1.Rare earth elements (REE) or Rare Earth Oxides (REO) occur as Monazite in nature, monazite is a phosphate mineral comprising mainly of the light REE especially Ce, La, Nd and Pr. The mineral also contains considerable amount of heavy REE such as Y and the radioactive element Thorium. These rare earth metals bind with PO4 to form Monazite (ref: Wikipedia). At once, the Monazite mineral and the soils, sand, rocks etc will be mined from Mt. Weld. The Mt. Weld mine deposits contain 8% - 12% of (REO) with approx. 400 ppm Thorium.
2.The Mt. Weld mine ore will be then transported to the Concentration Plant, where the mineral is separated from the unwanted soils, sand and rocks. The products from the concentration plant, also known as concentrates, is primarily the monazite mineral, contains approx. 40% REO with 1600 ppm Thorium. This product will be shipped from Australia to Gebeng, some 4000 km away, for further processing.
3.At LAMP, the aim of the process is to extract the 40% REO from the concentrates to produce the high purity REO. Other chemicals such as sulphuric acid, ammonia and magnesium hydroxide will be added to the process for extraction and purification of the rare earth metals.
4.What is in the waste sludge are mostly phosphates, gypsum, magnesium and Thorium compounds. Note 40% of the concentrates has been extracted as REO product, hence the Thorium concentration left in the waste is significantly higher than that of the concentrates, Lynas failed to clarify the exact Thorium concentration in waste. In terms of quantity however, approx. 120 tonnes of Thorium will be produced from LAMP every year (ref: Malaysia Insider, 12th Apr 2011: Interview with N Curtis).
5.The final valuable REO products will then be exported to US, Europe and Japan, what left in Malaysia is the abundance of waste, including the radioactive Thorium-bound wastes, of which Lynas has no detailed plan for treatment, disposal and storage (ref: Malaysia Insider, 12th Apr 2011).
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