Related by context. Frequent words. (Click for all words.) 47 Sulfur dioxide 46 sulfur dioxide nitrogen oxide 46 methane 44 poisonous carbon monoxide 44 pollution 44 airborne particulates 44 sulfur dioxide nitrogen oxides 43 groundwater withdrawals 43 smokestack emissions 43 greenhouse gases GHGs 43 highly combustible methane 43 Nitrogen oxides 42 MSHA 42 noxious gases 42 ammonia nitrogen 42 combustion gases 42 sediment runoff 42 combustible gases 42 Utah Crandall Canyon 42 pollutant discharge 42 deplete oxygen 42 potent greenhouse gas 42 No.2 reactor 41 contaminating groundwater 41 cave ins 41 silica dust 41 flammable vapors 41 carbon dioxide 41 SO2 emissions 41 pollutant emissions 41 mercury emissions 40 particulate matter emissions 40 heat trapping carbon dioxide 40 sulfur dioxide emissions 40 global warming gases 40 greenhouse gases 40 air pollution 40 emissions 40 heat trapping gases emitted 40 Yuzhkuzbassugol 40 harmful pollutants 40 toxic pollutants 40 mercury pollution 40 Lethal gases 40 emission 40 methane gas 40 sulfur dioxide SO2 40 pollutants emitted 40 Coal Mine Safety 40 absorbs carbon dioxide 40 carbon dioxide emissions 40 unvented 40 ash ponds 40 greenhouse gases endanger 39 gases 39 sulfur dioxide 39 sequester carbon dioxide 39 pollutants 39 emmissions 39 coal mine 39 subsurface 39 heat trapping greenhouse gas 39 Darby Mine 39 GHGs 39 Rostekhnadzor 39 MINER Act 39 Dunkard Creek 39 air toxics 39 evaporative emissions 39 acid rain 39 carbon dioxide emission 38 CO -2 38 curb overcapacity 38 carbon dioxide methane nitrous 38 odorless colorless gas 38 Rubbertown 38 enact stricter 38 productivities 38 coal mines 38 heat trapping gases 38 harmful ultraviolet radiation 38 gases emitted 38 SoCal wildfire 38 install scrubbers 38 poisonous gases 38 pollutant 38 Nortel remedial 38 particulate matter PM 38 Hobet 38 manure pits 38 flammable gases 38 Kemerovo region 38 Elandsrand 38 carbon dioxide CO2 38 sulfur hexafluoride 38 W.Va. gov 38 chimney stacks 38 heat trapping greenhouse gases 38 combustible dust 38 spokeswoman Amy Louviere 38 cement kiln