[en] The project of high-level radioactive waste disposal is in the stage of site selection in Japan, and the site-specific performance assessment using the methodology of site-generic study has been developed after the publication of the second progress report (H12). In the same way, biosphere assessment using the behavior of radionuclides, which depends on the site-specific condition, has been started. As the beginning of development of biosphere modeling for HLW disposal founded on the environment of aquifer and biosphere that is the effluent region of radionuclides from natural barrier (surface and near-surface environment), we did examination of the surface and near-surface hydrological analysis, which is the hydrological and transport analysis in surface and near-surface environment for being used in biosphere assessment. This study specially focuses on groundwater flow in aquifer of surface and near-surface environment. Because no example of the surface and near-surface hydrological analysis, which is for biosphere assessment, in Japan, the purpose of this study is to understand the existing valuable skills and future issues in the implementation of the analysis. The issues have been addressed in this study are the following: (1) Survey of the foreign literature relating to the surface and near-surface hydrological analysis. (2) Survey of the domestic literature of groundwater flow and transport useful for the analysis. (3) Trial of transport analysis in surface and near-surface environment of the model site. (4) The setting and boundary conditions of model used for the surface and near-surface hydrological analysis. About the first issue, from literature of Sweden, we studied the calculation of the dose with account to radionuclides migration in the Quaternary, the influence of repository depth on the migration. Concerning the second item, collecting and compiling the useful information for the surface and near-surface hydrological analysis, which require the consideration of the vertical components of groundwater flow and large diversity of layers in surface and near-surface environment, from literature related to groundwater flow and pollution survey in Japan, we learned about the environmental tracer method, the permeability estimation method using unconfined groundwater level and so on. Concerning the third point, transport analysis in surface and near-surface environment using site-specific data for sensitivity analysis after this has been carried out to check out the influence of some parameters on transport phenomena, and the low sensitivities of the model area, permeability anisotropy to the concentration pattern and the relative high sensitivity of the difference of the source positions were shown. Concerning the fourth item, we examined the setting and the boundary conditions of model whose outputs include groundwater flow and transport rate into river, lake, sea. These outputs are used as inputs of biosphere assessment model. (author)