Red-mud basins and solid waste disposal site at KAP
Red-mud basins and solid waste disposal site at KAP. Red-mud is a by-product from the processing of bauxite in the alumina production, the main input material for the electro-chemical production of aluminum. It is the high alkalinity of the red-mud that causes high mobility of some heavy metals but also cyanide, fluoride and aromatic hydrocarbons from the basins are found in soil and groundwater. In time, without adding fresh red mud, the pH gradually decreases to more neutral levels, reducing environmental risks. The proposed remediation consists of draining basin water after treatment, reshaping, covering and stabilizing the impoundment slopes. The solid waste disposal site of 11 ha at KAP contains both hazardous and nonhazardous waste. Also this disposal site has been a substantial source of soil pollution, although disposal practices in recent years have somewhat improved because now waste categories are sorted and stored separately with hazardous materials stored on concrete surfaces, but still in the open and exposed to weather conditions. Remediation is costly due to the special nature of the waste, which contains toxic materials that require tailored techniques for containment and the fact that all materials needs to be removed, sorted and put in special cells for final disposal. To facilitate the disposal of future hazardous waste from KAP’s aluminum production, which is in principle the largest single source of hazardous waste production in the country, the remediation containment will designate a compartment that will not be closed as a separate cell for ongoing waste disposal with the same environmental protection standards to receive this waste.