Estimation of nonuniformity in characteristics of strong rock masses for radioactive waste disposal

Safe disposal of radioactive waste is one of the challenging problems which define the scale and dynamics of the nuclear industry. Currently, the world scientific community has recognized that the safest solution to the problem of final isolation of high-level and long-lived radioactive waste is the waste disposal in rock mass at the depths not less than 300–500 m. In this case, as critical aspect of validation of radioactive waste disposal safety is prediction of radionuclides in geological environment. The most probable mechanism of potential egress a radioactive pollutant beyond the boundaries of its burial in strong rock masses is their transport with groundwater along the systems of fractures. Strong rock masses feature much higher anisotropy of the water-transmitting capabilities as compared with porous media, and super low values of permeability, which complicates its evaluation and adds up the difficulty of predictive hydrogeological calculations during validation of long-term safety of deep waste disposal. These arguments set the priority of finding methods for water transmissivity evaluation in strong rock masses, in the areas planned for the arrangement of underground research laboratories for deep radioactive waste disposals. This article describes a computational method to determine the fracture conductivity tensor and its components, which enables evaluating nonuniformity of water transmissivity in jointed areas of solid rock masses using the input data on the quantitative variables of cracks from a set of borehole logging measurements.

Kazakov K. S. Estimation of nonuniformity in characteristics of strong rock masses for radioactive waste disposal. MIAB. Mining Inf. Anal. Bull. 2024;(3):42-54. [In Russ]. DOI: 10.25018/0236_1493_2024_3_0_42.

K.S. Kazakov, Deputy Chief of the Safety Justification Methodologies Laboratory, Nuclear Safety Institute of Russian Academy of Science (IBRAE RAS), 115191, Moscow, Russia, e-mail: kks@ibrae.ac.ru, ORCID ID: 0000-0001-6755-0021.

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