« McCain Finds Lynn's Responses "Disappointing" | Main | We Don't Need Any Additional Plutonium Pits »

Jan 30, 2009


Per Peterson

The problem is not so much with the current Design Basis Threat description. Instead it is with the use of a DBT approach in the first place.

On the safety side, the Three Mile Island accident taught us that the use of a near worst-case Design Basis Accident (large break loss of coolant) for the design of safety systems and training of personnel, instead of focusing the majority of effort on identifying and designing/training for the most likely accidents (e.g., small break loss of coolant accidents).

Terrorists are strategic actors. They select which targets to devote their resources to attack based upon their assessment of the probability that they can succeed and the consequences that they can generate. The most important thing to do is to devote resources to protecting those targets that terrorists are more likely to choose, and as those targets are better protected and terrorists look elsewhere, to protect the next target the terrorist is likely to choose, and so on, applying this approach to allocate defensive resources to both nuclear and non-nuclear targets.

The current DBT causes a very large misallocation of resources. For example, there is a wide range of potential consequences from attacks on different U.S. nuclear plants, but the DBT approach does not require any greater protection for a plant that terrorists would be more likely to target like Oyster Creek (which is near a densely populated area), than one that terrorists would be less likely to target like Palo Verde (which has a very sparse population around it).

Likewise the DBT prescribes the amount of information that terrorists must be assumed to have about a plant. Thus the DBT approach provides no basis to determine whether it is better to invest enhanced personnel reliability programs to reduce the potential access to insider information and assistance, versus more guns and guards.

The DBT provides no basis to determine whether it is more effective to invest in counter terrorism and police capabilities that can identify the signatures generated by terrorist preparations and stop attacks from happening in the first place (against all kinds of targets), versus in attempting to harden all of the targets to resist the attacks.

Likewise the DBT approach provides no basis to optimize between the investment in hardening targets, versus capabilities to mitigate consequences and perform emergency response, which are investments that can also be applied to respond to non-nuclear attacks and to accidents and natural disasters.

In our approach to physical security, we are still living in a pre-TMI world using pre-TMI policies and tools. We learned an enormous amount from the TMI accident that is applicable to improving our approach to security as well. What we really need is new NRC commissioners who will push to fix the current flaws of the DBT approach.


Be careful what you wish for. Many nuclear plants already have a guard force larger and more capable than their county police force. Expanding the DBT will require some utilities to have a larger force than their state national guard. Do you really want a private company with the defacto capability to overthrow the government, and the rate increase that will be needed to pay for it?

We're already paying the government to protect us from military threats. Let them handle it.


President Obama should act right away.
David Lochbaum for Commissioner.

The comments to this entry are closed.