Massive Hanford test reactor near Richland pulled from ground

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A massive test reactor just north of Richland has been lifted out of the ground in one the most hazardous and complex cleanup projects along the Columbia River at Hanford, according to the contractor doing the work.

The reactor is the largest and last of the six test reactors once used for research at the Hanford 300 Area.

Getting the reactor out took three years of work and planning, including one major setback.

But sometime this weekend, Route 4 South from north of Richland to the Wye Barricade is expected to be closed to traffic as the reactor is hauled on a trailer with 384 wheels to distribute the weight of the 1,538 tons it will be carrying.

"We're going to scream out of here at 1 mile per hour," said Gary Snow, director of decontamination and demolition for Department of Energy contractor Washington Closure Hanford.

The reactor was used in the 1960s to test fuel containing recycled plutonium for possible use in commercial nuclear power reactors.

The reactor and its shielding will be disposed of at the Environmental Restoration Disposal Facility, a lined landfill for low-level radioactive waste in central Hanford.

The 309 Reactor, also called the Plutonium Recycle Test Reactor, was housed below ground under the 80-foot tall gray dome near Richland. Until it was cut off and taken down in 2011, the dome was one of Hanford's most distinctive structures near Richland and featured on postcards of the nuclear reservation.

Originally, Washington Closure Hanford planned to cut away most of the 5-foot thick concrete surrounding the reactor for radiation shielding. Then the 560-ton reactor was to be lifted out of the ground.

But when workers drilled into the concrete shielding, it proved to be too degraded from heat in the areas closest to the reactor for that plan to be practical.

"Every facility we go into has unknown hazards," Snow said.

Instead, Washington Closure and DOE devised a more complex plan to remove just enough of the concrete shielding to allow lifting equipment to be inserted and fitted around it. Then the reactor could be lifted out of the ground with the concrete radiation shielding and steel liner plates used for heat shielding intact.

That brought the weight of the lift to 1,082 tons, or more than 2 million pounds.

Pieces of concrete had to be removed to allow the lifting equipment to be lowered and to provide enough space around the reactor to lift it out of the ground. A crane lifted out concrete chunks weighing up to 10 tons.

More cuts with a wire saw were needed to free the reactor from the floor and walls. Workers also had to remove hundreds of pipes.

Before a frame for the lifting system could be installed, a temporary structure had to be built 32 feet below the ground to receive, move and assemble the lift frame. The reactor sat above the bottom floor of the building. Shoring columns were needed to reinforce the containment structure.

"What made the work hazardous was doing it in confined spaces," said Mark French, DOE project director for the work.

Workers also needed to wear protective clothing and respirators and work in summer heat and the cold of winter.

They also had to be prepared for radioactive contamination.

Work to lift the 1,082 tons straight up, with just inches of clearance, began Tuesday and continued Wednesday.

The lifting was done with four jacks mounted on a 30-foot tall mobile lifting frame. The total weight of the reactor with the lift-frame assembly, which will be hauled with the reactor to unload it at the landfill, is 1,538 tons and it stands 36.5 feet tall.

At the landfill, a 30-inch thick concrete pad has been poured inside a disposal trench and topped with soil where the reactor will be placed. The same jacks used to lift the reactor out of the ground will be used to offload it at the landfill.

Hanford officials will be watching the weather for the planned transport of the reactor this weekend. Conservative regulations for moving the reactor on the road require the temperature to be at least 32 degrees in the unlikely event that cold weather could cause a crack in the reactor if an accident occurred and the reactor fell.

The below-ground concrete structure that housed the reactor still must be removed and that should be completed by fall.

Having the reactor and the structure out of the ground will allow piping and waste sites in the area to be removed in time for much of the cleanup of Hanford along the Columbia River to be completed in late 2015.

"It will free the land up for future use" likely by industry, French said.

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