in federal spending over 10 years — made the Hanford predicament even more alarming.

"Frankly, the state Department of Ecology is not convinced that current storage is adequate to meet legal and regulatory requirements," Inslee said.

"With potential sequestration and federal budget cuts looming, we need to be sure the federal government maintains its commitment and legal obligation to the cleanup of Hanford," he said. "To see Hanford workers furloughed at the exact moment we have additional leakers out there is completely unacceptable."

Graham Robertson of NBC News contributed to this report. Follow M. Alex Johnson on Twitter and Facebook.

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This story was originally published on Fri Feb 22, 2013 6:26 PM EST

OLYMPIA, Wash. -- A tank that holds radioactive liquids is leaking at the nation's most contaminated nuclear site, Wash. Gov. Jay Inslee said Friday, raising concerns about the integrity of other storage facilities at the Hanford Nuclear Reservation.

The U.S. Department of Energy said liquid levels are decreasing in one of 177 underground tanks at the nuclear reservation. Monitoring wells near the tank have not detected higher radiation levels, the agency said. Inslee said the leak could be in the range of 150 gallons to 300 gallons over the course of a year.

"I am alarmed about this on many levels," Inslee said at a Friday afternoon news conference. "This raises concerns, not only about the existing leak ... but also concerning the integrity of the other single shell tanks of this age."

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The tanks hold millions of gallons of a highly radioactive stew left from decades of plutonium production for nuclear weapons.

Inslee said the state was told such problems had been dealt with years ago and were under control.

Energy Secretary Steven Chu said the federal government must not waiver in its commitment to clean up the highly contaminated site, Inslee told reporters.

The tank in question contains about 447,000 gallons of sludge, a mixture of solids and liquids with a mud-like consistency. The tank, built in the 1940s, is known to have leaked in the past, but was stabilized in 1995 when all liquids that could be pumped out of it were removed.

Inslee said the tank is the first to have been documented to be losing liquids since all Hanford tanks were stabilized in 2005.

At the height of World War II, the federal government created Hanford in the remote sagebrush of eastern Washington as part of a hush-hush project to build the atomic bomb. The site ultimately produced plutonium for the world's first atomic blast and for one of two atomic bombs dropped on Japan, effectively ending the war.

Plutonium production continued there through the Cold War, but today, Hanford is the nation's most contaminated nuclear site. Cleanup will cost billions of dollars and last decades.

Central to that cleanup is the removal of millions of gallons of a highly toxic, radioactive stew — enough to fill dozens of Olympic-size swimming pools — from 177 aging, underground tanks. Over time, many of those tanks have leaked, threatening the groundwater and the neighboring Columbia River, the largest waterway in the Pacific Northwest.

Construction of a $12.3 billion plant to convert the waste to a safe, stable form is years behind schedule and billions of dollars over budget. Technical problems have slowed the project, and several workers have raised lawsuits in recent months, claiming they were retaliated against for raising concerns about the plant's design and safety.

RICHLAND, Wash. -- The federal government says a one-of-a-kind plant that will convert radioactive waste into a stable and storable substance that resembles glass will cost hundreds of millions of dollars more and may take longer to build, adding to a string of delays and skyrocketing price tag for the project.

In addition, several workers at southeast Washington's Hanford nuclear reservation have raised concerns about the safety of the plant's design — and complained they've been retaliated against for voicing their issues.

The turmoil has some in the Pacific Northwest uneasy about the plant's long-term viability and fearful that a frustrated Congress could balk at paying more money for a project long considered the cornerstone of cleanup at the highly contaminated site.

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"The risk from the materials we are dealing with over there is simply too great (not to complete the plant)," Washington Gov. Chris Gregoire said in a recent interview with The Associated Press. "Here, we thought we were making such progress, and now to learn that, for reasons I don't know, we're at serious risk of missing more milestones is disappointing."

Issues raised by the whistleblowers about the plant's safety would be equally disconcerting, Gregoire said.

Roughly one-third of the federal government's entire budget for nuclear cleanup — about $2 billion each year — goes to Hanford, and nearly a third of that goes to construction of the plant. Last month, U.S. Rep. Edward J. Markey, D-Mass., demanded that the Energy Department provide an accurate statement of costs and schedule for the facility, and answer questions pertaining to safety complaints.

Markey is a senior member of the House Energy and Commerce Committee.

Dave Huizenga, the DOE's acting assistant secretary for environmental management, said the agency remains committed to building a safe, efficient plant. But he also said technical problems and differences of opinion are not unusual on a project so large and complex.

"We know we have to be really transparent with these issues, and they have to be addressed," he said. "We know the confidence that residents of the Pacific Northwest put in us. That rests with us every day."

The federal government created Hanford from a dusty stretch of land at the height of World War II, when thousands moved to the remote area for a top-secret project to build the atomic bomb. A city of thousands was born, and the site went on to produce plutonium for the bomb that was dropped on Nagasaki, Japan and for the nation's nuclear weapons arsenal throughout the Cold War.

Plutonium production also left behind a slew of waste and debris in trenches, buildings and underground tanks, making Hanford one of the most challenging cleanup projects in the world.

There have been successes in recent years. Spent nuclear fuel was removed from two water-filled pools near the Columbia River, dozens of buried waste sites have been dug up and workers continue to monitor and treat contaminated groundwater.

But the worst of the waste is still decades away from being completely removed. Millions of gallons of a highly radioactive stew — enough to fill dozens of Olympic-size swimming pools — are stored in aging underground tanks. Some of those tanks have leaked, threatening the groundwater and the river.

The plant is being built to convert much of that waste into glasslike logs — a process called vitrification — for permanent disposal underground. A massive undertaking, the plant will stand 12 stories tall and be the size of four football fields once completed, but technical problems have resulted in multiple delays and cost increases.

The price tag already has grown from $4.3 billion to $12.3 billion. The U.S. Department of Energy, which manages Hanford cleanup, recently announced additional costs of at least $800 million, as well as the possibility of additional delays.

The plant is currently scheduled to begin testing in 2019.

The revelations about higher costs and potential delays came as two Hanford workers filed suit as whistleblowers, claiming they were targeted for reprisals after raising safety concerns. The largest of the safety complaints deal with specifications for the process by which the waste would be mixed. The whistleblowers say, as specified, it could result in dangerous gas concentrations as well as a settling of waste within the mixing vessels.

Those issues largely center on a pretreatment building where the worst waste will be funneled before moving on to other parts of the plant. Any problems there would be significant because workers will not be able to enter certain areas once operations commence because of high levels of radioactivity.

Walt Tamosaitis, one of those whistleblowers, estimates the plant will end up costing taxpayers $20 billion because too many questions remain unanswered about the plant's overall design. He said his fear is that the plant, even after all that money, will not operate as it should.

"Congress should grab the Energy Department by the ears," he said. "Change has got to be made so that the plant operates safely and efficiently, which means it completes its mission in 40 years, and the safety culture has to change."

Tamosaitis called for work to stop on the pretreatment portion of the plant until all of the questions can be resolved.

The Energy Department maintains that any questions about gas buildup have been addressed, and a large-scale testing program has been launched to try to resolve the problems with the mixing vessels. Adequate mixing of the waste has been a technical concern for years.

Huizenga said the plant could easily begin operating without an immediate solution to the most troublesome waste, though he conceded that it's possible some waste may have to be mixed elsewhere, before it comes to the plant, which would be an added cost.

He also didn't rule out pausing construction on the plant's pretreatment facility if necessary.

"We're still concerned that we have these issues, and we're continuing to work them every day. We will not operate a facility that cannot be operated safely," he said.

Design of the plant is 85 percent complete, and construction is more than 50 percent complete.

A Defense Nuclear Facilities Safety Board review earlier this year raised concerns about the treatment of employees who raise safety concerns and recommended changes. The Energy Department's response is due next month.

A more recent report by an independent team of nuclear experts hired by Bechtel found no evidence that the contractor or the Energy Department had suppressed technical dissent by employees.

The number of technical issues that have been raised — and resolved — on the massive project far outnumber those that still remain, said Rick Kacich, Bechtel's assistant project director for integration. And the effort to find the best nuclear experts to review its design, which was created by hundreds of experienced engineers, speaks to the importance Bechtel has placed in the project, he said.

"There's really only one type of issue we can't solve, and that's the issue we don't know about," he said. "We not only encourage people, we expect them to raise questions about a first-of-a-kind facility."

Tom Carpenter of the worker advocacy group Hanford Challenge immediately criticized the latter report, calling it a "soft-pedaling" of the safety concerns.

He said the Energy Department and its contractors are too focused on meeting deadlines and ensuring that the contractors get paid their fees, over the objection of some of their best technical minds.

"It's unfortunate, because this is a plant that needs to work," he said. "We want the plant to work, they want the plant to work, but they're willing to take unacceptable shortcuts and punt to the future while they're building the plant. That's just not acceptable."

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