Design flaws may have led to San Onofre plant shutdown, NRC says
Federal regulators believe that the unusual equipment problems that have shuttered San Onofre for more than four months stem from a design issue.
U.S. Nuclear Regulatory Commission spokeswoman Lara Uselding said preliminary findings of an NRC probe at the plant suggest that design problems, rather than the way the equipment was put together or installed, led to the issues.
The plant has been out of service since a steam generator tube sprung a small leak Jan. 31, leading to the discovery of unusual wear on numerous tubes in the plant's newly replaced steam generators. The new steam generators had been operating for less than two years when the issues arose.
NRC Regional Administrator Elmo Collins told the Associated Press on Sunday that the wear appeared to stem from design flaws but the report did not discuss what the design issues may have been. Uselding had no further details on what aspect of the design might have caused the problems.
NRC staff will present their initial findings in more detail at a meeting Monday night in San Juan Capistrano.
An environmental group, Friends of the Earth, filed a legal petition with the NRC on Monday asking the agency to launch a full license amendment process, including a trial-like public hearing, to review the design changes in the new steam generators.
Arnie Gundersen, a consultant for Friends of the Earth, has argued that Edison did not report all of the significant design changes to the NRC and that the NRC allowed the steam generator replacement to go through a streamlined review when it should have gotten more extensive scrutiny.
Edison has maintained that it was open with the NRC about the changes.
-- Abby Sewell
Photo: San Onofre nuclear power plant. Credit: Allen J. Schaben / Los Angeles Times