Good morning. I’m Allen Camp, manager of the risk assessment and systems modeling department at Sandia National Laboratories. I’m going to talk to you this morning about nuclear reactor surety. In the past we have dealt with all aspects of surety, including security; however, today I’ll be focusing on the safety and reliability aspects of surety.

1. Overview

Referring back to previous discussions describing the levels of surety, we consider nuclear reactors to be at approximately the 3^rd level, that is, they rely on redundant automatic safety systems to ensure safety. In some cases positive operator intervention is also required, which is more at the second level. Now, we believe our current generation of nuclear power plants to be safe. However, because of the potential hazard and complexity associated with the technology it pays to remain vigilant. Therefore, over the past 25 years, in partnership with the Department of Energy, the Nuclear Regulatory Commission and other National Laboratories, we have developed an integrated approach to reactor safety based on a combination of science, modeling and simulation, and risk management.

2. Integrated Approach (Slide)

We believe that surety for any complex and hazardous system must be based on a fundamental understanding of the technology and any potential accidents that can occur. Hence, we have developed a number of facilities at the national laboratories to study the physics and chemistry of potential reactor accidents. For example, we have the large melt facility to examine molten core phenomena, the Surtsey facility to examine high pressure melt ejection from a vessel, and a number of containment test facilities to examine potential structural failures.

Now these and other facilities have been invaluable in helping us understand how accidents can occur. Unfortunately, we can’t run experiments to consider all possible combinations of events that could occur during a reactor accident. Therefore, we have developed a suite of modeling and simulation tools that we have benchmarked against the experiments. These computer models can then be run over and over to examine large numbers of potential accident sequences. On the left side of the screen you can see an example where we have an experiment for how a reactor vessel fails under a certain condition and right underneath that picture you can see the computer model of that event. Once we have these models we can then run them over and over to look at a wide range of possible accident situations.

Once we have an understanding of how accidents can progress, we can assess the risk to the public and take steps to manage those risks. This risk management has included improved operator training, system modifications, and improved regulatory processes. The integrated approach to reactor safety has been successful because it focuses on issues important to decision-makers and has a sound foundation based on engineering and science.

3. Spinoffs

This approach has not only been successful for nuclear reactor surety, but parts of this technology have been spun off for application in other areas. For many years there has been technology exchange with the nuclear weapons programs. In the 70s and 80s, some of the technology was applied to nuclear waste management and nuclear materials transportation problems. We are now applying some of our advanced risk and reliability analysis techniques to problems of the critical infrastructure where we are solving telecommunications network reliability problems and are examining the safety of commercial aircraft.

4. Future

We believe nuclear energy to be an important part of our nation’s energy future, particularly given problems with greenhouse gases associated with fossil fuels. However, the future of nuclear energy depends not only upon safe designs and public acceptance but also on economic viability. The challenge we're facing right now in the nuclear business is to try to understand how to use the advanced concepts of surety to not only maintain and perhaps enhance safety but also to develop a new generation of plants that are cost effective to construct, operate, maintain and regulate. That challenge will be the subject of our breakout session this afternoon.

Thank You.

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