A simulation of the migration of a cassava contaminant plume from a processing mill into aquifers, Eku, Delta State, Nigeria

Toxic effluents from cassava processing mills through leaching and percolation are transported into groundwater, which may be detrimental to the health of humans when consumed. Our knowledge on how these toxic effluents are transported into groundwater is limited and has not received the needed attention. The objective of the study is to stimulate groundwater flow and migration pattern of cassava effluents, stimulate the impact of recharge and discharge on the fate of cassava plume migration and, lastly to suggest a remediation techniques. Groundwater modelling system (GMS) software was used for the stimulation of migration of cyanide from the surface into groundwater. The results revealed that transport of Cyanide is considerably influenced by the subsurface geology of the unsaturated zone, groundwater recharge, pumping and dispersion rates, respectively. In a well at the source, a cyanide mass of 3.5 × 10⁵ mg was observed under increased recharge conditions for 7300 days and 7.6 × 10⁴ mg when reduced. Increased pumping rate for 7300 days, cyanide mass of 8.8 × 10⁴ mg was detected and it was 2.6 × 10⁵ mg when reduced. Increased dispersion results in 2.3 × 10⁵ mg and 3.1 × 10⁵ mg when reduced. Of these parameters simulated, recharge has the greatest impact on the transport of cyanide. The effectiveness of using MODFLOW and MT3DMS to understand the way cyanide is transported into groundwater is fully demonstrated. The pump-and treat remediation types is recommended for groundwater resource management and planning.