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Herman Snyder’s Interview

Manhattan Project Locations:

Herman Snyder worked on the Manhattan Project at Oak Ridge as a soldier in the Special Engineer Detachment. He worked at the K-25 Plant for many years, and later at the Y-12 Plant. He discusses the many innovations that caused K-25 to run so smoothly and to be built so quickly. Snyder also reminisces about the sense of community at Oak Ridge, and recalls having to scrounge a pass to get his new bride through the gates into Oak Ridge.

Date of Interview:
June 18, 2005
Location of the Interview:

Transcript:

Herman Snyder: My name is Herman Snyder, H-E-R-M-AN S-N-Y-D-E-R. 

Cindy Kelly: Great, good job. All right, now, maybe we can pick up the thread of that story. If you can tell us your experience, and compress it a little bit because I want to spend most of the time talking about your experience here at Oak Ridge and K-25. But I do like the idea that you were, you know, shoved away, that you were in this place with all these tests, and, you know, provocative. That was good. I think that’s interesting.

Snyder: Okay. I was in the Army, in the infantry section of the Army. I had an engineering degree. I got special orders to report to Ohio State University, wondering why in the world I was going back to college. I had my degree. I wanted to get into action somewhere.

There, there were a lot of interviews, a lot of tests, some very provocative tests boring into my personal life. Didn’t know why we were there; nobody knew. But we found out, ultimately, that we were being screened by the Army for potential assignment to the Manhattan District, the Corps of Engineers. All these fellows I was with up there, small group, kind of aside from the rest of the student body, were engineers or scientists, some specialized training in some technical profession.  

We spent most of the time in interviews and tests. Eventually I was told, along with another group of fellows, to board a Pullman car, Army Pullman car, which happened to be on the siding right there on the campus. And we were going somewhere else. Nobody told us where. 

We got on there and we woke up the next morning in the L&N railroad yard in Knoxville, Tennessee. It became part of the grounds for the 1982 World’s Fair, incidentally. We got on an Army bus there, not knowing where we were going, went through the mountainous area of Tennessee, not knowing what the destination was. 

Eventually wound up at what looked like an Army camp. It was kind of an Army camp. It had a big sign out front: “Clinton Engineer Works.” We went in there finally and there we learned we were assigned to the Manhattan District, Corps of Engineers, U.S. Army, in a Special Engineer Detachment.  

After a lot of security orientation, we wound up in the barracks area. They were comfortable. It was sure a different life for the Army. We had hired people taking care of the latrines, and keeping the barracks clean, a cafeteria right next door. No KP [kitchen patrol] duty, no latrine duty, none of that stuff.

Turns out we just lived in that barracks area but our assignment was to go to work for one of the contractors in the area. And we were accountable to them for our performance and everything. If there was any misconduct, then we went back to the care of the Army, but otherwise, we just worked and we lived at the barracks area. And I must say, for the most part everybody worked very hard.

It was an unusual type of assignment. It was an opportunity. It was something new. It was enormous in scope. I don’t think the country could do it today. We’d get lost in paperwork before we ever poured any concrete.

But we had a town that was being built. We had installations that were being built, manufacturing installations, research installations. The town—it was growing rapidly, thousands of people. 

When we got here, we knew Army had something to do with it because all the architecture and general atmosphere was Army. But there wasn’t anything military. No parade grounds, no tanks, nothing like that.

I was assigned to work with Union Carbide at the K-25 plant. I worked as their other engineering employees worked. I was just one of their employees in essence, but I was in uniform all the time. The plant was well under way construction-wise and was just reaching the start-up period at that time.

So I got in on the ground floor, initially just helping to get the system prepared for operation. Now, at this time nobody had advised me nor any of the fellows I worked with really what we were doing, or why we were doing it, or what the objective was. In engineering function, we had to have access to plant drawings, process systems, manuals for all equipment and instrumentation. It didn’t take long to understand what we were doing, but the why just wasn’t answered, wasn’t discussed.

Even in the barracks areas, the guys didn’t say much, except a good day or a bad day, or something special and exciting. Many of us just worked day and night ‘til we got tired. Buses were running all the time. You would take a bus back to the barrack, get some sleep, good meal, back to the plant. It was exciting. It wasn’t work, and it wasn’t military, but it was exciting professionally. 

Eventually, we were ready to start up the plant. Nobody was sure this plant would produce a thing, and they had already spent millions building it and researching it. There wasn’t a lot of time for research. They had to research it while they were building it. It just had to go. This General Groves, he was a pusher. He kept everybody on their toes and moving with a lot of assumptions that it’ll work, it’ll work, it’ll work.  

Well, the Y-12 plant was already in operation and it was working. Production was very small though compared to what we anticipated at K-25. We got ours started and it gave indication that it could work. In fact, it worked beautifully.

We had a lot of women serving as operators that had to be trained, did a fine job.  Maintenance people, of course, had to be trained. The operation—everything was secret. It’s not all secret now, but that plant operated at a vacuum. It had to be airtight. We couldn’t tolerate any air leaking into that process with uranium hexafluoride. It would have plugged everything up quick.

We couldn’t stand for the uranium hexafluoride to get hot either, so it was really sealed up well. And that was the amazing part. Well, the two amazing parts of the engineering feat, there was building a plant like that and the barrier that was used for the separation of the 235 and the 238 isotopes of uranium. As the plant was operating, more and more was put into operation. And performance continued.

Well, we had our mishaps. We had our own power plant to generate electricity. We used, at that time, something like a third of the total electricity in the state of Tennessee. There were a lot of pumps and a lot of motors driving this gas through that plant all the time.

The Army, or let’s say the government, particularly the Army, decided that we were doing well and that we could do better if we built more plants. So there was promptly a duplicate type of system built, called the K-27 plant. As time went on, there was an assumption that there would be a great demand for nuclear power.

By the way, while I was working—not knowing why—I, for one, knew that we were getting some kind of concentrated energy here. What were they going to do with it? I saw visions of driving battleships endlessly without refueling, maybe even airplanes and long-range opportunity with nuclear energy power. Never thought of a bomb.

When they dropped that thing in 1945, I was as shocked and gleeful as anybody else to think that we were bringing this war to an end. But then in the future, of course, a lot of our work was to make more bombs, and hopefully a peaceful application to the benefit of all.

Unfortunately, this country suffered from nuclear phobia of some kind. Everybody developed, particularly our politicians, a resistance to anything involving nuclear energy. Of course, the bombs were very dramatically deadly. But radiation isn’t that much of a problem; you can handle it. I worry more about gasoline trucks running through town at sixty miles an hour than I ever worried about radiation accidents.

So, anyway, the nuclear industry didn’t develop as anticipated, at least not in the United States. And we did not become the world leaders in it because other countries went roaring ahead with it, like Japan and France and others. And today they get most of their power that way. I think the day’s coming when we will too, because everybody’s worrying about contamination of the atmosphere from steam plants and that sort of thing.   

Well, I’m just rolling on and on, and maybe you want to change the subject.

Kelly: No, no. This is great. Actually, we just finished doing a documentary on the work in Idaho to pursue peaceful uses of nuclear power.

Snyder: Well, this went so well that eventually the government has built more plants, here in Oak Ridge, a K-29, a K-31, a K-33, then a plant in Paducah, and then another plant in Portsmouth. Union Carbide figured they had enough with Paducah and Oak Ridge; they did not operate Portsmouth. Goodyear did that, but we did the design and led the construction work.

So it was quite a career. And we did such a good job we worked our way out of business. K-25 area was the first to be shut down. So I took a transfer over to the Y-12 Plant. Instead of making fuel, I joined making weapons. And my whole career then was in Oak Ridge. I retired and I’m still here. 

My wife came down while I was still in the Army. She went to work too because she had to, to get us decent housing, because I didn’t qualify. You know, the Army had housing for everybody but the Army. We both liked it here, like the people, like the countryside. We came from Pennsylvania. Liked the lakes, raised our kids up there on a boat on a lake. So we’re still here, so are our kids, our grandkids—I even have a great-grandchild now. All Tennesseans. 

Kelly: That’s good. That was very nice. I have a few things I want to see if I can get for this interview. You mentioned that there were, you know, extraordinary innovations that underlined the success of K-25. One was the barrier and was—you talked about the magnitude of the plant. Can you talk about something along those lines, of how much of an engineering feat that K-25 was, and how big it was? This is for a general audience, doesn’t know about K-25. You want to give them a sense for what a remarkable plant this was in so many respects.

Snyder: Well, let’s see. Sometime in the 1940s, when Roosevelt approved getting into a project directed toward an atomic bomb, and General Groves finally became the man in charge, they established a research operation in Columbia, Columbia University in New York, to develop this porous material that would be used as a barrier in a diffusion plant to separate these uranium isotopes. They worked hard and long on that. Then Kellex Corporation of New Jersey had the contract to design the facility. And what an amazing job they did, of course in concert with Columbia as to the nature of equipment and the layout and all that sort of thing.

You know, it’s still kind of unbelievable this could all be accomplished in such a short period of time. Of course, Groves had the authority that money was no object, your priority was number one, and he was a persuasive individual that got industry and everybody to do what he thought was needed.

At the same time, out in California, at Berkeley, he had them working on the separation process that was installed at Y-12, a spectrometer type of operation and separation using magnets that deflect atoms of different weight. Same experience over there; they were building while still experimenting. 

When you think of all the valves and instrumentation in the K-25 Plant that had to be developed and be leak-tight, this was done, all this equipment was built, shipped in here—miles and miles of piping, copper tubing all over the place. In fact, we used up so much copper they had to use silver in the magnets over at Y-12.

You know, I have to keep thinking about security. Some of this process is still classified.

Snyder: Well, I’m looking at a diagram here that is representative of a few stages of the gaseous diffusion process. There were thousands of stages, but it was a recycling process. If you’re familiar with the distilling procedure, you have these distilling towers, where you separate materials using temperature, using weight, that sort of thing. And at different levels of the still, you can draw them off, whatever you’re looking for.

Here we had horizontal operation, but it was big. Lots of piping and valves and what we called converters, which are like cylinders that, in reality, looked like condensers because they were full of barrier tubes. 

The gas was processed as uranium hexafluoride. And it had its peculiarities about temperature to keep it gaseous, no moisture to keep it dry. It was a fluoride subject to change to other compounds depending upon contact with other metals or gases, so it had to be handled carefully. It was also toxic in the event of escape because it immediately, in moist air, changed to an oxide of uranium and hydrogen fluoride, which is very toxic. So everything was airtight.

We had a pump at each stage, a high pressure pump that would pump the UF6 into the converter with the object that half of this gas would go through it, through the barrier; the other half would just keep going. But, for the half that went through the barrier, there’d be an increase in the number of 235 atoms that went that route because of the rigid control of the little holes in the barrier. And they were minute.

Consequently, as you went from one stage to another, there was more 235 going upstream. Well, there was another pump sucking on the other side of the barrier to pull this stuff through. And that comprised a stage: two pumps and a converter. 

Aside from that, of course, the gas gets hot being pumped. There was cooling systems, elaborate instrumentation systems, so that, as operators, we knew what was going on, what the pressures were, what the temperatures were, and so on. And you just keep repeating this thing until eventually you get a stream that is more enriched in the 235 atom. 

And, like I said for the still, you can draw it off anyplace in the system for the amount of 235 that’s desired. For the weapon, they wanted it pretty rich, you know. The weapon depends on the 235, so the more the merrier. But there are a lot of other applications, particularly for reactors, where they want less enrichment.

So it was a long stream, a lot of pumps, miles and miles of it, but it did the job. We started out with uranium that has only seven-tenths of one percent 235 in it and the rest is 238. So the stuff going out the bottom is a load. It’s a lot of uranium. The stuff coming out the top is a lot less. The stuff going out of the bottom lines up in big ten-ton cylinders, many of which were still in a field out there at K-25 until recently, when they started shipping them out to get them out of Oak Ridge. They aren’t good for much of anything except lead sinkers. It’s heavy stuff. The product of the diffusion plant went out in small, little cylinders, could be carried in a suitcase. 

Kelly: How much was needed for the bomb? I think it’s about as big as a softball or something. 

Snyder: No. I’m not going to talk about that. 

Kelly: Okay, that’s fine.

Snyder: I’m retired for over twenty years. I don’t know what’s classified anymore and what isn’t.

Kelly: Yes, that’s true. It gets tricky. Can you put us physically inside the plant and describe what it’s like to walk down, let’s say, one of the withdrawal alleys? What do you see? How do you get from here to there? You can talk about bicycles or whatever.

Snyder: Well, the original K-25 plant had an operating floor, let’s call it the ground level floor, that contained the converters and the pumps and a pipe gallery overhead. All the essential valving, the instrumentation, copper tubing, went from all that equipment up through the next level floor to the operating level. So there was the operating equipment area, the pipe gallery, and then the operating floor.

On the operating floor, a lot of valves stuck through that floor. A lot of them were motor-operated and a lot of them were hand-operated, with big wheels. In the basement were transformers, providing all the power to these pumps and everything else in the building, including the lighting.

Ventilation: of course, the system generated a lot of heat so we had a lot of conventional fan ventilation, big ventilators up on the roof of the building. We also had coolers in the converters to cool the gas. We couldn’t put water in there for fear a cooler would spring a leak and put water in the system. That would ruin everything, not from a hazard standpoint. It would just plug up everything.

So we had a special coolant in the fluorine family, like the gas, and that was circulated through the converters and, in turn, circulated through water coolers in the basement. And the water was just recirculated through the whole plant in a bunch of cooling towers. People going by the plant would see all these plumes going up in the air. A lot of people thought, “That’s a lot of smoke and contamination coming out of that place.” It was water vapor, the heat from the water.

We used air for instrumentation so we had an air plant, dry air. The air had to be compressed, had to run through dryers, and then piped all over the place to feed every little instrument. The instrumentation was pneumatic. Had to have facilities for feeding the uranium hexafluoride into the plant, facilities for extracting the enriched uranium hexafluoride.

Every time we made changes in equipment, made repairs, we wound up with something that was contaminated with uranium. Now, the uranium itself isn’t that much of a concern. It’s an alpha emitter, but a sheet of paper will stop alpha radiation. It’s the beta and gamma radiation that one has to worry about, and that was not the major concern in our plant. It was a concern, but not a major concern.

However, this material, this uranium material did irradiate alpha and the material itself was toxic, so everything had to be decontaminated, repaired, ready for reuse, and that sort of thing. There were a lot of side operations to this stream of UF6 just running all the time. It was complex. As I said before, it was huge.

Most of the pictures of K-25 are that first “U”-shaped building. And that had these levels I’m talking about: a basement and an operations floor, a pipe gallery, and then an operating floor. We’d run around on that operating floor on bicycles. It was a big building. And in my particular job as an engineer, and later on as supervisor, was to get to a lot of places in a hurry. Not because we were always in trouble, but just to take care of things. We did it on bicycles.

When we got into newer designs, like the K-29, 31, 33, the equipment was larger. The pumps were much different. We learned a lot from K-25, so that the newer plants, like Paducah and then Portsmouth, had a lot more efficient equipment. Even ventilating and water systems and whatnot were more efficient.

But the K-25 plant worked. And it was just in somebody’s head and then eventually on paper and then there it was, and it worked. And that’s never done—there never was a plant like it before. It’s not like a steel mill or car assembly line or something. It was unique. 

Kelly: So tell me a little bit more about how you felt about being part of the secret project, and what it was like as a young man to have been swept out of, you know, your line in the Army to come to this—or swept out of school, I guess—to be recruited for such a project?

Snyder: You know, youngsters my age, when their country gets blasted like we were in Pearl Harbor, we get angry. We want to fight. I was just in my freshman year at the university, but a lot of the guys finished that semester and took off. I started corresponding with them in the Air Force and Navy.

I was still here because my draft board said, “You can enlist but we recommend you don’t.” My father and my high school principal got on my back and said the same thing. I said, “Okay.” And I entered school in the class of ’45; I graduated in the class of ’44, and right into the Army.

By early ’45—it was wintertime, anyway—I was in Oak Ridge. I had a lot of Army training beforehand in the ROTC at university, and citizens’ military training while I was in high school because I liked playing football and I liked the idea of Army, that sort of thing. But anyway, I wound up at Oak Ridge, and I was Army in uniform only. I was an engineer.

When I came to Oak Ridge, there were about 200 guys in the Special Engineer Detachment. By the end of our efforts, there were about 1,200, 1,300 of us. But all of us were just assigned to some professional duty at one of the plants or with the Army itself at headquarters, things like that. 

I felt like I was doing what the country wanted me to be doing. And I was in uniform and I was proud of that. When the first bomb fell, I was elated. So was all of Oak Ridge. We really celebrated.

I was very disheartened subsequently that some would condemn us. We ended the war. We killed a lot of people. They were Japs. They started it in Pearl Harbor. We finished it on their homeland. And I don’t want to make it sound like that’s revenge, but I think it’s balance. There were a lot of lives lost there in Japan, but it saved a lot more lives from the battle that would have occurred for us to invade Japan.

Besides, in the meantime, most people don’t realize it, our Air Force was just tearing up that country. There wasn’t much left when we dropped the atom bomb. But it brought them to their senses, to sit down and sign a treaty, or this may have gone on Lord knows how much longer. Something like Iraq; it doesn’t end unless you do something really desperate.

To answer your question, I had in mind, using the advantage of the GI Bill of Rights, to finish my Army service here and go back to school and become a dentist. When I entered school, I was going to be an aeronautical engineer and fly airplanes. I never got a pilot’s license because the Army, or the war, interrupted that.

And just like becoming a dentist, no, the manager for Union Carbide at K-25 said, “Herm, we’d like you to stay here.” 

“Oh, doing what?” 

“Just what you’re doing now. And I think if you will agree to that we can probably get you an early discharge.” 

Well, I talked this over with my wife, and she’d be pleased to stay here. By that time, we’d made a lot of friends and we were enjoying this part of the country. So I took the job with Union Carbide. From a personal standpoint, it was a professional opportunity.

And, having been in from the ground floor, an advantage to me, I grew with the plant. When I left there I was the production manager for the whole shebang: the powerhouse, the utilities system, and the cascade. I transferred to Y-12, to the technical division over there, so my whole career was with Union Carbide and in Oak Ridge.

Now, with Carbide and with this project, I did a lot of traveling, went other places and stuff like that. But this was home; this was where we raised our children. So, personal standpoint, I’m satisfied with my life. I reached the eighty-year stage and I’m still here.

I get my blood boiling sometimes when I hear other reactions about nuclear industry and nuclear armament. If it hadn’t been for continuing to build some bombs, we’d have been in another war pretty quick, I think. We call it the “Cold War,” and that’s what it was, a war.

So I think I made my contribution. I’m satisfied for what I did with my life, although I had to change tracks several times.

Kelly: That’s great. That was wonderful. Thank you! Is there any sort of funny stories or surprises or ironies—are there things people don’t usually ask, or might not even think about?

Snyder: Well, one funny story was that when I came here I was single, but I was engaged to a young lady up there in Pennsylvania, where I came from. And after being here a few months, it was obvious to me I’m going to be here for the duration. So I couldn’t tell her what I was doing or why I had that conclusion, but I said, “I think I’ll be here awhile. Why don’t we get married? You can come down here and be with me.”

Well, didn’t have much resistance there. Goodness, she reserved the chapel at the university, got the license, let me know when this would take place. I could ride the trains for free, so I rode the train up there. We got married. I had to buy a ticket to bring her along back, but I rode for free.

We got here, got off the train in Knoxville, and got on a bus to come to Oak Ridge. It dawned on me, I hadn’t done a darn thing about getting a pass to even get her into the city of Oak Ridge. Now, I had thought about making arrangements for us to at least have a room to live in when we got there. But here I had to leave this little Pennsylvania lady standing at Elsa Gate with those armed soldiers. Never been in Tennessee before in her life, standing there with our luggage while I hitchhiked into town to get a pass, then hitchhiked back to Elsa gate. And now it’s funny but, oh, our marriage had a good test ride right off the bat. [Laughter.]

Then the place I had to live—like I say, the Army didn’t have anything for us but hutments, and they were terrible. I mean, you could see through the floor and everything. I didn’t want to put her in one of those. So I did some advertising, got in touch with an old couple that had a one-room apartment. It was called an “H apartment” in those days, and a one-bedroom apartment. They said that they’d let us have the bedroom. We’d share the kitchen and a bath and they’d sleep in the living room.

Well, I went up and looked it over and we talked. The only thing I had to do was pay the rent. Well that was all right, it was a place to stay. But we weren’t there more than a week and we were sure we had to find something different. And I told my wife then, “Well, if you get a job, you’ll be eligible for housing.” Hah! And the next day she got on the bus with me going out to K-25 and got herself a job. And fortunately they had one they could put her on that didn’t immediately require her clearance. It was outside the area. She went to work right away. Then housing got better. 

Everybody in Oak Ridge, practically, used the buses. You may have heard this already but I think they had over 400 buses operating all the time, bringing people in from outside Oak Ridge to work, providing the transportation in the town. And we could just get on the bus and go anywhere we wanted to. There was a main bus terminal, side bus terminals.

There weren’t many cars. Of course, there wasn’t much gas and cars weren’t being made anymore. So we got around a lot on buses in Oak Ridge, and visiting areas of Tennessee and getting familiar with this part of the country. So when I got out of the Army, that’s why we had no trouble making up our mind to stay right here.

I had another funny story came to mind and now I forgot it already. But the community was extraordinary. Young folks, lots of kids. We had a home in the Pine Valley area. We had an elementary school there that was in walking distance, a neighborhood shopping area within walking distance, a grocery, a drug store, a barber shop, dress shop or something else. All these lakes around us. We enjoyed the water.

I didn’t become a golfer ‘til I retired. I didn’t have time while I was working—that’s a time-consuming activity. Now I enjoy golf, but Oak Ridge had a lot of athletic activities. There wasn’t television at that time, so everybody was either interested in watching what was going on or participating in it. All kinds of athletic leagues. It was a good life.

Now a lot of our friends have passed on. Some of them left right after the war. But the community went from 75,000 down to about 27,000 or 28,000. But the friends we had here, most of them stayed, as I did. And we really had an Oak Ridge community.  

Since then, of course, things have changed. New activities, younger people coming in all the time, so that now it’s probably more a retirement home than a young kids’ home in Oak Ridge. Seriously, a lot of old folks. In retirement, there aren’t too many that wanted to go. These families that had six or seven in one house still have the house with two of them. That’s why, even though our population’s down, the housing keeps growing. There’s fewer people in each house.

I also got involved in civic affairs then. I was president of the Chamber of Commerce for a while, on boards for the city: a human resource board, planning commission. Became a real local, as did a lot of the other guys. You mentioned [Bob] Dyer and [Joe] Dykstra, those fellows. We were all buddies in the early years, putting in all those hours and catching sleep when we could.

Kelly: That’s great. I know you didn’t get down to the K-25 event yesterday, but we’ve been working with Bill Wilcox and others to try to—

Snyder: There’s a man—I hope he survives it. He has become our historian, very active in it. Enthusiastic, spends a lot of time on it. And he’s no youngster either—he’s about my age, I guess. And, by the way, he comes from my hometown. We come from the same place.

Kelly: Allentown?

Snyder: Yes. He went to Virginia to go to college. I stayed up there and went to Lehigh [University] in Bethlehem, Pennsylvania, right across the river from Allentown.

Kelly: I’m just going to ask if you could comment on whether we ought to be preserving some of these properties for future generations, or the history of what happened here in Oak Ridge during the Manhattan Project?

Snyder: Yes, I think so. 

Kelly: Okay. Can you say that? Because they won’t hear my question. Can you make that a statement? Because when we edit the film no one’s going to hear any of the questions that I ask, so instead of just agreeing with me, just make a sentence so people understand the context.

Snyder: Okay. Well, I think what was done here was a credit to the country, to the Army, and to the people. During this wartime period, everybody had one objective and that was to win this war, and as soon as we could. The armed services had grown to tremendous capacity for warfare. We were fighting wars on both sides of the earth. The female population of the country had become a factor in industry.

And an incident like this develops into just a magnificent example, where, with good direction and organization, this Manhattan District evolved and was productive, and encouraged people and recruited people to perform the tasks at all levels, the highly scholastic and scientific grade on down to the craftsmen and the ladies participating. They were important to Oak Ridge jobs within the city and within the plants.

It’s history that I think ought to be preserved, just like we do battlefields. There’s a limit to how much land one can devote to this sort of thing, and how much expense, and it’s not to have another park—parks are nice, but just so there’s something people can see. You know, we go around to see where important people are buried and all you see is a grave. But it’s a matter of respect for what people did. I hope our subsequent generations will respect what we did here. There are plenty of pictures.


Copyright:
Copyright 2014 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.