Author(s)

Haniel Torres

Discipline of Environmental Earth Science, James Cook Univ., Townsville, Australia.

One of the most serious and important environmental issues related to the mining sector in Central Queensland is the contamination of abandoned mine sites. Representative of this issue is the abandoned Mount Morgan gold mine. The potential dispersal of acid mine drainage (AMD), a product of more than 100 million tons of sulphide-rich waste rock, into the surrounding environment, is the most challenging environmental problem currently facing this abandoned mine site. The abandoned Mount Morgan gold mine has multiple pollutant species that involve complex geochemical processes. The present study simulated the flow and transport processes founded on hydrological and geochemical conditions of the real-life field at the mine site. To assess the groundwater contamination risk and detect unknown pollution sources, few chemical species such as Iron and Sulphur were considered as the contaminants. The flow model was simulated using the computer code MODFLOW, and PHT3D was used for the simulation of advection, dispersion and chemical reactions of constituents dissolved in this groundwater system, and to mimic the reactive chemical transport processes in the polluted groundwater. To improve on results from other studies (Datta et al., 2017; Scotney, 2016; Doyle, 2016), a calibrated model was a main focus for this study. Field concentration measurements were matched with the flow simulation outcomes to calibrate the model. The results obtained showed a great potential to model transport of contaminants in the groundwater system using a real-world situation.

Groundwater Contamination, Source Characterization, PHT3D, Chemically Reactive Transport Simulation, Mine Site Contamination

Torres, H. (2020) Assessing Groundwater Contamination Risk and Detection of Unknown Sources Using a Multi-Component Reactive Transport Model. Journal of Geoscience and Environment Protection, 8, 132-158. doi: 10.4236/gep.2020.85009.