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At least 19 records

A Cultural Resources Inventory and Historical Evaluation of the Smoky Atmospheric Nuclear Test, Areas 8, 9, and 10, Nevada National Security Site, Nye County, Nevada

This report presents the results of a National Historic Preservation Act Section 106 cultural resources inventory and historical evaluation of the 1957 Smoky atmospheric test location on the Nevada National Security Site (NNSS). The Desert Research Institute (DRI) was tasked to conduct a cultural resources study of the Smoky test area as a result of a proposed undertaking by the Department of Energy Environmental Management. This undertaking involves investigating Corrective Action Unit (CAU) 550 for potential contaminants of concern as delineated in a Corrective Action Investigation Plan. CAU 550 is an area that spatially overlaps portions of the Smoky test location. Smoky, T-2c, was a 44 kt atmospheric nuclear test detonated at 5:30 am on August 31, 1957, on top of a 213.4 m (700 ft) 200 ton tower (T-2c) in Area 8 of the NNSS. Smoky was a weapons related test of the Plumbbob series (number 19) and part of the Department of Defense Exercise Desert Rock VII and VIII. The cultural resources effort involved the development of a historic context based on archival documents and engineering records, the inventory of the cultural resources in the Smoky test area and an associated military trench location in Areas 9 and 10, and an evaluation of the National Register eligibility of the cultural resources. The inventory of the Smoky test area resulted in the identification of structures, features, and artifacts related to the physical development of the test location and the post-test remains. The Smoky test area was designated historic district D104 and coincides with a historic archaeological site recorded as 26NY14794 and the military trenches designed for troop observation, site 26NY14795. Sites 26NY14794 and 26NY14795 are spatially discrete with the trenches located 4.3 km (2.7 mi) southeast of the Smoky ground zero. As a result, historic district D104 is discontiguous and in total it covers 151.4 hectares (374 acres). The Smoky test location, recorded as historic district D104 and historic sites 26NY14794 and 26NY14795, is the best preserved post-shot atmospheric nuclear tower test at the NNSS and possibly in the world. It is of local, national, and international importance due to nuclear testing’s pivotal role in the Cold War between the United States and the former Soviet Union. The district and sites are linked to the historic theme of atmospheric nuclear testing. D104 retains aspects of the engineering plan and design for the Smoky tower, instrument stations used to measure test effects, German and French personnel shelters, and military trenches. A total of 33 structures contribute to the significance of D104. Artifacts and features provide significant post-test information. Historic district D104 (discontiguous) and historic site 26NY14794 (the Smoky test area) are eligible for listing on the NRHP under Criteria A, B, C, and D. The historic site 26NY14795 (the Smoky military trenches) is eligible for listing under Criteria A, C, and D. Several items have been identified for removal by the CAU 550 investigation. However, none of them is associated with the Smoky atmospheric test, but with later activities in the area. The military trenches are not part of CAU 550 and no actions are planned there. A proposed closure of the Smoky test area with restrictions will limit access and contribute to the preservation of the cultural resources. It is recommended that the Smoky historic district and sites be included in the NNSS cultural resources monitoring program.

54 ENVIRONMENTAL SCIENCES↗

Weapon Physicist Declassifies Rescued Nuclear Test Films

The U.S. conducted 210 atmospheric nuclear tests between 1945 and 1962, with multiple cameras capturing each event at around 2,400 frames per second. But in the decades since, around 10,000 of these films sat idle, scattered across the country in high-security vaults. Not only were they gathering dust, the film material itself was slowly decomposing, bringing the data they contained to the brink of being lost forever. For the past five years, Lawrence Livermore National Laboratory (LLNL) weapon physicist Greg Spriggs and a crack team of film experts, archivists and software developers have been on a mission to hunt down, scan, reanalyze and declassify these decomposing films. The goals are to preserve the films’ content before it’s lost forever, and provide better data to the post-testing-era scientists who use computer codes to help certify that the aging U.S. nuclear deterrent remains safe, secure and effective.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

The distinct conditions of atmospheric and underground nuclear tests revealed by Zn isotopic compositions of nuclear debris samples

We analyzed the Zn isotopic compositions of nuclear debris samples from atmospheric and underground nuclear tests. Samples from the site of atmospheric tests exhibit a range of Zn isotopic fractionation (δ 66 Zn JMC-Lyon = 0.23–0.86 ‰) while samples from underground tests exhibit Zn isotopic compositions with minimal variation among samples and from terrestrial igneous rock standards (δ 66 ZnJMC-Lyon = 0.28–0.39 ‰). In conclusion, the larger range of δ 66 Zn JMC-Lyon observed in atmospheric test samples relative to underground test samples is likely the result of the open system characteristics of atmospheric nuclear tests and the closed system characteristics of underground nuclear tests.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗

Corrective Action Investigation Plan for Corrective Action Unit 105: Area 2 Yucca Flat Atmospheric Test Sites Nevada National Security Site, Nevada, Revision 0

Corrective Action Unit (CAU) 105 is located in Area 2 of the Nevada National Security Site, which is approximately 65 miles northwest of Las Vegas, Nevada. CAU 105 is a geographical grouping of sites where there has been a suspected release of contamination associated with atmospheric nuclear testing. This document describes the planned investigation of CAU 105, which comprises the following corrective action sites (CASs): • 02-23-04, Atmospheric Test Site - Whitney • 02-23-05, Atmospheric Test Site T-2A • 02-23-06, Atmospheric Test Site T-2B • 02-23-08, Atmospheric Test Site T-2 • 02-23-09, Atmospheric Test Site - Turk These sites are being investigated because existing information on the nature and extent of potential contamination is insufficient to evaluate and recommend corrective action alternatives (CAAs). Additional information will be obtained by conducting a corrective action investigation before evaluating CAAs and selecting the appropriate corrective action for each CAS. The results of the field investigation will support a defensible evaluation of viable CAAs that will be presented in the Corrective Action Decision Document. The sites will be investigated based on the data quality objectives (DQOs) developed on April 30, 2012, by representatives of the Nevada Division of Environmental Protection and the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office. The DQO process was used to identify and define the type, amount, and quality of data needed to develop and evaluate appropriate corrective actions for CAU 105. The site investigation process will also be conducted in accordance with the Soils Activity Quality Assurance Plan, which establishes requirements, technical planning, and general quality practices to be applied to this activity. The potential contamination sources associated with all CAU 105 CASs are from atmospheric nuclear testing activities. The presence and nature of contamination at CAU 105 will be evaluated based on information collected from a field investigation. Radiological contamination will be evaluated based on a comparison of the total effective dose at sample locations to the dose-based final action level. The total effective dose will be calculated as the total of separate estimates of internal and external dose. Results from the analysis of soil samples will be used to calculate internal radiological dose. Thermoluminescent dosimeters placed at the center of each sample location will be used to measure external radiological dose. Appendix A provides a detailed discussion of the DQO methodology and the DQOs specific to each CAS. This Corrective Action Investigation Plan has been developed in accordance with the Federal Facility Agreement and Consent Order that was agreed to by the State of Nevada; DOE, Environmental Management; U.S. Department of Defense; and DOE, Legacy Management. Under the Federal Facility Agreement and Consent Order, this Corrective Action Investigation Plan will be submitted to the Nevada Division of Environmental Protection for approval. Fieldwork will be conducted after the plan is approved.

54 ENVIRONMENTAL SCIENCES↗

Determing the Radiative Heat Transfer out of the Fireball of an Atmospheric Nuclear Detonation using Experimental Data

When Edgerton, Germeshausen and Grier, Inc. (EG&G) conducted the atmospheric nuclear tests in the 1950s, they made several continuous records of the light output over time with special "streak cameras." Once processed, these "streak films" contained long bands of varying optical density on black-and-white 35mm film. The purpose for creating them was to determine the time-dependent rate of radiative heat transfer out of the fireball. Back then, EG&G's manual examination methods were not precise enough to make complete analysis worthwhile, so the data was never fully analyzed. With the advent of new computer software, recently developed analysis techniques have reduced uncertainty in the data to where re-analysis is providing results far more reliable than anything EG&G published. Previously inaccessible information can now be accurately gathered from the original films. The method described here allows the streak films to be analyzed so a radiative power curve for an atmospheric nuclear detonation can be constructed using only experimental data. It was applied to five streak films here, though it may be applicable to other types of films as well. The data was plotted and compared to solutions generated with the Hybrid Chemistry (HYCHEM) software. The results are explained, and uncertainty values are provided. If the results from more films show consistency and the sources of uncertainty are mitigated, enough data may be discovered to create a correction factor for HYCHEM or to make more accurate yield determinations using G.I. Taylor's equations. Several other conclusions and recommendations are also posed.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

New Yield Estimates for Nuclear Detonations Over Water

One of the primary methods used by the United States to estimate the yields of atmospheric nuclear tests performed in the 1940’s, 50’s, and 60’s was to film each detonation with a high-speed camera, measure the blast radius as a function of time, and then use Taylor’s spherical blast wave equation to calculate the source energy (i.e., the yield). For surface detonations, the yield in Taylor’s equation was assumed to be twice as large as the actual yield to account for the energy reflected from the surface, assuming the ground was a perfect reflector. Recent simulations of surface detonations over water (referred to as barge shots) have shown that Taylor’s equation must be modified further to account for material entrainment and heat losses. We have computed this lost energy using a high-order radiation-hydrodynamics code to determine the reduction in blast radius vs. time. By analyzing simulation data in the same manner as film data, we have determined that a yield correction factor of 1.27± 0.04 should be applied to the barge shots.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

Corrective Action Investigation Plan for Corrective Action Unit 104: Area 7 Yucca Flat Atmospheric Test Sites, Nevada National Security Site, Nevada, Revision 0

CAU 104 comprises the 15 CASs listed below: (1) 07-23-03, Atmospheric Test Site T-7C; (2) 07-23-04, Atmospheric Test Site T7-1; (3) 07-23-05, Atmospheric Test Site; (4) 07-23-06, Atmospheric Test Site T7-5a; (5) 07-23-07, Atmospheric Test Site - Dog (T-S); (6) 07-23-08, Atmospheric Test Site - Baker (T-S); (7) 07-23-09, Atmospheric Test Site - Charlie (T-S); (8) 07-23-10, Atmospheric Test Site - Dixie; (9) 07-23-11, Atmospheric Test Site - Dixie; (10) 07-23-12, Atmospheric Test Site - Charlie (Bus); (11) 07-23-13, Atmospheric Test Site - Baker (Buster); (12) 07-23-14, Atmospheric Test Site - Ruth; (13) 07-23-15, Atmospheric Test Site T7-4; (14) 07-23-16, Atmospheric Test Site B7-b; (15) 07-23-17, Atmospheric Test Site - Climax These sites are being investigated because existing information on the nature and extent of potential contamination is insufficient to evaluate and recommend corrective action alternatives (CAAs). Additional information will be obtained by conducting a corrective action investigation before evaluating CAAs and selecting the appropriate corrective action for each CAS. The results of the field investigation will support a defensible evaluation of viable CAAs that will be presented in the Corrective Action Decision Document. The sites will be investigated based on the data quality objectives (DQOs) developed on April 28, 2011, by representatives of the Nevada Division of Environmental Protection and the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office. The DQO process was used to identify and define the type, amount, and quality of data needed to develop and evaluate appropriate corrective actions for CAU 104. The releases at CAU 104 consist of surface-deposited radionuclides from 30 atmospheric nuclear tests. The presence and nature of contamination at CAU 104 will be evaluated based on information collected from a field investigation. Radiological contamination will be evaluated based on a comparison of the total effective dose (TED) to the dose-based final action level (FAL). The presence of TED exceeding the FAL is considered a radiological contaminant of concern (COC). Anything identified as a COC will require corrective action. The TED will be calculated as the total of separate estimates of internal and external dose. Results from the analysis of soil samples will be used to calculate internal radiological dose. Thermoluminescent dosimeters will be used to measure external radiological dose. Based on process knowledge of the releases associated with the nuclear tests and radiological survey information about the location and shape of the resulting contamination plume, it was determined that the releases from the nuclear tests are co-located and will be investigated concurrently. A field investigation will be performed to define areas where TED exceeds the FAL and to determine whether other COCs are present at the site. The investigation will also collect information to determine the presence and nature of contamination associated with migration and excavation, as well as any potential releases discovered during the investigation. Appendix A provides a detailed discussion of the DQO methodology and the DQOs specific to each CAS.

54 ENVIRONMENTAL SCIENCES↗

Yield Estimates of three Historical Atmospheric Nuclear Explosions at Lop Nor, from Reduced Order Models of Regionally Recorded Rayleigh Waveforms and One Seismic Station: A Brief Communication

We use a reduced order model (ROM) for Rayleigh waveforms sourced by large atmospheric explosions along with data collected from a single seismic station (TLG) to estimate the yields of three atmospheric nuclear tests with order-megaton (MT) yields. These historical tests were conducted by China between 1973 and 1980 (CHIC 15, CHIC 16, and CHIC 26). We use our ROM to estimate yields of 2.34 MT (CHIC 15), 0.51 MT (CHIC 16), and 1.15 (CHIC 26) in the 20.5 s period band that are consistent with publicly accepted values of 3 MT (CHIC 15), 0.50 MT (CHIC 16), and 0.730 MT (CHIC 26).

58 GEOSCIENCES↗

Pertechnetate (TcO4-) reduction by reactive ferrous iron forms in naturally anoxic, redox transition zone sediments from the Hanford Site, USA

Technetium is an important environmental contaminant introduced by the processing and disposal of irradiated nuclear fuel and atmospheric nuclear tests. Under oxic conditions technetium is soluble and exists as pertechnatate anion (TcO4-), while under anoxic conditions Tc is usually insoluble and exists as precipitated Tc(IV). Here we investigated abiotic Tc(VII) reduction in mineralogically heterogeneous, Fe(II)-containing sediments. The sediments were collected from a 55 m borehole that sampled a semi-confined aquifer at the Hanford Site, USA that contained a dramatic redox transition zone. One oxic facies (18.0-18.3 m) and five anoxic facies (18.3-18.6 m, 30.8-31.1 m, 39.0-39.3 m, 47.2-47.5 m and 51.5-51.8 m) were selected for this study. Chemical extractions, X-ray diffraction, electron microscopy, and Mössbauer spectroscopy were applied to characterize the Fe(II) mineral suite that included: Fe(II)-phyllosilicates, pyrite, magnetite and siderite. The Fe(II) mineral phase distribution differed between the sediments. Sediment suspensions were adjusted to the same 0.5 M HCl extracted Fe(II) concentration (0.6 mM) for Tc(VII) reduction experiments. Aqueous Fe was low in all sediment suspensions (<2 μM) and below the Fe(II)aq detection limit (10 μM). Technetium(VII) reduction occurred in all anoxic sediments at depths greater than 18.3 m and reaction time differed significantly between the sediments (8-219 d). Mössbauer analysis of the Tc-reacted, 30.8-31.1 m sediment confirmed that Tc(VII) was reduced by solid-phase Fe(II), with siderite and Fe(II)-containing phyllosilicates implicated as redox reactive phases. Technetium-XAS analysis demonstrated that Tc associated with sediments was in the Tc(IV) valence state and immobilized as clusters of a TcO2·nH2O-like phase. The speciation of redox product Tc(IV) was not affected by reduction rate or Fe(II) mineralogy.

Environmental Molecular Sciences Laboratory↗

Light Output and Thermal Blast Analysis of Nuclear Fireballs

During the 1940s, 50s, and 60s, there were 210 atmospheric nuclear tests. Every test was extensively recorded with high quality motion picture films and photographs, providing a unique historic record, containing ~10,000 films, with a total of ~22 million frames of information. Much of what is known about the effects of nuclear weapons has been obtained from these tests. There are approximately 6500 scientific films that are in the process of being scanned by Lawrence Livermore National Laboratory and re-analyzed using modern computer techniques. The four major effects of a nuclear detonation are prompt radiation, shockwave, thermal blast, and fallout. The objective of this interim report is to describe recent efforts to extract benchmark data from the existing streak films using modern Figure-processing techniques. These new and, hopefully, greatly-improved data will provide our code developers with the benchmark data necessary to validate our modern computer codes that simulate nuclear weapon effects.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Yield Analysis of Nuclear Fireballs

During the1940s, 50s, and 60s, there were 210 atmospheric nuclear tests. Every test was extensively recorded with high quality motion picture films and photographs, providing a unique historic record, containing ~10,000 films, with a total of ~22 million frames of information. Much of what is known about the effects of nuclear weapons has been obtained from these tests.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

Theory and observations: Model simulations of the period 1955-1985

The main objective of the theoretical studies presented here is to apply models of stratospheric chemistry and transport in order to understand the processes that control stratospheric ozone and that are responsible for the observed variations. The model calculations are intended to simulate the observed behavior of atmospheric ozone over the past three decades (1955-1985), for which there exists a substantial record of both ground-based and, more recently, satellite measurements. Ozone concentrations in the atmosphere vary on different time scales and for several different causes. The models described here were designed to simulate the effect on ozone of changes in the concentration of such trace gases as CFC, CH4, N2O, and CO2. Changes from year to year in ultraviolet radiation associated with the solar cycle are also included in the models. A third source of variability explicitly considered is the sporadic introduction of large amounts of NO sub x into the stratosphere during atmospheric nuclear tests.

Isaksen, Ivar S. A.↗

Fallout Cloud Regimes

The U.S. Department of Defense (DOD), Department of Energy (DOE), and other organizations maintain operational nuclear explosion and atmospheric dispersion models to provide critical guidance on the expected effects of an accidental or deliberate explosion of a nuclear weapon (in this paper simply referred to as “device”). To be effective, these models must represent, as accurately as possible, the complex interactions of the blast, fire, and residual radiological hazards with the environment and population. One hundred atmospheric nuclear tests that form the basis for many models were conducted at the Nevada Test Site (NTS) (now referred to as the Nevada Nuclear Security Site, NNSS) in a dry desert environment. Other environments should be studied, but have less data available and are beyond the scope of the work presented in this paper. The debris clouds produced by the NTS tests, frequently called “mushroom clouds,” are familiar, with common structural elements such as a buoyant cap connected to a skirt of raised dust at the desert surface by a thin, dirt-filled stem. The film scanning project at LLNL has investigated historical film records of nuclear weapons tests. Here, we summarize findings showing that the mushroom cloud behavior for historic U.S. tests conducted in Nevada, has similar characteristics based on the distance of the device from the ground surface or Height of Burst (HOB), scaled by the energy release, or yield, of the device. This scaled height is referred to as the scaled-height-of-burst (SHOB). The findings discussed below show that mushroom clouds look and behave similarly when detonated at the same SHOB. The amount of residual radiation that is produced by a nuclear detonation is proportional to the yield. But, the amount of that residual radiation that actually becomes local fallout is strongly dependent on the SHOB and the type of surface over which the detonation occurs. In order to develop a more comprehensive model that predicts the fraction of the residual radiation that becomes local fallout, it is convenient to define a series of regimes based on SHOB values in which all detonations that occur within a given regime can be modeled using the same algorithms. The purpose of this paper is to provide a framework for defining different regimes, and, in a qualitative way, a basic understanding of the fundamental characteristics of each of these regimes.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

Nuclear Weapons and the Atmospheric Test Era

The era of atmospheric testing defies a simple description. Beginning with the goal of proving fission, the United States’ test program grew in complexity as scientists explored thermonuclear reactions, met the military demand for a variety of weapons for an increasing number of delivery platforms, and reacted to the ever-growing public fear of fallout. And, of course, political considerations were always present, first in the prosecution of World War II and later in the Cold War. To understand the atmospheric test program, then, is to understand how science, politics, and the public shaped our society in ways that are still difficult to fully understand.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗