On Monday , January 23 , 1961 , Pacific Gas and Electric held a luncheon to invite the community to observe the start of the major construction of the nuclear unit . Concern about previously undiscovered seismic faults combined with more stringent requirements required after the Three Mile Island accident rendered the small plant unprofitable if restarted . It was shut down for refueling and seismic upgrades in July 1976 , which dragged on due to changing requirements . PG&E announced plans to permanently shutter the plant in 1983 , and it was then placed in SAFSTOR inactive status in 1988
Three Mile Island accident
Three Mile Island accident
Humboldt Bay Nuclear Power Plant