To understand the effect of thermal loading from HLW on the groundwater flow nearby, the coupling of TH in an equivalent porous medium is studied. Results indicate that under given conditions the alteration of groundwater flow by decay heat is localized phenomena. More comprehensive studies are underway for THM coupling.
Zum Verstandnis fur die Wirkung der thermischen Belastung von HLW in der Nahe von Grundwasserstrom, ist die Verbindung von TH in den entsprechenden porigen Medium erarbeitet. Die Ergebnisse zeigen, dass unter vorgegebenen Bedingungen die Anderung von Grundwasserstrom durch Zerfallwarme lokalisiert wird. Zusatzliche umfassende Arbeiten sind fur die THM Kupplung auf dem Wege.
Pour comprendre l'effet du chargement thermique de HLW sur l'ecoulement d'eaux souterraines tout près, l'accouplement du TH dans un milieu poreux equivalent est etudie. Les resultats indiquent que dans des conditions donnees le changement d'ecoulement d'eaux souterraines par la chaleur d'affaiblissement est des phenomènes localises. Des etudes plus complètes sont en cours pour l'accouplement de THM.
The Republic of Korea is strongly dependent upon nuclear energy. By the year 2015, 28 nuclear power plants are to be in operation. While nuclear power plants continuously supply electricity with high capacities and without any significant operational disruption, the problem of radioactive waste disposal has been a major national concern. Korea Atomic Energy Research Institute (KAERI) has initiated the basic research and development (R&D) program on the permanent disposal of high level radioactive wastes [Hwang 2003] which are currently composed of PWR and CANDU spent fuels. One of the tasks in the R&D on the disposal of HLW is to understand the groundwater flow and associated radionuclide transport from a proposed repository to an accessible biosphere. It has been widely argued whether the decay heat affects the safety of a repository. To study it, three deposition holes are proposed to locate 50 meters below from the surface as a part of validation exercise [Hwang 1997]. The construction of the validation tunnel will be started from the middle of 2004.
After the excavation of the tunnel, surface mapping inside the tunnel shall be performed. Results from this survey shall then be compared with the borehole data from the detailed site investigation. The detailed site investigation is planned to start in 2003. To understand groundwater flow through fracture networks around a deposition hole to be built after 2007, small diameter boreholes shall be drilled at the location of proposed locations for deposition holes. Insitu data such as fracture network and the rates of incoming flow into the boreholes shall be measured. After completion of this job, deposition holes with around 1.5 m diameters shall be excavated by the small scale raising boring machine and the data shall be acquired from the deposition holes. Then the measured data shall be compared with the data from the previous borehole experiments. This comparison shall be expected to help us understand methodology to identify the fracture network data, importance of the channeling, and importance of the excavation disturbed zone on the ground water flow.