8/4/2017

Preliminary investigations for hydroelectric plant in South Greenland

By Geo Communication

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From mid-August to mid-September Geo performs preliminary investigations for a dam in relation to an expansion of the hydroelectric plant Qorlortorsuaq in South Greenland. The expansion will allow the plant to double the energy potential.

The purpose is a greener Greenland. The means to achieve this is to reduce the oil consumption and expand Greenland’s hydroelectric plants. The hydroelectric plant Qorlortorsuaq supplies the towns of Qaqortoq and Narsaq with electricity. In Qaqortoq the hydroelectric power is also used for electric heating. If the project is realised, the plan is to expand the hydroelectric power for electric heating to Narsaq, in order to supply both towns and the 4700 inhabitants with power and electric heating.

The expansion of the plant will double the energy production and ensure that the heating demand in Qaqortoq and Narsaq is met, in order to decrease the oil consumption for heat production.

 

Complex underground and logistics

In order to investigate the soil conditions, where the dam is planned to be located, Geo will perform geotechnical borings with sampling and in-situ tests. In addition to this, the borings will be screened and geophysical flow-logging and pump tests in selected borings will be performed, in order to determine the permeability coefficients to assess the density of the sediment layers and to assess the need for further sealing.

When drilling in a partially dry riverbed, it is crucial to have the right equipment at hand, due to a complex subsurface with soil layers shifting between clay, silt, sand, gravel and rock. However, bringing the right drilling equipment to the site is one of the biggest challenges, when working in Greenland. In addition, the investigations are carried out in a highly inaccessible area, why the logistics is a discipline in itself.

 

Drill rig goes airborne

The drill location is secluded in a most rugged terrain, eliminating traditional transport by car or lorry. Therefore, the drilling equipment, drill rig and camp facilities are transported by ship to a small nearby harbour from where equipment, drill rig and camp facilities are flown by helicopter the remaining 20 km to the drill site. A camp is set up for Geo’s drillers near the drill site to avoid delays caused by transport challenges or bad weather. Because of the nearby glacier/ Inland ice foehn winds with wind speeds up to 50 m/s add an additional layer of challenges to the overall difficult conditions.

It’s Greenland’s energy supply Nukissiorfiit in close collaboration with the client consultant NIRAS that has requested Geo for the preliminary investigations.

Preliminary investigations in Greenland.