5.4. Waste from mining and mineral processing is usually disposed of on or near the ground surface, but the manner and the large volumes in which the waste arises, its physicochemical form and its content of long lived radionuclides of natural origin distinguish it from other radioactive waste. The waste is generally stabilized in situ and covered with various layers of rock and soil. Such disposal systems cannot be designed to provide absolute containment at all times and, thus, the strategy is to control any release of radionuclides to the environment such that an unacceptable dose does not occur. Risks associated with this type of facility may be dominated by chemical and physical risks, such as the long term release of potentially toxic elements and structural failure of the facility. As a result, greater emphasis will be placed on the presence of radionuclides and associated chemicals in the surrounding environment, which act as a reliable indicator for the performance of the disposal system.