TOLERANCE LIMITS FOR TRADE EFFLUENTS

 

 

Tolerance Limits for Discharge of Trade Effluents into

Sl.
No.
Characteristics
Inland surface Waters
(a)
Public Sewers
(b)
On Land for Irrigation
(c)
Marine Coastal Areas
(d)

1

Colour & Odour

-

-

-

-

2

Suspended Solids mg/l

100

600

200

a. For process waste water-100
b. For cooling water effluent 10 percent above total suspended matter of influent cooling water

3

Particle Size of Suspended Solids

Shall pass 850 micron I.S.Sieve

-

-

a. Floatable solids maximum 3mm.
b. Settlable solids maximum 850 microns

4

Dissolved Solids (inorganic) mg/l

2100

2100

2100

-

5

pH Value

5.5 to 9

5.5 to 9

5.5 to 9

5.5 to 9

6

Temperature

45°C at the point of discharge

45°C at the point of discharge

 

45°C at the point of discharge

7

Oil & Grease mg/l

10

20

10

20

8

Total Residual Chlorine mg/l

1.0

-

-

1.0

9

Ammonical Nitrogen (as N) mg/l

50

50

-

50

10

Total Kjeldahl Nitrogen (as N) mg/l

100

-

-

100

11

Free Ammonia (as NH3) mg/l

5.0

-

-

5.0

12

Bio Chemical Oxygen Demand (3 days at 27°C) mg/l

30

350

100

100

13

Chemical Oxygen Demand mg/l

250

-

-

250

14

Arsenic (as As ) mg/l

0.2

0.2

0.2

0.2

15

Mercury (as Hg) mg/l

0.01

0.01

0.01

0.01

16

Lead (as Pb ) mg/l

0.1

1.0

1.0

1.0

17

Cadmium (as Cd ) mg/l

2.0

1.0

1.0

2.0

18

Hexavalent Chromium (as Cr +6 ) mg/l

0.1

2.0

0.1

0.1

19

Total Chromium (as Cr) mg/l

2.0

2.0

2.0

1.0

20

Copper (as Cu) mg/l

3.0

3.0

3.0

3.0

21

Zinc (as Zn) mg/l

1.0

1.5

1.5

1.5

22

Selenium (as Se) mg/l

0.05

0.05

0.05

0.05

23

Nickel (as Ni) mg/l

3.0

3.0

3.0

3.0

24

Boron (as B) mg/l

2.0

2.0

2.0

2.0

25

Percent Sodium %

-

60

60

-

26

Residual Sodium Carbonate mg/l

-

-

5.0

-

27

Cyanide (as CN) mg/l

0.2

2.0

0.2

0.2

28

Chloride (as Cl ) mg/l

1000

1000

600

-

29

Fluoride (as F) mg/l

2.0

1.5

2.0

1.5

30

Dissolved Phosphates (as P) mg/l

5.0

-

-

-

31

Sulphates (as SO4) mg/l

1000

1000

1000

1000

32

Sulphides (as S) mg/l

2.0

-

2.0

5.0

33

Pesticides

Absent

Absent

Absent

Absent

34

Phenolic Compounds (as C6H5OH) mg/l

1.0

5.0

5.0

5.0

35

Radio Active Materials

a. Alpha emitters micro curie/ml

10-7

10-7

10-8

10-7

b. Beta emitters micro curie/ml

10-6

10-6

10-6

10-7

TOLERANCE LIMITS FOR SEWAGE

Sl . No.

Characteristic

Tolerance Limit

1

pH

5.5 to 9

2

Total Suspended Solids mg/l

30

3

Biochemical Oxygen Demand
(3 days at 27°C.) mg/l

20