Richard Clarke, who has led the division for the past 11 years, is being replaced -- a nationwide search is underway to find a successor.
The PUC's executive director describes the San Bruno explosion as a game changer.
The explosion last September destroyed 38 homes and eight people were killed.
Since then, the PUC has doubled the number of inspectors, formed a new risk assessment unit, and stepped up the testing and replacement of aging pipes.
