FATE OF MERCURY IN THE ARCTIC Michael Evan ... - COGCI

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Frozen slices are sub-sampled uniformly with a hand-operated stainless steel (AISI
304) press, which recovers volumetric plugs for further analysis (Fig. 5). These plugs are then used
as is for measurements of physical properties such as moisture content and bulk density, and for
recovering plant macrofossils for 14 C age dating. Plugs can also be dried and milled to provide a
homogeneous fine powder for subsequent chemical analyses, and for 210 Pb age dating.
FIELD WORK
The Environmental Chemistry Research Group at the University of Southern
Denmark, in collaboration with Institute for Environmental Geochemistry at the University of
Heidelberg, the Danish National Environmental Research Institute, the University of Berne, and the
Geological Survey of Denmark and Greenland (GEUS), are investigating long-term records of
contaminants (Hg, Cd, Pb and polycyclic aromatic hydrocarbons (PAHs)) in the Arctic, using
permanently frozen peat deposits as environmental archives. The sites chosen to date are on
Bathurst Island, Nunavut, Canada and Nordvestø, Carey Islands, Greenland, based on previous
investigations at the sites by the Geological Survey of Canada (GSC) undertaken approximately 30-
40 years ago (Blake 1964, 1974, 1977,1978,1982). The verified stratigraphy, physical and
palynological determinations in the peat deposits made the sites prudent candidates for the present
study, as did the advice offered by Dr. Weston Blake Jr. with respect to the sites and coring
experiences. The excellent field descriptions provided by Dr. Blake enabled us to return to the exact
sites where he cored and actually find the still-capped boreholes left after his investigations on
Nordvestø and near his site at Bracebridge Inlet. By sampling at or near the previous sites, we were
able to obtain samples that provide supplementary and complementary information to those taken
for the previous studies.
CONCLUSION
Our sampling system is the result of laboratory testing prior to our Bathurst Island
campaign during the summer of 2000, field-testing on Bathurst Island, subsequent improvements