The water supply to Longyearbyen:
A snow survey in Gruvedalen
The valley supplies drinking water to Longyearbyen during summer and its primary water source is snowmlet from snow that was deposited the previous winter. Therefore, measurements of snow accumulation and the volume of snow available for melt throughout the melt season are important for the Lokalstyre.
Hydrology in Gruvedalen
Monitoring of summer meltwaters from the beginning of snowmelt (5th June) until cessation of icemelt and significant decrease in water discharge (30th August) is performed to establish seasonal changes in a broad range of water quality parameters (such as pH, dissolved ions, nutrients and contaminant metals).
River monitoring station installed at the water intake pipe collects hourly records of river runoff, electrical conductivity and water temperature. Knowing those variables allows for quantification of total freshwater discharged from the valley as well as continuous monitoring of water quality.
Hydrochemistry in Gruvedalen
The results indicate the influence of acid mine drainage on drinking water supply to Longyearbyen.
Gruvedalen, waters are concentrated in heavy metals derived from waste rock, but the reactions do not produce water quality issues to the same extent as seen in waste rock effluent in Bjørndalen, and in certain parts of Longyeardalen.
The poor water quality can be expected at the beginning and at the end of summer.
In the first case, contaminants are leached from both the snowpack and the underlying mine waste rock.
The high concentrations at the end of summer, are caused by low discharge and high duration of rock-water contact. Furthermore, there is no dilution of the seepages from hillslopes surrounding the mine