Station blackout rule implementation at Dresden and Quad Cities

The station blackout rule, 10CFR50.63, was issued in 1988 and required all licensees to show adequate capability to cope with a loss of all alternating-current (ac) power. This presentation discusses Commonwealth Edison's approach to demonstrating compliance with the rule at the Dresden and Quad Cities stations. The Dresden and Quad Cities nuclear stations were completed in the early 1970s and have similar designs. Each of the stations has two General Electric boiling water reactor units. The emergency ac power sources at each station consist of three diesel generators; one diesel generator is dedicated to each unit, while the third is a shared swing diesel