At California Nuclear Plant, Earthquake Response Plan Not Required But the Diablo Canyon nuclear plant, which sits less than a mile from an offshore fault line, was not required to include earthquakes in its emergency response plan as a condition of being granted its license more than a quarter of a century ago. Though experts warned from the beginning that the plant would be vulnerable to an earthquake, asserting 25 years ago that it required an emergency plan as a condition of its license, the Nuclear Regulatory Commission fought against making such a provision mandatory as it allowed the facility to be built. Officials at Pacific Gas and Electric Company, the utility that operates Diablo Canyon, did not respond to calls seeking comment before the story was published. After publication, a spokesman for the company said the plant does have an earthquake procedure that had been implemented during a 2003 earthquake near the facility, and that staff are trained to respond. The company did not provide further details upon request.