Research and Engineering Center for Radiological, Hydrogeological and Ecological Studies, National Academy of Sciences of Ukraine, Kyiv, Ukraine

Transcription

1 UDC N. I. Proskura 1, V. M. Shestopalov 2, L. I. Zinkevich 1, Yu. A. Shibetskii 2, Z. M. Alekseieva 3, E. I. Zhebrovskaia 4 1 State Agency of Ukraine for Exclusion Zone Management, Chornobyl, Ukraine 2 Research and Engineering Center for Radiological, Hydrogeological and Ecological Studies, National Academy of Sciences of Ukraine, Kyiv, Ukraine 3 State Scientific and Technical Center for Nuclear and Radiation Safety, Kyiv, Ukraine 4 Institute of Environmental Geochemistry, National Academy of Sciences of Ukraine, Kyiv, Ukraine Radioactive Waste Classification for Long-term Disposal Safety The objective of this paper is to familiarize the stakeholders with suggestions elaborated within INSC Project U4.01/08-C to update the radioactive waste classification for disposal purposes. The suggestions are based on analysis of Ukrainian radioactive waste management practices, laws and regulations in force and experience of countries with developed nuclear industry in the introduction of new classification approaches for radioactive waste disposal in different repositories. The suggested classification divides radioactive waste into classes to meet the requirements for disposal in repositories of four various types: surface repository (landfill-type facilities with limited regulatory control), near-surface repository with a system of engineered barriers, underground repository located at intermediate depths and deep geological repository. According to Ukrainian legislation, there is no prohibition on radioactive waste disposal in repositories of these types. In this regard, radioactive waste is suggested to be divided into the following classes: non-radioactive waste, natural radioactive materials (NORM), very low-level waste (VLLW), low-level waste (LLW), 1

2 intermediate-level waste (ILW), high-level waste (HLW) and spent radiation sources (SRS). The authors propose approaches to determine criteria for differentiation of the classes presented in the updated classification. The updated classification is shown to provide considerable saving of efforts since radioactive waste is classified according to optimum methods of disposal and types of repositories. The economic benefit has been calculated. Steps for introduction of the updated classification into practice of radioactive waste management in Ukraine have been planned. Keywords: radioactive waste classification, types of repositories, radioactive waste, safety criteria. The modern practice of radioactive waste (RAW) management is based on applying different options of waste treatment and conditioning, its short-term and long-term storage, as well as possible disposal methodologies. Strategy and consistent policy of radioactive waste management (considering volume and characteristics of waste streams), as well as possible disposal methodologies, are determined at the state level to achieve the ultimate objective of radioactive waste management - safe disposal. In this context implementing RAW classification as a component of integral waste management system, which would consider long-term risks of waste disposal in used repository types, becomes especially urgent. In recent years, Ukraine has taken steps to optimize radioactive waste management, including those aimed at improving RAW classification schemes for disposal [1]. The experts of consortium DBE TECHNOLOGY GmbH (Germany), ANDRA (France), COVRA (Netherlands), ENRESA (Spain) and SKB International AB (Sweden) involving Ukrainian experts implemented project INSC U4.01/08-C "Improvement of RAW classification system in Ukraine" in in Ukraine 2

3 under assistance of the European Commission within the program of International Cooperation on Nuclear Safety [2]. Beneficiaries of the project were the ministries and departments responsible for safe radioactive waste management: State Agency for Management of the Exclusion Zone, Ministry of Energy and Coal Industry of Ukraine, Ministry of Health of Ukraine. Objective of this paper is to familiarize a wide range of stakeholders with proposals on modifying current RAW classification for its disposal developed under project INSC U4.01/08-C. Proposals are based on radioactive waste management in Ukraine, provisions of current regulations, experience of countries with developed nuclear industry on developing and implementing classification schemes aimed at disposal of radioactive waste in repositories of different types. Practical needs in the most economic waste isolation methodology under meeting the required safety level are the basis of proposals on modifying the classification scheme. The main proposals for changing current Ukrainian classification of radioactive waste (as regards its disposal) [2] are presented, advantages and benefits of implementing these changes into practice on RAW management are analyzed. BACKGROUNDS TO IMPROVE RAW CLASSIFICATION SCHEME FOR DISPOSAL The strategy for radioactive waste management adopted by most countries with developed nuclear energy is focused on their retention and isolation from the environment for the period of waste potential hazard. Therefore, waste is collected and sorted by streams with similar radiological characteristics, processed and conditioned, as well as, if necessary, stored for further release from regulatory control or disposed, which should provide passive RAW isolation, protection of human health and environment [3 5]. 3

4 Due to traditional practices, RAW management at sites of Ukrainian nuclear power plants, in particular collection and sorting, was not focused at meeting the safety requirements at subsequent management stages, including long-term storage and disposal. Similar situation exists at the enterprises of conventional branches. Until recently, RAW and spent radiation sources (SRS) were disposed at the sites of UkrDo "Radon" inter-regional specialized plants without considering and assessing possible long-term radiological consequences of disposal. It should be noted that besides RAW generated in practical activity, large RAW volume of emergency origin was generated after Chernobyl accident. The last is characterized with high concentration of alpha-emitting radionuclides and concentrated mainly in the Chernobyl Exclusion Zone (CEZ). At the state level program and strategic documents of Ukraine [6, 7] envisage construction of processing facilities, long-term storage facilities for radioactive waste and SRS, as well as repositories for all types and categories of radioactive waste within the legislation in force. At the same time, it is planned to dispose all RAW in Ukraine, including Chernobyl waste, in the Chernobyl Exclusion Zone. The Law of Ukraine "On Radioactive Waste Management" [8] divides waste into two types: short-lived and long-lived waste. Short-lived RAW can be disposed in near-surface and surface repositories. Long-lived RAW should be disposed in stable geological formations. This provision is presented in detail in regulations [9, 10]. According to "Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management" ratified by the Law of Ukraine [11] the principle of human health and environment protection should be met taking into account RAW potential radiological hazard in the distant future. Disposal risks to human, including that in the distant future, are associated with the reliability of RAW isolation from accessible environment with the system of natural and artificial barriers [3, 5, 12]. In other words, requirements for barrier effectiveness should correspond to radiological hazard of disposed waste. Since waste management includes a number of interrelated operations, it is important to take into 4

5 account disposal requirements already at the stage of RAW generation to ensure a consistent process and exclude re-sorting and additional conditioning of waste streams. This determines the relevance of implementing the RAW classification scheme as a part of integral waste management system. Such a classification scheme should provide selection of economically viable sequence of radioactive waste management, focused on safety objectives during disposal. Document [2] pays attention to the fact that large volume of low-level RAW is accumulated (expected) in Ukraine. It can be disposed in a more economical way - in repositories without complex system of engineered barriers, as is customary in many Western countries. This is one of the reasons for modifying current Ukrainian RAW classification for disposal, in particular introducing very low-level radioactive waste. OBJECTIVE OF NEW RAW CLASSIFICATION SCHEME Modified scheme of RAW classification for disposal presented in [2] assumes its division into classes according to acceptance criteria for disposal in the repositories of four types: surface (analogue of landfills used for disposal of household waste); near-surface with engineered barrier system; underground at intermediate depth; in-depth geological. Taking this into account it is proposed to divide radioactive materials into the following classes (Fig. 1): non-radioactive waste; waste containing natural radionuclides called waste of natural radioactive materials (hereinafter NORM); very low-level waste (VLLW); low-level waste (LLW); 5

6 intermediate-level waste (ILW); high-level waste (HLW); spent radiation sources (SRS). Specific activity Heat release 2 kw*m -3 High-level waste Intermediate-level waste Specific alpha-activity in 300 years 4000 kbq*kg -1 Low-level waste Vektor Radiological index RI 10 Very low-level waste Buryakivka Exemption and release level Non-radioactive waste Half-life period disposal Fig. 1. Graphical representation of RAW classification scheme in Ukraine for Thus, instead of waste division into two types (short- and long-lived), for disposal of which current classification assumed near-surface repositories and deep geological repositories [9, 10], new classification scheme divides radioactive wastes into four classes: VLLW, LLW, ILW, and HLW. Besides these four RAW classes, there is a class, which management does not require consideration of radiological characteristics (so-called non-radioactive waste 1 ). NORM and SRS are also considered as separate classes. 1 In IAEA publication, 2009 "Classification of Radioactive Waste, IAEA Safety Standards, No. GSG-1" this waste is called "exempted" waste. 6

7 Implementing new RAW classification scheme for disposal does not assumes changes in RAW division into categories (criterion - dose power or specific activity), groups (criterion exemption levels), and types (criterion - aggregate state), as it is established in [9, 10], as well as any changes in radiation and health & safety procedures established in [9, 13]. DESCRIPTION OF NEW RADIOACTIVE WASTE SCHEME Non-radioactive waste. It is proposed to include objects and substances to this class: a) activity of which does not exceed exemption levels; b) released from regulatory control. Such waste can be disposed without considering radiological characteristics. Exemption and release levels established in the national regulations [9, 13] can serve as the upper limit of referring waste to this class. For Chernobyl emergency waste (hereinafter - Chernobyl waste) it is recommended to establish special release levels substantiated due to special conditions of RAW confinement in CEZ, which determines specific human exposure scenarios and, correspondingly, permissible boundary levels of radionuclide activity in waste. NORM. Contains only natural radionuclides (for example, waste of uranium ore extraction, processing, and enrichment, waste of oil and gas industry). Usually characterized with low activity levels, but high content of long-lived radionuclides. Large volume of NORM traditionally not processed as radioactive is accumulated in Ukraine. Currently, there is no consensus on NORM management at the international levels. As a rule, the majority of NORM in many Western countries is managed beyond the nuclear legislation with complete meeting the radiation safety standards. Taking into account large volume of this waste, usually NORM are not disposed as radioactive waste. In individual cases, taking into account safety analysis results, some NORM lots can be disposed in repositories for LLW or ILW. 7

8 VLLW. This waste class is not separated in current classification of [9, 10]. VLLW includes radioactive waste activity of which exceeds the exemption and release levels (the lower limit for referring waste to VLLW), but according to its radiological characteristics does not require disposal in complex systems with multibarrier protection. VLLW can be disposed in the simplest surface repositories similar to landfill of industrial waste. At the same time, it is assumed that administrative control period will not exceed 100 years. A trend of implementing VLLW class is observed in most countries with developed nuclear energy programs. Significant international experience in construction and operation of repositories for VLLW is already accumulated. According to assessments in [2], the most part of waste generated after operation (in Western countries to 70 %) and dismantling of nuclear reactors (in Western countries to 50 %) can be classified as VLLW. The main part of Chernobyl waste (to 60 %) also can belong to VLLW, for example radioactive waste concentrated in the point of decontamination waste collection outside CEZ and in certain points of temporary confinement. LLW. Radioactive waste under disposal of which in near-surface repositories equipped with the multi-barrier protection system safety objectives can be reached within the administrative control period not over 300 years. LLW class corresponds approximately to "short-lived waste" type separated by current Ukrainian classification [9, 10]. Such waste is generated in the operation of nuclear power plants and dismantling of nuclear reactors. Significant part of Chernobyl waste (near 40 %), radiological characteristics of which are similar to that in RWDS "ChNPP Stage 1", can also refer to LLW. There is significant international experience in construction and operation of near-surface repositories for LLW. It should be outlined that not all radioactive waste belonging to short-lived waste according to [9, 10] will be included to LLW, since significant volume of the 8

9 short-lived waste will be classified as VLLW after implementing modified classification scheme. ILW. Radioactive waste requiring disposal in the repositories at intermediate or deep depth together with HLW. ILW class approximately corresponds to "longlived waste" type [9, 10]. Ukraine accumulated significant ILW volume, for example, waste from Shelter, RWDS "Pidlisnyi" in CEZ. The international experience on construction and operation of ILW repositories is very limited (WIPP repositories, USA, and Konrad, Germany). Construction of special repositories for ILW is planned in France and Sweden. HLW. Radioactive waste that can be disposed exceptionally in in-depth repositories. It is characterized with high specific activity ( ТBq m 3 ), heat release exceeding 2 kw m 3, and high content of long-lived radionuclides. HLW includes vitrified waste from processing of spent nuclear fuel (SNF), as well as SNF, if it is considered as waste. This waste class is also separated in current RAW classification of Ukraine [9, 10], but it also includes a part of RAW with high specific activity and heat release not over 2 kw m 3. The international experience on construction and operation of HLW repositories is absent. SRS. IAEA determines SRS as a "special waste type" [14]. In Ukraine there are a lot of SRS and their number constantly grows. Separation of SRS as an individual class is substantiated by potential risks of their disposal. At the same time SRS can be disposed in repositories for VLLW, LLW, ILW or HLW depending on SRS parameters and results of repository safety assessment. CLASS LIMITS Waste acceptance criteria (WAC) for all types of repositories, this waste to be disposed, should be developed to establish boundaries between the classes. WAC 9

10 development is an iterative process relying on safety assessments, which should consider the actual characteristics of waste, site, and repository design. RAW acceptance criteria should include quantitative limits for general and specific activity of individual radionuclides or radionuclide groups. These limits are actually quantitative boundaries between separate classes. Conceptual dependence of the mentioned quantitative boundaries on radionuclide activity and half-life period is shown in Fig.1. The release and exemption levels represent the lower numerical boundary for VLLW, and acceptance criteria of repositories for VLLW determine numerical boundary between VLLW and LLW classes. WAC of LLW repositories determine, in turn, the boundary between LLW and ILW classes. In case of joint disposal of ILW and HLW in deep geological repository numerical boundary between them can lose practical value. Taking into account that it was not planned to use all the mentioned disposal systems in Ukraine, as well as considering the absence of appropriate disposal concept general waste acceptance criteria (GWAC) were developed within project INSC U4.01/08-C [2] to divide waste into proposed classes based on similar international programs on waste disposal. RAW class boundaries presented in [2] (general waste acceptance criteria) reflect actual data obtained for standard repository designs developed in accordance with the best international practices. GWAC can be used as an important parameter in long-term planning of economic and financial aspects of RAW management. Objective of GWAC determination is to provide sorting and preliminary preparation of accumulated and generated RAW so as to accept finally obtained waste for disposal as soon as appropriate methodology will be determined. Proposed RAW classification scheme covers all radioactive waste existing in Ukraine. Applying in the future new nuclear technologies can require rejustification of the class boundaries according to additional parameters. 10

11 Approach for Morvilliers VLLW repository (France) applied in determining WAC was used in determining the upper VLLW boundary. It is based on calculating radiological index for disposed RAW lot: RI n i A 1 10 i group k where A i specific activity of i-radionuclide in RAW; group k number of a group (values from 0 tо 3 is accepted), to which i-radionuclide is referred. It is considered that radiation safety will be ensured if radiologic index will not exceed 1 on average for waste lot (for individual lot RI to 10 is allowed). The main feature of this approach is referring radionuclide to a particular group. Group number corresponds to the decimal order of the value of the maximum permissible radionuclide specific activity (MPSA) in disposed waste. MPSA values are determined according to condition of non-exceeding radiological safety criteria for the scenarios of personnel and public exposure during repository operation and after closure. It is accepted that administrative control period does not exceed 100 years, after which access to a disposal site is not limited. Document [2] determines MPSA for 143 nuclides and presents the information on radionuclide division into groups. Consequences of vehicle accidents, fire in trench, and other exposure scenarios during repository operation, as well as exposure scenarios after repository closure and site release from regulatory control (roadbuilding, housing construction at the site of former repository, etc.) were considered to determine MPSA. It was found that limits of the maximum permissible activities of radionuclides are determined in exposure scenarios during operation. This means that the upper boundary of VLLW class actually does not depend on site conditions and can be used for any repositories of this RAW. Maximum permissible total specific activity of alpha-emitting radionuclides 4000 kbq kg-1 (in separate package) at the end of administrative control at 400 kbq kg 1 on average in repository is accepted as the upper LLW boundary due to IAEA recommendations [14]. 11

12 As regards RAW division into ILW and HLW the international practice [14] uses criterion of heat release level 2 kw m 3, but not limits of general and specific activity of individual radionuclides due to safety analysis for ILW repositories. It is recommended to use the value of specific activity of alpha-emitting radionuclides (not less than 4000 kbq kg 1 ) as the lower ILW boundary. The upper boundary is determined by heat release level less than 2 kw m 3. Classification of waste generated after Chernobyl accident represents a special problem. Chernobyl waste is characterized with higher content of long-lived radionuclides comparing to operational waste from nuclear power plants. Although the volume of Chernobyl waste is significant, its separation as a special class is considered not reasonable [2]. Instead, it is proposed to distribute Chernobyl waste by classes according to its specificity and characteristics and the fact that it will be disposed in CEZ. The problem can be solved through Chernobyl waste disposal in CEZ in the repositories with less strict WAC. Thus, Chernobyl VLLW can be disposed in CEZ in near-surface repositories similar to RAW disposal site (RWDS) "Buryakivka" of trench type, LLW - in near surface repositories with multi-barrier protection system similar to repositories at "Vector" site [15]. At the same time special exemption and release levels of Chernobyl waste will serve as the lower boundary. Special less strict WAC for Chernobyl VLLW and LLW accumulated in CEZ are based on limited access to CEZ [16] that will exclude a set of exposure scenarios in long-term safety assessments [17]. These WAC are based on assessing radiation impact on critical population groups outside CEZ. Special WAC for Chernobyl VLLW can be determined based on WAC for "Buryakivka" and for LLW - based on acceptance criteria of the repositories at "Vektor" site (specially equipped nearsurface solid RAW disposal facility for Chernobyl waste or SRW-1 and SRW-2). In [2] it is noted that special WAC should be applied only for Chernobyl waste. At the same time WAC at "Buryakivka", which also serve as the lower boundary to refer 12

13 Chernobyl waste to LLW, can be the upper VLLW boundary. WAC of "Vektor" repositories are applicable for the upper LLW boundary. ASSESSMENT OF ECONOMIC BENEFIT In compliance with [2] implementing VLLW class can give savings for disposal up to 6 billion in western prices and to 400 million in Ukrainian prices. Implementing new RAW disposal scheme will reduce total cost of RAW disposal in Ukraine by times (Fig. 2). Proposed classification Cost of RAW disposal, mln. of r.u. Current classification Cost of RAW disposal, mln. of r.u. SR (VLLW) NSR (LLW) Without repository construction at intermediate depth NSR (all LLW+NPP ILW) DGR (CEZ ILW+ all HLW) DGR (ILW and HLW) TOTAL: 70 mln. of r.u. Emergency RAW contribution 86% Symbols: Regular use of nuclear energy TOTAL: 70 mln. of r.u. Emergency RAW contribution 86% SR (VLLW) TOTAL: 18 mln. of r.u. Emergency RAW contribution 84% NSR (LLW) r.u. SR NSR GRID Accident at ChNPP Relative unit to express cost (1 r.u. = cost of disposal of 1 m 3 of VLLW Surface repository Near-surface repository Geological repository at intermediate depth DGR (HLW) GRID (ILW) Including repository construction at intermediate depth DGR Deep geological repository Cost of RAW disposal, mln. of r.u. Fig. 2. Assessing economic benefit of new RAW classification scheme Thus, new classification scheme can ensure significant savings by distributing radioactive waste in compliance with the best disposal practices and repository types. 13

14 Particular work on RAW sorting and characterization should be performed already after its generation to use such advantages. This may temporarily imply additional costs. However, to sort and characterize RAW immediately after its generation is much easier and cheaper than to sort and characterize mixed waste from general repository much later. This work and associated costs are not a consequence of implementing proposed new classification scheme. It is inevitable and predetermined by the requirements of current legislation [8 10]. Thus, looking forward, implementing proposed new waste classification scheme will not cause any additional or excess expenses. STEPS TO IMPLEMENT MODIFIED CLASSIFICATION SCHEME In compliance with [2] implementing new classification scheme consists in the following: а) develop necessary amendments to legislative and regulatory documents and include new classification to regulation system; b) implement new classification in RAW management practice. The main idea of amending the regulations is based on the fact that there is no need to develop a separate document on radioactive waste classification. It is reasonable to introduce proposed new classification by amending the fundamental document - Law of Ukraine "On Radioactive Waste Management" [8]. This will initiate a chain of appropriate amendments in related laws and regulations including OSPU-2005 [10] and NRBU-97/D-2000 [9]. In transition period different classifications will exist in parallel. This will provide the necessary time reserve to specify RAW boundaries when acceptance criteria for all required repositories will be developed. The existing practice of waste characterization and sorting at sites is not sufficient to select the best methodology of waste disposal. Often waste characterization is limited to measuring common (β/γ) activity and (or) corresponding 14

15 dose power of waste or waste packages. Characterization with determining detailed radionuclide composition of not processes waste and appropriate RAW sorting not only contributes to implementing new RAW classification scheme, but will also provide disposal of all this waste. When applying requirements according to new RAW classification scheme for disposal during characterization and sorting it is possible to combine solution of the main problem as regards future waste disposal (data obtaining for safety substantiation) and significant economic benefit of implementing new classification scheme. Background for amending waste characterization and sorting procedures is developing preliminary general acceptance criteria for each waste class. On the basis of Enterprise should be developed requirements for sorting and characterization of waste for recycling and receive data to verify compliance with the waste acceptance criteria for disposal. Sorting and characterization requirements should be developed for following waste processing and data obtaining to check waste compliance with the criteria of waste acceptance for disposal based on GWAC. RAW characterization and sorting should begin at generation point. Waste of the same stream is similar according to composition and nuclide content, which simplifies and reduces sampling and measuring work. For specific waste stream often it is possible to establish correlations between content of easily measured radionuclides (for example, 137 Cs and 60 Co) and other radionuclides which it is difficult to measure. It is very difficult and expensive to characterize and sort RAW later after joint temporary storage of mixed waste of different origin. Besides, this will result in significant uncertainties in determining RAW nuclide composition. In extreme cases, mixed waste will be disposed as LLW in a geological repository at intermediate depth with correspondent additional costs. 15

16 Conclusions Modified scheme of RAW classification for disposal proposed within project INSС-U4/01/08-С allows optimization of RAW classification system in Ukraine. Approaches to determine boundaries between the classes of modified classification system are proposed. It is shown that new classification system can ensure significant savings by distributing radioactive waste in compliance with the best disposal practices and repository types. Economic effect of new classification system is evaluated. Steps on implementing new classification scheme into radioactive waste management in Ukraine are outlined. References 1. General Provisions for Ensuring Safety of Radioactive Waste Management: Draft: Approved by Director General of JSC "Radiation Protection Institute of the Academy of Technological Sciences of Ukraine" (Ident. Code 111U009794). P. 67. (Ukr) 2. Proposals for Implementing New System of Radioactive Waste Classification into Ukrainian Regulations: Project INSC U4.01/08-C, November Electro-optical disk (CD-ROM). (Ukr) 3. Disposal of Radioactive Waste. Vienna: International Atomic Energy Agency, p. (IAEA Safety Standards Series No. SSR-5).(Eng) 4. NP General Provisions for Ensuring Safety of Radioactive Waste Disposal into Geological Disposal Facilities//Ofitsiynyi Visnyk Ukrainy (Official Bulletin of Ukraine) No. 43. (Ukr) 5. NP Requirements for Site Selection for the Facility for Disposal of Radioactive Waste//Ofitsiynyi Visnyk Ukrainy (Official Bulletin of Ukraine No. 95.(Ukr) 16

17 6. Law of Ukraine "On Nationwide Environment-oriented Program of Radioactive Waste Management in Ukraine"//Vidomosti Verkhovnoi Rady Ukrainy (Bulletin of Verhovna Rada of Ukraine) No. 5. P. 8. (Ukr) 7. Strategy for Radioactive Waste Management//Order of CMU No. 990-р. (Ukr) 8. Law of Ukraine "On Radioactive Waste Management"//Vidomosti Verkhovnoi Rady Ukrainy (Bulletin of Verhovna Rada of Ukraine) No. 27. P (Ukr) 9. Radiation Safety Standards of Ukraine, Supplement: Radiation Protection against Ionizing Radiation Sources (NRBU-97/D-2000). State Health and Safety Standards: DGN Official publication. P.80. (Ukr) 10. State Sanitary Rules : Basic Sanitary Rules for Radiation Safety of Ukraine (OSPU-2005). Approved by Order of Ministry of Health of Ukraine No. 54 dated 02 February 2005//Ofitsiynyi Visnyk Ukrainy (Оfficial Ukrainian Bulletin). 24 June No.23. P.197. (Ukr) 11. On ratification of Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management: Approved by the Law of Ukraine No III dated 20 April 2000//Vidomosti Verkhovnoi Rady Ukrainy (Bulletin of Verhovna Rada of Ukraine) No. 31. (Ukr) 12. The Safety Case and Safety Assessment for the Disposal of Radioactive Waste: Specific Safety Guide. Vienna: IAEA, p. (IAEA Safety Standarts No. SSG-23). (Eng) 13. Health and Safety Standards "Levels of Radioactive Material Exemption from Regulatory Control"//In book: Procedure for Exemption of Radioactive Waste from Regulatory Control within the Practical Activity: NP K.: State Nuclear Regulatory Inspectorate of Ukraine, Р (Ukr) 17

18 14. Classification of Radioactive Waste: Safety Guide. Vienna: IAEA, P.68 (IAEA Safety Standarts, No. GSG-1). (Eng) 15. The First Stage of Complex of Plants for Decontamination, Transportation, Treatment, and Disposal of Radioactive Waste from the Territories Contaminated as a Result of ChNPP Accident (Code Name Vektor. І Stage Disposal of Radioactive Waste): Design (Conceptual)/Ministry of Emergencies of Ukraine (Ukr) 16. Law of Ukraine "On the Legal Order of the Territories Contaminated by the Chernobyl Disaster"/Vidomosti Verkhovnoi Rady Ukrainy (Bulletin of Verhovna Rada of USSR) No. 16. (Ukr) 17. Alekseeva Z. M., Kondratyev S. M., Nikolaiev Ye. О., Mykolaichuk О. А., Makarovska О. А., Rybalka N. V. Comprehensive Safety Assessment of Radioactive Waste Management at Vector site//nuclear and Radiation Safety Ed. 2 (58). P (Ukr) 18