Remote seismic monitoring of the of the first stage of the Vilyui HPP cascade using records from the “Chernyshevsky” seismic station

Advancements in digital seismic signal processing have significantly enhanced the ability to analyze low-amplitude signals from both natural and anthropogenic sources. This article investigates the potential for remotely detecting seismic signals generated by operating equipment at the first and second stages of the Vilyui Hydroelectric Power Plant cascades (HPP-1 and HPP-2) within the engineering and geological conditions of the permafrost region. The study employs methods and software developed by the Federal Research Center “Geophysical Survey of the Russian Academy of Sciences”. Seismic data from the Yakut Regional Seismological Centre network, including records from the “Chernyshevsky” seismic station and the Vilyui HPP-1 and HPP-2 located 1.256 kilometers and 1.456 kilometers away, respectively—were processed. Averaged spectral graphs of seismic signals over various time intervals were constructed, revealing numerous monochromatic signals. Analysis of these graphs, combined with technical documentation for the Vilyui HPP-1 and HPP-2 equipment, enabled the establishment of correlations between the processed signal and the operational characteristics of the equipment. An analysis of an emergency event on March 4, 2023, caused by incorrect operation of the control systems for the generating equipment at the Vilyui HPP-1 and HPP-2, confirmed that the identified signals are related to the generating equipment. The deviations of the operating equipment frequencies from their nominal values, along with the timing of technical malfunctions, were identified. In conclusion, the methodology was assessed and confirmed to be appropriate for conducting seismic and geotechnical monitoring of engineering structures located in permafrost environments.