Interview with Delbert Sylvester Barth, March 18 2005

Nevada Test Site Oral History Project University of Nevada, Las Vegas Interview with Delbert Barth March 18, 2005 Henderson, Nevada Interview Conducted By Mary Palevsky © 2007 by UNLV Libraries Oral history is a method of collecting historical information through recorded interviews conducted by an interviewer/ researcher with an interviewee/ narrator who possesses firsthand knowledge of historically significant events. The goal is to create an archive which adds relevant material to the existing historical record. Oral history recordings and transcripts are primary source material and do not represent the final, verified, or complete narrative of the events under discussion. Rather, oral history is a spoken remembrance or dialogue, reflecting the interviewee’s memories, points of view and personal opinions about events in response to the interviewer’s specific questions. Oral history interviews document each interviewee’s personal engagement with the history in question. They are unique records, reflecting the particular meaning the interviewee draws from her/ his individual life experience. Produced by: The Nevada Test Site Oral History Project Departments of History and Sociology University of Nevada, Las Vegas, 89154- 5020 Director and Editor Mary Palevsky Principal Investigators Robert Futrell, Dept. of Sociology Andrew Kirk, Dept. of History The material in the Nevada Test Site Oral History Project archive is based upon work supported by the U. S. Dept. of Energy under award number DEFG52- 03NV99203 and the U. S. Dept. of Education under award number P116Z040093. Any opinions, findings, and conclusions or recommendations expressed in these recordings and transcripts are those of project participants— oral history interviewees and/ or oral history interviewers— and do not necessarily reflect the views of the U. S. Department of Energy or the U. S. Department of Education. UNLV Nevada Test Site Oral History Project 1 Interview with Delbert Barth March 18, 2005 Conducted by Mary Palevsky Table of Contents Introduction: USPHS biophysicist, transfers to Las Vegas, NV to create models and conduct measurements of Iodine 131 in animals on the NTS farm 1 Brief summary of work in U. S. Army Chemical Corps and transfer to the USPHS, work on measuring radioactivity from Pike and Pin Stripe 2 Genesis of the I131 measurement program at the NTS, explanation of how I131 enters the human body and its effects on human organs, concern expressed by Native Americans who may have consumed exposed animals, USPHS focus on children who may have consumed milk of exposed dairy cows 3 Political impetus for the I131 testing program, concerns of the AEC about radiation exposures and safety 6 Describes work on I131 measurements in Area 15, NTS, physical setup of farm and laboratory, composition of staff, nature of tests 7 Work on Palanquin ( Plowshare) and with Kiwi nuclear reactors 10 Major problems to be addressed: effects of low- level radiation exposure on people over time, complexities of exposure studies, different viewpoints on dangers of exposure to groups such as Downwinders 15 Participation in HEDR Project and HHES in Hanford, WA, working with Downwinders and incidences of thyroid disease 16 Comparison of retrospective dosimetry study ( HEDR Project) and case control study, and discussion of uncontrollable factors in epidemiological studies 17 Importance of low- level versus non- low- level radiation dangers, especially for Downwinders near the NTS; bystander and genetic effects 20 Establishment of Environmental Research Center, UNLV 22 Selected as Head of Bureau of Criteria and Standards for National Air Polution Control Administration ( NAPCA) 22 Becomes Director of EPA research group ( NC), then Director of Environmental Monitoring Support Laboratory ( later National Environmental Research Center), EPA, Las Vegas, NV 23 Promoted to Deputy Assistant Administrator for Health and Ecological Effects Research, EPA ( Washington, D. C.) 24 Describes EPA offsite monitoring program in Las Vegas, NV while Director of EPA laboratory 24 Transfers to UNLV, retires from the EPA, becomes advisor to Harry Reid Center for Environmental Studies, moves to Environmental Studies Department as professor, retires from UNLV 25 Talks about work with Harry Reid Center ( UNLV) on risk assessment and quality assurance for Yucca Mountain Project 26 Conclusion: Discusses importance of accuracy and quality assurance of data 31 UNLV Nevada Test Site Oral History Project 2 collected on Yucca Mountain Project Conclusion: Beginnings of EPA’s National Environmental Research Center at UNLV, and importance of relationship between EPA laboratories and universities 32 UNLV Nevada Test Site Oral History Project 1 Interview with Delbert Barth March 18, 2005 in Henderson, NV Conducted by Mary Palevsky [ 00: 00: 00] Begin Track 2, Disc 1. Mary Palevsky: Dr. Barth, thank you so much for talking to me again. I thought a good place to start again would be to recap the program you were hired to do at the NTS [ Nevada Test Site] in 1963; to address the question of the models used for offsite radiation exposure, I guess that would be the way you’d put it, at the test site; give a little background about how that came to be and where you were at the time. Delbert Barth: Actually, I had completed my Ph. D. at Ohio State University in biophysics and I was working in Washington, D. C. for the U. S. Public Health Service when I was asked if I would like to come to Las Vegas to develop a program for doing a better job of linking sources of radioactivity generated at the Nevada Test Site to levels of iodine 131 [ I131] which would be found in the offsite population. In the early days of testing, it simply was not appreciated how important the levels of iodine 131 could be. And so those levels were not measured in the beginning. So what we had to do was to try to reconstruct what those levels might have been by developing models. In order to develop those models, we had to do a certain amount of experimentation and also take advantage of any inadvertent releases from the Nevada Test Site. In early 1963 there was a planned event at the Nevada Test Site, and we had developed an experiment where we were going to be measuring air concentrations of radioactivity and forage concentrations and concentrations in the milk at various dairies, particularly over in Utah, since most of the radiation that left the Nevada Test Site moved in an easterly or northeasterly direction and exposed certain dairies in Utah. So we had this experiment all ready to go, and at the last minute our administration decided to sign a treaty which would not allow any nuclear UNLV Nevada Test Site Oral History Project 2 tests to be conducted in the atmosphere [ Limited Test Ban Treaty, 1963]. So this particular test was cancelled at the last minute. So we never did achieve the experiment that we had hoped to develop in early 1963. So ultimately what we had to do was to try to develop a somewhat artificial situation which was having our own forage, our own dairy cows, in a controlled location in Area 15 at the Nevada Test Site. We could expose our own forage and our own dairy cows to different levels, small levels, of radioiodine aerosols, and then to measure the buildup and decay of iodine 131 in the milk of our own dairy cows. And in addition to that, we always had a crew ready in case any of the events leaked from the test site. And there was one that did leak and exposed some of the dairy cows— well, and the first instance was the Pike event which exposed dairy cows in Las Vegas. There were a couple of dairies here in Las Vegas at that time. So we were able to get some measurements from that. And then we got a lot of measurements from an event called Pin Stripe which released radioactivity [ 00: 05: 00] over parts of Nevada and then on into Utah. But it was a relatively small amount and so we were able to get measurements in Nevada but there wasn’t enough radioiodine that was transported to Utah to enable us to get the kind of measurements we needed in the milk there. And so it was the combination of those inadvertent releases, the data that we got from that, plus the data that we got from our own farm that enabled us to construct a model. Because what we were trying to do was to have an improved model for actually estimating what the doses of people in Utah to their thyroids from iodine 131 was back in the fifties when they were conducting tests and the iodine 131 was not actually being measured. And so our whole mission in life was to develop improved models for estimating dosage of human thyroids to iodine 131. So that’s what we were trying to do with the program. UNLV Nevada Test Site Oral History Project 3 A couple of questions about that. Back historically, you’re in the Public Health Service, you have come over from the Army— you told me that story last time— and what was your rank in the Public Health Service at that point? When I transferred from the Army into the U. S Public Health Service, I was a major in the Army, Army Chemical Corps, and I had been trained especially in chemical, biological, and radiological warfare. And so I went from trying to estimate when we actually use weapons, how effective those weapons would be on the people that we were using them on in the Army Chemical Corps, over to the U. S. Public Health Service where the major concern was the safety of people from dosages of radiation which they received. So I transferred directly over. I was a major in the Army; I became a lieutenant commander in the U. S. Public Health Service. That’s an interesting point that you raise, and it was actually something I was thinking about before I came over this morning, is that shift from the warfare point of view to another aspect of the Cold War, which is we’re testing and the decision had been made that it was necessary to test, and then the safety issues that are raised by that. So in your own mind, was there any, for lack of a better word, psychological shift or—? Actually I really didn’t feel any psychological shift because although I had been trained to use nuclear weapons and to help to control and design the use of nuclear weapons in warfare, we never used them after I was trained in this program. So even though I had the knowledge, we never used it, and so it was very simple to just turn the knowledge around and worry more about safety than about adverse effect deliberately on an enemy. So it was really not a problem. Then explain to me the genesis of this particular work that the Public Health Service is asked to do out at the test site. We were saying before we started to film, I asked if it was an AEC [ Atomic Energy Commission] initiative. What was the sort of administrative genesis of this program? UNLV Nevada Test Site Oral History Project 4 Actually, the Atomic Energy Commission funded the entire program, and they did it out of their operational budget. It was not really from the research and development budget of the AEC. It was out of their operational budget because they wanted to be sure that they were not allowing too much dosage of iodine 131 to offsite populations, both in Nevada and Utah and in other locations as well. So it was the operational aspect that actually funded our project, and not the research and development program. [ 00: 10: 00] But you said also that it was not only looking forward but also a model that would look back to what had already occurred. Well, the whole reason for this program was to do our best to develop an improved model which would predict what the doses of radioiodine would be from a release from the test site, as well as what they were in the past when we know what the yield was but we had not measured the levels of radioiodine, and so we needed an improved model in order to estimate those levels. You said a few moments ago that there was really not the consciousness early on about the iodine. No. It simply was not appreciated that— what you really need to do in radiological health is determine what the critical organ is in the human body and then also what the critical radionuclide is that doses that critical organ. And it was not appreciated back in the early fifties that iodine 131 and the thyroid were the two— iodine 131 was the critical radionuclide and the thyroid was the critical organ in human beings. That was not appreciated, so they were not measuring those doses back in the fifties. Now in layperson’s terms, help me understand that a little better. That means that if there’s too much of the iodine 131, it deposits in the thyroid, is it—? UNLV Nevada Test Site Oral History Project 5 Well, first it has to get inside the body, and it gets inside the body by many different ways. If it’s in the air, you can inhale it, and once it gets inside the body, it will get into the bloodstream and then it actually goes to the thyroid gland and a certain fraction of all that goes into the body is actually deposited in the thyroid gland. So you can get it via the air you breathe, the water that you drink, the food that you eat. And the major food of concern is milk because that is the critical exposure route that you have to worry about because that gives you the maximum dosage to the thyroid gland in the general situation. Of course, if somebody doesn’t drink milk, then that’s not going to be a problem for them. But almost always, the major person of concern is a young child drinking milk from a dairy cow which has not gone through all of the processing. Because the iodine 131 has a half- life of eight days, which means eight days after you have a certain level of iodine 131, you will only have half that much. So the longer delay time from the time the iodine 131 is produced in the middle of a nuclear bomb to the time it gets into the milk and then the milk is consumed, the lower the dose is going to be. What about other animals that are eaten? I’ve been talking to some American Indian people, and there’s been some science done on whether, for instance, a rabbit that’s eaten in the early fifties by the northern Nevada tribes, is that also something that would be an iodine pathway or however you want to say it? Yes, it definitely would be. If you are consuming animals that have been exposed and that have radioiodine in their blood, most people would probably not eat the thyroid gland of the rabbit, but there is always a certain fraction of the total that gets into the rabbit via the grass it eats or the air that it breathes that will be left in the muscle, essentially, which is what most people eat of the rabbits. Usually you would not eat the thyroid gland. But there would be some, not only rabbits but we were concerned also about deer, and we had a program where we sampled deer UNLV Nevada Test Site Oral History Project 6 [ 00: 15: 00] periodically at the test site and measured the amount of iodine in the thyroid gland of the deer. But this was of course very late and long past the time when the maximum amount of radioiodine was being released from the test site. So what we had to do, again, was to try to develop models for what might have been the case back in the early, early days. And our concern, our major concern always was with small children drinking milk from a dairy cow on a ranch where you would not have the decay period of having it collected from the ranch and go to a place where it is processed and then bottled and then taken to grocery stores and sold. Can you tell me a little bit about the— was there a political impetus for this program? I’m asking you because now there’s a lot of publicity and has been a lot of activism on the part of downwind populations about exposures, but back in the early sixties, was AEC being pushed to do this or did this come from their own internally, do you know? Well, I think it was a combination. I really don’t know the answer to your question, but I can speculate and I would speculate that it was a combination. The public health agencies felt that this was necessary and the Atomic Energy Commission wanted to conduct their tests in a way that they could ensure safety. So they wanted the information as well. So it was a mutual situation where both the U. S. public health agencies and the people who were doing the testing wanted to have better models so they could predict what kind of offsite exposures would occur as a result of leakage. Because by this time we had a total [ atmospheric] test ban treaty [ Limited Test Ban Treaty] and everything had to be conducted underground, so they were concerned mostly about leakage and whether or not any actions needed to be taken if leakage occurred in order to protect health and safety. So you use, I am assuming, some kind of mathematical model that you have to develop to extrapolate back in time from current time to what exposures might have been? UNLV Nevada Test Site Oral History Project 7 Well, after we had conducted this program for approximately five years, we came up with our best estimate model which started with the source term. And the source term is a reference for how much radioactivity was injected into the air at what location. Then in the modeling exercise you have to look at the various air currents, which way they blew the material, how high the material went, and how it got spread over various locations. And then as a result of all of that, how much was deposited on the forage which was being consumed by dairy cows and then get into milk and then be consumed by children. So the model had to start with the source term, how much of a yield was it and what kind of a nuclear bomb was it. Because they had reasonably good data for nuclear bombs. What percentage of the radioactivity would be radioiodine? So I had it a little backwards. So let me see if I’ve got this right and you can clarify again. You’re doing all these experiments at your location in Area 15, which I want to talk to you a little bit more about in a second, and from that you get certain data that then you go back and apply to this source term to figure out what exposures would’ve been based on this complex of factors. Well, the work that we were doing in Area 15, we used labeled aerosols. These were aerosols that were tailor- made to a certain particle size and labeled with iodine 131. So we were using iodine 131 itself, whereas when you try to develop a model that deals with real release from a [ 00: 20: 00] nuclear weapon, the iodine 131 is there with all of the other things. So you have to know what fraction of the total yield was radioiodine and of that fraction, how much was gaseous, how much was particulate, how that changed as a function of time and as it moved downwind, and what caused it to deposit on forage and how much of it went on forage at different locations. All of this was part of the kind of models that we were trying to develop. That’s extremely complex. UNLV Nevada Test Site Oral History Project 8 Very much so. So tell me a little bit about the physical setup in Area 15 and how these aerosols would be applied. Well, in Area 15 we had a water supply there and we just literally cleared the area off by moving all the rocks and we developed a plot of ground in which we planted alfalfa. And this is a common material that is consumed by dairy cows. And so we had our own growing alfalfa in Area 15. We had our own water supply; we had our own herd of dairy cattle; and we had all of the data information on each one of the cows with regard to how much milk they yielded and how that changed as a function of time when they became pregnant with calves and so forth. So we had all of that background information. And what we did was to release aerosols labeled with iodine 131, and had to have very carefully controlled conditions so we would be sure that we weren’t going to be harming anybody away from the Area 15 site. And the weather had to be just right, and what we usually sought was a very low- level wind which would move the materials very slowly across our forage grass, which was alfalfa, and then we would cut the alfalfa, and it’s called [ sp], what you get from that, and we would then feed it to our cows inside our dairy barn there. And we would measure the amount of material which was deposited on the forage. And we were able to tailor- make our aerosols so they went all the way from fairly large particles down to gaseous materials. And so we were able to see how things change as you change the character of the aerosol containing iodine 131. And that was all part of the modeling that we did. And our final report at the end of all of that summarized everything that we had done in the entire study. Now this report, was it published or was it submitted or—? UNLV Nevada Test Site Oral History Project 9 It was submitted to the Atomic Energy Commission and was subsequently published as an EPA [ Environmental Protection Agency] document. And that was about probably ’ 69 or ’ 70, in that time frame. So is that something that I can see in some sort of version, non- classified version? Oh yes, I have a copy of the report. Oh great. Two questions from what you just said. You must have had a very specialized kind of staff working for you, then, to be able to do these various things. Well, we did. I mean we needed veterinarians for help with the cows. We had a couple or three veterinarians on the staff. We needed physicists, aerosol physicists who understood how particles travel with air and how they deposit. And we needed farming people who understood how the grass grew, how fast it grew, because that affected the concentration. So yes, and we needed [ 00: 25: 00] chemists and people who could analyze various kinds of samples for how much radioactivity it contained. So we needed a large group of special people. And when we wound up, I think there were eighty- some people in the program when we finally finished the project. Did you recruit those people from Public Health, from existing—? When I first came on board, I was the only one and there were a couple of people who were already associated with the Las Vegas laboratory that were assigned to me. So we started off with like three, and then we analyzed the type of skills we needed and then went out and looked for them and interviewed people and hired them. Who were the people that you started out with? The one that I remember very closely was Joel Veater, V- E- A- T- E- R, and I’m not even sure where he is anymore, but he left Las Vegas a long, long time ago. And he was with Public Health? UNLV Nevada Test Site Oral History Project 10 Yes, he was with the Las Vegas laboratory, which was conducting the measurements offsite in order to document how much radioactivity left the test site. They had a group of sampling equipment set up in various locations around the Nevada Test Site, and when an event occurred they would go out and be measuring with various instruments, but in the early days those instruments did not measure iodine 131. They measured gross beta and gross beta plus gamma and gross gamma exposure, which you get from a very large [ 00: 27: 14] collection of radionuclides. And so you really couldn’t estimate exactly how much of that was iodine 131 because it would fractionate with time as it moved downwind, because some of it became more particulate, the gases attached themselves to particles and they changed, the character of this aerosol changed as a function of time. Then did you see any— I’m asking this a little bit because people think about this and people joke about it. When you’re having your cow herd – joke about it in sort of black humor, let me say – did you notice any birth defects or anything in the animals themselves? No, we did not. And one of the events, one of the Plowshare events – the name of this particular event was Palanquin – we had our cows staked out. And one of our sites where we had cows and hay out – this was done in the wintertime so we didn’t have any growing grass – we put hay out. One of our stations was on a hot spot on the hot line, as a result of which it was so highly radioactive that we couldn’t go back in immediately to get the kind of data we wanted. And our cows were in there all the time, so they were exposed to a large amount of radioactivity, and actually some of them developed gray hair as a result of the exposure to radiation. But we did not see any other adverse effects in the cows, other than seeing the hair on their head turn from black to gray. I know that Palanquin was a Plowshare, but was it— at this point it had to be underground, no? UNLV Nevada Test Site Oral History Project 11 Well, the whole Plowshare program was to determine how to build a sea- level Panama Canal, and so what they were trying to do was determine how big a hole in the ground you could [ 00: 30: 00] develop with an explosion, a nuclear explosion, and how much radioactivity was going to be left in that hole in the ground. So always the Plowshare events would release material. And also they were doing nuclear tests out at the nuclear rocket development program [ Nuclear Rocket and Development Station, NRDS] and we got measurements from some of those tests. From the reactors out there. From the reactors, yes. But that was a different kind of thing from the nuclear explosions. I mean it was still radioactivity caused by the chain reaction that you have for both reactors and for the nuclear explosions, but the character of the source term was different for those two cases. Reactor releases and nuclear explosion releases. So you would put animals out near the reactors or—? Actually, as I recall, we had animals out only on Palanquin. For the nuclear reactors, we just had measurement stations where we sampled the air, and we took various kinds of samples and then from that estimated how much if there would’ve been forage grass at this given location. I remember one thing that the nuclear reactor people had estimated that particles, high- level radioactive particles were coming out as they were running these reactors. They said all of these would be deposited probably within one to three miles of the location. So when one of the tests was conducted, we sent a team out, and from the weather we knew which direction it had gone, and we were seeking out these particles, and we found the last particle out eighty- four miles. And it was so dark, we couldn’t go any farther, so we terminated our study right there, but it became very obvious that these particles were not deposited very close to the reactor. They were UNLV Nevada Test Site Oral History Project 12 a special kind of particles and some of them had almost aerodynamic shapes, and so they kind of floated along with the air and went way out. So we had a lot of those particles that we brought back, and then we did extensive testing to determine the character of the particles that were coming out of the reactors. And what kind of instruments are you using to detect them that far out? Well, actually all you need to do to detect a highly radioactive particle is the simplest kind of a Geiger counter. That’s all you really need because they were highly radioactive, these particles, and if you got close to it, you could see it, and then you would keep circling till you got the maximum measurement, and then you would scoop up some of the soil and you would have the particle in there. And how much longer after the reactor run or whatever it was would you go out? I mean how much time would—? Actually, the very day that the reactor ran was when we were trying to get the measurements because remember, we were concerned mostly about iodine 131 and it has an eight- day half- life, so you want to sample when you’re going to get the maximum level. So you literally are following the particle across the desert. Yes, we were able to do that on one of the reactor tests. Do you remember what the reaction was when you told them it went farther than three miles? [ Chuckling] Well, they couldn’t very well negate our study because we brought particles back that we found way out there. So they were astounded, that’s my opinion, in seeing that the particles went out that far. I’m trying to remember. I believe it was the Kiwi reactor. That was the name of the particular reactor that they had this test and we were available for the test and [ 00: 35: 00] were out taking measurements and had heard about these hot particles because at a UNLV Nevada Test Site Oral History Project 13 previous test, one of our people at the farm wound up with a hot particle on his coat or on his clothing, and this was picked up when he went through a hand- and- foot counter. So we knew that the particles were getting away. It was a question of how far they were going. That’s very interesting. Kiwi was that reactor. It’d be interesting to later— I’m curious about what that was. Well, it’s very, very difficult to do an adequate risk assessment of what the hazards might be from these particular particles because there weren’t enough of them that you have a huge amount of particles in any given place, so in a large area you may have only one particle, and it would all depend on whether somebody was right there and inhaled that or ate it in some way in order to do the hazard assessment. But then you have to calculate the probability that that would take place if you’re going to do a meaningful risk assessment. And we were doing that only to get a comparison of the particles that were getting out there versus the kind of experiments we were doing, because we were mostly concerned with nuclear explosions, not with reactors, because the reactors were only in an experimental phase. They had never been installed on any kind of rockets or whatever. So you mentioned your own aerosols. You must have followed your own particles in the same way to make sure that they stayed within your predictable area? Yes, we were able to have downwind from our plot that we were releasing— we were releasing them over our growing crops, and so we had stations past the crops to determine what was going there. We were using trace levels because you can measure very small amounts of radioiodine and it wasn’t necessary to use a large level of dose which would cause a major problem offsite. We were careful to design the study in such a way that that couldn’t happen. So after the five- year period, your mission is basically completed there? UNLV Nevada Test Site Oral History Project 14 Well, that completed the studies that we were doing on radioiodine and our final result was an improved model for tracking radioiodine from its source to milk. And there were well- developed models to determine dose to thyroid once you had the amount that was in the milk and how much milk was being consumed. So those models had been well- developed. But what we needed to do was get a better handle on tracking the radioiodine from the source into the milk, and that was the real purpose of our entire study. We didn’t actually take it beyond that because you know it’s just not appropriate to use people in this kind of a study, so we never considered the final step of this. We took the information that was already available in the literature for the final step. Now in what way was this used, if any way? You report this back to the AEC. Well, actually the model that they were using at that time was the Pike model which we had developed when we got measurements at a farm called Habbart’s dairy farm, which doesn’t exist [ 00: 40: 00] anymore. It’s H- A- B- B- A- R- T, as I recall, but it doesn’t exist anymore. And they were using that Pike model and they felt that the model that we had developed was close enough to the Pike model that they didn’t have to switch over from the Pike to our model. But actually what we were able to do is essentially confirm that the Pike model was a reasonable one. So you concurred with that? Yes. And this dairy farm was up in Utah, the Habbart farm? No, no, no, it was right here in Las Vegas. It was in Las Vegas. OK. The Pike event leaked and came straight down the highway to Las Vegas. That’s right. That’s what you said. UNLV Nevada Test Site Oral History Project 15 From then on, they never would have a test if the winds were blowing towards Las Vegas. They learned from that. You never can be sure that it’s going to be contained, even though