Aarhus Universitets segl

No. 812: Environmental monitoring at the cryolite mine in Ivittuut, South Greenland, in 2010.

Johansen, P., Asmund, G., Rigét, F. & Schledermann, H. 2010: Environmental monitoring at the cryolite mine in Ivittuut, South Greenland, in 2010. National Environmental Research Institute, Aarhus University. 34 pp. – NERI Technical Report No. 812.  

Summary

In Ivittuut at Arsuk Fjord in South Greenland the mineral cryolite was mined, sorted and shipped out from 1854 to 1987. The mining operations have caused pollution with lead and zinc in the fjord. The main source is waste rock, which has been left at the coastline and is still releasing lead and zinc to the fjord from tidal water action.

The pollution of the fjord has been monitored since 1982. Since 1985 this monitoring has included only brown seaweed and blue mussels, since earlier studies had shown that fish and prawns from the fjord did not have elevated lead and zinc levels. This report presents the results of the latest environmental study, which was carried out in July 2010.

The geographical pattern of lead and zinc levels found in brown seaweed and blue mussels in 2010 shows that waste rock deposited at the coastline in Ivittuut is still the main source of the pollution of the fjord.

In brown seaweed elevated lead levels were found on a c. 4 km stretch of coastline in eastern Arsuk Fjord around Ivittuut, whereas zinc levels were elevated on most of the coastline studied in Arsuk Fjord. In blue mussels elevated lead levels were seen in all of the studied parts of Arsuk Fjord, and also on coasts 3-4 km outside the fjord. Zinc levels in blue mussels were elevated only at Ivittuut.

Along a stretch of coastline of c. 5 km around Ivittuut the lead concentration in blue mussels is so high that it is recommended not to eat blue mussels from this area. This area is similar to that found in 2007, but smaller than found in 2004 and much smaller than found in the period 1982-1992. During that period it also included part of the western coastline of Arsuk Fjord.

Over the entire monitoring period (1982 to 2010) a decline of lead levels is seen in both brown seaweed and blue mussels in Arsuk Fjord. Lead concentrations have decreased c. 3 times since 1982. Zinc concentrations have also generally decreased, but at a slower rate.

Full report in PDF-format (2,98 MB)