Related by context. Frequent words. (Click for all words.) 65 hydraulic fracturing 62 fracking 61 fracing 60 fracking fluid 58 fracking fluids 58 hydrofracking 58 Fracking 56 frac sand 56 flowback 55 tailing ponds 55 reinjection 55 shale 55 Hydraulic fracturing 54 contaminating groundwater 54 horizontal drilling 54 drillers 53 frack 53 extraction 53 carbon dioxide sequestration 53 dewatering 53 CO2 sequestration 52 injection wells 52 hydrocarbon 52 subsurface 52 wellbores 52 drilling 52 shale formations 51 tailings disposal 51 methane hydrates 51 shale gas 50 drilling fluids 50 wells 49 Marcellus Shale drilling 49 dissolved solids 49 Marcellus wells 49 geological formations 49 contaminate groundwater 49 fracking chemicals 49 coalbed methane 48 Marcellus Shale formation 48 polluted groundwater 48 Marcellus shale 48 chlorinated solvents 48 hydrocarbons 48 directional drilling 47 sumps 47 EOR 47 tar sands 47 Marcellus Shale 47 groundwater remediation 47 brine 47 shale deposits 47 groundwater 47 sorbents 47 dispersant chemicals 47 frac 47 chemicals 47 coal seams 47 hydrogeological 47 unconventional shale 47 kerogen 47 methane hydrate 47 zeolites 46 leaching 46 Fracturing 46 total dissolved solids 46 hydrofluoric acid 46 cased hole 46 Marcellus Shale wells 46 wireline logging 46 sediment sampling 46 bed methane 46 bioleaching 46 COGCC 46 biogenic 46 fly ash 46 Controlled burns 46 exploratory drilling 46 CBM wells 46 deepwater wells 46 degassing 46 fracs 46 harmful contaminants 46 dewater 46 bio remediation 46 pollute groundwater 45 geologic formations 45 desorption 45 glacial till 45 aquifer recharge 45 petroleum distillates 45 sandstone reservoirs 45 H2S 45 brines 45 natural gas 45 aquifers 45 slurry 45 gravity drainage 45 oil sands 45 solvents 45 coal seam