The tank is known as AZ 101 and was put into service in 1976. The tank’s life was expected to be 20 years. Now it has been holding hot, boiling radioactive and chemically contaminated waste for 41 years.

As King5 reports, a seven-person crew was undertaking a routine job around 7 p.m. Thursday night. They had deployed a remote controlled devise into the safety space of what is known as a double shell tank.

The device is used to evaluate structural integrity of the aging tanks. Normally, equipment lowered in this two-foot wide outer shell of the tank comes up clean. But not this time. A radiation specialist on the crew detected higher than expected readings.

“Radiological monitoring showed contamination on the unit that was three times the planned limit. Workers immediately stopped working and exited the area according to procedure,” said Rob Roxburgh, deputy manager of WRPS Communications & Public Relations, the government contractor in charge of all 177 underground storage tanks at the nuclear site.

“Everybody was freaked, shocked, surprised,” said a veteran worker, who is in direct contact with crew members. “(The contamination) was not expected. They’re not supposed to find contamination in the annulus (safety perimeter) of the double shell tanks.”

“We are of course concerned it might be a leak,” a Washington state Department of Ecology spokesperson said.

The AZ 101 contamination event comes just 10 days after a tunnel collapse at Hanford that caused a site wide emergency. On May 9, workers found a 20 by 20 foot cave in of a tunnel used to store highly radioactive and chemically contaminated equipment from the Cold War-era.

a worker’s clothing was exposed to radioactive contamination at the site late Thursday, in what Gov. Jay Inslee called an “alarming incident” that should prompt federal officials to expedite their cleanup of the decommissioned facility. Worse still, as The Wall Street Journal reports at the site late Thursday, in what Gov. Jay Inslee called anthat should prompt federal officials to expedite their cleanup of the decommissioned facility. Detection equipment was then used to check for contamination that might have become airborne and adhered to the workers.

They found radioactive material on one worker in three spots: on one shoe, on his shirt, and on his pants in the knee area. According to workers in the field, the contaminated items were removed, bagged and appropriately disposed of.

Governor Jay Inslee called on the federal government to investigate after the contamination was discovered.”This comes on the heels of last week’s tunnel collapse. It is another urgent reminder that Congress needs to act, and they need to act quickly.”

“The May 9th incident should serve as an urgent reminder of the challenges in cleaning up the Hanford site that require a rededication of attention and resources in order to ensure progress continues moving forward,” the governors said in their letter to the Republican president.

“The longer it takes to clean up the facilities and structures that store mixed chemical and radioactive waste, the farther and farther they get past their useful lives – causing degradation and more risk of failing.”