[At top is the edited version of the interview published by S. L. Sanger in Working on the Bomb: An Oral History of WWII Hanford, Portland State University, 1995.
For the full transcript that matches the audio of the interview, please scroll down.]
I think I could tell you a little bit about the very early days when I was working with Enrico Fermi. I remember I had gotten my Ph.D and I was wondering what I would be doing, and Fermi persuaded me to continue to work with him. He felt, although I don't think he had at the time a clear idea of what was involved, that if you worked on the chain reaction, that would be the quickest way to producing a bomb.
There was a question of who thought of plutonium first, and the credit usually was given to Prof. Louis Turner of Princeton, who wrote it up in an article. He pointed out that if you captured neutrons on uranium-238, you ultimately made plutonium-239. I don't want to claim that Fermi already had that idea but the idea was taken seriously by Turner and that was a start. It had been presumed plutonium-239 was fissionable because of the Bohr-Wheeler theory that if the isotope was an odd number instead of even it would behave similarly to uranium-235. People were fairly convinced of that.
Hanford itself was a factory. The basic process had been worked out at Chicago and, to some extent, at Oak Ridge. Hanford was always referred to as the production plant. I was never at Hanford. I spent a lot of time at Wilmington [Du Pont's headquarters], in fact that's how I got to know Crawford Greenewalt (Du Pont's technical liaison with the Met Lab, and later president of the company). He wanted a scientist in Wilmington to consult and to help and give advice about the nuclear physics involved. I went there for not quite a year. I spent time designing the Hanford test reactor and looked over the plans for the big reactors to see if the design was sound.
A characteristic thing about Hanford is that the site is enormous, but the reactor is a very small thing and all the rest is water treatment. Most of the money went into water treatment. It isn't clear to me, but the weight of evidence is that it was more economic to build a water-cooled reactor than a gas-cooled one. Wigner and his group at the Met Lab designed the water-cooled reactor, and the Du Pont people took that design and turned it into a realistic engineering design and then Du Pont did the construction design.
Friction between the Du Pont people and the Met Lab scientists was always a problem. It was handled beautifully by Greenewalt. His key engineers learned a lot, worked hard, asked lots of questions. They weren't bashful about asking questions. Of course, there were always academic types who were very suspicious of big industries. They thought industries were out for themselves, making profit and so on. The fact of the matter is that the Du Pont Company, according to its contractual agreement, said it would be reimbursed for all costs and $1 profit. They certainly didn't make any money out of it. I think they looked at the whole enterprise from beginning to the end as a public service, and didn't want any suggestion it was anything but a public service.
I remember discussing it with Crawford Greenewalt when I traveled to and from Wilmington with him. I said I bet Du Pont will go into nuclear energy after the war and make a big thing of it because you know so much more than anybody else. He said, "No, we are going to go into nylon, and make nylon stockings. We can make more money that way."
You know, I discovered, it was a great eye-opener for me, an academic type with all the suspicions academics have about industry. It was an eye opener to discover how competent these guys were. How important it was to have not only the competence but also the number of people who got involved in this planning, that really was necessary. So many details have to be followed, and only by having a huge engineering organization can you attend to that. I think the idea that Wigner had that he could manage that is just unrealistic. There is no way an academic can learn quickly how to handle a vast engineering organization. I remember there were 300 engineers designing things, and attending to procurement problems, knowing whom to call, how to get the cement and the other things. That takes a vast experience, that Du Pont had. To General Groves' credit he realized that.
Nuclear weapons, well, that's a complicated question. On the one hand nuclear weapons are a disaster, and a major concern for all mankind and we would be better off not to have them. But we do have them. They do exist. You have to deal with that. It is unfortunate. Right after the war, I played a role with my associates to tell people how dangerous they were and that there ought to be some kind of international agreement. That never worked out. It is easy enough to say we don't need nuclear weapons. I guess I am sufficiently a hawk to feel that if you don't have a strong position militarily, nobody talks to you. I believe if you aren't strong, you don't have a voice. I believe we have to be involved in the decision-making process. You can't delegate political dominance to somebody else.
I did not work on nuclear weapons after 1945, but I don't turn my back on the weapons. Nuclear weapons are a great anomaly. Spending so much money on something you never will use.
Herbert Anderson: When I was working with Enrico Fermi, and I remember that––I had just gotten my PhD and I was wondering what I would be doing. And Fermi persuaded me to continue to work with him because he felt––although I don’t think at the time he had a clear idea what was involved—that if he worked on the chain reaction, that would be the quickest way. We would move successfully if we moved in that direction. That would be the quickest way to producing a bomb.
So even though the other enterprises were already underway, the separation of the isotope, that is, it was already––and I'm not exactly clear to what extent it was all that clear about plutonium. I mean, there's a question there about when the information came. And I've looked into that before but I've sort of forgotten how, you know, how the history went. It’s always a question of who thought of plutonium first.
And the credit is usually given to [Louis] Turner, he's at Princeton, he was at Princeton, who then wrote this up actually, as I recall in the Reviews of Modern Physics article in which he pointed out that if you captured neutrons on uranium-238, you would ultimately make plutonium. And that was a way to go. So I think that sort of emerged. I don’t want to claim that Fermi already had that idea. But the idea was already known. I think the person who's given credit for having noted that and taken it seriously is Turner.
But anyway, that was a start. And so it was clear that if you went by way of a chain reaction, and that meant the Metallurgical Lab of Chicago. Then that became the Hanford Project, that you were working on plutonium.
In a sense, we became the plutonium project in contrast to the isotope separation, which looked to for the 235 and which was known to be a fissionable a material. Of course, at the time all this was done people didn't know that plutonium would be fissionable. It was only presumed that it would be because of the Bohr-Wheeler theory and the idea of that the isotope was odd instead of even, then it would behave similar to 235. So people were fairly convinced that that would be.
And then one of the things that was done is, when Seaborg then separated out a small amount of plutonium, I, in Chicago got an early sample and we could test its––really its absorption and its properties.
S. L. Sanger: And that was done then?
Anderson: Yeah, some of that was done then.
Sanger: Did you work on that?
Anderson: Yes, I worked on that.
Sanger: That would have been about when?
Anderson: Well, let's see, that must have been in 1943, I would say. The dates are a little––
Sanger: So in a way the Hanford Project was well underway before it was for sure determined that plutonium was fissionable.
Anderson: Yeah. Well, I would have to check carefully, you know, the written documentation to settle those dates, but I would say so. I think that it wasn't yet known, but I think I would want to check on that.
Sanger: Yeah, I think I, in fact, recently read that that formally it wasn't known.
Anderson: No, it was just a bold assumption, which then, of course––because I think plutonium had not yet been separated by that time. And then, you know, it was only after the chain reaction had already been started and the DuPont people were already involved. After all, they got into it to see the first chain reaction test. I still correspond with Crawford Greenewalt––
Sanger: Do you?
Anderson: —who is the man who witnessed the first chain reaction.
Sanger: You were there, weren’t you?
Anderson: Oh yeah, I played a rather essential role.
Sanger: Why don’t you maybe—before I forget about it—why don't you describe that part, then we could come back to plutonium, the chain reaction, the role you played in that?
Anderson: Well, you know, I've gone through that ad nauseam. I had notes, and had written it all up and that's what's written in the––
Sanger: That’s mainly what's written in that article.
Anderson: Yeah, I've been writing that ad nauseam.
Sanger: Well, you know, I can get that from the article. I think it’s mentioned, you mentioned in there that until what the chain reaction—unless it was—until the chain reaction was showed to produce plutonium, that was a military aspect, right?
Sanger: And that was its value to the Manhattan Project, was the fact that plutonium was a result of that. Isn't that true?
Anderson: Yeah, the Manhattan Project was essentially a military project and the concern was to have something before the Germans did, and then later to have a weapon that might end the war. So that we were at the time of the Metallurgical Lab—well, we were under the direction of a General, after all. And we were essentially an Army enterprise, with a stated goal of making a nuclear weapon.
Sanger: In the interview I had with Norman Hilberry, he said that as he recalled that the scientists tended to think that perhaps they were only making maybe one bomb rather than many. And he recalled an instance when the General or the man who was in before Groves, I think his name was Marshall.
Anderson: Charlie Marshall?
Sanger: Well, it was a man named John. He was a Colonel, I think in the Corps of Engineers.
Anderson: Oh no, I see.
Sanger: He was before––kind of Groves’ temporary predecessor. And he told Hilberry––he took him aside, Hilberry recalled, and said that, “I get the impression the scientists think that there's only one bomb involved here. That's all we want to make.”
And Hilberry said, “Well, I don't know.” And the army man said that that wasn't the way the military worked, that once they made one they'd want to make many. Do you recall anything like that in your early days?
Anderson: No. But I think that it was always quite clear that there would one made of uranium-235 and one made of plutonium-239, so even when they came to use them, there were two different ones. And then there was the Trinity experience, which used up one of them, you see. So that the Trinity was already the first plutonium bomb, and then there was the Hiroshima bomb, which was a 235 and the Nagasaki called 239.
Sanger: In your recollection, how did the scientists at the Met Lab view the Hanford Works? Was it mostly considered just kind of like a plutonium factory more than anything else? I mean, was it considered any kind of a scientific center like Los Alamos was?
Anderson: Oh no, no, it was a factory.
Sanger: That's how they viewed it, was more like a factory.
Anderson: Yeah, I don’t think anybody had any other ideas.
The basic process had been worked out at Chicago and to some extent at Oak Ridge, and then the production plant always referred to as a production plant. So that was the place that was oriented and focused on the production of plutonium, you know, and no other object in mind except that there was a test reactor build. That was really only to test out––
Sanger: Where, the one in Oak Ridge?
Anderson: No, in Hanford.
Sanger: Oh, the one in Hanford, the materials––
Anderson: It was building 305 or something like that, as I remember.
Sanger: Yeah, but you never visited.
Anderson: I never went there. I spent a lot of time in Wilmington. In fact, that's how I got to know Greenewalt. He wanted somebody in Wilmington as a consultant really, and to help and give advice about the nuclear physics involved because the DuPont Company didn't have anybody in it that had previous experience with nuclear physics. And so they needed some consulting. And I went there for not quite a year.
Sanger: What did you do there exactly?
Anderson: Well, I essentially sat in the office with some of the other engineers who were intimately connected with the design, so that we had sort of a day-to-day interaction. And then I spent time designing this test pilot, I remember, which had not been designed. And then I looked over the plans for the big reactor to see whether the design was sound, and discussed the various problems that came up by just sitting there. We would always have a little discussion. They would always tell me what they were thinking about and what problems they were working on.
Sanger: Was there something of a scientific dispute over how to cool the reactors there?
Anderson: Well, not there. I mean, those discussions went on earlier. I mean, there was a lot of debate about cooling in the metallurgical project. And there were designs for helium cooling. And in the end, the water-cooling was promoted and then shown to be practical by Wigner's group. There was a big group under Eugene Wigner. There was quite a lot of question about whether it shouldn't be better to cool it with helium.
Sanger: But that was, of course, all settled by the time the––
Anderson: Well, I guess the DuPont looked at that and then decided to go to the waterway.
Sanger: Is it true that helium cooling would have required a great deal of electricity? Because one of the reasons that the Hanford site was chosen was because there was endless electricity there from Grand Coulee Dam. And I read a book recently that just noted very briefly that ironically, the water cooling didn't take nearly as much electricity and so perhaps they wouldn’t of had to of locate it there, in that otherwise very isolated place. But I don't know if that––
Anderson: Well, I don't know. I mean actually, as you know, helium cooling is a practical design [00:15:00] that is actually used by some of the––there are such plants that are––at least they are gas cooled, not necessarily helium, but gas cool.
Sanger: Was water considered simpler?
Anderson: I think it was decided that water would be simpler and I guess the best thing that could be said for it is that Wigner for some reason launched on that idea and then sort of showed that you could overcome all of the problems. I always remember, and that I think is a characteristic of the Hanford pile, that the pile is––I mean, the reactor site is enough but the reactor is just a very small thing, and all the rest is water treatment, you see. It’s hard to argue. You know, most of the money went into the treatment of the water and so it isn't clear to me, and I think it’s still not all that clear, that––although I guess the way of evidence is that it’s more economic to build a water-cooled plant than a gas-cooled plant.
Sanger: There's certainly plenty of water there.
Anderson: That's true.
Sanger: Now Dr. Wigner, was he the leader of the design team on those reactors more?
Anderson: Yeah, well, he had a group in the Metallurgical Lab that designed the water-cooled reactor, and then the DuPont people took that design and turned it into a, say, a more realistic engineering design and saw that it could be constructed. You know, they drew the––they then did all the construction design.
Sanger: What is your view of the relations between DuPont people and the academic types of the Met Lab? A certain amount of friction or––
Anderson: Well, that was a problem, but I think it was handled very beautifully by Greenewalt and his key engineers who came and simply dealt with the––learned a lot. I mean, they worked hard, asked lots of questions, you know, and came and weren't bashful about asking questions and found out everything they needed to know. Of course, there are always the academic types who were very suspicious of industrial, you know, these big industries felt that they were always out for themselves and making profit and so on.
I mean, the fact of the matter is that the DuPont Company, according to its contractual arrangement, said that the profit would—they would be reimbursed for all the costs, and one dollar of profit. You know, they certainly didn't make any money out of it.
Sanger: And then they left right away, didn't they?
Sanger: They left right after they––when the war ended, DuPont left Hanford.
Anderson: As soon as they could, yeah.
Anderson: But then they got involved again in this––
Anderson: I think they looked at the whole enterprise from the beginning to the end as a public service and didn't want there to be any suggestion that it was anything else but a public service. And I remember discussing it with Greenewalt when I traveled to and from Wilmington sometimes with him. And I said, “Well, I bet the DuPont Company will go into nuclear energy after the war and make a big thing of it, because, you know so much more than anybody else.”
He says, “No, we're not going to do that. We’re going to go into nylon and make nylon stockings. We can make much more money that way.”
Anderson: And that's what they did.
Sanger: Were you working for DuPont then? Is that where your money and check came?
Anderson: Well, I didn't really break my connection with Chicago. I was sort of on leave with the idea that I would go back to Chicago, and then I did. So in other words, when most of the—when the hump of work was done, I went back to Chicago.
Sanger: You came to Los Alamos then?
Anderson: Shortly thereafter I came there.
Sanger: And then you stayed here till the war ended.
Sanger: Then what happened to you then after that?
Anderson: Well, then I got a faculty appointment in Chicago. So I then became an assistant professor, along with John Marshall, actually.
Sanger: Oh, did you?
Anderson: I mean, we worked together and built a big cyclotron together. We were close collaborators building a cyclotron. As for Chicago, we both went back and became assistant professors, and then both stayed there except that John Marshall then quit at a certain point and came to Los Alamos. And I stayed until I finally retired.
Sanger: Oh, you did. You retired as a professor in Chicago?
Anderson: Yeah, I had Professor Emeritus from Chicago. So about eight years ago I––well, in fact, I formally retired in 1982. That's four years ago. But I really came here about eight years ago.
Sanger: Oh, and what are you doing here?
Anderson: Well, I'm doing some biology.
Anderson: I'm working with some biologists on analyzing proteins that are made in cells.
Sanger: Oh, is that right?
Sanger: Is that a physics discipline or––
Anderson: Well, I essentially built the instrument that would measure them. That's what you see over here.
Anderson: Those are proteins. I'm looking at proteins made in cells, and then I work with a biologist, who actually just was here today. And it’s a good thing we're not doing this tomorrow morning, because I made a date to see him tomorrow morning.
Sanger: Oh yeah.
Anderson: Anyway, he does the biological part and I analyze the gels. And well, I have all this problem with my lungs, you see, so I'm really very limited in sort of the activity that I can do.
Sanger: You live, what, near Santa Fe?
Sanger: Where do you live, near Santa Fe?
Anderson: Well, I live halfway.
Anderson: I live in the valley in between. What's it called? Poechunu Valley.
Sanger: Before I go, I'd like, if you could, I'd like if you could talk just a little bit about Dr. Fermi, since I take it that you were very, very close to him for years.
Anderson: Yeah, from about the time he arrived until he died, when he came to Columbia. I mean, you've read the book, Atoms in the Family.
Sanger: Uh-huh, by his wife?
Anderson: Yeah. So he came to Columbia when I was a graduate student there, and then I sort of attached myself to him because––at that time, as I think I explained it in many articles that I've written, that I had this encounter with Niels Bohr and learned about fissioning and got interested in it. And then began to work with Fermi on the fission and toward the chain reaction, which everybody recognized would then become possible.
Well, we had a very close collaboration and friendship in which we sort of worked very well together. And then essentially when he went––well, starting at Columbia where initial experiments were done, the ones that proved out that carbon or graphite would be the way to build a chain reaction as the means of slowing down the neutrons. Then we went to Chicago, and then he went to Los Alamos and I followed him there. And then he came back to the University of Chicago as a professor, and I came as an assistant professor.
Sanger: Would you say that he was one of the two or three or most important scientists in the Manhattan Project?
Anderson: Oh yeah, no doubt. Yeah, he was.
Sanger: There wouldn't have been anybody who had done more scientific work, would there, basic work, than he had over those years?
Anderson: Well, I guess he has to his credit that he made the chain reaction work. I mean nobody takes that away. And that certainly was a key element. And then he went towards Los Alamos and we worked more or less somewhat together there. And there we were involved in such things as determining how to design the bomb, made measurements on the bomb design, and made measurements on––well, the main thing that I did then was to measure the efficiency of the bomb, how much energy was––that’s a picture of the bomb. That's the Trinity bomb down there.
Sanger: Here, where?
Anderson: No, no, that one in the middle over there.
Anderson: That's done with a handheld movie camera.
Sanger: Oh, who took that?
Anderson: You know, I took that.
Sanger: Oh, you took that.
Sanger: You must not have been looking directly at it though, right, when you took it? Is this just after the detonation, I guess, huh?
Anderson: Yeah, it’s looking at it with dark glasses.
Anderson: Pointing the camera at it––
Sanger: With a movie camera?
Anderson: Yeah, a movie camera.
Sanger: Marvin Wilkening was in your group, right?
Anderson: Yes, he was one of the men that was in my group.
Sanger: And your job was, what, to measure the efficiency of it?
Anderson: Yeah. What we did was, we collected out of the dirt—see, the bottom exploded, then it forced a lot of the dirt into the ground. And we picked up samples and analyzed the samples for plutonium and for the fission products. And by measuring the fission products and measuring the plutonium, you could tell what fraction of the plutonium actually underwent fission.
Sanger: Did you arrive at the yield that way?
Anderson: Yeah, I produced the only really reliable figure.
Sanger: Which is what, about what, 20?
Anderson: No, it was about 17 percent.
Anderson: The only real reliable figure was the one that I got from those.
Sanger: Is that––17 percent, was that considered pretty good?
Anderson: Yeah, it was surprisingly high. In fact, there was a pool in which I could not participate for those who wanted to guess that efficiency, and it was run by [Isidor I.] Rabi, who had simply said it would be the highest number. I think he gave a number like five percent, and it was even higher than that, surprisingly, surprisingly high. Everybody was surprised. It was much more powerful than anybody had expected.
Sanger: Have you over the years changed any of your ideas on nuclear weapons that I presume you had during the Manhattan Project years?
Anderson: During the years––
Sanger: That you've become less—I mean more, what, dove-like, or whatever, over the years or not?
Anderson: Well, that's a complicated question. Well, you know, there's lots to be said about all of that. On one hand, you know, they're a disaster and a major concern of all mankind. And it would be better not to have them. But we do have them. I mean, they exist and you can't erase that. That's a fact and you have to deal with that. So although, you know, it’s unfortunate that it's all evolved the way it was. Right after the war, I played a role with many of my associates to try to go around and tell people how dangerous they were and hope that there would be some international type of agreement, but that never worked out. And it still seems to run into trouble. And the real problem is, how do you deal with that problem? It’s easy enough to say that we don't need any nuclear weapons and we shouldn't have any, but then when you come down to political questions involved.
No, I guess I'm sufficiently a hawk to feel that if you don't have a strong position militarily, nobody talks to you. You don't have a voice. So I believe that we have to be involved in the decision-making process. You can't let the––delegate the political dominance to somebody like the Russians. Yeah, I'm not enough of a dove to say, “Okay, we can just disarm completely and let the others decide.” I don’t think that we're sufficiently trustful.
But it would be nice if people would only agree and take––so I've been interested in whatever methods that would increase the confidence and trust among the people who are involved, and dream occasionally that advances in technology might actually break down barriers, you know. I noticed there's considerable––well, let's say, there's some degree of––I tend to be an optimist. So I look at the developments and see how the technology has really brought more understanding and has made it more difficult to conceal things. Ultimately I hope––and of course, I don’t know, but ultimately I hope that these mistrustful aspects of our international society will somehow get diminished just because we have much more easy exchange. TV plays an intensively powerful role making it very difficult for anybody to conceal their misdeeds.
Sanger: Did you ever work on weapons after '45?
Sanger: You went back to the university?
Anderson: Well, I went back to the university and I was there for 30 years. And then I came here [Los Alamos] and although this is a weapons lab, I principally work on basic research. And that's what I was invited to come to do and that's what I've been doing. But I don't turn my back on the weapon. I recognize that––well, I recognize that one has to have a strong defensive posture for the reasons I mentioned, just so didn’t let other elements of our society take over.
On the other hand, there's a tremendous amount of waste. It’s a whole enterprise in which an enormous amount of money is spent and everything is meant hopefully not to be used. So everything is obsolete. You know, you built weapons and the guarantee, or at least the hope is that you'll never use them. So why spend all the money? It’s really a great anomaly.
Sanger: Do you recall Dr. Fermi talking much to you about his business to Hanford, any impressions he may have passed onto you?
Anderson: Well, I remember when he went there, because when he went there there was that great––I mean that great, what do you call it—the great question of xenon, the xenon poisoning. Of course, I was in Chicago and we got all kinds of telephone calls to check up on one aspect or the other. And Fermi actually was at Hanford at the time. So he was witness to it. And so he participated in the unraveling of that mystery and curious. So that was a great event. And I don't know whether you've ever read Compton's book?
Sanger: Yeah, Atomic Quest, that one, Atomic Quest.
Anderson: Yeah well, there's a very nice poem in there called “Homage George,” the DuPont people take great pride in satisfaction of having put enough safety factor into the design. And I remember that in particular because I was involved in that when I was in Wilmington. They wanted to put in lots of safety factor. And of course, the academic types tried to argue there's a tremendous waste of money, but it turned out to be a saving grace. They should get a lot of credit for that, you know, using sound engineering principles, lots of safety factor, put it the money, but don't take so many chances. Certainly didn't know it was going to happen, but they didn't know it might not happen, so they went ahead and did that. And except for that, [00:36:00] the Hanford reactors would have been a great failure.
Sanger: Now what could they have done if they hadn't put in enough?
Anderson: Real trouble.
Sanger: Would it have been possible to add them or not? I mean, I guess you couldn’t, because the building was designed for a certain size, wasn't it?
Anderson: Yeah, they would really be in real trouble. You know, it’s one of those––because what it meant was that as long as you were making xenon, you couldn't raise the level of operation of the reactor beyond a certain point. It would just poison itself and stop, you see. So that meant that the production of plutonium would be at a very low level.
I suppose ultimately, what you would do, but nobody was prepared for that, would be what they do now, they just enrich the fuel. And what they would have to do is work out methods of getting rid of the poisons and putting lots of chains of fuel elements very much more rapidly, and all that sort of thing. But it would have been a disaster, because, you know, you might be able to get it working ultimately, but the point is that we were in a war and time is of the essence. So it was really one of those saving things.
Sanger: And the other ones were––the other reactors were well along too, so it wasn't as if they could have in mid-stream made them a lot bigger without a good deal of trouble.
Anderson: Well, they would have to have done that, you know, but that would––you know, the way those things are organized everything has to be planned, and the whole logistics has to be very careful with. In fact, that's what they're doing, in Wilmington is just––you know, I discovered––it was a great eye opener for me.
I was an academic type and always had all the suspicions that academics have about industry. It was sort of an eye opener to discover how competent these guys were, you know, and how important it was to have not only the competence but also the number of people that get involved in this planning is really necessary. So many little details that have to be followed and only by having a huge engineering organization can you attend to that.
I think the idea that Wigner had that he could manage that was just unrealistic. There's just no way for the academic type to learn quickly how to handle the vast engineering organization. I remember there were some 300 engineers who were designing things and attending to the procurement problems and knowing whom to call up and how to get this and that and the other thing. You know, that takes a vast experience that you only have—and to General Groves’ credit, he realized that, you know, he knew that. And so he was very anxious to get the DuPont Company into it because he knew that they had all that skill and organization and know-how to really make it work.