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. 

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."

Mark Ralston / AFP - Getty Images file

The Hanford site in eastern Washington is considered one of the most contaminated locations on Earth.

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