Nuclear Museum Logo
Nuclear Museum Logo

National Museum of Nuclear Science & History

Ernest Tremmel’s Interview

Manhattan Project Locations:

Ernest Tremmel was a civil engineer who worked on the Manhattan Project for the Army Corps of Engineers, as a purchasing officer. He went on to work for the Atomic Energy Commission (AEC) for many years and as a nuclear energy consultant. In this interview, Tremmel discusses the secrecy of the Manhattan Project and how he learned the goal of the project. He recalls interacting with General Leslie R. Groves, Admiral Hyman Rickover, and other AEC commissioners as well as directors of energy companies. Tremmel explains what made this period, and the quest to build nuclear reactors, so exciting. He also remembers witnessing a nuclear bomb test after the war.

Date of Interview:
August 9, 2002
Location of the Interview:


Ernest Tremmel: I’m Ernie Tremmel. 

I graduated from the University of Wisconsin in civil engineering, and I went to work for the Corps of Engineers in St. Louis. One of my bosses was a Captain Powell who, after I was in St. Louis two years, got transferred to a secret project he was going to work on called the Manhattan Project Corps of Engineers.  

He asked me if I’d like to go to Delaware with him, so I went to Delaware. After I was there about a year and a half, one of the fellows I worked with, we were having a beer one night. He says, “I figured out what we were working on.” He had with him some comics that had portrayed this big bomb. He says, “This is what we’re working on.” 

Being a young boy and very honest, I went to my boss and I said, “We know what we’re working on.” 

He says, “The hell you do.” [Laughter]

I told him what it was and he says, “Oh, my God.” He brought us all in and told us, “All right, you have got to keep this very secret. Do not talk about it or anything.” 

I was there about a year, and they said, “How would you like to go to California?”  

I said, “I guess that would be all right, because I have an aunt out there.”

They sent me to Washington, DC, and I found out that I was assigned to General [Leslie] Groves’ office for two weeks with two other young engineers, one from Purdue and one from Ohio, to work there to be sent out to work on this project. 

I always remember, General Groves was a very friendly person. I always felt at ease with him, even though we were young students. He would talk to us in the morning and say, “Hi, how are you doing?” I was also disappointed that he was so overweight. I thought, “Here’s an important man in the service, and you would think he would worry about how he looked physically, too,” but I guess he was so absorbed in what he was doing. 

Then they gave me a telephone number, and said, “You are finally going to go to California,” after I had been there two weeks. “We will tell you where you are going to work when you get to Los Angeles. Call this telephone number.” 

I had just gotten married. I went to Wilmington and I got married, so my wife was with me. We went to California, and at that time, there was a very bad housing shortage. Fortunately, she had an aunt, and her aunt took us in. I called the number, and they told me, “You are working at an office called Calexico Engineering Company.” 

Calexico Engineering Company was a company that had offices in Los Angeles, Chicago, and New York. It was set up to purchase parts for the research people on the atomic bomb at Los Alamos. Everything would be shipped to Los Angeles, and then from Los Angeles it would be sent out by the Navajo freight train down to New Mexico, so it was a cover-up operation. 

We were in Los Angeles. I worked there about two years, and one night after I had been there not quite two years, some people came up from New Mexico. They would come back and forth all the time. Some of the people that worked down there, they would bring them to Los Angeles to help procure right specs and things. We went out and had a few beers. This guy that had had too many says, “I can tell you guys something that you don’t know that I know.”  

We said, “What’s that?” 

He said, “They are going to explode an atomic bomb in about ten days.” 

We all laughed at him and thought, “This guy has had too much to drink.” Sure enough, that was when the first bomb was exploded down in New Mexico. That was a very interesting story. 

The other thing that was interesting out there is that this operation went on for a few more years before the Atomic Energy Act was passed. That was after the Japan bombs, and I don’t know whatever happened to the office. I ended up going to Chicago to work at Argonne National Lab. There I worked for about two years on all kinds of nuclear energy. 

I have to tell this one story about while I was in Chicago—no, it was not in Chicago. I worked there awhile, and then from Chicago went to Cincinnati, where I was hired by General Electric to develop a nuclear propelled airplane. They were using a water reactor. I worked there two years, and then I became the manager up in Connecticut to develop a liquid metal reactor to fly an airplane. 

From there, I transferred to Washington, DC. At the time I was there—I’m trying to remember who the guy was that was director—McCone. Chairman [John] McCone had been head of the Kaiser outfit that built all the ships that loaded and unloaded the tanks when they raided Europe. He was the chairman.

I worked for Commissioner [John] Floberg. There were five commissioners. McCone says, “I’m not going to be around here but maybe only a couple years, so you all get out there. I want to build the first nuclear power plant in this country.” 

I put together some charts to show him it was like fifteen years away, before you would have the first nuclear power plant. Things we had to learn, we had to go through licensing. And he says, “Who put this silly report together? I’m not waiting fifteen years.” 

My boss was a lawyer, Floberg, and he says, “That’s the way it is, Mr. McCone.” 

He [McCone] finally realized he was not going to see a nuclear power plant built while he was Chairman of the Atomic Energy Commission.  

They sent me out. My boss asked me, “Would you like to see a nuclear explosion?” 

I said, “Yes.” They sent me out to Los Alamos to watch one of the tests. That was very interesting because we were on a hill and the bomb was way down, a long ways away. Far enough away you could hardly see what they were doing. 

About that time, all the bad luck, I had to go to the bathroom. All they had out there was one of these outhouses. I went in there. While I was in there, I heard this big bomb—I mean, this big noise go off. I thought, “Oh, my God, I came all the way out here, and I missed the explosion!” 

I ran out with my pants hanging half down, and they all were laughing. They said, “No, that’s some preliminary testing they do to see which way the wind is blowing.” I didn’t miss the bomb. [Laughter]

When that thing exploded, I could not get over it. You saw the flash, but you just sat there and all of the sudden, a heat wave came. You could see it blowing grass down, you know. Then it hit us. Boy, that was hot even as far as we were away. That was impressive. 

Most of my career was spent in Washington where Jim Schlesinger was Chairman [of the Atomic Energy Commission] for a while. I am trying to remember the lady now, Dixy Lee Ray. Dixy Lee Ray was funny because she was a little on the heavy side. She always had her dogs. Even when you went in her office, her two dogs, sometimes she had three, were sitting on the Davenport. She had to make one of them get off so you could sit down. The first time I met her she was at a reception, and she had this beautiful maroon coat. It looked so nice. I said, “Chairman, that coat is just beautiful that you have on.” 

She said, “What’s your name?” 

I said, “Ernie.” 

She says, “Ernie, I want to tell you a secret. I had to buy this in a man’s store. I can’t find any women’s clothes to fit me.” [Laughter] I thought that was kind of funny. 

While I was there, fortunately I had a chance to work on almost every kind of nuclear reactor there is, you know, gas-cooled, natural and boiling water, pressurized water. I was just very lucky I was able to do that. While I was there, I ended up in a job, which was to show utilities how to build nuclear plants. 

We had a public relations office, but I was in a separate office. They could come and ask me what the economics were, and if they could build one on their system. I remember when they built the reactor [Trojan Nuclear Power Plant] out in Portland. The man that became president of Portland [General Electric] was the man that came in. Chairman [Glenn] Seaborg sent me out there with him to look at the site and give them a briefing on nuclear power, how it worked, and so forth. It was pretty exciting. I was very lucky. 

When I was out there, I always remember that Oregon has these berries. I guess they call them boysenberries. They have them in Los Angeles, too. They are so delicious. On the site where they built this reactor, there were these berries. We all ate so many we were sick that night. [Laughter] I always remember that. The other thing I remember about going out to Oregon is the delicious salmon, poached. Have you ever had poached salmon? Poached salmon is just delicious. That was a great trip. 

Then I also remember going down to Duke Power. The guy, Mr. Lee, who became the president of Duke Power, was, at the time, a young engineer. He was my slide projector assistant to run the slides that I had to show. Bill Lee, and eventually he became president. He died a few years ago of a heart attack.

I also was sent down to Florida to meet with McGregor Smith of Florida Power and Light. At that time, we built Turkey Point. We built two reactors that were the cheapest reactors that were ever built in this country. 

It was kind of interesting, because McGregor Smith took Chairman Seaborg and I out for a ride in their dune buggy, those buggies they had, so we could see all the marsh land there. That was very interesting. 

At that time, its chairman, McGregor Smith, was a very interesting man. He said, “Ernie, I want you to stay overnight if you can. I’ve got to learn more about SWUs.” SWU is a name for a degree of enrichment of uranium. He says, “I been hearing all about those SWUs. Tonight you are going to come over to my house for dinner, and I would appreciate it if you would spend an hour or two with me explaining SWUs and what they are about.” So I did that. It was kind of interesting. 

He was a character. He came from Missouri. He took me out to get me a beer. This one tavern he went to, they had a special chair in the corner with a bell above it, and that was his chair. He could ring the bell when he was ready for more drinks. It was really very exciting. 

One of the exciting things was trying to build a reactor to build a nuclear airplane. It turned out to be a very tough job, because of the weight. The first design they had, if you and I are going to go to the airplane, you would have a little pathway lined up with lead shields on both sides. You would walk between them, so you would be shielded from the radiation from the plane and go inside the plane through a heavily shielded door. I think eventually they could have had an airplane, and they would have been able to design it, but in the meantime the Polaris missile and the submarine were successful, and they decided they didn’t need two systems. One was a system that would do it. 

The other interesting thing I feel very lucky about is that when I worked for Commissioner Floberg, Admiral [Hyman] Rickover was in his prime time. He was always inviting the commissioners out to see the submarine. So he invited Commissioner Floberg, and because I was an assistant, I was invited, too, to go have dinner on the Nautilus in Connecticut on the bay. I flew up separately because Mr. Floberg had to come up later. I flew up a little ahead of time. 

Who meets me at the airport but Admiral Rickover, and he paid my taxi fare to the place where we had dinner that night under the ocean. A lot of people did not believe it, because he was known to be pretty, pretty tight. They could not believe that he paid my taxi fare. But he was a very exciting guy. 

The other incident I had with him that was fun was when we had the campaign when Glenn Seaborg was there. He made me head of the group to sell war bonds. We always had a quota to meet, and the problem we had, the naval reactor people under Rickover never would buy any war bonds. They always pulled us down, because other people would buy them and they wouldn’t. Glenn Seaborg said, “See what you can do with the Admiral. See if you can’t talk him into getting some people to buy some of these bonds.” 

I called him, and he said, “Well, it is such a great cause. I am so sympathetic. I wish I could get all my people to buy those bonds. But my people are enlisted men, and they don’t make enough money to buy savings bonds.” He says, “You’re welcome—why don’t you come? I’ll call a meeting, and you come and try and sell them.” 

I said, “Admiral, it’s very easy. All you have to do is tell them you want them each to buy a bond, and that’s it.” 

He said, “Oh, Ernie, you wouldn’t want me to do that. I would never coerce anybody.” [Laughter] He gave me what I call “the glad-hand treatment.” They didn’t buy any bonds. I didn’t do very well. 

The other guy that was a commissioner at the time was Tommy Thompson from M.I.T., and he was a brilliant young scientist. I got to know him pretty well. 

I asked him to buy some savings bonds, and Tommy says, “I really believe in them, but I’m having trouble existing already on the salary. Even though I’m a commissioner, with my family, I don’t make a lot of money, and I don’t think I have enough right now. In a year or so, I’m hoping to be able to start buying some bonds for my children.”

Tommy went out to Nevada. While he was out there, he and another commissioner took a trip looking over the Hoover Dam there, and their helicopter crashed and sunk, and all of them died. By the time they got their bodies out, they were all dead. My best friend, who was his assistant, was along and excited about going, and he drowned, also. It was a terrible thing. We lost a commissioner that way. I always remember that.

A lot of things I told you were a lot of fun for me. I always considered myself so fortunate to have lived when I did and doing all those things. Every day was exciting. 

I remember we went to Japan right after the war. I was with Chairman McCone, Dr. [Robert E.] Wilson, and the President of Westinghouse. We had a bridge game. I was the fourth. All these guys were great bridge players. Firstly, my partner was Dr. Wilson, who was a brain. I knew if he gave me a dirty look that I shouldn’t do what I was about to bid or something. 

We did all right. We were flying to Hawaii. It was very interesting, playing bridge with the Chairman of the Atomic Energy Commission and the President of Westinghouse. [Laughter] I was in pretty good company. 

When we got to Hawaii, we left early in the morning to go to Japan. When we got there that night, we went out to have a few drinks, but I didn’t wake up. They woke me up in the morning. It was time to catch the plane. I didn’t get to go to church or anything, I slept so long. 

It was working for the Atomic Energy Commission that was so exciting, and back in those days when I worked in Los Angeles, we had a top priority. There was only one priority, one program in the United States during the war that had a higher priority than the atomic bomb. That was the program to build these big tankers that unloaded the troops that landed to invade. Mr. McCone was head of that company that made those. They had a higher priority than us. 

But next to that, I would pick up the phone and call Stanley Screwdriver and ask for the president. I would say, “Give my priority number, right through to him, right away.” I said, “We need 100 of this kind of screwdriver shipped to Los Alamos immediately.” That was it. We had such a high priority. It was really fantastic. I forgot to tell you, part of the time we were in there they were training us to tell us what the priority system is and where we fit in and what we should help the Los Angeles office do. We were sent to different offices to help them know what the priority system was. So it was very, very exciting. That is about a summary, unless you’ve got some questions?

Kelly: Well, I appreciate you sharing all of this. It is great. I am trying to think of anything else you might want to share that has to do with the Manhattan Project?

Tremmel: I can’t think of a lot, except I know that another interesting part of the Manhattan Project was a couple of these fellas came to Los Angeles. I went with them out to this little guy that had an electronics shop in the back of his home. 

The reason we went there was that they were at that time studying to explode the bomb with a gun, but this was an implosion to surround the bomb with these, like, firecrackers that go off and cause an implosion. This company was the only company in the United States they could find that had any experience making those particular type of firecrackers or things that would explode. 

It was interesting to me because when they decided he could do it, they were assigned security guys to watch that day and night so nobody could know what he was doing or get at it. He was successful in making some of the explosions that they wrapped around the bomb to make it, call it implosion. 

That was impressive, how far we would go, send people there and they would take over this guy’s place and pay him. He got paid well. But we made him do nothing but that for us. It was interesting because it was very tough to find a place to live in Los Angeles. Fortunately my wife’s aunt was married to a guy we call Smiling Tom. Tom ran a used car business, and he only handled Lincolns and Cadillacs. Whenever we needed a car, we either had a Lincoln or a Cadillac. That was pretty nice. He was Irish, and even though he had never been to Notre Dame, he gave them so much money that they made him an honor student, or gave him an honor degree. 

Those are all little things that happened during the war that were very exciting to me. To this day, I am still working on nuclear stuff now. I am still doing part-time work. I have been working hard on Yucca Mountain and some other things we are working on is [inaudible] accelerators. If we can get an accelerator that can zap a nuclear waste and neutralize the nuclear waste so it will only have a 200 or 300-year half-life instead of a million years, you can do that. What you do is separate the plutonium and uranium out, use those over, and then your accelerator could zap all that bad stuff like cesium. It would neutralize it so that you could start, and it would decay within two or three hundred years instead of a million. 

That shows what they are working on now. It is getting very exciting. I tell people, we have to send the stuff to Yucca Mountain, but you do not want to bury it because our grandchildren are going to mine that stuff. It is going to be very valuable to them some day, when there is a shortage of water and electricity. 

That is some of the things I am working on now, part-time. I go to Congress as a technical advisor. That is a lot of fun, because our two senators from Wisconsin are very good friends of mine, [Senator Herbert] Kohl and [Senator Russ] Feingold, and we have a couple Congressmen from Wisconsin. People still, if you tell them about nuclear energy and they understand it, then they understand why we need it. 

Copyright 2016 The Atomic Heritage Foundation. This transcript may not be quoted, reproduced, or redistributed in whole or in part by any means except with the written permission of the Atomic Heritage Foundation.