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No. 319: Environmental monitoring at the former Seqi olivine mine in Southwest Greenland 2011-2018

Søndergaard, J. (2019). Environmental monitoring at the former Seqi olivine mine, in Southwest Greenland 2011-2018. Aarhus University, DCE – Danish Centre for Environment and Energy, 36 pp. Scientific Report No. 319 http://dce2.au.dk/pub/SR319.pdf

Summary

The Swedish mining company Minelco A/S (formerly Seqi Olivine A/S) was in 2005 granted permission to exploit the industry mineral olivine at Seqi in Niaqunngunaq (Fiskefjord) in Southwest Greenland. After initial test work and construction in late 2005 and 2006, the production began in spring 2007. In late 2009, the mining was stopped due to economic reasons and the mine site closed.

Since 2004, environmental studies have been conducted at Seqi almost every year to monitor the environmental impact from mining during and after the mining operation. In this report, the results from the sampling campaign from 2011 to 2018 are presented and discussed. The sampling programme included lichens, seaweed and blue mussels, which serve as key monitoring species in terrestrial and marine environments, respectively, supplemented with surface soil and fresh water samples during the latest sampling in 2018.

In the terrestrial environment, results from collection and analyses of lichens showed that concentrations of mine-related contaminants, mainly chromium (Cr), iron (Fe), cobalt (Co) and nickel (Ni), had decreased since the mining period. During the last year of the monitoring, 2018, the concentrations had decreased to baseline levels more than 1 km away from the mining area. Within 1 km of the mine pit/former ore crusher site, slightly elevated contaminant concentrations were observed in lichens during the entire period. The results indicate that dust dispersion and deposition from the mine have decreased markedly since the mine closure. There is still (2018) some minor dust dispersion and deposition within a 1 km area of the mine, highest in immediate vicinity to the mine pit.

In the marine environment, collection of seaweed and blue mussels showed that the concentrations of the main contaminants Cr and Ni had decreased to background level in 2018 at all stations. This indicates that dispersion of both dissolved and particle-bound metals from the mining area into the marine environment at Seqi, as measured during the latest sampling in 2018, is negligible.

In conclusion, the monitoring campaign showed that the concentrations of contaminants in both the terrestrial and marine environment had decreased since the mining activities stopped in 2009. Only slightly elevated levels of Cr and Ni could be measured in the terrestrial environment within 1 km from the mine during the latest sampling event and not in the marine environment. Consequently, DCE assesses the current environmental impact from the mining activities at Seqi as insignificant to the environment at Seqi.

This report finishes the planned environmental studies at Seqi after mine closure. Based on the conclusions above, DCE assesses that further studies are not required at this stage. However, in case the pier is to be removed at some point in the future, additional environmental studies may be required to evaluate the potential effects of this. Overall, DCE regards the olivine mine at Seqi as an example of how a mine can be operated in Greenland with minimum environmental impact by establishing adequate environmental requirements and conditions as part of the license and through detailed environmental monitoring and regulation during mine operation.