When it comes to coal, the United States is what the Middle East is for oil. That fact is not lost on an industry competing for relevancy at a time when it’s undersold by natural gas and renewable energy. It’s not lost on the coal-producing towns in the nation that have long relied on the mineral for jobs and economic development. And it’s certainly not lost on Greg Merle, whose company is pitching what he hopes — what he believes — might just be the answer for a declining industry desperate to remain viable. Merle is the president of Riverview...