N-Reactor
Encyclopedia
Neutron moderator
In nuclear engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, thereby turning them into thermal neutrons capable of sustaining a nuclear chain reaction involving uranium-235....
nuclear reactor
Nuclear reactor
A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid , which runs through turbines that power either ship's...
constructed during the Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...
and operated by the U.S.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
government at the Hanford Site
Hanford Site
The Hanford Site is a mostly decommissioned nuclear production complex on the Columbia River in the U.S. state of Washington, operated by the United States federal government. The site has been known by many names, including Hanford Works, Hanford Engineer Works or HEW, Hanford Nuclear Reservation...
in Washington.
It was a one-of-a-kind design in the U.S., being both a power reactor used to feed the civilian electrical power grid via the Washington Public Power Supply System
Energy Northwest
Energy Northwest is a United States public power joint operating agency formed by State law in 1957 to produce at-cost power for Northwest utilities. Headquartered in Richland, Washington, the WPPSS became commonly knowns as "Whoops"before being renamed Energy Northwest in November 1998...
(WPPSS), and a plutonium
Plutonium
Plutonium is a transuranic radioactive chemical element with the chemical symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, forming a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation...
production reactor for nuclear weapon
Nuclear weapon
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter. The first fission bomb test released the same amount...
s.
N-Reactor was built with a confinement building instead of a containment building
Containment building
A containment building, in its most common usage, is a steel or reinforced concrete structure enclosing a nuclear reactor. It is designed, in any emergency, to contain the escape of radiation to a maximum pressure in the range of 60 to 200 psi...
. In the event of an accidental release of steam, air and steam would vent through filters that confined any radioactive particles present. It was partially moderated with graphite, but had a negative void coefficient, meaning it was thermally stable.
The reactor was placed on cold standby in 1988, with "final disposition" beginning in 1994.