English to French Other Nuclear Eng/Sci Nuclear waste/Repository in mines

Bonjour à tous les experts :)))) Je traduis un avis d'expert relatif à la fermeture des mines de potasse et au confinement / à l'extraction des déchets nucléaires entreposés dans ces mines. J'ai un problème avec le terme drift sealing dams. Merci pour votre aide et pour toutes les explications que vous pourrez me fournir.


Mines de Potasse d’Alsace (MDPA) is the operator of the StocaMine underground reposi-tory in the mine workings of the former Amelie Potash Mine at Wittelsheim, which was in operation until 2002. Around 42,000 metric tonnes of waste were deposited in the disposal blocks below the two (partly mined) potash seams "CS" and "CI". The mining operations and the ultimate waste storage were stopped in 2002.
At the initiative of MDPA, various studies were carried out on the geomechanical, hydro-geological and chemical aspects of the repository, but also on issues of waste retrieval, safe containment of the waste, general storage measures and measures to close off ac-cess drifts. As a result of these studies, boundary conditions for the closure of the under-ground repository were formulated. The technical concept developed against this back-ground for the safekeeping of the repository includes, among other things, filling the exist-ing cavity in the repository field within the scope of mine safety and technical possibilities by partial backfilling and sealing the access drifts to the repository field permanently using sealing dams with mass concrete sealing elements (brine concrete).
An essential boundary condition of the present safety concept is the fact that the locations of the drift-sealing dams will only be reached after several centuries due to the rising brine level in the mine according to updated flooding forecasts (CESAME, 2020, /4/). This means that the respective drift-sealing dam does not have to be fully effective immediate-ly, but, as a premise for the tight containment of the contaminants, credit is taken that the required integrity (tightness) of the sealing dams will set in over a period of several dec-ades after their completion as a result of the convergence of the adjacent rock (ARTELIA et al., 2016b,