The Nuclear Regulatory Commission has suggested that Mitsubishi Heavy Industries (TYO: 7011) used the wrong equipment to fix California’s San Onofre nuclear plant.
According to the NRC, Mitusbishi didn’t verify whether tubes being used in a mock-up generator to study potential repairs matched specifications for such tubing in the San Onofre nuclear plant. More than 1,000 such tubes are in question.
The plant has been shut down since January after excessive wear to the tubing, which carries radioactive water, resulted in a tube break and the release of trace amounts of radiation, Insurance Journal reports.
The NRC questioned Southern California Edison’s idea of restarting one of the two shut-down reactors and then running it at low power in an effort to stop the vibrations that have been consistently damaging tubes. Southern California operates the San Onofre plant, and the NRC is due to issue a decision on how the plant should be handled by March of next year.
The real problem appears to be that Mitsubishi was about to use the results from this flawed testing to set up further research, meaning future work could have resulted from these poorly-executed tests.
Federal officials have already targeted Mitsubishi over related issues; apparently, company officials had not judged accurately how water and steam would flow within the nuclear reactors, thus resulting in design flaws that lie at the heart of the tubing wear issues.
While wear is expected in steam generator tubing, the San Onofre generators had been replaced in a $670 million operation and just started operating in April 2010 and February 2011 respectively. The short operating time is why the amount of erosion and wear concerned investigators.