Site investigation equipment developed by Teollisuuden Voima Oy

The preliminary site investigations for the final disposal of HLW produced by TVO were started in 1987. The investigations have been carried out in five canditate areas. As a preparation in 1983 TVO sounded out the investigation resources available in Finland by means of an inquiry. Special emphasis was laid on methods involving 56 mm boreholes of great depth. The results indicated that crucial investigation equipment were not available in Finland, and neither were it certain that those could be acquired from abroad. This gave an impetus for the development work of instruments for groundwater sampling, hydraulic head monitoring, hydraulic conductivity and direct groundwater flow measurements. This paper briefly presents aforementioned equipment, experiences from their use and some results