CONCENTRAÇÕES DE NITRATO NAS ÁGUAS FREÁTICAS DA CIDADE DE ANASTÁCIO (MS) E SUAS IMPLICAÇÕES AMBIENTAIS

Abstract

ABSTRACT To nitrate conventions determination at Anastácio city water tables, 15 wells distributed in 4 sectors of the city had been selected: 7 wells at Vila Umbelina sector, 1 well at Center sector, 2 at Vila Rodrigues and 5 at Vila Flor sector. The temporal analysis consisted of grouping and relating the data proceeding from samplings carried through in 1997, 2000 and 2001 against the data gotten in 2003. The 1997 results had been part of Pinto studies (1998) and the data between the spring/00 and the winter/01 had been gotten from Ayach (2002). For the 2003 studies the seasonal analysis was chosen distributed in the summer, autumn, winter and spring/03. The nitrate samplings, preservations and analysis (espectrophotometric method in the UV region) in the 3 studies had followed the orientations described at APHA (AMERICAN…, 1995). At the three monitored periods the nitrate concentrations at Vila Umbelina, Vila Rodrigues and Vila Flor sections had been found on an average superior to the maximum value permitted (VMP) of 10 mg N-NO3 L-1. The Center sector presented concentrations in accordance with the VMP band, being classified according to the Index of Nitrate Concentration in Underground Waters in 1997 and 2003 with the concept Bad and in 2000/2001 Good. The others sectors had presented high nitrate contaminations in practically all the samplings, having contributed so that to the average concentrations were above of 15 mg N-NO3 L-1. They were classified as Awful, exception to Village Flower sector in 2000/2001 with the concept Bad. Key words: Nitrate. Basic Sanitation. Water Table Contamination. Environmental Quality. Water Resource. Anastácio (MS).