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National Museum of Nuclear Science & History

Robert S. Norris’s Interview (2002)

Robert S. Norris is a senior fellow at the Federation of American Scientists and author of the definitive biography of General Leslie R. Groves, “Racing for the Bomb: General Leslie R. Groves, the Manhattan Project’s Indispensable Man.” In this interview, Norris provides an overview of how the Manhattan Project began, how the project sites were selected, and the role of British scientists in the project. He discusses the fear that many Manhattan Project scientists felt that Germany would develop an atomic bomb first. He explains Groves’ background, why he was the perfect leader for the project, and how he involved industry, especially DuPont, to help with the project. Norris contends that the Manhattan Project was a unique program in American history and would be difficult to replicate today.

Date of Interview:
September 12, 2022
Location of the Interview:


Robert S. Norris: By the late 30s, physicists, in Europe primarily, but some in America too, were making great discoveries about the atom. The key date here was January 1939, when European scientists had discovered fission. News of that was brought to the United States by Niels Bohr. Actually, it was brought to Washington, DC, at a conference at George Washington University.

Bohr and his fellow scientist, Enrico Fermi, and others announced it to the assembled and immediately everyone knew that something very significant had happened and possibly even something very fearful, in that this new discovery could be turned into a form of energy, a vast destructive power.

Just at the same time as World War II was about to begin in 1939, and of course it did begin on September 1, 1939, this new discovery of physics came at the same time. They share, then, a history of the war from then on.

Cindy Kelly: Just because it makes a good visual, you mentioned the conference in Washington, DC. Can you just mention that to verify this new phenomenon, they went to the Carnegie Institution in Washington?

Norris: At the conference at George Washington University in January 1939, in which most of the famous scientists and physicists in the world were assembled, upon the news of the fission discovery in Europe, all of the scientists in the United States saw that it was a major breakthrough. Many went to the Carnegie Institution of Washington to verify the experiments again and reconfirm what Bohr had just told them.

Kelly: Can you talk about Albert Einstein and his letter to Roosevelt?

Norris: After this new knowledge had become widespread among the scientific community, a few of them decided that something was going to have to be done to alert the government and alert each other about the implications. Leo Szilard, a Hungarian refugee who had made his way to the United States, Edward Teller, also Hungarian, got together and decided that they would alert the most famous scientist of the day, Albert Einstein.

In the summer of 1939, they drove out to Einstein’s summer house and had Einstein write a letter to President Roosevelt alerting him of the significance of this discovery. Through an intermediary, a man named Alexander Sachs, they got the letter delivered to Roosevelt. That’s usually considered to be the first step in the United States government’s effort to begin working on the bomb.

Kelly: Can you talk about Roosevelt creating the Office of Scientific Research and Development?

Norris: After Roosevelt had received this letter, he committed a small amount of money to an effort. But in the United Kingdom, in Great Britain, their scientists were actually far ahead of American scientists in working on a lot of this. They put together a government committee that became known as the MAUD Committee, and issued a report known as the MAUD Report. In there, the scientists concluded that a very small amount of a certain isotope of uranium could produce a very large bomb.

This happened in the summer of 1941. News of this came back to Washington. Franklin Roosevelt’s science advisor, a man named Vannevar Bush, who oversaw the Carnegie Institution of Washington, of course, but then also the government’s effort to begin to mobilize science for a war effort. Bush was briefed about this conclusion that they had come to in Great Britain, and was highly impressed with the possibility that this now may become a reality.

That’s a kind of key date in the history of the decisions about the bomb. Bush then feels more confident in going to Roosevelt and telling him that, “This is a serious matter and we have to commit more resources to the effort.”

Kelly: Maybe you can talk about how Bush looked to the industry.

Norris: By the middle of 1941, the effort is becoming more and more serious. More scientists are involved in investigating this special material, uranium, and how to gain a certain kind of uranium that would be useful for a bomb. As 1941 wears on, towards the end of the year, Bush is more convinced that this is going to be a large effort, and we are going to have to recruit the Army to do this.

We are in the midst of a very large mobilization at this point. Many people, including Roosevelt and Secretary of War Henry Stimson and George Marshall, are all quite sure that war will happen eventually. Preparations are being made in many ways, through the draft, through munitions plants and so on and so forth, to prepare for this war.

Actually, on the eve of Pearl Harbor, on December 6, Vannevar Bush and some other scientists decide that it is time to really recruit the Army into this effort. Of course, the following day is Pearl Harbor and everything is changed dramatically. It’s really towards the end of 1941 that the government is now really committed on a large scale, and signs up the Army to do the job.

After December 6, of course, the country is faced with now Japan being the enemy in one theater in the Pacific and Hitler declaring war on the United States at approximately the same time and now committed to a European war as well. Everything needed to be done with the vast numbers of men to be trained and sent abroad. The bomb effort sort of lingered for a few months, and it’s not really until mid-1942 that Bush again gets the ear of Roosevelt and Stimson and Marshall to get really serious about it.

It is at that point, in June of 1942, that the Army chooses the first director of what will become known as the Manhattan Project. That was a colonel named John Marshall, a Corps of Engineers West Point graduate. In June, he begins to do some things to mobilize industry and science and the military towards building the bomb. But throughout June, July, and August he’s not moving very quickly.

Vannevar Bush and his counterpart, President of Harvard James Conant, are dissatisfied at the pace of activities. If this bomb is going to make a difference in this war, it’s going to have to move faster. So Bush and Conant press Stimson and Marshall to find someone else who can move at a quicker pace. It is at this juncture that the Army chooses another colonel, Leslie R. Groves. On September 17, 1942, Groves learns of his new assignment. He is not terribly happy about it, but being the good soldier that he was, he salutes and takes the job.

These are the crucial dates in the formation of the Manhattan Project. Groves, at the time, was basically John Marshall’s boss. Thus he knew some of what was going on, or not going on. They were already surveying the sight at Oak Ridge, Tennessee. Thus Groves had quite a bit under his belt already, even before he got the job, in the way of knowledge. 

On September 17, it is now in his hands, and it’s really rather breathtaking to watch Groves over the next couple of weeks make enormous decisions that will be crucial in the formation of the Manhattan Project in its organization. One of those decisions early on within the first couple of weeks is to choose—to think about DuPont as the participant in this effort.

Kelly: Can you mention that Groves built the Pentagon? And then you can talk about the DuPont connection.

Norris: The reason why Groves was chosen was that he had already had a track record for the past two years. Basically, he was in charge of all Army building projects during the mobilization period, from about mid-‘40 to mid-‘42. This was an enormous undertaking, which actually is about four times the Manhattan Project if you total up the money. At the peak month, which is July 1942, Groves oversaw over 700 million dollars of projects and had a million men working for him. Among those 100 plus projects, which included munitions plants and Army camps, airfields, depots, one of them was the Pentagon. This is, I suppose, the second thing that Groves is known for.

In September 1941, just on the eve of what will be Pearl Harbor, the War Department decides to consolidate itself under one roof from buildings all over town. In rather dramatic fashion, they lay out this enormous building and ground is broken, coincidentally enough, on September 11, 1941. In six months, the first people move in to the first wedge, the first section. In sixteen months, the building is done. Of course, the building remains today one of the largest office buildings in the world. Groves oversaw its construction, sort of like an Egyptian pharaoh, with 15,000 workers working around the clock to get it done. It stands today as a testament to American knowhow in getting something done quickly. Groves was always proud of that feat as well.

Among these many, many projects that Groves was overseeing in 1940, ’41, and early ’42, were munitions plants. He knew DuPont because I believe he built eight munitions plants with DuPont over the course of time here. Thus Groves knew the executives at DuPont in Wilmington. He knew their engineers. He was very impressed with the way they got things done. Basically, DuPont was his first choice when he decided to have a facility for the plutonium production.

That came about, as I said, in September, October, and November of 1942. Groves called some executives down to Washington to his office, and informed them of his wishes that he wanted DuPont. They carried the news back to Walter Carpenter, the president, who was probably not too happy about this, with a full plate of their own already and now being asked to participate in something that was quite uncertain and had the potential for failure.

Nevertheless, Groves pressed on President Carpenter. Carpenter went to his Executive Committee and said that “The country needs our help.” Without really knowing what it was that they were signing up for, the Executive Committee gave Groves the okay, and thus DuPont was on board for the grand sum of a dollar.

It was the beginning of DuPont’s involvement in the Manhattan Project.

General Groves, in these first few months here, was making enormous decisions about where to put the factories that were going to produce the atomic materials for the bombs, about where to establish a laboratory, about what personnel were going to work on it. After he decided not to put this plutonium reactor, or pile, at Oak Ridge, he had to find another place for it. In December he sent one of his trusted aides, a man named Franklin Matthias, and two DuPont engineers—one who will become very, very involved, a man named Gilbert Church—out to the West Coast to look at a series of sites that were possibilities.

They looked in the Pacific Northwest. On December 22, 1942, Matthias got a small airplane, and he flies over what will become the Hanford Site in southeast Washington. He knows immediately that this is going to be the place. It fit all of the criteria that Groves wanted: it had to have an abundant source of water. The Columbia River is there. It had to have an electrical system nearby, and Bonneville Dam was there, just completed, and the Grand Coulee. It had to have a mild enough climate so that work could go on pretty much all year round. In the high area of southeast Washington, that fit the bill. It was quite isolated. For Groves’ penchant towards secrecy and everything, that was good as well.

Matthias called Groves immediately afterwards, and it was pretty much settled by the end of the year. Matthias comes back with a report. Groves is fairly convinced that that’s the place, but wants to see it for himself. He goes out in mid-January ’43, looks it over, and concludes that this will be the place. At that point, the government takes over a vast area of land. This is 500 square miles. It will eventually be half the size of the state of Rhode Island.

Ground begins to be broken at Hanford for what will be initially three reactors and two chemical separation plants that will be the place where plutonium is produced. At this point, Hanford, the little town that was there, is sort of transformed. Eventually, I think at the peak there were more than 50,000 people at the Hanford Site, the workers constructing the place and everyone else.

DuPont is there, not only to design and build the plants, but also Groves demands that they operate them as well. So they are in for the complete range of activities at Hanford, and do them all very well.

DuPont was a good fit for Groves’ plans here to oversee plutonium production. Of course, the story of the bomb is not just a story of physics. It’s also a story of chemistry, engineering, and many other things. DuPont was very well known as a chemical factory, and did a great deal in munitions work. Groves was attracted to that, and also to what he saw in the way that DuPont managed itself and managed projects.

Later this will become used by everyone, but in the 1930s and early ‘40s, it was something rather new and really almost unique, I think, with DuPont. The phrase that’s used is the “critical path scheduling” or “critical path method.” What it means is a very attentive, structured way of going about whatever you are doing here. Every worker knows exactly what he is going to be doing that day. There is follow-up to see that he has done it, a lot of quality control. These were the things that Groves saw about DuPont in the building of the munitions plants. He knew that this was a more efficient way of managing a large industrial enterprise. Thus to put it into place, to build something as experimental as atomic piles and chemical re-processing, was going to cut down on the uncertainty of whether or not it will be done.

I think this is Groves’ insight into DuPont’s way of doing things. That is another basic reason why he chose them. Much that went on at Hanford is related to chemistry, metallurgy, and the chemistry of plutonium extraction and so on. So the chemists also play a major role in the Manhattan Project. It’s not just the physicists, who have gotten most of the limelight. The chemists deserve their share as well.

Kelly: Can you talk about Crawford Greenewalt and the reviewing committee, how they went out—the DuPont one—to make sure that they did not get the least likely to succeed process assigned to them?

Norris: Groves was making all these decisions here. But he hadn’t always convinced everyone else who needed to be convinced, his superiors like Vannevar Bush and Conant and some others who may have been hesitant about all of this. In time-honored fashion, he assembles a committee to look into a matter—this is in November and early December of 1942—to really see if the things that are now going forward here are the right things.

The basic audience for this will be Crawford Greenewalt, who is based in Wilmington and will become a person who provides a kind of liaison, an intermediary, between DuPont in Wilmington, DuPont in Hanford, and really the third leg, which is what goes on in Chicago. Because at the University of Chicago, at what’s called the Met Lab, or the Metallurgical Lab, are assembled a bunch of scientists, chemists, engineers, and physicists who are the support for many of the blueprints, designs, and concepts upon which Hanford will be built. So Crawford Greenewalt plays a key role in all of this.

By the end of the year, certainly in 1942, as a result of this committee that Groves had formed, which basically supported these decisions, everyone is on board and convinced that the project has a chance of working and it is worthy of going forward.

Of course, uncertainty hung over the whole thing, from the beginning until July 16, 1945, when the first bomb was tested in New Mexico. In retrospect, it all looks as though it were inevitable and going to happen, but trying to put yourself on the other end, there was uncertainty and fear of failure at every juncture. That must have been felt by all of those involved, including General Groves and Crawford Greenewalt.

Greenewalt had already had a sort of track record himself within the DuPont Company of working, I believe, on the nylon project and seemed to have the kind of personality that was right for the job.

Among General Groves’ skills, in addition to the managerial ones of overseeing big projects, he was a pretty good judge of character and sizing people up almost immediately to know whether or not they were right for the job. In meeting Greenewalt, I’m sure he was impressed and saw in him what was needed for this task, which was to keep the scientists working, keep them calm, under actually what some of them thought was rather strict discipline. They were part of an Army project, for example. They were to work in great secrecy, the very opposite of the scientific credo. Greenewalt was there to smooth the feathers of the scientists and make everything go smoothly.

He and Groves got along very well throughout the whole course of the war. In fact, even after the war there was some thought of perhaps General Groves going to work for DuPont, but he never approached his old friend, Crawford Greenewalt, to ask.

At one juncture, though, he did have to discipline Greenewalt. Greenewalt had begun to write a diary, in secret, actually. That diary exists today and is in the Hagley Museum in Wilmington. Groves had ordered, across the board, that no one was to keep a diary. When he found out that Crawford Greenewalt had been keeping a diary, he ordered him to stop. Greenewalt, being the man he was, stopped immediately. Thus the diary comes to a rather sudden end and is not continued.

One very good example of DuPont’s approach to projects is the example of when they turned the first reactor on at Hanford. This reactor was designed by a group of scientists in collaboration with DuPont engineers and scientists. It was decided to put roughly 2,000 tubes into the reactor that would be filled with uranium rods. When those began to go critical, that’s the process out of which plutonium is produced.

In September of 1944, as the reactor was finished and they first turned it on, it started up and then it stopped. Everyone thought, “What could the problem be?” The problem was that they had only filled about 1500 of the tubes with uranium rods. Through a process of what goes on inside the reactor, xenon, X-E-N-O-N, is produced, and it sort of poisons the reactor and it causes it to stop. Had the reactor been built with only 1500 tubes, the reactor never would have been able to work, and plutonium would not have been ready less than a year later for the bombs at Trinity and Nagasaki. 

So basically what you can say is that DuPont took an approach of sort of always overbuilding whatever it was. If a building was going to be three stories, they would make the construction strong enough to have five, since probably at a later date they would need that. Here they built a reactor with 2,000 tubes. Eventually, after this poisoning incident, they halted the process and they filled the other tubes. When they started it up again, it was powerful enough to overcome this poisoning and it worked. It worked as it was supposed to.

This would be a good example of competing ideas about how to build something. The scientists actually, many of them, were for building the smaller one. It would have been quicker, faster, maybe less expensive. But Groves heard DuPont out and, being very conservative always, decided to go with the larger one. It is a good thing they did. Otherwise, the bomb would not have been ready and used when it was.

Kelly: Can you talk about the chemical separation plant, and the novelty of trying to do something with radioactivity and using remote control operations?

Norris: A plutonium production reactor is highly radioactive. After it is irradiated inside the reactor, the fuel is pushed out the back and sits in a cooling pool. Then it is transported to a chemical reprocessing plant, where the plutonium that is bred inside the reactor in the tubes is separated from the uranium.

Now all of this is a very, very messy business here. This is highly radioactive, highly hazardous, and human beings cannot be in direct contact with this. All of this then had to be done through remote control, basically, with little carts, little trains taking the fuel from the reactor to the chemical processing plant, through the use of remote control arms, and even the use of television. This is one of the early uses of sort of industrial television to separate this plutonium in these acid baths and extract the very, very tiny amounts of plutonium from the very, very large amounts of uranium fuel. Chemical reprocessing is, right from the very start, very, very messy.

From that day until this one, since we continued to do this at Hanford and a couple of other places throughout the Cold War, we produced an enormous amount of radioactive, high-level waste. Much of it still sits in the same tanks that were built in the Manhattan Project, and this legacy is still something we are grappling with, trying to figure out what to do with it.

Kelly: I would like to have you talk more about the health and safety issues and environmental issues, and what was known and not known, and how things were handled.

Norris: From the outset, the scientists—and I think General Groves himself—knew that the potential for accidents and hazards of one kind or another around these radioactive materials and on this huge industrial scale were possibilities. Obviously, it wasn’t the best place to build these huge things in cities or nearby.

Groves set up a medical health section within the Manhattan Project, and recruited doctors who had some knowledge in this new area of public health having to do with radioactivity. The person he signed up was a University of Rochester doctor named Stafford Warren, and he oversaw studies about health matters.

Groves, I think, sort of symbolizes what’s always the case, what always has been the case, in the U.S. atomic bomb effort, and that is trying to balance the speed of producing bombs with environmental and safety on the other hand. The more environmental concerns and things about safety are going to slow down the production of bombs. This is always something that is managed over the years. Groves was, I think, probably fortunate that no catastrophes occurred, although he saw the potential for them. What if one of these piles blew up? What if at Oak Ridge too much highly enriched uranium was in one place and went critical? He had Edward Teller investigate this problem, and Teller came away saying that these separation plants in Oak Ridge were going to be safe and it was okay. This was always a potential problem. 

Throughout the course of the Manhattan Project, people were killed in industrial accidents. These large machines took their toll. All in all I think the safety record was about the same, or actually a little bit less than, what went on in tank factories or other kinds of large production facilities.

It will become more evident after, I think, the bomb is used. The American public and then the world will become aware of radioactivity and become much more sensitive to all of these things and put into place things to try and combat it in making of the bombs, and then of course in things like testing bombs in the atmosphere. That will go on from 1945 up until the early ‘60s among the superpowers. Finally world opinion says “Stop,” and there is a test ban of testing weapons in the atmosphere and it stops. 

It’s something that we are aware of everyday when we talk about these weapons. It was mentioned before about the Normandy invasion, and how the Germans might potentially have some sort of radiological weapon, what today we call a Dirty Bomb, and perhaps would use that on the invading troops. Groves alerted Eisenhower of the possibility. Eisenhower did take some action with his British counterparts to have certain soldiers who stormed the beaches in Normandy have basically detectors on them. If any of them saw that they had gone off, they were to alert their superiors that something had happened. Of course, that didn’t happen, luckily. The Germans had no radiological bomb, but it was a concern even on D-Day.

Kelly: l never knew that.

Norris: Project Peppermint, it was called. The operation was called Project Peppermint.

Unidentified Male: How did the fear of what was not known about what the Germans were doing with their bomb project fuel the Hanford project and the Manhattan Project in general?

Norris: From the very outset of the discovery of fission, among the best scientists in the world were Germans. Really from day one, especially in the minds of some of these émigré scientists who would come to the United States, was the fear that German scientists working for Hitler were going to discover this first, and whoever got the bomb could rule the world. So as an incentive from day one, fear of the German bomb project was uppermost in many scientists’ minds and certainly in General Groves’ mind.

From the outset, it was Groves’ desire to learn as much as he could about the German effort. We did not have spy satellites. We did not have overflight of Germany the way we could do some things today to find out what was going on, so every scrap of information was important. And of course when you do not know something, you fear the worst and believe that your enemy is perhaps ahead of you. This drove the scientists in their effort to build the bomb as quickly as they could for the United States. 

Groves eventually assembled a team, a project that was called Alsos. It’s a Greek word that actually means “Grove,” like grove of trees. It was a scientific military mission with people who were going to be right at the front edge of the invasion, first of Italy and then after the Normandy invasion into Western Europe, who would try and find out really what was going on in the German project.

So they first have a mission to Italy. Of course, Italy is an ally of Germany. Perhaps Germany, if they were working on the bomb, recruited Italian scientists. But when some of these Alsos agents got to Rome and talked to Italian scientists, they didn’t see that very much was going on. But still, that didn’t satisfy Groves. With Vannevar Bush and other scientists, they assembled a larger team that lands in Normandy in August of 1944, and they begin to be with the troops as they go through France.

By September, October, and November, as they push towards the German line around Strasbourg, it’s becoming evident, finally, with capturing real German scientists now who knew something, that the Germans really don’t have much of a bomb project at all. But it’s only in about November 1944 that Groves finally is satisfied that the German project is not of any magnitude that’s going to threaten the United States. He keeps pushing on with the Alsos team as they invade Germany, on into the early months of 1945. Finally in April and May they’re rounding up the major figures in the German program, such as it was.

In early May, they get the crown jewel of Werner Heisenberg, who is captured. Groves has ten of the top scientists under his control. The war is over now in May, early May, and Groves decides to take these ten to a safe house in England called Farm Hall. About July 1, they are interned in this country house outside of Cambridge. Unbeknownst to them, Groves has the place bugged with microphones. He wants to listen in on these conversations that the German scientists are having among themselves to discover more about what they may or may not have been doing.

So from July 1945 until the end of the year, for six months, their conversations are recorded. These tapes only recently became public after about fifty years. It’s still controversial, but pretty much decided, I think, that the Germans just did not know how to make a bomb. They just had not thought through some of the things in enough detail, and not pushed hard enough to see how it could be done. I think these tapes show that to be the case.

When they learn on August 6 that the United States had dropped a bomb on Hiroshima, Heisenberg and the rest of the scientists are in utter disbelief. “How could it be,” they say to themselves, “when you would need so much highly enriched uranium?” They had not thought through the fact that actually you don’t need that much, and thus they were surprised. But after they knew it was done, then Heisenberg went back to his pad and pencil and recalculated and, sure enough, it could be done.

But the fear of the German bomb program was a driver from beginning until end for many, many of the people involved in the Manhattan Project.

The Manhattan Project sort of stands still today as a monumental effort to get a project done, to get a goal done in a short period of time. Having written a biography of General Groves, I put much of the responsibility on his effort for mobilizing industry, the military, science, and universities, to get the job done.

There are basically three pieces to the Manhattan Project, in terms of sites. There is Oak Ridge, where the uranium enrichment took place. There is the laboratory in Los Alamos, where the bomb was to be designed and assembled. And there is Hanford, where the plutonium was going to be produced.

Groves knew at the very outset that the pacing item of all of this was when there would be enough material produced for a bomb, then the bomb would be ready and soon after the bomb would be used. What strikes me as an absolutely amazing coincidence is that the two types of material—the highly enriched uranium that had to be produced at Oak Ridge and the plutonium which came out of the reactors at Hanford—were both done, or enough of it was done, for each type of bomb, two different designs, at approximately the same time. It seems rather remarkable to me, that this turned out to be the case. It could have turned out quite differently.

 If the plutonium at Hanford had been delayed for one reason or another—perhaps those reactors were poorly designed or there had been an accident or something—the plutonium would not have been ready by the middle of 1945. Or at Oak Ridge, if those factories, each having their own special features to them, if the highly enriched uranium had not be done when it was, the bombs would not have been ready in the middle of 1945. So I have always found it to be a rather remarkable coincidence that both of them were done at approximately the same time. I think, though, that the reason that it was done at approximately the same time was through the intervention of General Groves, who drove everyone to their limit to get it done.

If we look at Hanford, it goes through, of course, several phases: after choosing the site in the beginning of ’43, we have a vast construction effort to build the three piles, the chemical re-processing and all of the facilities that go with it. Once those are done, now it’s time to operate the plants and to operate them in a fashion to get as much plutonium as quickly as possible. Here you really see Groves’ hand in getting the production done.

When he learns that the plants are now about ready to begin operation—this is in the fall of ’44— he contacts the DuPont people and says, “Well, what are your schedules here? How much can you produce? Over what period of time will you have enough ready?” They come back with a schedule that shows there won’t be really enough until late ’45. This is unacceptable to General Groves. He says, “No, we need it faster. We need to speed up the process. What can you do to speed up the process?”

Basically there are three things you can do to produce plutonium more quickly in a reactor. You can turn the reactor above its limit. These were 250 megawatt reactors, so you could turn it up to 260 or 270 or 280. You could operate it at a higher level. You could leave the uranium rods in there for a shorter period of time, and push them out the back more quickly. That’s the second way to speed up plutonium production. The third way is to leave them in the cooling pools for a shorter period of time. Basically, Groves tells the DuPont engineers and executives, “This is what we’re going to do. We’re going to speed up the production to the limit.” And this becomes known as the speed-up project. They accelerate the production of plutonium.

Finally, Groves is satisfied that they will have approximately six kilograms, which is the key amount they need for a test bomb, by early July 1945. Then they will have another six kilograms a few weeks later, which will become the amount for the Nagasaki bomb. With those schedules in hand, Groves keeps the pressure on, and those reactors are going full tilt. The uranium is being pushed early. The very hot rods are coming out of the cooling ponds more quickly.

Plutonium is—in tiny amounts, in just little kilogram amounts—being assembled and taken to Los Alamos. Beginning in February, the first smidgen goes to Los Alamo. Then in March, April, and May, convoys, Army convoys, literally are taking little bottles of plutonium from Hanford, Washington to Los Alamos, New Mexico.

The way they are taken is perfectly representative of General Groves’ penchant for secrecy and compartmentalization. A convoy leaves Hanford—they used Army ambulances—and they put these little beakers of plutonium inside special boxes. They had an armed convoy with lead vehicles, front and rear, with Army couriers with rifles and everything.

But the people in the convoy didn’t know what they were transporting. They were told to go to Fort Douglas, which is outside of Salt Lake City, to meet another convoy, a light convoy, which had come from Los Alamos. At Fort Douglas, the switch was made, and the boxes containing the beakers of plutonium were put into the other convoy that had come from Los Alamos, and they turned around and went back to Los Alamos.

No one who was involved in the convoy knew what they were transporting, and the ones that had left Washington didn’t know the destination of where it was to go. The ones from Los Alamos didn’t know where it had come from. But this was just representative of General Groves’ obsession with secrecy and compartmentalization, which went even to transporting plutonium in these months of the spring of 1945.

Kelly: You described the six kilograms for the Trinity device and six that would be ready for Nagasaki. How much more material was there?

Norris: After the schedule had been set for first the test device, which would be the Trinity explosion in July 16, 1945, and then an equal amount for the bomb that will be dropped on Nagasaki, they are able to schedule amounts for subsequent bombs if needed. If there had been a third bomb—Hiroshima bomb being the first bomb, Nagasaki being the second bomb—if there had been a requirement for a third bomb, it would have been ready about August 17 or 18. There was enough material for a next bomb then.

By the end of 1945, there would have been enough for about twenty bombs. Groves had them lined up to the end of the year, if need be. There would be a bomb about every ten days after they got going. By this time, all three piles or reactors are going. They are able to schedule things fairly effectively. We are beginning the process of large numbers of bombs that would be ready.

Some people have raised the issue that perhaps the scale of the Manhattan Project, this vast enterprise here, was made ready for the Cold War that was to come in the race with the Russians, but I really don’t buy that. I think, looking at the Manhattan Project and the decisions that were made, it could have even been bigger at the time. There were going to be six reactors, for example, at Hanford. Three got built. There were going to be six chemical separation plants to go with those six reactors, and we end up with three, one of which isn’t used.

But there was really just one goal in General Groves’ mind, and that was to get a bomb as quickly as possible to have some impact in the war. And that’s what happened. He was not concerned about what was going to come afterwards. The fact of the matter is that many of those facilities do get used for sometimes decades after the war, to produce unenriched uranium and plutonium for the Cold War arsenal of the United States. But that was not in the plan to begin with, I’m quite convinced. The immediate goal was to end the war as quickly as possible using this new weapon.

Kelly: Why did they build them so substantially? It was just the radioactivity?

Norris: Yes, I think so.

Kelly: They didn’t under-build anything?

Norris: No, they didn’t under-build. That’s for sure.

Kelly: They demolished Hanford very quickly.

Norris: Well, of course, the building of Hanford required the peak work force in June 1944 with close to 50,000 people there involved in building all these vast things. The chemical processing plant was 800 feet long, and the scale of everything was enormous. But once they were built, there was no reason to have tens of thousands of workers there, and they were let go. The temporary camp that they occupied was demolished and taken down, but of course, the other facilities were maintained at Richland and so on. Those were semi-permanent for the people who would be operating the plants, the DuPont executives, the Army engineers, and others who carried on with operating the plants. Those facilities still exist, and turned into towns themselves that lasted through the Cold War.

Kelly: Do you have things you would like to add?

Norris: Many people point to the Manhattan Project as a kind of example of what America can do when it puts its mind to it. So it was this very successful effort at mobilizing the resources of the country, industry, science, the military and government, and then focus it on a goal that was achieved in the amazing short period of time of a little over 1,000 days, about three years.

People ask, “Well, why can’t we do that again to solve certain problems? Was the Manhattan Project a unique example of this American can-do spirit, or can it be recreated?” I have come to the conclusion that I think it’s really unique. The circumstances were such during the war that it just can’t be replicated again today. It was done in great secrecy in the midst of a war, which was one that really was for civilization itself. If fascism were to win, it would have been the end of our society as we have known it. So the stakes were incredibly high.

People’s commitment to winning the war was at the highest level. Most of the people that    worked on the Manhattan Project had no idea what they were working on. They were told that it was for the war effort, and that satisfied them. Thus they didn’t question what it was that they were doing, but they knew that if they did it, the war would be over more quickly. These would be hard things to replicate in our modern, open society. Congress was not involved in any way, shape or form, other than appropriating the money for it, but only a few Congressmen knew what this project was. They had been told by Secretary Stimson and General Marshall that it was for the war effort and they shouldn’t inquire, and that was enough.

So I think the Manhattan Project is rather unique in the American experience here and it would be very difficult to recreate it, as much as we might like to be able to do these things again. Now, we can take parts of it and perhaps do it on a scale that is similar. But this grand effort—which was a two billion dollar plus effort at the time—if you transpose two billion dollars into today’s dollars, it’s probably about forty billion dollars, about twenty times as big today. Can we imagine a forty billion dollar effort concentrated today on doing something and getting it done as quickly as it was then? It is hard to think of what that might be.

In the end, I think the Manhattan Project will have to stand as a testament to very creative people, under great pressure, accomplishing a goal in an amazingly short period of time and helping to end a terrible war.

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