ГОДИШНИК НА МИННО-ГЕОЛОЖКИЯ УНИВЕРСИТЕТ “СВ. ИВАН РИЛСКИ”, Том 57, Св. II, Добив и преработка на минерални суровини, 2014 ANNUAL OF THE UNIVERSITY OF MINING AND GEOLOGY “ST. IVAN RILSKI”, Vol. 57, Part ІI, Mining and Mineral processing, 2014 RISK MANAGEMENT OF DISASTROUS EVENTS ON FLOTATION TAILINGS IN "RTB BOR" SERBIA Nenad Živković 1, Emina Mihajlović 2, Ljiljana Živković 3, Aca Božilov 4 1 University of Niš, Faculty of Occupational Safety of Niš, 18000 Niš, Čarnojevića 10a, nenad.zivkovic @znrfak.ni.ac.rs of Niš, Faculty of Occupational Safety of Niš, 18000 Niš, Čarnojevića 10a, emina.mihajlovic @znrfak.ni.ac.rs 3University of Niš, Faculty of Occupational Safety of Niš, 18000 Niš, Čarnojevića 10a, ljiljana.zivkovic @znrfak.ni.ac.rs 4University of Niš, Faculty of Occupational Safety of Niš, 18000 Niš, Čarnojevića 10a, aca.bozilov @znrfak.ni.ac.rs 2 University ABSTRACT. Flotation tailing dams are necessary mining facility from technological point of view, whereas in terms of environmental protection they are a real threat to humans and the environment, regardless of whether they are operational or the process of disposal has been completed. In southeastern Serbia, on the territory of Bor municipality, there are two active flotation tailings: Flotation Tailing RTH and Flotation Tailing Veliki Krivelj, which represent a potential threat of accidents. Occurrence of accidents should be the subject of research with the aim to recognize the mechanism of their generation, range and scope of environmental threat and risk assessment, in order to initiate the demands for the design and installation of safety systems with reliability that is higher than the total probability of danger. This article presents a risk management system in emergency situations in Flotation Tailing RTH and Flotation Tailing Veliki Krivelj which are part of the company "RTB Bor". The organizational structure of the risk management system in emergency situations has been based on the model of an integrated protection and rescue system in emergency situations. The aim of this paper is to answer the question whether the development of safety in emergency situations in Flotation Tailing RTH and Flotation Tailing Veliki Krivelj created conditions for the construction of a disaster resistant system. УПРАВЛЕНИЕ НА РИСКА ОТ СЪБИТИЯ С КАТАСТРОФАЛНИ ПОСЛЕДИЦИ ВЪВ ФЛОТАЦИОННИТЕ ХВОСТОХРАНИЛИЩА В “РТБ БОР“ СЪРБИЯ Ненад Живкович 1, Емина Михайлович 2, Лиляна Живкович 3, Аца Божилов 4 1 Университет в Ниш, Факултет по безопасност на труда, 18000 Ниш, Чарнојевића 10a, nenad.zivkovic @znrfak.ni.ac.rs 2 Университет в Ниш, Факултет по безопасност на труда, 18000 Ниш, Чарнојевића 10a, emina.mihajlovic @znrfak.ni.ac.rs 3 Университет в Ниш, Факултет по безопасност на труда, 18000 Ниш, Чарнојевића 10a, ljiljana.zivkovic @znrfak.ni.ac.rs 4 Университет в Ниш, Факултет по безопасност на труда, 18000 Ниш, Чарнојевића 10a, aca.bozilov @znrfak.ni.ac.rs РЕЗЮМЕ. Флотационните хвостохранилища от аспект на технологията представяват необходим минен обект, а от гледна точка на околната среда те са реална опасност за хората и околната среда, независимо от това дали са активни или пък процесът на съхраняване е завършен. В югоисточна Сърбия, в околността на община Бор, съществуват две активни флотационни хвостохранилища: ФХ „РТХ“ и ФХ „Велики Кривел“, които представляват потенциална опасност от аварии. Възникванията на аварии заслужават да бъдат предмет на изследване с цел да се определи механизма на тяхното образуване, обема и обхвата на застрашаването на околната среда и да се направи оценка на риска, за да се инициират изискванията за проектиране и изграждане на защитни системи, чиято надеждност трябва да бъде по-голяма от общата вероятност от опасност. В тази статия е представена системата за управление на риска в извънредни ситуации във ФХ „РТХ“ и ФХ „Велики Кривел“, които са част от компанията „РТБ“ Бор. Организационната структура на системата за управление на риска при извънредни ситуации е базирана върху модела на интегрирана защитна система и спасяване и управление на извънредни ситуации. Целта на статията е да се даде отговор на въпроса дали в „РТБ“ Бор, с развитието на концепцията на защита от катастрофи във ФХ „РТХ“ и ФХ „Велики Кривель“, са създадени условия за изграждане на система, която да е устойчива на катастрофи. of water, soil, plants, destruction of animal habitats, tailing flows down the residential houses due to the release of flotation sludge and its effluence in the form of slurry waves in the downstream areas. Dangerous occurrences can lead to sudden slides and faults in the drainage system and overflow points on flotation storages, cracks on the collector due to the pressures of sedimentary flotation, decay of the collector lining due to acid environment and destabilization of the entire flotation system.. Introduction Flotation tailings dams are natural or artificially reconstructed spaces for the accumulation of slurry (ground material and chemically contaminated water). Tailings dams are used for: tailings deposition, complete clarification of water, and the accumulation of effluents required in the flotation process. Safety of tailings dams refers not only to mining and construction, but also to the safety of people living downstream from tailing dams and the environment (Carlos and de Leon, 2006). Flotation tailings "Veliki Krivelj" owned by the company RTB Bor was built for the disposal of tailings from ore processing in the plant for copper ore flotation. It was formed in the valley of the Krivelj river and it consists of three dams constructed from cycloned sand. It consists of two ponds with a total area of about 226 ha, of which the field no. 1 occupies about 81 ha, Tailings dams accidents occur due to the simultaneous occurrence of hazardous conditions caused by natural disasters, technical defects and combination of these two causes. They trigger the environmental risks such as pollution 64 and the field no. 2 about 145 ha (Figure 1). About 190-195 Mt of tailings have been deposited here. For the purpose of OTICANJA the Krivelj River, the tunnel and the sewer were built beneath the tailings dams. Before the dam was constructed, it was necessary to build the tunnel, 1414 m long, and the collector, 2075 m long, both 3 m in diameter. During the exploitation, the there was a structural damage to the concrete lining of the collector which was primarily caused by unfavorable water chemistry and other negative influences. The Bor River was also cut by Bor pit and ancillary facilities around it, so that this water stream was also converted to the Krivelj river by the tunnel, 2250 m long and 1.8 m in diameter. The flow of the Bor River into the Krivelj river was located just upstream of the intake structure in the tunnel axis of the river. The tunnel \ sewer under the flotation tailings "Kriveljska reka" carried waters of both the Krivelj River and the Bor River. So far, the overhaul of the sewer under the flotation landfills included cementing the concrete ring inside the sewer pipes, so that the cross section was reduced from 3.0 m to 2.2 m. Therefore, it is also significant for future remedial actions on the tunnel and sewer, that there will be a reduction in sewer capacity under the flotation tailings (RTB Bor*, 2013). Downstream of the circuit of the Krivelj, the Bor and the Ravna River, until the ravine of Rgotsko, the width of the valley of the Bela River is 500 m. The average gradient of the bottom of the valley is 0.6%. Along the left bank of the river valley there are the railway line Bor - Zaječar and the road Donja Bela Reka. There are no major settlements at this area. At about 3 km downstream of the ravine, there is a village Rgotina through which the Bela Reka River flows. Downstream of the village Rgotina, the largest settlement is Vražogrnac and it is located about 1.5 km from the confluence of the Bela Reka River in the Timok River. Flotation tailing "RTH" is located about 500 m east of Bor (Figure 1). It contains about 50-60 Mt of tailings and covers an area of 86 h. Dams and peripheral embankment are constructed from cycloned sand. Definition of the disastrous event The greatest danger on flotation tailings, with disastrous consequences, is a potential dam breach and release of tailings. This is how large overflow wave that moves downstream of the tailings occurs (RTB Bor*, 2013). Tailings related disastrous events took place in many countries around the world: in the former Soviet Union, Chile (in 1967, when more than 200 people were killed); in the USA; in Germany (in Saxony in the 1960ies, 250 000 t of tailings flowed into the river; in Romania (Baia Mare on January 30th 2000, the Mura, the Tisa and the Danube River were poisoned with cyanides); in Macedonia (in a copper mine Bučim and lead and zinc mine Sasa in September 2003, the crater of 120-160 m appeared in the tailing dump at a depth of 30-40 m; over 1.000.000 tonnes of tailings spilled into the Kamenica river and lake Kalimanci, the Bragalnica river and the surrounding area (UNISDR, 2002)). The environment of the tailings is s as follows: Upstream the Krivelj valley along the dam no.1 there are no settlements except the mine facilities "Veliki Krivelj" and Flotation tailings "Veliki Krivelj", all the way to the village of Veiliki Krivelj. Veliki Krivelj village is located 4.4 km (in direct line). The width of the valley upstream of the tailings dam no. 1 is 300-400 m. The valley is covered with lush vegetation. Downstream of the dam no.3 in the flotation pond no. 2, there is the village of Oštrelj (about 1.5 km away), production facilities of the quarry (about 7.5 km away), and the village Rgotina about 11.8 km away. The valley of the Krivelj River downstream of the dam no.3 to the confluence of the Bor River and Ravna River is straightforward, with a width of 200-300 m. The average gradient of the bottom of the valley is 0.7%. Along the right bank of the valley there are local roads. The largest settlement in the area is Oštrelj. Disaster is a sudden accident or extreme calamitous event that causes great damage to the people and the environment. Disasters happen quickly, with great intensity of impact, randomly, not choosing the time, the place and the size of the consequences in the affected area, and to the extent to which local and regional resources cannot meet the needs of vulnerable people in terms of eliminating the consequences (USAID, 2008). They are the result of hazard, the vulnerability of the affected territory (casualties and disruption of normal activity) and a lack of ability or lack of adequate measures to reduce the potential risk. The analyses of disasters often only focus on risk and not on the community. It is important to realize that the disaster itself may be caused by social, political and economic environment. In most cases, the disaster is not individual and isolated occurrence. Every disaster is further complicated by human actions to mitigate the consequences. Risk largely depends on the social system and relations of power that affect different social groups. It is not enough just to know the types of risk in order to understand the disaster, but also a different level of vulnerability of different groups of people, which is best understood in the context of the political and economic systems that operate on a national and international level. Hazard can be defined as a dangerous condition or a dangerous event that poses a potential threat and can be harmful to people, property or the environment. Hazards can be classified into two categories: natural hazards and hazards caused by human activities. Natural hazards are those that are caused by natural phenomena (meteorological, geological or Fig 1. Layout view of the flotation tailings and environment (RTB Bor, 2013) 65 even biological origin). The examples of natural hazards are cyclones, earthquakes and volcanic eruptions that are exclusively of natural origin. Landslides, floods, droughts and fires are socio - natural hazards, since they are incurred by both natural and human activities. For example, floods can occur due to heavy rainfall, landslides or due to obstructions in the drainage systems caused by municipal waste. Hazards caused by human activities mainly occur due to human negligence. They are associated with industrial facilities and power plants, and they involve fire, explosion, release of hazardous waste, dam breach or burst, etc. Every disaster begins with a threat regardless of the fact it is known in advance or not. Any threat, whether it is a natural, technical or nuclear has the potential to cause serious adverse effects rooted in every unwanted event. Event itself is not a threat, hazard is threat; it is manifested in an actual harmful event and has specific scenarios by where it happens. uninhabited area cannot be considered a disaster, regardless of its size. The flood is considered a disaster only when it has a negative impact on humans, their activities and material assets (property). Therefore, a disaster occurs only when hazard and vulnerability encounter. It should also be noted that the risk decreases with increasing capabilities and preparedness of society and the environment to cope with the disaster. Therefore, we must consider three main components in accident management: hazard, vulnerability and disaster preparedness. Disaster preparedness and response capabilities are the strength (capacity) of a company, individual or community to cope with, or prepare for prevention, mitigation, or a quick recovery after the accident. Risk is a measure of the expected losses due to hazards that occurred in a given area during a specified time interval. The risk of hazard is the function of that specific hazard and losses that it could inflict. The degree of risk depends on: the nature of hazards, vulnerability of affected elements, and the economic value of these elements. Risk indicates the degree of possible losses in urban areas depending on their exposure to hazards and can be seen as the product of the probability of risk and vulnerability. Risk assessment of hazardous activities is a process, which determines the risk based on the assessment of the probability of an accident and the possible consequences on the life, health and the environment. Based on risk assessment, it can be concluded whether the risk of dangerous activities in a particular area is acceptable. It is believed that the acceptable risk is the one that can be controlled under certain conditions prescribed by the regulations. If the risk cannot be controlled under certain conditions, the risk can not be accepted. In order to determine the levels and dimensions of risk, it is necessary to define risk in terms of time and its stages, as precisely as possible. The risk involves the following stages (USAID, 2008): Identification of accident risk; Modeling the development of an accident and consequences; Vulnerability Analysis (qualitatively - the degree of strength, and quantitative ranking); The method of response (response to the accident); Post-accident monitoring; Measures to eliminate the consequences of the accident (recovery). These stages indicate what can be done and what is necessary to be done to avoid the accident. Vulnerability can be defined as the degree to which a particular society, system, service or geographic area may withstand a specific hazard on account of its nature and characteristics, as well as the distance from hazard-prone areas. Vulnerability is defined as “the exposure to the cases, stress and difficulties that a community is affected by”. Chambers discusses the external and internal side of vulnerability. The exterior side is related to external shocks and stresses and internal side is associated with defenselessness, incapacity to cope without damaging losses. Different views on the vulnerability reveal that the term has been used in many different contexts by many different authors, such as property of an element, a system or a community to be influenced upon or to be subject to damage, or the impact of unforeseen events and stress on the communities. In the context of risk, vulnerability is defined as an internal risk factor, opposite to danger which is defined as an external risk factor. According to Cardona (USAID, 2008) vulnerability is the result of three factors: Physical fragility or exposure, linked to the susceptibility of human settlements to be affected by natural or social phenomena due to their location in hazard-prone areas; Socio-economic fragility, linked with the predisposition to suffer harm due to marginalization, social segregation in human settlements, and due to poverty and similar factors; and. Lack of resilience, related to the limitations of access and mobilization of resources, and incapacity to respond when it comes to absorbing the impact of a disaster. It may be associated with underdevelopment and the lack of risk management strategy. Accidental risk management cycle Accidental risk management cycle (Figure 2) implies the sum of all activities, measures and programmes to be taken before, during and after the accident in order to avoid accidents, reduce its impact and recover from the damage incurred. There are three key stages in the management of accidental risks: Vulnerability is characterized by the following factors: coping capacity, robustness, resilience, exposure, sensitivity or susceptibility. General characteristic of vulnerability is the fact that the degree of vulnerability of infrastructure, community, society, or process is associated with the size of a given hazard. For example, in the case of earthquakes, majority of the buildings is not vulnerable to tremors, while the majority of buildings are vulnerable to strong earthquake. In that case, this dependence of vulnerability could be explained by the strength of hypothetical events. Each hazard is so-called trigger event, which in combination with high levels of vulnerability (inaccessibility, old and sick people, lack of awareness and information, etc.) leads to disaster and the human and material losses. For example, in case of tailings dams breach in an 1. Pre-accident stage: The activities undertaken in this phase are aimed at reducing the potential financial loss in the case of an accident. They can include for example, early warning campaigns, strengthening the existing weak structures, preparing plans for risk management in the households and community, etc. The actions taken at this stage are called preparedness and mitigation measures. Preparedness - prevention includes protection and 66 precautionary measures to prevent the effects of the disaster. This includes political and legislative measures related to urban planning, that are not harmful to human well-being and the ecosystem. In most cases, it is difficult to completely prevent the natural disaster, and therefore, the following two steps are very important. Mitigation reduces the risk of disaster. The examples of mitigation may be the division into zones, the appropriate land use, the objects with support in the coastal areas or retention of vegetation on muddy terrains that make firmer foundation, as well as education and consciousness awareness. Preparedness is a state that aims to reduce the casualties and damage to buildings and infrastructure through rapid and efficient actions. Properly implemented preparedness measures allow communities and institutions to respond to disastrous situations in a quick an organized way. Preparedness measures also include early warning systems, plans and evacuation routes, and similar. Accidental risk management on flotation tailings “RTB BOR” Accidental risk management cycle (Figure 2) implies the Risk management includes a set of management methods and techniques used to reduce the possibility of unwanted harmful events and consequences, and to increase the likelihood of achieving the intended results. As there is no single definition of risk, there is also no single definition of risk management. It is often defined as - a systematic process that includes identifying and measuring the risks at which the objects and the individuals are exposed to, as well as the selection and implementation of the most appropriate methods to manage these risks. The process of risk management is essentially a multidisciplinary process which embodies various disciplines and methods to solve risk related problems. In fact, it is a systematic process of identification, examination and evaluation of the possibility of damage in an organization or individual; also, it can be seen as a systematic process for selecting the best way to handle all the possible risks which is consistent with the goals of the an organization or an individual. The basic concept of risk management tends to shift the risk from the framework of uncertainties and unknowns in the framework of knowledge and probability. This process is facilitated by gathering, processing and storing information needed to understand the possible positive and negative aspects of all the factors that may affect the realization of an event. This process increases the likelihood of success, and reduces both the probability of failure, as well as uncertainty about achieving the overall goals of the organization. The stages in risk management are presented in Figure 3. Fig 2. Accidental risk management cycle (Khan et al., 2008) 2. The stage during the accident: It implies steps to be taken for more effective care for the victims and reducing the harm suffered. The actions taken at this stage are called measures of current response to the accident. 3. Post-accident phase: It involves initiative to respond to the accident with the aim to quicken the recover of the affected population immediately after the accident occurred. These activities are referred to as the measures of rapid - emergency response and recovery. This goal can be achieved only after the disaster took place. Response (immediate mitigation), the return to normal conditions and rebuilding now became the primary goal. Response (immediate mitigation) is a set of actions taken immediately after the disaster in order to reduce the number of human victims, provide assistance and mitigate suffering, as well as to reduce the economic loss. Some of the examples of this stage are the following: placing people in a safe location and providing assistance in terms of food, clothing and life essentials. Recovery (the return to normal state) includes the activities undertaken at this stage to ensure at least minimum human activities and the functioning of the important facilities, as well as setting the guidelines for normalization of the standard of living after the disaster. This includes the construction of temporary housing and achieving a certain standard of living. Reconstruction is a long-term response to the effects of the disaster. At this stage, the infrastructure, ecosystems and living conditions are being renewed. Fig 3. Risk Management Stages (Avdalovic et al., 2008) The risk of dam failure or breach on the flotation tailings RTB Bor arises from a number of circumstances: construction technology is such that new layers are fully or partially based on a relatively weak loadbearing layers from the previous cycle of filling, which reduces the overall stability of the structure; the dams are formed of a material without a clay core, so that the level of incoming water is rather high, and insufficient drainage may be the cause of the dam damage or failure; poorly sized or neglected derivative facilities can cause the dam breach during the intense rainfall; due to liquefaction, stronger earthquake would be devastating for the flotation tailing dams; 67 Propagation speed of the front wave is 3.6 m/s. After that, the speed of the front wave decreases and it is 2.2 m/s, so that it arrives in the village Rgotina in 73 min, and in Vražogrnac in 170 min. The width of the flood zone ranges from 200 d0 300 m all the way to the ravine of Rgotinsko, and then expands to reach 400 m near Rgotina, and 800 m near Vržognac. In settlements Rgotina and Vražornac all the dwellings are threatened. It is concluded that the maximum vulnerable zone in the worst scenario of dam breach in the case of “Veliki Krivelj" is 28 km. In the case of this scenario, the possible level of accident is level 4, which is the regional level (RTB Bor*, 2013). The measures for the recovery of the tailings dams "Veliki Krivelj" (RTB Bor*, 2013), under the control of RTB Bor and the Government of the Republic of Serbia, indicate that the likelihood of the occurrence of the worst scenario is considered as unlikely. The evaluation of consequence, in these conditions, ranges from significant to catastrophic. Therefore, the consequences are severe and the risk is medium. the downstream slopes of the dam are not protected against erosion; observation is not followed by the possibility of automated warning. The objectives of managing accidental risks – disasters on flotation tailings rtb bor are the following: to provide conducting activities within the limits of acceptable risk; to reduce or to avoid potential losses from hazards; to provide prompt and the appropriate assistance to victims of disasters; to achieve rapid and efficient recovery. Efficient risk management involves proper design, testing and evaluation of risk exposure. A number of methods have been developed for this aim and they are becoming more and more sophisticated. Qualitative methods of "risk matrix" (SER 2010) will be applied in this case, Figure 4 and 5. According to the defined scenarios, the simulation of two typical scenarios was performed in the case of flotation tailings RTH: Risk assessment of dam breach on the north side is the scenario no. 1, and risk assessment of the dam breach on the south side is the scenario no. 2 (RTB Bor, 2013). Slurry wave in the scenario no.1 covers the area of about 1 km, starting from the tailings and the pit of the old open pit mine. This area is characterized by a dump of retention capacity in the central part, while the parts immediately downstream the dam and upstream of the entrance to the old open pit are extremely steep. The time of from wave movement from the dam to the entrance to the open pit is about 4 min. The average speed of the waves is 17 km/h. The timing of the highest flow at the entrance to the old open pit is approximately 13 min. Such a short period severely limits the possibility of early warning and completely prevents timely measures to protect property in the affected area. In this area, there are no significant housing and infrastructure facilities, there are only industrial buildings of Mining and Smelting Plant Bor. However, water from the tailings pond (containing a certain amount of tailings) could end up in the pit of the old open pit mine, which would cause the adverse economic and environmental consequences. Calculations for Scenario 2 were done in 0 two cases: in the case of the wave of “clean"water and the wave containing a mixture of water and tailings. Slurry wave created by the dam failure on the western part of the tailings RTH would endanger the road and the railroad tracks right next to the tailings pond. According to the predicted scenario, the wave would end in a dump south of the tailings. Fig 4. Matrix of the consequence indicators Fig 5. Matrix of the risk assessment According to the Regulation on content of Policy for accident prevention and content and methodology for development of safety report and Accident prevention policy (Official Gazette of RS, No. 41/10), the analysis and modeling effects define the potential scope of the accident and the consequences for human life, health and the environment (SER 2010). Water pressure can cause the demolition of road-railway embankment which borders the above mentioned dump, road and railway cutoff and the runoff of water from the dump to the valley of the Bor river, where the village Slatina would be endangered. Bor River valley is approximately constant in width and it has a uniform longitudinal gradient. The level of vegetation spread (which affects the propagation of the wave) is moderate. The results of calculations for "clean" water and the mixture show differences only at a relatively short distance from the dam; downstream, these differences become less noticeable. To the entrance to the affected village Slatina, the largest flow is about 720 m3/s for the mixture, and about 550 m3/s for water, while at the exit of the village, in both cases, the largest flow is about 300 m3/s. In the village Slatina, the front wave arrives in about 6 min from dam failure, while the peak wave arrives 10 min. The front part of the wave is out of Following the above mentioned scenarios, we carried out the simulation of risk assessments in the case of breach of dam no.1, 2 and 3 in the flotation tailings "Veliki Krivelj". Risk assessment of the dam no.1 breach shows that the zone of vulnerability lies about 4 km upstream from the tailings dam no.1, without threatening the settlement Krivelj (RTB Bor*, 2013). Likelihood of this scenario is low, and the consequences range from insignificant to severe, and therefore this is insignificant risk. Assessment risk of breach in the dam no. 2 and no. 3 shows that the vulnerability area extends downstream of the tailings dam to the confluence of the White and the Timok River. The slurry wave ends up behind the village Vražogrnac. The front wave reaches the ravine of Rgotinsko, 10.3 km downstream from the dam in only 50 min. 68 the village of Slatina in 18 min, and the peak wave in 25 min. The flood wave reaches the confluence of the Bor and the Krivelj River in 36 min, and the peak wave in 47 min. The likelihood of accident in the worst case of dam breach scenario in flotation tailings "RTH" is unlikely. The assessment of consequences, in these cases, range from significant to catastrophic. Unlikelihood of the dam breach accident generates medium risk in the risk matrix. References Avdalovc. V., D. Cosic, S. Avdalovic. 2008. Risk management in insurance. Faculty of Technical Sciences, Novi Sad, 188 p. (in Serbian) Carlos, J., V. de Leon. 2006. Vulnerability. A Conceptual and Methodological Review, Source, 4/2006, UNU-EHS, Bonn, 64 p. Khan, H., L.G. Vasilescu, A. Khan. 2008. Disaster Management CYCLE – a theoretical approach, Management and Marketing Journal, 6, issue 1, 43-50. RTB Bor. 2013. Safety report for the fotation tailing “Bor” (in Serbian) RTB Bor*. 2013. Safety report for the fotation tailing “Veliki Krivelj” (in Serbian) SER 2010 Regulation on content of accident prevention policy and the content and methodology of Safety report and Accident protection plan. (in Serbian) http://www.merz.gov.rs/sites/default/files/Правилник%20о %20садржини%20политике%20превенције%20удеса.pdf UNISDR. 2002. Guidelines for reducing flood losses. United Nations. http://www.unisdr.org/files/558_7639.pdf USAID. 2008. Emergency management and vulnerability assessment on a local level. (in Serbian) Conclusion Knowing the risk of disastrous events on flotation tailings is necessary because it provides information that is needed to improve prevention and preparedness and to create effective early warning systems for disasters. Apart from hazard and vulnerability, it is very important to include another component in the accidental risk management process: the ability and preparedness of the system to cope with the disaster, in other words the strength of the society, individual or community to resist or prepare for the prevention, mitigation or a fast recovery after the accident. Risk assessment of the dam FJ RTB Bor breach presented in this paper, and carried out according to the methodology for the development of the Safety report and Accident prevention policy, where the modeling and analysis of their effects demonstrated the possible scope of the accident and consequences to the life and health of people and the environment, shows that the risk of hazardous activities in the analyzed area is acceptable and that it can be managed under certain conditions prescribed by the regulations. The article has been reviewed by prof. M. Michaylov. 69