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EPC-ES finds that the materials associated with TA-16-306 (see Figure 1) are candidate for release to the public for recycle or as sanitary/commercial waste.This finding is consistent with the requirements of DOE Order 458.1 Radiation Protection of the Public and the Environment and LANL procedure EPC-ES-FSD-004, Environmental Radiation Protection.
Background: Vacationing at sunny, warm weather locations is a risk factor for excessive solar ultraviolet (UV) radiation exposure and skin cancer. Objectives: This study examined the association of environmental variables related to UV levels with vacationers' sun protection. Methods: Vacationers at 41 summer resorts in 17 states and 1 Canadian Province were interviewed (n=3531) and observed (N=4347) during 2012 and 2013. Clothing coverage, sunglasses, and shade use were observed. Use of sunscreen and sunburns were self-reported. Environmental information was recorded by research staff or acquired from ground stations and the weather service. Results: Temperature was positively associated with sun protection behaviors; however clothing coverage was negatively associated with temperature. Cloud cover was negatively associated with sun protection, with the exception of clothing coverage which was positively associated with it. Elevation showed a mixed pattern of associations with vacationer's sun protection. Latitude of a resort was negatively associated with most sun protection behaviors, such that sun protection increased at more southerly resorts. Similarly, the farther south a vacationer traveled to the resort, the less sun protection they employed. The UV index showed a weak, positive relationship with some sun protection behaviors even when controlling for temperature. Conclusions: Vacationers appeared aware that UV is higher at southern latitudes and may learn UV is intense when living in southern regions. However, many used temperature, an unreliable cue, to judge UV intensity and seemed to adjust clothing for warmth not UV protection. Efforts are needed to help individuals make more accurate sun safety decisions. - Highlights: • Vacationers poorly monitor and protect against environmental ultraviolet radiation (UVR). • On cloudy days vacationers fail to protect against UVR. • Temperature is erroneously used by vacationers as a marker for UVR. • Clothing is used primarily by vacationers for warmth, not UVR protection. • The farther south a vacationer travels, the more likely they are to sunburn.
The evolution of space suit design to meet the needs of past and future manned space missions is discussed. Following a brief consideration of the purposes of the space suit in providing an artificial atmosphere and protection from environmental hazards, attention is given to the first high-altitude suits developed in the 1930's for the protection of balloon pilots, and for high-altitude airplane flights. The Mercury project space suit is presented as essentially similar to those for high-altitude military aircraft developed since World War II, providing pressurization and oxygen as a backup to the capsule systems. Modifications to the suit allowing it to be worn without discomfort during work outside the spacecraft, which were stimulated by experience in Gemini missions, are considered, which culminated in the suits of the Apollo and Skylab programs which provided insulation, cooling and life support for periods of up to eight hours. Finally, changes to suit design made necessary by the increasing numbers of men and women to perform Space Shuttle flights and space construction operations are considered.
The purpose of this paper is to use the Monte Carlo N-Particle Code (MCNP) to investigate the dose from gamma-emitting radionuclides such as Carbon-11 when a plume passes overhead. MCNP results are compared with results from the EPA program, CAP88. In some cases, typically near the source during stable conditions, the CAP88 results are less than the MCNP results. However, in the case of a receptor 800 m from a source at the Los Alamos Neutron Science Center (LANSCE), the CAP88 result is greater than the MCNP result.
The feasibility of heat removal during emergency cooling of a reactor by a forced-draft cooling tower with accumulation of the peak heat release in a volume of precooled water is evaluated. The advantages of a cooling tower over a spray cooling pond are demonstrated: it requires less space, consumes less material, employs shorter lines in the heat removal system, and provides considerably better protection of the environment from wetting by entrained moisture.
The bystander effect, a non-targeted effect (NTE) of radiation, which describes the response by non-irradiated organisms to signals emitted by irradiated organisms, has been documented in a number of fish species. However transgenerational effects of radiation (including NTE) have yet to be studied in fish. Therefore rainbow trout, which were irradiated as eggs at 48 h after fertilisation, eyed eggs, yolk sac larvae or first feeders, were bred to generate a F1 generation and these F1 fish were bred to generate a F2 generation. F1 and F2 fish were swam with non-irradiated bystander fish. Media from explants of F1 eyed eggs, F1 one year old fish gill and F1 two year old fish gill and spleen samples, and F2 two year old gill and spleen samples, as well as from bystander eggs/fish, was used to treat a reporter cell line, which was then assayed for changes in cellular survival/growth. The results were complex and dependent on irradiation history, age (in the case of the F1 generation), and were tissue specific. For example, irradiation of one parent often resulted in effects not seen with irradiation of both parents. This suggests that, unlike mammals, in certain circumstances maternal and paternal irradiation may be equally important. This study also showed that trout can induce a bystander effect 2 generations after irradiation, which further emphasises the importance of the bystander effect in aquatic radiobiology. Given the complex community structure in aquatic ecosystems, these results may have significant implications for environmental radiological protection. - Highlights: • We evaluated the transgenerational effect of early life irradiation in rainbow trout. • Trout irradiated as eggs, yolk sac larvae or first feeders were crossed. • A transgenerational effect was evident in two generations after irradiation. • F1 and F2 generation fish induced a bystander effect in non-irradiated fish. • The precise effects were tissue specific and dependent on parental radiation history.
Accurate surface temperature-mapping capabilities in the 1300 to 1500 °C range are needed for SiC/SiC ceramic matrix composites protected by environmental barrier coatings (EBCs) under testing in turbine engine environment facilities. The strong background thermal radiation at these higher temperatures is a challenging issue. Er-doped Y 2 SiO 5 was previously shown to be capable of achieving luminescence lifetime-based temperature mapping up to 1560 °C as a standalone material. However, compatibility issues between an Er-doped Y 2 SiO 5 surface temperature sensing layer and an underlying Sc 2 Si 2 O 7 -based EBC topcoat limited temperature mapping of the EBC surface to a maximum of 1380 °C. Therefore, an Er-doped Sc 2 SiO 5 temperature sensing layer has been subsequently developed with better compatibility with the Sc2Si2O7-based EBC topcoat. Localized spot temperature measurements as well as luminescence lifetime imaging-based temperature mapping were demonstrated up to 1535 °C from a 15 µm thick Er-doped Sc 2 SiO 5 layer at the surface of a Sc2Si2O7-based EBC topcoat, a significant improvement over the Er-doped Y2SiO5 layer 1380 °C temperature sensing limit. No degradation of the Er-doped Sc 2 SiO 5 temperature sensing surface layer was observed.
The Antarctic photopsychrophile, Chlamydomonas priscui UWO241, is adapted to extreme environmental conditions, including permanent low temperatures, high salt, and shade. During long-term exposure to this extreme habitat, UWO241 appears to have lost several short-term mechanisms in favor of constitutive protection against environmental stress. This study investigated the physiological and growth responses of UWO241 to high-light conditions, evaluating the impacts of long-term acclimation to high light, low temperature, and high salinity on its ability to manage short-term photoinhibition. We found that UWO241 significantly increased its growth rate and photosynthetic activity at growth irradiances far exceeding native light conditions. Furthermore, UWO241 exhibited robust protection against short-term photoinhibition, particularly in photosystem I. Lastly, pre-acclimation to high light or low temperatures, but not high salinity, enhanced photoinhibition tolerance. These findings extend our understanding of stress tolerance in extremophilic algae. In the past 2 decades, climate change-related increasing glacial stream flow has perturbed long-term stable conditions, which has been associated with lake level rise, the thinning of ice covers, and the expansion of ice-free perimeters, leading to perturbations in light and salinity conditions. Our findings have implications for phytoplankton survival and the response to change scenarios in the light-limited environment of Antarctic ice-covered lakes.
The International Commission on Radiological Protection (ICRP) Task Group 120 (TG120) is developing ICRP recommendations for radiological protection for a wide range of radiation accidents and malicious events, complementing those given in ICRP Publication 146 (2020) for large nuclear accidents. The scope includes accidents involving criticalities, operating faults, and fires and explosions in nuclear facilities, inadvertent damage to sealed radiation sources, as well as malicious events, such as sabotage of nuclear facilities or materials, use of radiological dispersal devices, the contamination of food and drinking water supplies, and the deployment of nuclear weapons. A template has been designed to collate relevant information on a wide range of case studies and hypothetical malicious scenarios to ensure that the recommendations developed are broadly applicable and comprehensive. For all scenarios, a graded approach to protection is being taken, accepting that specific guidance may be required for some distinctive aspects, for example, protection during times of armed conflict. This paper provides an overview of the scenarios and scope of the work of TG120, including some of the radiological and non-radiological impacts of radiation emergencies, along the response and recovery timeline.
The licensing process for any facility associated with nuclear power or aspects of the nuclear fuel cycle can be expected to encounter intense stakeholder interest, and often significant challenges. Over the last decade, staff of the Center for Nuclear Waste Regulatory Analyses (CNWRA{sup R}) at Southwest Research Institute{sup R} (SwRI{sup R}) provided comprehensive support to the U.S. Nuclear Regulatory Commission (NRC) for public outreach efforts across a wide variety of nuclear activities. Many of these projects included public involvement and consultation activities for compliance with the National Environmental Policy Act (NEPA), including scoping, public meetings, responding to public comments on draft documents, and holding small meetings with affected local, state, and tribal governments. In addition, we have supported NRC public outreach related to nuclear facility licensing activities (including the proposed repository at Yucca Mountain), rulemaking, and regulatory guidance development. This experience has offered us a broad view of the challenges faced by industry, regulators, and stakeholders. In the process, we have observed some best practices that lead to effective stakeholder communication. Communication about complex technical issues is challenging, particularly for societally controversial topics, such as civilian use of nuclear power and management of radioactive waste. Most commonly, we have observed a lack of mutual trust and respect among industry, regulators, and stakeholders that creates an atmosphere ripe for suspicion and misunderstanding. Stakeholders have, in public comments, criticized the lack of appropriate venues to raise concerns in which they feel they can get meaningful responses from the nuclear industry and regulators. Conversely, industry faces difficulty in reaching compromise with stakeholders, who sometimes misinterpret or misrepresent factual information. Within this contentious environment, regulators are constrained by their statutory framework, even as they are challenged to be more responsive, transparent, and fair to both stakeholders and industry. In spite of these obstacles, there are examples where feedback from stakeholders was heard and utilized. Because of successful collection of appropriate feedback, regulators became more adept at understanding the full range of perspectives from both industry and stakeholders, and subsequently did a better job at effectively incorporating feedback and communicating their decisions and findings in a clear and understandable way. Ultimately, the success of these examples was based on a measure of mutual respect, which was reached through effective communication and implementation of some best practices. These best practices include (i) outreach planning that is abundantly mindful of the various stakeholder points of view, site history, regional characteristics, and probable future and related actions, combined with advance identification of key stakeholders; (ii) development and distribution of information that facilitates public participation; and (iii) use of avenues by which stakeholders can provide meaningful and effective comments. Illustrative examples include (i) how concerns raised by stakeholders were heard by an applicant and resulted in a revised project proposal; (ii) use of a variety of interaction formats that incorporated input across a broad spectrum of stakeholders; (iii) utilizing stakeholder feedback received during scoping; and (iv) how a facility underestimated the impact of 'outsider' stakeholder voices that were in contrast to the known local community. By moving past the viewpoint that public outreach is a 'necessary evil' and engaging only to check a procedural box, each participant can benefit from mutually satisfactory and improved outcomes. (author)
The world’s oceans are a global reservoir of persistent organic pollutants to which humans and other animals are exposed. Although it is well known that these pollutants are potentially hazardous to human and environmental health, their impacts remain incompletely understood. We examined how persistent organic pollutants interact with the drug efflux transporter P-glycoprotein (P-gp), an evolutionarily conserved defense protein that is essential for protection against environmental toxicants. We identified specific congeners of organochlorine pesticides, polychlorinated biphenyls, and polybrominated diphenyl ethers that inhibit mouse and human P-gp, and determined their environmental levels in yellowfin tuna from the Gulf of Mexico. In addition, we solved the cocrystal structure of P-gp bound to one of these inhibitory pollutants, PBDE (polybrominated diphenyl ether)–100, providing the first view of pollutant binding to a drug transporter. The results demonstrate the potential for specific binding and inhibition of mammalian P-gp by ubiquitous congeners of persistent organic pollutants present in fish and other foods, and argue for further consideration of transporter inhibition in the assessment of the risk of exposure to these chemicals.
The purpose of this charter is to establish, maintain, and implement programs for the protection, preservation, and enhancement of the land and water resources of Los Alamos National Laboratory in a changing climate.
The mission of Los Alamos National Laboratory (the Laboratory) is to solve national security challenges through scientific excellence. Our vision is delivering science and technology to protect our nation and promote world stability.
Mitigation of flammability concerns within Hanford waste tanks is essential to Safe Storage and Waste Feed Delivery sub-functions of the River Protection Project Mission. The tanks that have a higher propensity for the generation, retention, and release of flammable gas are considered Waste Group A tanks. Group A tanks include 241-SY-103, 241-AN-103, 241-AN-104, 241-AN-105, and 241-AW-101. Successful mitigation of flammability concerns in these tanks is necessary, as they are critical to the completion of the River Protection Project Mission as indicated in the Integrated Waste Feed Delivery Plan. The benchmark for examination of tank flammability issues is 241-SY-101. Studies of Tank 241-SY-101 gas release events showed that the mechanism of gas retention and release was highly dependent on the volume and configuration of a floating crust layer. Beginning in 1993, 241-SY-101 underwent water additions and mixer pump operations resulting in dissolution of the crust. These efforts mitigated the flammability concerns of the tank. A similar mitigation approach was recommended for Tank 241-SY103 and is recommended for the other Waste Group A tanks. However, this recommended mitigation will be more or less effective based on the expected thickness of the crust present in each of the Group A tanks. Considerations of flammable gas generation and release mechanisms were essential in the development of a successful mitigation strategy for Tank 241-SY-101, and will be essential in the development of future mitigation strategies. Because crust properties are difficult to measure, tank surface level trends and current temperature profiles are evaluated to understand crust properties. 241-AN-103 and 241-AW-101 are the only two tanks with a net increase in surface level, indicating a higher generation and retention of flammable gas. Additionally, these are the two tanks with the thickest crusts, which causes both a higher retention of gas and a reduced evaporation rate. Given the current temperature profile, crust thickness for 241-AW-101 was re-evaluated to be 145 cm (57 in) ± 30 cm (12 in) which is different from its historic value. This gives 241-AW-101 the thickest crust, second only to 241-SY-101 prior to mitigation. The crust thickness for 241-AN-103, however, retains its historic value of 89 cm (35 in) ± 16 cm (6 in). These crust properties suggest modifications to the mitigation strategy are needed for each tank. For example, 241-AN-103 and 241-AW-101 will require additional water to dissolve the crust layer before flammability concerns are mitigated and further operations could commence. Implementation of the modified mitigation strategies will mitigate flammability issues and help fulfill the Safe Storage and Waste Feed Delivery sub-functions of the River Protection Project Mission safely and efficiently. (authors)
With radon and its daughter products estimated as the second leading cause of lung cancer in the United States, it is imperative to understand their relative equilibrium inside commercial, community, and residential dwellings. The radon indoor inhalation fractional equilibrium factor (F eq ) quantifies the disequilibrium between radon and its progeny in indoor air, and recent advances have shown how air exchange rates (ACH) influence F eq . These numerically derived ACH-dependent F eq values are incorporated into the U.S. EPA's Radon Vapor Intrusion Screening Level (RVISL) calculator, which assists risk assessors in evaluating radon exposure. To advance the risk assessment science of actinon (Rn-219), thoron (Rn-220), and radon (Rn-222), the impact of variables such as indoor aerosol concentration and composition, outdoor air quality, household-specific characteristics, and environmental/meteorological conditions on the F eq must be examined. The primary objective of this research is to analyze these additional variables to determine the usefulness of incorporating such adjustment factors into the RVISL calculator and to identify areas of future research. Studies regarding the influence of these parameters are presented along with recommendations regarding the adjustment of the numerically derived F eq value. For example, elevated indoor aerosol concentrations, such as those originating from outdoor PM 2.5 or cigarette smoke, increase the abundance of accumulation- mode particles indoors, which in turn raises F eq values by facilitating the attachment of radon progeny to these aerosols. Smoking increases both the bronchial dose and F eq , while regions with high smog levels demonstrate the impact of regional air quality on F eq . In contrast, air cleaning systems and purifiers have been shown to reduce the F eq , suggesting that these systems could help mitigate radon exposure. Additionally, higher F eq values are typically observed during winter when ventilation rates are lower. This paper presents adjustment factors that may be applied to the RVISL F eq , emphasizing the need for further research to refine these variables and ensure accurate risk assessments in diverse environments. Applying these adjustment factors will minimize calculator over- and underestimations, providing a more accurate representation of the real-world risk associated with radon.
Luminescence lifetime-based temperature mapping for thermal barrier coatings (TBCs) has been previously demonstrated up to temperatures approaching 1200 °C. Advantages of this method include insensitivities to reflected radiation and emissivity uncertainties. Because of a push towards greater efficiency turbine engine operation using higher turbine inlet temperatures, there is an ongoing movement from TBC-coated superalloy turbine engine components to SiC/SiC ceramic matrix composite components protected by environmental barrier coatings (EBCs). The useful application of luminescence lifetime-based temperature mapping to EBCs requires a significant increase in high temperature capability from below 1200 °C up into the 1300 to 1500 °C temperature range where the much higher background thermal radiation is a challenging issue. In addition, the luminescing sensing layer must exhibit thermochemical compatibility with the EBC. To meet these requirements, Er-doped Y 2 SiO 5 was selected as the luminescing sensor layer material both for its enhanced temperature sensitivity above 1300 °C and its compatibility with rare-earth disilicate EBC topcoats. Both localized spot temperature measurements as well as luminescence lifetime imaging-based temperature mapping were demonstrated up to 1560 °C for Er-doped Y 2 SiO 5 disks. In addition, temperature mapping capability was demonstrated from a 15 µm thick Er-doped Y 2 SiO 5 layer at the surface of a Sc 2 Si 2 O 7 based EBC topcoat. Both localized spot and temperature mapping by luminescence lifetime imaging were demonstrated up to 1380 °C (upper temperature limit of this slurry-based layered EBC) with excellent suppression of background thermal radiation and no degradation of the Er-doped Y 2 SiO 5 temperature sensing surface layer. The source of the novel enhanced temperature sensitivity above 1300 °C will be discussed as well as a path towards compatibility between sensing layer and EBC topcoat to higher temperatures.
These are the slides of a meeting about trails at Los Alamos National Laboratory. The meeting goals are the folllowing: to inform and educate citizens about LANL trails management issues that include resource protection, safety, security and trails etiquette; to explain how and why LANL trails can be closed and reopened; and to understand your concerns and ideas about LANL trails use.
Highlights: • First paper on the importance of incineration from a urban metabolism point of view. • Proves that incineration is necessary for sustainable waste management. • Historical and technical overview of 100 years development of MSW incineration. - Abstract: Human activities inevitably result in wastes. The higher the material turnover, and the more complex and divers the materials produced, the more challenging it is for waste management to reach the goals of “protection of men and environment” and “resource conservation”. Waste incineration, introduced originally for volume reduction and hygienic reasons, went through a long and intense development. Together with prevention and recycling measures, waste to energy (WTE) facilities contribute significantly to reaching the goals of waste management. Sophisticated air pollution control (APC) devices ensure that emissions are environmentally safe. Incinerators are crucial and unique for the complete destruction of hazardous organic materials, to reduce risks due to pathogenic microorganisms and viruses, and for concentrating valuable as well as toxic metals in certain fractions. Bottom ash and APC residues have become new sources of secondary metals, hence incineration has become a materials recycling facility, too. WTE plants are supporting decisions about waste and environmental management: They can routinely and cost effectively supply information about chemical waste composition as well as about the ratio of biogenic to fossil carbon in MSW and off-gas.