First day in the tunnel

Tuesday 20th March. Posted by Miriam Jackson

After a good nights sleep in the tunnel, we woke up ready to work on our long list of projects. We had breakfast and then put on our helmets and headlamps, that we wear all the time in the tunnel, and walked the 1.5 km from the living quarters to the laboratory area.

On the way to the laboratory area we stopped at the sediment chamber, where the sediment from the tunnel system settles out to be flushed out once a year, and downloaded data from a hydrological station there. We also had to the read the scale to make sure that the data are correct.

The main job for two of us this morning was to download data from other hydrological stations that are a little harder to reach. They are in a tunnel called Fonndalstunnel that runs underneath the whole of Engabreen and even further to the next valley. We had hoped to download the data on a previous trip last November, but at that time there was an abnormally high discharge in the tunnel due to very heavy rains, and we had to postpone the data collection.

This time there was much less water, but even so, the water is very deep in places and it is necessary to wear waders. I had gone only a short distance when I realised with dismay that my waders had a slow leak in the boots, and I then spent the next two hours with with my feet sloshing around in ice cold water. We passed an ice plug on the way, where there is an intake to capture water into the tunnel system, but where the ice squeezes through in the wintertime.

After a while the water wasn’t quite as deep and walking wasn’t such hard work. In some places in the tunnel it’s even possible to walk along rocks, and although uneven, it’s much easier going. The tunnel widens slightly in a couple of places, and here there tends to be small accumulations of sand at the side. I often think that these beaches would be an ideal place for a holiday – no crowds, guaranteed no rain and a lovely sand at the side of the river. The lack of sunshine in the tunnel may be a problem for some people, though .....

After about 40 minutes we reached the first hydrological station. It took just a few minutes to download several months of data, and to manually read the scale. The next station is only a few hundred metres farther through quite shallow water. After we have got the data from both stations we turned around for the slow walk back. The whole trip took more than two hours. It’s not until I took off my waders that I realised how wet I had become. Fortunately Coline picked a better pair of waders and was as dry as a bone.

After eating lunch, which partly became a game of dare as some people ate the mackerel in tomato and others refused to try it, we continued work on our various tasks. Mathieu is working on how to use a Kinect (usually used for playing games with an xbox) to measure the topography underneath the ice.

Coline helped the American group to re-mount their seismometers that they use for measuring the very small earthquakes created as the glacier moves. Pierre-Marie and I got equipment ready for doing pump tests under the glacier (pumping water under the glacier to see how it reacts) and for other experiments he hopes to do over the next few days including measuring how fast the ice is sliding.

The Americans were responsible for cooking the evening meal and one of them is worried because he has made too much food and thinks it will be wasted. However, he had underestimated the appetites of hungry scientists and the food is soon all gone. Our first full day in the tunnel has been productive and everyone feels they are making good progress.

Miriam

Photo 1: The students are ready to start working in the tunnel.

Photo 2: Coline Mollaret makes measurements inside the ice.