Programa de P?s-Gradua??o em Engenharia Ambiental. N?cleo de Pesquisas e P?s-Gradua??o em Recursos H?dricos, Universidade Federal de Ouro Preto.Barragens s?o estruturas civis complexas do ponto de vista de seguran?a. Falhas nessas
estruturas podem se transformar em uma situa??o de emerg?ncia. O Plano de A??o Emergencial
(PAE) ? um documento oficial que identifica poss?veis condi??es de emerg?ncia em uma
barragem e as a??es a serem adotadas para prevenir e minimizar poss?veis danos em situa??o
emergencial. Um item primordial do PAE ? o Estudo de Inunda??o (dam break), o qual prev?
por meio modelos computacionais ?reas atingidas em um evento de ruptura. O conhecimento
dessas ?reas permite que a Defesa Civil prepare e colabore com a popula??o sob risco,
assegurando sua integridade em caso concreto de rompimento. Isto posto, esta pesquisa se
prop?s a estudar o conte?do do estudo de dam break de barragens de alto dano potencial do
Quadril?tero Ferr?fero (QF) e a percep??o de agentes da Defesa Civil municipal no
planejamento e gest?o de a??es emergenciais. Para tanto, foram visitadas 19 Coordenadorias
de Defesa Civil Municipal (COMPDEC) da regi?o do QF. Nas visitas foram requisitadas c?pias
dos PAEs (para an?lise dos dam break) e aplicados question?rios estruturados para an?lise da
percep??o dos agentes daquelas ag?ncias. Verificou-se que todos os dam break apresentam os
itens: estudos hidrol?gicos, defini??o do modo de falha e hidrograma de ruptura, e propaga??o
e mapeamento da onda de ruptura no vale a jusante da barragem. Um aspecto positivo dos
estudos foi a utiliza??o de malhas topogr?ficas precisas para constru??o do modelo, o que
garante maior precis?o na delimita??o da mancha de inunda??o. Apesar disso, os estudos
apresentaram defici?ncias como falta de informa??es de metodologia e da abordagem dos
rejeitos como flu?do n?o-newtonianos, sendo que a primeira dificulta a avalia??o do estudo e a
?ltima interfere diretamente na defini??o de extens?o da mancha de inunda??o e na previs?o de
danos em eventual vazamento de rejeitos. A an?lise de percep??o dos agentes de Defesa Civil,
mostrou que estes entendem a import?ncia do PAE e do dam break em sua atua??o na
prepara??o ? situa??o de emerg?ncias. Mostrou tamb?m que algumas Defesas Civis do QF
dependem das empresas para obten??o de informa??o das barragens e para o planejamento e
execu??o dos exerc?cios simulados. Apesar disso, de forma geral as Defesas Civis municipais
t?m se mostrado protagonistas na prepara??o a emerg?ncias, principalmente ap?s os ?ltimos
desastres com barragens de rejeitos em Minas Gerais. Por fim, este estudo mostrou como a
integra??o entre a teoria (estudos de dam break) e a pr?tica (atua??o das Defesas Civis) ?
fundamental na preven??o e prepara??o em situa??es emergenciais com barragens de rejeito de
minera??o.Dams are complexes civil structures from a security point of view. Failures in these structures
can become an emergency. The Emergency Action Plan (EAP) is an official document that
identifies possible emergency conditions in a dam and the actions to be taken in order to prevent
and minimize possible damage in an emergency. A primary item of the EAP is the Inundation
Study (dam break), which forecasts through computational model areas affected in a rupture
event. The previous knowledge of these areas allows the Civil Defense to prepare and
collaborate with the population at risk, ensuring their integrity given the event of a disruption.
That being said, this research aimed to study the content of the dam break study of high potential
damage dams in the Quadril?tero Ferr?fero (QF) and the perception of municipal Civil Defense
agents in the planning and management of emergency actions. To this end, 19 Municipal Civil
Defense Coordinators (COMPDEC) of the QF region were visited. During visits, copies of
EAPs were requested (for dam break analysis) and structured questionnaires were applied to
analyze the perception of agents at those agencies. It was found that all dam breaks have the
following items: hydrological studies, the definition of the failure mode and rupture
hydrograph, and propagation and mapping of the rupture wave in the valley downstream of the
dam. A positive aspect of the study was the use of precise topographic meshes for the model?s
construction, which guarantees greater precision in the delimitation of the flooded spot. In spite
of this, the studies revealed deficiencies such as lack of information on methodology and on the
approach of tailings as non-Newtonian fluid, the former hindering the evaluation of the study
and the latter directly interfering the definition of the extension of the flood spot and in the
forecast of damage in the eventual leakage of tailings. The perception analysis of the Civil
Defense agents showed that they understand the importance of the PAE and the dam break in
their performance in the preparation for the emergency. It also showed that some QF?s Civil
Defenses depend on companies to obtain information on dams and to plan and execute the
simulated exercises. Despite this, in general, the municipal Civil Defenses have shown
themselves to be protagonists in emergency preparedness, mainly after the last disasters with
tailings dams in Minas Gerais. Finally, this study showed how the integration between theory
(dam break studies) and practice (performance of Civil Defenses) is fundamental in the
prevention and preparation in emergency with mining tailings dams