Geochemical analysis of sediments from a polluted waterway in the vicinity of a metallurgical plant, Minas Gerais, Brazil

Mining and metallurgical industries are the most responsible for heavy metal contamination. These contaminants are often associated to poor management strategies and the lack of suitable containment areas. This is the case of one of the largest metal alloy producers in the São Francisco river basin, in Minas Gerais state, Brazil. During operation, the tailings of this activity have been accumulated in the surrounding area, leading to heavy metal contamination (Mn, Cu, Zn, Ni, Pb, Cd, Cr and As), much above the critical levels, which accumulate in the sediments of the nearby waterways, in the soils of the drainage area, and in the water column. In this work we are going to discuss both the contamination level and its extent in the Consciência river, a small tributary of the São Francisco river, the longest river entirely Brazilian, by analyzing the geochemistry and mineralogy of the accumulated sediments. It will be also discuss the reclamation strategies of this site and the impact on the environment.

Biological Approaches for Remediation of Metal-Contaminated Sites

Environmental pollution by several heavy metals and metalloids is a severe problem worldwide, as soils became increasingly contaminated, posing a threat to ecosystems and ultimately to human health. Contamination derives from large scale urbanization and industrialization, threatening land ecosystems, surface and groundwater, as well as food safety and human health. Remediation strategies for heavy metal-contaminated sites are necessary to protect from their toxic effects and conserve the environment for future generations. Numerous physicochemical techniques have been adopted including excavation and deposition in landfills, thermal treatment, leaching and electro-reclamation. These techniques are fast but inadequate, costly, cause adverse effects on soil physical, chemical and biological properties, and may lead to secondary pollution. In fact, many of these approaches only change the problem from one form or place to another, and do not completely destroy the pollutants. There was an urgent need to develop new technologies which are cost-effective and eco-friendly. In this context, biological remediation has tremendous potential. It uses plants and microorganisms to remove or contain toxic contaminants and is considered as the most effective method because it is a natural process, environmentally-friendly, has a low cost, and wide public acceptance. The present chapter aims to provide a comprehensive review of some of the promising processes mediated by plant and microbes to remediate metal-contaminated environments. Some biological processes used for the decontamination of organic compounds will also be included because of their relevance and potential common use for both purposes.

Integração e recuperação paisagística em pedreiras

Esta dissertação, elaborada no âmbito da obtenção do grau de mestre em Arquitetura Paisagista, tem como tema a “Integração e Recuperação Paisagística em Pedreiras”, a qual foi desenvolvida com base no trabalho de investigação desenvolvido, enquanto colaborador no Centro Tecnológico da Pedra Natural de Portugal (CEVALOR) localizado em Borba, desde o ano 2000, até à atualidade. A recuperação de pedreiras pode ser caracterizada, como um processo de intervenção local, inserido no âmbito da gestão visual, da conservação e de valorização da paisagem. Para realizar o processo de recuperação, não só é necessário o correto enquadramento legal, como entender o contexto paisagístico, que permite avaliar os impactes visuais potenciais e propor medidas de mitigação adequadas. O conteúdo metodológico desta dissertação apresenta a análise, interpretação e caracterização estrutural da paisagem assim como da avaliação do impacte visual, assim como as opções de recuperação com vista à sua integração das pedreiras na paisagem; Abstract: Integration and landscape reclamation in quarries This dissertation concerning the theme “landscape integration and rehabilitation of quarries” aims to obtain the master degree in landscape architecture, as the result of my research as a collaborator at CEVALOR since the year of 2000. The integration and rehabilitation of quarries can be described has a process of local intervention within the fields of visual management, conservation and amelioration of the landscape. In order to accomplish the rehabilitation process, not only is necessary to consider all legal obligations but understand the landscape context, through the analysis of the visual quality and the assessment of the visual impacts in order to propose the most adequate mitigation measures. This dissertation presents a methodological approach that describes the process of landscape analysis, landscape visual impact assessment and the feasible rehabilitation options regarding the visual integration of quarries in the landscape.