Author 1:
Name & Surname: Savelieva E. A.
Company: Institute of Problems of Safe Nuclear Power Development, Russian Academy of Sciences
Work Position: Head of Laboratory, Senior Researcher
Scientific Degree: Candidate of Physico-Mathematical Sciences
Contacts: esav@ibrae.ac.ru

Author 2:
Name & Surname: Suskin V. V.
Company: Institute of Problems of Safe Nuclear Power, Russian Academy of Sciences
Work Position: Engineer-Researcher

Author 3:
Name & Surname: Rastorguev A. V.
Company: Institute of Problems of Safe Nuclear Power, Russian Academy of Sciences
Work Position: Senior Researcher
Scientific Degree: Candidate of Engineering Sciences

Author 4:
Name & Surname: Ponizov A. V.
Company: Zheleznogorsk Division, National Operator for Radioactive Waste Management (NO RAO), Krasnoyarsk Territory
Work Position: Director

The presented research is concerned with a series of estimates made to determine applicability of a structure of stratified sedimentary rocks for long-term disposal and safe isolation of liquid radioactive waste. This paper offers two new approaches to parametrization of geo-percolation model to correctly account for heterogeneity of properties of geological medium. In the offered approaches, the heterogeneity of properties is modeled using lithologic heterogeneities of hydrogeological layers in a bed of sedimentation. The both approaches use input data on distribution of lithologic types (hydrofacies) in drill wells and the pumping test data. This paper gives theoretical description of the proposed approaches and exemplifies their application. The first method is construction of a field of local effective permeability factors in cells of analysis grid for a geo-percolation model. The field is constructed based on interpolation of permeability factors at points with the known lithologic structure. The values at these points are assessed by the permeability factors of hydrofacies preliminary calibrated using the pumping test data. The second method constructs, vice versa, the field of hyrofacies first, based on the distribution of lithologic types in drill wells and then calibrates the permeability factors of hydrofacies. The construction of the field of hydrofacies uses the probabilistic classification method based on the kernel probability density estimate of a class (hydrofacies). This method enables natural incorporation of the model of hydrofacies into the process of automated calibration of parameters. The application of the method is discussed in terms of an artificial example and in the framework of parametrization of GEOPOLIS program designed for geo-percolation and geomigration modeling of deep geological repository for liquid radioactive waste—Severny test ground.

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