This report outlines the theoretical risks and costs associated with rehabilitating Jeebropilly West Pit, to five different land-uses. The risks and costs for each land use are calculated using, ACARP Risk Assessment and Cost-Effectiveness Tool. The results of this study are summarized below.
The risks calculated for each rehabilitation method are ranked on a scale between 0 - 5. Zero indicates that there is no risk involved in rehabilitating. The risks are calculated by assigning ‘likelihoods of failure’ to critical rehabilitation parameters. These parameters include issues concerning, landform instability, downstream water quality, groundwater impact, vegetation failure, animal failure, poor perception and negative socio-economic impact. Each parameter also requires input of consequences. After all the likelihoods and consequences of failure have been entered into the program, an overall ‘risk of failure’ can be calculated. As shown in the table above, the rehabilitation method most likely to fail is Cropping (2.3). Returning the land to its Native Habitat is calculated as having the least chance of failure (0.14). The costs associated with each post-mining land use are simply calculated by entering the prices incurred by developing each rehabilitation method.
The Overall ranking is determined by the rehabilitation method that has the best risk to cost ratio. The relative costs associated with each method are scaled down to ensure the overall outcome is not too economically influenced.
The results shown in the results Table1 above indicate that doing nothing is the most suitable option for rehabilitation, followed by native habitat. The recommendation is this study have suggested that Grazing is the most suitable land use for Jeebropilly West Pit. This conclusion has been based on the fact that, doing nothing causes will cause an ‘outrage factor’ in the publics eye. Native habitat in Jeebropilly requires approx fifty years of maintenance until it is established. This time-line far exceeds the current mining lease of 18months. Rehabilitating the land for grazing is the next ‘most suitable’ option. It is well suited to the area due to ideal climate conditions and surrounding properties willing to maintain the rehabilitated land.