bluuebunny/crossref_metadata_2025 huggingface dataset:
Final Disposal Demonstration Programmes
Authors: Govaerts Paul
Published: April 2020

THE ECONOMIC INTEREST GROUPING EURIDICE: In 1995, SCK•CEN (the Belgian research centre for nuclear energy) and NIRAS/ONDRAF (National agency for radioactive waste and enriched fissile materials) founded the Economic Interest Grouping (EIG) PRACLAY in order to develop and facilitate their economic activities. The most important objective of the EIG PRACLAY is the realisation of the PRACLAY project, aiming a demonstration of the technical feasibility of the disposal of heat generating radioactive waste in the Boom clay.
Final Disposal Through Public Participation
Authors: Van Negen P.
Published: April 2020

The Context:

• 1998. The Belgian government selects the existing nuclear sites for the long term disposal of Class A nuclear waste.

• ONDRAF/NIRAS, the Belgian Agency for Radioactive Waste and enriched Fissile Materials, adopts an innovative approach of active participation and sysematic dialogue with the local communities.
HUP Immobilization of Uranium and Plutonium From Surrogate Liquid Radioactive Solutions Using Porous Molded Glass Crystalline Blocks (Gubka)
Authors: Aloy A. S. , Sapozhnikova N. V. , Anshits A. G. , Sharonova O. M. , Tretyakov A. A. , Knecht D. A. , Tranter T. J. , Macheret J.
Published: April 2020

This paper describes test results for immobilization of surrogate radioactive actinide solutions. A glass crystalline porous material, Gubka, or “sponge” in Russian, was tested to immobilize surrogates of two types of actinide solutions, which exist in the DOE complex. Solutions using uranium as a surrogate for plutonium were stabilized in the porous Gubka block by successive saturation and drying cycles. After calcining, fully dense glass-ceramic tablets were formed in a hot uniaxial press. The tablets included 2–3 different glass phases with no uranium content and a uranium phase. Detailed electron micrographs and X-ray diffraction results are presented in the paper.
New or Modified Old Conceptual Approach to HLLLW Management
Authors: Ninkovic Marko M. , Raicevic Jagos J.
Published: April 2020

One of the greatest challenges in the use of nuclear energy is the high radioactive long-lived waste which is generated during production. It must be dealt with safely and effectively. While technical solutions exist, including deep geological repositories, progress in the disposal of radioactive waste has been influenced, and in many cases delayed, by public perceptions about the safety of the technology. One of the primary reasons for this is the long life of many of radionuclides, actinides and fission products, with half-lives on the order of a hundred thousand to a million years. Problems of perceptions could be reduced significantly, according to our and many others author’s opinion, if there were a way to burn or destroy the most toxic long-lived radioactive wastes. As there are no industrial methods for waste destroying today, in this paper it was suggested a new hybrid approach: instead of final waste disposal, long-termed but yet temporal storage only, striving towards final destruction once a appropriate conditions are maintained. This new or modified old approach could affect current HLLLW management and related activities in: changes of processing technology; prolonging the time period of waste storage at temporal depositories; increasing the investment into research regarding the methods and technologies for destructions of these materials, and slowing down the investments into the very expensive final disposal repositories. It’s authors opinion that such conceptual approach would contribute the reviving interest in nuclear energy, all over the world and especially in small and developing countries.
Recent Developments in D&D of Nuclear Facilities in Spain
Authors: Santiago Juan L. , Vidaechea Sergio
Published: April 2020

Spain occupies a leading position at international level in the field of installation decommissioning. Decommissioning projects have already been performed in relation to uranium mills, the rehabilitation of disused uranium mines is currently in the final phase and the dismantling of the Vandellós-I Nuclear Power Plant is now under way.

On the basis of this experience, this paper describes the key issues in decommissioning technology and presents the approaches adopted by ENRESA to tackle the decommissioning strategy in Spain. In particular practical dismantling and decontamination methods are described, and material and radioactive waste management are discussed.
Superphénix LMFR Decommissioning Sodium Retention Treatment by Mechanical Drilling of Internal Structures
Authors: Baque F. , Haudiquet C. , Major P.
Published: April 2020

For the decommissioning of the French 1200 MWe Liquid Metal Fast Reactor SUPERPHENIX, twenty-five processes were selected to pierce liquid sodium trapping zones after draining of the main vessel. Four processes were chosen and closely studied: mechanical drilling, laser shooting, high pressure liquid cutting, replacement of liquid sodium by another heavier liquid.

Mechanical drilling was finally selected: some in-air tests at room temperature were performed with conventional machines, then some in-sodium tests at 180°C, using a prototype machine. The drilling conditions and tools, the chip recovering sequence and the efficiency of the scenario (four successive drilling operations in three piled plates) were validated: the liquid sodium was drained off.
Decommissioning the Georgia Tech Research Reactor
Authors: Eby Robert , Lundberg Lark , Marske Steve , Hertel Nolan , Ice Rod
Published: April 2020

The Georgia Tech Research Reactor (GTRR) is a 5-megawatt (MW) heavy-water-cooled nuclear reactor located on the Georgia Institute of Technology (Georgia Tech) campus in downtown Atlanta, Georgia. On July 1, 1997, Georgia Tech administration notified the U.S. Nuclear Regulatory Commission (NRC) of their intent to decommission the GTRR. In the summer of 1999, the NRC issued a license amendment to decommission the GTRR in accordance with NRC’s Regulatory Guide 1.86. In the spring of 1999, Georgia Tech and the State of Georgia contracted CH2M HILL to serve as the Executive Engineer to manage the decommissioning project. Later in the summer of 1999, the IT Corporation was selected as the Decommissioning Contractor. The Decommissioning Contractor began the dismantlement process at the Georgia Tech site in November, 1999. By February, 2000, reactor support systems such as the primary and secondary cooling water systems, and the bismuth cooling system were removed and packaged for off-site disposal. Reactor internals were removed in April, 2000. Removal of the bioshield occurred from May through November, 2000. Throughout January, 2001, various concrete structures, including the Spent Fuel Storage Hole, were decontaminated. Dismantlement and decontamination activities were completed by April, 2001. The Final Survey Report to the NRC is planned to be submitted to the NRC December, 2001, 2001. Final license termination by the NRC is anticipated in the spring of 2002.
The Decontamination and Decommissioning of a 2 000 m3 Open Storage Pond for Liquid Waste and Sludges
Authors: Walthéry Robert , Teunckens Lucien , Lewandowski Patrick , Millen Danny , Baumann Sven
Published: April 2020

In the beginning of April, 1998, Belgoprocess started the large scale decommissioning of shutdown facilities at the former waste treatment department of the Belgian Nuclear Research Centre (SCK•CEN).

In the second half of 2000, the decommissioning of a former open concrete storage pond was started. It has two parts, one with a volume of 200 m3, the other has a volume of 2 000 m3. In the past, the tanks were used as open cooling reservoir for the scrubber water of an incinerator for low level beta-gamma wastes. As a result, it contained some 126 Mg of sludges that were treated in a bituminisation facility.

After emptying and rinsing of the tanks, samples were taken from the inner (brick) and the outer (concrete) wall to define the contamination levels in the material. It was found that the first layer of about one centimetre of the brick wall showed some radium contamination. Samples taken from the outer wall showed no contamination, which does not mean that the entire outer wall should be free of contamination. It was seen that the outer wall had some cracks, and there was no guarantee that a layer of bitumen in between the two walls was still in good condition. Also the top layer of the concrete bottom proved to be radium contaminated.

The outer walls of the storage pond were supported by a thick layer of soil, which proved to contain some spots of contamination. The contaminated soil was segregated and evacuated, the remaining part was removed to a temporary storage area, waiting to be monitored for final unconditional release.

The paper gives an overview of the decommissioning activities relating to the open concrete storage pond at the former waste treatment department of the Belgian Nuclear Research Centre (SCK•CEN).
ATENA: Project of Storage and Disposal Plant for Radioactive Sodium Wastes
Authors: Rodriguez G. , Thomine G. , Serpantié JP. , Demoisy Y.
Published: April 2020

CEA, in the framework of its research and development activities in support of Liquid Metal Fast Reactors (LMFR), has developed experimental or demonstration plants, now at end of life, which are potential or existing sources of wastes containing sodium.

The sodium waste management of CEA forecasts the disposal of the sodium contained in these wastes by water and soda processes, with existing means for the non radioactive sodium, and with a specific plant, to be built, for radioactive sodium.

The project ATENA (Atelier de Traitement et d’Entreposage du Na Actif, Workshop for Processing and Storage of radioactive Na) answers to this need of central processing plant for radioactive sodium wastes generated by CEA.

It concerns only the wastes:

• containing radioactive sodium,

• transportable,

• which could not be processed by Phénix and Superphénix facilities for treatment of large primary or secondary sodium volumes, presently in project.

FRAMATOME ANP direction NOVATOME, French LMFR engineering, is chosen as project manager for ATENA.

ATENA will be a new plant with:

• a storage module, able to be a central storage for wastes held at present by several of CEA’s plants,

• a process module: disposal of sodium with several processes,

• a packaging module for wastes resulting from these treatments: packaging of soda and metallic pieces in solid ultimate wastes.

The three chosen disposal processes are existing and are validated. They apply to several wastes to be processed according to the activity of the contained sodium, to the capability of the sodium to be liquified or separated from its container:

• continuous and controlled injection of liquid sodium in soda (NOAH process),

• treatment of solid sodium aggregated with metallic pieces, by controlled and continuous spray of water (Enceinte de Lavage en Actif, Active Washing Enclosure),

• treatment of solid and very radioactive sodium, aggregated or not with metallic pieces, by non-controlled immersion in water (Autoclave).

We present the general concepts of ATENA plant, the process options and safety principles as chosen after the basic design phase.
Management of Mixed Hazardous and Radioactive Waste in the United States
Authors: Greenman William , Cole Kimberly
Published: April 2020

In the United States, mixed-waste is typically defined as waste that contains both radioactive constituents and non-radioactive constituents that pose a threat to human health or the environment (hazardous waste). Prior to 1986 the U.S. Nuclear Regulatory Commission (NRC) had sole regulatory authority over mixed-waste because of its radioactive constituents. In 1986, however, the U.S. Environmental Protections Agency (EPA) was granted regulatory authority over the hazardous constituents in mixed-waste; and, a system of dual regulation was created. Dual regulation of mixed-waste by the EPA and the NRC has caused significant problems for the regulated community. The burden of dual regulation has contributed to the slow development of treatment technologies, and to the overall lack of treatment capacity available to U.S generators of mixed-waste. This paper reviews the requirements that the EPA and the NRC mandate with regard to mixed-waste generation, treatment and disposal; and it explores technical impacts of those requirements as they relate to generators, treatment facilities and the public.
Some Results From Geotechnical Research on Bentonite
Authors: Pacovsky Jaroslav , Travnicek Radek , Vasicek Radek
Published: April 2020

A solution of safe isolation of radioactive waste represents a multidisciplinary problem. The waste isolation is to be provided by a multi-barrier system of an underground repository based on a system of several barriers. The system will consist of a container with high level radioactive wastes itself, an engineering barrier — currently intended to be based on ‘bentonites’ — and natural barrier formed with a suitable rock environment. Each of those barriers alone should prevent spreading of hazardous radionuclides from the container to the biosphere.

In its main part, this paper deals with laboratory research of some most important geotechnical requirements for the engineering barrier, assumedly based on bentonites materials. The group of tested properties contains:

• Hydrophysical properties - permeability, swelling ability, Atterberg’s consistency limits

• Physico-technical properties - thermal properties

• Rheology

Creation of mathematical and physical models forms an independent part of the complex research project for materials of the geotechnical part of the engineering barrier. In the conclusion a short consideration on a prepared physical model of container has been made.
Experimental Research of 14C Migration in Loess and Clay: Distribution Coefficients and Retardation Factors
Authors: Arsene Carmen , Negoiu Dumitru , Andrei Veronica
Published: April 2020

One of the priorities of Romanian program for radioactive waste management is the establishing of the emplacement medium of the low and intermediate radioactive waste repository.

Since 1994, the Saligny site, the potential location for low and intermediate repository in Romania, has been under physical, chemical, hydrological, mineralogical and radionuclide migration investigations.

The understanding and quantification of radionuclide transport in the geological medium is of primary importance with respect to safety and environmental impact assessment for prospective waste management site.

Because of its radiochemical characteristics, 14C, contained in low and medium radioactive wastes generated from operation of Cernavoda NPP Unit 1, require a special attention as concerns their disposal.

Laboratory experiments were conducted to determine the transport parameters of 14C that characterise its migration in the geological formations of the Saligny site.
Special Waste Generated by the Belgian Nuclear Research Centre
Authors: Van Alsenoy Veerle , Demeulemeester Yves , Noynaert Luc , Klein Michel , Lardot Nicolas
Published: April 2020

At research centres, test programs generate very particular waste forms, which cannot be treated using the known regular scenario’s and procedures, and therefore special studies need to evaluate safe handling of these special waste forms. This paper describes how a joint effort between the Belgian Agency for Radioactive Waste and Enriched Fissile Materials, the Belgian Waste Treatment and Storage Facility Belgoprocess, and the Belgian Nuclear Research Centre worked out solutions for the 1st beryllium moderator of the BR2 and the highly activated internal parts of the BR3. The current position regarding activated graphite and aluminium is also summarised.
The Safety Case for a Deep Geological Repository: More Than Just Presenting Numbers
Authors: Schneider Jürg W. , Johnson Lawrence H. , Zuidema Piet , Smith Paul A. , Gribi Peter
Published: April 2020

A convincing safety case is a prerequisite for positive decisions in the stepwise process of planning and implementing a deep geological repository. In addition to evaluations of dose or risk, a safety case must provide arguments that the system and its safety functions are well understood, that the methods, models and data used in the evaluations are applicable, and have been correctly applied, and that the full spectrum of possibilities for the characteristics of the repository system and its evolution has been taken into account in defining the cases to be evaluated. This paper takes examples from the Swiss waste management programme and from natural analogue studies to illustrate how the safety functions for a repository are taken into account in a safety assessment and how independent evidence can be used to support the statement that these safety functions will operate as expected.
Lessons Learned at the Waste Isolation Pilot Plant: Share, Listen, and Learn to Earn Stakeholder Acceptance
Authors: Eriksson Leif G.
Published: April 2020

On March 26, 1999, the United States (U.S.) Department of Energy (DOE) opened the nation’s first deep geological disposal system (repository) for long-lived radioactive wastes/materials (LLRMs) at the Waste Isolation Pilot Plant (WIPP) site, New Mexico, United States of America (USA). The opening of WIPP embodies gradually achieved acceptance, both local and global, on scientific, institutional, regulatory, political, and public levels. In the opinion of the author, five significant determinants for the successful siting, certification, and acceptance of WIPP, were the existence of:

• A willing and supportive host community;

• A strong, independent regulator;

• A regulatory framework widely perceived to (over)protect public health and the environment;

• A structurally simple, old, stable, host-rock with excellent radionuclide containment and isolation characteristics; and

• An open siting, site characterization, repository development, certification and recertification process with regularly scheduled opportunities for information exchanges with affected and interested parties, including a) prompt responses to non-DOE concerns and b) transparency/traceability of external-input into, and the logic behind, the DOE’s decision-making process.

The nation’s and the world’s next deep geological repository for LLRMs is currently scheduled to open in 2010. As follows, in addition to providing a national solution to safe disposal of LLRMs, the opening and continued safe operation of WIPP provides an international role model that effectively dispels the global myth that LLRMs cannot be safely disposed in a deep geological repository.
Mitigation of Uranium in Effluents by Zero Valent Iron: The Role of Iron Corrosion Products
Authors: Noubactep Chicgoua , Volke Peter , Merkel Broder , Meinrath Günther
Published: April 2020

This study was conducted to investigate the influence of iron corrosion products on the removal precipitation of uranium (VI) from aqueous solutions by zero valent iron (ZVI). Batch experiments were conducted with solutions containing 20 mg /L U(VI) (0.084 mM) at room temperature with washed and untreated scrap iron.

The results show significant decrease of the immobilization efficiency of ZVI for uranium in the presence of both atmospheric corrosion products and those generated in situ. Among the relevant groundwater components, those who promote the iron corrosion e.g. SO42−, Cl− produce more corrosion products and have a stronger negative effect on the immobilization process. Carbonate ions also have a negative effect on the immobilization efficiency since they form stable complexes with uranium and reduce the adsorption on the iron surface which is the first step to immobilization. Humic substances didn’t show any negative effect but rather a slight enhancement of the immobilization rate. These results show that washing ZVI materials with hydrochloric acid before testing will overestimate their efficiency in practical use.
Stabilisation of Soft Tailings: Practice and Experience
Authors: Jakubick Alex T. , McKenna Gord
Published: April 2020

Environmentally acceptable reclamation solutions for the decommissioned tailings ponds can be achieved by integrating the tailings deposits into the landscape either by turning the tailings pond/deposit into a lake and maintaining a permanent water cover over the deposit or by stabilisation of the deposits as a “dry” landform.

Conceptually, the dry landscape reclamation involves three remedial steps: 1) Placement of an interim cover on the tailings surface to provide the consolidation load and create a stable working platform. 2) Building of a surface contour providing suitable run off conditions for the surface water. 3) Capping the surface with a final cover to control infiltration into the tailings.

For reliable predictions of consolidation, proper sequencing of remedial steps/measures and cost efficient reclamation of soft tailings it is necessary to use Non Linear Finite Strain (NLFS) codes. The advantage of the NLFS program system Consol2D is that it allows the reconstruction of the history of the tailings discharge, the evaluation of the material parameters, the calculation of settlement in inhomogeneous deposits, the 3D quantification of the settlement trough and the evaluation of the drainage effect of the vertical drains.
NDA in the Frame of Waste Characterization and the Practice at Belgoprocess
Authors: Botte John , Hendrickx Jean-Paul , Luycx Paul
Published: April 2020

Governments and the nuclear sector realize more and more the importance of waste characterization in the end cycle.

Several methods are available for radiological characterization. Each method has his advantages and disadvantages in regard to the definition of the operational range based on the waste characteristics and the knowledge of the waste.

The decision on what technique(s) to be used will be based on the required precision, accuracy, detection limit and isotopes to be declared for a certain purpose and on the related costs.

Recently Belgoprocess, the Belgian waste treatment facility, has performed large efforts and investments to assure a good waste characterization.
Fabrication of MOX Storage Rods for Direct Final Disposal As Method for Immobilisation of Surplus Plutonium
Authors: Küppers Christian , Sailer Michael
Published: April 2020

The German strategy of handling spent fuel was focussed on reprocessing since the 1960s although the German breeder projects are phased out since the late 1980s. Therefore, considerable plutonium was separated from German spent fuel and not reused. Some materials are not storable without periodical treatment and must be processed. The question arises whether a product can be fabricated that is also suitable for final disposal. Fabrication of “MOX storage rods” is considered to be the best treatment, especially under German conditions, for this purpose. This treatment can also reduce costs significantly, probably up to one third. The storage rod option is based on techniques of which Europe has large-scale technical experience and only existing facilities are needed. Relevant amounts of plutonium could be processed in a relatively short time, this means several tons per year, starting before 2005.
Development of Cutting Techniques Applied on Sodium Wastes Application to Liquid Metal Fast Reactors (LMFRS) Decommissioning
Authors: Rodriguez G. , Goedert N. , Cournille M.
Published: April 2020

In the frame of the general clearing of CEA centres of sodium waste, a new Based Nuclear Installation (BNI) is being studied to collect all the active sodium wastes and to treat them in the same building. This BNI is called ATENA. (Atelier de Traitement et Entreposage des déchets Na)

In designing ATENA, CEA identified that there was a lack in the knowledge of techniques for the cutting of metallic sodium wastes. Therefore it was decided to test several cutting technologies on different sodium wastes to evaluate their performances in a specific situation.

These experiments started with a general review of all the cutting techniques used for decommissioning purposes to see if they could be compatible with sodium safety standards.

Several cutting techniques were dismissed and finally eight cutting techniques were selected to be tested with sodium. Four of them were considered to be the best. This paper describes these sodium-cutting trials and explains the reasons of the final selection.
The Research in France on Disposal Concepts for High Level and Long Lived Radioactive Waste in Deep Clay Formation
Authors: Hoorelbeke Jean-Michel , Chupeau Joël , Loubrieu Jean , Poisson Jean-Baptiste , Poisson Richard
Published: April 2020

The 15 year research on high level and long lived radioactive waste disposal in deep geological formations is being carried out by the ANDRA within the framework of the 1991 law. The status of the research program corresponds to the sinking of the shafts of the Meuse/Haute-Marne Underground Research Laboratory in an argilite layer.

A set of preliminary concepts associated to this argillite layer has been studied to help address the issues raised by the feasibility analysis of a potential repository with respect to safety objectives. These concepts deal with transuranic no heat emitting waste, high level vitrified waste and potentially disposed spent fuel.

Provision is made for a high level of flexibility, in particular regarding the reversibility of the step by step disposal process.

The architecture of the repository concepts distinguishes disposal zones dedicated respectively to transuranic (type B) waste, vitrified high level (type C) waste, UOX and MOX spent fuel (if the case arrises). Each zone is itself divided into modules. The modular design, which segregates the waste categories, guarantees in particular the flexibility of the repository to contend with potential variations in inventory or waste management modes. This makes it possible to study the feasibility of disposal of each type of waste, in an independent way from the others.

For each disposal zone and waste category, current studies, including safety and cost analysis, enable to compare various design options of the disposal cells and modules, prior to selecting those which will be presented in 2005.

The paper mentions research targets of the program aiming at answering major scientific and technological questions raised by the concepts.

The next milestone of the research program is scheduled at the end of the year 2001. It aims at tuning the approach to be used to assess the feasibility of disposal by 2005.

The design will progressively benefit from the research carried out in the Meuse/Haute Marne underground research laboratory and other fields: The resulting data make it possible to fit the models used to dimension the structures, especially in the 2002–2005 period.
Waste Avoidance Program for Mercury-Laden Mixed Waste
Authors: Cournoyer Michael E. , Martinez Timothy P. , Grundemann Robert F.
Published: April 2020

Mercury is ideal for use in such things as thermometers and vacuum gauges (manometers) because this naturally occurring silvery liquid expands and contracts evenly with temperature and pressure changes. Within the Nuclear Materials Technology (NMT) Division of Los Alamos National Laboratory, mercury containing devices are used for a variety of operations, including actinide chemistry, weapons production, radiochemistry, and analytical chemistry. Mercury present in these instruments does not in itself constitute a risk of contamination since the metal is contained within a closed system. However, breakage, inadequate maintenance and disposal of such instruments can expose workers and the public to this toxic substance.

In this study, waste minimization issues associated with replacing these mercury-laden instruments with non- and less-hazardous devices are addressed. These include institutional program available to support this effort, the hazards grouped with mercury, and devices that use mercury. Life cycle management issues are also examined. Procedures and waste minimization processes used to remove the metallic mercury from an operation will be presented. A project in which mercury containing thermometers and manometers are systematically replace with less hazardous instruments is discussed. This project resulted in approximately 5 kilograms of mercury being removed from Radiological Controlled Areas during project, which represents the elimination of a potential liability of the generation of 100 m3 of Mixed Low-Level Waste in the future. As a final step, an approach to get buy-in from both technical and budget minded employees is presented. The elimination and substitution of hazardous materials in NMT Division is an ongoing process that starts during the design phase of a process or facility and continues through the performance of routine procedures.
Reduction of Radioactive Waste Production: Where Is the Optimum?
Authors: Havard P.
Published: April 2020

Low and medium level waste management means reducing the amount of waste generated during maintenance and operation of the plant, in accordance with the ALARA concept, while keeping not only the quality of the product but also the associated costs under control.

All this waste is managed by ONDRAF/NIRAS, the Belgian Federal Agency responsible for waste management, including conditioning, intermediate storage and final disposal.

Unfortunately, the actions taken by ONDRAF/NIRAS and the producers in order to reduce waste production have had a negative impact on waste treatment tariffs.

It has become necessary to re-examine the relationship between ONDRAF/NIRAS and the producers, in order to control the costs of waste management. This problem concerns not only the treatment costs but also the disposal costs.

The volume of waste has fallen from 30M3/Thwh in 1985 to 4.m3/Twh in 2000, not by chance but as the result of a new site organisation geared towards achieving this aim. This paper presents firstly the history of Belgian waste management, taking into account the impact on the associated costs, and secondly the measures that have to be taken in order to be able to decide which new technologies are necessary to go further with the objective of waste volume reduction in a new environment, namely deregulation and consequently high pressure on production costs. Finally, it presents a few conclusions.
The Decontamination of Lead Shielding Blocks for Unrestricted Re-Use or Re-Cycle
Authors: Ensor Brian , Calloway Michael , Chambers Trevor N. , Inns Alec J. , Partridge David J.
Published: April 2020

Since 1997, the United Kingdom Atomic Energy Authority (UKAEA) and NNC Ltd. have embarked on the decommissioning and demolition of a redundant metallurgical facility at Harwell. The metallurgical suite comprised three concrete-shielded remote handling cells and 36 lead-shielded enclosures, with associated support and electron microscopy facilities. The decommissioning work carried out by NNC entails the dismantling of the 36 lead enclosures, which were expected to yield over 1000 tonnes of lead shielding blocks as waste. The decommissioning project is nearing completion, with only two large enclosures remaining to dismantle. This paper describes the management and technical processes utilised in the treatment of the lead blocks, in order to re-use or re-cycle the lead materials as far as reasonably practicable.

In processing 700 tonnes of lead block arisings from the decommissioning of this facility so far, NNC and UKAEA have segregated over 400 tonnes of uncontaminated lead and decontaminated approximately 250 tonnes of lead for unrestricted re-use or for recycling, after smelting. Much of this material would otherwise have been consigned as low level radioactive waste. Secondary low level radioactive wastes arising from the decontamination process have amounted to approximately 15 m3 to date, of which only a small proportion of the arisings are lead shavings.
Radioactive Waste Treatment From Mo-99 Production Facility in the Netherlands
Authors: Van Kleef Rozé M. , Duijves Klaas A.
Published: April 2020

In Petten, the Netherlands, a Molybdenum Production Facility (MPF) has been realised since 1994 by the Nuclear Research and Consultancy Group (NRG) in close co-operation with Mallinckrodt, a company that produces isotopes for medical applications at the same site. The facility is operated by Mallinckrodt personnel under the license of NRG. At this moment the facility has a weekly production rate of 0,4 PBq (10,500 Ci). The management of the radioactive waste treatment, developed by Mallinckrodt, NRG and COVRA, has been one of the key issues during the development of the production facility.

COVRA is the Central Organisation for Radioactive Waste in the Netherlands and responsible for the execution of the radwaste policy of the Dutch government. For solid and liquid low level waste (LLW) the existing route at COVRA was available. For the handling of solid and liquid intermediate level waste (ILW) from the MPF, a new system for transport, interim storage and treatment had to be developed. Therefore the Mo-waste project was established in 1994.

This project included the following issues:

• development, construction and operation of a filling and packaging station for liquid waste at the production site,

• design, engineering, fabrication and testing of Type A-transport containers for both the solid and liquid ILW,

• modification of transport vehicle,

• design and realisation of interim storage and treatment facilities for both the solid and liquid ILW at the COVRA site.

At this moment the completed facilities have successfully undergone the hot testing phase. The experiences achieved confirmed the rightness of the choice to integrate the COVRA waste management concept in the Molybdenum production cycle.
CONSTOR® Transport and Storage Cask for Spent Fuel and for High Active Waste
Authors: Diersch Rudolf , Gartz Robert , Gluschke Konrad
Published: April 2020

The CONSTOR® was developed with special consideration to an economical and effective way of manufacturing by using conventional mechanical engineering technologies and common materials. The main objective of this development was to fabricate these casks in countries not having highly specialized industries for casting or forging of thick-walled casks. Nevertheless, the CONSTOR® concept fulfills both the internationally valid IAEA criteria for transportation and the German criteria for long-term intermediate storage. The basic cask concept has been designed for adaptation to different spent fuel specifications as well as handling conditions in the NPPs. Adaptations have been made for spent fuel from RBMK and VVER reactors, and also for BWR spent fuel and high active waste.

So far, 30 CONSTOR® RBMK-1500 original casks have been manufactured and delivered to Ignalina Nuclear Power Plant in Lithuania. Two of these have been succesfully loaded during hot trial tests and placed in storage.

The CONSTOR® cask for RBMK fuel has obtained the type B(U)F verification certificate from the Russian authority GAN and the release for manufacturing as a storage cask by the Lithuanian Authority VATESI. Following the successful hot trials, the final storage license from VATESI is expected in the near future. The type B(U)F licensing in the Czech Republic will be finished in 2001.
8 Years Working of ENTRAP’s Working Group on Non-Destructive Testing of Waste Packages
Authors: Bruggeman M. , Van Iseghem P. , Odoj R. , Lierse von Gostomski Ch. , Dierckx R.
Published: April 2020

ENTRAP is a European organisation grouping nuclear waste quality checking laboratories from different EU member states. The main objectives of ENTRAP are information exchange and harmonisation between the laboratories. ENTRAP works on different aspects of quality checking of nuclear waste packages. The working items are treated in different working groups and one of these working groups is WGA, dealing with non-destructive assay techniques for waste packages. This paper discusses the main achievements made by WGA, and gives a summary of the state-of-the-practice of assay techniques used for quality checking of nuclear waste packages in the different member laboratories.
Quality Assurance in Radwaste Conditioning, Long-Term Interim Storage and Disposal in Germany
Authors: Brennecke Peter , Giller Heinz , Steyer Stefan , Theis Stefan
Published: April 2020

A nationwide harmonized quality assurance system for radwaste conditioning, interim storage and final disposal has been implemented in Germany. Up to now the guideline for all steps have been the waste acceptance criteria for the final disposal facilities Morsleben and Konrad. While the first one is in the stage of preparation for final closure the startup of the latter will be postponed for at least another 10 years. Possibly the next German repository will not be located at Konrad and start operation as late as 2030. This change in disposal policy has significant impact on the conditioning and QA-procedures today.
Designing complex architectured materials with generative adversarial networks
Authors: Mao Yunwei , He Qi , Zhao Xuanhe
Published: April 2020

Complex architectured materials are designed with generative adversarial networks to approach Hashin-Shtrikman upper bounds.
Histidine Utilization Is a Critical Determinant of
Acinetobacter
Pathogenesis
Authors: Lonergan Zachery R. , Palmer Lauren D. , Skaar Eric P.
Published: April 2020

Acinetobacter baumannii
is a nosocomial pathogen capable of causing a range of diseases, including respiratory and urinary tract infections and bacteremia. Treatment options are limited due to the increasing rates of antibiotic resistance, underscoring the importance of identifying new targets for antimicrobial development. During infection,
A. baumannii
must acquire nutrients for replication and survival. These nutrients include carbon- and nitrogen-rich molecules that are needed for bacterial growth.
Using Student-Led Discussion and Reflection of a Public Health–Related Nonfiction Book as a Tool to Encourage Inclusive Pedagogy in an Undergraduate Classroom
Authors: Pandey Sumali , Wisenden Patricia , Shegrud Whitney R.
Published: April 2020

Educators realize the need to provide an inclusive, safe environment in a diverse classroom setting to encourage discussion of sensitive topics. However, descriptions of evidence-based approaches that may help us to meet inclusive pedagogy–related competencies are limited. Here, we describe a discussion format that followed chapter readings from a nonfiction biographical book called
Mountains beyond Mountains: The Quest of Dr. Paul Farmer, a Man Who Would Cure the World
(2003), by Tracy Kidder. This semester-long effort allowed sufficient time for students to develop an understanding of global public health affairs and to reflect on their own role in this world as responsible citizens. A discussion around several sensitive issues emerged, such as the extent of their belief in faith versus science, their opinion on providing financial aid to developing countries versus addressing public health issues in their home country, stereotypes and how that may spread panic during a public-health emergency. The student essays provided evidence that activities were successful in 1) drawing out students’ voices about world affairs, 2) teaching students to empathize with varied belief systems, 3) helping students develop a deeper appreciation of empirical and ethical factors that may affect such issues—all of which are key competencies for an inclusive classroom setting. We believe that the activities are flexible in structure and could be easily incorporated into a biology or liberal arts classroom setting to achieve inclusive pedagogy–related goals.
Supplemental material: Detrital zircon U-Pb geochronology and Hf isotope geochemistry of Paleozoic and Triassic passive margin strata of western North America
Authors: Gehrels George , Pecha Mark
Published: April 2020

Geosphere, February 2014, v. 10, p. 49-65, doi:10.1130/GES00889.1, Supplemental File 2 - CL image file (238 pages). File size is ~23 MB.
Supplemental material: The Confusion Range, west-central Utah: Fold-thrust deformation and a western Utah thrust belt in the Sevier hinterland
Authors: Greene David C.
Published: April 2020

Geosphere, February 2014, v. 10, p. 148-169, doi:10.1130/GES00972.1, Plate 2 - Cross section of the northern Confusion Range, A–A′.
Top 10 evidence-based countermeasures for night shift workers
Authors: Wallace Patrick J , Haber Jordana J
Published: April 2020

Emergency edicine providers are responsible for ensuring the emergency department is staffed 24 hours a day. As such, providers must efficiently transition between day, swing and night shift on an almost weekly basis. There is no formal education in medical school or residency on how to approach the transition to and from night shift, remain alert and productive and maximise sleep during the day. There are a multitude of blogs and online sources discussing night shift, but few, if any, provide an evidence-based approach. This article will provide the top 10 evidence-based recommendations to increase sleep, maximise performance, decrease fatigue on shift and improve quality of life outside the workplace.
Glossary for public health surveillance in the age of data science
Authors: Chiolero Arnaud , Buckeridge David
Published: April 2020

Public health surveillance is the ongoing systematic collection, analysis and interpretation of data, closely integrated with the timely dissemination of the resulting information to those responsible for preventing and controlling disease and injury. With the rapid development of data science, encompassing big data and artificial intelligence, and with the exponential growth of accessible and highly heterogeneous health-related data, from healthcare providers to user-generated online content, the field of surveillance and health monitoring is changing rapidly. It is, therefore, the right time for a short glossary of key terms in public health surveillance, with an emphasis on new data-science developments in the field.
Intergenerational transmission of alcohol misuse: mediation and interaction by school performance in a Swedish birth cohort
Authors: Almquist Ylva B , Bishop Lauren , Gustafsson Nina-Katri , Berg Lisa
Published: April 2020

Background

Children whose parents misuse alcohol have increased risks of own alcohol misuse in adulthood. Though most attain lower school marks, some still perform well in school, which could be an indicator of resilience with protective potential against negative health outcomes. Accordingly, the aim of this study was to examine the processes of mediation and interaction by school performance regarding the intergenerational transmission of alcohol misuse.

Methods

Data were drawn from a prospective Swedish cohort study of children born in 1953 (n=14 608). Associations between parental alcohol misuse (ages 0–19) and participants’ own alcohol misuse in adulthood (ages 20–63) were examined by means of Cox regression analysis. Four-way decomposition was used to explore mediation and interaction by school performance in grade 6 (age 13), grade 9 (age 16) and grade 12 (age 19).

Results

Mediation and/or interaction by school performance accounted for a substantial proportion of the association between parental alcohol misuse and own alcohol misuse in adulthood (58% for performance in grade 6, 27% for grade 9 and 30% for grade 12). Moreover, interaction effects appeared to be more important for the outcome than mediation.

Conclusion

Above-average school performance among children whose parents misused alcohol seems to reflect processes of resilience with the potential to break the intergenerational transmission of alcohol misuse. Four-way decomposition offers a viable approach to disentangle processes of interaction from mediation, representing a promising avenue for future longitudinal research.
Balancing the duty to treat with the duty to family in the context of the COVID-19 pandemic
Authors: McConnell Doug
Published: April 2020

Healthcare systems around the world are struggling to maintain a sufficient workforce to provide adequate care during the COVID-19 pandemic. Staffing problems have been exacerbated by healthcare workers (HCWs) refusing to work out of concern for their families. I sketch a deontological framework for assessing when it is morally permissible for HCWs to abstain from work to protect their families from infection and when it is a dereliction of duty to patients. I argue that it is morally permissible for HCWs to abstain from work when their duty to treat is outweighed by the combined risks and burdens of that work. For HCWs who live with their families, the obligation to protect one’s family from infection contributes significantly to those burdens. There are, however, a range of complicating factors including the strength of duty to treat which varies according to the HCW’s role, the vulnerability of family members to the disease, the willingness of family members to risk infection and the resources available to the HCW to protect their family. In many cases, HCWs in ‘frontline’ roles with a weak duty to treat and families at home will be morally permitted to abstain from work given the risks posed by COVID-19; therefore, society should provide additional incentives to maintain sufficient staff in these roles.
Effects of dietary silicate levels on growth performance, nutrient digestibility, fecal microflora, odorous gas emissions, blood characteristics, and foot and mouth disease antibodies in weaning to finishing pigs
Authors: Lee Ji Hwan , Yun Won , Oh Han Jin , An Ji Seon , Kim Young Gwang , Lee Chang Gyu , Cho Jin Ho
Published: April 2020

The goal of this study was to investigate effects of different levels of silicate supplementation in weaning to finishing pigs. A total of 96 piglets [(Landrace × Yorkshire) × Duroc] with initial body weight of 11.30 ± 0.02 kg were used for 16 wk (six replicate pens with four pigs per pen). Dietary treatment consisted of 0% (CON), 0.1% (T1), 0.5% (T2), and 1.0% (T3) silicate in the basal diet. Inclusion of 0.1% dietary silicate increased (P < 0.05) body weight, average daily gain, and gain-to-feed ratio in 0–16 wk. In addition, inclusion of 0.1% dietary silicate increased (P < 0.05) crude protein digestibility in 8 and 16 wk, whereas it decreased (P < 0.05) Escherichia coli count and ammonia emissions throughout the study period. Additionally, inclusion of dietary silicate increased (linear, P < 0.05) white blood cell in 4 wk, whereas it increased (quadratic, P < 0.05) white blood cell counts in 8 and 16 wk. Blood urea nitrogen decreased (quadratic, P < 0.05), and lymphocyte and foot and mouth antibodies increased (quadratic, P < 0.05) when silicate level increased. In conclusion, supplementation of 0.1% silicate in the diet showed positive effects in weaning to finishing pigs.