Ключевые слова: black, black coal, coal, coal mining, conveyor, deep, deposit, dirt, drilling, energy, energy source, equipment, excavation, excavation site, extraction, fossil, heavy, industry, labor, laborers, machine, machinery, mine, mine tunnel, mine workers, minerals, mining, mining equipment, mining shaft, mining site, natural resources, natural stone, power, production, resources, rock, site, tools, tunnel, tunnel workers, underground,