SCE is disappointed that MHI decided on its own to redact some information in its evaluation about the flaws in the computer codes. However, the NRC publicly disclosed the computer code flaws three months before MHI completed its evaluation. In addition, the corrective actions and other statements included in the evaluation make it evident that there were problems with the computer modeling that failed to predict conditions that led to the tube-to-tube wear.SCE has proposed operating Unit 2 at 70 percent to decrease velocity and decrease steam dryness to increase damping, thus preventing the conditions that led to excessive wear. The proposed restart plan was validated using a different computer model and has been reviewed by independent experts. The San Onofre nuclear plant is the largest source of baseload generation and voltage support in the region and is a critical asset in meeting California’s summer electricity and clean energy needs. Both units at San Onofre are currently safely shut down. Unit 2 remains shut down since it was taken out of service Jan. 9, 2012, for a planned outage. Unit 3 was safely taken offline Jan. 31, 2012, after station operators detected a leak in a steam generator tube. NRC approval is required before SCE can restart Unit 2. The repair, corrective action and restart plan for Unit 2, along with additional technical information to address questions from the NRC, are available to the public at www.SONGScommunity.com More information, including videos that explain how a steam generator works and the role San Onofre plays in providing reliable electricity to the region, is available at www.edison.com/SONGSupdate and at www.SONGScommunity.com. San Onofre is jointly owned by SCE (78.21 percent), San Diego Gas & Electric (20 percent) and the city of Riverside (1.79 percent). Follow us on Twitter ( www.twitter.com/SCE) and like us on Facebook ( www.facebook.com/SCE). About Southern California Edison An Edison International (NYSE:EIX) company, Southern California Edison is one of the nation’s largest electric utilities, serving a population of nearly 14 million via 4.9 million customer accounts in a 50,000-square-mile service area within Central, Coastal and Southern California.
1 MHI Root Cause Analysis, page 41: T/H condition “was judged acceptable by FIV analysis" and "T/H analysis (FIT-III) did not indicate the necessity to reduce the high steam quality (void fraction)."