This report describes the circumstances leading to the accident, attempts to reconstruct the nuclear reactivity conditions, and reviews the dosimetric means and results which were used to help determine the exposure of affected employees.

From abstract: "This report describes a functional mercury vapor detector which is a portable, self-contained, survey instrument, and had a minimum range from zero to two-tenths milligram of mercury per cubic meter of air."

A survey and analysis of the potential opportunity for the use of nuclear reactors to satisfy process and space heat requirements in the continental United States and Alaska has been completed. The greatest emphasis has been devoted to manufacturing industries that utilize large quantities of process heat.

From abstract: The planes and modes of fracture as a result of the mixture of beryllium and other elements were investigated.

Originally issued as S and P 1963A, Parts I and II. This report covers a design and feasibility study of a pebble bed reactor-steam power plant of 125 megawatt electrical output. The reactor design which evolved from this study is a two-region thermal breeder, operating on the uranium-thorium cycle, in which all core structural materials are graphite. Fuel is in the form of unclad spherical elements of graphite, containing fissile and fertile material. The primary loop consists of the reactor plus three steam generators and blowers in parallel. Plant design and system analysis including cost analysis and capital cost summary are given.

Abstract: A low-level airborne radioactivity survey of parts of Beaverhead and Madison Counties in southwestern Montana was undertaken from June 6 to October 14, 1955. Flying centered around the Ruby Range-Sweetwater Basin area and concentrated on the Precambrian metamorphic complex and Tertiary lake-bed sediments. No commercial uranium deposits were discovered, and no extensions were found of the few known small occurrences. Five areas of high background detected through the survey were investigated on the ground.

Introduction: These minutes report the fifth of a series of instrumentation conferences held on a classified basis with the atomic energy projects of Canada, the United Kingdom, and the United States participating.

Foreward: The primary purpose of this report is to present as an accumulation of basic information on the hot cells constructed to date by the United States Atomic Energy Commission.

Summary and conclusion: More than 4000 feet of Lower Miocene lake sediments were deposited upon a gneissic basement rock, at least locally. The sediments have been gently folded into broad anticlines and synclines and have been cut by high-angle faults with displacements on the order of 100 feet. Both basaltic (?) and acid andesitic lavas have intruded the sediments. A Pleistocene (?) conglomerate unconformably overlies all older exposed rocks. The lake sediments were considered to overlie the adjacent thick series of andesite flows (l). This was not established by a cursory examination. The sediments appeared to be in fault contact with the lavas although the relationship was always obscured by the younger conglomerate or alluvial cover. Since a dike of this acid andesitic composition was observed cutting the sediments, there is a possibility that the lake sediments are older than or contemporaneous with the thick extrusive andesite series.

From abstract: A team consisting of R. A. Lindblom, S. A. Mayer, R. G. Young, W. L. Chenoweth, R. F. Droullard, and I. T. Fisk made a reexamination of the Anderson mine (Uranium Aire) of Interstate Oil and Development located near Wickenberg in Yavapai County, Arizona. The field examination was made from August 22, 1958 to September 2, 1958. This team was formed to resolve differences between company and AEC ore reserve estimates. A cooperative effort in which the company supplied labor, limited additional drilling and both parties were in attendance during the sampling resulted in the collection of additional data. Special attention was given to assessing the in-hole assaying with radiometric equipment by IOD and AEC, evaluation of tonnage factors, moisture content, continuity of ore, and current mapping of stripped and mined areas.

Abstract: In 1958 geologists of the U.S. Atomic Energy Commission and the Instituto de Investigaciones Geológicas de Chile made a reconnaissance for uranium in the Mamiña area, Province of Tarapacá in northern Chile.

Abstract: The Elqui-Vicuna area, Coquimbo province, Chile, was selected for uranium reconnaissance on the basis of two known uranium occurrences and favorable area-wide geologic indications of the possible presence of uranium in commercial quantities.

Preface: The Fuel Elements Conference held in Paris, France, November 18 to 23, 1957, under the joint sponsorship of the U.S. Atomic Energy Commission and the French Commissarat à l'Energie Atomique (CEA), provided an intensive review of fuel-element fabrication practices and behavior of fuel elements under in-pile irradiation and when subjected to corrosive media.

Proceedings of the 1958 Nuclear Merchant Ship Symposium.

Introduction: This exploratory work was undertaken as a preliminary evaluation of the area's uranium potential, and was limited to reconnaissance for favorable geologic indications of uranium, which included visits to selected localities and mining districts.

Although uranium gas first discovered in the Carrizo Mountains area in 1918, the ores were not developed until 1942. They have, however, been mined continuously since that time. Formations in the area range from the Pernian Cutler through the Cretaceous Mancos shale, and all are intruded by a dioritic laccolith and its related dikes. The older structures, which include the Defiance Uplift, the San Juan Basin, and the Four Corners Platform are somewhat disrupted by the effects of the intrusion. A number of mines are described and mineralogical and geochemical studies made are outlined. The primary uranium mineral is unknown, but the chief uranium ore-mineral is the secondary mineral, tyuyamunite. It is concluded that there is at least minor structural control of the ore bodies along sedimentary trends and joints, and that all ore bodies of 500 tons or more are on the Defiance monocline or its extensions. The uranium may have been syngenetic in the sediments, and redistributed by solutions or, more likely, that it rose vertically in hydrothermal solutions from the local intrusive bodies.

From Purpose, Scope, and Methods: The objective of this study was an evaluation of resources of the Carrizo Mountains area. Four factors: distribution of ore bodies, relation of uranium to the host rock, relation of ore to structure, and circumstances that might precipitate uranium were studied in search of data bearing on manner of distribution of ore, the time and causes of deposition, and the probable source of the uranium-bearing solutions.

Abstract: In a study of the comparative importance of sedimentary and tectonic ore controls and in search of data bearing on the origin of the deposits, ten mines in the Lukachukai Mountains, Apache County, Arizona were examined in detail. All commercial deposits in the area are in the Salt Wash Member of the Morrison Formation of Jurassic age. The ore bodies are elongate and horizontally lenticular in shape and consist of one or more ore pockets surrounded or separated by protore. The composite length of ore bodies consisting of two or more ore pockets separated by subore grade material ranges up to 1,100 feet; individual ore pockets range up to 350 feet in length. Elongation is usually at least three times the width and is parallel to paleostream depositional trends measured in and near the ore bodies. Claystone and/or siltstone units nearly always underlie and frequently overlie the host sandstone units. Ore occurs most frequently in trough-type, cross-stratified sandstone which fills scours and channels in the underlying claystone units. Lithofacies maps and mine mapping show that ore bodies are restricted to areas of rapid lateral color change which in general are also areas of rapid change in the ratio of …

Abstract: A calculational method is presented which may be used to determine fast and thermal neutron flux distributions at deep neutron penetrations in hydrogenous shields.

Abstract: This report outlines the general techniques developed for replacement of PRE in-cell equipment or equipment components.

Abstract: This report presents a description of the Organic Moderated Reactor Experiment (OMRE), of the hazards associated with this experiment, and all of the safeguards taken to ensure the safety of the operating personnel and the population of the surrounding area.

Abstract: The concept of a tapered fluidized bed is explored briefly. Data are given showing that in bench scale apparatus a tapered bed gives better fluidization with some materials that are difficult to fluidize in a conventional cylindrical bed.

The design of a waste-gas treatment system for organic moderated reactors requires a knowledge of reactor waste-gas composition, generation rate, and radioactivity. To obtain data on these variables a continuous stream analyzer was constructed to analyze the waste gas from the Organic Moderated Reactor Experiment (OMRE).

Abstract: Two 20-foot-long, 7-foot-diameter, 10-gauge structural-plate pipes having longitudinal joints with 8 bolts per foot were buried and tested in the Smoky event of operation Plumbob at nominal predicted pressure levels of approximately 170 and 195 psi.