Research of influence of various factors on repair-and-renewal operations in technological wells during uranium geotechnology in complex mining and geological conditions

Purpose. The research aims to improve the efficiency and reliability of repair-and-renewal operations in technological wells in complex mining and geological conditions involved in in-situ uranium leaching by identifying and analyzing the in-fluence of geological, geochemical and technical factors. Methods. The research is based on a comprehensive analysis of field data on well designs, rock characteristics and geochemical conditions of ore-bearing horizons. Filtration parameters, types of stripped rocks, composition of working solutions and peculiarities of well operation with different operating durations are analyzed. Statistical analysis methods, including correlation and regression analysis, are used to systematize the factors influencing the frequency and efficiency of repair activities. The results are compared with laboratory experiments that assess the effectiveness of various chemical reagents taking into account mineralogical-geochemical peculiarities of uranium ores. Findings. The conducted analysis makes it possible to determine that the intensity of repair-and-renewal operations is directly dependent on a combination of several factors, among which the most important are the geological structure of ore-bearing rocks and hydrochemical conditions of ore. It has been shown that with increased reservoir productivity, the need for frequent repair-and-renewal operations increases, which is explained by more active operating mode and, consequently, an increased load on operational elements. Characteristic patterns of changes in filtration coefficient and chemical composition of solutions in filter intervals have been revealed, allowing for more accurate prediction of the time and volume of the necessary repairs. Originality. Dependences of the quantity of repair-and-renewal operations of wells on reservoir productivity and geochemical conditions of ore at different stages of in-situ uranium leaching through boreholes have been obtained. Practical implications. The results obtained enable engineers and technologists to develop more reliable and flexible well maintenance and repair plans tailored to specific geologic-hydrodynamic and geochemical conditions. It reduces the risks of accidents, but also increases the overall uranium production level through more efficient use of equipment and working reagents.