Monitoring of surface water with high dense pollution: Pirajuçara stream located at Metropolitan area of Sao Paulo

Abstract

Many projects have been developed trying to perform the diagnosis of water and soil contaminated by industrial sewage water, domestic discharge and solubilized products of toxic solid waste deposits. This subject was developed previously at Fapesp Project No 2002/04456-4 The use of magnetite as adsorbent material to fix heavy metals presents at contaminated sediment of the Ribeira de Iguape River. In spite of those studies there is a lack on the diagnosis and monitoring of the urban rivers and streams with flooding events, which cross big cities with dense population, located just few meters from streets, parks, offices and residences. Exploratory studies have been performed trying to establish the environmental diagnosis of those streams with high complexity with the variation of the water quality parameters measured seasonally, monthly, daily and also during the day with the variation of the results obtained in the morning in comparison with the results obtained in the afternoon. This project proposal intend to obtain financial support to the development of an adsorbent material main composed by diatomite to perform the water diagnosis of urban rivers and streams polluted by domestic and industrial liquid discharge, as have been observed at Pirajuçara stream located at metropolitan area of Sao Paulo. The study will indicate if the adsorbent bed composed by diatomite and glass coated diatomite on pellets can be used to monitoring and to the diagnoses process of water stream with dense pollution applying physical, chemical and biological analysis. The obtained results of this project will help on the evaluation of the water quality of urban stream and rivers with the development of the adsorbent material with after remain fixed under the water for few days will be analyzed and measured the toxic composition. It the results have the tendency to be equivalent of those present at the urban stream. The diatomite pellets will be also used as artificial substrate for algae growing as bioindicators after the deposition, quantification and identification will be performed. Since the beginning of the project the adsorption systems will be studied using the diatomite beds and water solutions with similar composition of the analyzed water samples for the determination of adsorption equilibrium time, equilibrium concentration, adsorption kinetics, thermodynamic constants and the agreement with Langmuir and Freundlich adsorption models. After those studies the adsorbent material can be modified accordingly with the requirements to most efficient measurements of toxic compounds present at stream water. The use of diatomite as adsorbent material and artificial substrate for bioindicators grow will provide important results to urban water diagnosis, about the presence of heavy metals, organic compounds, water eutrofization and the toxic condition of the urban stream. The study will provide additional information for further studies to be developed on water quality measurements of streams, rivers and water reservoirs located inside big cities which are suffering the effects of dense pollution. (AU)