Apatite group minerals : solubility and environmental remediation

![CDATA[Soils, wastes and waters contaminated by hazardous geochemical trace elements represent actual or potential threats to living organisms. Depending on the degree of environmental threat or the level of risk, contaminated systems may be subjected to remediation with the primary aim of reduction of the threat to an acceptable level. In this connection it is noted that the acceptable maximum contaminant level of a chemical element or substance is defined on a country-by-country basis, and may involve national or international standards. Several remediation techniques are available to remove, reduce or immobilize hazardous elements in wastes, soils and waters. Remediation processes based on chemical treatments aim to destroy contaminants or convert them into less environmentally hazardous forms [1]. Environmental problems that result from the contaminant’s high solubility can sometimes be solved by in situ immobilization by addition of appropriate reactants. Here, attention is drawn to the apatite group of minerals, and especially to the arsenate and phosphate members that contain calcium and lead. These have recognised applications, and limitations, in stabilization processes used for soils, wastes and waters contaminated by certain hazardous geochemical trace elements.]]