Saturday 3 August 2013

Hanford


The Plutonium Gang: CH2M Hill Dismantles the Hanford Nuclear Site



1 August, 2013

Before entering the shuttered Plutonium Finishing Plant at the Hanford Site, Jerry Long hangs his identification badge on a board outside the entrance, so rescue crews can easily figure out who’s inside, should it come to that. “This is a no-kidding hazardous category 2 nuclear facility,” says Long as he enters a brightly lit room furnished with rows of metal chairs and benches. The U.S. Department of Energy reserves that category for sites that might blow up, or, as they like to call it, experience a “criticality event.”

Rolling racks of neatly folded cotton coveralls stand against the walls. Long has a trim goatee and blue eyes that always appear narrowed in concentration, which is a good quality for a man working in a plant that contains enough residual plutonium to build 10 bombs the size of the one that destroyed Nagasaki.

He and four others carefully pull on coveralls, rubber shoe coverings, and surgical gloves. They seal the cuffs and seams with masking tape. Then they check the two cards dangling around their necks. One, which resembles a thick credit card, tallies exposure to gamma radiation. The other is called a PNAD, short for personal nuclear accident dosimeter. It records sudden bursts of neutrons, the kind of radiation released in atomic blasts and nuclear reactor meltdowns. The workers call it the “death chip.”

The Plutonium Finishing Plant at Hanford is one of the most dangerous workplaces in the world. From 1944 to 1989 it produced 74,000 tons of weapons-grade plutonium-239. Nearly two-thirds of all the plutonium in the U.S. military’s nuclear arsenal was refined here, and the plant is highly contaminated with not only plutonium but also byproducts such as hexavalent chromium, made infamous by Erin Brockovich. The Department of Energy (DOE) estimates that over the years some 450 billion gallons of industrial and radiological contaminants were dumped directly into the soil. Some of it was stored, and Hanford’s aging complex of 177 underground tanks contain 53 million gallons of chemicals and radioactive liquids; 67 of the tanks have together leaked more than a million gallons. The DOE recently identified six more tanks that have sprung leaks, further threatening water supplies for millions across the Northwest.

Long is overseeing the plant closure for CH2M Hill, a 30,000-employee global engineering company based in Englewood, Colo. CH2M Hill specializes in projects very few others can manage, from cleaning up nuclear waste sites to widening the Panama Canal. In 2012 it billed some $6.4 billion. Hanford, which is CH2M Hill’s biggest job—about 4 percent of total business—may be the trickiest of all. “Every hazard that you can reasonably think of is present at this facility,” Long says. “Electrical hazards. Chemical hazards. Radioactivity hazards. We’ve got your standard ergonomic hazards. We’ve got industrial hazards. We’re dealing with a small chemical spill right now.”

Many rooms in the plant, which has the appearance and dimensions of a large maximum security prison, contain high levels of airborne radioactive particles, requiring workers to wear respirator hoods and air filters. Some rooms, such as the americium recovery room, are so contaminated, workers can enter them only through portable air locks and connected to air hoses like astronauts exploring another planet. Although americium-241 is highly radioactive, minuscule amounts of it can be found in smoke detectors. In 2004, British authorities arrested an al-Qaeda operative who was planning to make a radiological “dirty bomb” from thousands of the detectors.

The face of the K-East reactor core. The grid in the middle is a series of aluminum tubes that once held uranium fuel rods
Photograph by Steve Featherstone


Long stops in front of a door. Inside this room, he explains, is glovebox HA-23S. Gloveboxes are common in laboratories; they are sealed, usually clear boxes in which technicians handle hazardous material via two gloves attached to holes in the side. But this is not a normal glovebox. It is 16 feet tall, 4 feet wide, and 11 feet long, and was used to store containers of plutonium for 38 years. Built of stainless steel and leaded glass 3/16 of an inch thick, it weighs 10 tons. Hanford, at its peak, used 232 such gloveboxes. There are 55 left to demolish.

HA-23S is the largest and most complex box that Long’s decontamination and demolition teams have tackled so far. Workers have spent 18 months cleaning it, painting it, splitting it in half, wrapping the pieces in plastic, and finally, hoisting the pieces onto a trolley. From there, HA-23S will be put in a special container and shipped off-site to be cut up and buried. “We had zero contamination release and nothing on the knives we used to cut the plastic,” Long says. “It took a little time to do that, and it cost a little money, but the results are undeniable.”

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