Water Quality: RAPID CITY, SD

Known human carcinogen strongly associated with leukemia and other blood cell cancers.

Common source: Industrial discharges, gas station leaks, chemical plant emissions

EPA limit: 0.005 mg/L (5 ppb)

Probable human carcinogen associated with increased cancer risk; causes liver and kidney damage.

Common source: Industrial chemical production, fuel additive leaks, contaminated groundwater

EPA limit: 0.005 mg/L (5 ppb)

Cardiovascular damage and reproductive effects with long-term exposure; potential endocrine disruptor.

Common source: Runoff from corn and other crop herbicide applications

EPA limit: 0.003 mg/L (3 ppb)

Known human carcinogen strongly associated with leukemia and other blood cell cancers.

Common source: Industrial discharges, gas station leaks, chemical plant emissions

EPA limit: 0.005 mg/L (5 ppb)

Known human carcinogen strongly associated with leukemia and other blood cell cancers.

Common source: Industrial discharges, gas station leaks, chemical plant emissions

EPA limit: 0.005 mg/L (5 ppb)

Eye and nose irritation at high levels; long-term exposure above the MCL may cause liver and kidney damage.

Common source: Water treatment disinfectant added to kill harmful microorganisms

EPA limit: 4.0 mg/L (MRDL — Maximum Residual Disinfectant Level)

Known human carcinogen strongly associated with leukemia and other blood cell cancers.

Common source: Industrial discharges, gas station leaks, chemical plant emissions

EPA limit: 0.005 mg/L (5 ppb)

Known human carcinogen strongly associated with leukemia and other blood cell cancers.

Common source: Industrial discharges, gas station leaks, chemical plant emissions

EPA limit: 0.005 mg/L (5 ppb)

Causes methemoglobinemia (blue baby syndrome) in infants, reducing the blood's ability to carry oxygen.

Common source: Fertilizer runoff, septic systems, animal feedlots, natural deposits

EPA limit: 10 mg/L (as nitrogen)

Known human carcinogen linked to liver angiosarcoma; classified as a Group 1 carcinogen by IARC.

Common source: Leaching from PVC pipes; breakdown of industrial solvents in groundwater

EPA limit: 0.002 mg/L (2 ppb)

Known human carcinogen strongly associated with leukemia and other blood cell cancers.

Common source: Industrial discharges, gas station leaks, chemical plant emissions

EPA limit: 0.005 mg/L (5 ppb)

Known human carcinogen strongly associated with leukemia and other blood cell cancers.

Common source: Industrial discharges, gas station leaks, chemical plant emissions

EPA limit: 0.005 mg/L (5 ppb)