Senior Advisor for Environmental Management David Huizenga speaks during an event announcing the completion of work to place N Reactor in safe storage.
An aerial photo shows the N Reactor complex just before work to place the reactor in safe storage, or "cocooning," was completed.
Nearly half a century later, David Huizenga, Senior Advisor for Environmental Management, took part in an event to announce that the Richland Operations Office and DOE contractor Washington Closure Hanford completed placing N Reactor in interim safe storage.
“N Reactor stands as a symbol of what we can achieve with large-scale cleanup at Hanford,” Huizenga told a crowd of about 100 invited guests and workers attending the event this month. “Congratulations to each and every worker for their significant role in contributing to N Reactor and Hanford cleanup.”
Placing a reactor in interim safe storage is a process also known as “cocooning.” Hanford’s reactors are scheduled to remain cocooned for up to 75 years to allow DOE, regulators and stakeholders to determine the final disposal method and to allow the structures’ high radiation levels to decay to safer levels.
“Completing the cocooning process is the culmination of years of detailed planning and safe, disciplined operations by workers dedicated to protecting one another, the environment and the river,” said Carol Johnson, Washington Closure Hanford president.
Hanford’s reactors produced the plutonium needed for atomic weapons associated with America’s defense program during World War II and throughout the Cold War. N Reactor operated from 1963 to 1987, making it the longest running reactor at Hanford. It was the last of Hanford’s nine reactors to be shut down and the sixth to be cocooned.
N Reactor was the only dual-purpose reactor in the United States, producing plutonium for the nation’s nuclear weapons program and steam for electricity. At its peak, the 860-megawatt reactor generated enough power for about 650,000 homes.
Huizenga, speaking near the site where Kennedy addressed a crowd of 37,000, repeated the president’s words that day: “Along this river, men have played a significant role in the last 20 years, which has changed the entire history of the world.” The president also spoke of “the role that the men and women who work here have played in the years since the second World War in maintaining the strength of the United States.”
Huizenga said, “The current workers of the Hanford nuclear reservation are carrying on that legacy.”
The reactor building was 85,450 square feet and included three below-grade floor areas (47 feet deep), and four floors above grade level — the highest point is 80 feet tall. The cocooning process also involved isolating the Heat Exchange Facility, an adjacent structure that contained the steam generators for producing electricity.
During the $65 million cocooning project, the reactor building was demolished down to its concrete shield walls surrounding the reactor core. All equipment was removed and all loose contamination within the facility was stabilized. Temperature and moisture sensors were then installed for remote monitoring, the roof was constructed and all openings were sealed.
After the Chernobyl accident in 1986, N Reactor was shut down for routine maintenance, refueling, and safety upgrades because of perceived similarities to the Soviet reactor. Although the upgrades were completed, the reactor never operated again. It was decommissioned when the Cold War ended in 1989, marking the beginning of the cleanup era at Hanford.
Washington Closure manages the $2.3 billion River Corridor Closure Project for DOE’s Richland Operations Office. The River Corridor is a 220-square-mile section of the Hanford site and borders the Columbia River. It is DOE’s largest environmental cleanup closure project.