DEGEO - Departamento de Geologia

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/8

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2007 - 200912010 - 20131

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Autor: search.filters.author.Nalini Júnior, Hermínio AriasAssunto: search.filters.subject.Groundwater

Resultados da Pesquisa

Agora exibindo 1 - 2 de 2
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    Influence of the natural oxidation of the leachate organic fraction from a landfill on groundwater quality, Belo Horizonte: Minas Gerais, south-eastern Brazil.
    (2013) Barella, Cesar Falcão; Bacellar, Luis de Almeida Prado; Nalini Júnior, Hermínio Arias
    The objective of this work was to evaluate the influence of the natural degradation of the leachate organic fraction from the Belo Horizonte landfill on groundwater chemical evolution. The work focused on the modifications introduced by redox reactions in the presence of terminal electron acceptors. Twenty-one sampling points distributed along 13 monitoring wells were selected for the analysis of the chemical indicators of interest (TDS, SO4 -2, Fe?2, Ba, pH and Eh). The behaviour of the variables involved in the alteration of the water quality was assessed by the spatial distribution of target parameters, elaboration of redox diagrams and chemical modelling that focused on the determination of mineral saturation indexes. The study showed a trend toward pyrite precipitation, which leads to the removal of chemical species such as divalent iron and sulphur as sulphide from the system. This removal disturbs the chemical equilibrium, typically by moving the reactions to replenish the sulphate concentration present in the groundwater. This process occurs primarily through the dissolution of compounds that have sulphate in their chemical composition, such as barite, suggesting that part of the barium concentration in the subsurface can be of geogenic origin. This study demonstrated the importance of knowing the nature of the geochemical processes in groundwater contaminated by urban solid waste.
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    Arsenic in the groundwater of Ouro Preto (Brazil) : its temporal behavior as influenced by the hydric regime and hydrogeology.
    (2007) Gonçalves, José Augusto Costa; Lena, Jorge Carvalho de; Paiva, José Fernando de; Nalini Júnior, Hermínio Arias; Pereira, Janice Cardoso
    In the city of Ouro Preto (MG), water catchment for public supply originates from superficial drainage, springs, old abandoned mines and some driven wells. In the rocks of the region, As is originally found in gold-enriched sulphide-bearing mineral deposits. The weathering process introduces As into the hydrological system by dissolution of this element into the leachate. Measurement of the As content in the groundwater of some catchments was carried out during 1 year and these measurements demonstrated high As content—up to 224 lg L–1 of As(V)—during the rainy season (the maximum concentration limit according to World Health Organization is 10 lg L–1). Lower values were observed during the dry season and in some sampling stations, As was not even detected. The As concentration variability during 1 year shows a strict and direct relationship to seasonal and hydrological conditions. For city authorities, responsible for public water supply, it is necessary to perform a complete inventory of the water sources used and constantly monitor the As content in the water.