Mathematical Models for Predicting Pollutant Transport in Soils at Decayed Waste Dumpsites of Gwari Market, Yola, Nigeria

Abstract

Due to the careless siting of human activities in Nigeria, resultant pollutants pass through porous soils to pollute the underlying groundwater resources. Consequently Darcy’s Experimental set-up of Falling Head Permeability test was used to determine the velocities and travel distances of pollutants through soils leached from Gwari market waste dumpsites with a view to formulating mathematical equations for predicting the transport of pollutants through the porous soil media so as to safeguard the groundwater resources of the area. The dumpsite open year is (1999), 15 years old and spread on an area of 3.2 hectares with capacity of 60,000 tons. Results showed that the model advection velocity of 0.03845cm/sec. obtained is approximately equal to the observed laboratory velocity value determined as 0.03963cm/sec. Also, a model travel distance of 19.3cm obtained is approximately equal to an observed distance of 20cm determined in the laboratory. The analyses done implied that the models can be used to predict if pollutants from a dumpsite would travel to a river channel due to advection and dispersion processes within a specific given period which is a good pollution management strategy. The study recommended that in the planning and management of the physical environment, the knowledge of pollutants vertical velocity through porous soils should be integrated into water resources management for evaluating the effectiveness of pollutants mitigating alternatives, and in risk assessment to ensure environmental sustainability.

Keywords: mathematical models, pollutants, vegetable dumpsites, velocity, transport.