Pacific Gas and Electric Co. (PG&E) both declared and ended an Unusual Event at the 2,300 MW Diablo Canyon nuclear power plant on Oct. 21 in response to a 5.3 magnitude earthquake near King City, Calif. The earthquake was felt in the control room of the two-unit plant, but there was no impact to operations and both units continued generating power.
Plant operators and engineers performed inspections or “walk-downs” of the site following the Unusual Event declaration. These assessments confirmed there were no impacts to plant equipment or operations, PG&E said.
The Unusual Event declaration followed protocols set by the Nuclear Regulatory Commission (NRC), which also included notification of state and community partners. Such an event is declared for an other-than-normal plant related condition that does not require any emergency action by the general public or any government authorities. It is the lowest of four emergency classifications established by the NRC.
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