AY-102 is causing a lot of controversy at Hanford. The leaking double-walled tank is not a hazard to the public according to the Department of Energy, but some former Hanford workers are calling it a "catastrophic" event.

Over the last weekend during pumping of hazardous waste from tank AY-102, alarms sounded at Hanford, prompting workers to lower a camera into the space between the two walls of the double-shelled tank, which dates back to the 1970's. The alarm sounded around 3:30am last Sunday.

The 2-foot space between is called the annulus. When crews turned on the camera, they found an eventual total of 8.4 inches of toxic waste that had leaked. 

AY-102 is the most problematic of the some 177 tanks at Hanford that hold radioactive toxic waste leftover from World War II nuclear weapons production, and subsequent activities of the N-Reactor (which produced both electricity and plutonium for nuclear bombs) and other reactors.

The Department of Energy has said the leaks post "no immediate or near term health risks,but other opinions differ. 7 tanks have found to have leaks, including six older single-shell tanks, and the one double shell, AY-102.  This tank is particularly worrisome because the double-shell tanks are supposed to be much sturdier. A lot of radioactive toxic waste was pumped from the single-shell tanks into the doubles for safety reasons til it could be property treated and disposed of.

Mike Geffre, who retired in 2013 after 26 years at Hanford's tank farms, was the worker who first discovered the formerly tiny leak in AY-102 in 2011. KING-5 TV's investigative report in 2013 found that Washington River Protection Services (WRPS) reportedly ignored his findings until 2012. Washington State Department of Ecology has been pressuring the DOE to pump out AY-102 because of the leak.

DOE officials say the pumping, which began three weeks ago, could have 'shaken' or disturbed the tank, triggering more leaking, which they say is a possibility they knew could happen. According to officials the waste leaking was about 8.4 inches deep in the space between the two walls. Previously, the leak was so slow the waste would dry up, leaving a crusty salt-like layer. But this leak was far more significant and deep.

Geffre says it's the most significant event to happen in the history of the tank farms, some reports claim this latest leak amounts to as much as 3,500 gallons. The tank still has about 20,000 gallons left to be pumped. AY-102 does not have a venting or filtration system to siphon off gasses created by the toxic sludge, and Geffre says the "Hazards to workers just went up by a factor of 10."

Numerous checks of safety and monitoring systems have not shown any definite evidence that the outer shell has leaked, or any of the sludge has escaped the confines of the double shell area, but there are some areas it could have that are not accessible.

The tanks at Hanford hold a variety of some 2,000 toxic chemicals punctuated by radioactive uranium and plutonium waste. It's considered the most toxic blend of waste on Earth.

So, is the leak significant but not a major hazard, as says DOE? Or, is it the first step or latest symptom in what many former workers say is a far more serious problem than what the government is letting on?  Only more exploration, testing and potential 'events' will show what's really happening.

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