One of the main ways to prevent in longwall faces of single gently sloping seams of sudden coal and gas emissions is to weaken the coal mass with large-diameter advanced boreholes. These emissions in recent years in the mines of Donbass exceed 25% of all emissions. Despite the relevance of the method until recently there is no universally recognized methodology for determining the density of the protective network of wells. The radius of influence of wells is calculated according to the formulas of V. V. Khodot, A. V. Pavlov or according to the method of MacNII ...

The Yar-Bishkadak field, which supplies brine to a number of chemical enterprises in Bashkiria, develops a section of salt deposit with a thickness of 200-700 m, with the thickness of overlying rocks being 400-500 meters. Development is carried out by isolated chambers, which are created by salt leaching through wells drilled from the surface. The adopted technology - step leaching - provides creation of chambers of approximately cylindrical shape with a diameter of 80-100 m and height by the end of mining equal to the thickness of the salt deposit (the height of individual chambers currently reaches 100-150 m) ....