Surface Water Contamination by Uranium Mining/Milling Activities in Northern Guangdong Province, China
Journal
Clean - Soil, Air, Water
Journal Volume
40
Journal Issue
12
Pages
1357-1363
Date Issued
2012
Author(s)
Abstract
The northern region of Guangdong Province, China, has suffered from the extensive mining/milling of uranium for several decades. In this study, surface waters in the region were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) for the concentrations of uranium (U), thorium (Th), and non-radioactive metals (Fe, Mn, Mg, Li, Co, Cu, Ni, and Zn). Results showed highly elevated concentrations of the studied radionuclides and metals in the discharged effluents and the tailing seepage of the U mining/milling sites. Radionuclide and heavy metal concentrations were also observed to be overall enhanced in the recipient stream that collected the discharged effluents from the industrial site, compared to the control streams, and rivers with no impacts from the U mining/milling sites. They displayed significant spatial variations and a general decrease downstream away from upper point-source discharges of the industrial site. In addition, obvious positive correlations were found between U and Th, Fe, Zn, Li, and Co (R2>0.93, n=28) in the studied water samples, which suggest for an identical source and transport pathway of these elements. In combination with present surface water chemistry and chemical compositions of uraniferous minerals, the elevation of the analyzed elements in the recipient stream most likely arose from the liquid effluents, processing water, and acid drainage from the U mining/milling facilities. The dispersion of radionuclides and hazardous metals is actually limited to a small area at present, but some potential risk should not be negligible for local ecosystem. The results indicate that environmental remediation work is required to implement and future cleaner production technology should be oriented to avoid wide dispersion of radioactivity and non-radioactive hazards in U mining/milling sites. Results from this preliminary environmental assessment indicate that radionuclides and other non-radioactive metal concentrations in the U mining/milling discharged effluents and tailing seepages largely or moderately exceeded the drinking water safe limit given by the Chinese National Guideline. A potential risk exists for local ecosystem through using this U-polluted stream-water for irrigation, watering, and direct consumption. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Subjects
Heavy metal; Radionuclide; Water pollution
SDGs
Other Subjects
chemical composition; drinking water; effluent; environmental assessment; heavy metal; radionuclide; surface water; thorium; uranium; water chemistry; water pollution; China; Guangdong
Type
journal article