4. Environmental Legislation
01
Environmental Legislation
means a plan of action
adopted by the
Government rationalizing
the course of action.
The Environmental
Legislation although
varies from country or
continent focuses on a
common goal of secure
and sustainable living at
earth.
The Environmental
Legislation tries to
enact all the laws of
environment in a
justifiable manner.
02 03
5.
6. 1.
In Indian Constitution, two articles related to Environmental
Protection are:
2.
1. Article 48 A (Directive Principle of State Policy)
“The state shall endeavor to protect and improve the environment and to
safeguard the forests & wildlife of the country”.
2. Article 51 A (g) (Fundamental duties of citizens)
“It shall be the duty of citizen of India to protect & improve the natural
environment including forests, lakes, rivers and wildlife & to have
compassion for living creatures”.
7. The Importance of Water:
•Clean water is essential for the human
body
• The human body is made up of
different systems which mainly contains
water.
•Contaminants present in water can bio-
accumulate in the body causing health
issues – i.e. carcinogens can bio-
accumulate possibly causing cancer in
the future.
Brain 75 % Water
Lungs 86% Water
Muscles 75% Water
Circulatory System
80% Water
8. • Water is an extremely stable compound
and is composed of Hydrogen & Oxygen atoms.
•It is referred to as the universal solvent as it dissolves
more substances than any other liquid.
•Water is unique as it is only natural substance that is
found in three states – liquid, solid, gas
•Water is very rarely in pure "distilled‟ form.
•Water will always contain salts, nutrients & particulates
depending on local conditions.
Water Molecule:
2 Hydrogen atoms
1 Oxygen atom
9. pH:refers to water being acidic, basic or
neutral; pH is affected by chemicals
therefore is a good indication that water may
be changing chemically
•pH stands for the potential of hydrogen
•The neutral point of 7 indicates the
presence of equal concentrations of free
hydrogen & hydroxide ions
•Each decrease in pH by one pH unit means
a tenfold increase in concentration of
hydrogen ions – therefore more acidic
Measurable Properties of Water: pH
10. •Turbidity can make water
either cloudy or opaque
depending on what makes
up turbidity
•Turbidity is measured in
NTU‟s (Nephelometric
turbidity units)
• The higher the NTU value,
the higher
the intensity of scattered light
•Turbidity is
measured with a
turbidimeter
•Turbidimeter is
calibrated using
vials of solution
which contain
different NTU levels
Measurable Properties of Water: Turbidity
11. what substances or organisms are we
interested in testing for-- and why?
what procedures and equipment do we
use to make the measurements, and
how do they work?
TWOASPECTS OF WATER ANALYSIS
12. A. Physical
Aspects
1. Taste
2. Odor
3. Color
4. Turbidity
5. pH
6. Total Dissolved Solids
B. Chemical Aspects
1. Arsenic
2. Cadmium
3. Lead
4. Benzene
5. Iron
6. Manganese
7. Chloride
8. Sulfate
• ** Chlorine Residual
13. ⦁ This part deals
primarily with the
measurement of
the physical
properties of the
sample
⦁ Provides first warning
of potential hazards
in the environment
14. ⦁ Refers to the gustatory sensations
◦ Bitter – caffeine ( Strong coffee)
◦ Salty – sodium chloride (Chlorinated water)
◦ Sour – citric acid (lemon juice)
◦ Sweet – sugar (syrup)
⦁ Flavor – gustatory, olfactory and trigeminal
sensations
⦁ Methods:
◦ Sensory Evaluation Technique
⦁ Only used on samples known to be safe for
ingestion
⦁ Standard: No Objectionable Taste
15. ⦁ Affected by organic and inorganic chemicals
present in water
⦁ Provide qualitative descriptions of odor
intensity
⦁ Method:
◦ Sensory Evaluation Technique
⦁ Standard: No Objectionable Odor
16.
17. ⦁ Color of surface and groundwater results
primarily from the presence of natural
organic matter, particularly aquatic humic
matter
◦ Humic matter consists of humic and fulvic acids –
yellow-brown color
⦁ Substances that adds color to water:
◦ Suspended particles
🞄 Clays, algae, iron, manganese oxides
⦁ Color usually removed from potable water for
aesthetic purposes
18. ⦁ True Color
◦ Color of water from which the turbidity has been
removed
◦ Standard: ≦ 5 Color Units
⦁ Apparent Color
◦ Color due to substances in the solution and
suspended matter
◦ Contributed principally by colloidal or suspended
material
◦ Standard: ≦ 10 Color Units
⦁ Methods: Visual Comparison Colorimetric
19. ⦁ Caused by suspended and
colloidal material
◦ Clay, silt, finely divided organic and
inorganic
matter, plankton and other microbes
⦁ Method: Turbidimetry
⦁ Standard: 5 NTU
20. ⦁ Acidity
◦ Attributed to the presence of strong mineral acids and
weak acids and hydrolizing salts such as iron and
aluminum sulfate
◦ Contribute to corrosiveness and influence chemical
rates, chemical speciation and biological processes
⦁ Alkalinity
◦ Refers to the acid-neutralizing capacity of water
◦ Attributed to the carbonate, bicarbonate and hydroxide
content and borates, phosphates and silicates or other
bases
⦁ Method: Electrometric method (pH meter)
⦁ Standard: 6.5 to 8.5
21. ⦁ Waters with high dissolved solids generally
are of inferior palatability
⦁ Portions of solids that passes through a filter
of nominal pore size
⦁ Methods: Gravimetric, dried at 180°C
⦁ Standard: ≦ 500
22. ⦁ Various forms of chemicals are present in
drinking water that may lead to some health
problems
⦁ Inorganic constituents
◦ Arsenic, lead, chromium and cadmium
🞄 Suspected carcinogens
⦁ Organic constituents
◦ Due to decomposition of organic debris, domestic,
agricultural, industrial, water treatment
23. ⦁ Presence of arsenic in water is due to mineral
dissolution, industrial discharges, application of
pesticides
⦁ Health Effects: severe poisoning and carcinogenic
⦁ Methods: Inductively Couple Plasma/Mass
Spectrophotometry; hydride generation Atomic
Absorption Spectrophotometry; Silver
Diethyldithiocarbamate Method, Electrothermal
Atomic Absorption Spectrophotometry (Graphite
furnace AAS)
⦁ Standard: ≦ 0.05 mg/L
24. ⦁ extremely toxic and accumulate in the
kidneys and liver
◦ Causes dysfunction of the kidneys
⦁ Methods: Inductively Couple Plasma/Mass
Spectrophotometry (ICP/MS), Flame Atomic
Absorption Spectrophotometry (FAAS)
⦁ Standard: ≦ 0.003 mg/L
25. ⦁ Presence in water supply comes from industrial,
mine and smelts discharges or from the
dissolution of plumbing and plumbing fixtures
⦁ Toxic and cummulative poison
⦁ Method: Inductively Couple Plasma/Mass
Spectrophotometry (ICP/MS), Flame Atomic
Absorption Spectrophotometry (FAAS),
Electrothermal Atomic Absorption
Spectrophotometry (EAAS), Anodic Stripping
Voltammetry; Dithizone
⦁ Standard: ≦ 0.01 mg/L
26. ⦁ Results with high contamination from human
or animal waste
⦁ Methods: Cd Reduction Method, Capillary Ion
Electrophoresis Colorimetric (Diazotization);
Flow Injection Analysis
⦁ Standard: ≦ 0.01 mg/L
27. ⦁ Presence is due to industrial effluents,
atmospheric pollution due to vehicular
emissions
⦁ Method: Gas Chromatography/Mass
Spectrophotometry
⦁ Standard: ≦ 0.01 mg/L
28. ⦁ Elevated iron levels can cause stains in
plumbing, laundry, and cooking utensils
⦁ Imparts objectionable taste and color
⦁ Ferrous state -> oxidized -> ferric state
(reddish precipitate)
⦁ Method: Phenanthroline, Atomic Absorption
Spectrophotometry, Colorimetric Method
⦁ Standard: ≦ 0.01 mg/L
29. ⦁ Elevated manganese can cause stains in
plumbing, laundry, cooking utensils
⦁ Mn2+ -> oxidized -> MnO2 black precipitate
⦁ Methods: Perfurate Method, Atomic
Absorption Spectrophotometry, Inductively
Color Plasma/Mass Spectrophotometry
⦁ Standard: ≦ 0.04 mg/L
30. ⦁ Major inorganic anions in water
⦁ Produces salty taste if the cation is sodium
⦁ High chloride content may harm metallic
pipes and structures
⦁ Method: Argentometric Method, IC
⦁ Standard: ≦ 250 mg/L
31. ⦁ Occurs naturally in water
⦁ Method: Turbidimetric Method, Ion
Chromatography, Gravimetric Method
⦁ Standard: ≦ 250 mg/L
32. Generally soaps create foam in water, but in present of some materials the
foam creation is reduced and need more soap for producing foam, and this
condition of water is called water hardness.
The presence of Calcium, Magnesium salt i.e. bicarbonates, sulphates,
chloride in water is called causes of hardness of water. The water which contains
these salts is called hard water. Hard water does not easily form lather with soap
as the salt of Calcium and Magnesium react with soap to form insoluble organic
salts.
CaSO4 + 2RCOONa → (RCOO)2Ca ↓ + Na2SO4
MgSO4 + 2RCOONa → (RCOO)2Mg ↓ + Na2SO4
WATER HARDNESS
34. 1. Temporary Hardness: Temporary hardness is due to the presence of bi-carbonates of
calcium and magnesium. This type of hardness is called temporary hardness. Because it can
be removed by easy means like boiling. When temporary hard water is boiled, the
carbonates decompose with liberation of carbon-dioxide and precipitation of the insoluble
Carbonates which are reformed.
Ca(HCO3)2 CaCO3 ↓ + CO2 + H2O
Mg(HCO3)2 MgCO3 ↓ + CO2 + H2O
MgCO3 is slightly soluble in water but heating will cause its hydrolysis into
the much less soluble Mg(OH)2.
MgCO3 + H2O → Mg(OH)2 + CO2
So simple boiling and filtering of water remove temporary hardness.
TEMPORARY HARDNESS
35. 2. Permanent Hardness:
It is due to the presence of chlorides of Sulphates of Calcium and Magnesium. This
type of hardness is called permanent hardness. These salts do not decompose on
boiling. So permanent hardness can’t be removed easily. It can be removed by lime
when MgSO4 is responsible for hardness.
CaSO4 + Na2CO3 → Na2SO4 + CaCO3
MgSO4 + Na2CO3 → Na2SO4 + MgCO3
MgSO4 + Ca(OH)2 (Lime) → Mg(OH)2 + CaSO4
N.B. PH of drinking water is around 7 (Neutral)
PERMANENT HARDNESS
36. UNITS OF HARDNESS
Hardness is expressed by-
1. PPM (Parts Per Million)
2. In degrees (Grains/ gallon)
1. PPM: The number of grains of calcium carbonates which is present in one million
grains of water is called PPM.
1 grains of Calcium Carbonate present in 1 million grains water
2.In degrees: The number of grains of Calcium carbonates which is present in 70,000
grains of water.
Another unit of water hardness-
3.GPG – Grains Per U.S. Gallon
4. PP/ 100000
5. GPG imperial – Grains Per British Gallon
Here,
1 U.S. gallon = 8.33 pounds
1 British gallon = 10 pounds (Used in our country)
1 grain = 1/7000
pound;
i.e. 7000 grains = 1 lb
37. STANDARD/ QUALITY OF DYE HOUSE WATER
STANDARD FOR TEXTILE DYE HOUSE WATER SUPPLY/ SPECIFICATION FOR PROCESS WATER/
IDEAL QUALITY IF FEED WATER FOR TEXTILE INDUSTRY
MINIMUM STANDARD PERMISSIBLE CONCENTRATION
Color Colorless
Smell Odorless
PH value Nature (PH 7.8)
Water hardness Less than 50 dH
Dissolved solids Less than 1 ml/L
Solids deposits Less than 50 mg/ L
Organic substances Less than 20 mg/ L
Inorganic salt Less than 500 mg/ L
Iron (Fe) Less than 0.1 mg/ L
Copper (Cu) Less than 0.005 mg/ L
Nitrate (NO3) Less than 50 mg/ L
Nitrite (NO2) Less than 5 mg/ L
Iron and copper are responsible for the creation of spots on fabric. For those spots we
can use ‘spot removers’.
38. ESTIMATION OF WATER HARDNESS
Water hardness can be determined by the following 2 methods-
1. By titration with standard soap solution:
In this method total hardness/ permanent hardness can be measured.
2. By titration with HCl:
In this method temporary hardness can be measured.
ESTIMATION OF WATER HARDNESS
39. ESTIMATION OF TEMPORARY HARDNESS BY TITRATION BY TITRATION WITH HCL:
For determining temporary hardness 200cc hard water
is taken into a 500 cc bottle. Then few drops of methyl
orange is added in it as an indicator. Now titration is carried
out by adding 0.1N cold HCl until the yellow color of
methyl orange turns colorless.
Here, each meal 0.1N HCl is equivalent to 0.005 gm of
CaCO3. The associated reactions are as follows:
Ca(HCO3)2+ 2HCl → CaCl2 + CO2 + H2O
Mg(HCO3)2 + 2HCl → MgCl2 + CO2 + H2O
EXPRESSION:
Multiplying the required amount of 0.1N HCl for
titration in
cc by –
2.5 gives French hardness
1.78 gives English hardness
1.4 gives German hardness.
Permanent hardness can be found by deducting the
temporary hardness from total hardness i.e.
Permanent hardness = Total hardness – Temporary hardness
40. 1. Lime-soda process
2. Base exchange process
3. Demineralization process
4. Sequestering agent
Methods for water softening
41. In this process hydrated lime and sodium carbonate is used to remove the
hardness.
For temporary hardness –
Ca(HCO3)2 + Ca(OH)2 2 CaCO3 + 2 H2O
Mg(HCO3)2 + Ca(OH)2 MgCO3 + CaCO3 + 2 H2O
MgCO3 + Ca(OH)2 Mg(OH)2 + CaCO3
For permanent hardness –
CaSO4 + Na2CO3 CaCO3 + Na2SO4
MgCl2 + Ca(OH)2 CaCl2 + Mg(OH)2
CaCl2 form is removed by –
CaCl2 + Na2CO3 2 NaCl + CaCO3
1. Lime-Soda process
42. PROCESS
The lime soda [Na2CO3 + Ca(OH)2] and coagulant (NaAlO2) are metered into
the reaction tanks together with a predetermined amount of hard water.
Agitation is brought about in every tank by a large propeller. When sufficient
time has elapsed for the precipitation to be completed
the water passes through filters to the soft water storage.
THE RESULT
By this process we can produce soft water with 50-100 ppm. But if temperature
and agitation are increased water with 5-20 ppm hardness can be obtained.
Lime-Soda process
43. In lime soda softening plant main parts are-
1. Reagent tank (Soda lime + Coagulants)
2. Reaction tank
3. Filter
4. Soft water storage tank.
44. comes in contact with Zeolites, the water softened and soft water is collected
from the downward outlet. When sufficient amount of hard water has passed
then the supply of hard water is closed and then flow is reserved and beds of
Zeolites and other substances are cleaned. Then the cleansed is regenerated by
passing 10% NaCl through the Zeolites and the Zeolites are regenerated again.
2. Zeolite Process
The Zeolites are taken in the vessel as shown in figure with other required
substances. When the hare ward is passed through the inlet,
45. Regeneration of Zeolites
For regeneration of sodium salt of the zeolite involves passing a concentrated
solution (generally 10%) of NaCl through the exhausted zeolites.
Ca-Permutit + 2NaCl 2Na-Permutit + CaCl2
ADVANTAGES:
1. By this process water can be softened up to 0-2 ppm, even zero
hardness can be obtained.
2. Less floor space is required for machines.
3. Here only one chemical is used and no objectionable chemical is
produced as by product.
4. Here regeneration is possible and it is easy to carry out with CaCl
solution.
46. Permutit process (Ion exchange method)
Permutit’ means exchange; in this process, hard water is treated with base
exchange complex or Zeolites to remove the hardness of water. Zeolites are
naturally occurring insoluble mineral of the sodium aluminosilicate type
complex (e.g. NaAlSiO4. 3H2O ≈ Na-Permutit). This type of ion exchanger
may produce artificially.
Basic Principle
For temporary hardness –
2Na-Permutit + Ca(HCO3)2 Ca-Permutit↓ + 2NaHCO3
For permanent hardness –
2Na-Permutit + CaSO4 Ca-Permutit↓ + Na2SO4
2Na-Permutit + MgSO4 Mg-Permutit↓ + Na2SO4
2Na-Permutit + MgCl2 Mg-Permutit↓ + 2NaCl
47. A) Cation exchange:
Cation exchanger has replaceable H+ or Na+ ion. Cation exchange resins are
organic in nature (made up by polymerization of polyhydric phenols with
formaldehyde. It is also manufactured by sulphonation of coal). These reagents
replace the ions of hard water by hydrogen, leaving the water an equivalent
amount of acids.
For temporary hardness –
H2R + Ca(HCO3)2 CaR + 2H2CO3
H2CO3 CO2 + H2O
For temporary hardness –
H2R + CaCl2 CaR + 2HCl
H2R + CaSO4 CaR + H2SO4
General reaction –
2(Polymer – SO3¯H+) (s) + Ca²+ (aq) ↔ (Polymer – SO3¯)2Ca²+ (s) + 2H+ (aq)
48. B) Anion exchange:
Anion exchanger has replaceable OH¯ ion. In this unit acid is absorbed by the
anionic exchanger which displaces the anionic groups like Cl¯, SO4¯ ¯, from
acids.
General reaction –
2(Polymer – NR3+OH¯) (s) + 2Cl¯ (aq) ↔ 2(Polymer – NR3+Cl¯) (s) + 2HO¯
(aq)
• Water can be totally demineralised by firstly exchanging all cations using s
strongly acid form of a cation exchanger. Thus a solution of salts M+X¯
becomes a solution of acid H+X¯, the M+ ions being retained by the resin.
Subsequently a strongly basic form of an anion exchanger absorbs the X¯
ions and liberates OH¯ ions into water. These then neutralize the H+ ions
from the first step. The reslt is retention of all anions and cations and the
neutralization of H+ and OH¯ to form pure demineralization water.
• 2H+ (aq) + 2OH¯ (aq) ↔ 2H2O
49. 1. Cation exchanger –
(Polymer – SO3¯)2Ca²+ (s) + 2HCl ↔ 2(Polymer – SO3¯H+) (s) + Ca2Cl
2. Anionic exchanger –
2(Polymer – NR3+Cl¯) (s) + 2NaOH ↔ 2(Polymer – NR3+OH¯) (s) + 2NaCl
Regeneration of reagents:
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Wastewater
treatment -
removal parameters
The objectives of sewage treatment will always include
the reduction of the concentration of at least one of
the below constituents:
Suspended solids;
Organic (biodegradable) material;
Nutrients (nitrogen and phosphorous);
Pathogenic organisms (expressed as E. Coli)
Medicine residues, organic chemicals (POP´s)
Heavy metals
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Methods of Removal
The contaminants in wastewater are removed by different unit
processes:
Physical (sedimetation, flotation, screening, filtration)
Biological (trickling filters, RBC, activated sludge)
Chemical (chemical precipitation, ozonation, chlorination)
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Methods of Removal (Contd.)
Biological Unit Processes (mainly secondary)
The treatment method in which the removal of contaminants is brought
about by biological activity are known as biological unit process. Some
examples are:
• aerobic processes - presence of dissolved oxygen
• Biofilters
• Trickling filters
• Activated sludge
• anaerobic processes – absence of dissolved oxygen
• Denitrification (tertiary)
• Septic tanks
• Ponds
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Methods of Removal (Contd.)
Chemical Unit Process (tertiary)
Treatment methods in which the removal or conversion of contaminants
is brought about by the addition of chemicals or by chemical reactions
are known as chemical unit processes. Some of the most common are:
– Precipitation (lime, Fe- of Al salts, Struvite formation)
– Adsorption
– Disinfection
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Methods of Removal (Contd.)
Chemical Unit Process (tertiary)
Treatment methods in which the removal or conversion of contaminants
is brought about by the addition of chemicals or by chemical reactions
are known as chemical unit processes. Some of the most common are:
– Precipitation
– Adsorption (Ion exchange)
– Disinfection
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Methods of Removal (Contd.)
Chemical Unit Process (tertiary)
Treatment methods in which the removal or conversion of contaminants
is brought about by the addition of chemicals or by chemical reactions
are known as chemical unit processes. Some of the most common are:
– Precipitation
– Adsorption
– Disinfection (chlorination, UV-light, Ozone)
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Water and sludge treatment process at Bekkelaget
Primary sludge Buffertank
Buffer
Silo
Silo
Bio sludge
Dewatering
Thickener
Digester
Digester
Biogas
Overflow
Magasin~35.000m3
4000 l/s < Q < 6000 l/s
Sand, grit and
screenings FeSO4
PAX-18
Activated
sludge
Clarifier
Primary Filter
Precipitation
Primary
1900 l/s<Q< 4000 l/s
Q=1900 l/s
PAX-18
Q<1900 l/s
Biogas-
upgrading
80. Environmental Lagislations for Water in India
The Water (Prevention & Control) Act, 1974
(amended up to 1988).
A. The Water (Prevention & Control) Rules, 1975
and
B. The Water (Prevention & Control of Pollution) Cess
(Amendment) Act & Rules, 2003
The Water (Prevention & Control) Act, 1974
(amended up to 1991).
86. Control on Water Pollution
01
Prevent
Groundwater
contamination
02
Rather than
releasing sewage
waste into water
bodies, it is better
to treat them before
discharge.
03
Use the minimum
amount of
detergent and/or
bleach when you
are washing clothes
or dishes.
04
Minimize the use of
pesticides, herbicides,
fertilizers. DO NOT
dispose of these
chemicals, motor oil, or
other automotive fluids
into the water directly.
05
Avoid using a
garbage disposal.
Keep solid wastes
solid. Make a
compost pile from
vegetable scraps.
06
DO NOT pour fat
from cooking or
any other type of
fat, oil, or grease
into the water
07
DO NOT dispose of
household chemicals or
cleaning agents down
the sink or toilet.
87. Water Quality Management in India
135 litre per capita per day
Coastline
7500 km
Land Frontier 15,200 km
Climate - Topical
Population 135 Cr
Area 3.28 million sq. km
28 States and 9 Union
territories
Coordinates
80 4’ and 3706’ North latitudes
6807’ and 97025 East longitudes
India at a
Glance
88.
89.
90.
91.
92.
93.
94.
95.
96.
97.
98.
99.
100. Water is Precious and Scarce Resource
• India is one of the wettest country in the world, but rainfall is highly
uneven with time and space (with extremely low in Rajasthan and high in
North-East).
• On an average there are only 40 rainy days (100 hours).
• Out of 4000 BCM (Billion m3) rainfall received, about 600 BCM is put to
use so far.
• Water resources are over-exploited resulting in major WQ problems.
101. • Water quality monitoring in India started in 1978 under GEMS (Global
Environmental Monitoring System ) Program.
• National Program of Monitoring of Indian National Aquatic Resources started in 1984 with a total
of 120 stations in 10 River Basins.
• Present network comprising of 870 stations extended to 28 states & 9 Union Territories.
• Monitoring done or Quarterly/Monthly/Half Yearly basis.
• Monitoring network covers 189 Rivers, 53 Lakes, 4 Tanks, 2 Ponds, 3 Creeks, 3 Canals, 9 Drains
and 218 wells.
• Water samples are analyzed for 9 Core Parameters (pH, Temperature, Conductivity, DO, BOD,
Nitrite, Nitrate, Total Coliform and Faecal Coliform) for all monitoring. 19 General Parameters, 9
Toxic Metals and 15 Pesticides are also analyzed once in a year.
• Frequency of analysis for General Parameters reduced to once in a year in view of resources and
to add more stations in non-represented water-bodies. Frequency and Parameters does not
match the guidelines of GEMS. Base-line, Trend and Impact stations are maintained as per the
guidelines of GEMS.
NATIONAL WATER QUALITY MONITORING PROGRAMME
102. ISI Standards for water
01
Disposal of industrial
effluents into inland
surface water
02
Disposal of industrial
effluents into public
sewers
03
On land for irrigation
04
Tolerance limits for inland surface waters,
raw water, fish culture and irrigation
IS:
2490
IS:
3360
IS:
2296
IS:
3307
