Skip to main content

Why Diablo Canyon is Safe from Earthquakes

This morning in a conference call with nuclear energy bloggers, NRC Chairman Allison Macfarlane, in response to a direct question about the safety of the Diablo Canyon Power Plant, said "[We] believe the plant is safe ... Otherwise it still wouldn't be operating." For the why behind that conclusion, you ought to review two reports that were released yesterday afternoon.

On Wednesday, PG&E released a report confirming the seismic safety of Diablo Canyon Power Plant. The report, the Central Coastal California Seismic Imaging Project, is 14 chapters long, but the bottom line is delivered succinctly by The Tribune, the paper of record in San Luis Obispo.

The report will now be peer reviewed by an NRC committee that includes Neal Driscoll, a professor of geology and geophysics at the Scripps Institution of Oceanography in San Diego. When asked about the report after its release yesterday ...
[Driscoll] said PG&E marshaled many state-of-the-art tools for the study to better understand the faults around Diablo Canyon and reduce uncertainty. He looks forward to analyzing the study.

“I think releasing these reports to the public so that they can be vetted and peer-reviewed is a great step forward,” he said.
Back in Washington there was more good news about Diablo Canyon, as NRC once again concluded that there were "no immediate seismic safety issues at the plant." That report was issued in response to concerns raised by the plant's former resident inspector. As was reported in The Tribune this morning:
Mark Satorius, the NRC’s executive director for operations, on Wednesday issued a response to the safety issues raised by Peck in an appeal that he filed with the agency. That appeal criticized a 2009 review of the safety implications of the Shoreline Fault that runs just offshore of the plant.

Peck filed the appeal, called a differing professional opinion, in July 2013. The agency convened an independent review panel to look at his allegations, and Satorius met with Peck to hear his concerns. His response is in the form of a memo to Peck.

“A compelling basis for my conclusion is drawn from our meeting on July 30, 2014, when you and I agreed that there is not now nor has there been an immediate or significant safety concern associated with this Diablo Canyon issue,” Satorius said in his response to Peck.
For more information on the plant and its operations, visit its website.


Vinod Arora said…
Diablo Canyon Power Plant

To alleviate public concern & confusion, PG&E needs to explain clearly in Meetings with the Public, Critics, NRC ASLB, NRC ACRS and others “Based on the latest seismic studies, seismic retrofits and the past, ongoing and continuous equipment seismic qualification/surveillance/testing/inspections programs, PG&E concludes, ‘All the Diablo Canyon Power Plant safety related and important to safety structures, systems and components will perform their safety/engineering function to shut down the reactor and mitigate the consequences of the largest earthquake/ground vibratory motion caused by POTENTIAL ocean/ground seismic activities within 200 miles of DCPP. PG& E is in compliance with all the current NRC and ASME regulations. Public safety is overriding obligation of PG&E. PG& E meets the NRC Reasonable Assurance Criteria and Public Safety Commitments through excellence in operations, maintenance and regulatory compliance.”’
Vinod Arora said…
San Onofre Replacement Generators
All the steam generators should operate with void fractions less than 98%, fluid velocities less than 20 feet/second and circulation ratios greater than 4 to prevent the adverse effects on tubes & tube support systems of in-Plane FEI & fluid induced random vibrations. It is MHI’s Myth and Misleading Statement that MHI can design AVBs & tube support systems in high flow steam generators to avoid adverse effects on tubes & tube support systems of in-Plane FEI & fluid induced random vibrations in a dry steam environment (void fractions 99.6-100%). This statement is supported by review of discussions of Dr. Pettigrew, Westinghouse & AREVA with NRC Commissioners. Industrial & Academic Benchmarking and rejection by NRC/SCE of MHI Repair Plans for San Onofre Replacement Steam Generators.
Rochelle Becker said…
The same attributes which have earned PG&E the distinction of being America’s only nuclear licensee facing criminal prosecution from the U.S. Department of Justice—including a leading charge of obstruction of justice—extend to the company’s conduct of the AB 1632 seismic studies.
What the Alliance For Nuclear Responsibility (A4NR) filing demonstrates is PG&E’s attempt to subvert the oversight of a state sanctioned independent review panel, which PG&E successfully dodged with a trumpeted submittal of its “final” seismic study to the NRC before the peer review panel had even been shown the results. Notes A4NR attorney John Geesman, “Without independent review, this report is propaganda, not science.”
AB 1632, sponsored by then Assembly Member Dr. Sam Blakeslee, mandated updated studies to determine if new hazards in the seismic setting of the Diablo Canyon nuclear plant posed a risk that could impact the cost and reliability of the electric supply. In 2012, the CPUC authorized $64M in ratepayer funds for PG&E to do the study. At the same time, admitting that the CPUC had no internal staff to determine the validity of the study and its results, the CPUC established an Independent Peer Review Panel (IPRP) comprised of members including the California Geologic Survey, Coastal Commission, Energy Commission, Seismic Safety Commission, County of San Luis Obispo, and others...see website

Popular posts from this blog

A Design Team Pictures the Future of Nuclear Energy

For more than 100 years, the shape and location of human settlements has been defined in large part by energy and water. Cities grew up near natural resources like hydropower, and near water for agricultural, industrial and household use.

So what would the world look like with a new generation of small nuclear reactors that could provide abundant, clean energy for electricity, water pumping and desalination and industrial processes?

Hard to say with precision, but Third Way, the non-partisan think tank, asked the design team at the Washington, D.C. office of Gensler & Associates, an architecture and interior design firm that specializes in sustainable projects like a complex that houses the NFL’s Dallas Cowboys. The talented designers saw a blooming desert and a cozy arctic village, an old urban mill re-purposed as an energy producer, a data center that integrates solar panels on its sprawling flat roofs, a naval base and a humming transit hub.

In the converted mill, high temperat…

New Home for Our Blog: Join Us on

On February 27, NEI launched the new We overhauled the public site, framing all of our content around the National Nuclear Energy Strategy.

So, what's changed?

Our top priority was to put you, the user, first. Now you can quickly get the information you need. You'll enjoy visiting the site with its intuitive navigation, social media integration and compelling and shareable visuals. We've added a feature called Nuclear Now, which showcases the latest industry news and resources like fact sheets and reports. It's one of the first sections you'll see on our home page and it can be accessed anywhere throughout the site by clicking on the atom symbol in the top right corner of the page.
Most importantly for you, our loyal NEI Nuclear Notes readers, is that we've migrated the blog to the new site. Moving forward, all blog posts will be published in the News section, along with our press releases, Nuclear Energy Overview stories and more. Just look for the &qu…

Hurricane Harvey Couldn't Stop the South Texas Project

As Hurricane Harvey battered southeast Texas over the past week, the devastation and loss of life in its wake have kept our attention and been a cause of grief.

Through the tragedy, many stories of heroics and sacrifice have emerged. Among those who have sacrificed are nearly 250 workers who have been hunkered down at the South Texas Project (STP) nuclear plant in Matagorda County, Texas.

STP’s priorities were always the safety of their employees and the communities they serve. We are proud that STP continued to operate at full power throughout the storm. It is a true testament to the reliability and resiliency of not only the operators but of our industry.

The world is starting to notice what a feat it is to have maintained operations through the catastrophic event. Forbes’ Rod Adams did an excellent job describing the contribution of these men and women:

“STP storm crew members deserve to be proud of the work that they are doing. Their families should take comfort in the fact that…