Related by context. Frequent words. (Click for all words.) 65 ppb 57 perchlorate 57 arsenic 57 picocuries per 57 hexavalent chromium 54 nanograms per 53 fecal coliform bacteria 53 Safe Drinking Water 53 trichlorethylene 53 contaminant 53 radium 52 fecal coliform 51 coliform bacteria 50 radioactive iodine 50 radioactive cesium 50 micrograms 50 chromium 50 TCE 49 USEPA 49 ppm 49 coliform 49 benzene 49 tritium 48 becquerels 48 contaminants 48 microgram 47 TMDL 47 maximum allowable 47 PFOS 47 turbidity 47 nitrate 46 Clean Water Act 46 nanograms 46 carcinogen 46 fecal bacteria 46 Arsenic 45 Drinking Water 45 fluoride 45 nitrates 45 ATSDR 45 cesium 45 per milliliter 44 Concentrations 44 PCBs 44 dioxin 44 per deciliter 44 chlorination 44 groundwater 44 trace amounts 44 milligrams 44 ozone 44 strontium 44 concentrations 44 Perchlorate 43 chloride 43 selenium 43 dioxins 43 ng ml 43 E. coli bacteria 43 mercury contamination 43 pesticide residue 43 suspended solids 43 phosphorus 43 barium 43 Adequate Yearly Progress AYP 43 dissolved oxygen 42 allowable 42 radionuclides 42 contaminated groundwater 42 methylmercury 42 iodine 42 groundwater contamination 42 hydrogen sulfide 42 radon 42 Disease Registry 42 fine particulate matter 42 Environmental Protection Agency 42 E. coli 42 vinyl chloride 42 thallium 42 PAHs 42 Toxic Substances Control 42 pollutant 42 cadmium 41 ng mL 41 DEQ 41 radioactivity 41 Iodine 41 phosphorous 41 Toxic Substances 41 EPA 41 contaminated 41 Cryptosporidium 41 mg dl 41 PFOA 41 wastewater discharge 41 milliliters 41 manganese 40 mercury 40 PM# [003] 40 human carcinogen