Navegando por Assunto "Barragem"

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Acesso aberto (Open Access)
Análise do potencial de risco de rompimento em barragens de rejeito de mineração do Estado do Pará utilizando a metodologia Risk-Based Profiling System (RBPS).
(Universidade Federal do Pará, 2018-05-30) CONCEIÇÃO, Raimundo Almir Costa; LIMA, Aline Maria Meiguins de; http://lattes.cnpq.br/6572852379381594
The serious and very serious socioenvironmental disasters related to disruption in mining tailings dams have been exhibiting worldwide, a growing tendency since the 1960s and this is directly related to the increasing production of waste. In this context, there is a fundamental necessity for risk and safety analyzes of these dams, which can be done through methods that estimate the probability occurrence of disruption events, in order to make the decision to have a process more focused and safe. One of these analyzes is the so-called Risk-Based Profiling System (RPBS), which allows us to gauge, from qualitative data, the probability of a disruption and its probable consequences, which comes from the four most frequent scenarios (static, hydrological, seismic and operation and maintenance). This analysis was applied to six mining dams in the State of Pará, municipalities of Parauapebas, Paragominas and Canaã dos Carajás. The results showed, in the universe of analysis, dam B3 was the one with the highest failure rate (455.18), followed by the dam B1 (428.63) and the dam B2 (375,66). However, the dam with the highest risk for downstream areas was B2 with a Total Risk Index of 969.20 points, mainly due to the large number of possible people affected (12,900 people). This same dam is the one that would affect the greatest number of socioenvironmental components, defined then with possible cause of extreme damages. Compared with the risk analysis established in law, the RBPS analysis showed similarities, but more detailed in function of the four scenarios of analysis that will be generated, rather than just one. A risk analysis guide for dams was created as well, which came out from this present study.
Acesso aberto (Open Access)
Governança de risco em barragens de contenção de rejeitos: uma análise da lei de segurança de barragens e das entidades reguladoras
(Universidade Federal do Pará, 2022-12-16) PEREIRA, Oniwendel Felipe de Morais; RAVENA, Nírvia; http://lattes.cnpq.br/0486445417640290
Still in the first decade of implementation of the Dam Safety Law (LSB), three failures were recorded in Brazil in tailings containment dams with considerable socioeconomic and environmental impacts. These disruptions, at the beginning of the implementation of the LSB, draw attention to this important regulatory framework that should guarantee adequate Risk Governance and promote Brazilian society to support the strengthening of dam safety. In addition, observing other scenarios, such as the important region of the Amazon, where the State of Pará is located, one can observe a fact that reinforces the need to reflect on the safety of these structures, given that, according to SNISB data (ANA, 2021) is the second entity of the federation with the most dams for containing mining tailings, second only to Minas Gerais. Many concerns can be raised regarding the safety of these dams, one of them is a basic aspect, where the question is, does LSB present Risk Governance? And if it does, at what level is it present? Thus, this thesis aimed to analyze whether the LSB can be considered as having a low level of presence of Risk Governance and for this purpose, the hypothesis was formulated that a gap that exists in the LSB, tending to impair the safety of containment dams of tailings in Brazil, is caused by the adoption of a model with a low degree of Risk Governance. The question that guided the research hypothesis was: In comparison with the Risk Governance model developed by the IRGC (2017), as well as other models, can LSB be classified as low grade in terms of the presence of Risk Governance? The analysis was carried out by performing the structured comparison of the LSB with other models and to optimize this process, the Comparative Qualitative Analysis tool was used, through its variant Fuzzy Set QCA (fsQCA). Eight different cases were used as a basis for comparison and for the construction of causal conditions, the IRGC Risk Governance model (2017) was used. The results denied the hypothesis of this thesis, however, they contributed with final considerations relevant to the theme. Among them, it is noteworthy that most public entities that apply the LSB do not have full presence of Risk Governance in their regulatory frameworks, including SEMAS-PA, which only recently sought to start applying the LSB.
Acesso aberto (Open Access)
Longitudinal distribution of Chironomidae (Diptera) downstream from a dam in a neotropical river
(2013-08) PINHA, Gisele Daiande; AVIZ, Daiane; LOPES FILHO, Danilo Rezende; PETSCH, Danielle Katharine; MARCHESE, M. R.; TAKEDA, Alice Michiyo
The damming of a river causes dangerous consequences on structure of the environment downstream of the dam, modifying the sediment composition, which impose major adjustments in longitudinal distribution of benthic community. The construction of Engenheiro Sérgio Motta Dam in the Upper Paraná River has caused impacts on the aquatic communities, which are not yet fully known. This work aimed to provide more information about the effects of this impoundment on the structure of Chironomidae larvae assemblage. The analysis of data of physical and chemical variables in relation to biological data of 8 longitudinal sections in the Upper Paraná River showed that composition of Chironomidae larvae of stations near Engenheiro Sérgio Motta Dam differed of the other stations (farther of the Dam). The predominance of coarse sediments at stations upstream and finer sediments further downstream affected the choice of habitat by different morphotypes of Chironomidae and it caused a change in the structure of this assemblage in the longitudinal stretch.
Acesso aberto (Open Access)
Resistência e expropriação de famílias na Volta Grande do Xingu: o caso de duas áreas atingidas pela barragem de Belo Monte, Pará, Brasil
(Universidade Federal do Pará, 2013-05-28) MAIA, Ricardo Eduardo Freitas; GUERRA, Gutemberg Armando Diniz; http://lattes.cnpq.br/4262726973211880
This study made it possible to detail the mobilization against the construction of Belo Monte Hydroelectric Dam, from two distinct locations in Volta Grande do Xingu. Twenty six interviews have been made from May to July, 2012. The resistance against the construction of Belo Monte Dam spans over two decades, and it has gone through phases where there were position changes of the actors involved regarding the project, including the civil organizations. Regarding the peasants, these changes have dramatically influenced the way the conflict began, especially because their perception of the project depends upon the experience lived in the cited areas. In the municipality of São Raimundo Nonato and on the rural road connecting Ramal dos Penas, the mobilization turned possible due to the fear of changes, such as, losing their land and their production, the changes in their singular social relations grown in the area, the control in food production; however, such resistance emerged especially in those forced to leave the area, and the confrontations have been undermined fundamentally by the rapid social and environmental transformations after the beginning of the construction. In the areas named Ressaca, Garimpo do Galo and Ilha da Fazenda, one may notice that apart from the issues concerning the dam construction, there is the pressure as a result of the implementation of the mining project named Mineração Volta Grande. These expropriation fronts seem to increase even more the conflicts due to the changes in the construction area and the imminent displacement that may occur because of the mining project. Therefore, this study provides elements to the debate over other large investment projects that have undergone project or construction in the Amazon, followed by the peacemaking debate, the irreducibility in the construction, and consequently the natural displacement of residents for the progress and the common good, that overshadows lives and broaden social injustices.