Summary Report, Test Group 57 Operation Plumbbob - Preliminary Report

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Available from the Office of Technical Services Department of Commerce Operation PLUMBBOB — Preliminary Report SUMMARY REPORT, TEST GROUP 57 Weapons Effects Department Nevada Test Site „ Albuquerque, New Mexico Commission, no y expressed or implied, or the use ition, apparatus, me resulting from the

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This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency Portions of this document may be illegible in electronic image products. Images are produced from the best available

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This report is published in the interest of providing information which may prove of value to the reader in his study of effects data derived principally from nuclear weapons This document is based on information available at the time of preparation which may have subsequently been expanded and re-evaluated. Also, in preparing this report for publication, some classified material may have been removed. Users are cautioned to avoid interpretations and conclusions based on unknown or incomplete data. AEC Technical Information Service Extension Oak Ridge. Tennessee

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On April 24, 1957, Operation Plumbbob Test Group 57 conducted a detonation of a device for the purpose of studying the plutonium hazards from accidents. The objectives were to estimate the immediate and long-term distribution of plutonium and gain an understanding of how this distribution comes about, to conduct a bio medical evaluation of plutonium-laden environments, to investigate relevant methods of decon tamination, and to evaluate alpha field survey instruments and monitoring procedures. In the order mentioned, these objectives define four programs designated as 71, 72, 73, and 74, The results of Program 74 show that field survey methods can be relied upon to delin eate the areas contaminated by an accident, and the results of Program 73 show that decon tamination can be carried out successfully. Through analyses of collecting pans. Program 71 determined the areas covered by significant levels of contamination. Strictly speaking, these particular contours are only valid for the particular wind structure which obtained at the time of the shot, but it is expected that a basic fallout model will be prepared from these data which will permit extrapolation to other wind conditions. Air samplers indicated high airborne concentrations of respirable plutonium remarkably far downwind. Nevertheless, the amounts of plutonium picked up by animals exposed by Program 72 do not seem excessive. A full evaluation of these animal data has yet to be0' carried through, since the biological processes being studied are very slow.

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Conception of Test Group (TG) 57 experimentation began January 18, 1957. Field readiness was achieved by April 10. Experience and technical competence made possible much that was done. Most impressive was the fact that enthusiasm and determination compensated where experience was lacking. Although broad plans were generated at or near Program Director levels, they were improved and refined by all who worked on them. Exemplary performance was so much the rule that all participants deserve praise in like In an operation so hastily contrived and so quickly executed, outside support becomes the success determinant. This was so extraordinarily true of the TG 57 effort that especial commendation is given to: Phil Allen, of the U. S. Weather Bureau, for his guidance through two disheartening weeks of weather delays. Bill Johnson and the REECO Health and Safety Division personnel who some three times placed or replaced the 4, 000 sticky pans over the 70-square-mile test field and recovered 3, 500 pans postshot. Claude Benedix, of the S-6 office, whose serious appraisal of field construction requests saved numerous oversights. Jesse Friesen, REECO Area 13 foreman, who somehow made all the unreasonably last-minute needs materialize along with the others. Charley Smith, REECO operating engineer, for his devotion to the Project and the careful logging of Area 13 activities to make record of many meaningful incidents that would otherwise now be forgotten. Gordon Dunning, ofDBM/AEC, for his continual encour agement and support.

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CHAPTER 1 MOTIVATIONAND MISSION...................................................................................................... 17 2. 3 The Fallout Experiment............ 27 2. 3. 1 Fallout Collector Array .......... 27 2.4. 2 Natural Resuspension Studies ......... 34 CHAPTER 3 PROGRAM 72 - BIOMEDICAL FIELD STUDY OF PLUTONIUM 3. 2 The Animal Experiment 39 3.2.1 Exposure to Cloud Passage. ......... 39

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CHAPTER 4 PROGRAM 73 - DECONTAMINATION AND MONITORING 4. 2 Decontamination of Paving and Building Materials ...... 49 4.2.1 Alpha Survey Instruments .......... 49 4. 3 Decontamination of Land Areas .......... 51 CHAPTER 5 PROGRAM 74 - SURFACE ALPHA MONITORING AND MONITOR 5.2 The Alpha Survey. ............. 61 5.2. 1 Choice of a Standard Surface ......... 61 7.1. 1 Data From Alpha Survey Instruments ....... 73 7.1.2 Survey Data Renormalized . 75 7. 2 Air Sampling During the Fallout Period.................................................................... . 82 7.3 Air Concentrations Versus Time.................................................................................................... 82 7. 3. 1 Extrapolations to Inhalation by Man ........ 83 7.4 Surface Monitoring as a Function of Time ........ 87 7. 5 Air Concentrations Downwind From a Resuspension............................................................. 87 7.6 Animal Uptake of Plutonium ............ 90 7. 6. 3 Animal Data Summary ........... 93

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7.7. 1 General Results for 2-x-2-Foot and 10-x-10-Foot Pads ... 94 7.7.2 Decontamination of 24-x-50-Foot Pads ....... 94 7.7.3 Decontamination or Fixation of Land Areas ...... 96 7. 7. 5 Decontamination of Equipment ......... 97 7. 8 Controversy of Ground Concentrations ......... 97 7. 9 Plutonium in Soil Versus Time ........... 98 8. 1 Plutonium on the Ground ............ 99 8. 2 Plutonium in the Air ............. 99 8. 3 Plutonium in the Dogs ............. 100 8. 4 Plutonium Removal and Fixation .......... 100 CHAPTER 1 MOTIVATION AND MISSION 1. 1 Organizational Structure of Test Group 57 ........ 21 CHAPTER 2 PROGRAM 71 - PARTICULATE PHYSICS 2. 1 Facilities Layout, Instrumentation Array, and General Topography 2.2 Fallout Collector Station.............................................................................................................. 27 2. 3 Surface-Level Fallout Collector Station................................................................................ 27 2. 6 Air Samplers, Pumps, and Motor.......................................................................................... 31 2. 7 Electrostatic Precipitator for Balloon Suspensions ...... 32 CHAPTER 3 PROGRAM 72 - BIOMEDICAL FIELD STUDY OF PLUTONIUM CHAPTER 4 PROGRAM 73 - DECONTAMINATION AND MONITORING 4. 2 Corrugated Roofing Samples, 2 Feet Square.................................................................................51 4. 3 Plot of Land Decontamination Areas ......... 52 4. 4 Plot of Air Sampler Array.........................................................................................................................54 4.5 Staplex Air Sampler With Adapter Head ......... 55 4. 6 Staplex Air Sampler With Annular Impactor.................................................................................56

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CHAPTER 5 PROGRAM 74 - SURFACE ALPHA MONITORING AND MONITOR 5. 1 Monitoring Probe With Standoff Clips ......... 62 6. 1 Adjusted Hodographs Prior to Operation on April 24, 1957, 6. 2 Adjusted Hodographs Prior to Operation on April 24, 1957, 6. 3 Adjusted Hodographs During Fallout, April 24, 1957, Station 25. 5 - 31 . . 68 6.4 Adjusted Hodographs During Fallout, April 24, 1957, Station 71-27 . . 69 6. 5 Mean First Hour Wind Pattern ........... 71 7. 1 Preliminary Isoconcentration Contours From Alpha Survey With Point Results in pgm/m^.............................................................................................................. 74 7. 2 Normalized Zones B and C Alpha Survey Contours ...... 76 7. 3 Normalized Zone B Alpha Survey Contours ........ 77 7. 4 Normalized Zone A Survey Data .......... 78 7. 5 Sticky-Pan and Acute Air-Sampler Assays, Plutonium Isoconcentration Lines and Acute-Dog Stations in Zone B................................................................................ 79 7. 6 Stocky-Pan and Acute Air-Sampler Assays, Plutonium Isoconcentration Lines and Chronic-Dog Stations in Zones B and C.................................................. 80 7. 7 Major Isoconcentration Lines and Mean Wind Hodograph ..... 81 7. 8 Air Concentration, Maximum Wind, Average Wind, and Rainfall as a Function of Time, Station 26. 9 - 35. 0 ................................................................................ 84 7. 9 Air Concentration Versus Time Postshot ........ 85 7. 10 Occupancy Required to Produce MPL (lung) in Man.................................................. 86 7.11 Activity Degradations Apparent to Alpha Survey Instruments .... 88 7. 12 Air Concentration Downwind From a Resuspension Activity .... 89 CHAPTER 3 PROGRAM 72 - BIOMEDICAL FIELD STUDY OF PLUTONIUM 3. 1 Arrangement of Animals for Acute Exposure ....... 40 3. 2 Arrangement of Animals for Chronic Exposure ....... 43 3. 3 Removal Schedule for Chronic-Exposure Animals ...... 44 7. 1 Time of Permissible Occupancy .......... 87 7.2 Tissue Assays for Animals Exposed to the Cloud. ...... 91 7. 3 Tissue Assays for Animals Placed Postshot ........ 92 7. 4 Tissue Assays for Late-Chronic Animals...................................................................... 93 7. 5 Summary of Median Values Reduced to Irradiations Per Unit Tissue Mass . 94

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7. 7 Effectiveness of Various Decontamination Methods 7. 9 Permanent Land Decontamination Efficiency 7. 10 Areas Within Ground Concentration Contours 7. 11 Earliest Program 71 Soil Sample Data .

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MOTIVATION AND MISSION Concern for the biomedical effects of plutonium predates the physical existence of plutonium* in any but miniscule quantities. A major factor in the choice of a site for the Hanford Works (1944), the original U.S. plutonium-production plant, was the possibility of plutonium contamination of the environs from a reactor accident. Appreciate, too, that the Hanford reactor was the first planned for more than a kilowatt rating. * From this worri some beginning, more breeder reactors were built and operated. Biomedical programs, intensive and numerous, grew with the industry to the extent that some claim that more is known of plutonium as a noxious agent than of any other substance. Radiological standards, in the form of maximum permissible levels (MPL) in body organs considered critical and maximum permissible concentrations in air and drinking water, are common knowledge throughout the atomic industry. Plutonium is an alpha emitter and therefore no real external hazard. Fortunately, the oxides of plutonium are essentially insoluble in the fluids of the GI tract (0.003 percent). Once in the stomach, their stay in the body is short, for they are excreted as an inert material with virtually no body assimilation. Inhalation is a different mechanism entirely and one which presents a considerable threat. Any particle small enough to reach the lower respiratory tract apparently has an excellent chance of clinging to alveolar surfaces and staying to do radiation damage locally, with a half life of approximately 1 year. Some of the finer particulate matter so captured may be taken directly into the blood stream over a period of several days. This material stays as a blood burden until its trace solubility allows eventual assimilation to the extent of some 70 percent of the material carried. This 70 percent is distributed principally in bone where it remains indefinitely as far as human life span is concerned. One cannot outlive the influence, because the alpha half life of plutonium-239 is of the order of 20,000 years. associated with the inhalation of plutonium are extended from research and industrial workers to an unschooled and unsuspecting public. * In historic times, that is.

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1.4 GENESIS OF PROJECT 57 A few weeks later, the manager of the Albuquerque Operations Office, with the sanction of DMA, requested Sandia to assume responsibility for arranging the experimental program, appointing a test director, and selecting a test site as soon as possible. About the first of January 1957, the Test Director and several members of the Sandia Corporation Weapons Effects Department, with the help of ALO Test Division, began a search for a test site which had an extremely low plutonium background and a reasonably flat area of about 50 square miles. In addition, it was thought preferable to find a site where mountainvalley drainage currents would induce a large amount of shear in either the early night or very early morning hours, likely shot times. It quickly became clear that no portion of the Nevada Test Site could be relinquished to this experiment because of the unknown length of time before the area could be returned to unrestricted or even mildly restricted use. Also, because of the size of the job and the time available, it was thought that remoteness from supply and support functions would make the task impossible. A close survey of areas contiguous with NTS focused attention rather quickly on two dry lake valleys: the Papoose Lake area and the large valley adjoining Groom Lake and northwest of it. Several of the planning group examined these two locations from the air, looking also for additional sites that might have been overlooked in the map study. This air survey immediately preceded the first general meeting of Project 57 on January 18, 1957, at which time outlines of experiments were drawn. The first general meeting was composed of members of the following organizations: AEP/UCLA, DBM/AEC, Sandia Corporation, and agencies from which support was expected, such as the U.S. Weather Bureau, the U.S. Public Health Service, and Reynolds Electric and Engineering Company (REECO). It was learned that the AEP/UCLA had made measurements in both Papoose Lake and Groom Lake areas and had discovered considerably greater plutonium background in the former site. Therefore, it was agreed that the Groom Lake valley should be the test site, if possible, and that the consent of the U.S. Air Force which controlled it should be sought immediately. Because the number of measurements of background in the two valleys did not give over whelming evidence of the superiority of the Groom Lake area, more extensive soil sampling throughout the area was required. A check of grazing rights prior to the meeting indicated that the livestock problem had presumably been eliminated, yet the aerial inspection showed

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60 to 80 cattle in the area. Finally, it was thought extremely important to start an immediate meteorological survey to determine the drainage pattern in the bowllike topography of the Groom Lake area and to find'how this drainage pattern faired into the higher wind structure. The remainder of the meeting was devoted to outlining specific experimental programs by separate committee action. Three committees met to consider Particulate Physics, Biomedical Experiments, and Plutonium Decontamination. The objectives each group set for itself and the scope of experimentation became the separate programs of Project 57 and are included in the following chapters, as is the program—added later—for field measurements with alpha instruments and for field monitor training. Because Project 57 would overlap preparations for Operation Plumbbob, it was renamed Test Group 57 and made a formal part of Plumbbob. Its organizational structure is shown in Four broad needs underlay the TG- 57 effort: 1. Means of estimating immediate distribution and long-term redistribution of plutonium from a nonnuclear detonation and an understanding of how they come about. 2. Biomedical evaluation of likely plutonium-laden environments. 3. Methods of decontamination of ground areas, pavements, building materials, etc. 4. Alpha survey instruments and field monitoring procedures to enable prompt estimation of contaminant deposition. Implicit here is an appreciation of the require ment for personnel trained in …