Design and Development of the Large Scale In-situ PRACLAY Heater Test and Horizontal HLW Disposal Gallery Seal Test in Belgian URL Hades

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In Belgium, the Boom Clay was selected as a potential host formation for the disposal of High Level Radioactive Waste (HLW). In order to demonstrate at large scale the suitability of the Boom Clay to undergo the thermal load induced by the HLW, a large scale in-situ heater test, called PRACLAY heater test will be conducted in the URL of Belgium. The Praclay gallery hosting the heater test leaves an opportunity to study the possibility to seal a disposal drift in Boom clay and to test the feasibility to cut-off hydraulically any preferential pathway to the main access gallery through the EDZ (Excavation Damage Zone) and the lining with a seal in a horizontal drift (horizontal seal). This paper provides detailed consideration on the Thermal-Hydro-Mechanical boundary conditions for the design of the Praclay heater and seal tests with the support of numerical scoping calculations. It is believed that these important items considered in the Praclay heater test design constitute also key issues for the repository design. The outcome of the Praclay heater test will be an important milestone for the Belgian repository design.


Original languageEnglish
Title of host publicationInternational Symposium on Unsaturated Soil Mechanics and Deep Geological Nuclear Waste Disposal (UNSAT-WASTE 2009)
Place of PublicationShanghai, China
Publication statusPublished - Dec 2009
EventInternational Symposium on Unsaturated Soil Mechanics and Deep Geological Disposal of Nuclear Waste Disposal - UNSAT-WASTE - jointly organised by " Institute of Rock and Soil mechanics, Chinese Academy of Science", "TongJi University" of China and “Ecole nationale des ponts et chaussées”, Shanghai, China
Duration: 24 Aug 200928 Aug 2009


ConferenceInternational Symposium on Unsaturated Soil Mechanics and Deep Geological Disposal of Nuclear Waste Disposal - UNSAT-WASTE


  • High Level Waste HLW, geological disposal facility, host formation, Boom clay, seal, heater test, EDZ, hydraulic cut-off, THM boundary conditions, scoping calculation, bentonite, swelling

ID: 374241