Issues for NRC meeting in SLO on June 24

This NRC meeting is at Embassy Suites, San Luis Obispo, CA 6 pm - 9 pm. The NRC will be reviewing the operations record for Diablo Canyon during the year 2014.


PG&E’s failure to properly load dry casks with spent fuel assemblies:

  • For the past 15 years or so, PG&E has been using high-burnup fuel – fuel that burns longer in the reactor, and so is much hotter (both in temperature and radioactivity) than the “traditional” nuclear fuel.
  • The higher heat load caused by improperly loading fuel into dry casks has the potential to lead to temperatures higher than the casks can withstand. Cask lids might warp because of uneven temperature distribution inside the cask.
  • This condition would present a danger of oxygen permeating a cask. If oxygen were to hit the zircaloy cladding on the fuel rods, it would spontaneously ignite, causing an uncontrolled release of radiation.
  • Questions: How did this occur? Who was responsible for the cask loading configuration? Who actually loaded the casks? When was the first cask improperly loaded? Did they need to get a license amendment to change the configuration? Why was the configuration changed? Was a rationale given? Who is ultimately responsible?
  • Since PG&E has shown that its “safety culture” is incapable of assuring adherence to technical specifications for the handling of deadly spent fuel, San Luis Obispo Mothers for Peace calls for strict measures to be put in place:
  • Add additional NRC oversight in the form of two additional inspectors at Diablo Canyon nuclear power plant for at least the next two years.
  • Conduct a thorough NRC investigation into the root cause of the problem and make public both the methods used in the investigation and the results.
  • Implement immediate inspection of all 34 dry casks to look for cracking, warping and escape of radiation into the environment.
  • Order immediate shutdown of the plant until the problem has been fully and completely corrected.


  • Quote from p. 5 of Sam Blakeslee’s testimony presented to the SENATE COMMITTEE ON ENVIRONMENT AND PUBLIC WORKS, December 4, 2014:

“… in a seeming contradiction, rather than finding that larger or closer faults produce greater shaking and therefore a greater threat, PG&E argues in the Report that ground motion will be lower than the levels previously estimated. In other words, these newly discovered and re-interpreted faults are capable of producing shaking that exceeds the shaking from the Hosgri, yet that shaking threat would be much reduced from prior estimates.

“… The reason the earthquake threat purportedly went down when new faults were discovered is because the utility adopted significant changes to the methodology utilized for converting earthquakes (which occur at the fault) into ground motion (which occurs at the facility). This new methodology, which is less-conservative than the prior methodology, essentially “de-amplifies” the shaking estimated from any given earthquake relative to the prior methodology used during the licensing process.”

  • From NRC Inspection Report September 10 through November 13, 2014, available on NRC website at ML14349A485
    • From 2010 through 2014, PG&E compiled a report titled the “Central Coastal California Seismic Imaging Project” (CCCSIP). Based upon new seismic information contained within the report, PG&E performed a subsequent operability determination evaluation that was completed on August 21, 2014.
    • PG&E recognizes that the Hosgri, Shoreline, Los Osos, and San Luis Bay faults are connected and capable of greater ground motion than summarized in the 2011 Shoreline Report.
    • PG&E continues to apply its new methodology, not yet explained despite requests from the Independent Peer Review Panel, to again draw the conclusion that despite greater ground motion Diablo is capable of surviving.
  • PG&E is ignoring the fact that its licensing basis requires it to prove it can manage a Double Design Earthquake shutdown. PG&E points out that no other nuclear plant has such a requirement. That is because no other nuclear plant has been given an operating license despite being sited within two and a half miles of a known major, active earthquake fault – the Hosgri Fault.

Severe Flooding

  • PG&E's program for protecting against severe flood events ignores its own post-Fukushima study that clearly showed that heavy rainstorms may likely flood critical backup safety equipment. The plant has to have cooling water flowing through it 24 hours a day in order to prevent a meltdown, both in the spent fuel pools and in the reactor itself.
  • If there were a heavy rainstorm that knocked out power that flows into the plant from the 230 KV lines, and then flooding at the plant caused the backup safety equipment to fail, Diablo Canyon could be left in the same situation as Fukushima - a plant without a functional cooling system. We all know what happened when Fukushima was without power for an extended period of time.

Emergency Planning Inadequate

  • Emergency evacuation zones are required by the NRC to extend only 10 miles around nuclear reactors. Since 2012 SLOMFP has advocated that new zones be established from 25-50 miles around reactors for which utilities would have to identify and publicize evacuation routes.
  • Another improvement urged by SLOMFP would require utilities and state and local governments to practice drills that include a natural disaster that either initiates or occurs concurrently to a nuclear meltdown. Currently, utilities do not have to show the capability to conduct an evacuation during a natural disaster - even though, as seen at Fukushima, natural disasters can cause nuclear meltdowns.
  • SLOMFP has also petitioned the NRC to expand the “ingestion pathway zone,” which monitors food, milk and water, from 50 miles to 100 miles around reactors.
  • In the event of a radiation release from the Diablo Canyon nuclear plant, the County Office of Emergency Services plans to advise residents and visitors to either evacuate or “shelter in place”.
    • There are limited roads to provide for transportation away from the Diablo Canyon nuclear plant in the event of a radiation release.
    • As we learned from the Fukushima on-going disaster, “sheltering in place” is not useful if emergency conditions become long-term.


On September 10, 2014, PG&E issued a seismic report in response to a California law that demanded more information on the fault lines that nearly surround Diablo Canyon.

That same day, the NRC formally rejected the Differing Professional Opinion of Dr. Michael Peck, former senior resident inspector at Diablo Canyon, who had argued that the plant should be closed because it is out of compliance with its operating license. Several newly discovered faults nearby, he said, could produce more violent ground motion than Diablo was designed to withstand.

The timing raised suspicions with Mothers for Peace. We accused the commission and PG&E of colluding to release both the report and the rejection of the inspector’s complaint on the same day, generating positive press about Diablo’s safety. PG&E and the commission denied the accusation, with PG&E saying it had shared a draft of the report with the commission no earlier than Sept. 8.

Using public records act requests, the Alliance for Nuclear Responsibility obtained an internal Aug. 24 commission e-mail with the subject line “communications strategy on state report.” But the commission redacted almost everything in the e-mail after the subject line — four pages of largely blank, white space. The top of each page read “draft talking points: state report,” but the contents were withheld.

Economic considerations

  • Continuing to operate Diablo Canyon beyond the current license makes no economic sense. PG&E has skewed a new analysis of energy alternatives to ignore or reject a wide range of renewable energy options available to replace the power generated by Diablo Canyon.
  • The NRC has no justification for renewing PG&E's license in light of the greater environmental impacts of Diablo Canyon and lesser costs of renewables.
  • Given that the California Independent System Operators find that the energy from Diablo is not necessary to the state of California now, Diablo should be shut down within months, not years.

Once Through Cooling

In 2010, California enacted a new policy intended to address the water and marine environmental protection problems posed by the antiquated Once Through Cooling (OTC) systems of power plants up and down the California coast.  Called the Policy on the Use of Coastal and Estuarine Waters for Power Plant Cooling, this mandate required that by 2015, all coastal power plants must have in place replacement cooling systems that conserve water and protect the marine environment.

  • The nuclear industry lobbied to have until 2015 to provide arguments for if and how they could comply with the policy. San Onofre was shut down in 2013, so that leaves only Diablo in question.
  • Unless the State Water Resources Control Board, which oversees OTC policy, accepts a permanent exclusion from the policy to Diablo owner PG&E, the power plant is by law to have cooling towers in place by 2024 (the date at which the first of the two reactors reaches it current license limit).
  • Reasons for enforcing the Policy to stop OTC
    • Diablo Canyon alone is responsible for nearly 80% of coastal power plant OTC ocean withdrawals (Diablo Canyon: 78 Percent of California Coastal Power Plant Once-Through Cooling  Water Withdrawals by  Bill Powers, P.E., November 23, 2013).
    • Diablo Canyon’s antiquated cooling system draws in an estimated 2.5 billion gallons of water per day and discharges that water back into the ocean some 20 degrees F hotter.  In the course of this intake and outflow, it is estimated that annually the reactors’ cooling system sucks in more than a billion fish in early life stages, most of which die. Additionally, more than 700 pounds of adult fish are destroyed every year.
    • Cooling towers could be built on the current site at the parking lot, which would have minimal land impact, and could use salt water, which would make desalination unnecessary. The construction costs would not exceed $ 2 billion.
    • Mesh screens would be ineffective at protecting sea life. (Even Bechtel, consultant to PG&E, admitted mesh screen technology would not significantly decrease the fish kills caused by intake and outflow.
    • Simply put, defense of the OTC policy and the inclusion of Diablo in the adhering to the policy is one of the most important, most effective, and most obvious things that anyone concerned about the marine environment can do in these next few months. PG&E’s Diablo Canyon power plant ought to be treated just like the other coastal power plants, and profits ought not win out over protection of the environment and public health.