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At least 1,045 records · Page 58

INDUSTRIAL CONTROL SYSTEM CYBER SECURITY: QUESTIONS AND ANSWERS RELEVANT TO NUCLEAR FACILITIES, SAFEGUARDS AND SECURITY

Typical questions surrounding industrial control system (ICS) cyber security always lead back to: What could a cyber attack do to my system(s) and; how much should I worry about it? These two leading questions represent only a fraction of questions asked when discussing cyber security as it applies to any program, company, business, or organization. The intent of this paper is to open a dialog of important pertinent questions and answers that managers of nuclear facilities engaged in nuclear facility security and safeguards should examine, i.e., what questions should be asked; and how do the answers affect an organization's ability to effectively safeguard and secure nuclear material. When a cyber intrusion is reported, what does that mean? Can an intrusion be detected or go un-noticed? Are nuclear security or safeguards systems potentially vulnerable? What about the digital systems employed in process monitoring, and international safeguards? Organizations expend considerable efforts to ensure that their facilities can maintain continuity of operations against physical threats. However, cyber threats particularly on ICSs may not be well known or understood, and often do not receive adequate attention. With the disclosure of the Stuxnet virus that has recently attacked nuclear infrastructure, many organizations have recognized the need for an urgent interest in cyber attacks and defenses against them. Several questions arise including discussions about the insider threat, adequate cyber protections, program readiness, encryption, and many more. These questions, among others, are discussed so as to raise the awareness and shed light on ways to protect nuclear facilities and materials against such attacks.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Advanced Test Reactor National Scientific User Facility Progress

The Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) is one of the world’s premier test reactors for studying the effects of intense neutron radiation on reactor materials and fuels. The ATR began operation in 1967, and has operated continuously since then, averaging approximately 250 operating days per year. The combination of high flux, large test volumes, and multiple experiment configuration options provide unique testing opportunities for nuclear fuels and material researchers. The ATR is a pressurized, light-water moderated and cooled, beryllium-reflected highly-enriched uranium fueled, reactor with a maximum operating power of 250 MWth. The ATR peak thermal flux can reach 1.0 x1015 n/cm2-sec, and the core configuration creates five main reactor power lobes (regions) that can be operated at different powers during the same operating cycle. In addition to these nine flux traps there are 68 irradiation positions in the reactor core reflector tank. The test positions range from 0.5” to 5.0” in diameter and are all 48” in length, the active length of the fuel. The INL also has several hot cells and other laboratories in which irradiated material can be examined to study material radiation effects. In 2007 the US Department of Energy (DOE) designated the ATR as a National Scientific User Facility (NSUF) to facilitate greater access to the ATR and the associated INL laboratories for material testing research by a broader user community. Goals of the ATR NSUF are to define the cutting edge of nuclear technology research in high temperature and radiation environments, contribute to improved industry performance of current and future light water reactors, and stimulate cooperative research between user groups conducting basic and applied research. The ATR NSUF has developed partnerships with other universities and national laboratories to enable ATR NSUF researchers to perform research at these other facilities, when the research objectives cannot be met using the INL facilities. The ATR NSUF program includes a robust education program enabling students to participate in their research at INL and the partner facilities, attend the ATR NSUF annual User Week, and compete for prizes at sponsored conferences. Development of additional research capabilities is also a key component of the ATR NSUF Program; researchers are encouraged to propose research projects leading to these enhanced capabilities. Some ATR irradiation experiment projects irradiate more specimens than are tested, resulting in irradiated materials available for post irradiation examination by other researchers. These “extra” specimens comprise the ATR NSUF Sample Library. This presentation will highlight the ATR NSUF Sample Library and the process open to researchers who want to access these materials and how to propose research projects using them. This presentation will provide the current status of all the ATR NSUF Program elements. Many of these were not envisioned in 2007, when DOE established the ATR NSUF.

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Annual Summary Report for the Remote-Handled Low-Level Waste Disposal Facility—FY 2020

This Fiscal Year (FY) 2020 annual summary report documents the continued adequacy of the performance assessment (PA), the composite analysis (CA) and associated operating disposal-authorization statement (ODAS) technical basis documents for the Remote Handled (RH) Low-Level Waste (LLW) Disposal Facility at Idaho National Laboratory. Annual review of the adequacy of the PA and CA for the RHLLW Disposal Facility ensures that conclusions of the analyses remain valid in accordance with requirements of Department of Energy (DOE) Order 435.1 Change 1, “Radioactive Waste Management.” In FY 2020, no significant operational changes or other activities occurred that would cause deviation from the assumptions in the PA and CA pertaining to disposal geometry, verification of waste characteristics, tracking disposal inventories against total limits, facility closure design, or institutional controls. Fifteen total waste-canister shipments were received at the RHLLW Disposal Facility, and 15 total waste canisters were emplaced.

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Effect of steam generator configuration in a loss of the RHR during mid-loop operation at PKL facility

The loss of the residual heat removal system in mid-loop conditions may occur with a non-negligible contribution to the plant risk, so the analysis of the accidental sequences and the actions to mitigate the accident are of great interest in shutdown conditions. In order to plan the appropriate measures to mitigate the accident is necessary to understand the thermal-hydraulic processes following the loss of the residual heat removal system during shutdown. Thus, transients of this kind have been simulated using best-estimate codes in different integral test facilities and compared with experimental data obtained in different facilities. In PKL (Primaerkreislauf-Versuchsanlage, primary coolant loop test facility) test facility different series of experiments have been undertaken to analyze the plant response in shutdown. In this context, the E3 and F2 series consist of analyzing the loss of the residual heat removal system with a reduced inventory in the primary system. In particular, the experiments were developed to investigate the influence of the steam generators secondary side configuration on the plant response, what involves the consideration of different number of steam generators filled with water and ready for activation, on the heat transfer mechanisms inside the steam generators U-tubes. This work presents the results of such experiments calculated using, RELAP5/Mod 3.3. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Design of the Long-term Waste Management Facility for Historic LLRW Port Hope Project - 13322

The Municipality of Port Hope is located on the northern shores of Lake Ontario approximately 100 km east of Toronto, Ontario, Canada. Starting in the 1930's, radium and later uranium processing by Eldorado Gold Mines Limited (subsequently Eldorado Nuclear Limited) (Eldorado) at their refinery in Port Hope resulted in the generation of process residues and wastes that were disposed of indiscriminately throughout the Municipality until about the mid-1950's. These process residues contained radium (Ra- 226), uranium, arsenic and other contaminants. Between 1944 and 1988, Eldorado was a Federal Crown Corporation, and as such, the Canadian Federal Government has assumed responsibility for the clean-up and long-term management of the historic waste produced by Eldorado during this period. The Port Hope Project involves the construction and development of a new long-term waste management facility (LTWMF), and the remediation and transfer of the historic wastes located within the Municipality of Port Hope to the new LTWMF. The new LTWMF will consist of an engineered above-ground containment mound designed to contain and isolate the wastes from the surrounding environment for the next several hundred years. The design of the engineered containment mound consists of a primary and secondary composite base liner system and composite final cover system, made up of both natural materials (e.g., compacted clay, granular materials) and synthetic materials (e.g., geo-synthetic clay liner, geo-membrane, geo-textiles). The engineered containment mound will cover an area of approximately 13 hectares and will contain the estimated 1.2 million cubic metres of waste that will be generated from the remedial activities within Port Hope. The LTWMF will also include infrastructure and support facilities such as access roads, administrative offices, laboratory, equipment and personnel decontamination facilities, waste water treatment plant and other ancillary facilities. Preliminary construction activities for the Port Hope LTWMF commenced in 2012 and are scheduled to continue over the next few years. The first cell of the engineered containment mound is scheduled to be constructed in 2015 with waste placement into the Port Hope LTWMF anticipated over the following seven year period. (authors)

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Linking RESRAD-OFFSITE and HYDROGEOCHEM Model for Performance Assessment of Low-Level Radioactive Waste Disposal Facility - 13429

Performance assessments are crucial steps for the long-term radiological safety requirements of low-level waste (LLW) disposal facility. How much concentration of radionuclides released from the near-field to biosphere and what radiation exposure levels of an individual can influence on the satisfactory performance of the LLW disposal facility and safety disposal environment. Performance assessment methodology for the radioactive waste disposal consists of the reactive transport modeling of safety-concerned radionuclides released from the near-field to the far-field, and the potential exposure pathways and the movements of radionuclides through the geosphere, biosphere and man of which the accompanying dose. Therefore, the integration of hydrogeochemical transport model and dose assessment code, HYDROGEOCHEM code and RESRAD family of codes is imperative. The RESRAD family of codes such as RESRAD-OFFSITE computer code can evaluate the radiological dose and excess cancer risk to an individual who is exposed while located within or outside the area of initial (primary) contamination. The HYDROGEOCHEM is a 3-D numerical model of fluid flow, thermal, hydrologic transport, and biogeochemical kinetic and equilibrium reactions in saturated and unsaturated media. The HYDROGEOCHEM model can also simulate the crucial geochemical mechanism, such as the effect of redox processes on the adsorption/desorption, hydrogeochemical influences on concrete degradation, adsorption/desorption of radionuclides (i.e., surface complexation model) between solid and liquid phase in geochemically dynamic environments. To investigate the safety assessment of LLW disposal facility, linking RESRAD-OFFSITE and HYDROGEOCHEM model can provide detailed tools of confidence in the protectiveness of the human health and environmental impact for safety assessment of LLW disposal facility. (authors)

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Progress of the High Level Waste Program at the Defense Waste Processing Facility - 13178

The Defense Waste Processing Facility at the Savannah River Site treats and immobilizes High Level Waste into a durable borosilicate glass for safe, permanent storage. The High Level Waste program significantly reduces environmental risks associated with the storage of radioactive waste from legacy efforts to separate fissionable nuclear material from irradiated targets and fuels. In an effort to support the disposition of radioactive waste and accelerate tank closure at the Savannah River Site, the Defense Waste Processing Facility recently implemented facility and flowsheet modifications to improve production by 25%. These improvements, while low in cost, translated to record facility production in fiscal years 2011 and 2012. In addition, significant progress has been accomplished on longer term projects aimed at simplifying and expanding the flexibility of the existing flowsheet in order to accommodate future processing needs and goals. (authors)

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Design, Development and Operational Experience of Demonstration Facility for Cs-137 Source Pencil Production at Trombay - 13283

Radioactive waste management is a vital aspect of any nuclear program. The commercial feasibility of the nuclear program largely depends on the efficiency of the waste management techniques. One of such techniques is the separation of high yield radio-nuclides from the waste and making it suitable for medical and industrial applications. This will give societal benefit in addition to revenue generation. Co-60, the isotope presently being used for medical applications, needs frequent replacement because of its short half life. Cs-137, the major constituent of the nuclear waste, is a suitable substitute for Co-60 as a radioactive source because of its longer half life (28 years). Indian nuclear waste management program has given special emphasis on utilization of Cs-137 for such applications. In view of this a demonstration facility has been designed for vitrification of Cs-137 in borosilicate glass, cast in stainless steel pencils, to be used as source pencils of 300 Ci strength for blood irradiation. An induction heated metallic melter of suitable capacity has been custom designed for the application and employed for the Cs-137 pencil fabrication facility. This article describes various systems, design features, experiments and resulting modifications, observations and remote handling features necessary for the actual operation of such facility. The layout of the facility has been planned in such a way that the same can be adopted in a hot cell for commercial production of source pencils. (authors)

07 ISOTOPE AND RADIATION SOURCES↗

U.S. Department of Energy Office of Legacy Management Calibration Facilities - 12103

This paper describes radiometric calibration facilities located in Grand Junction, Colorado, and at three secondary calibration sites. These facilities are available to the public for the calibration of radiometric field instrumentation for in-situ measurements of radium (uranium), thorium, and potassium. Both borehole and hand-held instruments may be calibrated at the facilities. Aircraft or vehicle mounted systems for large area surveys may be calibrated at the Grand Junction Regional Airport facility. These calibration models are recognized internationally as stable, well-characterized radiation sources for calibration. Calibration models built in other countries are referenced to the DOE models, which are also widely used as a standard for calibration within the U.S. Calibration models are used to calibrate radiation detectors used in uranium exploration, remediation, and homeland security. (authors)

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Air Pathway Modeling of the E-Area Low-Level Waste Facility at the Savannah River Site - 12253

This investigation was initiated to address a concern expressed by the Department of Energy's Low Level Waste Disposal Facility Federal Review Group (LFRG) Review Team during their review of the 2008 E-Area Performance Assessment (PA). The concern was the potential for overlapping of atmospheric plumes, emanating from the soil surface above SRS LLW disposal facilities within the E-Area, to contribute to the dose received by a member of the public during the Institutional Control (IC) period. The implication of this concern was that the dose to the maximally-exposed individual (MEI) located at the SRS boundary might be underestimated during this time interval. To address this concern a re-analysis of the atmospheric pathway releases from E-Area was required. A new atmospheric release model (ARM) capable of addressing the LFRG plume overlap concern was developed. The conceptual approach to assessing the atmospheric dose to a member of the public from E-Area LLW disposal facilities is to perform sub-surface simulations of the release of volatile radionuclides from the waste zones through the overlying engineered barriers to determine a flux rate at the land surface. Then, atmospheric dispersion of the radionuclide flux is simulated in an atmospheric transport model to compute air concentrations in the vicinity of the hypothetically exposed individual. A re-analysis of atmospheric dispersion portion of the atmospheric pathway releases was not undertaken, however the Dose Release Factors (DRF's) previously computed in a atmospheric transport study were retained to convert the new surface emanation fluxes (computed with the ARM) into doses received by the MEI at the appropriate points of compliance (POC). In this way, the dose received by the MEI could be compared to the maximum permissible dose level, defined in DOE Order 435.1 as being 100 uSv/yr (10 mrem/yr). The main conclusion of this study is that for atmospheric releases from the E-Area disposal facilities, plume overlap does not cause the total dose to the MEI at the SRS boundary during IC to exceed the PA performance objective. This conclusion directly addresses the LFRG PA review team issue. Furthermore, even though the LFRG comment did not express concern for such overlap to occur during the post-Closure period, applying the 100% plume overlap strategy to atmospheric releases during this period also demonstrates that the PA performance objective for the MEI will also not be exceeded during that time-frame either. (authors)

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Groundwater Treatment at the Fernald Preserve: Status and Path Forward for the Water Treatment Facility - 12320

Operating a water treatment facility at the Fernald Preserve in Cincinnati, Ohio-to support groundwater remediation and other wastewater treatment needs-has become increasingly unnecessary. The Fernald Preserve became a U.S. Department of Energy Office of Legacy Management (LM) site in November 2006, once most of the Comprehensive Environmental Response, Compensation, and Liability Act environmental remediation and site restoration had been completed. Groundwater remediation is anticipated to continue beyond 2020. A portion of the wastewater treatment facility that operated during the CERCLA cleanup continued to operate after the site was transferred to LM, to support the remaining groundwater remediation effort. The treatment facility handles the site's remaining water treatment needs (for groundwater, storm water, and wastewater) as necessary, to ensure that uranium discharge limits specified in the Operable Unit 5 Record of Decision are met. As anticipated, the need to treat groundwater to meet uranium discharge limits has greatly diminished over the last several years. Data indicate that the groundwater treatment facility is no longer needed to support the ongoing aquifer remediation effort. (authors)

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Construction of the Largest Radionuclide Commingled Plume Groundwater Treatment Facility for the Department of Energy at the Hanford Site - 12411

CH2M Hill Plateau Remediation Company (CHPRC) has constructed the largest groundwater treatment systems of its kind throughout the DOE Complex at the Hanford Site in an accelerated manner with American Recovery and Reinvestment Act (ARRA) funds. This complex, one of a kind groundwater treatment facility in Washington State has also attained Leadership in Energy and Environmental Design (LEED) Gold certification. The original concept for the 200 West Area groundwater treatment facility was a 6100 liter per minute (1,600 gallon per minute) facility. With additional ARRA funding, the plant design was improved to construct a 9500 liter per minute (2,500 gallon per minute) facility with expansion areas up to 14,000 liter per minute (3,750 gallon per minute). The current design will remove 53 percent more mass per year for faster clean-up. It is also expected to treat extracted groundwater to 25 percent or less than the Record of Decision-specified limit which improves Monitored Natural Attenuation (MNA) effectiveness. (author)

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Development of an Integrated Leachate Treatment Solution for the Port Granby Waste Management Facility - 12429

The Port Granby Project (the Project) is located near the north shore of Lake Ontario in the Municipality of Clarington, Ontario, Canada. The Project consists of relocating approximately 450,000 m{sup 3} of historic Low-Level Radioactive Waste (LLRW) and contaminated soil from the existing Port Granby Waste Management Facility (WMF) to a proposed Long-Term Waste Management Facility (LTWMF) located adjacent to the WMF. The LTWMF will include an engineered waste containment facility, a Wastewater Treatment Plant (WTP), and other ancillary facilities. A series of bench- and pilot-scale test programs have been conducted to identify preferred treatment processes to be incorporated into the WTP to treat wastewater generated during the construction, closure and post-closure periods at the WMF/LTWMF. (authors)

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A Framework to Assess Advanced Reactor Spent Fuel Management Facility Deployment

Previous planning and prioritization for LWR SNF management investigated the risks and uncertainties of deploying facilities such as consolidated interim storage [1, 2, 3, 4]. As part of that work, activities and milestones were collected into success precedence diagrams that charted a path to achieving facility deployment [1]. In that framework, activities are any research, development, design, or decision required to achieve an intermediate goal; milestones are activity endpoints and mark the completion of deliverables. Milestones can be thought of as achievements required to reach the final goal of facility deployment; activities are the means by which milestones are accomplished. In planning, activities and milestones are compiled into comprehensive flow charts that visualize the steps necessary for deployment. This framework has been used to quantify risks, timelines, and costs of deploying SNF management facilities.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Sub-drain Water Treatment Facility for Reduction of Accumulated Waste Water Amount at the Fukushima NPS Site - 17572

At the Fukushima Daiichi Nuclear Power Station site, water treatment facility special for sub-drain and groundwater drain has been constructed by Tokyo Electric Power Company Holdings, Inc. and Hitachi-GE Nuclear Energy, Ltd., and it has been operated to remove radionuclides from the pumped groundwater. The facility consists of three kinds of equipment for collecting, purifying and transferring. The purification equipment removes radionuclides contained in the pumped groundwater. The purification equipment consists of filters for removal of solids and colloidal particles, and adsorbents for removal of ionic radionuclides. Five adsorption vessels are installed into the equipment; three vessels have adsorbent to remove Cs and Sr simultaneously, the fourth vessel has adsorbent to remove Sb and for the last has adsorbent to remove heavy metals. The vessels for Cs and Sr are operating as a so-called 'merry-go-round'. For the rational operation of the equipment, a simulation code has been developed to calculate the Sr concentration of outlet water which determines the replacement timings of the Cs-Sr adsorption vessels. The simulation code has been applied to planning of vessel replacement during the water treatment facility operation. The facility started operation in September 2015, and treated the pumped groundwater since then. As of October 2016, about 211,000 m{sup 3} of groundwater had been treated. (authors)

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Managing work flow and logistic at waste processing facilities using the waste compliance and tracking system - 15392

Work flow and logistics at a busy radioactive waste processing complex or permitted treatment, storage, and disposal facility (TSDF) can pose a monumental challenge. An efficient operation requires good communication between engineering, logistics, and waste operators. The Los Alamos National Laboratory (LANL) has implemented an application that facilitates seamless communication of work flow requirements, between engineering, logistics, and waste operations personnel in the field. The Waste Compliance and Tracking System (WCATS), a comprehensive waste management system designed at LANL, provides four key elements to support logistics: (a) the container work path, (b) directed unit operation requests, (c) notification of pending operations, and (d) real-time status tools for office and field workers. The combination of these elements allows everyone to function as a team, with a shared knowledge of what is needed to accomplish facility objectives. The first element is like a road map indicating which unit operations are needed and in what sequence they should be performed; this is referred to as a 'work path'. It automatically routes a waste item or container from operation to operation. For example, a given work path might indicate that waste items require radiological survey, radioassay, and a technical review, in that order. When the work path is assigned to a container, the system enforces the correct order of operations. Directed unit operation 'requests', the second element, fills a gap between pre-planned, formal 'work path' activities and the need for flexibility to direct preparatory operations or deal with unexpected issues, like staging or mining containers in preparation for a shipment or transferring containers from one storage unit to another to clear a path for building maintenance. Logistics engineers prepare these 'requests', and the system monitors the status and completion of the work. The third element, notifications, allows team members to subscribe to and receive notice that an operation is pending, initiated, or complete. This functionality supports a range of communication options, including e-mail, cell phone, pager, or application in-box messaging. Notifications allow waste operations personnel to multi-task, and remain in the loop on the status of facility-wide activities. Finally, the fourth element provides tools that communicate work path pending operations and directed requests to field workers on their mobile computer, allowing them to mine or pick containers from storage units, and leverage the capabilities of a bar-code scanner to avoid selection mistakes. Oversight and summary tools are provided, allowing logistics personnel to monitor work path and request task status, identify work-flow bottlenecks, and maximize the efficiency of waste operations. The Waste Compliance and Tracking System (WCATS) provides an innovative, comprehensive set of tools that allow large-scale radioactive waste processing facilities to manage logistics, maximize efficient use of the workforce, and create a team environment, where everyone from management to the waste handlers have an understanding of the work load and what needs to be accomplished. (authors)

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Siting considerations for a deep borehole disposal facility - 15403

This paper describes considerations for siting and designing a facility for deep borehole disposal of spent nuclear fuel (SNF) and/or high-level radioactive waste (HLW). Technical considerations include geological, hydrogeochemical, and geophysical characteristics that are related to the suitability of the site for deep drilling and borehole construction, waste emplacement activities, waste isolation (seals and surrounding geology), and long-term safety of the deep borehole disposal system. Logistical factors to be considered include: local or regional availability of drilling contractors (equipment, services, and materials) capable of drilling a large-diameter hole to approximately 5,000 m depth; construction of surface facilities and waste handling and emplacement equipment; legal and regulatory requirements associated with drilling, operation, and post-closure; and access to transportation systems. Social and political considerations include the distance from population centers and the support or opposition of local and state entities and other stakeholders to the facility and its operations. These technical, logistical, and socio-political factors are examined in the context of a consent-based siting process for a deep disposal borehole, which would be the first phase in developing an operating facility. (authors)

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Cigeo, The French Geological Disposal Facility Project: Preliminary Design (APS) Phase - 16038

The Cigeo project has been in the works for 25 years. Numerous studies have been conducted, increasingly associated with the Meuse/Haute-Marne site, with further specific research thanks to direct access to the Callovo-Oxfordian clay formation from the underground laboratory of Bure-Saudron. These studies and research initially aimed to demonstrate the feasibility of the repository. They also helped gain a high level of understanding of phenomena to support design studies and demonstrate safety. Transition to the industrial phase began with the development of a plan for delivering waste to the facility for disposal. The plan introduced sequencing for the various types of waste to be disposed of, and was optimised to determine the size of inspection, transfer and handling facilities. In describing the life of the repository and therefore the vision for its operation, it has become obvious that our generation should not impose choices on future generations. We must provide them with reference technical solutions, with the financial resources to implement them. It is also our duty to begin the construction and initial operating phases. However, because the facility will operate over several generations, we must leave a degree of flexibility so that they may reassess the options that we define and adopt their own solutions, as necessary. They will also benefit from operational experience gathered as facility operations develop. This is the context in which the preliminary design phase is being finalised in preparation for the detailed design phase, with the aim of gradual commissioning during the latter part of the next decade. (authors)

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