Banca de DEFESA: NELIZE LIMA DOS SANTOS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : NELIZE LIMA DOS SANTOS
DATE: 24/01/2022
TIME: 10:00
LOCAL: RNP-UFBA - Instituto de Geociências
TITLE:

EXPOSURE TO TOXIC METALS FROM THE MINING TAILINGS IN BASIN
ABANDONED IN BOQUIRA/BA 

KEY WORDS:

Abandoned mining, Tailings basin, Atmospheric dispersion model

PAGES: 59
BIG AREA: Ciências Exatas e da Terra
AREA: Geociências
SUBÁREA: Geologia
SPECIALTY: Geologia Ambiental
SUMMARY:

The abandonment of mining activity in the city of Boquira/BA resulted in one of the greatest environmental liabilities arising from mining in Brazil. Over the years, due to demographic expansion, the tailings basin has been incorporated into the municipal urban area, increasing the vulnerability of this area to exposure to toxic components of the tailings basin.This work aims to present the results obtained from the assessment of exposure of the urban area of Boquira/BA to contaminants in the tailings basin. For this, at first, a conceptual model of exposure to contamination was built, considering the airways as the main means of transport, due to the climatic characteristics of the region, later, a model was developed with three domains (houses, streets and air) in the Matlab R2014a software, having as input data the information referring to the meteorological conditions of the region, specifically, wind direction and speed, and using for calibration the chemical analyzes of lead contamination obtained in street sediments and dust from houses distributed throughout of the urban area. The results of the conceptual analysis showed concentrations of heavy metals in the urban area of the municipality, above the prevention and investigation limits established by CONAMA Resolution 420/2009, in the four defined exposure scenarios, while the simulation carried out over a period of one year suggested that most lead is concentrated in streets or houses rather than suspended in the air. The simulations carried out for hypothetical future scenarios, considering an eventual remediation of the tailings pond, showed that after 200 days the concentrations in the air and in the streets decreased considerably and in the houses it stopped accumulating. In general, the model was able to reproduce the atmospheric dispersion process in the area and presented a satisfactory response in the estimation of lead concentrations in the analyzed domains, proving to be appropriate to assist in the assessment and management of contaminated areas through atmospheric dispersion.

BANKING MEMBERS:
Presidente - 2298240 - LUIZ ROGERIO BASTOS LEAL
Interno - 1005053 - HARALD RENE KLAMMLER
Interna - 3071908 - MARIA DA CONCEICAO RABELO GOMES
Interno - 1847453 - RICARDO GALENO FRAGA DE ARAUJO PEREIRA
Externo ao Programa - 1219972 - SANDRO LEMOS MACHADO
Externo à Instituição - FRANCISCO INÁCIO NEGRÃO