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Arco, Idaho

Arco, Idaho

"Electricity was first generated here from Atomic Energy on December 20, 1951. On December 21, 1951, all of the electrical power in this building was supplied from Atomic Energy."

Those words are written on the wall of a nuclear reactor in Arco, Idaho, a site now designated as a Registered National Historic Landmark by the U.S. Department of the Interior . The inscription is signed by 16 scientists and engineers responsible for this event.

The production of electricity from nuclear power was truly a momentous occasion. Scientists had known for nearly two decades that such a conversion was possible. Use of nuclear energy as a safe, efficient energy source of power was regarded by many people in the United States and around the world as one of the most exciting prospects for the "world of tomorrow."

Until 1945, scientists' efforts had been devoted to the production of nuclear weapons . The conclusion of World War II allowed both scientists and government officials to turn their attention to more productive applications of nuclear energy. In 1949, the United States Atomic Energy Commission (AEC) authorized construction of the first nuclear reactor designed for the production of electricity. The reactor was designated Experimental Breeder Reactor No. 1 (EBR-I).

The site chosen for the construction of EBR-I was a small town in southern Idaho named Arco. Founded in the late 1870s, the town had never grown very large. Its population in 1949 was 780. What attracted the AEC to Arco was the 400,000 acres (162,000 ha) of lava-rock-covered wasteland around the town. The area provided the seclusion that seemed appropriate for an experimental nuclear reactor. In addition, AEC scientists considered the possibility that the porous lava around Arco would be an ideal place in which to dump wastes from the reactor.

On December 21, 1951, the Arco reactor went into operation. Energy from a uranium core about the size of a football generated enough electricity to light four 200-watt light bulbs. The next day its output was increased to a level where it ran all electrical systems in EBR-I. In July 1953, EBR-I reached another milestone. Measurements showed that breeding was actually taking place within the reactor. The dream of a generation had become a reality.

The success of EBR-I convinced the AEC to expand its breeder experiments. In 1961, a much larger version of the original plant, Experimental Breeder Reactor No. 2 (EBR-II) was also built near Arco on a site now designated as the Idaho National Engineering Laboratory of the U.S. Department of Energy . EBR-II produced its first electrical power in August of 1964.

[David E. Newton ]



"A Village Wakes Up." Life (9 May 1949): 98101.

Crawford, M. "Third Strike for Idaho Reactor." Science 251 (18 January 1991): 263.

Elmer-DeWitt, P. "Nuclear Power Plots a Comeback." Time 133 (2 January 1989): 41.

Schneider, K. "Idaho Says No." The New York Times Magazine 139 (11 March 1990): 50.

U.S. Congress, Office of Technology Assessment. The Containment of Underground Nuclear Explosions. OTA-ISC-414. Washington, DC: U.S. Government Printing Office, 1989.

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