TABLE 3

Results of water quality analysis of tap and surface water samples

ParameterDrinking water standardaValue in:
Tap waterSurface water (Han River)
Total colony count100 CFU/mlND4,700c
Total coliformsNDb/100 mlNDDetectedc
Escherichia coli/fecal coliformsND/100 mlNDDetectedc
Hardness300 mg/liter5161.0
pH5.8–8.57.37.4
Turbidity0.5 NTUd0.156.37c
Total solids500 mg/liter9487
Chloride (Cl)250 mg/liter117
Chlorine residual concn4.0 mg/literND0.48
Sulfate (SO4−)200 mg/liter911
Ammonium nitrogen (NH3-N)0.5 mg/literND0.09
Nitrate nitrogen (NO3-N)10 mg/liter2.32.0
Fluoride (F)1.5 mg/literNDND
Lead (Pb)0.01 mg/literNDND
Mercury (Hg)0.001 mg/literNDND
Cadmium (Cd)0.005 mg/literNDND
Trihalomethanes0.1 mg/liter0.029ND
Toluene0.7 mg/liter0.006ND
Ethylbenzene0.3 mg/liter0.007ND
Xylene0.5 mg/liter0.011ND
  • a Standards for drinking water quality from the Korean EPA.

  • b ND, not detected.

  • c The level of the contaminant exceeded drinking water quality standards.

  • d NTU, nephelometric turbidity units.