A leak in a massive nuclear waste storage tank at the Hanford Site has expanded significantly, KING 5 learned this weekend.

After leak detector alarms sounded early Sunday morning, crews at Hanford lowered a camera into the two-foot-wide space between the tank's inner and outer walls. They discovered 8.4 inches of radioactive and chemically toxic waste has seeped into the annulus.

The U.S. Department of Energy released a statement Monday calling the leak an "anticipated" outcome of an ongoing effort to empty the tank in question. The Washington state Department of Ecology said, "There is no indication of waste leaking into the environment or risk to the public at this time."

But one former tank farm worker said the leak should be considered a major problem.

“This is catastrophic. This is probably the biggest event to ever happen in tank farm history. The double shell tanks were supposed to be the saviors of all saviors (to hold waste safely from people and the environment),” said former Hanford worker Mike Geffre.

Geffre is the worker who first discovered that the tank, known as AY-102, was failing in 2011. In a 2013 series, “Hanford’s Dirty Secrets," the KING 5 Investigators exposed that the government contractor in charge of the tanks, Washington River Protection Solutions (WRPS), ignored Geffre’s findings for nearly a year. The company finally admitted the problem in 2012.

Until now, the leak found by Geffre was very slow. The liquid would almost immediately dry up, leaving a salt-like substance on the floor of the two-foot space between the tank's walls, called the annulus.

Approximately three weeks ago, work began to pump out the contents of AY-102, which has the capacity to hold one million gallons of the deadly waste. The state of Washington has been pressuring the federal government, which owns Hanford, to pump out AY-102 for three-and-a-half years because of the cracking and slow leaking discovered by Geffre in 2011. Sources told KING the disturbance caused by the pumping must have exacerbated the leak: essentially blowing a hole in the aging tank allowing the material to leak more quickly into the outer shell.

Tank AY-102 is one of 28 double-shell tanks at Hanford (there are 177 underground tanks total) holding nuclear byproducts from nearly four decades of plutonium production on the Hanford Nuclear Site, located near Richland. Initially the plutonium was used to fuel the bombed dropped on Nagasaki, Japan, in World War II.

Plutonium production continued throughout the Cold War. Since 1989 the work at Hanford has focused solely on cleanup – the most difficult being getting rid of the liquid waste left behind that threatens the health of people, wildlife and the environment, including the nearby Columbia River.

The new leak poses problems on several fronts. The outer shell of AY-102 does not have the exhaust or filtration system needed to keep the dangerous gases created by the waste in check. Workers have been ordered to wear full respiratory safety gear in the area, but the risk remains.

“The hazards to workers just went up by a factor of 10,” said Geffre.

In addition, the breakdown calls into question the viability of three other double-shell tanks at Hanford that have the exact design of AY-102.

“The primary tanks weren't designed to stage waste like this for so many years,” said a current worker. “There’s always the question, ‘Are the outer shells compromised’”?

The accumulation of waste in the outer shell also means the deadliest substance on earth is that much closer to the ground surrounding the tank. And currently there is no viable plan in place to take care of it.

“It makes me sad that they didn’t believe me that there was a problem in 2011,” said Geffre. “I wish they would have listened to me and reacted faster. Maybe none of this would be happening now. It’s an example of a culture at Hanford of ‘We don’t have problems here. We’re doing just fine.’ Which is a total lie,” said Geffre.

Full statement from Dept. of Energy:

The U.S. Department of Energy (DOE) and Hanford tank farms contractor Washington River Protection Solutions (WRPS) are evaluating recently identified, anticipated changes in the amount of waste between the inner and outer shells (the annulus) of Hanford double-shell tank AY-102.

Since March 3, DOE and WRPS have been retrieving waste from Tank AY-102, and to date approximately 95 percent of the material has been retrieved.  Early on the morning of April 17, crews identified an increase in the waste level in the tank’s annulus. Early on the morning of April 18, a slight decrease in the height of the waste in the annulus was detected. Out of an abundance of caution, DOE and WRPS are in the process of evaluating the tank’s condition.

DOE and WRPS are committed to ensuring the safety of the Hanford workforce, the public and the environment.

WA Dept. of Ecology statement: