INL Media Release
June 3, 2015

Laura Scheele, 219-381-8672,
Misty Benjamin, 208 351-9900,

Idaho National Laboratory mourns the passing of Leonard Koch

IDAHO FALLS – Idaho National Laboratory today recognized the passing of nuclear pioneer Leonard Koch at the age of 95. The American Nuclear Society announced his passing in a June 1 news posting.

“The visionary work of Leonard Koch and his colleagues lives on today as the world moves toward advanced nuclear reactor designs to meet global energy needs,” said John Grossenbacher, INL Lab Director. “They proved essential principles of nuclear energy here in Idaho and established the basis for the advanced energy research that continues at INL today.”

Koch was a pioneer in the development of the original concept of nuclear power and was a leading world expert on fast reactor technology. He was the associate project engineer for Argonne National Laboratory working on the Experimental Breeder Reactor-I at the National Reactor Testing Station in Idaho in 1951 during EBR-I’s first successful run, which proved that nuclear power could be used to produce electricity.

Koch, who later became project manager for development of a successor reactor, the EBR-II, called his times working on the EBR programs his “happy days in this business.” His research proved to be a fundamental blueprint for the construction of nuclear plants globally.

In just 12 years of operation, EBR-I achieved many firsts: the first reactor to generate usable quantities of electricity from atomic energy, the first breeder reactor, the first to use liquid-metal as a coolant, and the first plutonium-fueled reactor. While EBR-I successfully demonstrated the feasibility of breeder reactors–or reactors that could breed more fuel than they consumed–EBR-II showed that reactor and fuel recycle systems were scalable to a full-scale power station. During the first few years of its operation, EBR-II recycled the core through the reactor five times, demonstrating the feasibility of a closed fuel cycle.

EBR-I was dedicated as a Registered National Historic Landmark on Aug. 25, 1966, by President Lyndon Johnson and Glenn Seaborg, chairman of the Atomic Energy Commission. The facility is now a museum open to the public for tours throughout the summer season.

INL is one of the DOE’s national laboratories. The laboratory performs work in each of DOE’s strategic goal areas: energy, national security, science and environment. INL is the nation’s leading center for nuclear energy research and development. Day-to-day management and operation of the laboratory is the responsibility of Battelle Energy Alliance.

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In the video produced by Argonne National Laboratory below, Leonard Koch discusses his work at EBR-I and EBR-II.