Effects of acid-sulfate weathering and cyanide-containing gold tailings on the transport and fate of mercury and other metals in Gossan Creek: Murray Brook mine,New Brunswick,Canada |
| |
| Institution: | 1. Department of Geology and The Canadian Rivers Institute, University of New Brunswick, Fredericton, New Brunswick, Canada E3B 5A3;2. Department of Geosciences, University of Texas at Dallas, Box 830688 Richardson, TX 75083-0688, USA;3. Department of Civil Engineering and The Canadian Rivers Institute, University of New Brunswick, Fredericton, New Brunswick, Canada E3B 5A3;4. Fisheries and Oceans Canada, Marine Chemistry Section, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada B2Y 4A2;5. New Brunswick Department of Environment and Local Government, Marysville Place 20 McGloin Street, Fredericton, New Brunswick, Canada E3A 5T8;1. State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, China;2. State Key Laboratory of Solid Waste Reuse for Building Materials, Beijing Building Materials Academy of Sciences Research, Beijing 100041, China;1. Environmental Biotechnology Department, Faculty of Power and Environmental Engineering, Silesian University of Technology, ul. Akademicka 2, PL-44 100 Gliwice, Poland;2. Ecole Nationale Supérieure des Mines, GéoSciences & Environnement Département, CNRS:UMR 5600, EVS;158, cours Fauriel, F-42023 Saint-Etienne Cedex 2, France;1. Dipartimento di Fisica dell’Università di Genova and CNR-IMEM, Via Dodecaneso 33, 16146 Genova, Italy;2. Dipartimento di Fisica dell’Università di Genova and INFN, Via Dodecaneso 33, 16146 Genova, Italy |
| |
| Abstract: | Gossan Creek, a headwater stream in the SE Upsalquitch River watershed in New Brunswick, Canada, contains elevated concentrations of total Hg (HgT up to 60 μg/L). Aqueous geochemical investigations of the shallow groundwater at the headwaters of the creek confirm that the source of Hg is a contaminated groundwater plume (neutral pH with Hg and Cl concentrations up to 150 μg/L and 20 mg/L, respectively), originating from the Murray Brook mine tailings, that discharges at the headwaters of the creek. The discharge area of the contaminant plume was partially delineated based on elevated pH and Cl concentrations in the groundwater. The local groundwater outside of the plume contains much lower concentrations of Hg and Cl (<0.1 μg/L and 3.8 mg/L, respectively) and displays the chemical characteristics of an acid-sulfate weathering system, with low pH (4.1–5.5) and elevated concentrations of Cu, Zn, Pb and SO4 (up to 5400 μg Cu/L, 8700 μg Zn/L, 70 μg Pb/L and 330 mg SO4/L), derived from oxidation of sulfide minerals in the Murray Brook volcanogenic massive sulfide deposit and surrounding bedrock. The HgT mass loads measured at various hydrologic control points along the stream system indicate that 95–99% of the dissolved HgT is attenuated in the first 3–4 km from the source. Analyses of creek bed sediments for Au, Ag, Cu, Zn, Pb and Hg indicate that these metals have partitioned strongly to the sediments. Mineralogical investigations of the contaminated sediments using analytical scanning electron microscopy (SEM), transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM), reveal discrete particles (<1–2 μm) of metacinnabar (HgS), mixed Au–Ag–Hg amalgam, Cu sulfide and Ag sulfide. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
