РОССИЙСКАЯ АКАДЕМИЯ НАУК Институт проблем безопасного развития атомной энергетики

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1 РОССИЙСКАЯ АКАДЕМИЯ НАУК Институт проблем безопасного развития атомной энергетики RUSSIAN ACADEMY OF SCIENCES Nuclear Safety Institute (IBRAE) Engineering and Radiation Surveys of Dumped Structures as the Key Element in the Development of a Complex Program for Radiological Remediation of the Arctic Seas Antipov S.V., Vysotskiy V.L. (IBRAE RAS), Sivintsev Yu.V. (RRC KI ) 0

2 РОССИЙСКАЯ АКАДЕМИЯ НАУК Институт проблем безопасного развития атомной энергетики RUSSIAN ACADEMY OF SCIENCES Nuclear Safety Institute (IBRAE) The Presentation Plan 1. What is found at the bottom of the Arctic Seas (SNF & radwaste), and where exactly? 2. What is the danger of the dumped/sunken structures? 3. What pre-dumping operations did they underwent? 4. What is the forecast of degradation of their shielding barriers? 5. What steps are needed for radio-ecological remediation of the Arctic Seas? 6. What is the purpose of the IERS of the dumped/sunken structures? 7. What is to be studied within the IERS framework? 8. What is missing for the work deployment? 9. Conclusions 1

3 РОССИЙСКАЯ АКАДЕМИЯ НАУК Институт проблем безопасного развития атомной энергетики RUSSIAN ACADEMY OF SCIENCES Nuclear Safety Institute (IBRAE) WHAT IS FOUND AT THE BOTTOM OF THE ARCTIC SEAS More then structures containing SNF and RW were dumped at the Arctic Seas by the USSR and Russia. They include: three (3) Nuclear Submarines (NS) five (5) Reactor Compartments (RC) with Nuclear-Powered Installations (NPI) a barge with a NS reactor 19 ships with Solid RadWaste (SRW) 735 unpacked radioactive structures and units 2

4 SNF-containing Radiation-hazardous Structures Sunken and Dumped at the Arctic No Structure Location Year of dumping 1 Komsomolets NS (1 reactor with SNF) 2 K-159 NS (2 reactors with SNF) 3 K-27 NS (2 reactors with SNF-LMC) 4 Reactor compartment of NS No 901 (2 reactors with SNF) 5 Reactor compartment of NS No 285 (2 reactors: 1 with SNF) 6 Reactor of NS No 421 (with SNF) Novozemelskay Sea Trench 7 Shielding assembly of Lenin NIB (a reactor with SNF) Depth, m Norwegian Sea Barents Sea Stepovoy Bay Abrosimov Bay Abrosimov Bay Tsyvolki Bay 1967 up to 50 3

5 Locations of Dumping of SNF-containing structures at Bays of Novaya Zemliya Новоземельская впадина Abrosimov Bay: 1 RC of NS No 901, 2 - RC of NS No 285; Stepovoy Bay: 3 К-27 NS; Novozemelskaya Sea Trench: 4 reactor of NS No 421; Tsyvolky Bay: 5 shielding assembly of Lenin NIB. 4

6 РОССИЙСКАЯ АКАДЕМИЯ НАУК Институт проблем безопасного развития атомной энергетики RUSSIAN ACADEMY OF SCIENCES Nuclear Safety Institute (IBRAE) No real radiation hazard from radiation structures dumped in the Arctic The results of radionuclide analysis of thousands of bottom-sediment samples taken by dozens of sea expeditions at the locations of dumping do not differ from the average data for the World Ocean. A series of investigations conducted by experts of Russian institutions, EU, IAEA and NATO have revealed no scenarios according to which the dumped structures may present a radiation hazard in the near future. Potential hazards may become real hazards only in the cases of irresponsible economic activities or terrorist attacks. Most important are: the psychological and the ethic factors 5

7 Arrangement Aboard a Barge and Mothballing of SNF- containing reactor of NS No 421 furfural concrete furfural 6

8 A Pontoon with SNF-containing Shielding Assembly of Lenin NIB Prepared for Dumping Mouth of the submersion 1 system Caisson lid shielding assembly 7

9 RC with mothballed SNF-containing reactors of NS No 901 prepared for dumping floating domes reactor compartment light hull floating domes 8

10 Structure of Dumped SRW (> packages) Package type Activity per unit package Number of packages Containers with SRW < 0.1 Ci ~ 40% Containers with SRW Ci ~ 50% Containers with SRW 1-10 Ci ~ 10% Ships with SRW in holds Container thickness Ci < 1 % (19 pieces) Types of Dumped Containers Container amount Steel 3 mm ~ 90% Steel 5 mm ~ 10% Filling mode Container amount In bulk ~ 90% Cementation or bituminization ~ 10% 9

11 Degradation stages of the outer shells of dumped NS reactor compartments initial state partial degradation full degradation 10

12 Time of Corrosion Damage Light Hull, Floating Domes RC Front Partitions Strong Hull of RC tp 22 ± 7 year t p 44 ± 10 year tp 110 ± 23 year tp time of through-hole generation due to pitting; degradation times: 1 minimal, 2 mean, 3 maximal 11

13 Release of Man-made Radionuclides from SNF of К-159 Nuclear Submarine 1 start of radionuclide release 2-3 generation of pitting holes in the primary circuit 4-5 release of radionuclides from SNF 6-7 degradation of outer surfaces of reactor vessel 7-8 degradation of reactor internals 9-10 degradation of reactor vessel cladding degradation of reactor cap cladding 12

14 Location of K-159 NS at the Sea Bottom Accelerated corrosion damage and mechanical degradation of pipelines of Nuclear-Powered Installations (NPI) are possible due to metal deformations and stresses 13

15 Corrosion Damage of Metal Containers and SRW- containing Ships Dumped at the Arctic 3 mm 5 mm 10 mm Degradation time: 1 minimal, 2 mean, 3 maximal 14

16 РОССИЙСКАЯ АКАДЕМИЯ НАУК Институт проблем безопасного развития атомной энергетики RUSSIAN ACADEMY OF SCIENCES Nuclear Safety Institute (IBRAE) The Sequence of Steps Needed for Radiological Remediation of the Arctic Seas Formulation of a general goal and specific tasks of radiological remediation of the Arctic Seas. Generalization and analysis of available data on sunken/dumped structures containing SNF and RW. Target setting for necessary extra-surveys (IERS) of such structures. Development and approval of a Concept for radiological remediation of the Arctic Seas. Development of a Strategy and a Program of radiological remediation of the Arctic Seas. Execution of radiological remediation of the Arctic Seas. 15

17 РОССИЙСКАЯ АКАДЕМИЯ НАУК Институт проблем безопасного развития атомной энергетики RUSSIAN ACADEMY OF SCIENCES Nuclear Safety Institute (IBRAE) Obtaining of input information within the IERS framework is necessary for: development of a Strategy and a Program of work; drafting a list of the needed machinery and equipment; drawing up the Terms of Reference for the development of design documentation; construction of special equipment for raising, shipment, dismantling and handling of SNF & RW; building-up of a package of safety-related documents; development and agreement of a Remediation Program (a Tentative Plan) with the authorities regulating the use of nuclear power and with the relevant supervisory bodies. 16

18 РОССИЙСКАЯ АКАДЕМИЯ НАУК Институт проблем безопасного развития атомной энергетики RUSSIAN ACADEMY OF SCIENCES Nuclear Safety Institute (IBRAE) In the course of IERS one needs to analyze the available information and perform supplementary investigations on: engineering-and-technical conditions of structures from the viewpoint of feasibility of their remediation using available methods; conditions of staying the dumped/sunken structures at sea bottom to clarify the very possibility of their raising; the capability of ensuring nuclear, radiation and environmental safety at all work stages; achievement of the end goal using the available methods and equipment via justification and selection of an optimal implementation option. 17

19 РОССИЙСКАЯ АКАДЕМИЯ НАУК Институт проблем безопасного развития атомной энергетики RUSSIAN ACADEMY OF SCIENCES Nuclear Safety Institute (IBRAE) WHAT IS MISSING TODAY? No Concept for of the Arctic Seas from potentially hazardous structures with SNF & RW has been developed yet (dumped structures, water areas, objectives, terms, remediation stages etc. are not determined); No official decision on radiological remediation of the marine environment has been taken; Neither the owners nor the executors have been appointed; Basic requirements for IERS and IERS program have not been developed; Sanitary regulations (the criteria) for remediation of the marine environment do not exist; A Remediation program for the Arctic Seas do not exist either; The problem itself has not been taken into consideration by any Federal Target Program (no financing). 18

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21 CONCLUSIONS: The performed field investigations demonstrate that to date Russian structures dumped with SNF & RW at the Arctic present no real hazard to the population and the environment. Potential hazards depend on the status of shielding barriers, the processes of their degradation and the transfer of radio nuclides in sea water. Further location of SNF-containing structures at the bottom of the Arctic Seas with no integrated Program for their handling is unacceptable from the environmental and the ethic standpoints. The presence of nuclear materials in shallow-water conditions increases the problem acuteness yet more due to possible terrorist threats. There is a need for developing scenarios of radio-ecological situation changes in the Arctic, arranging sea expeditions to perform Integrated Engineering and Radiation Surveys (IERS), analysis of different options for handling the dumped structures taking into account radio-ecological, social, political, mental and ethic factors. International co-operation in the field under consideration is indispensable. 19