X-10 Graphite Reactor X-10 Graphite Reactor The X-10 Graphite Reactor at Oak Ridge National Laboratory in Oak Ridge, Tennessee, formerly known as the Clinton Pile and X-10 Pile, was the world's second artificial nuclear reactor (after Enrico Fermi's Chicago Pile-1), and the first designed and built for continuous operation. It was built during World War II as part of the Manhattan Project. While Chicago Pile-1 demonstrated the feasibility of nuclear reactors, the Manhattan Project's goal of producing enough plutonium for atomic bombs required reactors a thousand times as powerful, along with facilities to chemically separate the plutonium bred in the reactors from uranium
Marshall Holloway as a laboratory instrument to test critical mass calculations and the effect of various tamper materials. The Water Boiler group was headed by Donald W. Kerst from the University of Illinois, and the group designed and built the Water Boiler, which achieved its criticality in May 1944 under the control of Enrico Fermi, after one final addition of uranium enriched to 14% uranium 235. It was world third reactor but the first reactor to use enriched uranium as a fuel, using most of the world's supply at the time, and the first to use liquid nuclear fuel in the form