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The Future Of Nuclear Energy In The U.S.

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The Future Of Nuclear Energy In The U.S.


The Future Of Nuclear Energy In The U.S.

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  • Transcript


This is FRESH AIR. I'm Terry Gross.

In the wake of the Fukushima nuclear catastrophe, the American nuclear industry is facing questions about the safety of power plants and the storage of spent nuclear fuel, questions we're going to talk about with my guest, Matthew Wald. He's a reporter for the New York Times and has been covering nuclear power since 1979.

Contamination from Fukushima is spreading. The International Atomic Energy Agency is reporting that dangerous levels of the radioactive isotope cesium-137 were found 25 miles from the Fukushima Dai-ichi nuclear power plant. That's more than double the amount of radioactive contamination that the Soviet Union used as an indicator when it recommended abandoning the land surrounding the Chernobyl reactor.

Matthew Wald reports today that tests of milk samples taken last week in Spokane, Washington indicate the presence of radioactive iodine from the nuclear power plant in Japan, but according to the Environmental Protection Agency, the levels are far below those at which action would have to be taken.

I asked Wald if he was concerned about increased radiation levels in the U.S. from Fukushima.

Mr. MATTHEW WALD (New York Times): We live in a radioactive environment. There are various materials around us with varying levels of natural radioactivity. We're going to add slightly to that from this accident. It's not going to mean a whole lot.

In the United States, we have a sort of odd history. There was one occasion during the Cold War when we were blowing up nuclear bombs in Nevada, where a large dose was delivered in Upstate New York because the cloud traveled for about three days and then there was a rainstorm and it washed out.

Japan is too far away from Hawaii, from the continental United States, to get any concentrated dose here. Our understanding of very small doses of radiation is not good. There's a assumption that any amount is bad for you, but there's also a fairly widespread belief in the technical community that if you add an increment that's just a small fraction of natural background, it probably is not going to make any difference.

GROSS: How close are the majority of the reactors in the United States to the reactors in Fukushima?

Mr. WALD: We have a couple dozen that resemble the Fukushima reactor, except that we probably don't have any that are vulnerable to tsunami. The reactor builders and designers, way back in the '60s and '70s, used a variety of strategies to assure safety.

Some doubt has been cast on the model now in Japan, although to be honest, if you had swamped a different model reactor with a tsunami like this, you'd be in for lots of trouble.

The question is: What can we do to reduce our risk not so much of tsunami but of natural attack or malevolent terrorist attack that's beyond what these places were designed for?

And the answer is, the industry says it's already done a substantial amount after September 11th, and the NRC agrees with that, and the NRC says we're going to look again and see what sort of generic preparations we can make for when things get much worse than we ever thought they could.

GROSS: Well, you mentioned the NRC, the Nuclear Regulatory Commission. I think a lot of people wonder: How politicized is the NRC? How industry-controlled is the NRC? Or is it a neutral, scientific, technical group of people?

Mr. WALD: Well, it's clearly a highly technical agency. Outsiders differ. It does not start from the premise that a lot of nuclear critics start from, which is: Oh my God, this is awful, we're all going to die.

It starts from the engineering premise that everything in life has some risk and we can reduce risk by smart engineering, and we have reduced risks that way, and we need additional work every time we discover some phenomena, some catastrophe somewhere in the world, to see what this tells us.

The commission has had some lapses in the past, where it's had blind spots or it's been too deferential to industry. You get a variety of readings about whether that's the case right now.

I do know that they look at Japan very seriously, and literally they won't say: Well, we're okay, we're not going to have big tsunamis. But they will, in fact, draw conclusions when they get a little more information. Right now information is a little contradictory and sketchy.

GROSS: There are reactors in the United States near fault lines and near hurricane zones. Is there confidence that the reactors can withstand earthquakes or hurricanes? I know they're not earthquakes followed tsunamis, but they can still be pretty disruptive.

Mr. WALD: I have to admit I learned some surprising things here. One of them is: Yes, there are fault lines that are near reactors. There's a joke that a reactor is just a device for locating a fault, because if you built a reactor, you're sure to find a fault nearby.

But many, many active seismic zones and earthquakes are not traced to individual faults. The question isn't: Is there a fault? The question is: Is it active and what kind of ground motion can it produce at your plant location?

The NRC thinks it has a good handle on that. There's one instance of a reactor suffering more ground motion than the designers thought it would. It didn't show major damage as a result.

We do have hurricanes all over the East. Andrew smashed right into one in Florida. It showed some damage, but it basically came through with its safety systems intact, and the surrounding neighborhood was destroyed. You don't expect to get through these things without damage.

There are some preparations we have made that would be good for post-hurricane, post-tornado, which is another postulated event, post-earthquake, where we have extra generators that are powered by diesel fuel, extra diesel fuel in hardened storage. We have stocks of pumps and batteries and other crucial materials we could move to a site quickly.

Essentially, though, when you get to the Fukushima Dai-ichi stage, the question is: Are you prepared for things you hadn't predicted? And the answer is: How can you tell? We're certainly prepared for some things we haven't predicted, but tell me what it is we're preparing for.

GROSS: My guest is Matthew Wald, and he's been covering nuclear energy since 1979. He's a reporter for the New York Times.

How old are most of the reactors in the United States? When was the last time a reactor was built?

Mr. WALD: It turns out to be a trick question. The last one that was ordered and not canceled was October of 1973. The Tennessee Valley Authority has two called Watts Bar that it started to build, ran into financial trouble, management trouble, mothballed them for a while, finished off Watts Bar Unit 1 in 1996, which makes it the youngest, and recently decided it's going to finish Watts Bar Unit 2.

We have two sites in the United States where ground has been broken for brand new reactors, one in Georgia, one in South Carolina. Those don't yet have construction licenses, but you can go ahead and dig a foundation. And the idea for those is those would be about five years away.

GROSS: So since the majority were built in 1973 or before, is that technology considered old now and out of date?

Mr. WALD: It's a little bit like airplanes. You can get on an airplane from that era and it's got updated electronics and it's got carefully inspected parts. But yes, it's an old airplane.

The new designs are fundamentally different. Either they have what's called passive safety systems - for example, you need cooling water. You don't want to have to rely on a pump to get the cooling water there. Let's put the cooling water tank on the roof instead of downstairs. So that's an example of a passive system. Or they have more backup safety systems than existing designs.

The NRC and the engineers say, but this gets a little technical, that their chance of a core damage accident is lower by a factor of 10 to 100. You and I are not going to wait around long enough to see whether their chance of meltdown is one in 10,000 years or one in a million years. But that's what the math that the builders and the regulators say shows.

GROSS: So one of the issues being reexamined in American plants is the battery life. So if there is a power outage because of a destructive event like a tsunami or an earthquake or here a hurricane or a tornado, that there's still power to continue the operations and continue, most importantly, cooling the fuel rods. Do I have that right?

Mr. WALD: Right.

GROSS: Right, because if those rods aren't cooled, you're eventually heading toward meltdown and...

Mr. WALD: The fuel - right, the fuel generates heat even when the reactor isn't running, and unless you remove the heat, eventually it'll overheat, and the fuel rods will break open, and you'll get a release of fission products, of atoms that were created when uranium was split. And all of those are radioactive. They're unstable. They want to give off a particle or a ray, and that's bad stuff.

GROSS: Okay, so the plants in the Fukushima complex had eight-hour batteries.

Mr. WALD: Right.

GROSS: Most of the plants in America have four-hour batteries.

Mr. WALD: Correct.

GROSS: Ninety-three of the - was it 111 plants?

Mr. WALD: Hundred and four.

GROSS: Hundred and four plants - 93 have four-hour batteries, and 11 have eight-hour batteries. But the eight-hour batteries weren't enough in Japan, so...

Mr. WALD: Correct. People are now...

GROSS: We have less than not enough.

(Soundbite of laughter)

Mr. WALD: That's correct. Congressman Markey of Massachusetts, a long-time critic of the industry, has a bill he's introducing that would require 72-hour batteries.

I should say that, by the way, the batteries are never enough to run cooling pumps, but they are enough to run valves, which are electrically operated, and these valves are sometimes in places you can't get to in an accident.

They can run instruments that tell you pressures, flow rates, temperature. And some of these reactors have pumps that run on steam, which you tend to have in abundance if you're still producing heat.

So between the control provided by the batteries and the raw power provided by the steam, a longer battery would seem to be one way to insure yourself against really, really prolonged station blackout, loss of offsite power, loss of emergency diesels.

The design philosophy in the United States was we got twice as many diesels as we need or three times as many diesels as we need. If they all break, surely we can get them running again in four hours. We were not thinking of tsunami.

The diesels are designed to survive an earthquake, but now we wonder, after Japan: Are there situations where something's going to happen we didn't think of and we have neither the grid nor the diesels?

GROSS: So how much of an effort is there now to have more diesels or more battery power or any other option that can help if a plant is compromised?

Mr. WALD: Well, the Nuclear Regulatory Commission has just begun a 90-day review, and it'll give interim reports along the way. And one of the things they'll look at is: How hard would it be to add more batteries? And is that the best thing we should be doing? They may come up with some other solution.

The reactors have always relied on the grid. When we had the big Eastern blackout in 2003, it took down a bunch of reactors, and we don't like cutting off outside power and letting the reactors screech to a halt because that's an opportunity for something to go wrong.

So over the years, there's been a lot of attention to this loss-of-offsite-power problem. Diesels are a little bit like a truck. They've got enormous batteries to get started, but every once in a while you have trouble getting an internal combustion engine started.

So this area has already gotten a lot of attention and is about to get a lot more.

GROSS: My guest is Matthew Wald. He's been reporting on nuclear energy since 1979. He's a reporter for the New York Times. Let's take a short break here, and then we'll talk more about the state of nuclear power in America. This is FRESH AIR.

(Soundbite of music)

GROSS: We're talking about the state of nuclear power in America, in the wake of the nuclear catastrophe in Japan. And my guest is Matthew Wald. He's been covering nuclear energy since 1979. He's a reporter for the New York Times.

So we're re-evaluating diesel power at nuclear plants, the battery lifetime to power a reactor if the electricity has gone out. Aren't we also re-evaluating what to do with spent fuel rods?

Mr. WALD: Yes. In the United States, at the time our reactors were designed, we anticipated that the rods would sit in these cooling-water pools for maybe five years and then be hauled off and chemically processed to recover plutonium that was made in the reactors while they operated, and then you can use the plutonium as fuel.

That technology turned out to be financially unfeasible, and Presidents Ford and Carter decided it was not a good example for the U.S. to set because if you're going to recover the plutonium, you can use it for bombs. So we didn't do that.

Then we set out on this long effort to find a place to bury nuclear waste. We had the government sign contracts with utilities. The government would start taking the stuff in 1998.

When President Obama came into the White House, he said that our prime candidate, Yucca Mountain, was not a good site, we weren't going to do that. Yucca Mountain might have opened in 2019 if everything went perfectly, but I don't think it was going to go perfectly.

Right now we have no date at all. So the pools have gotten more and more full. We have built some what we call dry cask storage, which is you take the older fuel that isn't making so much heat, you put it in a sealed steel can, you fill the can with something inert so it can't rust, and then you put the can into this little concrete silo, and it's cooled by air. And it can sit there for decades and decades without much difficulty.

You've got to guard it, but you don't have to do much maintenance. It's got no moving parts.

We may end up doing more of that now because we may be happier with a little less fuel in the pools. If you lose cooling in the pools, you've got many days to take care of the problem, but if you can't take care of the problem, you end up where Japan is now.

GROSS: These dry casks that some fuel is stored in now, they're licensed by the Nuclear Regulatory Commission for 20 to 40 years. But doesn't federal law say that nuclear waste has to be safely stored in canisters for a million years?

And, like, that's just - I can't even wrap my head around that. How do you know if something can withstand a million years of storage?

Mr. WALD: A million years is the Yucca Mountain problem that Nevada took the Department of Energy to court, and the Department of Energy was planning on a 10,000-year safe repository. And Nevada said that ain't what the law says. And the court agreed. The court agreed that you had to project ahead a million years.

The dry casks are a solution that will go for decades. The Nuclear Regulatory Commission initially licensed them for 20 years, put in an extension of another 20, recently went through this proceeding to decide that it was confident you could store in casks for decades after a reactor closed, meaning the casks are probably good for somewhere on order of 100 years, but we'll figure it out as we go along.

In that sense, it's not an urgent problem. But we don't, at this time, have a clear path forward on what to do after storage in casks. The president did appoint a blue-ribbon commission. It's supposed to report in the next few weeks. It could recommend a variety of things.

It could recommend a new way to find a place for burial. The method we used turned out not to be very good. The method we used was let Congress decide, and Congress is not great on geochemistry.

It could decide we need a new industry. We need either to go back to the original conception of reprocessing this fuel, pulling out the plutonium. You still end up with waste, but it's not quite so long-lived. Or a new kind of reactor that takes the really long half-life stuff and busts it up into shorter half-life stuff. So you then have a problem that runs to the hundreds of years instead of the millions of years.

But whatever we do is likely to cost money and is not likely to produce an instant solution.

GROSS: So if I hear you correctly, a hundred years from now, after we're dead, people are going to have to figure out what to do with these dry casks storing spent nuclear rods.

Mr. WALD: The cask problem is a problem, but it's a slow problem. You can - we now have casks sitting in places where we used to have reactors, but we've torn down the reactors. So we've got these spent-fuel storage installations. They're very high-quality concrete. They're surrounded by barbed wire, razor wire. They're lit. They're guarded. They look a little bit like a basketball court at a maximum-security prison.

But we've got them in dumb places. We've got them scattered around the country. And over the decades, we're going to have more of them scattered around the country.

If you've got one next to an operating reactor, it's not a big deal. If the reactor gets so old you close it up and tear it down, it then becomes just a pain to deal with. Certainly centralizing those materials would be one step.

If the cask eventually wears out, you could put it in another cask. We're not talking about an impossibly large volume of material. And as the decades go by, it does get easier to handle, although you do still have to handle the stuff underwater because you need the radiation shielding that the water provides.

But in the long term, yes, casks are not the answer. We're going to have to do something else.

GROSS: You know, we've been talking about some of the problems storing spent nuclear fuel rods. We've been talking about some of the environmental problems storing it. But there are political issues surrounding it too.

You had mentioned Yucca Mountain in Nevada, which was going to be developed into a storage space for spent nuclear fuel, but now that looks in question.

Harry Reid, the Senate majority leader and senator from Nevada, is opposed to this. He says it's never going to happen. President Obama is opposed to it. So do locations change depending on the makeup of Congress?

Mr. WALD: That's certainly how we picked Yucca. At the time that it was chosen, in the early '80s, the alternative sites were in Texas and Washington State, and both of those places had very powerful members of Congress and Nevada didn't. Since then things have changed.

Yucca was chosen by the finest geologists in the United States Senate, which is to say they may not have made the best technical choice. Yucca is an oddball in terms of its geology.

Around the world, countries are looking to bury nuclear waste deep in wet environments, because if you - if it's wet enough, you don't get into a rust problem. Yucca is, in theory, dry. In fact, the mountain turns out to have a lot of water running through it, and its geology presents different problems.

GROSS: My guest, Matthew Wald, will be back in the second half of the show. He's a reporter for the New York Times who covers nuclear energy and energy-related issues and technology. I'm Terry Gross and this is FRESH AIR.

(Soundbite of music)

GROSS: This is FRESH AIR. Im Terry Gross back with Matthew Wald, a New York Times reporter who has been covering nuclear energy since 1979. We're talking about questions that are being asked about the safety of American nuclear power plants and the storage of spent nuclear fuel in the wake of the Fukushima nuclear power plant catastrophe. Most of America's nuclear plants were built decades ago.

So if most of the reactors in America were built in 1973 or before, why did construction come to a halt after that?

Mr. WALD: The reactors were ordered in the '60s and '70s when we had very rapidly-growing electric demand. And then in 74 we had the Arab oil embargo. At the time we were using oil to make electricity and we figured reactors would be cheaper. We slipped into recession. The rate of growth of electric demand slowed and stopped and we ran into trouble building the reactors. We were building them too fast. We were putting up big structures before the designs were complete and costs got out of hand.

And as a result, even before Three Mile Island, that accident was March of 1979, we had a lot of utilities looking at slack demand, we're going to have too much capacity and they had huge cost overruns, so they stopped ordering and started canceling.

The situation looked like it might be turning around in the '90s and then after 2000, when the reactors were seen to have a new virtue, which is they don't produce carbon dioxide. And we got to the point where various manufacturers had come up with new designs. The government in 2005 said it would offer loan guarantees to help get the first few built and people started talking about a nuclear renaissance. We don't quite have a renaissance at this point. We've got two plants under construction, each with two units, and it's not clear how many more were going to get. But to be honest, it wasn't clear how many more we were going to get even before the Fukushima.

GROSS: Before Fukushima nuclear power was being basically rebranded as a green form of energy because, as you said, it doesn't produce greenhouse gases, although there has always been fear of, you know, meltdown and radiation and, you know, horrible consequences that aren't greenhouse gases but are other forms of dangers. How successful has that rebranding of nuclear energy been?

Mr. WALD: Before Fukushima, polls showed high tolerance, if not enthusiasm, at least tolerance for new reactors. Some of that has shifted. But the flipside is you don't need a national consensus to build a reactor in a particular spot. You need a local consensus. That consensus probably still exists in lots of places, especially adjacent to existing reactors. It means a lot of jobs. It means a continuing stream of tax revenue. But the financial situation may not be in place so it may not be public opinion that makes a difference here. It may just be the finances.

The biggest development in the electricity markets in the last two years isn't nuclear. It's that the price of natural gas has sunk to very low levels. This is a separate problem, it has to do with fracking, it has to do with other technologies. But the result is competition in the electric market has gotten stiffer and it really isn't clear you can make money building a reactor.

GROSS: How many nuclear reactor licenses are under consideration now by the Nuclear Regulatory Commission?

Mr. WALD: There are only two that are really active going forward. There are - the Southern Company wants to build two new reactors at its Vogtle site, which already has two reactors, near Augusta, Georgia. And there's an applicant in South Carolina who wants to build two across the Savanna River in South Carolina. There are others at earlier stages in the process, but it's not really clear, given the financial situation right now, even before Fukushima, how many of those are actually going to advance.

GROSS: Then there's also the issue of license renewal and are there a lot of nuclear facilities up for license renewal?

Mr. WALD: Yes. Of the 104 now running, more than half have already gotten a 20-year extension and almost all the others are going to apply. And we even have talk of extending - giving a second 20-year extension from 60 years through to 80 years. At this point that's just preliminary engineering work. That is a pretty narrowly-focused technical process in which the Nuclear Regulatory Commission looks at the parts of the plant that age, the wiring, the metal, etcetera, and asks the simple question: do these things get worse with age? What are we doing to see that they'll still work as they get older?

Now we got calls after Fukushima for let's hold off on relicensing till we know what happened at Fukushima. The NRC has thus far resisted that idea. It said look, if we find something out of Fukushima that shows a flaw in our reactors, we're going to order a fix immediately. Were going to order a fix whether it already got a 20-year extension, whether it was due for a 20-year extension two years from now, etcetera, but were going to go ahead with our relicensing process. That has annoyed a lot of people outside the agency, but that's where it stands right now.

GROSS: Now in New York for instance, Governor Andrew Cuomo does not want two of the Indian Point reactors to be relicensed. He's concerned for one that there are, theres a pattern of small but active faults that was discovered near there. And he's worried about like if something does go wrong how do you evacuate New York City? And what does that mean for the future of New York?

So what's that showdown looking like between Governor Cuomo saying I don't want these reactors relicensed and the NRC probably saying that they are fine to be relicensed? And, of course, the owner of the facility will want them relicensed.

Mr. WALD: In fairness, Governor Cuomo opposed the relicensing - license extension even before he was governor. The exact applicability of Fukushima to Indian Point has not yet been determined. I'm sure it will be or I'm sure we'll learn collateral lessons. Indian Point is in a somewhat different category, which is, it's not only a private asset, which by the way, the state used to own half of it, used to own and operate Indian Point Three - wasn't very good at it, but it owned it.

Indian Point is needed at the moment for its electricity production for adding stability to the grid. If Indian Point had to close, you'd have to make some other arrangements first. You'd have to build new transmission or probably new generation.

GROSS: So that would be quite a challenge. But nevertheless, the governor opposes relicensing two of those plants.

Mr. WALD: Well, Indian Point is an interesting case in the sense that its location doesn't make an accident any more likely; it simply makes it a little harder to cope with. The current emergency planning standard is you've got to plan for evacuations within 10 miles. If you had to conduct an evacuation or telling people to take shelter beyond 10 miles, you might have to do that but you don't have to plan for that in advance because you'll have time to do it.

The complicating factor right now is that the American Embassy in Tokyo has told Americans to evacuate 50 miles from Fukushima, something not contemplated as happening quickly in the American emergency planning guidelines. Now the emergency planning guidelines when in soon after the Three Mile Island accident in 1979 and since that time no evacuation or sheltering that I know of has ever been ordered. That's not to say it can't happen, but some people doubt that this is a likely occurrence.

GROSS: Now in Vermont there's also an ongoing fight this time between the state legislature, which doesn't want the Vermont Yankee reactor relicensed for another 20 years. They're arguing that the plant is too old to be reliable but the licensing seems to be moving forward. Yes?

Mr. WALD: I think whats happening in Vermont is interesting because the legislature is just literally wrong. And it's saying things that aren't quite so because it has a different motive. The plant, in fact, operates better now than it did in the past. It has fewer automatic shutdowns. It has more hours online every year.

What they're really worried about isn't whether it will shut down automatically, whether it will break down. What they're worried about is whether it's safe. But they're not allowed to regulate safety, that's a federal prerogative. So instead they talk about reliability.

And the Vermont Yankee plant had has some black eyes. One of them is it had a cooling tower, a low-rise wooden cooling tower, not one of these huge concrete hourglass things that collapsed. There were leaks from underground pipes around the country and Vermont officials asked Vermont Yankee whether it could have such leaks and plant officials said no, no, we don't have any pipes like that. And sure enough, it did have pipes like that and they did leak tritium. This was not a health hazard but it sure didn't look good to have the company executives testifying that were not going to have that problem and then we don't have those parts and then they do have those parts and they did have that problem. Its had assorted other problems over the years.

Vermont is really in an interesting position because when the reactor changed hands the state stepped in and said we want some control here. We want to be able to control whether the license is extended, and the buyer, Entergy Nuclear, agreed. So uniquely, the Vermont Legislature may in fact be in a position to prevent the plant from operating beyond its license expiration, which is about a year from now.

GROSS: Would that be unprecedented?

Mr. WALD: Yes. The only time that an American reactor a power reactor - has been shut by some kind of public action was the Sacramento Municipal Utility District in California. The voters of the district -its a muni, its a consumer-owned, a government-owned complex - voted to shut Rancho Seco just because it didn't work very well. That was in the '80s. This would be the second time. This time it would be a legislature not the voters.

GROSS: My guest is that New York Times reporter Matthew Wald. Well talk more about nuclear power in the U.S. after a break. This is FRESH AIR.

(Soundbite of music)

GROSS: My guest is New York Times reporter Matthew Wald. He's been covering nuclear energy since 1979. Were talking about safety issues relating to nuclear power in the U.S.

What have been some of the worst mishaps or, you know, accidents at American nuclear power plants since Three Mile Island?

Mr. WALD: Several come to mind. There was an incident at the Davis Bessie plant in Oak Harbor, Ohio. That design of reactor has a tendency to get small water leaks out of the cooling water and the water has boron in it, boric acid. And the reactor operators were told to check that they didn't have these leaks and it wasn't causing any corrosion.

First Energy, the company that owned the reactor, said well, yes, well check, but why don't you let us wait a few weeks (unintelligible) well shut down anyway? And the Nuclear Regulatory Commission, in a moment I'm sure they now regret, said well, okay, go ahead and wait. Well, when they finally shut down, they discovered that a huge chunk of the vessel head had rusted away and the only thing holding the pressure in the reactor was a tiny strip of stainless steel liner that was bulging, and that shook people up.

Other incidents, at the Salem nuclear generating station in Southern New Jersey, they had an incident in 83 where there is an automatic system thats supposed to shut the reactor down if it gets a signal from any one of three dozen places. And it's a redundant system. There are two breakers that should they get the signal, will cut power to the electromagnets that allow the reactor to keep running. The electromagnets hold the control rods out of the core, cut the power its supposed to be a very safe, passive design cut the power, the gravity pulls the rods down into the core and the reactor stops.

Well, both of these electric breakers failed simultaneously. The Nuclear Regulatory Commission had calculated this would happen been six times in 100,000 years. If you're good at math, that's once every 17,000 years, give or take. And it happened twice - because they didn't notice it the first time - it happened twice in a three day period.

What this tells you is there are sometimes connections between systems you think are independent - they thought these two breakers were independent but they weren't and there you can get problems we haven't thought of.

Thereve been a few other - there's a reactor in Florida right now that shut down to replace some major components and when they opened up the containment to get the new components in they discovered cracks in the containment, rust and cracks, and that was a couple of years ago when they were still trying to get it fixed.

These things sometimes work better than you think they're going to, more often they don't work as well as you think they're going to, and we have not yet exhausted all the theoretical possibilities of ways to go wrong. Although as time goes by, as with airplanes, you learn from experience and there are certain problems that you put to bed. You don't get a second time.

We had a fire at the Browns Ferry One nuclear plant before Three Mile Island in 1975, and believe it or not, we still have some unresolved fire issues at American reactors. We have a system in these reactors where if you get a major pipe break, the water collects in the basement and you pump it back into the reactor vessel. You have very high quality, high reliability pumps and valves to do that. But later somebody decided, you know, if we really get a big pipe break is going to scour the paint off the walls. It's going to take any debris that's handy and that's going to go to the basement too, and that's going to clog up the drains where the stuff collects and we won't be able to re-circulate it.

Weve been working on that problem for about a decade now and some plants have made improvements but we have not yet finished with those improvements. So there's a lot out there that could go wrong. Its likelihood is not clear.

GROSS: How much of American electricity comes from nuclear power now?

Mr. WALD: It's about 20 percent. And although we haven't built any new reactors in a long time, the reactors we've got run more hours of the year and some of them have been tweaked to get higher output. So even though national electric demand has grown and the reactor fleet has not grown - in fact, it's shrunk a little - we still have about a 20 percent share from nuclear.

GROSS: Where does nuclear power fit in President Obama's energy policy? And did the Fukushima disaster affect that policy, judging from his Wednesday address?

Mr. WALD: It did not. The administration officials have been careful to say we want to learn all the lessons we can from this. We're not going to be cavalier about this. And just because we're not particularly worried about tsunami doesn't mean there aren't things we can learn here to reduce our chance of accident.

But the administration has been pretty firm, partly led by Steven Chu, the Secretary of Energy, who has a Nobel Prize in physics, that we need to keep the nuclear option open. We need to understand how to build modern plants, in addition to operating those we designed and built in the '70s. We have an export business in nuclear technology. And the time may come when we want to build a lot more. We need to give the industry a little help to build a few now just to keep the technology alive. That loosely is - was and is the Obama administration, and the Bush administration before, it's policy.

GROSS: So, you know, where are we with energy now? You know, you look around and every form of energy seems to have serious consequences. Oil, first of all, it - you know, it produces greenhouse gases when burned. Also it makes us beholden to foreign countries, often countries that do not have our best interests at heart.

Mr. WALD: Not to mention all the guys we killed on the Deepwater Horizon...

GROSS: Yes. Right.

Mr. WALD: ...and all the beaches we fouled. We killed, we had a coal mining disaster in West Virginia last year. We had about 48 coalminers killed in Pakistan a few days after the Fukushima Dai-ichi crash meltdown. And we had...

GROSS: So you're talking about coal now too in addition to oil.

Mr. WALD: Right. Last year there were six workers killed at a hydroelectric plant in Colorado. Every form of energy extraction and conversion has two kinds of risks, risks to the environment and risks to workers, and sometimes risks to the public.

Nuclear power in the United States may in fact have killed people, but not at the reactors. We've done some nasty things to miners in the uranium business. The real question isn't is their risk. The real question is how much good does electricity do you, what risk do you incur creating it, transmitting it, etcetera, and where does the balance lie? You and I drink water. Water is processed in this country with electricity. Sewage is processed with electricity. I have a refrigerator that runs on electricity, and the supermarket down the street gets food to me through electric refrigeration. I've had X-rays. I've had a dentist drill my teeth, all with electricity. All of this has some cost.

GROSS: Well, Matthew Wald, I want to thank you very much for talking with us.

Mr. WALD: Thank you, Terry.

GROSS: Matthew Wald is a reporter for the New York Times who covers nuclear power. You'll find links to his recent articles on our website,

