Related by context. Frequent words. (Click for all words.) 53 fracking fluids 53 contaminating groundwater 51 polluted groundwater 50 fracking fluid 50 Controlled burns 49 flowback 49 frac sand 47 coal slurry 47 contaminate groundwater 47 harmful contaminants 47 reinjection 46 hazardous waste 46 Hazardous waste 46 hydraulic fracturing 46 chlorinated solvents 46 methane 46 fly ash 46 toxic pollutants 46 total dissolved solids 46 hazardous chemicals 46 methane gas 46 chemicals 45 toxic wastes 45 pollutants emitted 45 wastewater 45 toxic chemicals 45 dissolved solids 45 naturally occurring methane 45 radionuclides 45 fracking 45 naturally occurring radioactive 45 toxic substances 45 livestock manure 45 toxic gases 45 contaminated soils 44 contaminated soil 44 toxic waste 44 mine tailings 44 contaminants 44 radioactive substances 44 smokestack emissions 44 evaporation ponds 44 hazardous fumes 44 suspected carcinogen 44 drillers 44 biosolids 44 flammable gases 44 groundwater 43 fumigants 43 Fracking 43 silica dust 43 dredge spoils 43 incineration 43 nonhazardous 43 Marcellus wells 43 methylene chloride 43 tailing ponds 43 hydrogen sulfide 43 dredged material 43 chlorides 43 sludge 43 Hazardous materials 43 hazardous wastes 43 wastewater discharges 43 hog manure 43 Rotenone 42 chlorine dioxide 42 hazardous substances 42 Hydrogen sulfide 42 VX nerve gas 42 pollutants 42 effluents 42 transuranic waste 42 mill tailings 42 carcinogenic chemicals 42 hazardous materials 42 herbicides pesticides 42 quicklime 42 gases emitted 42 americium 42 cleaning solvents 42 noxious chemicals 42 OEPA 42 radioactive materials 42 bio solids 42 leachate 42 hazmat crews 42 ash ponds 42 Hydraulic fracturing 42 flammable chemicals 41 Radiation Control 41 superheated steam 41 munitions 41 Dunkard Creek 41 disinfection byproducts 41 DEP 41 gases 41 pollute groundwater 41 radioiodine 41 contaminated 41 slurry