Modeling of 1-D nitrate transport in single layer soils

Abstract

There is increasing concern on environmental pollution especially potential of groundwater contamination by nitrates. The objectives therefore were to investigate the 1-D solute transport equation for single layer soil, calibrate, verify and apply model to field condition. The transport of nitrate in laboratory single soil columns of sand, laterite and clay were investigated after 21 days. The 1-D contaminant transport model by Notodarmojo et al (1991) for single layer soils were calibrated and verified using field data collected from a refuse dump site at avu, owerri, Imo state. The experimental distribution of nitrate along the sandy soil is linear with reduction rate of 0.44 ppm/cm, slightly exponential for laterite and clay with reduction rate of 0.136 ppm/cm and 0.24 ppm/cm respectively. The results show predicted transport was in close agreement with measured values with coefficient of correlation (R) ranging from 0.9 to 0.99. Application of the results in the prediction of possibility of pollution of groundwater was very promising.

Keywords: Contaminant transport, Nitrate, 1-D, column experiment