The 100 K Area at Hanford is starting to look a little bare.
Where once 85 buildings stood around the K East and K West Reactors, just 25 remain.
The K East Reactor still looms as a gray monolith just 400 yards from the Columbia River. But its size is deceptive.
After work to tear the reactor down to the shield walls around the reactor core, it has less than half the footprint of its nearby twin, the K West Reactor.
"Our strategy is to take out the facilities not necessary to support the reactor," said Tom Teynor, Department of Energy project director. "Then we will go after the soil sites."
The K East and K West Reactors are the last of the plutonium-production reactors lining the Columbia River that will be cocooned, or put in storage for 75 years while their radioactivity decays to more manageable levels.
Six of the nine reactors already have been cocooned and the first reactor to be built, B Reactor, will be saved as a museum.
The K Reactors have been left until last because their attached cooling basins were used to store irradiated fuel that was not processed to remove plutonium for the nation's weapons program. The fuel, left unprocessed after the Cold War ended, decayed and created a highly radioactive sludge.
With sludge from both reactor basins now moved to underwater containers at the K West Reactor basin, work has begun to cocoon the K East Reactor.
The offices, ventilation room and outer control rod room of the K East Reactor have been torn down. Inside what remains of the reactor, work is continuing to remove lead, asbestos, mercury and oils from pumps so the reactor can be put in storage.
In addition, metal plates and concrete are being used to seal up openings in what remains of the reactor.
Then, in a new method of cocooning for the site, a steel shell will go around it, topped with an angled roof to direct rain water runoff away from adjacent soil waste sites.
Work has been under way for years to clean out and tear down the research and support buildings around the two reactors, but it ramped up significantly with the help of federal economic stimulus money in 2009 and continues with money from the annual Hanford budget.
One of the biggest changes is the tear down of huge water systems with a combined size of more than 1 million square feet of concrete buildings and basins to provide cooling water for each reactor.
Each system was large enough to supply enough water for the city of New Orleans, said Mike Swartz, deputy project manager for deactivation and demolition at CH2M Hill Plateau Remediation Co.
Last week the last of the 40-foot-high tunnel that brought up to 140,000 gallons a minute of water to the K East sedimentation basin was being knocked down by CH2M Hill.
Already the K West water system is down and not much remains of the K East system besides concrete that will be buried in place and used as fill there.
The water systems were built of thick, heavily reinforced concrete to withstand a 2,000-pound bomb during the Cold War.
Some of the concrete rubble, including from the K West system's 292,344-square-foot sedimentation basin, will be used for fill at the U Canyon, a huge processing plant that will have its walls collapsed and topped with an earthen cover.
Trucks make a loop, taking concrete rubble to U Canyon and then bringing back the clean dirt excavated in the expansion of the Environmental Restoration Disposal Facility, a central Hanford landfill, to be used as additional fill material near the K Reactors.
Boaters along the Columbia River are seeing a change along the shoreline near the reactors. Pump houses for both reactors have come down after berms were built and riprap added to protect the river and water quality during demolition.
Environmental cleanup of the K Reactors area has been a priority because it is so close to the river, Teynor said.
Some of the cleanup work being done now is required to meet a legal deadline in December to have some of the buildings gone and waste sites cleaned up, said Rod Lobos, an engineer for the Environmental Protection Agency, a Hanford regulator.
But some other buildings will need to remain to support the K West Reactor until the radioactive sludge it now stores is removed to central Hanford so the basin can be drained and the reactor cocooned. Construction is being done on an annex needed to load out the bulk of the sludge from the basin.
-- Annette Cary: 582-1533; firstname.lastname@example.org