Revista Águas Subterrâneas (Dec 2015)

Nitrate concentration in groundwater of rural areas from São José do Rio Preto (SP), Brazil

  • Cinthia Cristine de Moura,
  • Didier Gastmans,
  • Chang Hung Kiang,
  • Rosângela Pacini Modesto,
  • Paulo Fernando Rodrigues,
  • Elaine Cristina Ruby,
  • Andrey Vetorelli Borges

DOI
https://doi.org/10.14295/ras.v29i2.27980
Journal volume & issue
Vol. 29, no. 3
pp. 268 – 284

Abstract

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Several studies, carried out in many countries, have connected agricultural practices with nitrate contamination in groundwater. In São Paulo, the monitoring program of groundwater quality, conducted by the Environmental Agency of São Paulo State (CETESB), indicate an increase in nitrate concentrations in Bauru Aquifer System (BAS). However, in rural areas the extent of this problem is unknown. In order to assess the nitrate contamination, quality and the chemistry of BAS groundwater in rural area from São José do Rio Preto, activities encompassing the record of agricultural proprieties, two groundwater sampling campaigns for chemical analysis, statistical analysis of hydrochemical data and evaluation of the relationship between nitrate concentrations in groundwater and agricultural practices have been undertaken. Only two samples, in both sampling campaigns presented nitrate concentration higher than the limit for drinking water established by Ordinance MS 2914/2011. Nevertheless, several samples presented evidence of contamination; especially in wich nitrate concentration show good correlation with chloride, indicating impairment and changes in water composition. Effects of groundwater contamination were observed in proprieties where livestock associated to agricultural activities are developed, and the source of contamination is associated with sanitation systems in situ, in addition to accumulation of animal waste.

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