ABSTRACT
The following information should be ascertained concerning those characteristics of the waste that may have environmental effects:
• toxicity of the waste, e.g. its content of fluorine, arsenic, lead, nickel or similar toxic or heavy metal salts;
• possible radioactivity of the waste and other potential health hazards, e.g. free asbestos content;
• the soluble solids content of the waste and its acidity or alkalinity as it leaves the mill;
• the effect of weathering and oxidation on the above. (For example, insoluble sulphides may be oxidized to produce soluble sulphates and sulphuric acid.)
• The possibility of spontaneous combustion of the waste. • The possibility of the soluble chemical content of the waste precipitating out in
the underdrain system of the storage, e.g. by the precipitation of insoluble Fe2O3 gels in the drainage filters or adversely affecting the properties of pond linings. (e.g. Clay may become rigid and brittle when in contact with calcium hydroxide or phosphoric acid, or a sodium bentonite may be converted to a less impermeable calcium bentonite.)
• Decomposition of certain contents of the waste may produce radioactive combustible or toxic gases, e.g. radon, or methane which will emanate from the storage.
