An explosion rattled windows across nearby neighborhoods. Orange columns of flame shot like blowtorches out of stacks and pipes, uncontrolled. The incident that shook Chevron’s El Segundo refinery last week once would have prompted a federal investigation. Not anymore. As the Trump administration moves to weaken the U.S. Chemical Safety Board, California still hasn’t said whether any agency, department or authority will take charge of a comprehensive investigation when a refinery erupts —