Constituent

Class 0

Class I

Class II

Class III

Electrical conductivity (mS/cm)

0 - 0.7

0.7 - 1.50

1.50 - 3.70

> 3.70

pH

6.0 - 9.0

5 - 6 or 9 - 9.5

4 - 5 or 9.5 - 10

< 4 or > 10

Nitrate (mg/L)

0 - 6

6 - 10

10 - 20

20

Sulphate (mg/L)

0 - 200

200 - 400

400 - 600

> 600

Chloride (mg/L)

0 - 100

100 - 200

200 - 600

> 600

Iron (mg/L)

0 - 0.1

0.1 - 0.2

0.2 - 2.0

> 2.0

Manganese (mg/L)

0 - 0.05

0.05 - 0.1

0.1 - 1.0

> 1.0

Cadmium (mg/L)

0 - 0.005

0.005 - 0.01

0.01 - 0.02

> 0.02

Zinc (mg/L)

0 - 3.0

3.0 - 5.0

5.0 - 10.0

> 10.0

Magnesium (mg/L)

0 - 30

30 - 70

70 - 100

> 100

Sodium (mg/L)

0 - 100

100 - 200

200 - 400

> 400