The San Onofre nuclear power plant returned its Unit 2 reactor to service this week, concluding a 43-day routine shutdown for refueling and maintenance, Southern California Edison said. Operators at the plant started the reactor Tuesday, and it was running yesterday at 37 percent of power, said plant spokesman Ray Golden. The reactor was expected to reach full power by Saturday, but it could be operating at capacity as early as today, he said. Edison hired 1,400 contract workers, supplementing its own work force of 1,800, to perform numerous maintenance jobs during this latest shutdown. Among them was a detailed...