20 old drillings were sealed at Radiana site in June and July 2015. The total length of the drillings was 850 m. This group of wells was drilled in the period 2008-2011. They were used for survey and characterization of the terrain during the site selection period. The sealing of the old drillings was implemented with the use of special technology of the consortium between Nuclear National Laboratory, a company which operates mainly in UK and North and South America and performs hydro-geological monitoring related mainly to the construction of similar depositories, Deconta – a Czech company with experience in East Europe and Asia which main activity is discovery and monitoring of contaminated areas, and British Geological Survey. The consortium works with a Bulgarian subcontractor.
Peter Hiller, Technical Project Manager explained that the objective of the reliable sealing of the historic drillings was to avoid underground water bodies, to prevent migration of pollutants from the surface to the underground waters. A new drilling is to be constructed which will be connected to the system of already existing 12 new drillings. Samples will be taken from them and analysed on quarterly basis which will verify and supplement the information collected from the previous monitoring drillings.