The phrase "mining coal" means the process of digging and extracting coal, which is a type of black rock that can be used as a fuel to generate energy. Full definition
Since then, cheap natural gas and shallow, easy - to - mine coal burned in traditional power plants have prevented the technique from taking off. (sciencemag.org)
We have to find more environmentally sound ways of mining coal than simply blowing the tops off mountains. (climatesciencewatch.org)
«And we all know what the greatest contribution to climate change is: that's mining coal for export.» (scientificamerican.com)