Beef up security at nuclear waste storage sites like San Onofre, scientist says

When San Onofre Nuclear Generating Station was splitting atoms, it had to play — and win — a high-stakes game.

“Force-on-force” exercises — i.e., simulated terrorist attacks on nuclear power plants, pitting a mock adversary force against a plant’s security force — are required for operating commercial reactors by the U.S. Nuclear Regulatory Commission. Back in the day, San O operator Southern California Edison sought to repel pretend intruders and stave off pretend nuclear sabotage, while the NRC took notes on what might be tweaked to improve safety.

Now, however, San O’s reactors are in pieces. They powered down for the last time more than a decade ago. Edison no longer holds a license to operate a nuclear power plant, but rather, to host high-level nuclear waste in dry storage until the federal government figures out where to put it permanently. This waste decays in steel containers encased in concrete; the potential for mischief is much reduced; and those force-on-force exercises are no longer required.

Which leaves some with a queasy feeling in the gut. In recent years, that included staffers at the NRC itself. They began drafting new rules to beef up security at the ever-growing number of “stranded” nuclear waste sites like San Onofre — then stopped, concluding that all is fine as is.

This, the Union of Concerned Scientists argues, ignores the serious issues raised as to why a new approach to spent fuel security was considered in the first place.

The San Onofre Nuclear Generating Station  in 2019. (File Photo by Leonard Ortiz, Orange County Register/SCNG)

“Putting aside the regulatory legalese, what would you want security to accomplish? To prevent an attacker from doing something that would lead to a significant amount of damage to the fuel and a radiological release that would harm the public and damage property and agriculture,” said Edwin S. Lyman, director of Nuclear Power Safety with the Union of Concerned Scientists.

“There’s no alternative but to make sure that attackers cannot credibly accomplish that, and that would, given all the uncertainties, mean there should be a security force to prevent attackers from getting anywhere near the fuel.”

Edison has an armed, 24/7 security presence, officials said, but neither the current regulatory framework nor the staff recommendations — which will be considered soon — requires that. And an armed response force doesn’t have to be able to interdict and neutralize attackers — it only has to detect them and call for help, Lyman said.

And there’s no NRC force-on-force exercise to test it.

Complicating matters, at least in Lyman’s eyes, is Edison’s request to the NRC to shrink the “controlled area boundary” around San Onofre’s dry waste storage area. The NRC’s rules require 100 meters of space around waste storage, but the physical realities of the bluff and the beach make that impossible. Instead, San Onofre’s boundary would be smaller — just 38 meters on the seaward side, beyond which is a publicly accessible pedestrian walkway and the beach itself.

San Onofre Nuclear Generating Station (Photo by Paul Bersebach, Orange County Register/SCNG)

NRC staff recommend approving that request, which Lyman also finds disturbing.

“Rather than concluding you should shrink the controlled area boundary, you might be concerned about the level of public access that’s already there,” he said. “Reading between the lines, this would allow Edison to have no legal responsibility for what goes on in that strip of beach.”

Call 911!

Decommissioning sites like San Onofre “currently implement a ‘detect, assess, and communicate’ protective strategy (as opposed to a “denial of task” protective strategy),” the NRC staff report says.  A successful response “is only to detect and assess the threat and then communicate with (law enforcement) to request assistance, rather than to respond to the attack by interdicting and neutralizing the threat.”

On-site officials essentially call 911, which could happen in less than a minute after an adversary penetrated the protected area’s intrusion detection system, if it wasn’t detected before then. “Neutralization” of the adversary is the responsibility of law enforcement, not of Edison.

Requiring more security was on the table in recent years, but staff now feels that the risks at waste storage sites are so low that costs would exceed the benefit.

There were attempts to calculate radiation dosage thresholds in accident scenarios, but that proved technically problematic. “There are no design basis accidents with offsite dose consequences exceeding” ‘current legal limits, and “dose consequences” will decrease over time as the fuel decays, the report said. (T)he potential impacts from accidents … would not be significant.”

To provide assurance that a terrorist attack would not lead to a significant radiological event, the NRC evaluates the threat environment in coordination with intelligence and law enforcement, requires “protective measures … to reduce the chance of an attack that leads to a significant release of radiation,” and licenses only robust storage casks that resist penetration.

“Over the past 25 years, there have been no known or suspected attempts to sabotage, or to steal, radioactive material from storage casks at (dry storage sites), or to directly attack one,” the report says. “Nevertheless, NRC is continually evaluating the threat environment to determine whether any specific threat …exists.”

Key security features include physical barriers, surveillance, intrusion detection, intrusion response and offsite assistance from local law enforcement agencies. At San Onofre, there are increased security patrols, augmented security forces and weapons, additional security posts, heightened coordination with local law enforcement and military authorities, enhanced screening of personnel and additional limitations on vehicular access.

“Collectively, these measures further reduce the already low probability of a successful terrorist attack … by providing assurance that an attempted attack could be detected and by mitigating the extent of damage and the potential radiological consequences if an attack were successful,” the NRC says.

“Plausible threat scenarios” include a large aircraft impact similar to 9/11 as well as ground assaults, which would not pose significant threats, the NRC says. But it acknowledges the unknowns.

“Because of the uncertainty inherent in assessing the likelihood of a terrorist attack and the unlimited number of potential scenarios, the NRC recognizes that under general credible threat conditions, although the probability of such an attack is believed to be low, it cannot be reliably quantified,” it says. “The NRC has adopted an approach that focuses on ensuring that the safety and security requirements are adequate and effective in countering and mitigating the effects of terrorist attacks against storage casks. …The NRC finds this protective strategy reduces the risk from a terrorist attack to an acceptable level.”

A surfer at San Onofre State Beach. (File photo, Mark Rightmire, ORANGE COUNTY REGISTER/SCNG)

Approving a smaller controlled boundary at San Onofre “would have no change to the consequences of a hypothetical terrorist attack as compared to the current state,” the NRC said. “Public access to the beach and areas up to the security fence is currently allowed. A potential release from a hypothetical terrorist attack will be immediate and of limited duration. Changing the (boundary) will have no effect on the size or position of the release. …

“In conclusion, the probability of a significant radioactive release caused by a terrorist attack remains very low, and the potential health and land contamination effects of the most severe plausible attack would not be altered by the proposed (boundary) as compared to the existing (boundary). If a terrorist act did occur, it would not reasonably be expected to result in a significant release affecting the public.”

Not enough?

Edison concurs with the NRC’s analyses that current security measures do the job, as well as the staff recommendation that San O’s boundary be adjusted to reflect the geography it sits on.

“Edison supports the NRC’s conclusions based on nearly two decades of research, analysis, and testing that (dry storage systems) are safe, and it is not necessary to continue to pursue the revised security requirements that were originally proposed in 2007,” spokeswoman Liese Mosher said by email.

And the proposed exemption to the boundary distance “is an acknowledgment of the facts,” she said. “Importantly, the exemption basis is representative of the very low dose rates that the (dry storage system) provides – dose rates so low at the new boundary line that they are not measurable above background (e.g. the same radiation dose that is in your own backyard).

“Also, during any accident scenarios, which is highly improbable but nevertheless evaluated, the result was that the calculated accident dose was shown to be well within federal limits.”

The response by local law enforcement and other agencies during an accident remains unchanged, she said. Edison’s emergency director would suggest “protective action” to law enforcement, and law enforcement would decide what to do.

The NRC, for its part, directed us back to its staff reports for a response to Lyman’s critiques.

“The staff finds that the existing security requirements … together with the additional requirements in the post-9/11 security orders, provide reasonable assurance of adequate protection of public health and safety regardless of the (dry waste storage) license type or location,” it said. “Staff experience shows that the staff, licensees, applicants, and other stakeholders have been able to understand and apply the existing … security requirements, and the staff has successfully addressed the appropriate security considerations for new license applicants on a case-by-case basis.”

Rotors that have been cut up and sit in a pile at the San Onofre Nuclear Generating Station in Camp Pendleton, CA, on Thursday, December 16, 2021. (Photo by Jeff Gritchen, Orange County Register/SCNG)

Proposed changes in decommissioning rules could increase the clarity and consistency of how to comply, a spokesman said. And the environmental assessment it issued on the San O boundary request explains that the change would not increase the risk of an accident or hostile action resulting in a dose to the public above regulatory limits. A decision on that request should be coming soon.

Lyman doesn’t think that’s enough.

“The NRC does not require that Edison or any other (dry waste storage) licensee maintain an armed response force responsible for interdicting and neutralizing attackers, but only for detecting intruders and calling for help from local law enforcement,” he said. “I do not think that security posture is adequate, especially with public access permitted so close to the spent fuel casks.

“Any capabilities that Edison may claim beyond NRC’s minimal requirements are strictly voluntary, uninspectable, unverifiable, and unenforceable. I believe that NRC’s regulatory footprint must be expanded for all (dry waste storage sites), including San Onofre, which is why I still strongly support a new (dry waste storage) security rulemaking.”

The Holtec Hi-Storm Umax dry storage system for spent fuel at San Onofre Nuclear Generating Station. (Courtesy Southern California Edison)

A terrorist attack could be much more serious than officials are willing to acknowledge. And while the NRC concentrates on doses to humans under threat scenarios, Lyman worries about the impact on property and agriculture.

A shield, he pointed out, is apparently being set up over waste storage at Ukraine’s Zaporizhzhia nuclear plant, to protect it from shelling and drones. That’s the sort of thinking Lyman would like to see here.

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