Department Of Energy Facilities Research Articles

AI-based detection and identification of low-level nuclear waste: a comparative analysis

Ensuring environmental safety and regulatory compliance at Department of Energy (DOE) sites demands an efficient and reliable detection system for low-level nuclear waste (LLW). Unlike existing methods that rely on human effort, this paper explores the integration of computer vision algorithms to automate the identification of such waste across DOE facilities. We evaluate the effectiveness of multiple algorithms in classifying nuclear waste materials and their adaptability to newly emerging LLW. Our research introduces and implements five state-of-the-art computer vision models, each representing a different approach to the problem. Through rigorous experimentation and validation, we evaluate these algorithms based on performance, speed, and adaptability. The results reveal a noteworthy trade-off between detection performance and adaptability. YOLOv7 shows the best performance and requires the highest effort to detect new LLW. Conversely, OWL-ViT has lower performance than YOLOv7 and requires minimal effort to detect new LLW. The inference speed does not strongly correlate with performance or adaptability. These findings offer valuable insights into the strengths and limitations of current computer vision algorithms for LLW detection. Each developed model provides a specialized solution with distinct advantages and disadvantages, empowering DOE stakeholders to select the algorithm that aligns best with their specific needs.

Modification in Applying Appendix D of 40 CFR Part 61 to Heated Solid Radionuclide Materials With High Melting and Boiling Points.

Appendix D of Title 40 Part 61 of the US Code of Federal Regulations (CFR) provides a procedure that US Department of Energy (US DOE) facility owners and operators can use to estimate radionuclide emissions to the atmosphere for dose calculations instead of measuring emissions for minor sources under the 40 CFR Part 61, Subpart H, National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities, regulation. The procedure assumes that any radioactive material heated above 100 °C is completely vaporized and emitted to the atmosphere. In 1991, the US DOE Oak Ridge Reservation (ORR) requested approval to use different release fractions (RFs) for uranium because of its high melting and boiling points. In response to the request, the US Environmental Protection Agency (US EPA) Region IV approved the use of modified RFs for elemental uranium provided no reaction had taken place to alter its chemical form. In 2015, the ORR requested approval to use different RFs for tungsten, again because of its high melting and boiling points. EPA Region IV approved the use of modified RFs for heated radioactive tungsten metal. In accordance with the two precedents set for heating uranium and radioactive tungsten metals, in 2016, the ORR requested approval to use modified RFs in a similar fashion for other radioactive solid metals and compounds with melting and boiling points above 500 °C that might be heated above 100 °C in future research projects and experiments. EPA Region IV again granted approval to use modified RFs for the list of compounds. This note discusses the proposed modified RFs and their development.

Methods to Account for CAP-88 PC-Omitted Nuclides in Radioactive Air Emissions From DOE Facilities.

Routine research and development activities at US Department of Energy facilities can result in the release of radioactive emissions, potentially exposing the public and the environment. Such emissions are subject to certain Clean Air Act regulations, specifically those outlined in 40 CFR Part 61, Subpart H, which are enforced by the US Environmental Protection Agency. Compliance is determined in part with a dose standard. Doses to members of the public from most US Department of Energy facility airborne emissions are modeled using CAP-88 PC software, the latest version of which contains more than 1,200 radionuclides. Radioactive effluents from US Department of Energy facilities may contain radioisotopes that are not available in CAP-88 PC, and those radioisotopes must still be evaluated to determine whether doses to members of the public are below established limits. CAP-88 PC-omitted radionuclides can be accounted for using alternate methods, including the use of surrogate radionuclides. This paper elucidates the process of accounting for CAP-88 PC-omitted radionuclides by providing criteria and rationale for surrogate selection, a compilation of surrogate radionuclides used in the past by US Department of Energy facilities, a discussion of alternate methods used to account for CAP-88 PC-omitted radionuclides and a comparison of methods and impacts on receptor doses. Ultimately, this paper aims to aid in the process of surrogate selection and consequently to simplify and expedite compliance with Clean Air Act regulations.

The dynamic nature of risk in DOE facilities in the surveillance and maintenance program-with observations for risk communications.

We explore three case studies of facilities at two US Department of Energy (DOE) former nuclear weapons research and production sites-the Oak Ridge National Laboratory and the Hanford site-whose risk profiles have changed during their long-term management under the DOE's surveillance and maintenance (S&M) program. These case studies provide examples of the challenges faced in communicating to external stakeholders, such as federal and state regulators, local communities surrounding the site, as well as the general public, the circumstances surrounding unexpected events or the emergence/discovery of new risk-important information at historically high-risk sites. We identify common topics of importance from these case studies and suggest a taxonomy for risk communicators to use in informing the dialogues with individuals and organizations that may not be technically oriented or fully informed on the subject matter. The taxonomy is based on technical insights from the quintessential definition of risk known as the Kaplan-Garrick "risk triplet" as well as insights from regulatory guidance documents on risk communication with external stakeholders originally developed for the commercial nuclear power industry.

Boiling sand, metallic fire

ABSTRACTIn April 2018 four drums of depleted uranium sludge burst open at a US Department of Energy facility at Idaho National Laboratory. This echoed a previous incident in 2014, when a drum erupted with fire and spewed radionuclides at a nuclear waste repository in New Mexico. Such “drum breach” accidents have been characterized in official reports as “isolated events,” and as “self‐initiated” and “spontaneous.” Yet these descriptions misrepresent a temporal tension at the heart of their causation: during the Cold War, nuclear weapons production created latent socioecological hazards that, decades later, too often manifest during waste cleanup. This tends to result from 21st‐century scheduling pressures, fraught labor relationships, and neoliberal subcontracting arrangements. Thus, if we examine the temporal form taken by US nuclear technopolitics, we can recast drum breach accidents not as stand‐alone events, but as outcomes of systemic incentives to speed up waste‐cleanup projects beyond their organizational capacity without commensurately expanding their safety or oversight mechanisms. [nuclear waste, technopolitics, accidents, neoliberalism, temporality, security, Idaho, United States]

Worker Trainers as Workplace Experts: How Worker Trainers Enhance Safety and Health at Department of Energy Facilities

Worker trainers not only teach health and safety in the classroom setting but also serve informally as important peer resources on the shop floor. They are often the "go to" people, for both hourly workers and managers, when there is a health or safety question-be it about tank vapors or personal protective equipment, confined space, or specific chemicals. These worker trainers actively use health and safety resource materials, both hard copy and online. Documented here, through two surveys of worker trainers-at U.S. Department of Energy facilities, trained through the International Chemical Workers Union Council Consortium of the Worker Training Program of the National Institute of Environmental Health Sciences-is documentation of this additional contribution that worker trainers make toward safer and more healthful work places.

Use of carbon stable isotopes to monitor biostimulation and electron donor fate in chromium-contaminated groundwater

Hexavalent chromium Cr(VI) is a common inorganic contaminant in industrial areas and represents a serious threat to human health due its toxicity. Here we report experimental results from a field-scale investigation of Cr(VI) bio-immobilization at Hanford 100H reservation, a U.S Department of Energy facility (Washington State, USA). Microbial Cr(VI) reduction was stimulated via injection of a13C-labeled sodium lactate solution into the high-permeability aquifer consisting of gravel and coarse sand sediments. Concentrations and carbon isotope ratios of metabolites, including dissolved inorganic carbon and total organic carbon, and compound-specific analysis of acetate and propionate, together with phospholipid fatty acids (biomass) have been analyzed to help provide an understanding of the predominant redox processes accompanying Cr(VI) reduction. Results of our study indicate that the injection of an electron donor caused a sharp decrease of Cr(VI) concentration from ∼32 to ∼10 nM. Cr(VI) reduction was associated with a decrease in the concentration of carboxylic acids, such as lactate (∼6 mM to undetectable), propionate (∼9 mM to undetectable), and acetate (∼6 mM to undetectable), as well as dissolved inorganic carbon (30–10 mM C). Carbon isotope data indicate carbon transfers from the original substrate to organic byproducts and mineralized carbon. Concentrations of metabolites and stable isotope data as well as carbon isotope mass balance calculations were used to monitor biologically mediated reduction of Cr(VI).

Design of concrete walls and slabs for wind-borne missile loadings

Exterior walls and roofs in safety-related nuclear facilities in the United States, including nuclear power plants, must be designed to resist the loadings imposed by missiles (steel pipes, steel spheres, automobiles) borne by hurricanes and tornadoes. For confinement or containment, these walls and roofs are constructed from reinforced and/or prestressed concrete. The minimum required thicknesses of a reinforced panel to prevent scabbing and perforation for an impacting steel pipe are typically established using empirical formulae calibrated for rigid missiles and high velocities. To enable improved design of concrete panels to prevent scabbing and perforation by wind-borne steel pipes, numerical simulations were performed to: (1) investigate the effects of panel thickness, pipe mass and diameter, pipe velocity, and concrete uniaxial compressive and tensile strength on impact resistance, and (2) establish minimum panel thicknesses to prevent scabbing and perforation for the pipes and impact velocities specified in standards of practice. The numerical simulations used axisymmetric SPH models validated using data from tests at Sandia National Laboratory in the 1970s of four reinforced concrete panels impacted by Schedule 40 pipes. The values of panel thickness and concrete compressive strength considered in the parametric study are typical of those in existing nuclear power plant structures in the United States. The Schedule 40 pipe is the missile used for simulations because it is referenced in the United States Nuclear Regulatory Commission (USNRC) Standard Review Plan and the Department of Energy (DOE) Natural Phenomena Hazards Analysis and Design Criteria for DOE Facilities that point to Regulatory Guide (RG) 1.76, RG 1.221, and ANS-2.3. The impact velocities bound the maximum velocities recommended in the USNRC and ANS documents for design against the impact of Schedule 40 pipes. A considerable number of design parameters have a meaningful effect on the impact resistance of reinforced concrete panels but the most important, aside from panel thickness and impact velocity, is tensile strength of concrete. Results of the parametric study enable the writing of guidance on the minimum thickness of reinforced concrete panels to resist 152 mm (6 in), 203 mm (8 in) and 254 mm (10 in) diameter Schedule 40 pipes at impact velocities identified in RG 1.76, RG 1.221 and ANS-2.3. Panel thickness ranging from 305 mm (12 in) to 914 mm (36 in) are required to prevent perforation and scabbing caused by the impact of these Schedule 40 pipes. The required panel thickness decreases with increasing tensile strength.

Oak Ridge Reservation Environmental Protection Rad Neshaps Radionuclide Inventory Web Database and Rad Neshaps Source and Dose Database.

The U.S. Environmental Protection Agency promulgated national emission standards for emissions of radionuclides other than radon from US Department of Energy facilities in Chapter 40 of the Code of Federal Regulations (CFR) 61, Subpart H. This regulatory standard limits the annual effective dose that any member of the public can receive from Department of Energy facilities to 0.1 mSv. As defined in the preamble of the final rule, all of the facilities on the Oak Ridge Reservation, i.e., the Y-12 National Security Complex, Oak Ridge National Laboratory, East Tennessee Technology Park, and any other U.S. Department of Energy operations on Oak Ridge Reservation, combined, must meet the annual dose limit of 0.1 mSv. At Oak Ridge National Laboratory, there are monitored sources and numerous unmonitored sources. To maintain radiological source and inventory information for these unmonitored sources, e.g., laboratory hoods, equipment exhausts, and room exhausts not currently venting to monitored stacks on the Oak Ridge National Laboratory campus, the Environmental Protection Rad NESHAPs Inventory Web Database was developed. This database is updated annually and is used to compile emissions data for the annual Radionuclide National Emission Standards for Hazardous Air Pollutants (Rad NESHAPs) report required by 40 CFR 61.94. It also provides supporting documentation for facility compliance audits. In addition, a Rad NESHAPs source and dose database was developed to import the source and dose summary data from Clean Air Act Assessment Package-1988 computer model files. This database provides Oak Ridge Reservation and facility-specific source inventory; doses associated with each source and facility; and total doses for the Oak Ridge Reservation dose.

Location Modification Factors for Potential Dose Estimation.

A U.S. Department of Energy facility must comply with the National Emission Standard for Hazardous Air Pollutants for radioactive air emissions. The standard is an effective dose of less than 0.1 mSv y to the maximum public receptor. Additionally, a lower dose level may be assigned to a specific emission point in a State issued permit. A method to efficiently estimate the expected dose for future emissions is described. This method is most appropriately applied to a research facility with several emission points with generally low emission levels of numerous isotopes.

The effect of environmental remediation on the cesium-137 levels in white-tailed deer.

Due to activities involving nuclear energy research during the latter half of the 1900 s, environmental contamination in the form of elevated cesium-137 levels was observed within the Brookhaven National Laboratory, a US Department of Energy facility. Between the years 2000 and 2005, the laboratory carried out a major soil cleanup effort to remove cesium-137 from contaminated sites. In this study, we examine the effectiveness of the cleanup effort by comparing the levels of cesium-137 in the meat of white-tailed deer found within and around the laboratory. Results suggest that the cleanup was effective, with mean concentration of cesium-137 in the meat from within the laboratory decreasing from 2.04 Bq/g prior to 1.22 Bq/g after cleanup. At the current level, the consumption of deer would not pose any human health hazard. Nevertheless, statistically higher levels of cesium-137 were detected in the deer within the laboratory as opposed to levels found in deer 1 mi beyond the laboratory site.

Characterization of Exposures to Workers Covered Under the U.S. Energy Employees Compensation Act

Since the mid-1940s, hundreds of thousands of workers have been engaged in nuclear weapons-related activities for the U.S. Department of Energy (DOE) and its predecessor agencies. In 2000, Congress promulgated the Energy Employees Occupational Illness Compensation Program Act of 2000 (EEOICPA), which provides monetary compensation and medical benefits to certain energy employees who have developed cancer. Under Part B of EEOICPA, the National Institute for Occupational Safety and Health (NIOSH) is required to estimate radiation doses for those workers who have filed a claim, or whose survivors have filed a claim, under Part B of the Act. To date, over 39,000 dose reconstructions have been completed for workers from more than 200 facilities. These reconstructions have included assessment of both internal and external exposure at all major DOE facilities, as well as at a large number of private companies [known as Atomic Weapons Employer (AWE) facilities in the Act] that engaged in contract work for the DOE and its predecessor agencies. To complete these dose reconstructions, NIOSH has captured and reviewed thousands of historical documents related to site operations and worker/workplace monitoring practices at these facilities. Using the data collected and reviewed pursuant to NIOSH's role under EEOICPA, this presentation will characterize historical internal and external exposures received by workers at DOE and AWE facilities. To the extent possible, use will be made of facility specific coworker models to highlight changes in exposure patterns over time. In addition, the effects that these exposures have on compensation rates for workers are discussed.Introduction of Characterization of Exposures to Workers (Video 1:59, http://links.lww.com/HP/A3).

A Best Fit Approach to Estimating Multiple Diffuse Source Terms Using Ambient Air Monitoring Data and an Air Dispersion Model

Lawrence Livermore National Laboratory uses CAP88-PC Version 1.0 modeling software to demonstrate compliance with the Code of Federal Regulations Title 40 Part 61 Subpart H (National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities). Annual air emissions from both well characterized stack sources and difficult to characterize diffuse sources must be assessed. This paper describes a process that uses a mathematical optimization routine to find a set of estimated diffuse source terms that together with the measured stack source terms provides a best fit of modeled air concentrations to measured air concentrations at available sampling locations. The estimated and measured source terms may then be used in subsequent CAP88-PC modeling to estimate dose at the off-site maximally exposed individual. LLNL has found this process to be an effective way to deal with the required assessment of diffuse sources that have otherwise been difficult to assess.

Psychosocial Effects of Beryllium Sensitization and Chronic Beryllium Disease

The objective of this research was to describe the psychosocial effects of beryllium sensitization (BeS) and chronic beryllium disease (CBD) for a sample of current and former workers from U.S. Department of Energy facilities in Oak Ridge, TN. Semi-structured interviews were conducted with 13 participants. Interviews were recorded and transcribed. The responses were coded and analyzed to identify patterns and themes and to learn about their experiences. The results were compared to a theoretical model developed by the authors. Participants described ambiguity, inconsistency, vagueness, unpredictability, lack of information, and unfamiliarity that was consistent with the Michel Uncertainty in Illness Scale. They also described how they adjusted to their illness in a manner aligned with Derogatis’ Psychosocial Adjustment to Illness theory. Based on the results of this study, it appears appropriate to apply Uncertainty in Illness and Psychosocial Adjustment to Illness theories to BeS and CBD. Uncertainty may be considered an independent variable and psychosocial adjustment an intermediate variable in the study of the psychosocial effects of BeS and CBD.

Unknown Quantity: Regulating Radionuclides in Tap Water

Radioactivity surrounds us; each day we are exposed to a certain amount by virtue of being alive on planet Earth. Some of this exposure comes from radioactive substances (radionuclides) that occur naturally in a wide variety of geologic and soil formations. Occasionally these naturally occurring substances become more concentrated or accessible through human activities such as mining and nuclear energy production, resulting in greater potential for exposure than their original natural occurrence would suggest. Other radionuclides are artificially created. Residents in almost all parts of the United States live on lands that contain minor to substantial concentrations of radionuclides of one type or another.1 These substances often make their way into tap water, leading to exposures by ingestion, inhalation, or dermal pathways during showering or other contact with the water. Although radionuclides are widespread, there are large gaps in our knowledge about sources of these materials, their distribution, associated health risks, and mitigation measures. However, the information we do have suggests that current drinking water standards for radionuclides established by the U.S. Environmental Protection Agency (EPA) may not adequately protect health. The EPA is set to review these standards relatively soon, and the next two years are prime time for filling in numerous information gaps and doing other legwork to make sure the review is as well informed as possible.

Regulatory experience in applying a radiological environmental protection framework for existing and planned nuclear facilities

Frameworks and methods for the radiological protection of non-human biota have been evolving rapidly at the International Commission on Radiological Protection and through various European initiatives. The International Atomic Energy Agency has incorporated a requirement for environmental protection in the latest revision of its Basic Safety Standards. In Canada, the Canadian Nuclear Safety Commission has been legally obligated to prevent unreasonable risk to the environment since 2000. Licensees have therefore been meeting generic legal requirements to demonstrate adequate control of releases of radioactive substances for the protection of both people and biota for many years. In the USA, in addition to the generic requirements of the Environmental Protection Agency and the Nuclear Regulatory Commission, Department of Energy facilities have also had to comply with specific dose limits after a standard assessment methodology was finalised in 2002. Canadian regulators developed a similar framework for biota dose assessment through a regulatory assessment under the Canadian Environmental Protection Act in the late 1990s. Since then, this framework has been applied extensively to satisfy legal requirements under the Canadian Environmental Assessment Act and the Nuclear Safety and Control Act. After approximately a decade of experience in applying these methods, it is clear that simple methods are fit for purpose, and can be used for making regulatory decisions for existing and planned nuclear facilities.

Geochemical Processes Governing the Fate and Transport of Chromium(III) and Chromium(VI) in Soils

Chromium has served as an exceptional and necessary elemental component of many industrial processes and consumer products. Its prevalence in the global environment as both a dissolved and wind‐borne constituent has prompted concern during the last several decades due to the large migration potential and biological toxicity of various Cr chemical species. The objective of this study was to develop an improved understanding and predictive capability of the rates and mechanisms of competing geochemical redox and sorption reactions that govern the fate and transport of Cr(III) and C(VI) in heterogeneous subsurface environments. Batch and miscible displacement experiments, coupled with solid‐phase spectroscopy methods, were utilized to quantify the interaction of Cr with subsurface materials acquired from three geographically distinct locations within the continental United States that represented soils from different Department of Energy facilities known to have issues regarding Cr contamination. Soil chemical and mineralogical properties were found to be important factors controlling the mechanisms of Cr–solid phase interactions, with many of the reactive processes being time dependent. Both sorption and redox reactions impacted Cr(III)– and Cr(VI)–solid phase interactions and were modeled as nonlinear, nonequilibrium or equilibrium, reversible or nonreversible reactive processes. The research investigations within this study highlight the environmental significance of Cr speciation and solid‐phase reactivity in heterogeneous subsurface soil systems with contrasting geochemical and mineralogical properties.

Long-Term Biological Monitoring of an Impaired Stream: Synthesis and Environmental Management Implications

The long-term ecological recovery of an impaired stream in response to an industrial facility's pollution abatement actions and the implications of the biological monitoring effort to environmental management is the subject of this special issue of Environmental Management. This final article focuses on the synthesis of the biological monitoring program's components and methods, the efficacy of various biological monitoring techniques to environmental management, and the lessons learned from the program that might be applicable to the design and application of other programs. The focus of the 25-year program has been on East Fork Poplar Creek, an ecologically impaired stream in Oak Ridge, Tennessee with varied and complex stressors from a Department of Energy facility in its headwaters. Major components of the long-term program included testing and monitoring of invertebrate and fish toxicity, bioindicators of fish health, fish contaminant accumulation, and instream communities (including periphyton, benthic macroinvertebrate, and fish). Key parallel components of the program include water chemistry sampling and data management. Multiple lines of evidence suggested positive ecological responses during three major pollution abatement periods. Based on this case study and the related literature, effective environmental management of impaired streams starts with program design that is consistent across space and time, but also adaptable to changing conditions. The biological monitoring approaches used for the program provided a strong basis for assessments of recovery from remedial actions, and the likely causes of impairment. This case study provides a unique application of multidisciplinary and quantitative techniques to address multiple and complex regulatory and programmatic goals, environmental stressors, and remedial actions.

Long-Term Water-Quality Changes in East Fork Poplar Creek, Tennessee: Background, Trends, and Potential Biological Consequences

We review long-term changes that have occurred in factors affecting water quality in East Fork Poplar Creek (EFPC; in East Tennessee) over a nearly 25-year monitoring period. Historically, the stream has received wastewaters and pollutants from a major United States Department of Energy (DOE) facility on the headwaters of the stream. Early in the monitoring program, EFPC was perturbed chemically, especially within its headwaters; evidence of this perturbation extended downstream for many kilometers. The magnitude of this perturbation, and the concentrations of many biologically significant water-quality factors, has lessened substantially through time. The changes in water-quality factors resulted from a large number of operational changes and remedial actions implemented at the DOE facility. Chief among these were consolidation and elimination of many effluents, elimination of an unlined settling/flow equalization basin, reduction in amount of blow-down from cooling tower operations, dechlorination of effluents, and implementation of flow augmentation. Although many water-quality characteristics in upper EFPC have become more similar to those of reference streams, conditions remain far from pristine. Nutrient enrichment may be one of the more challenging problems remaining before further biological improvements occur.

Monitoring Fish Contaminant Responses to Abatement Actions: Factors that Affect Recovery

Monitoring of contaminant accumulation in fish has been conducted in East Fork Poplar Creek (EFPC) in Oak Ridge, Tennessee since 1985. Bioaccumulation trends are examined over a twenty year period coinciding with major pollution abatement actions by a Department of Energy facility at the stream's headwaters. Although EFPC is enriched in many contaminants relative to other local streams, only polychlorinated biphenyls (PCBs) and mercury (Hg) were found to accumulate in the edible portions of fish to levels of human health concern. Mercury concentrations in redbreast sunfish were found to vary with season of collection, sex and size of individual fish. Over the course of the monitoring, waterborne Hg concentrations were reduced >80%; however, this did not translate into a comparable decrease in Hg bioaccumulation at most sites. Mercury bioaccumulation in fish did respond to decreased inputs in the industrialized headwater reach, but paradoxically increased in the lowermost reach of EFPC. As a result, the downstream pattern of Hg concentration in fish changed from one resembling dilution of a headwater point source in the 1980s to a uniform distribution in the 2000s. The reason for this remains unknown, but is hypothesized to involve changes in the chemical form and reactivity of waterborne Hg associated with the removal of residual chlorine and the addition of suspended particulates to the streamflow. PCB concentrations in fish varied greatly from year-to-year, but always exhibited a pronounced downstream decrease, and appeared to respond to management practices that limited episodic inputs from legacy sources within the facility.