Back a few years, the major oil company I worked for bought up several coal mines. The argument was that coal was more readily available and cheaper than imported petroleum, so why not add coal to the company's energy portfolio. A laboratory was set was set up and staffed with excellent researchers, and all sorts of experiments and a pilot plant set up aimed at clean production of energy from coal. It could be done in the laboratory, but the methods were too expensive for commercial practice. The company has since sold the coal properties. Advances are being made, but research seems not to have produced an economic clean-up method.
The environmental damage of coal-mining is always there. Reclamation only goes so far, and the more easily reclaimed lands are flatlands where agriculture is disrupted (e. g., Illinois, etc., where much coal is mined in open pits). The destruction of mountainous areas to get anthracitic coal is a crime. Lower coal grades, with some modification of plants, can and is used successfully.