| Title | Comparison of mercury and zinc profiles in peat and lake sediment archives with historical changes in emissions from the Flin Flon metal smelter, Manitoba, Canada |
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| Author | Outridge, P M ;
Rausch, N; Percival, J B; Shotyk, W; McNeely, R |
| Source | Science of the Total Environment vol. 409, 2011 p. 548-563, https://doi.org/10.1016/j.scitotenv.2010.10.041 |
| Image |  |
| Year | 2011 |
| Alt Series | Earth Sciences Sector, Contribution Series 20100052 |
| Publisher | Elsevier BV |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Manitoba |
| NTS | 63K/12; 63K/13; 63L/09; 63L/10; 63L/15; 63L/16; 63M/01; 63M/02; 63M/07; 63M/08; 63N/04; 63N/05 |
| Area | Flin Flon |
| Lat/Long WENS | -103.0000 -101.5000 55.5000 54.5000 |
| Subjects | environmental geology; smelters; environmental analysis; environmental impacts; pollutants; zinc; mercury; peat; peat samples; peat geochemistry; lake sediment geochemistry; lake sediments |
| Illustrations | location maps; profiles |
| Program | Environmental Geoscience |
| Released | 2011 01 01 |
| Abstract | The copper–zinc smelter at Flin Flon, Manitoba, was historically the largest single Hg point-source in Canada, as well as a major source of Zn. Although emissions were reported by industry to have
declined significantly since the late 1980s, these reductions have never been independently verified. Here, the histories of Hg and Zn deposition over the past century or more were determined at five lake sediment and three peat study sites in the
surrounding region. At sites spanning the range from heavy to minor pollution, lake sediment Hg and Zn concentration and flux profiles increased significantly in the early 1930s after the smelter opened. Two of the three peat archives were wholly or
partially compromised by either physical disturbances or biogeochemical transitions which reduced their effectiveness as atmospheric metal deposition recorders. But the remaining peat records, including a detailed recent 20 yr record at a moderately
polluted site, appeared to show that substantive reductions in metal levels had occurred after the late 1980s, coincident with the reported emission reductions. However, the lake sediment results, taken at face value, contradicted the peat results in
that no major declines in metal concentrations or fluxes occurred over recent decades. Mercury and Zn fluxes have in fact increased substantially since 1988 in most lakes. We suggest that this discrepancy may be explained by catchment soil saturation
by historically deposited metals which are now mobilizing and leaching into lakes, as has been reported from other smelter polluted systems in Canada, whereas the upper sections of the peat cores reflected recent declines in atmospheric deposition.
However, further research including instrumented wet and dry deposition measurements and catchment/lake mass balance studies is recommended to test this hypothesis, and to provide definitive data on current atmospheric metal deposition rates in the
area. |
| GEOSCAN ID | 285384 |
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