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[en] The latest version of the University of Toronto Glacial Systems Model (UofTGSM) was employed in the development of data sets describing the evolution of surface boundary conditions above a potential spent fuel repository over the course of a 122.5 kyr cycle of glaciation. The new data sets build increased confidence upon the previous UofTGSM generated data sets that Peltier (2006) supplied for this purpose. The components of the UofTGSM have been updated to a framework reflecting the current state-of-the-art, and a new strategy has been adopted to preserve consistency with observations independently of detailed assumptions about ice-sheet dynamics. A mass-balance adjustment is employed to nudge the ice-thickness solution towards the observationally well-validated ICE-6GC reconstruction, and dynamical variability can be analyzed in the context of ensembles with different exponential relaxation time-scales. This approach is used to diagnose ice thickness, permafrost thickness, basal temperature, meltwater production, lake depth, and other two dimensional, time-varying fields from a reference solution along with corresponding local error estimates. Beyond reflecting significant numerical advances that enabled the new UofTGSM to better represent basal processes, ice-shelves, temperate ice-water mixtures and other physics, the new results benefit from the many new measurements that constrained ICE-6GC (and therefore, indirectly, the nudged paleoclimate simulations). Nudging offers a more practical approach to leading-order data assimilation and error estimation than Bayesian calibration, which was employed in Peltier (2006), and which will continue to be of use in more detailed explorations of observationally constrained model parameter spaces. Rather than consisting of discrete time-series at the sites of hypothetical spent-fuel repositories, the new dataset also includes time-varying two-dimensional geographic distributions covering all of Canada. (author)
[en] This Quality Assurance Plan (QAP) provides the overall Quality Assurance (QA) program requirements, technical planning, and general quality practices to be applied to the U.S. Department of Energy (DOE) Environmental Management (EM) Nevada Program Soils Activity. The QAP requirements are consistent with the Quality Systems for Environmental Data and Technology Programs–Requirements with Guidance for Use (ANSI/ASQ, 2004); the Intergovernmental Data Quality Task Force Uniform Federal Policy for Quality Assurance Project Plans (IDQTF, 2005); and 10 Code of Federal Regulations (CFR) 830.120, Quality Assurance (CFR, 2017a), which apply to specific activities performed under the Soils Activity. The EM Nevada Program owns and is responsible for maintaining this QAP. Individual participants are responsible for implementing the requirements of this QAP in accordance with their own approved programs, processes, plans, and procedures. If a participant’s requirement document differs from this QAP, the stricter requirement will take precedence.
[en] Comparing the costs of different power generation technologies has become one of the main arguments used by proponents of specific sources and those seeking to find the best approach to plan the expansion of electrical systems. However, this approach, taken alone for public energy policy making, is far from simple and can lead to unwanted and unexpected results. How much does it cost? It seems like a simple question. However, when it comes to competing power generation technologies, it is an extremely challenging question. Generation costs include many variables: capital, fuel, location, waste disposal, environmental impact, interconnection, reliability, intermittency, and other external and systemic costs. No two technologies are alike. System costs are often divided into the following four broadly defined categories of profile costs (also referred to as utilization costs or backup costs), balancing costs, grid costs and connection costs: – Profile costs refer to the increase in the generation cost of the overall electricity system in response to the variability of VRE output. – Balancing costs refer to the increasing requirements for ensuring the system stability due to the uncertainty in the power generation (unforeseen plant outages or forecasting errors of generation). – Grid costs reflect the increase in the costs for transmission and distribution due to the distributed nature and locational constraint of VRE generation plants. – Connection costs consist of the costs of connecting a power plant to the nearest connecting point of the transmission grid.
[en] This technical report documents the results of the Phase 2 Geological Mapping activity completed in 2016 as part of the Phase 2 Geoscientific Preliminary Assessment, to further assess the suitability of the White River area to safely host a deep geological repository. This study followed the successful completion of the Phase 1 Geoscientific Desktop Preliminary Assessment (AECOM, 2014), which identified withdrawal areas for further field studies. Geological mapping was completed within and around two of these withdrawal areas. The purpose of the Phase 2 Geological Mapping is to advance understanding of the bedrock geology of the withdrawal areas, with an emphasis on observation and analysis of bedrock structure and lithology. Information collected during Phase 2 Geological Mapping also helps to identify areas of exposed bedrock, assess overburden thickness, and identify surface constraints within and around the withdrawal areas, which might affect suitability. Observations were conducted at select locations that were accessed using existing secondary roads, trail networks and waterbodies, as well as some off-trail hiking. The two areas were mapped over a total period of 55 days by one mapping team using a consistent workflow and standardized digital data collection system. Observations were made at a total of 373 locations in and around the two withdrawal areas, including 169 locations in the Strickland pluton area and 204 locations in the Anahareo Lake pluton area. A digital data collection protocol was applied and observations were compiled into a GIS compatible database. This includes information on bedrock character (lithology, magnetic susceptibility, gamma ray spectrometry, structure, rock strength), fracture character, bedrock exposure and surface constraints. This report details the field observation for the withdrawal areas. (author)
[en] The operation of multi purpose reactor and supporting laboratories (RSG-LP) at Serpong Nuclear Area (KNS) may produce a large amount of liquid effluent. Liquid effluent is nonradioactive liquid waste that potentially contaminated by radioactive material. To ensure that the liquid effluent meets the requirement for released to the environment, it's collected in Comprehensive Release Monitoring (PBT) pool. Liquid effluent in the pool is analyzed of its activity concentration and its physics-chemical parameter. Liquid effluent can be released to the environment if its activity under the radioactive release threshold (NBLR), and its physics-chemical parameter under quality standard threshold. The problem faced on the liquid effluent management is the limited capacity of pool. It can make the liquid effluent management service queue, and the operation of RSG-LP will be disturbed. To solve this problem, the improvement of management system must be done so the liquid effluent management will be more effective and efficient. Web base on-line service system is used as innovation to reduce the response time of service request, and to make the management of liquid effluent transfer to PBT pool easier. The on-line service system can reduce service time up to 30 % of conventional system service time. (author)
[en] This technical report documents the results of the Phase 2 Geological Mapping activity completed in 2017 as part of the Phase 2 Geoscientific Preliminary Assessment, to further assess the suitability of the Elliot Lake and Blind River area to safely host a deep geological repository. This study followed the successful completion of the Phase 1 Geoscientific Desktop Preliminary Assessment (Golder, 2014), which identified three withdrawal areas for further field studies. Geological mapping was completed within and around one of these withdrawal areas. The purpose of the Phase 2 Geological Mapping is to advance understanding of the bedrock geology of the withdrawal area, with an emphasis on observation and analysis of bedrock structure and lithology. Information collected during Phase 2 Geological Mapping also helps to identify areas of exposed bedrock, assess overburden thickness, and identify surface constraints within and around the withdrawal areas, which might affect suitability. Observations were made at a total of 271 select locations that were accessed using existing secondary roads, trail networks and waterbodies, as well as some off-trail hiking. The area was mapped over a total period of 32 days by two mapping teams, using a consistent workflow and standardized digital data collection system. A digital data collection protocol was applied and observations were compiled into a GIS-compatible database. This includes information on bedrock character (lithology, magnetic susceptibility, gamma ray spectrometry, structure, and rock strength), fracture character, bedrock exposure and surface constraints. This report details the field observation for the mapped withdrawal area. (author)
[en] This report summarises the key findings of the Greenland Analogue Project (GAP), a collaborative research project conducted between 2008 and 2013 by the national nuclear waste management organisations in Sweden (SKB), Finland (Posiva) and Canada (NWMO). The primary aims of the GAP were to enhance scientific understanding of glacial processes and their influence on both surface and subsurface environments relevant to the performance of deep geological repositories for spent nuclear fuel in crystalline shield rock settings. Based on its size, relative accessibility, and crystalline shield bedrock, the Greenland Ice Sheet (GrIS) was selected by the GAP as a natural analogue for glaciation processes expected to reoccur in Fennoscandia and Canada over Deep Geological Repository (DGR) safety-relevant timeframes. (author)
[en] This report presents the methods, collected datasets, and the interpretations completed for the Greenland Analogue Project (GAP), a collaborative research project conducted between 2008 and 2013 by the national nuclear waste management organisations in Sweden (SKB), Finland (Posiva) and Canada (NWMO). The primary aims of the GAP were to enhance scientific understanding of glacial processes and their influence on both surface and subsurface environments relevant to deep geological repository (DGR) performance in crystalline shield rock settings. Based on its size, relative accessibility, and crystalline shield bedrock, the Greenland Ice Sheet (GrIS) was selected by the GAP as a natural analogue for glaciation processes expected to reoccur in Fennoscandia and Canada over DGR safety-relevant timeframes. The GAP study area is located east of Kangerlussuaq village on the west coast of Greenland and covers approximately 12,000km2, of which approximately 70% is occupied by the GrIS. To advance understanding of glacial hydrogeological processes, GAP research activities included both extensive field work and modelling studies of the GrIS, focused into three main subprojects: SPA) surface-based ice sheet studies; SPB) ice drilling and direct studies of basal conditions; and SPC) geosphere studies. The main objectives and activities of these subproject areas are provided below: SPA) Surface-based ice sheet studies aimed to improve the current understanding of ice sheet hydrology and its relationship to subglacial hydrology and groundwater dynamics. This work was based primarily on indirect observations from the ice sheet surface of the basal hydrological system, to obtain information on the parts of the ice sheet which contribute water for groundwater infiltration. Project activities included quantification of ice sheet surface-water production, as well as an evaluation of how water is routed from the ice surface to the interface between the ice and the underlying bedrock. Methods employed include: remote sensing, automatic weather station network, GPS measurements of ice motion, ground-penetrating radar and seismics. SPB) Ice drilling and direct studies of basal conditions also aimed to improve understanding of ice sheet hydrology and groundwater formation based on direct observations of the basal hydrological system, paired with numerical ice sheet modelling. Specific processes were investigated, including: 1) thermal conditions within and at the base of the ice sheet; 2) generation of meltwater at the ice/bedrock interface; and 3) hydrologic conditions at the base of the ice sheet. Activities included ice drilling of multiple holes at three locations on the ice sheet, at distances up to thirty kilometers from the ice sheet terminus, to assess drainage, water flow, basal conditions and water pressures at the interface between the ice and bedrock. SPC) Geosphere investigations focused on groundwater flow dynamics and the chemical and isotopic composition of water at depths of 500 metres or greater below ground surface, including evidence on the depth of permafrost, redox conditions and the infiltration of glacial meltwater into the bedrock. Deep and inclined bedrock boreholes were drilled through the permafrost in the vicinity of the ice sheet margin. The boreholes were hydraulically tested and instrumented to allow hydrogeologic and hydrogeochemical monitoring. The nature of ground conditions under a proglacial lake was also investigated, to assess if areas of unfrozen ground within the permafrost (taliks) may act as a potential pathway for exchange of deep groundwater and surface water. A wide range of methods were applied by SPC to study the above including: geological, geophysical and surface water investigations, as well as bedrock borehole investigations. (author)
[en] Highlights: • Geochemical modeling, and particularly chemical thermodynamics, is particularly important in performance assessment. • The NEA TDB Project provides a database of high quality, used extensively worldwide. • Several national nuclear programs have drawn heavily on the NEA TDB as a basis upon which they built their own datasets. • The NEA TDB could be envisioned as an approach that could potentially be used in broader areas of environmental interest, nuclear and beyond. - Abstract: For the last 30 years, the NEA Thermochemical Database (TDB) Project (www.oecd-nea.org/dbtdb/) has been developing a chemical thermodynamic database for elements relevant to the safety of radioactive waste repositories, providing data that are vital to support the geochemical modeling of such systems. The recommended data are selected on the basis of strict review procedures and are characterized by their consistency. The results of these efforts are freely available, and have become an international point of reference in the field. As a result, a number of important national initiatives with regard to waste management programs have used the NEA TDB as their basis, both in terms of recommended data and guidelines. In this article we describe the fundamentals and achievements of the project together with the characteristics of some databases developed in national nuclear waste disposal programs that have been influenced by the NEA TDB. We also give some insights on how this work could be seen as an approach to be used in broader areas of environmental interest.
[en] Sea level change over the global system has been studied by various observations during the historical period. Sea level rise would be one of the most significant potential impacts of climate change if the current trend of sea level rise (SLR) due to global warming continues to increase for the upcoming decades. The objective was to identify spatial and temporal of radioactive waste facilities that would be affected if sea level rise to happen. Data on contour was obtain from ASTERGDEM NASA, relevant government agency and was also mapped digitally. GIS application is very useful for the radioactive waste sector in planning of facing a geomorphological evolution. (author)