Oak Ridge National Laboratory was completed, later renamed to "Oak Ridge National Laboratory". The site was chosen for the X-10 Graphite Reactor, used to show that plutonium can be created from enriched uranium. Enrico Fermi and his colleagues developed the world's second self-sustaining nuclear reactor after Fermi's previous experiment, the Chicago Pile-1. The X-10 was the first reactor designed for continuous operation. After the end of World War II the demand for weapons-grade plutonium fell and the reactor and the laboratory's 1000 employees were no longer involved in nuclear weapons. Instead, it was used for scientific research. In 1946 the first medical isotopes were
National Atomic Energy Commission reactor was built (1957), the RA-1 Enrico Fermi. The 335-MWe Atucha I designed by Germany's (Siemens) was completed in 1974. In 1984 the 600-MWe Embalse designed by Canadian CANDU started its commercial operation. In 1995 CNEA's functions where divided into newly created separate organizations such as the Nuclear Regulatory Authority ("Autoridad Regulatoria Nuclear - ARN"), which supervises nuclear safety in the country, and the "Nucleoeléctrica Argentina - NASA", the company that operates the two completed nuclear power reactors. Today, CNEA mainly focuses on research and development of nuclear and related technologies. In 2001 the original 1956 Directory structure of a