Spatial distribution of mercury deposition fluxes in Wanshan Hg mining area, Guizhou province, China

Abstract

Abstract. The legacy of long-term mining activities in Wanshan mercury (Hg) mining area (WMMA), Guizhou, China including a series of environmental issues related to Hg pollution. The spatial distribution of gaseous elemental mercury (Hg 0 ) concentrations in ambient air were monitored using a mobile RA-915 + Zeeman Mercury Analyzer during daytime and night time in May 2010. The data imply that calcines and mine wastes piles located at Dashuixi and on-going artisanal Hg mining activities at Supeng were major sources of atmospheric mercury in WMMA. For a full year (May 2010 to May 2011), sampling of precipitation and throughfall were conducted on a weekly basis at three sites (Shenchong, Dashuixi, and Supeng) within WMMA. Hg in deposition was characterized by analysis of total Hg (THg) and dissolved Hg (DHg) concentrations. The corresponding data exhibit a high degree of variability, both temporarily and spatially. The volume-weighted mean THg concentrations in precipitation and throughfall samples were 502.6 ng l −1 and 977.8 ng l −1 at Shenchong, 814.1 ng l −1 and 3392.1 ng l −1 at Dashuixi, 7490.1 ng l −1 and 9641.5 ng l −1 at Supeng, respectively. THg was enhanced in throughfall compared to wet deposition samples by up to a factor of 7. The annual wet Hg deposition fluxes were 29.1, 68.8 and 593.1 µg m −2 yr −1 at Shenchong, Dashuixi and Supeng, respectively, while the annual dry Hg deposition fluxes were estimated to be 378.9, 2613.6 and 6178 µg m −2 yr −1 at these sites, respectively. Dry deposition played a dominant role in total atmospheric Hg deposition in WMMA since the dry deposition fluxes were 10.4-37.9 times higher than the wet deposition fluxes during the whole sample period. Our data showed that air deposition was still an important pathway of Hg contamination to the local environment in WMMA.

Mercury Exposure in Children of the Wanshan Mercury Mining Area, Guizhou, China

“…The same tendency was also observed in soil, river sediment and rice cultivated in this area [24,35,45,46]. The THg concentrations of the samples were inversely proportional to their distance from the mine waste.…”

A compilation of field surveys on gaseous elemental mercury (GEM) from contrasting environmental settings in Europe, South America, South Africa and China: separating fads from facts

“…It is the area of severe Hg pollution due to Hg mining and smelting. Large-scale Hg mining operations stopped in 2004, while some artisanal smelting and mining activities are still present (Dai et al 2012). Air Hg concentration range reported for area (Dai et al 2012) covers the range between 17 and 2,100 ng m -3 ; however, in vicinity of abandoned and ongoing artisanal smelting activities, concentrations were much higher, exceeding locally few tens of lg m -3 (May 2011).…”

Atmospheric Mercury in China Studied with Differential Absorption Lidar

“…Particularly polluted areas are found in connection to the mining areas in the Guizhou province, in particular in the mercury mining areas in Wanshan [10,11]. Although official mining has been closed down in 2002, artisanal mercury extraction from the cinnabar ore in still ingoing, and there are large deposits of roasted ore, still containing high concentrations of metal mercury.…”