Diablo Canyon, California’s last nuclear power plant, can safely withstand earthquakes, tsunamis and flooding that could potentially occur in the region according to a new report released March 9, 2015 by PG&E. Evaluations were performed at the direction of the Nuclear Regulatory Commission (NRC).
As part of its response to the Fukushima event in Japan in 2011, the NRC directed all U.S. commercial nuclear power plants to perform a reassessment of the potential seismic and flooding hazards to their facilities. The seismic hazard analysis at Diablo Canyon was performed using an NRC-mandated process known as the Senior Seismic Hazard Analysis Committee, or SSHAC. Under the SSHAC process, existing and new seismic information was peer-reviewed and publicly evaluated by third-party, independent seismic experts.
The NRC will review the seismic re-evaluation in order to provide guidance on how and when PG&E should perform an additional risk evaluation that examines the probability of earthquakes potentially damaging plant safety equipment. The new analyses, known as hazard re-evaluations, will be submitted to the NRC this week for independent review.
The analysis includes data acquired during the advanced seismic studies recently performed near Diablo Canyon, to re-evaluate how earthquakes could potentially impact the facility. This process included examining the probability of earthquakes occurring on individual and multiple geologic faults.
“The updated seismic source model for Diablo Canyon incorporates an extensive body of new onshore and offshore data and emerging new scientific concepts to characterize earthquake sources. For example, it is the first earthquake model developed for a nuclear site that allows for multi-fault linked ruptures to produce large maximum earthquakes. Through the extensive use of experts in the field of seismic geology and independent peer review, the model was developed to capture the full range of possibilities regarding the location, size and frequency of large magnitude earthquakes in the vicinity of Diablo Canyon. In my opinion, the model developed for Diablo Canyon will set the standard for how future earthquake source models are developed,” said Bill Lettis, who serves as one the key technical leads for the SSHAC process.
PG&E’s flooding and tsunami hazard update involved the use of the latest NRC guidance and methodologies to determine the maximum potential waves and rainfall that could impact Diablo Canyon.
“These important updates provide an in depth look at the seismic, tsunami and flooding hazards in our region, and most importantly, demonstrate the plant’s design is safe. Our work in these areas, however, will never cease. Our commitment to safe operations and protecting public health and safety will continue to be reflected in our ongoing study and evaluation of the areas. Our customers expect no less,” said PG&E’s Halpin.
Opposition to Diablo Canyon started before it was constructed, by Friends of the Earth (FOE), a political action group founded by activist David Brower in 1969, over concerns about earthquake safety. Brower, who was against nuclear power in general, split with the Sierra Club over the Club’s position on the Diablo Canyon Power Plant. The Club helped block PG&E’s plan for a nuclear power plant at Bodega Bay over concerns of the earthquake danger from the nearby San Andreas Fault, not out of opposition to nuclear power itself. The Club’s board of directors had voted to support the Diablo Canyon site for the power plant in exchange for PG&E’s moving its site. In 1967, a membership referendum upheld the board’s policy. Brower believed that nuclear power was a dangerous mistake at any location, and opposed Diablo Canyon, in defiance of the Club’s official policy. (Wikipedia)
According to FOE, knowledge of earthquakes and faults near Diablo Canyon was insufficient at the time of construction. There have been expensive studies over the last 45 years expanding current knowledge of the seismic risks, new faults, and engineering evaluations and improvement. All studies to date have confirmed the safety of the plant. The current review by third party independent experts evaluated the safety during extreme events on multiple faults, however FOE have not updated their beliefs.
Friends of the Earth has stayed firm in their ideology, and have not shifted their position on seismic safety with respect to new knowledge and testing since 1969, but instead have expanded their opposition to include environmental concerns about Diablo Canyon cooling water, and the cost of electricity. Their ideology is based on perceived risk and threats to the environment, and they oppose fossil fuels, nuclear power, hydroelectric dams, and biofuels in general. FOE states on their website that “Friends of the Earth promotes conservation and clean energy — including wind, solar and geothermal power — and why we fight to end our unhealthy dependence on dirty sources including coal, oil, nuclear and biofuels.”
The ideological labeling from political groups like FOE, prevent them from focusing on actual environmental problems such as greenhouse gases and climate change as issues. Prejudiced ideologic opposition to a label, such as nuclear power or biofuel, does not solve any environmental problem with those topics, and assumes that problems can never be solved. Ideologic positioning closes the door to science, new data and knowledge such as the case of Diablo Canyon with negative consequences for all of us.
FOE’s strategy of creating opposition to nuclear power seems to rely on creating fear about a lable, attracting support from extremist groups such Occupy SF that tend to enlist supporters with fear based statements that reinforce their ideology such as stating on their sites that,
“Diablo is surrounded by some 13 earthquake faults. The plant was designed in the 1960s and won’t withstand a major earthquake. Diablo doesn’t have cooling towers; instead, it uses “once through cooling” using 2/5 billion gallons of ocean water a day to cool the plant and returning that water to the ocean 20% hotter and full of tritium, killing billions of sea creatures. There is no place to put the radioactive waste.”
These claims stretch the truth just a little. Diablo canyon is not surrounded by 13 active earthquake faults, it is designed to withstand major seismic activity on multiple faults at once and has substantial engineering upgrades since the 1960s, and most importantly there is no radioactivity in its cooling water. Extremist groups depend on the lack of real knowledge of the issue by a sector of the public to garner support with such claims. For example, FOE and other extremist groups cite a dissenting paper about Diablo Canyon from a former inspector claiming,
“The NRC’s chief resident inspector at Diablo, Dr. Michael Peck, recommended LAST YEAR to shut the plant because critical backup safety systems aren’t working.”
However, Peck’s analysis rather concludes that no one at the time of him writing it knew if the facility’s key equipment could withstand strong shaking from faults based on new information since the time of construction. It did not presume the plant was unsafe, only that it was unknown and required further testing, which has now been done. These groups have not retracted any of their claims.
Recently, Californians for Green Nuclear Power (CGNP), a local citizens group, has rallied to the support of Diablo Canyon.
“I was frustrated by all the false information put out about nuclear power, I knew it wasn’t true.” stated CGNP founder Bill Gloege as reported by the Lompoc Record.
CGNP gathered in February for the first ever rally in support of Diablo Canyon.
Nuclear power may have issues, but to assume they can never be solved based on ideology, is wrong headed and eliminates a potential solution that would help mitigate climate change, the most important environmental issue of our time.