They remain blind to the truth of human error.
Once a nuclear accident happens, it is too late.
NO MORE NUCLEAR VICTIMS
Coffee House Teach Ins
San Luis Obispo Mothers for Peace [http://mothersforpeace.org] / (805) 773-3881 / P.O. Box 3608 San Luis Obispo, CA 93403
PROTEST against Diablo and stand up for clean energy.
Join at a peaceful demonstration on Saturday, April 16.
Meet at Avila Pier in Avila Beach, CA, at noon.
Bring signs and the messages that:
* We can no longer ignore the warnings from Fukushima Daiichi, Chernobyl, and Three Mile Island
* Diablo Canyon is on shaky ground; the area is riddled with over a dozen earthquake faults
* Nuclear Energy is not worth the risk to our lives and our planet
* Stop the license renewal process at Diablo
2011-03-18 "Diablo Canyon nuclear plant 'near miss' in report" by David R. Baker from "San Francisco Chronicle" newspaper
[http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2011/03/17/BUA01IDTUO.DTL&tsp=1]
Bloomberg News contributed to this report.
For 18 months, operators at the Diablo Canyon nuclear plant near San Luis Obispo didn't realize that a system to pump water into one of their reactors during an emergency wasn't working.
It had been accidentally disabled by the plant's own engineers, according to a report issued Thursday on the safety of nuclear reactors in the United States.
The report, from the Union of Concerned Scientists watchdog group, lists 14 recent "near misses" - instances in which serious problems at a plant required federal regulators to respond.
The report criticizes both plant operators and the Nuclear Regulatory Commission for allowing some known safety issues to fester.
"The severe accidents at Three Mile Island in 1979 and Chernobyl in 1986 occurred when a handful of known problems - aggravated by a few worker miscues - transformed fairly routine events into catastrophes," the report notes.
The problem
The problem at Diablo Canyon, which is owned by Pacific Gas and Electric Co., involved a series of valves that allow water to pour into one of the plant's two reactors during emergencies, keeping the reactor from overheating.
The loss of water in a reactor can lead to at least a partial meltdown - a process believed to be under way at Japan's stricken Fukushima Dai-ichi nuclear plant after last week's earthquake and tsunami.
Engineers at Diablo Canyon inadvertently created the problem while trying to solve another issue, according to the report.
A pair of remotely operated valves in the emergency cooling system was taking too long to move from completely closed to completely open. So engineers shortened the distance between those two positions, according to the report.
Unfortunately, two other pairs of valves were interlocked with the first. They couldn't open at all until the first pair opened all the way. No one noticed until the valves refused to open during a test in October 2009, 18 months after the engineers made the changes.
"It was disabled, and they didn't know it," said Jane Swanson, spokeswoman for the Mothers for Peace anti-nuclear group, which frequently spars with federal regulators over Diablo Canyon. "That's unforgivable, and it's not that unusual."
In an emergency, Diablo Canyon operators still could have opened the valves manually.
They could also have used a separate system of pumps to inject water into the reactor, PG&E spokesman Kory Raftery said.
"We want to make sure we put safety first - that's why we have redundant systems," he said.
He added, "The potential is very small for the type of situation where we'd need this system in the first place."
PG&E has asked the Nuclear Regulatory Commission to extend the licenses of Diablo Canyon's twin reactors past their original expiration dates of 2024 and 2025. Mothers for Peace has opposed that move.
The valve problem and the union's report, Swanson said, illustrate how even minor technical issues at a plant have the potential to cause serious problems.
'Domino effect'
"Any given nuclear power plant is such a complex system," she said. "As we've seen in Japan, the domino effect can happen."
With the Japanese crisis riveting world attention, Sens. Barbara Boxer and Dianne Feinstein called on the Nuclear Regulatory Commission on Wednesday to perform thorough safety inspections at Diablo Canyon as well as California's other commercial nuclear plant, San Onofre, in San Diego County.
But the commission's chairman said Thursday there was no immediate need to inspect any U.S. nuclear plants.
Later Thursday, President Obama said the United States faces no danger of radioactive contamination from Japan's nuclear plant and has ordered a comprehensive review of safety at U.S. plants.
2011-03-16 "NEW FAULT DISCOVERED NEAR DIABLO CANYON" by David Perlman from "San Francisco Chronicle" newspaper
An unknown seismic fault has been detected on the ocean floor a half-mile from Pacific Gas & Electric Co.'s Diablo Canyon nuclear power plant, and a company report on the discovery says the plant could safely withstand a magnitude- 6.5 earthquake on the fault.
The fault zone was detected more than two years ago by scientists at the U.S. Geological Survey working with the utility, and was promptly reported to the federal Nuclear Regulatory Commission, but its existence did not become widely known until Tuesday.
William Ellsworth, the USGS scientist who developed the method used to determine the fault's dimensions, said it is "not a major fault." The Shoreline Fault Zone runs for 14 miles offshore in three segments, roughly from the vicinity of a coastal feature called Point Buchon northwest of the plant to well out in San Luis Obispo Bay.
Ellsworth said the USGS and the utility have long had a standard cooperative agreement to work jointly on seismic research, and that the fault was found by scientists gathering seafloor data for a new assessment of probabilities for major quakes in the Bay Area.
The fault, Ellsworth said, runs vertically about 6 miles beneath the seafloor and is known as a "strike-slip" fault, which means that in its motion one side would slip past the other.
The fault lies about 3 miles inshore from the well-known Hosgri Fault, whose discovery in 1971 by scientists forced PG&E to upgrade the plant's design.
California's ecology was nearly DESTROYED
Below photographs show the Diablo Canyon nuclear power plant:
2011-03-18 "Nuclear safety: Five recent 'near miss' incidents at US nuclear power plants" from "Christian Science Monitor" newspaper
[http://www.csmonitor.com/USA/2011/0318/Nuclear-safety-Five-recent-near-miss-incidents-at-US-nuclear-power-plants/Diablo-Canyon-California-Emergency-systems-disabled]
Fourteen safety-related events at nuclear power plants required follow-up inspections from the Nuclear Regulatory Commission, the NRC reported in 2010. These "near-miss" events "raised the risk of damage to the reactor core – and thus to the safety of workers and the public," concluded a new report, "The NRC and Nuclear Power Plant Safety in 2010," by the Union of Concerned Scientists. Here are five of these 14 "near miss" examples:
1. Diablo Canyon, California – Emergency systems disabled
At the Diablo Canyon nuclear plant, operators found themselves unable to open the valves that provide emergency cooling water to the reactor core and containment vessel, during a test on October 22, 2009.
A misguided fix of an earlier problem had prevented the emergency valves from opening, the NRC team sent to investigate found.
Tests after the valve repairs had failed to detect the problem, meaning that the reactor had operated for nearly 18 months with vital emergency systems disabled. Although the earlier modification impaired the emergency core cooling systems, workers could have opened the valves manually, which reduced the severity of the violation, the report said.
2. Wolf Creek, Kansas – Emergency system leaks
Seven hours after the Aug. 19, 2009 automatic shutdown of the Wolf Creek nuclear plant, due to an electric problem related to a lightning strike, an NRC inspector found water leaking from the system that cools the emergency diesel generators and virtually all other emergency equipment.
An internal study in 2007 had forecast such leakage, showing that a vital cooling system was prone to rust damage that would result in leaks. Management did nothing, the UCS report says. In 2008, the same piping developed the leaks, just as predicted. Management only patched the leaks, doing little about the rusting causing the problem. In 2009, the piping developed more leaks. This time, workers failed to notice the water puddling on the floor until an NRC inspector found it 7 hours later.
(While the event occurred in 2009, the NRC report appeared in 2010.)
3. Brunswick, North Carolina – Delayed reactor time
At the Brunswick nuclear plant, Halon gas – a fire suppression agent – was mistakenly discharged into the basement of the building housing the emergency diesel generator, on June 6, 2010. The release of the toxic gas into a vital area prompted control room operators to declare an alert – the third-most-serious emergency classification.
Workers did not know how to notify emergency responders, the NRC team discovered, so it took 2-1/2 hours to fully staff and activate onsite emergency response facilities – twice as long as specified in the plant’s emergency response procedures.
Fortunately, the incident was not an actual emergency, the report author notes.
4. Fort Calhoun Nuclear Plant, Nebraska – Failure of emergency equipment
On Feb. 17, 2010, the NRC sent a team to the nuclear plant after the turbine-driven auxiliary feedwater (AFW) pump automatically shut down shortly after operators started the pump during a monthly test.
The AFW system is an emergency system that remains in standby mode during normal plant operation. However, although the AFW system plays a vital role in an accident, the NRC investigators found that the pump had failed numerous times over many years. The owner had never found the cause of the problem, and therefore had never taken steps to prevent it.
The NRC identified four violations of its safety regulations.
5. Surry Nuclear Plant, Virginia – Failure to recognize a problem
Degraded electrical equipment caught fire in the control room of Unit 1, about 90 minutes after an electrical short led to an inadvertent shutdown of the reactor, on June 8, 2010.
Six months earlier, a fire had broken out in the Unit 2 control room – because of similarly degraded electrical components.
After putting out the Unit 2 fire in November 2009, workers had asked technicians to investigate, but the company closed the report without any investigation or evaluation.
After the second fire, workers tested electrical components in both control rooms and found many were degraded, including some that produced visible sparks during testing.
Because the company had taken no action to protect Unit 1 from the problem they had been warned of in Unit 2, NRC's investigation team sanctioned the company.
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