Estimation of Lead (Pb) Flux, Distance of Travel and Break through Time Using Convective Flux Equations: A Case Study of Farmlands around Lead (Pb) Contaminated Goldmine in Zamfara Nigeria

摘要

Estimating the transport and fate of chemicals released into the environment is an interesting and challenging task. The global environment is diverse on the chemical transport and fate scale. This paper applies the mathematics of convection to estimate the extent of lead (Pb) as it travels towards ground water. Highest flux (q_s) value of 9.62 X 10-3 cm hr-1 was obtained at the initial time of estimation (72 hours) while the lowest q_s value estimated is found to be 1.58 X 10-7 when the highest time (438000 hours) was used in the estimation. Break through values ranged from 17822.57-1.08 X 108 hr-1 in Dareta North, while it ranges from 11275.5-68592631 hr-1 in Dareta South. The results for estimated values of Pb flux, distance of travel and breakthrough time using convective flux equations in the study area suggests that Pb travel through the soil down the groundwater at an increasing flux as this will require immediate measures to curtail this. As the break through time needed for Pb to travel at a distance of 3.46 x 10-3 cm hr-1 with a qs value of 3.81 x 10-4 cm hr-1 through the soil to the ground water (with at distance of 10 m from the ground) after ten years if all things being equal is estimated to be 289080 hr-1.