Projects
Airborne Measurements:
Surveying of nuclear installations in Switzerland by means of aeroradiometrics started in 1989. First the areas around the nuclear power stations (Mühleberg, Gösgen, Beznau, Leibstadt) and the PSI in Würenlingen about 50 km2 each were measured once a year on behalf of the HSK. These measurements are performed biannually for a given site since 1994. The goal of these measurements is on the one hand to monitor the nuclear power plants, on the other hand to get base-line information for the surroundings. These measurement flights once a year serve also as training and show whether the instruments are working reliably.
In geological mapping the aeroradiometric method gives a possibility to distinguish between geological formations with different natural radioisotope content. Aeroradiometrics in Switzerland started with such a project of the Swiss Geophysical Commission in the year 1986. Within the scope of this project, the alpine Central Massifs have been investigated and mapped by aeroradiometrics. Because these annual flights are limited, it is not possible to do extensive mearurements for geological mapping. Nevertheless, some radiometrically interesting areas are measured during the annual flights. Besides the mapping of natural radioisotopes it is also possible to identify artificial radioisotopes. Further, mapping of the caesium-fallout connected with the release from the Tchernobyl nuclear power plant has been done to find possible hot-spots.
To be able to cooperate internationally in case of a nuclear accident, several intercalibration fligths with teams of other countries have been done and will be done. A common flight with the French CEA team was done in 1995. In the year 1997 we did a common flight with the team of the Austrian Geological Survey in the Austrian Alps and with the German team from the Bundesamt für Strahlenschutz (BfS) in 1999 in the Black Forest area. During the annual survey 2001 two profiles (one in North-South direction, another in East-West direction) across Switzerland were carried out. In May 2002 an inernational exercise was held in SW Scotland. This exercise was part of the ECCOMAGS project, a project of the European Commission. Unfortunately several teams were not allowed to fly and to carry out the planned measurements.
2007 a common exercise with the French (CEA) and German (BfS) team were held in Switzerland. Beside intercalibration measurements around the NPPs Gösgen and Mühleberg and a search for orphan sources the highlight was a composite mapping exercise around the citiy of Basel. In 2009 a similar exercise organised by the German team from BfS took place near Munich. Because of bad weather conditions not all tasks could be carried out.
International Cooperation:
In addition to the intercalibration flights with teams from the neighbouring countries, cooperation with other countries and teams is pursued. A better cooperation was expected by the EU-project ECEAGS (European Coordination of Environmental Airborne Gamma Spectrometry). The goal of this project was on the one hand to collate the state of the art in the field of aeroradiometrics in the different countries and on the other hand to define a first, rough international standard for mapping and reporting. In this project different working groups worked on specific subjects of aeroradiometrics. The project ECCOMAGS which followed the ECEAGS program wanted to prove the calibration of equipment of the different European teams. So an international exercise was organized but unfortunately just one half of the teams could carry out measurements. The other teams were not allowed to fly and to take measurements. In 2003 a common exercise with Austria took place in Kaernten/A. In 2007 a common exercise with Germany and France was organized in Switzerland. One of the tasks was the composite mapping of the region around Basel. In 2009 a similar exercise with the same participants took place near Munich. Near Chemnitz in 2015 the exercise AGC15 took place with teams from Germany, France, Czech Republic and Switzerland. 2017 teams from the same countries met in Dübendorf/Switzerland for the exercise ARM17.