| Mineral bearing arsenic is commonly found in gold mine. Contamination caused by golden mining has been studied for several decades. Water is one of the main mediums and paths for arsenic to produce and release toxic effect on human. The toxicity of arsenic depends on its different species, generally speaking, inorganic states are more toxic than organic species. For inorganic species, As (III) is 50 times toxic than As(V). So researchers are very interested in As species in order to assess the environment quality or toxicity.For the contamination from golden mining, this study takes Yangshu Gold Mine as research area. It's located in Dandong, Liaoning province. In this paper, samples from surface water and groundwater were collected in both dry and wet season. The author conducted batch and column experiments in laboratory for studying the transport and adsorption capacity of different species arsenic, and forecast transport rules of arsenic in surface water.Firstly, the method of different species arsenic was studied by IC-HG-AFS(ion chromatography-hydrogen generation-atom fluorescence spectrometer). The detection limits of As(Ⅲ), As(Ⅴ), mono-methyl arsenic (MMA) and di-methyl arsenic (DMA) could be lowed 2.0μg /L,4μg /L,4μg /L and 4μg /L respectively. The relative standard deviation(RSD) of determination(n=7) was less 5%. At the mean time, the preservation experiment was done. The experiment data showed transform between As(Ⅲ) and As(Ⅴ) was effectively reduced when samples filtered by 0.45μm membrane were stored at 4℃because filtration and cold storage reduced amount and activity of microbe. Sorption of arsenic caused by Fe and Mn precipitation was cut down by adding EDTA or acid that makes pH≤2.Secondly,based on field survey in dry and wet season, Arsenic in aquatic environment comes from gold mining. The concentration of total arsenic is 3-20 times over surface water quality standard(Ⅲ). Arsenate and arsenite were found in surface water and groundwater, but no organic arsenic was identified.Compared to wet season, arsenic is difficult to mobile in dry season. Attenuation constant in dry season is 0.3082(1/km), but it is 0.0569(1/km)in wet season. If initial concentration of As was 500μg/L without other contamination source in down stream, arsenic would deceased to 50μg/L in down stream 7.5km in dry season but 40km in down stream 40km. As(Ⅴ) is dominate species in river running throμgh mining area. 90% of total arsenic is As(Ⅴ) in dry season, 78% in wet season. There were not any organic arsenic was found.Arsenic can be adsorped by sand medium form shallow aquifer which has stronger sorption for As(Ⅴ) than As(Ⅲ). Based on D-R(Dubinin-Radushkevich) equation, adsorption energy of 6 kinds of simulated water were obtained by batch eaperiments. As (Ⅲ) was oxidized to As(Ⅴ) quickly in column experiments. Adsorption of As on sand finished instantaneously and zero detention time rose with mobility distance. The sorption kinetic of arsenic on aquifer medium fits zero-order dynamics equation.
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