Radioactivity and radiological risk associated with effluent sediment containing technologically enhanced naturally occurring radioactive materials in amang (tin tailings) processing industry.
The processing of amang, or tin tailings, for valuable minerals has been shown to technologically enhance NORM and this has stirred significant radiological safety and health concerns among Malaysia's regulatory authority. A growing radiological concern is now focused on the amang effluent containing NORM in recycling ponds, since these ponds may be reclaimed for future residential developments. A study was carried out to assess the radiological risk associated with amang processing and the accumulated effluent in the recycling ponds. Twenty-six sediment samples from the recycling ponds of two amang plants in the states of Selangor and Perak, Malaysia, were collected and analyzed. The maximum activity concentrations of (238)U, (226)Ra, (232)Th and (40)K recorded in sediments from these ponds were higher than Malaysia's and the world's natural highest. Correspondingly, the mean radium equivalent activity concentration indices, Ra(eq), and gamma radiation representative level index, I(gammar), were higher than the world's average. The enhancement of NORM in effluent sediments as a consequence of amang processing, and the use of a closed water management recycling system created Effective Dose Rates, E (nSv h(-1)), that signal potential environmental radiological risks in these ponds, should they be reclaimed for future land use.
Bahari
Ismail
I
Nuclear Science Programme, Faculty of Science and Technology, National University of Malaysia, Bangi, 43600 Selangor, Malaysia. ismailb@pkrisc.cc.ukm.my
Mohsen
Nasirian
N
Abdullah
Pauzi
P
D000328:Adult; D003247:Conservation of Natural Resources; D019015:Geologic Sediments / Q000032:analysis*; D006801:Humans; D007220:Industrial Waste; D019216:Metals, Heavy / Q000032:analysis*; D008906:Mining; D011197:Potassium Radioisotopes / Q000032:analysis*; D011829:Radiation Dosage; D011834:Radiation Monitoring; D011848:Radioactive Pollutants / Q000032:analysis*; D018570:Risk Assessment; D014001:Tin; D014865:Waste Disposal, Fluid
D007220:Industrial Waste; D019216:Metals, Heavy; D011197:Potassium Radioisotopes; D011848:Radioactive Pollutants; D014001:Tin