The name of the famous geologist and teacher Alexander Vladimirovich Lvov (1871-1941) is well known not only to specialists, but also to all those interested in the history of scientific research in Siberia. Lvov stood at the origins of geological education in Irkutsk, created a scientific school of engineering geology and permafrost science in Siberia, participated in the study of minerals of the Baikal region and mining conditions of the construction and operation of the Trans-Siberian Railway. One of his research areas was participation in surveying sites for the construction of hydroelectric power plants in Priangarie.

In 2012-2024, monitoring series of activity ratios were obtained²³⁴U/²³⁸U, U concentrations and Si - Na/Li temperatures in the groundwater reservoir of the Arshan resort area in the Tunka Valley. Taking into account the published materials and existing ideas about the genesis of groundwater in the Tunka Valley, it is assumed that the uranium components in them are determined by uranium dissolution under the influence of oxidizing and reducing gases. It is assumed that isotopic equilibrium ²³⁴U – ²³⁸U in cold carbonaceous mineral waters may serve as an indicator of the impact of oxidized fluids on their deep reservoir, and disturbance of equilibrium - as an indicator of the change of the impact of oxidized fluids by reduced ones. Monitoring data series are used to track the paragenetic relations of hydrogeochemical, seismic and volcanic processes in the Baikal rift system.

Based on the results of the 2013-2022 monitoring, time-varying ratios of mineral water components from carbonates containing gypsum and anhydrite are determined when the activity ratios change²³⁴U/²³⁸U (ОА4/8) 11.82 to 15.71. With the increase of this indicator in mineral water the activity also increases ²³⁴U (А4) with manifestation of maxima and minima in 2017-2022. Variations of A4 are consistent with changes in the total mineralization, the contents of all macrocomponents (Ca, Na, Mg, Si, K, S and Cl) and part of microcomponents (U, Li, B, V, Mn, Br, Y, Rb and Sr) with an inverse relationship with the concentrations of another part of microcomponents (Cu, Sc, Nb, Mo, Mo, Ba, Ti, Zr and Cr). It is concluded that U isotopes vary in mineral water due to changes in the chemical dissolution of carbonates. Mineral water is enriched in recoil atoms ²³⁴U similar to other solubilizing components, whereas OA4/8 is complicated by the dependence of U solubilization on redox potential (ORP).