TY - JOUR

T1 - Bacterial and chemical oxidation of pyritic mine tailings at low temperatures

AU - Elberling, Bo

AU - Schippers, Axel

AU - Sand, Wolfgang

N1 - Funding Information: This study is part of the MIKA-project “Chemical fluxes in frozen soil” funded by the Environmental Department, Ministry of Environment and Energy (Denmark). The project is supported by National Environmental Research Institute, Institute of Geography (University of Copenhagen) and Nanisivik Mine. Many thanks to T.B. Zunic for help with the X-ray measurements and to K. LeDrew and J. Goyman, Nanisivik Mine for help, access to data, and hospitality. A.S. was funded by contract No. 1490954 to W.S. from the German BMBF via Umweltbundesamt. Also thanks to anonymous reviewers for many helpful comments on the manuscript.

PY - 2000/2/15

Y1 - 2000/2/15

N2 - Microbial and chemical sulfide oxidation activity and oxygen consumption was investigated in the active layer of pyritic mine tailings at Nanisivik Mine, located in a permafrost area on Baffin Island in northern Canada. Samples of tailings were collected up to a depth of 60 cm in mid-August 1998 at 4 sites, for which the metabolic activity of sulfur- and iron-oxidizing leaching bacteria besides the chemical pyrite oxidation activity were measured on 39 tailings samples and 7 samples from a natural pyritic site by calorimetry. The tailings of varying age and water content were deposited under alkaline conditions. In situ oxygen uptake rates were measured at the tailings surface every third day, prior to sampling. In addition, cell counts of iron(II), sulfur, and thiosulfate oxidizing, lithotrophic bacteria and chemoorganotrophic microorganisms were determined quantitatively by the most- probable-number technique or by agar-plating. Results show consistent pyrite oxidation rates based on in situ oxygen uptake rates, and laboratory heat output measurements. Litho- and organotrophic bacteria were found in the tailings. Calorimetric measurements revealed that the present bacterial activity is responsible for approximately one third of the ongoing oxidation. Although leaching bacteria have previously been found in the Arctic, this study is the first to prove the significance of bacterial activity in the overall pollution resulting from tailings deposited in the Arctic.

AB - Microbial and chemical sulfide oxidation activity and oxygen consumption was investigated in the active layer of pyritic mine tailings at Nanisivik Mine, located in a permafrost area on Baffin Island in northern Canada. Samples of tailings were collected up to a depth of 60 cm in mid-August 1998 at 4 sites, for which the metabolic activity of sulfur- and iron-oxidizing leaching bacteria besides the chemical pyrite oxidation activity were measured on 39 tailings samples and 7 samples from a natural pyritic site by calorimetry. The tailings of varying age and water content were deposited under alkaline conditions. In situ oxygen uptake rates were measured at the tailings surface every third day, prior to sampling. In addition, cell counts of iron(II), sulfur, and thiosulfate oxidizing, lithotrophic bacteria and chemoorganotrophic microorganisms were determined quantitatively by the most- probable-number technique or by agar-plating. Results show consistent pyrite oxidation rates based on in situ oxygen uptake rates, and laboratory heat output measurements. Litho- and organotrophic bacteria were found in the tailings. Calorimetric measurements revealed that the present bacterial activity is responsible for approximately one third of the ongoing oxidation. Although leaching bacteria have previously been found in the Arctic, this study is the first to prove the significance of bacterial activity in the overall pollution resulting from tailings deposited in the Arctic.

KW - High Arctic

KW - Microbial activity

KW - Oxygen

KW - Pyrite oxidation

UR - http://www.scopus.com/inward/record.url?scp=0033989468&partnerID=8YFLogxK

U2 - 10.1016/S0169-7722(99)00085-6

DO - 10.1016/S0169-7722(99)00085-6

M3 - Journal article

AN - SCOPUS:0033989468

VL - 41

SP - 225

EP - 238

JO - Journal of Contaminant Hydrology

JF - Journal of Contaminant Hydrology

SN - 0169-7722

IS - 3-4

ER -