Avaliação da concentração de nitrato nas águas subterrâneas no bairro do Farol, em Maceió, Alagoas

Abstract

Throughout history, some confirm the use of the underground as final destination of residues produced for the activity human being. With the growth of the urban centers and the necessity, each bigger time, of a safe water source for supplying of the populations and food production, hás intensified the use of underground Waters, face to its lesser cost for production and treatment. On the other hand, this action if hás shown preoccupying, therefore it has resulted in a big explotation of water-bearing in regions where if it observers high vulnerability to the contamination of underground Waters. The city of Maceió, State of Alagoas, hás in these, the main source for the water supply of its population. the Farol’s quarter, located on two important water-bearing sedimentary ones, shelters a population of more than 60 thousand inhabitants and occupies an area of 3 km2, being considered na important commercial and residential Center of Maceió. Although to possess 75% of its area taken care of for collecting public net of sewers, only 7,8% of the domiciles of the quarter contribute for the some one. The remain has its sewers made use in septic tank with absorbent hole, that for bad operation, finish IF constituting in a focus of infiltration of contaminants in the ground, reaching, many times, the water sheet. The work had as objective the evaluation of the nitrate concentrations in underground Waters of the quarter, using the analytical methodology of the Reducing Column of Cadmium-Cover of the Standard Methods Will be the Examination of the Water and Wastewater. The research evaluated the nitrate concentrations in caught underground water samples in 14 points of sampling distributed by the quarter, in water-bearing Barreiras and Marituba, having been confirmed the presence of this íon in the 4,97 concentrations that had varied of 2,21 mg/L of NO3--N. although these values to meet below of the maximum limit allowed by Low in the 518/04 of the Health department, that establishes the Standards of Potability for the water, 85,7% of simples had presented concentration above of 3,0 mg/L of NO3--N, what it configures as indicative of contamination of undergound Waters of the quarter for nitrates in tolerable dosage.