The San Onofre Nuclear Generating Station [SONGS] has been having a hard time since buying some very badly designed replacement steam generators for its two units from Mitsubishi Heavy Industries in 2010 and 2011. Turned out stress and metal fatigue in the interior tubing makes the steam generators unable to handle the job they were designed to do. Unit 3 was shut down in 2011 due to a radiation leak caused by steam tube failure, and will be out of service for the foreseeable future. Southern California Edison [SCE] has been trying to talk the NRC into allowing them to restart unit 2 at 70% power so it can use up the fuel currently in its core, despite the fact that so many of its damaged SG tubes have been plugged that the facility would be in violation of regulations without a special exemption.
Now ABC 10 News in San Diego reported last week that an anonymous engineer is blowing the whistle on restart, saying it would be far too dangerous with the damaged steam generators.
"There is something grossly wrong," said the inside source, a safety engineer who worked at San Onofre and has 25 years in the nuclear field.
The source, who requested anonymity due to concerns about his own safety, has some support from ex-NRC employee, Dr. Joe Hopenfeld. Hopenfeld spent his entire professional life working with steam generators in the nuclear industry, and says the MHI steam generators suffer fatal design flaws.
"The manufacturer didn't have experience in this size unit," said Hopenfeld. "I have reviewed thousands of pages of assessment and reports that Edison has submitted."
San Onofre has been shut down since a 2011 radiation leak coming from tube failures inside the steam generators. The leak revealed a "potentially catastrophic" problem, say the whistleblower and Hopenfeld, which could lead to a major steam line break that could cause the core to overheat and lead to a full or partial
meltdown. The anonymous safety engineer said the San Onofre emergency plan is not geared to handle such an accident, nor have plant personnel or first responders ever practiced for such an event. Nearly 8.5 million people live within 50 miles of the facility, and the city of Los Angeles is just 60 miles up the road.
In a pressurized water reactor like the ones at San Onofre, primary coolant water is heated by the core to about 600 ºF [315 ºC] under ~2,250 pounds per square inch pressure. This water flows through the interior tubes of the steam generators, where the heat is transferred to a secondary water loop to become steam. That steam is used to turn the turbine and generate electricity, then is condensed and returned to the steam generators to be turned into steam all over again. When SG tubes fail the radioactive reactor coolant water mixes with the steam feedwater loop and contaminates the generation machinery and building outside the containment, releasing radioactivity to the environment. This is precisely what happened at San Onofre unit 3 in 2011 and revealed the extent of the tube damage in the steam generators at both units.
California Senator Barbara Boxer blasted SCE and the NRC earlier this month for hurrying the unit 2 restart. Boxer has called for a full investigation into the structural flaws that plague the new steam generators.
"The NRC staff proposal, which could pave the way for the restart of the San Onofre nuclear power plant before the investigation of the crippled plant are completed, is dangerous and premature," Boxer said in a statement [...] "It makes absolutely no sense to even consider taking any steps to reopen San Onofre until these investigations look at every aspect of reopening the plant, given the failure of the tubes that carry radioactive water."
Massachusetts representative Ed Markey joined Boxer in sending a letter to the agency urging the NRC to complete its investigation before allowing restart of unit 2. SCE and the NRC are looking for a June 1 restart date, though there is considerable opposition from area citizens to that plan. In March of last year Irvine Councilman Larry Agran called for the plant to be decommissioned as soon as possible. More than 4,000 tons of radioactive waste (primarily spent fuel) is stored at the plant as well, which will remain there no matter what happens with the reactors because there is still no safe place to put it. Many in Southern California believe that's enough, and are not anxious to accumulate more right there on the beach, in a seismically active area.
In fact, San Onofre was designed to handle a 7.0 earthquake, but sits near faults now known to be capable of 8.0 and above. The 9.0 earthquake off the coast of northern Japan in March of 2011 was only about a 6.5 at Fukushima, where it and the subsequent tsunami caused as many as 6 total core meltdowns and 4 huge hydrogen explosions, releasing more radioactive contaminates than the 1986 disaster at Chernobyl. The probability of a major quake in Southern California within the next 30 years is 60%. It doesn't take a psychic to see that this facility is a disaster waiting to happen and should be decommissioned. Losing Southern California to a Fukushima-like dead zone can be prevented, but not if the people who should know better decide to play Russian Roulette.