Related by context. Frequent words. (Click for all words.) 57 coal mines 53 coalmines 52 mines 51 coal seams 51 collieries 50 coal miners 50 coal mining 49 coal mine 48 coalfields 48 bituminous coal 48 quarries 47 coalmine 46 miners 46 mined 46 coal 46 Sago mine 46 furnaces 45 stone quarry 45 colliery 45 coal seam 44 anthracite coal 44 dairy farms 44 mine shafts 44 underground 44 coke ovens 43 longwall mining 43 valley fills 43 blast furnaces 42 mine 42 anthracite 41 Marcellus Shale formation 41 quarry 41 limestone quarry 41 Pennsylvania 41 coalfield 41 drillers 41 silicosis 41 steel mills 41 artisanal miners 40 Appalachia 40 brick kilns 40 Coal Mine 40 MSHA 40 Sago Mine 40 West Virginia 39 longwall 39 compressor stations 39 fly ash 39 dairies 39 northeastern Pennsylvania 39 mining 39 adits 39 steelworkers 38 Mine 38 lodes 38 coke oven 38 bituminous 38 kilns 38 timbering 38 opencast 38 Sago mine disaster 38 fracking 38 mountaintop removal 38 wells 38 Hydraulic fracturing 38 Kemerovo region 38 potteries 38 underground workings 38 hog farms 37 CONSOL 37 mine shaft 37 geologic formations 37 lumber mills 37 coal miner 37 Mine Safety 37 mineshaft 37 sulfur dioxide emissions 37 dragline 37 methane 37 sulfur coal 37 geological formations 37 Marcellus shale 37 shale formations 37 Raspadskaya 37 wood boilers 37 UMWA 37 trapped miners 37 railroads 37 stopes 37 Quarries 37 Marcellus Shale 37 Mine Workers 36 Allegheny Mountains 36 mills 36 natural gas 36 tanneries 36 trapped underground 36 CNX Gas 36 caves 36 tunnels 36 uranium mines