Intermediate Level Radioactive Waste Research Articles

Comprehensive Development Plans for the Low- and Intermediate-Level Radioactive Waste Disposal Facility in Korea and Preliminary Safety Assessment

경주 방사성폐기물 처분시설은 향후 80만 포장물을 처분할 계획이며 다양한 처분방식 및 관리형태를 가진 복합계가 될 것이다. 본 논문에서는 전체부지 처분용량(80만 포장물) 처분시설의 단계별 개발에 따른 영향을 평가하기 위하여 처분시설 종합개발계획(안)에 따른 예비안전성평가를 수행하였다. 각 시나리오에 대한 안전성평가결과 처분시설의 성능목표치를 만족하였다. 다만, 전체처분시설의 안전성 평가결과에 중준위 방사성폐기물로 인하여 1단계 동굴 처분시설이 가장 크게 영향을미치므로 처분시설의 안전성 향상을 위하여 처분방사능량제한 설정 등 관리방안이 필요하다. Safety Case 단계별 구축을 통하여 중·저준위 방사성폐기물 처분시설 종합개발 과정에서 인지된 불확실성을 저감하여 안전성을 증진 시킬 수 있을 것으로 판단된다.

Long-term safety of the extended SFR - Methodology and conclusions from the SR-PSU project

ABSTRACTSince 1988 the Swedish Nuclear Fuel and Waste Management Co. operates a repository for low- and intermediate-level short-lived radioactive waste, SFR, in Forsmark, Sweden. Due to decommissioning of the nuclear power plants additional storage capacity is needed. In December 2014, an application to extend the repository was therefore submitted. One key component of this application was an assessment of post-closure safety of the extended SFR. For this safety assessment, a methodology based on that developed by SKB for the spent nuclear fuel repository was used and the impact of the degradation of repository components, the evolution of the surface system and changes of future climate on the radiological safety of the repository was assessed over a period of 100,000 years. The central conclusion of the SR-PSU safety assessment is that the extended SFR repository meets requirements on protection of human health and of the environment that have been established by the Swedish radiation safety authority for the final disposal of radioactive waste. Furthermore, the design of the repository was shown suitable for the waste selected and the applied methodology suitable for the safety assessment.

Semi-Tomographic Gamma Scanning Technique for Non-Destructive Assay of Radioactive Waste Drums

Segmented gamma scanning (SGS) and tomographic gamma scanning (TGS) are two traditional detection techniques for low and intermediate level radioactive waste drum. This paper proposes one detection method named semi-tomographic gamma scanning (STGS) to avoid the poor detection accuracy of SGS and shorten detection time of TGS. This method and its algorithm synthesize the principles of SGS and TGS. In this method, each segment is divided into annual voxels and tomography is used in the radiation reconstruction. The accuracy of STGS is verified by experiments and simulations simultaneously for the 208 liter standard waste drums which contains three types of nuclides. The cases of point source or multi-point sources, uniform or nonuniform materials are employed for comparison. The results show that STGS exhibits a large improvement in the detection performance, and the reconstruction error and statistical bias are reduced by one quarter to one third or less for most cases if compared with SGS.

Reactive transport modelling of shale-bentonite interactions in a hypersaline environment

Bentonite is a widely considered sealing material for radioactive waste repositories and its behaviour has been studied in a variety of settings. In Ontario Power Generation's Deep Geological Repository (DGR) design for low and intermediate level radioactive waste, a reference 70:30 bentonite/sand mixture is the most voluminous component of the proposed shaft sealing system, in addition to cement- and asphalt-based components. In this study, the long-term durability of the bentonite in contact with sedimentary wall rocks of the shaft and highly-saline porewater was assessed. The possible significance of reactions between bentonite and high-salinity, magnesium-rich porewater for the sealing properties of bentonite has hitherto received less attention than reactions such as smectite illitization, iron-bentonite interactions and cement-bentonite interactions.Fully-coupled reactive transport models were developed to simulate the evolution of the interface between the bentonite/sand mixture and the Georgian Bay Shale, which forms the wall rocks of the shaft overlying the Cobourg Formation (limestone), within which it is proposed to locate the repository. The highly saline nature of the shale porewater led to a Pitzer approach being used to model mineral solubilities. The ‘base case’ simulation suggests that there will be rapid partial replacement of Namontmorillonite with Ca-montmorillonite in the bentonite/sand, with K-montmorillonite then replacing Ca-montmorillonite over longer timescales (tens of thousands of years). Over 100,000 years, minor alteration of the primary minerals at the shaft seal-rock interface occurred in this model, resulting in a reduced porosity alteration zone with a thickness of a few centimetres. The main alteration product in the bentonite/sand was saponite, whereas in the shale, it was analcime (which was included as a representative sodium-rich framework silicate). A number of variant cases were also developed that explored the effects of model discretisation and geochemical assumptions (controls on dissolved silica concentrations) on calculated system evolution. The variation in discretisation led to minor differences in the evolution of the system, especially with regard to porosity. The assumption that quartz buffers the initial dissolved silica concentrations instead of amorphous silica (the ‘base case’ assumption) resulted in kaolinite forming along with saponite in the bentonite/sand, and kaolinite forming in preference to analcime in the host rock. However, none of the simulations resulted in a significant increase in bentonite-sand porosity over 100,000 years and most of the thickness of the bentonite/sand shaft seal remained unaltered. Hence the models suggest that the performance of the DGR bentonite/sand shaft seals in contact with hypersaline porewater should not be detrimentally affected.

Microbial impacts on 99mTc migration through sandstone under highly alkaline conditions relevant to radioactive waste disposal

Geological disposal of intermediate level radioactive waste in the UK is planned to involve the use of cementitious materials, facilitating the formation of an alkali-disturbed zone within the host rock. The biogeochemical processes that will occur in this environment, and the extent to which they will impact on radionuclide migration, are currently poorly understood. This study investigates the impact of biogeochemical processes on the mobility of the radionuclide technetium, in column experiments designed to be representative of aspects of the alkali-disturbed zone. Results indicate that microbial processes were capable of inhibiting 99mTc migration through columns, and X-ray radiography demonstrated that extensive physical changes had occurred to the material within columns where microbiological activity had been stimulated. The utilisation of organic acids under highly alkaline conditions, generating H2 and CO2, may represent a mechanism by which microbial processes may alter the hydraulic conductivity of a geological environment. Column sediments were dominated by obligately alkaliphilic H2-oxidising bacteria, suggesting that the enrichment of these bacteria may have occurred as a result of H2 generation during organic acid metabolism. The results from these experiments show that microorganisms are able to carry out a number of processes under highly alkaline conditions that could potentially impact on the properties of the host rock surrounding a geological disposal facility for intermediate level radioactive waste.

SYNTHESIS OF GEOCHEMICAL AND FRACTURE MINERAL STUDIES RELEVANT TO A DEEP GEOLOGICAL REPOSITORY FOR NONFUEL WASTES AT CHALK RIVER

As part of a feasibility study under the Nuclear Legacy Liabilities Program, the geochemistry of the crystalline bedrock at the Chalk River Laboratories site has been investigated to examine the suitability of the bedrock to host a potential deep geologic repository, termed a Geologic Waste Management Facility, for the long-term management of intermediate-level radioactive wastes for Canadian Nuclear Laboratories, formerly Atomic Energy of Canada Limited. Characterization of the groundwater and fracture-filling minerals are important considerations in assessing how the geochemical environment would affect the performance and safety of such a facility. Regional groundwater chemistry at the site has evolved over time by groundwater mixing and by rock–water interactions. Collaborative studies with the University of Waterloo and the United States Geological Survey have provided data for whole-rock, fracture minerals, and groundwater isotope systematics. The sampled groundwaters appear in general to be geologi...

Sorption of plutonium to bacteria and fungi isolated from groundwater and clay samples

Preliminary studies of Pu(V) sorption to site-specific microorganisms isolated from the Triassic clay selected as an engineered barrier for the near surface low and intermediate level radioactive waste repository and from groundwater at the expected site were carried out. Adsorption of Pu(V) by bacteria attained the maxima values of 82–84 % at pH 6–7. The maximum adsorption values of Pu of about 100 % were found for Penicillium chrysogenum at pH 4.1. Bioreduction of Pu(V) to Pu(IV) by Bacillus cereus was observed, while any Pu(III) was not found in the system.

The Russian Strategy of using Crystalline Rock as a Repository for Nuclear Waste

Research Article| August 01, 2016 The Russian Strategy of using Crystalline Rock as a Repository for Nuclear Waste Nikolai P. Laverov; Nikolai P. Laverov 1Laboratory of Radiogeology and Radiogeoecology, Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences119017 Moscow, RussiaE-mail: laverov@presidium.ras.ru; syud@igem.ru; btk@igem.ru; malk@igem.ru Search for other works by this author on: GSW Google Scholar Sergey V. Yudintsev; Sergey V. Yudintsev Search for other works by this author on: GSW Google Scholar Boris T. Kochkin; Boris T. Kochkin Search for other works by this author on: GSW Google Scholar Victor I. Malkovsky Victor I. Malkovsky Search for other works by this author on: GSW Google Scholar Author and Article Information Nikolai P. Laverov 1Laboratory of Radiogeology and Radiogeoecology, Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences119017 Moscow, RussiaE-mail: laverov@presidium.ras.ru; syud@igem.ru; btk@igem.ru; malk@igem.ru Sergey V. Yudintsev Boris T. Kochkin Victor I. Malkovsky Publisher: Mineralogical Society of America First Online: 13 Jul 2017 Online Issn: 1811-5217 Print Issn: 1811-5209 © 2016 by the Mineralogical Society of America Elements (2016) 12 (4): 253–256. https://doi.org/10.2113/gselements.12.4.253 Article history First Online: 13 Jul 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Nikolai P. Laverov, Sergey V. Yudintsev, Boris T. Kochkin, Victor I. Malkovsky; The Russian Strategy of using Crystalline Rock as a Repository for Nuclear Waste. Elements 2016;; 12 (4): 253–256. doi: https://doi.org/10.2113/gselements.12.4.253 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyElements Search Advanced Search Abstract The first Russian underground repository for high- and intermediate-level radioactive waste (HLW and ILW, respectively) will be built in the crystalline Archean granite–gneisses at Yeniseisky (Krasnoyarsk region, Siberia). The geological and hydrogeological characteristics of this site are similar to those found in Forsmark (Sweden) and Olkiluoto (Finland). However, the Russian disposal strategy is different. HLW will be disposed in the form of an aluminophos phate glass and ILW (with long-lived radionuclides) will be cemented. Preliminary research on all aspects of repository design (stability of waste forms, waste packages, and bentonite buffer; evaluation of the geologic barrier; and simulation of radionuclide transport by groundwater) will be performed at an on-site underground research laboratory. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Leaching behaviour of low Ca:Si ratio CaO–SiO2–H2O systems

A dynamic leaching study of the dissolution of low calcium to silicon ratio (C/S) calcium–silicate–hydrate (C–S–H) systems with initial C/S ranging from 0.2 to 0.6 has been undertaken. Dissolution was studied in demineralised water at 25°C to a degree of leaching of 2.5m3kg−1. These C–S–H gels show remarkably similar behaviour during early leaching stages, giving an equilibrated pH of ~9.9 and a solution phase C/S of ~0.29. Over longer times, C–S–H gels with C/S>0.29 evolve, on leaching, towards a congruent dissolution point with a solid C/S close to 0.84 (consistent with tobermorite) and pH~10.8. C–S–H gels with C/S<0.29 become increasingly silica-rich on leaching but maintain an alkaline pH>9.5 down to at least C/S=0.07 (the lowest ratio reached). For C/S<0.7, chemical modelling and X-ray diffraction data support an explanation of the incongruent dissolution behaviour of the low C/S C–S–H gels based on the congruent dissolution of distinct amorphous silica and tobermorite-like C–S–H phases. Above C/S of 0.7, the dissolution data are well described by an ideal solid solution model for the C–S–H phases. These results are of relevance to the consideration of the disposal of silica-rich vitrified intermediate-level radioactive wastes in cement-based concepts for geological disposal, where maintenance of alkaline pH values forms a key component of the chemical barrier to radionuclide migration. The implications are that the long-term pH buffering capacity provided by cementitious backfill materials would not be significantly affected by interactions with silica-rich wasteforms, which may lower the net C/S ratio of C–S–H phases, due to the natural tendency of these systems to restore congruent dissolution at pH10.8.

An assessment of Palaeogene and Neogene clay deposits in Denmark as possible host rocks for final disposal of low- and intermediate-level radioactive waste

Abstract In Denmark, mapping and preliminary investigations of Palaeogene and Early Neogene clay deposits have been performed over the past 5 years. The goal was to locate potential host rocks for the final disposal of low- and intermediate-level radioactive waste from the Danish Research Centre Risø, which has to be decommissioned within the next 5–8 years. Five areas with low-permeability Paleocene and Oligocene clay formations, situated in northern Jylland, NE Fyn and southern Lolland, not far from the Baltic coast at Femern Belt, have been suggested. The clay formations are between 75 and 150 m thick, and have large lateral distribution. They are covered by thin layers of glacial clayey tills and the shallow depth to the clay formations is attractive, partly because they are easy to access and partly because there are no groundwater aquifers situated above or below the clay deposits. The paper gives an overall review of the characteristics of the six different clay formations within four of the areas.

Measuring diffusion coefficients of dissolved He and Ar in three potential clay host formations: Boom Clay, Callovo-Oxfordian Clay and Opalinus Clay

Abstract For the long-term management of high- and intermediate-level radioactive waste and/or spent fuel, many countries prefer disposal in a geological repository. In Belgium, Switzerland and France, argillaceous formations are being explored as potential host formations for this purpose. In this context, knowledge of the diffusion coefficient of He is relevant within two research areas: first, diffusion coefficients are used in safety calculations to evaluate the balance between gas generation (mainly H 2 ) and gas dissipation; and, second, the diffusion coefficients of He and Ar are needed in the diffusion models of natural tracers. Owing to the lack of data on the diffusion coefficients of He and Ar for the different clay host formations, diffusion experiments with dissolved He and Ar were performed on Boom Clay, Opalinus Clay and Callovo-Oxfordian Clay. Samples were confined in a diffusion cell, and diffusion coefficients were measured by using the double through-diffusion technique. The diffusion coefficients ( D p or D pore ) for He in Boom Clay, Callovo-Oxfordian Clay and Opalinus Clay are 12.6×10 −10 , 4.51×10 −10 and 7.13×10 −10 m 2 s −1 , respectively. The diffusion coefficients for Ar in Boom Clay, Callovo-Oxfordian Clay and Opalinus Clay are 18.6×10 −11 , 4.06×10 −11 and 3.65×10 −11 m 2 s −1 , respectively.

Water, vapour and heat transport in concrete cells for storing radioactive waste

Water is collected from a drain situated at the centre of a concrete cell that stores radioactive waste at ‘El Cabril’, which is the low and intermediate level radioactive waste disposal facility of Spain. This indicates flow of water within the cell. 2D numerical models have been made in order to reproduce and understand the processes that take place inside the cell. Temperature and relative humidity measured by sensors in the cells and thermo-hydraulic parameters from laboratory test have been used. Results show that this phenomenon is caused by capillary rise from the phreatic level, evaporation and condensation within the cell produced by temperature gradients caused by seasonal temperature fluctuations outside. At the centre of the cell, flow of gas and convection also play a role. Three remedial actions have been studied that may avoid the leakage of water from the drain.

Prediction of Radionuclide Inventory for the Low- and Intermediate-Level Radioactive Waste Disposal Facility by the Radioactive Waste Classification

To meet nuclear regulatory requirements, more than 95% individual radionuclides in the low- and intermediate-level radioactive waste inventory have to be identified. In this study, the radionuclide inventory has been estimated by taking the long-term radioactive waste generation, the development plan of disposal facility, and the new radioactive waste classification into account. The state of radioactive waste cumulated from 2014 was analyzed for various radioactive sources and future prospects for predicting the long-term radioactive waste generation. The predicted radionuclide inventory results are expected to contribute to secure the development of waste disposal facility and to deploy the safety case for its long-term safety assessment.

Possible use of bisphenol-a polycarbonate in radioactive waste embedding

Frequent use of bisphenol-a polycarbonate in daily life results with a huge amount of polycarbonate waste. The proper utilization of this waste would be an environmental friendly approach. As polymeric materials are candidate materials for radioactive waste embedding, having an aromatic structure within the main chain, the bisphenol-a polycarbonate is a candidate material to be used as an embedding matrix for the confinement of low and intermediate level radioactive waste. This possibility would partly solve the problem of huge amount of waste generated due to the usage of polycarbonate.In this study, the possibility for the usage of bisphenol-a polycarbonate in radioactive waste management was investigated regarding to radiation stability and resistance. For that purpose, changes in the properties of polycarbonate irradiated with different doses were determined. Irradiations, which were carried out for the duration of more than 8 months with an initial dose rate of 993 Gy/h, ended with a total irradiation dose of 4341 kGy to the samples. A detailed characterization of irradiated polycarbonate samples were performed by tensile, DMA, TGA, ATR-FTIR, AFM, EDX and SEM tests. The modifications within the polymer matrix have been reported. The total dose at which bisphenol-a polycarbonate could resist regarding to mechanical properties was determined.

Assessing the oxidising effect of NaNO3 and NaNO2 from disposed Eurobitum bituminised radioactive waste on the dissolved organic matter in Boom Clay

In Belgium, compatibility studies are performed in view of the final disposal of nitrate-containing bituminised intermediate-level radioactive waste in Boom Clay, which is considered as a potential host formation. Due to the presence of large amounts of nitrate in the waste, a slow release of nitrate (and to a smaller extent also nitrite) into the Boom Clay is expected. Nitrate and/or nitrite reduction by redox-active components of the host rock may cause a geochemical perturbation of the clay and subsequently might affect its barrier function against the migration of radionuclides. This paper therefore addresses the possible oxidation of one of the main redox-active components of the Boom Clay, i.e. dissolved organic matter, by nitrate and nitrite. For this, abiotic and microbially mediated nitrate and nitrite reduction was studied during long-term batch tests (2–2.5 years) in Boom Clay pore water, containing 155 ± 15 mg C/l present as humic and fulvic acids. Changes in the reducing capacity of the DOM due to oxidation were assessed successfully using two oxidants, namely ferricyanide and ferric citrate. The results of these experiments indicate that an abiotic reaction between DOM and nitrate does not occur or is characterised by very slow kinetics. On the other hand, a slow microbial nitrate reduction to nitrite was observed and the associated oxidation of DOM was confirmed by a decrease in the (partial) reducing capacity of DOM for ferric citrate. In contrast to nitrate, nitrite was shown to oxidise DOM both abiotically and mediated by microbes through (chemo)denitrification, although these reactions also seem to occur only at a rather slow rate. No significant change in the maximally obtainable reducing capacity of DOM (using ferricyanide) was detected during any of the observed reactions, suggesting that the impact of such a slow heterotrophic nitrate reduction is very limited.

The Microbial Ecology of a Hyper-Alkaline Spring, and Impacts of an Alkali-Tolerant Community During Sandstone Batch and Column Experiments Representative of a Geological Disposal Facility for Intermediate-Level Radioactive Waste

ABSTRACTNaturally occurring hyper-alkaline springs and associated hyper-alkaline environments may have components that are analogous to a cement-based deep geological disposal facility (GDF) for intermediate level radioactive waste (ILW). Such high pH environments could give insights into the biogeochemical processes that could occur in the region of a GDF environment after the ingress of GDF-derived groundwater leads to the formation of a hyper-alkaline plume in the surrounding rock mass. This study focuses on the microbial community composition found at a highly alkaline spring near Buxton, Derbyshire, England, and the variation in community structure across spatially separated sample points of contrasting pH values (ranging from pH 7.5–13). Communities containing alkaliphilic and alkalitolerant bacteria were observed across the site by PCR amplification and 16S rRNA gene pyrosequencing and included members of the families Comamonadaceae and Xanthomonadaceae. At pH 13, the sequence library was dominated by Gammaproteobacteria of the families Pseudomonadaceae and Enterobacteriaceae. Bacterial communities from the site demonstrated the ability to reduce Fe(III) in microcosm experiments up to pH 11.5, suggesting the potential to reduce other metals and radionuclides of relevance to cement-encapsulated intermediate level radioactive waste (ILW) disposal. In laboratory column flow-through experiments, microbial communities present at the field site were also able to colonize crushed sandstone. Bacterial community composition varied between columns that had been supplied with alkali surface waters from the site amended with carbon (lactate and acetate, as proxies for products of cellulose degradation from ILW), and control columns that were not supplied with added carbon. Members of the family Clostridiaceae dominated the sequence library obtained from the carbon amended column inlet (45.8% of library), but became less dominant at the outlet (20.8%). Members of the family Sphingomonadaceae comprised 11.8% of the sequence library obtained from the control column inlet, but were not present in sediments collected from the column outlet, whereas the relative abundance of members of the family Comamonadaceae increased from the column inlet (35.2%) to the column outlet (57.2%). The spatial variation in community composition within the columns is indicative of discrete biogeochemical zonation in these flow-through systems.

Bacterial Diversity in the Hyperalkaline Allas Springs (Cyprus), a Natural Analogue for Cementitious Radioactive Waste Repository

The biogeochemical gradients that will develop across the interface between a highly alkaline cementitious geological disposal facility for intermediate level radioactive waste and the geosphere are poorly understood. In addition, there is a paucity of information about the microorganisms that may populate these environments and their role in biomineralization, gas consumption and generation, metal cycling, and on radionuclide speciation and solubility. In this study, we investigated the phylogenetic diversity of indigenous microbial communities and their potential for alkaline metal reduction in samples collected from a natural analogue for cementitious radioactive waste repositories, the hyperalkaline Allas Springs (pH up to 11.9), Troodos Mountains, Cyprus. The site is situated within an ophiolitic complex of ultrabasic rocks that are undergoing active low-temperature serpentinization, which results in hyperalkaline conditions. 16S rRNA cloning and sequencing showed that phylogenetically diverse microbial communities exist in this natural high pH environment, including Hydrogenophaga species. This indicates that alkali-tolerant hydrogen-oxidizing microorganisms could potentially colonize an alkaline geological repository, which is predicted to be rich in molecular H2, as a result of processes including steel corrosion and cellulose biodegradation within the wastes. Moreover, microbial metal reduction was confirmed at alkaline pH in this study by enrichment microcosms and by pure cultures of bacterial isolates affiliated to the Paenibacillus and Alkaliphilus genera. Overall, these data show that a diverse range of microbiological processes can occur in high pH environments, consistent with those expected during the geodisposal of intermediate level waste. Many of these, including gas metabolism and metal reduction, have clear implications for the long-term geological disposal of radioactive waste.

An evaluation of nuclide release from a trench-type LILW repository

A simple and effective model and a GoldSim (GoldSim, 2006) template program, by which a probabilistic safety assessment of a conceptual trench-type repository for low- and intermediate level radioactive waste (LILW) disposal can be carried out under various nuclide release scenarios, have been developed. To quantify the exposure dose rates due to nuclide release from the trench and transport through the various pathways possible in the near- and far-fields of the repository system under a base case and some alternative scenarios, illustrative evaluations for a comparison among the scenarios as well as a sensitivity of shortcut pathways generated due to earthquakes on the nuclide transport are made and demonstrated. To this end, by changing the conservative base case nuclide release scenario under which all portions of the cap of the trench are failed unconditionally and immediately after a closure of the repository, a total of four other alternative scenarios were separately evaluated for the total exposure dose rates to the farming exposure group and then compared to the base case results. Among them, an earthquake scenario shows a dominant behavior almost throughout the whole time span. To see the influence of all shortcut travel pathways that are assumed to be newly generated by this earthquake scenario, their sensitivities to the exposure dose rates to the farming exposure group were also made and compared to each other.

Hydrometallurgical Reprocessing of BREST-OD-300 Mixed Uranium-plutonium Nuclear Fuel

The duration of external fuel cycle of BREST-OD-300 reactor with mixed U-Pu nitride fuel (MNIT) including hydrometallurgical reprocessing should not exceed 3 years. An average burnup of the fuel should be 6% of heavy metal (HM) with the potential increase up to 10% HM. Therefore, the technology should provide the reprocessing of spent nuclear fuel (SNF) after less than 2 years cooling time and with fissile materials (FM) content of 10 – 15%. Pellets technology has been chosen for the MNIT fuel production. That means necessity to receive the recycled actinides oxides of high purification coefficient (∼ 106). Currently on a laboratory scale, the following process stages have been tested on the real products: actinide oxides production and rare-earth and trans-plutonium elements separation. Moreover, on a pilot scale the process of high level radioactive waste (HLW) and intermediate level radioactive waste (ILW) concentration by evaporation has been tested, as well as the Am-Cm separation. In 2015, the design of the MNIT SNF reprocessing facility has been started, placed at the JSC Siberian Chemical Plant site as a part of the pilot demonstration power complex (PDPC) with BREST-OD-300 reactor. MNIT SNF reprocessing plant (RP) should be put in operation after 2020.

Nuclear Waste Burial in Canada? The Political Controversy over the Proposal to Construct a Deep Geologic Repository

Canada’s newly minted federal minister of the environment, Catherine McKenna, decided on February 18, 2016 to delay the federal government’s decision on a proposal to construct a permanent repository for nuclear waste beneath the Bruce nuclear site, little more than a kilometre from Lake Huron. Officially called a ‘deep geologic repository’, or DGR, the facility is the brainchild of Ontario Power Generation. While it would not store fuel rods from nuclear plants, it would take in all other types of low- and intermediate-level radioactive wastes including concrete, equipment and protective gear from the continued operation and planned refurbishment of all Ontario’s 20 nuclear power reactors. While most of the studies and consultations were done when the Conservative government was in power, Minister McKenna has now delayed the decision pending more information and will seek a further extension for the review from cabinet at a later date. A federal panel appointed by then minister of the environment, Peter Kent, and the Canadian Nuclear Safety Commission gave its overall seal of approval to the controversial proposal in May 2015. The panel’s favourable view overcame a major regulatory hurdle in the construction of the DGR however since the panel released its decision after public hearings, political opposition to this plan has only grown and spread. Critics argue that low-level and intermediate-level waste from all Ontario’s nuclear reactors should not be stored so close to the source of 20 percent of the world’s surface fresh water. The proposal’s scientific and technical merits and demerits are already well documented in various reports and hearings, but more controversy is expected now that the federal minister of the environment has announced another setback to the proposal. We can probably expect more political debate and long delays.