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Seminar:Nuclear Risks - Safety and Security |
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Opening.
Professor Ole D. Lærum, Vice president of Norwegian Academy of Science and Letters
This symposium is one in a series of seven to celebrate the 150th anniversary of The Norwegian Academy of Science and Letters, and the second common with the Norwegian Polytechnic Society. The program committee decided to select topics of both controversial and scientific interest to the society. By doing so we intended to provide a better basis for public debate.
In this symposium we expect to get important new information about nuclear risks. Top experts are coming from different corners of the world. They will elucidate different aspects from serious accidents and potential risks.
Several of the speakers will address highly controversial political issues.
Nuclear risks is a matter of fear in large populations. It is extremely difficult to predict how dangerous the situation really is. Knowledge is an important basis for combating this fear. When we know, we can also act and prevent. Unfortunately some of those who have the highest political power are not always the most interested to take part in this knowledge, or they are not so interested to let the correct information become available, which is quite serious.
We are therefore looking forward to hearing presentations from some of those who really know.
From right: Professor Brit Salbu, Dr Deniz Yüksil-Beten, professor Ole D Lærum, Dr Elizabeth Atherton
Session 1, International Perspectives, chair professor Brit Salbu
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Britt Salbu |
Donald Malcom |
Mikhail Balonov |
Deniz Yuksen-Betel |
Nuclear Events in the Past
Malcom Crick, Secretary to UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) www.unscear.org
The health effects of exposure to radiation increases sharply above a dose of 1 Sv, giving visible burns, radiation sickness and eventually death.
Exposure between 1000 mSv and 100 mS gives increasing risks of cancer, observable in disease statistics.
For exposure of less than 100 mSv health effects are plausible, but below the statistical limit of epidemiology.
The average annual doses from natural background radiation is 1 to 5 mSv.
The nuclear bombs at Hiroshima and Nagasaki gave more than 100 000 immediate deaths. The surviving 86 500 is a primary source of information on radiation risks, showing 440 cases of cancer above the population average by 1999.
Atmospheric nuclear testing from 1952 to 1962 was the largest man-made release of radioactive materials to the environment, giving a total of 32 mill man Sv. (collective dose to the population)
Chernobyl, the worst accident in civil nuclear activity released 0.6 mill man Sv
The highest world average doses from atmospheric tests, occurred in 1963.
Individuals living near to the test sites may have received high exposure.
AMAP (Arctic Monitoring and Assessment Program) found a sharp peak in the radioactivity of reindeer meat and in the body of reindeer herders (4500 Bq/kg) in 1965 and a smaller peak in 1986 as effect of the Chernobyl accident.
Evaluating risks from exposure to radiation sources, one must not forget medical applications, said mr Crick. In 1985 a teletherapy unit containing 93 g of CsCl was accidentally opened and the CsCl powder was released in a Brazilian city. 112 800 individuals were surveyed and 271 persons found contaminated. There were four fatalities, eight with ARS (Acute Radiation Syndrome) giving a total of 70 with observable injuries.
Mr Crick expressed concern about the rapid increase in radiography and computer tomography. Damage and fatalities caused by radiotherapy is under-reported, said Mr Crick, summing up as follows.:
Atmospheric nuclear weapon testing was by far the largest man-made contributor to collective dose
Chernobyl was by far the worst nuclear accident.
Number of criticality accidents seems to have diminished with time
Number of accidents involving orphan sources is prominent
Civilian transport has never lead to radiation injury
Medical accidents are significant, and probably underreported and becoming more frequent
Consequences of the Chernobyl Accident based on Chernobyl Forum
Professor Mikhail Balonov. Institute of Radiation Hygiene, St. Petersburg, scientific secretary to the Chernobyl Forum and consultant for UNSCEAR.
Professor Balov gave a comprehensive resume of the Chernobyl accident and the efforts to reduce the damage to people, fauna and flora. Consequences of the accident has been assessed by a number of international bodies, last by the Chernobyl Forum 2003 – 2005. The Forums main conclusions are:
The accident at the Chernobyl NPP in 1986 was the most severe in the history of the world nuclear industry
Due to the vast release of radionuclides it became the first magnitude radiological accident that required substantial countermeasures i Europa.
However, in the course of years the most significant problems have become the social and economic depression of the affected Belarusian, Russian and Ukrainian regions and the associated serious psychological problems of the general pubic and emergency workers
The majority of the 600 000 emergency workers and the 5 million residents received only minor radiation doses, comparable with natural background levels. This is also the case for other European countries. – This level of exposure did not result in any observable radiation-induced health effects.
An exception is a cohort of early emergency workers who received up to 20 gray (Gy)
two persons killed
134 with ARS (Acute Radiation Sickness) 37 of these died by 2004
A cohort of children and adolescents in Belarus, Russia and Ukraine were given milk contaminated with radioiodine. 6000 developed thyroid cancer. More than 99% successfully treated, but 15 dead by 2004.
Doubling of leukaemia morbidity in workers exposed to more than 150 mGy, 5% increase in solid cancer and cardiovascular diseases and some increases in cataracts.
For the residents of the contaminated areas there are no reliable data on increase in any somatic diseases, except for thyroid cancer as reported above.
According to biostatistical forecasts, detectable increase in radiaction-induced morbidity is unlikely.
Radiation levels are reduced by a factor of several hundreds, therefore the majority of contaminated land is safe for life and economic activities.
The Exclusion Zone and some other limited areas should be retained for decades to come
Particularly high 137Cs activity is found in mushrooms, berries, game, reindeer and fish in “isolated lakes” These levels have persisted for two decades and is expected to continue for several decades.
Government countermeasures were on the whole timely and adequate. Now, however, social and economic restoration must be a priority.
Nuclear Risks, Safety and Security
Dr. Deniz Yüksel-Beten, Head, Threats & Challenges Section, Science Peace Program, NATO
Presentation of the new NATO SPS Committee & Program:
The main objective is to establish civilian cooperation between NATO countries and Partner and MD (Mediterranean Dialogue)countries and thereby contribute to solving problems to stability and peace. Participation by 56 countries: 26 NATO countries, 26 Partner countries and 7 MD-countries:
Session 2 Nordic Perspectives, Chair: Kjell Bendiksen
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Kjell Bendixen |
Elizabeth Atherton |
Lars-Otto Reiersen |
Britt Salbu |
Ole Harbitz |
Sverre Lodgaard |
Long-term Radioactive Wast Management in the UK
Dr. Elizabeth Atherton, Nuclear Decommissioning Authority, NDA
The NDA is a non-departmental Public body, established in April 2005 with the following objective:
To deliver safe, sustainable and publicly acceptable solutions to the challenge of nuclear clean-up and waste management.
The UK has been producing nuclear waste for more then 50 years. We are dealing with it now, not leaving it to future generations, said Dr Atherton. The Government is responsible for waste management policy and site selection.
Planning and developing geological disposal is based on partnership with host community, implementation by the NDA, strong independent regulation and independent scrutiny.
Radioactive Contamination in the Arctic.
Secretry General Lars-Otto Reiersen, AMAP, Arctic Monotoring and Assessment Program
AMAP is one of six bodies under the Arctic Council, with a geographic coverage extending to south of the Polar Circle, monitoring :
by taking samples from air, water, snow, ice & sediments, plankton, invertebrates & fish, mammals & birds and humans.
Three major sources contribute to widespread radioactive contamination of the Arctic:
Nuclear Risks in the Arctic
Professor Brit Salbu, Norwegian University of Life Sciences (UMB)
Site specific risks can be calculated for well known installations, while the probability of unforeseen events will depend on who will do the harm: Is Scandinavia a Terrorist target?
Overview of nuclear sources in Europe which potentially can effect the Arctic: nuclear weapons, nuclear power reactors, reactor driven submarines, civilian reactor-powered icebreakers, Concentrations of spent fuel and radioactive wastes i Andreeva Bay and Gremikha.
Evaluation of threat categories.
Conclusion: The treat is real, are we sufficiently prepared?
However according to James Lovelock: Nuclear Power is our only hope if we are to save the world – and the Arctic - from global warming.
Emergency Preparedness – Handling future nuclear events.
General director Ole Harbitz, Norwegian Radiation Protection Authority
Lessons learned from major releases of radioactive fallout:
Overview of main concerns: nuclear weapons, reprocessing plants, nuclear power plants, naval installations, accidents, dumping sites, visiting harbours, transport routes for spent nuclear fuel, dirty bombs.
Basis for threat assessment, probabilities and consequences.
Presentation of the Nuclear Emergency Preparedness Organisation - Royal Decree of 17 February 2006 - the Crisis Committee, mandate and actions during an acute phase.
Presentation of Radnett, Automatic Measurement Network and other monitoring systems.
Need for international cooperation, exercises and real life experience
Security aspects influencing nuclear risks in the Arctic.
Special advisor Sverre Lodgaard, Norwegian Institute of International Affairs
In the High North, the probability of the military postures causing nuclear damage is highest with respect to accidents at sea, with nuclear propulsion systems more than with nuclear weapons. The probability of terrorist theft of nuclear weapons and materials is lower. Actual use of nuclear weapons can never be excluded, but seems very unlikely. The consequences – the seriousness of the damage inflicted - are inversely related to the probabilities.
Plenary meeting at Gamle festsal, Oslo University, Chair Sverre Lodgaard
Risks from Nuclear sources in the 21 Century
Dr Hans Blix, former director of IAEA and chairman the WMD commission
Lecture as presented.
The world will ask for more energy. If nuclear energy is not used, other sources will be relied on. The various risks that we link to any use use of nuclear power should therefore be compared to the risks that would be incurred by the use of alternative sources: economy, assurance of fuel supply, safety in operation, safety in waste disposal and security.
Uranium fuel is inexpensive and the largest mined sources are in stable countries: Australia and Canada. The prices for reactor fuel have increased, but the influence on generating cost is much less than the effect of rising gas and oil prices on fossil fuel power plants.
It has been said that the supply of uranium will only last for 50 years. However only a small part of the energy content in the fuel rods is used in most countries. Some 80 to 100 times more energy can be extracted, at a higher cost.
Much focus is on safe storage of radioactive waste. All waste from nuclear power-plants is collected, concentrated and confined in safe, underground repositories. The waste from fossil fuel plants is diluted and dispersed into the atmosphere. The result is global warming.
The spent nuclear fuel may be retrieved and used for fuel in future nuclear reactors. A wise president of a Swedish commission om waste once said: Waste is what remains when our imagination has run out.
The nuclear accident at Chernobyl happened 20 years ago. Since then we have had no serious accident in civilian nuclear power. It was of a rare type of reactor that lacked containment. Most of the worlds light-water reactors have containment that stops any emissions of radioactivity into the environment.
The most severe accidents are in hydropower. When big dams have burst – which has has happened not so rarely – huge quantities of water has flooded downstream villages and towns with horrendous losses in life.
There is much worry about proliferation, but will a doubling of nuclear power plants in Sweden or in the US increase the risk? Sweden, Finland and Germany have had nuclear power for many years, but have refrained for nuclear weapons. Israel has nuclear weapons but no nuclear power.
We live in a world of some 27 000 nuclear weapons and 9 nuclear weapon states. The genie is out of the bottle. We can not uninvent the atomic bomb, but we can outlaw it. Proliferation is a question of political decisions and of the examples set by the US and Russia.
The window that opened at the end of the Cold War has been allowed to hang flapping in the wind, said Dr Blix. It is high time that it be fully opened and lead to a cooperative security order which eliminates the risk posed by nuclear weapons.
The lecture was attended by HKH Dronning Sonja and ambassadors from seveal countries
Dinner at The Norwegian Academy of Science and Letters on Thursday 20 September 2007
After dinner speech by Hans Blix. Speeches by Brit Salbu, Sissel Rogne and Odd Dørum
Celebration reetings from Kungliga Vetenskapaksademin og Ingeniørvetenskapsakademin and many others
Day Two
Opening words by professor Sissel Rogne, President of the Norwegian Polytechnic Society.
Session 3 International Perspectives on Nuclear Energy, Chair: professor Jan S. Vaagen
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Jan S. Vaagen |
Liv Monica Stubholt |
Kjell Bendiksen |
Rainer Salomaa |
Sunil Fleix |
Yachine Kadi |
Egil Lillestøl |
Introduction by State secretary Liv Monica Stubholt, Ministry of Foreign Affairs (as of 21 September 2007, 1200 hours: State secretary, Ministry of Oil end Energy)
Ms Stubholt commented on the Norwegian Governments official position along the following headlines
There may be a renaissance for nuclear power in conceptual terms, but any great expansion of nuclear power is still far off, said Ms Stubholt.
Norway fully supports the right to peaceful use of nuclear power.
In Norway, large-scale efforts will be made over the next decades to curb CO2 emissions, but reverting to a nuclear energy is, luckily I must say, not one of the options nearest at hand here.
Future Energy Supply – Nuclear Power in a Climate Perspective.
Managing director
Kjell Bendiksen, IFE, Institute for Energy Technology, Norway.
Fossile fuels cover 80%+ of the present global energy demand, and their share increases. Renewable energy amounts to less than 10% and is mainly hydropower, amounting to 89% of the total for renewables, with bioenergy at 7% in second place. Wind and solar contributes each 2% of the renewable energy.
This picture will not change much by 2030, said Bendixen. Fossil fuels will still dominate. The contribution from renewables will barely upheld its share, but wind power will increase. Hydro will however still be at 69% and wind at 15% of the total for renewables.
Contribution from nuclear power is about the same as from renewables. Nuclear´s share of electricity production in 2005 is 16%. This may increase to 18% in 2030, equivalent to a doubling in production capacity.
Ordinary spent reactor fuel must be stored for 250 000 years before the radiation level is reduced to that of natural uranium ore. Removing plutonium reduces the the time to 15 000 years. Removing the minor actinides further reduces necessary storage time to 250 years.
Nuclear energy have definitely become safer, said Bendiksen. A new Chernobyl accident is near impossible, but existing plants and old designs are not fool-proof.
Nuclear energy is the only available large scale power source with negligible GHG on the market.
Equipping existing fossil-fuel fired power-plants with capture and storage-systems means deploying 2 – 4000 CCS plants and safely to take care of 15 to 20 gigatons of CO2 annually before 2050.
GHG-emissions from nuclear plants are close to zero.
Power availability for nuclear plants has risen from 74% to 84%. New technologies may reduce the waste storage problem and at the same time extend fuel supply to thousands of years.
Public acceptance remains crucial.
Nuclear Energy –
The Finnish Solution and Position
Professor Rainer Salomaa, Helsinki University of Technology.
Finland has four nuclear power-plants providing 18% of the total fuel consumption. The total electricity consumption in 2005 was 85 TWh of which 20% was import, 16% hydro-power and 26% nuclear. From 1995 to 2003 the electricity consumption has increased by 22%, while the production capacity only has grown 15%.
The Finnish economy depends om the power consuming export industry, and its competitiveness depends on low and stable energy prices.
A comparison of electricity generation costs, with emission trading, shows that a nuclear power plant with 8000 operating hours/year gives lower prices than both Elspot, wind, gas, coal, peat and wood. Furthermore choosing nuclear enables Finland to meet its Kyoto commitments
The public acceptance for nuclear power in Finland has increased from 24% in 1982 to 50% in 2006, while the negative fraction is reduced from 38% to 20%.
Building of the 5th reactor, Olkiluoto 3, started in 2004 and it is expected to go in commercial operation after 2011. Planning and construction will give a total of 30 000 man-years, a peak workforce at the site of 2500, and engage 1600 subcontractors in 28 countries.
The spent fuel from Finlands five NPP´s will be stored in an underground, bedrock repository at Posiva. Construction started in 2005 with local consent.
Public opinion in Finland is pro nuclear power. A poll in 2006 showed 63% in favor and 33% against. Environmental Impact Assessments for a 6th NPP are under way for several locations in Finland.
Professor Salomaa emphasized that nuclear power means long-time commitment. The life-time for a modern NPP is 60 years and the plans for operation of the repository at Posiva extends to year 2140.
Fourth
Generation Nuclear Power Plants
By Jaques Bouchard, Charman of the Generation IV International forum (GIF)
Presented by Sunil Felix, Assistant to Jaques Bouchard
The Generation IV International Forum, GIF, was chartered in July 2001 to lead the collaborative efforts of the rld's future energy needs. www.gen-4.org/
By the end of 2002, the work resulted in a description of the six most promising systems and their associated R&D needs. The six systems feature increased safety, improved economics for electricity production and new products such as hydrogen for transportation applications, reduced nuclear wastes for disposal, and increased proliferation resistance.
Gen IV reactors can be made with closed fuel cycle where plutonium and actinides are consumed, reducing the volume and necessary storage time for spent fuel, and at the same time give a 70 to 100 times better utilization of the energy content in the fuel, compared to the once-through fuel cycle used today.
Gen IV gas cooled reactors can produce hydrogen by a thermochemical process, bypassing generation of electricity and electrolysis and they are suited for desalination of seawater.
Gen IV reactors should reach maturity by 2030, said Mr Felix
From
waste to value – Accelerator-based Inherently Safe Nuclear Power
Dr Yachine Kadi, Nuclear Scientist, CERN
A major innovation is needed to replace the expected “decay” of traditional energy sources.
Nuclear energy has the potential to satisfy the demand, at least 15 centuries for fission and infinite for fusion.
Can nuclear fission be exploited in a way that reduces the risk for accidents and eliminates proliferation of plutonium?
The idea of a accelerator-driven, sub-critical reactor had been around for a long time, said Dr Kadi.
Such reactors accept fuels that are not acceptable in critical reactors, such as minor actinides and high Pu-content and give much greater operational safety margins
The main objective is to reduce the production of nuclear waste. Fast neutrons allow a more efficient use by allowing an extended burnup. The strategy is to use the hardest possible neutron flux, so that actinides can fission instead of accumulating as waste. The radiotoxity of spent fuel reaches the level of coal ashes in 500 years, similar to what is predicted for future, hypothetical fusion systems.
When and where will the demo-plant be built?
Thorium
as an alternative fuel.
Professor Egil Lillestøl, CERN & University of Bergen
The world number one problem is the increasing global energy consumtion, growing at more than 3% per year, corresponding to a doubling in 20 years. Only massive use of nuclear power, combined with rapid development of direct conversion of solar heat may alleviate the problem.
Thorium is not fissile but fertile and can be transmuted to 233U which is fissile. This can be done in conventional nuclear power plants.
Thorium is much more abundant than the uranium and the thorium ore does not require the separation process necessary to enrich uranium.
Thorium has been tested for 40 years in nuclear reactors, with large efforts in India since 1995.
The road to commercialization of critical reactors based on the Th - 233U-cycle is long and costly.
However the Thorium-cycle for an accelerator-driven reactor is much simpler and could be developed fast.
Norway should build a pilot project, using existing technologies, with thorium from India, accelerator from Switzerland, reactor core from Russia and fuel processing for the US.
Session 4 Norwegian Perspectives of Nuclear Energy, Chair Reidun Sirevåg
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Reidun Sirevåg |
Arne Bjørlykke |
Per Strand |
Svein Sundsbø |
Waclaw Gudowski |
The occurrence of Thorium Minerals in Norway
Professor Arne Bjørlykke, Norwegian Geological Survey, NGU
Results from air-surveys show that that the Fens area in Norway may have large reserves of thorium.
USGS estimates that Australia may have 300 000 tons reserves, India 290 000 tons and Norway 170 000 tons, with a a world total of 1200 000 tons
Professor Bjørlykke pointed out that thorium from beach sand with monazites probably will be the main resource of thorium for many decades, because it is :
Easy and cheap to mine.
Easy to make a mineral concentrate.
There is an simple process of desolving monazite in sulphuric acid and precipitate Th-oxide.
Thorium in Norway is found in bed-rock. Professor Bjørlykke concluded:
Radiation Protection Aspects
Director Per Strand, Norwegian Radiation Protection Authority (NRPA)
Mr Strand presented an overview of radiation protection aspects throughout the the fuel cycle, international commitments and recommendations and Norwegian laws and regulations.
If Norway were to develop nuclear power, an extensive legislative work would need proper attention
IAEA safety standards would be useful resources in this work process.
Possible Industrialization of Norwegian Thorium Resources
Director Svein Sundsbø, Federation of Norwegian Industries.
The industry consumes about 40% of the total electrical energy used in Norway. There is an increasing lack of generating power in Norway, and the power balance for the Nordic countries is negative. This basic problem must be solved by installing new generation capacity.
The prices for electric power offered to the industry are no longer competitive. We have a dysfunctional energy market. Prices for oil and gas show large variations. The emission trading system reduces competitiveness with counties outside of the trading system. Dependence on energy from Russia gives uncertainty.
Will industry manage to reduce its dependence on fossil based energy, while at the same time uphold its competitiveness relative to third countries not subject to obligations to mitigate their carbon footprint?
New renewable energy is a positive asset, but will not solve the fundamental challenges because of insufficient and unstable production, to costly without subsidies, environmentally controversial.
Carbon capture and sequestration will be necessary for fossil based power, but it is a costly solution.
Nuclear power based on thorium is CO2-free. What about cost, environmental consequences and political accept?
Sundsbø concluded as follows
Norwegian Industries foresee two possible solutions:
Nuclear
energy – regional Needs, Problems and Solutions
Professor Waclaw Gudowski, University of Uppsala, Chairman of the Energy Committee in the Royal Swedish Academy of Science, Deputy Executive Director ISTC ( http://www.istc.ru/)
Professor Gudowski presented an overview of the vocabulary used to describe the processes in a nuclear reactor and its waste products, as well at the material flow in once-trough and closed-cycle reactors.
1.The regional energy consumption pattern differs, with Asia and Pacific heavily dependent on coal, South&Central America with a large share of hydropower. Nuclear power gives an important contribution only in Europe an the US
2.The world carbon emissions are growing quickly, although the carbon intensity is falling
Comparison of cumulated CO2-emissions from different means of electricity production puts hydro-electricity at the top with 4 g/kWh and nuclear as number two with 6 g/kWh. Coal is at the bottom with 978 g/kWh. Photovoltaic emits 60 – 150 g/kWh, reflecting the energy use for making the systems.
A comparison of land use land use for a 1000 MWe power-plant show that a nuclear power-plant only requires 1 – 4 km2, while biomass would require 4000 – 6000 km2
Is nuclear energy the solution? Yes, said professor Godowski. Advanced nuclear cycle adopted regionally, mitigates most of the problems. It is important with a regional nuclear fuel cycle, involving regional actinide management and regional approach to nuclear waste repository.
Closed nuclear fuel-cycle and possibly Th-based fuel cycle solves the problems of sustainability.
Regional approach can optimize costs of nuclear fuel cycle trough common politics and solutions in the front end and the back end of the fuel cycle.
Think globally – Act regionally:
A Nordic thorium initiative can be a perfect beginning.
The summing up
From left: Egil Lillestøl, NN?, Waclaw Gudowski, Rainer Salomaa, Arne Bjørlykke, Jon Samseth
Main topic in the final panel: The seponsiblilty to communicate from the scientitific society to society at large.
How can DNVA contribute to an informed debate on energy, climate, environment and proliferation of nuclear weapons?
By information!
Bilder: Nils Chr. Tømmeraas.
Referent: Nils Chr. Tømmeraas
