Nils Diaz: The level of safety in reactors is a continuous improvement that has really been remarkable, especially the last 10 to 15 years...the reality is that nuclear power plants in this country and abroad are operated at a much higher level of safety than what they were.

If you look at our reports to Congress for the past many, many years, the only real issues were the large amounts of radiation were either given to a person as an internal or external radiation event, really comes from the medical and from the industrial communities.

We used to be a safety agency. We just always did public health and safety, public health and safety. Well, 9/11 changed that completely. We are now a safety, security and preparedness agency. We are no longer one-dimensional. These three areas, safety, security, and preparedness are being integrated in a synergistic manner so each one reinforces each other.

We actually increased the security for access control, security for protection against ground, a land-based attack. We issued new water-based criteria, and we required the licensees to actually be prepared to deal with the potential effects of an aircraft attack. And out of that came a continuing study which is called our Aircraft Vulnerability Study. The studies, as you know, are classified but they do confirm that the power reactor facilities are the most protected civilian facilities in the country…. a defense-in-depth [approach] gives us time to deal with unexpected events no matter where they come from.

What we have learned in the last two and a half years is a sophisticated set of analyses that I believe have ever been done on power reactors is that we have time, and time is on our side. And therefore, we have concluded that the potential radiological consequences from aircraft attacks on nuclear power reactors are low.

Q&A:
Q : Last week before Senator Voinovich’s hearing, he took a little bit of heat from a GAO report regarding the Davis-Besse incident. There was some discussion. Part of the issue was safety culture and whether NRC should be involved in the safety culture. Have you considered your position or the agency’s position, that that really doesn’t fall under your jurisdiction, or do you think you’re likely to?

Diaz: There is no doubt that the NRC is committed to a strong safety culture in our licensees, but the way we do it, rather than just saying have a safety culture, we have a series of indicators. We require our licensees to have a strong safety culture. That somebody once in a while doesn’t do it, there’s no doubt about it, and it happens. It happens here, it happens everywhere.

We require it [First Energy Corp.] for five years provide independent assessment of their culture, their operations. We have only done that—we did a little bit with Milstone when we required them to provide an independent body to look at their culture, and an independent assessment of their safety system. So in unique cases, we do it. We’d rather the licensees do it, and see what the results are.

Q: Well, the GAO report mentioned the possibility for other mishaps is still out there. You mentioned that First Energy’s safety culture obviously wasn’t good. Are you concerned that there are other ticking time bombs out there that could come up if you don’t look at it more closely.

Diaz: I can categorically tell you that there’s never going to be another hole in the head of a reactor vessel in this country. I mean, you’re never going to find one. Fundamentally if you look at what it cost them, there is no other industry in this country that’s going to take that risk.

A year ago I started to push very hard and established a materials degradation program. At the same time then, the industry has established major programs in Materials Degradation. This, by the way, is not an issue only of the nuclear power industry. This is an issue of America, do we have many, many assets that have materials degradation problems, and we need to come up with a new technology, a new way of fixing them.

Q: Chairman, you’re a nuclear engineer by training and a nuclear professor before you joined the NRC. Do you feel that the need for technology is evolving or is it frozen in time? We haven’t seen a new plant, since everybody knows in more than 30 years. In everything else we see technological evolution, oil (inaudible) is something different after 30 years than it was before. How do you feel about the evolution of technology?

Diaz: I believe that for the nuclear power industry to move forward they need to evolve more rapidly. They need to actually have plans that run more efficiently, at little higher temperatures. There are many, many things that are state-of-the-art, and they are bringing them in into the old plants. But if there are new power plants, they definitely need to move into an area that makes them more efficient, and at the same time, we will require them to be moving at a higher level of safety; meaning that inherent safety becomes part of the criteria, rather than something that you add on later on.

Q: If the agency has three, maybe four years to get through this very complex [Yucca Mountain] license application, even in the best of times, is this a job that the NRC could get done in that period of time, or do you think it’s going to take longer?

Diaz: How long do I have to answer this question? No, fundamentally three years is very tough. It’s very, very difficult for us to handle this massive adjudicatory process, which is going to probably be the largest that as ever been done in this country in a three year period, but we’re going to try. We’re going to give it our best try…if it’s a very good application and it’s delivered on time, we’re going to try our best to do it in three years, but we will do it in four years.

Q : Mr. Chairman, you mentioned a moment ago that most over-used word in Washington, but that a paradigm of realistic conservatism and at meetings I’ve seen the staff on technical issues this is beginning to be considered and brought into technical meetings on various issues. Can you tell us more about how you hope, and how management is going to make sure that this approach is brought into NRC’s technical analyses and decisions on a more nuts and bolts level with what I think Commissioner McGaffigan referred to as several layers of bounding conservatism studies, how it causes the agency to look to make conservatism in its technical studies more realistic without eliminating important parameters in the study?

Diaz: The issue of realistic conservatism, of course, came out very clearly when we started to deal with some of the vulnerability assessments and some of the consequence analysis. People used to think that conservatisms are good. My point is that unnecessary conservatism is paid [for by] the American people. They pay for it. Everybody pays for the medical procedures, so are we having the American people pay for unnecessary conservatism? And the answer is yes. So what we are doing is from the beginning, we want people to add just the amount of conservatism that they can justify because of the end use, the amount of conservatism that can be assessed.

Q: Can I ask you about the resources at NRC. We’ve had movement and talk about maybe somebody building a natural uranium Canadian CANDU reactor. A while back there was talk about a pebble bed reactor, and you have just talked about a high temperature light water reactor, I think. Do you have any resources to license any new designs?

Diaz: We have made preparations to license what is on our plate. To go beyond that, the answer is no, but we are fully manned to complete the licensing for the AP1000, which final design approval is expected for September. We have two other pre-applications which include the ESBWR and the Advanced CANDU 700.

Q: You talked a bit about the possibility of a plane flown into a nuclear power plant. What’s the worst case scenario if a plane gets a direct hit on a spent fuel pool and you talked about time. How much time?

Diaz: Well, enough time to do all of the things that we need to do to protect the people. Spent fuel pools are okay. There is really very low probabilities of any significant hazards to the public from a direct hit on the spent fuel pool. It’s just really not there…What can I tell you that there is enough time to protect the people around this plant and the people of this country. And that we know.

Q: What’s the technical basis, that it’s just that it’s hard for them to actually catch fire, hard to imagine a leak of the water?

Diaz: Nuclear power reactors don’t have mechanisms for quick releases of radioactivity. They’re just not there. What we have found is that the way that these plants were built, operated, and what we call the severe accident and mitigation strategies that were put in these power plants in the late 1980s, early 1990s, are very good at mitigating whatever can happen, whether it’s a plane crash or somebody throws a bomb. The combination of these systems are so robust that even if worst case things happen, we have plenty of time to protect the people of this country.

So what I’m saying flat out is that there are no quick mechanisms for significant releases of radioactivity that we have identified. Does that mean that the probability is zero? No. I can’t say that, but it is very low. It means we have analyzed every angle that is most probable, every structure, every system. We have looked at every type of airplane. We have looked at different ways of doing it, and we are convinced enough for me to stand here and to tell the Congress of the United States that the probability of a significant radioactive release to occur before the time that we have protected the people is very low. And that includes not only nuclear power plants, it includes all the spent fuel pools, the independent spent fuel pools at facilities, it includes dry casks and it includes transportation of the spent fuel. Beyond transportation, the transportation casks that we have analyzed. And in those cases, there is either little release, no release, very little release, but in all cases there is time to protect the American people. And that’s the answer that we needed, that’s the answer that we have. And that’s what we are clearly coming out and saying.

Q: You seem to be pretty confident about airborne attacks. How about shipborne attacks. What are you doing about that aspect?

Diaz: Again, we have run the scenarios of water-based attack since February of 2002. Our licensees have had to consider the potential for a water-based attack. They are prepared. They’re ready.

Some people in the industry claim that I am very, very, very—too safety conscious. I’m always pushing them a little bit beyond where they should be. And maybe so. But I do believe that we’re now at a stage where the licensees have responded. They have submitted their plans. We have inspected them, and we know where they are. And, therefore, we’re confident they’re capable of handling the vast majority of what could be thrown at them.