Use and Shutdown
Clementine operated successfully from 1946 until 1950 when the reactor was shut down to correct a problem with the control and shim rods. During this shut down it was noted that one of the natural uranium rods had ruptured. It was replaced and the reactor was restarted.
It was again operated successfully until 1952 when the cladding on one of the fuel rods ruptured. This caused contamination of the primary cooling loop with plutonium and other fission products. At this time it was decided that all the primary objectives of Clementine had been achieved and the reactor was permanently shut down and dismantled.
Read more about this topic: Clementine (nuclear Reactor)