Of course not all coal miners will want to be coders, but why can't you teach a coal miner to code? And why do people assume that coal miners are not interested in coding. And why do people assume they don't have the intellectual ability to handle it.
Maybe I'm being arrogant, but I'm guessing coal miners chose that life because they weren't suited for much else. I'd wager that most of these guys are below average intelligence, where as most programmers are above average intelligence.
Of course, (from a quick google search) the pay looks surprisingly decent, so maybe I'm wrong. The pay is probably accounting for a dangerous, unhealthy, and miserable line of work. Still, I have to believe that if you can do something else, you'd already be doing it.