The Manhattan Project

In partnership with the National Museum of Nuclear Science & HistoryNational Museum of Nuclear Science & History

Harold Hasenfus' Interview

Printer-friendly version

Harold Hasenfus' Interview

Harold Hasenfus was part of the Special Engineer Detachment during the Manhattan Project and worked at the University of Chicago's Metallurgical Laboratory and at the gaseous diffusion plant in Oak Ridge. While at Chicago, Hasenfus worked at a pilot plant that was constructed to assist in the design of the B Reactor in Hanford for the production of plutonium. Hasenfus attributes the success of the Manhattan Project to General Groves, who he described as a "tremendously dynamic individual." When Hasenfus returned to Stagg Field at the University of Chicago years later, he was surprised to find "a big open field with a beautiful green lawn and a marker about the size of a desk to show that the first sustained chain reaction had taken place there."
Manhattan Project Location(s): 
Date of Interview: 
April 27, 2002
Location of the Interview: 

I was a member of two Special Engineer Detachments: I worked at the University of Chicago at the Metallurgical Laboratory and I also worked in Oak Ridge Plant, conceived and designed by Philip Abelson, who is probably here today. I lived in the barracks area when I was at Oak Ridge and I lived in an apartment with three other soldiers when I was in Chicago.

I brought something away from the project that many people did not have opportunity to do, I think. We worked very hard. I went to Oak Ridge first and then I was immediately transferred to Chicago. When I returned to Oak Ridge, that was such a high priority thing that we worked on that project seven days a week. At the end of that week, we would shift to another period of the day when we worked and worked another seven days. Then we would change to the third shift and work another seven days. At the end of that period we got one day off. So we worked very hard. But when I was in Chicago, I met the woman who became my wife and the mother of my four children. So I was very happy to come away with that. 

When I went to Chicago, I worked in West Stands where Fermi had conducted the first chain reaction and built the first pile—what we call reactors now. Next door to the squash courts where he built the pile, there were four four-wall handball courts and in those courts there had been constructed, and in operation when I got there, a pilot plant that was used to assist in the design and solution to problems that were experienced at the large plant in Hanford, Washington for the production of plutonium. This pilot plant was built to get small samples of plutonium, to separate them from the fission products and solve the problems that they were having at the big plant in Washington. 

That plant was run by the Du Pont Corporation. All the people there were du Pont engineers, except toward the end when I left unexpectedly, I didn’t know I was going to leave, I began to notice we were getting a lot of young PhDs who I imagine were not employees of Du Pont but were instead employees of the University of Chicago. 

I worked there for about 9 months and I also worked at Oak Ridge for about 9 months. I went home for Christmas time from Chicago, when I came back my three roommates were gone. All the other soldiers were gone. Turns out they were all sent to Oak Ridge to start up a new plant, a thermal diffusion plant, the concept of which originated with Phillip Abelson from the Naval Research Laboratory. That was a tough job getting that thing started up and we did work very very hard. 

While I was there living in the barracks, VE day occurred and I had always wanted to go to Officer Candidate School so I applied to go to Officer Candidate school from there. I was an engineer soldier; the board was all engineer officers. They asked me where I would like to go and I had been, as an ordinance soldier, at Aberdeen Proving Grounds. I felt that my chances of success would be much better if I returned to Aberdeen. So they wrote away for a quota-1 for me to go to Ordinance OCS and in very quick time they got an answer which was yes and that’s how I left the project.

While I was at OCS, VJ day occurred. We were so busy at OCS that it wasn’t until the following weekend that I knew the bomb had been dropped. Of course, the bomb at Hiroshima used the product from our plant with the product of other capabilities of Oak Ridge. The company [I worked for] was called the Fercleve—The Ferguson Construction Company of Cleveland. The codename was Fercleve. What I did at Fercleve resulted in some product that actually got into that first bomb. 

I would say that [the atomic bomb] is a terrible, terrible weapon and what I think is required is to take all steps necessary never to have to use this weapon again under any circumstances even for these smaller munitions that the army has to use in the battlefield. I think that’s a catastrophe. 

The reason for the success of the project was General Groves. He was a tremendously dynamic individual. I met him on one occasion when he came to Oak Ridge for morale purposes, but as busy as he was, he was immaculate—there was not a single speck of dust on his uniform, on his shoes, everything was in place. He was a very impressive man. I was so impressed as a matter of fact that I went to go see his grave in Arlington Cemetery. I had to go back to the administrator of the cemetery three times to find it because I thought being such a distinguished man he would have a prominent grave there. Well it turns out that after he was buried a shrub began to grow in the vicinity of his stone and this shrub now completely dominates so that unless you bend down and look underneath it you can not find the stone where the General is buried. Not many people know that General Groves was the design engineer of the Pentagon building. And so now as he rests in peace on this hill he can overlook this tremendous job that he did locally in Arlington.

On a subsequent visit back to Chicago after my children were born, we wanted to show them where we had lived and as you know Stagg Field was the football stadium at the University of Chicago. It was a very unusual stadium because there were space limitations; the only place there were any seats were at the west end of the field. There were none along the sidelines or at the far end of the field; they had built a field house over there. But at the west end they had seats, so the people would watch the game over the goal posts and that was West Stands. 

When we went back with my children there was nothing there. It was just a great big open field with a beautiful green lawn and a marker about the size of that desk to show that the first sustained chain-reaction in the world had taken place there. And it turns out that whole area of private homes had also been taken out—nothing but green grass. It was very, very surprising to see.