Browsing by Author "Silva, E. Ferreira da"
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- An integrated investigation of the Rio tailings, Panasqueira mine, Centre PortugalPublication . Grangeia, Carlos; Ávila, Paula Freire; Matias, Manuel; Silva, E. Ferreira daThe risks associated with mine tailings have different nature and, thus, only a multiple approach can investigate and monitor comprehensively the characteristics and evolution of mine tailings impacts on the environment. Deposition at the Rio tailings (Panasqueira Mine) lasted about ninety years. Over one million cubic metres, of complex very fine to fine material, are deposited on a mountain side overlaying the Zezere river, increasing the risk of contamination of one of the most important hydrographic basins in central Portugal. Herein, a multidisciplinary study including geophysics, geochemistry and borehole information, organized in a GIS, is used to characterize the Rio tailings. The geophysical survey comprised ERT (Electrical Resistivity Tomography) and GPR (Ground Penetrating Radar) on the mud impoundment, as well as, on the slope of the tailings. The geochemical survey consisted on collecting water and tailings samples, iron coatings, arsenopyrite stockpile material and ferruginous crust. Samples collected in boreholes, drilled specifically for this project, were also analyzed. The GIS provided imaging of the geophysical, geochemical and particle size spatial distribution, so that comparisons between the different data sets are easily done. Resistivity and GPR allowed bedrock positioning. GPR was able to give layering results within the tailings. Finally, comparison and correlation between geophysical and geochemical results are carried out and evaluated on the GIS platform.
- Assessment of the soil contamination by potentially toxic elements in Aljustrel mining area in order to implement soil reclamation strategiesPublication . Candeias, Carla; Silva, E. Ferreira da; Salgueiro, Ana Rita; Pereira, H. Garcia; Matos, João Xavier; Ávila, Paula Freire
- Dust Characterization and Its Potential Impact during the 2014-2015 Fogo Volcano Eruption (Cape Verde)Publication . Candeias, Carla; Ávila, Paula Freire; Alves, Célia; Gama, Carla; Sequeira, Cristina; Silva, E. Ferreira da; Rocha, FernandoABSTRACT: Fogo (Fogo Island) is the youngest and most active volcano of Cape Verde. The last eruption occurred in 2014-2015. Aiming to assess the dust sources that impacted the air quality during the present study period, fresh lava samples were collected, while Saharan dust intrusions and transport were modeled. Rooftop dust was also collected on the island dwellings and a mineralogical and chemical characterization was undertaken. Air quality monitors were used to obtain concentrations of atmospheric particulate matter (PM) and gaseous pollutants. The mineralogical constitution was assessed by XRD and Electron Microprobe. The pseudototal chemical concentration was performed by XRF, ICP-MS and SEM; the latter includes particles morphology. During the study, WRF-CHIMERE results showed the intrusion of desert dust which affected the air quality. Lava was classified as tephritic to basanitic, with high potassium content. The Pollution Load Index for rooftop dust was > 1 in all samples, suggesting an enrichment. Higher values were found in dust size fraction < 63 mu m, with contamination factor pointing to high enrichment of As, Ni and Pb, and very high enrichment of Cd. The non-carcinogenic hazard estimated for children suggested that health problems may arise. The carcinogenic risk was above the target risk, mostly due to As > Pb > Co. Ingestion was the main exposure route. PM10 concentrations exceeded the 24-h mean of 50 mu g/m(3) recommended by WHO. Nevertheless, TVOCs displayed levels lower than guidelines. The highest levels of CO2 were recorded in more populated villages and farthest from the volcano.
- Geoquímica ambiental em áreas mineiras abandonadas do Norte de Portugal [Resumo]Publication . Bobos, Iuliu; Ávila, Paula Freire; Costa, Maria do Rosário; Silva, E. Ferreira da; Durães, Nuno
- Geoquímica urbana na cidade de Lisboa : controle de dados climatológicos na dispersão de poeiras contaminadasPublication . Bartolomeu, A. S.; Reis, A. P.; Patinha, Carla; Dias, A.; Cachada, A.; Prazeres, Cátia; Sousa, A. J.; Silva, E. Ferreira da; Batista, Maria Joao
- Roman slag distribution in the Portuguese sector of the Iberian Pyrite Belt [Abstract]Publication . Matos, João Xavier; Martins, A.; Rego, M.; Mateus, António; Pinto, A.; Figueiras, Jorge; Silva, E. Ferreira da
- Splitting and mapping soil samples in the vicinity of Panasqueira Mine according to harmful effects on human healthPublication . Salgueiro, Rita; Ávila, Paula Freire; Silva, E. Ferreira da; Pereira, H. G.
- URBSOIL-LISBON-Geoquímica dos solos e poeiras da cidade de Lisboa : caracterização e cartografia, suporte para futuros estudos de saúde humana : resultados preliminaresPublication . Prazeres, Cátia; Batista, Maria Joao; Patinha, Carla; Reis, A. P.; Dias, A. C.; Silva, E. Ferreira da; Cachada, A.; Sousa, A. J.; Figueira, R.; Sérgio, C.
- URBSOIL-LISBON-Geoquímica dos solos urbanos de Lisboa: caracterização e cartografia, suporte para futuros estudos de saúde humana: resultados preliminaresPublication . Prazeres, Cátia; Batista, Maria Joao; Patinha, Carla; Reis, A. P.; Dias, A. C.; Cachada, A.; Silva, E. Ferreira da; Sousa, A. J.; Figueira, R.; Sérgio, C.A Geologia, e em especial a Geoquímica em ambiente urbano, têm-se revelado ferramentas essenciais não só no estudo dos materiais naturais neste ambiente, como na ligação entre a Geologia e a acção antrópica. Este estudo, com uma metodologia que usa vários meios de amostragem, pretende avaliar quais os elementos químicos que podem intervir num contexto de interacção em que as crianças são tomadas como alvo principal. Os primeiros resultados sobre concentrações de elementos químicos para os solos urbanos de Lisboa apontam para uma exposição esparsa na cidade de alguns dos elementos químicos inorgânicos, mas havendo por vezes um zonamento por tipologia de local ou de elemento químico. Foram definidos quatro grupos de pontos de amostragem consoante o tipo de uso, e escolhidos para uma análise mais próxima alguns elementos considerados tendencialmente de input antrópico e que se relacionam com a saúde humana.