Unit 1 was designed for a peak ground acceleration of 0.18 g ( 1.74 m\/s2 ) and a response spectrum based on the 1952 Kern County earthquake , but rated for 0.498 g . The design basis for Units 3 and 6 were 0.45 g ( 4.41 m\/s2 ) and 0.46 g ( 4.48 m\/s2 ) respectively .
Unit 1 was designed for a earthquake peak ground acceleration shaking motion of 0.18 g ( 1.74 m\/s2 ) and a seismic response spectrum based on the 1952 Kern County earthquake .