Dispersion of pollutants in watercourses intercepted by highway BR-050, in the Triangulo Mineiro region, Minas Gerais, Brazil/Dispersao de poluentes em cursos de agua interceptados pela rodovia BR-050, na regiao do Triangulo Mineiro, Minas Gerais, Brasil

• Published in: Acta scientiarum. Technology 2016-04, p.153
• Main Authors: Pereira, Carlos Eugenio, Salla, Marcio Ricardo, Frasson, Vanessa Maria, Filho, Jose Eduardo Alamy, de Lima, Guilherme
• Format: Article
• Language: Spanish
• ISSN: 1806-2563
• DOI: 10.4025/actascitechnol.v28i2.27742

Models based on the diffusive-advective equations are valuable tools for forecasting of contamination levels downstream from spill points. These models require field parameters for validation. The longitudinal dispersion coefficient [E.sub.L], which translates the transport potential of dilute pollutant is amongst the most important parameters. Based on field techniques using saline and fluorescent tracers, this study determined the [E.sub.L] in three streams intercepted by highway BR-050, all located in the Paranaiba River Basin. The discrepancy ratios (Rd) of some experimental methods and equations reported in the literature were analyzed and compared with the standard routing procedure. Comparing the results of the Moment (statistical), the Chatwin, the peak concentration and the crown concentration methods, the lowest discrepancy ratios were obtained for the latter two methods. Ribeiro, Silva, Soares, and Guedes (2010) also showed that the peak concentration and the crown concentration methods produce the lowest discrepancy ratios. The analysis of contamination scenarios clearly illustrates the direct relationship between pollutant transport capacity and water discharges in natural watercourses. Keywords: Bom Jardim Stream, Jordao river, saline tracer, fluorescent tracer, longitudinal dispersion coefficient. Os modelos baseados nas equacoes de difusao-adveccao constituem valiosas ferramentas para previsao dos niveis de contaminacao a jusante do ponto de derramamento. Tais modelos necessitam de parametros obtidos em campo para sua validacao, dentre os quais se destaca o coeficiente de dispersao longitudinal [E.sub.L], que traduz o potencial de transporte de um poluente diluido. Por meio da aplicacao de tecnicas de campo, com o uso de tracadores salino e fluorescente, neste estudo foi determinado [E.sub.L] em tres corregos situados na bacia hidrografica do rio Paranaiba e interceptados pela rodovia BR-050. Foram feitas analises da razao de discrepancia Rd de alguns metodos experimentais e equacoes da literatura em comparacao ao metodo padrao routing procedure. Os resultados dos metodos Momentos (estatistico), Chatwin, pico de concentracao e coroa de concentracao foram comparados e as menores razoes de discrepancia Rd foram obtidas para os dois ultimos. Ribeiro et al. (2010) tambem mostraram que o metodo pico de concentracao e coroa de concentracao apresentam Rd menores. As analises dos cenarios de contaminacao ilustram claramente a relacao direta que exi