One of the ways to resolve the “green energy-economic development” dilemma, in which the coal industry is situated, is by the improvement of technologies and the integrated use of extracted resources, including methane gas as a clean energy source. Using the example of the Kirova mine, located in Kuznetsk coal basin—one of the ecologically unfavorable coal mining regions of Russia—this article discusses an integrated technology for the extraction of coalbed methane (ECBM), which makes it possible to reduce greenhouse gas (methane) emissions and improve the safety and intensity of coal mining. The Kirova mine, with its 3 Mt production in 2019, is one of the coal mining leaders in Russia. The available mining equipment has the potential to significantly increase the output; however, gas is a limiting factor to this. The customary approaches to coal seam degassing have already been petered out. The miners and mine science are facing a challenge to validate and test an alternative technology to ensure effective in-seam gas drainage prior to vigorous mining. This article gives an account of the improvement track record of the in-seam gas drainage technology used to pre-treat coal seams for intensive and safe extraction. This technology suggests, at the first stage, hydraulic loosening of the target coal seam through wells drilled from the surface (SSHL), then hydraulic fracturing (HF) of the coal seam through the boreholes drilled from underground development headings, followed by methane extraction from the high-permeability coal-gas reservoir created through standard in-seam gas drainage underground wells. Results are presented in this paper of field testing of the improved SSHL technique. Findings are presented on the effective parameters of the HF technology. Methodological recommendations are offered for selecting viable in-seam gas drainage technology.

The hypothesis of the piston effect during mine gas migration caused by fault reactivation was studied, with the use of computer modeling, to explain cases of a sudden appearance of mine gases on the earth surface in coal mining areas. The study is based on the factual data of the mode and amplitudes of subsidence along faults during mining, the morphology of the fault planes, and the theoretical ideas about the discrete nature of the fault wall displacement along uneven contact surfaces. It is taken into account that the walls of the fault, due to the asperity types “ridge” and “sag”, form contacts of the “ridge–ridge” and “ridge–sag” patterns. This study examines the situation where gas pressure in the fracture space can sharply increase due to the jerky displacement of reactivated tectonic fault walls with a rough fault plane. It is assumed that, in the first phase of reactivation, the fracture space expands as a result of the displacer opening and the fact that fault plane asperities engage in the “ridge–ridge” type of contact. With the subsequent relative displacement of the fault walls in the second phase of reactivation, the contact changes into the “ridge–sag” type and a sharp reduction in the fracture space volume occurs. It is shown that a “piston effect” emerges due to the reduction in fracture space and that it promotes an increase in gas pressure and stimulates gas movement to the surface through the available channels. The resulting “piston effects” may also be responsible for the suddenly raised gas content recorded in the air of surface structures and recurrent mine gas migration onto the surface. The findings expand our understanding of the sudden gasification of the earth surface and living spaces in coal mining areas and contribute to the understanding of the gas migration process, thereby helping to monitor hazards.

Sudden coal and gas outbursts pose a significant hazard in deep-seated coal seam extraction, necessitating reliable risk assessment methods. Traditionally, assessments focus on gas-dynamic parameters, but experience shows they must be supplemented with tectonic factors such as fault-related disturbances, weak interlayers, and increased fracturing. Even minor faults in the Karaganda Basin can weaken the coal massif and trigger outbursts. The integration of 3D modeling enhances risk evaluation by incorporating both dynamic (gas-related) and static (tectonic) parameters. Based on exploratory drilling and geophysical studies, these models map coal seam geometry, fault positioning, and high-risk structural zones. In weakened coal areas, stress distribution changes can lead to avalanche-like gas releases, even under normal gas-dynamic conditions. An expert scoring system was used to convert geological and gas-dynamic data into a comprehensive risk index guiding preventive measures. An analysis of Karaganda Basin incidents (1959–2021) shows all outbursts occurred in geological disturbance zones, with 43% linked to fault proximity, 30% to minor tectonic shifts, and 21% to sudden coal seam changes. Advancing 3D modeling, geomechanical analysis, and microseismic monitoring will improve predictive accuracy, ensuring safer coal mining operations.