NORM situation in non-uranium mining in China.

The Ministry of Environmental Protection in China is responsible for regulatory control on radiation protection from naturally occurring radioactive material (NORM). The natural radiation caused by human activities is a major contributor to public and occupational exposure in China. This paper introduces the first national census on pollution sources (target year 2007) in China, and describes NORM sites in Baotou, Inner Mongolia, one of the largest rare earth deposits in China. The ores are rich in radioactive elements, with a concentration of ThO(2) of 0.01-0.05% and concentration of U(3)O(8) of 0.0005-0.002%. The large amount of NORM residues is regulated and controlled. After treatment of the waste water, it is discharged into tailing ponds and then pumped directly to milling plants for re-use. The waste gas after off-dust cleaning is discharged into the environment. A substantial amount of blast furnace iron slag from the waste treatment is transformed into cement, concrete, and bricks, or used directly for highway construction. This raises a serious environmental concern. As a result, environmental radiation monitoring and assessment have been introduced recently. Regulatory control of NORM is very important in order to take effective measures to lower the dose.