This study is on the health risks of surface coal mining (also known as mountaintop removal) on the surrounding communities, not on the miners. As the article notes there is some evidence of unusually high lung cancer and birth defect rates in communities near such mines.
I was eating dinner with two doctors about a month ago, and they were discussing this. They said it was difficult to prove that coal mining causes things like lung cancer in the miners themselves because it is just about impossible to find a coal miner who doesn't smoke.
Would they get cancer sooner or have different effects than non-miner smokers?
I think the sample sizes might get out of hand as you'd need a good deal of miner and control subjects to filter out the noise.
So what you're saying is coal mining causes smoking.
Correlation <> causation.
Kind of like the joke about trying to find a carpenter that isn't a drunk.
What does that have to do with mountain top removal causing health problems in the surrounding communities? Because the study that this article refers to isn't about lung cancer in coal miners.
It would be interesting to know the coal miner cancer rate compared to smokers in the general population.
if you read the article they're talking about the impact of it on communities nearby
"widely known" is useless in science. Anyone can claim that they know something is X, i.e. pretty much every one of Trump's statements is him claiming that "I know <insert subject> is bad, therefore we must do <insert solution>". His statement isn't any more true than merely stating that he's wrong without anything to prove his falseness. Science and actual studies do make it true that he's wrong.