Department of International Relations and European Studies1 Environmental Aspects of Nuclear Energy doc. PhDr. Tomáš Vlček, Ph.D. tomas.vlcek@mail.muni.cz Department of International Relations and European Studies2 Contents ̶ Environmental aspects assessment ̶ Environmental Impact Assessment ̶ Nuclear energy ̶ Production of fissile materials ̶ In Situ Leaching ̶ Radioactivity and Ionizing Radiation ̶ Radiation Exposure ̶ Protection against radiation ̶ Effects on human organism Department of International Relations and European Studies3 Environmental aspects assessment ̶ Over the next five minutes each of you write pros and cons of nuclear energy in terms of national energy security. Department of International Relations and European Studies4 Environmental aspects assessment ̶ Over the next five minutes each of you write pros and cons of nuclear energy in terms of purely subjective, personnal point of view. Department of International Relations and European Studies5 Environmental aspects assessment ̶ To bridge the conflict between state and industry interests and personal subjective perception of the problem serves the EIA. Department of International Relations and European Studies6 Environmental aspects assessment What is an environmental aspect ? According to ČSN EN ISO 14001 definition: „The environmental aspect is an element of the activities, products or services that can interact with the environment.“ Department of International Relations and European Studies7 Environmental aspects assessment ISO 14001 (voluntary norm of the International Organization for Standardization on environmental management, prestige of the company, the norm requires to have an environmental policy and environmental risk assessment) EMAS (Environmental management and audit system developed by EC in 1993, it requires ISO 14001 and other requirements such as the involvement of employees, etc., EMAS is thus perceived as a premium tool for environmental management. As part of this process so called Environmental review takes place - own risk identification, preparation of environmental policy, determining environmental aspects, objectives, programs) Department of International Relations and European Studies8 Environmental aspects register Department of International Relations and European Studies9 Environmental aspects register Department of International Relations and European Studies10 Environmental aspects assessment Methodology for assessing the environmental aspects Assessment of the EA is performed using following 4 criteria. Criteria: -compliance with the limits and mandatory requirements -frequency impact -impact associated with the effects on the environment (size, persistence, scale) -impact on society (its economy and image) Department of International Relations and European Studies11 Environmental aspects register Department of International Relations and European Studies12 Environmental aspects register Department of International Relations and European Studies13 Environmental aspects register Department of International Relations and European Studies14 Environmental Impact Assessment Directive 2011/92/EU on the assessment of the effects of certain public and private projects on the environment The EIA Directive of 1985 has been amended three times, in 1997, in 2003 and in 2009 Mandatory EIA: all projects listed in Annex I are considered as having significant effects on the environment and require an EIA Discretion of Member States (screening): for projects listed in Annex II, the national authorities have to decide whether an EIA is needed. This is done by the "screening procedure", which determines the effects of projects on the basis of thresholds/criteria or a case by case examination. However, the national authorities must take into account the criteria laid down in Annex III. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32014L0052 Department of International Relations and European Studies15 Environmental Impact Assessment Crude-oil refineries, gasification and liquefaction of 500 tonnes or more of coal or bituminous shale per day, Thermal power stations, Nuclear power stations, Installations for the reprocessing of irradiated nuclear fuel, fuel enrichment, processing, waste disposal, smelting of cast iron and steel, production of non-ferrous crude metals from ore, Installations for the extraction of asbestos and for the processing and transformation of asbestos and products containing asbestos, installations for the manufacture on an industrial scale of substances using chemical conversion processes, Construction of lines for long-distance railway traffic and of airports, motorways and express roads, new road of four or more lanes, or realignment and/or widening of an existing road of two lanes or less so as to provide four or more lanes, Inland waterways and ports for inland-waterway traffic, Waste disposal installations, Groundwater abstraction, Waste water treatment plants, Extraction of petroleum and natural gas, Dams and other installations designed for the holding back or permanent storage of water, Pipelines with a diameter of more than 800 mm and a length of more than 40 km, Installations for the intensive rearing of poultry or pigs with more than, Industrial plants for the production of pulp and paper, Quarries and open-cast mining, Construction of overhead electrical power lines with a voltage of 220 kV or more and a length of more than 15 km, Installations for storage of petroleum, petrochemical, or chemical products, Storage sites of carbon dioxide, Installations for the capture of CO2 Department of International Relations and European Studies16 Environmental Impact Assessment The process is: - announcement to the authorities (Region, ME) - official publication/announcement by the competent authorities - 20-day deadline for comments - screening procedure - documentation - preparing the report (90 days) - Comments (30 days) - the final opinion as a professional basis for related procedures (eg. land, construction) valid for 5 years and with the possibility of extension Department of International Relations and European Studies17 Department of International Relations and European Studies18 Nuclear energy in general - production of fissile materials (conventional mining, chemical treatment, in-situ leaching) - production of electricity in nuclear power plants - release of nuclear energy from the atomic nucleus - chain fission in nuclear fuel - accompanying phenomenon - ionizing radiation Department of International Relations and European Studies19 Production of fissile materials Mining in the open pit mines: ̶ extraction in open pit mines very similar to coal production ̶ generally the least impact on the environment with respect to other methods of mining ̶ extraction of nuclear fuel is just as harmful as other methods of mining ̶ intervention in the landscape depends on the amount of ore and yield (percentage of) nuclear fuel Department of International Relations and European Studies20 Production of fissile materials Department of International Relations and European Studies21 Production of fissile materials Chemical processing of mined ore ̶ Czech example: Mydlovary MAPE, 20 km from Temelín NPP ̶ leaching with sodium bicarbonate (higher content of carbonates) or sulfuric acid (reduced content of carbonates) ̶ ratio of sulfuric acid up to 560 g of 94% acid per one liter of the leached material ̶ processed 16.7 mil. tonnes of ore, formation of tailing ponds with a total area of 300 ha - 36 mil. tonnes of sludge ̶ heavy metals and radioactive substances Department of International Relations and European Studies22 Production of fissile materials Department of International Relations and European Studies23 Production of fissile materials Department of International Relations and European Studies24 Production of fissile materials Department of International Relations and European Studies25 Production of fissile materials Department of International Relations and European Studies26 Production of fissile materials Department of International Relations and European Studies27 Production of fissile materials - ISL In situ leaching (ISL), also known as solution mining, or in situ recovery (ISR) in North America, involves leaving the ore where it is in the ground, and recovering the minerals from it by dissolving them and pumping the pregnant solution to the surface where the minerals can be recovered. Consequently there is little surface disturbance and no tailings or waste rock generated. However, the orebody needs to be permeable to the liquids used, and located so that they do not contaminate groundwater away from the orebody. In the last five years, 48-51% of world uranium mined was from ISL operations. Most uranium mining in the USA, Kazakhstan and Uzbekistan is now by in situ leach methods, also known as in situ recovery (ISR). ISL mining of uranium is undertaken in Australia, China, and Russia as well. In USA ISL is seen as the most cost effective and environmentally acceptable method of mining, and other experience supports this. Department of International Relations and European Studies28 Production of fissile materials - ISL Department of International Relations and European Studies29 Production of fissile materials - ISL Department of International Relations and European Studies30 Production of fissile materials - ISL Department of International Relations and European Studies31 Production of fissile materials - ISL The advantages of this technology are: - the reduced hazards for the employees from accidents, dust, and radiation, - the low cost; - no need for large uranium mill tailings deposits. The disadvantages of the in-situ leaching technology are: - the risk of spreading of leaching liquid outside of the uranium deposit, involving subsequent groundwater contamination, - the unpredictable impact of the leaching liquid on the rock of the deposit, - the impossibility of restoring natural groundwater conditions after completion of the leaching operations. - Moreover, in-situ leaching releases considerable amounts of radon, and produces certain amounts of waste slurries and waste water during recovery of the uranium from the liquid. Department of International Relations and European Studies32 Production of fissile materials - ISL ̶ In the case of Königstein (Germany), a total of 100,000 tonnes of sulfuric acid was injected with the leaching liquid into the ore deposit. At present, 1.9 million m3 of leaching liquid are still locked in the pores of the rock leached so far. ̶ Groundwater impact is much larger at the Czech Republic‘s in-situ leaching site of Stráž pod Ralskem: 28.7 million m3 of contaminated liquid is contained in the leaching zone, covering an area of 5.74 km2. This zone contains a total of 1.5 million tonnes of sulphate, 37,500 tonnes of ammonium, and others. In addition to the chemicals needed for the leaching operation (including 3.7 million tonnes of sulfuric acid, among others), 100,000 tonnes of ammonium were injected; they were a waste product resulting from the recovery of uranium from the leaching liquid. Moreover, the contaminated liquid has spread out beyond the leaching zone horizontally and vertically, thus contaminating another area of 28 km2 and a further 235 million m3 of groundwater. ̶ In Bulgaria, a total of 2.5 million tonnes of sulfuric acid was injected into the ore deposits exploited by in-situ leaching. It is estimated that about 10% of the surface area used for ISL could be contaminated from solution spills. ̶ The Devladovo site in Ukraine was leached with sulfuric and nitric acid. The surface of the site was heavily contaminated from spills of leaching solutions. Groundwater contamination is spreading downstream from the site at a speed of 53 m/year. It has traveled a distance of 1.7 km already and will reach the village of Devladovo after 24.5 years. Department of International Relations and European Studies33 Radioactive decay ̶ radioactivity (or radioactive decay) is a spontaneous transformation of unstable nuclides or process by which an unstable atomic nucleus loses energy by emitting radiation ̶ new lighter elements emerge from the decay along with ionizing radiation ̶ natural radioactivity: natural transmutations, decay of nuclei by decay series and established principles ̶ artificial radioactivity: transmutation, chain reaction, particle acceleration (artificial radioactivity is induced by external force) Department of International Relations and European Studies34 Radioactive decay - types Department of International Relations and European Studies35 Radioactive decay – half life Department of International Relations and European Studies36 Radioactive decay – half life examples Department of International Relations and European Studies37 Radioactive decay – half life examples Department of International Relations and European Studies38 Radionuclides Cosmogenic radionuclides: tritium 3H (half-life 12,5 years), carbon 14C (half-life 5730 years) Primary radionuclides : potassium 40K (half-life 1,26x109 years), thorium 232Th (halflife 1,4x1010 years), uranium 238U (half-life 4,5x109 years), 235U (7x108 years) Secondary radionuclides: radionuclides of decay series – thorium, uranium, aktinouranium, neptunium Department of International Relations and European Studies39 Sources of human radiation exposure Department of International Relations and European Studies40 Department of International Relations and European Studies41 Radiation exposure Czech Republic - cca 3 mSv/year Iran (Ramsar) - up to 400 mSv/year India (Kerala) - up to 17 mSv/year Brazil (Guarapari beach) - up to 175 mSv/year Department of International Relations and European Studies42 Radioactive exposition Department of International Relations and European Studies43 Radiation exposure Sievert is a measure of the health effect of low levels of ionizing radiation on the human body Department of International Relations and European Studies44 Radioactive exposition Department of International Relations and European Studies45 Radioactive exposition Department of International Relations and European Studies46 Effects on human organism Department of International Relations and European Studies47 Effects on human organism Stochastic (random) - few cells damaged, subliminal dose or repeated small doses. - we can only calculate the probability of injury, no injury may in fact occur. - can be detected only by observing a large number of people. Risk of small doses? Scientists still do not match, they can not confirm nor deny it for there is not a sample of people who are not exposed to any radiation at all. No control sample. - It is known that there is a "protective effect" radiation (hormesis) - in places with higher radioactivity there is less incidence of cancer (cells repair any damage). Department of International Relations and European Studies48 Effects on human organism Non-stochastic effects (deterministic) - after a large dose of radiation, many cells, appear in a short time. Examples: local dermatitis Lenticular opacities birth defects fertility Acute radiation sickness Department of International Relations and European Studies49 Protection against radiation ̶ Distance - ionizing radiation intensity decreases with the square of the distance, ie. after 10 m it is 100 times lower, after 100 m it is 10000 times lower, after 1 km it is a million times lower. ̶ Time - the shorter the exposure, the smaller the cumulative dose ̶ Shielding - depending on the type of radiation: alpha radiation skin tones, clothing, paper; beta radiation, aluminum sheet; gamma rays concrete, a layer of water, soil; neutron radiation, water, polystyrene, paraffin. ̶ Diffusion and dilution – wind, rain etc. Department of International Relations and European Studies50 Protection against radiation Department of International Relations and European Studies51 Radiation vs. radiocontamination ̶ Radiation: subject or object directly exposed to ionizing radiation from a radioactive source; the subject or object does not become radioactive but is damaged by radiation. ̶ Radiocontamination: radioactive particles get in direct contact with organism. We distinguish between outer radiocontamination (dust and particles on the surface) and inner radiocontamination (dust and particles inhaled, consumed or penetrated through skin injuries). Department of International Relations and European Studies52 Protection against radiation Objective of the radiation protection To ensure that during normal operation the radiation exposure inside the device and/or the release of radioactive materials into the environment is as low as reasonably achievable, taking into consideration economic and social factors and prescribed limits and ensure mitigate the extent of exposure to radiation accidents. The principle of ALARA ̶ Observe the rules and seek new and better ways of performing work ̶ Already applied in the design Department of International Relations and European Studies53 Protection against radiation ̶ the use of nuclear energy is regulated by law ̶ nuclear safety is not a mere formality, it is an enforceable requirement ̶ all effects are monitored and evaluated ̶ responsibility is transferred to the operator's license holder Department of International Relations and European Studies54 Protection against radiation Deep protection = means to achieve the basic objective of safety First barrier: molecular matrix fuel (almost all the fission products resulting from fission are captured in the matrix of the uranium tablets) Second barrier: hermetic fuel cladding (an alloy of zirconium- niobium) Third barrier: the primary circuit pressure limit (resistant to high pressure, temperature, radiation and radiation dynamic conditions of operation) Fourth barrier: hermetic borders of rooms - containment (building design protection, resists airplane crash, blast wave, explosion, storm, extreme temperatures, extreme precipitation, etc.) Department of International Relations and European Studies55 Thank you for your attention.