soil pollution

1. TOPIC :
SOIL POLLUTION

2. INTRODUCTION:
 Soil is the thin layer of organic and inorganic materials that
covers the Earth's rocky surface. The organic portion, which is
derived from the decayed remains of plants and animals, is
concentrated in the dark uppermost topsoil. The inorganic
portion made up of rock fragments, was formed over
thousands of years by physical and chemical weathering of
bedrock. Soil is one of the important and valuable
resources of the nature. Life and living on the earth
would be impossible without healthy soil. 95% of
human food is derived from the earth.
Entrance of materials, biological organisms
or energy into the soil will cause changes
in soil quality.

3. Soil pollution is the addition of undesirable matter to the
land that damage the terrestrial organisms, reduce the
uses of the land by man for agricultural, residential,
recreational or other purposes or increase the risk of
health hazards to man.
Soil pollution is defined as the build-up in soils of
persistent toxic compounds, chemicals, salts,
radioactive materials, or disease causing agents, which
have adverse effects on plant growth and animal
health.
DEFINITION:

4. REASONS OF SOIL POLLUTION:
There are many different ways that soil can become polluted,
such as:
• Seepage from a landfill
• Discharge of industrial waste into the soil
• Percolation of contaminated water into the soil
• Rupture of underground storage tanks
• Excess application of pesticides, herbicides or fertilizer
• Solid waste seepage
The most common chemicals involved in causing soil pollution
are:
• Petroleum hydrocarbons
• Heavy metals
• Pesticides
• Solvents

5. TYPES OF SOIL POLLUTION:
• Agricultural Soil Pollution
i) pollution of surface soil
ii) pollution of underground soil
• Soil pollution by industrial effluents and solid wastes
i) pollution of surface soil
ii) disturbances in soil profile
• Pollution due to urban activities
i) pollution of surface soil
ii) pollution of underground soil

6. SOLID WASTE COMPOSITION

7. STATUS OF SOIL CONTAMINATION
• >125 major contaminated sites across the country
• 175 million hectare (out of 329 million ha) are considered
degraded
• > 40 % of chemical fertilizers leached into soil
• 14 States are affected by Fluoride contamination
• > 65 per cent of India’s villages are exposed to residual
pesticides risk
• garbage dumped in the ocean every year is roughly around
14 billion pounds.
• On a rough estimate Indian cities are producing solid city
wastes to the tune of 50,000 - 80,000 metric tons every day.

8. SOURCES OF SOIL POLLUTION:
• Agricultural sources:- These include waste matter produced by crop,
animal manure and farm residues, also pesticides, fertilizer and
insecticides.
• mining sources:- These includes piles of coal refuse and heaps of slag
and underground debris.
• industrial sources:- These includes paints, chemicals, metals and
plastics.
• sewage treatment:- Wastes that are left over after sewage has been
treated, biomass sludge and settled solids.
• deforestation:- Cutting down of trees for economics purposes.
•.construction sources:- Waste like debris, wood, metals and plastics.

9. Sources of soil
pollution

10. CAUSES OF SOIL POLLUTION
• Polluted water discharged from factories
• Runoff from pollutants (paint, chemicals, rotting organic
material) leaching out of landfill
• Oil and petroleum leaks from vehicles washed off the road by
the rain into the surrounding habitat.
• Chemical fertilizer runoff from farms and crops
• Acid rain (fumes from factories mixing with rain)
• Sewage discharged into rivers instead of being treated properly
• Over application of pesticides and fertilizers
• Purposeful injection into groundwater as a disposal method
• Septic tank seepage
• Lagoon seepage
• Sanitary/hazardous landfill seepage
• Cemeteries
• Leaks from sanitary sewers

11. POLLUTION IN SOIL IS ASSOCIATED WITH
• Indiscriminate use of fertilizers: {ammonium nitrate
(NH4NO3),phosphorus as P2O5, and potassium as K2O}
• Indiscriminate use of pesticides, insecticides and herbicides: {DDT
(dichlorodiphenyltrichloroethane),chlorinated hydrocarbons,
organophosphates, malathion, dieldrin, furodan, etc.}
• Dumping of large quantities of solid waste {In general, solid
waste includes garbage, domestic refuse and discarded solid
materials such as those from commercial, industrial and
agricultural operations. They contain increasing amounts of paper,
cardboards, plastics, glass, old construction material, packaging
material and toxic or substances.}
• Deforestation and soil erosion

12. SOIL POLLUTANT:
A soil pollutant is any factor which deteriorates the quality,
texture and mineral content of the soil or which disturbs the
biological balance of the organisms in the soil. Pollution in soil
has adverse effect on plant growth
Pesticide pollution
These include pesticides, herbicides, insecticides, fungicides
and others.
• Pesticides applied on seed or foliage ultimately reach the soil.
• Accumulation of pesticide residues in the biosphere creates
ecological stress causing contamination of soil, water, and food.
• Persisting chemicals may also be hazardous to human health
and should be eliminated.
• Persistent pesticides may accumulate in the bodies of animals
and over a period of time increase in concentration if the animal
is unable to flush leading to bioaccumulation

13. Fertilizer pollution
• The agricultural production depends on chemical fertilizer
application, as most of our high yielding varieties are fertilizer
responsive.
• Continuous application of chemical fertilizers alone lead to
deterioration of soil properties and cultivated soils loose their
natural characteristics.
• Fertilizers like ammonium sulphate, ammonium chloride and
urea reduce the soil pH.
• Many crops, like potato, grapes, citrus, beans are sensitive to
chloride toxicity.
• In integrated nutrient management,
to sustain the productivity of our soils,
organic manures and bio fertilizers are
recommended as supplements to chemical
fertilizers.

14. Nitrate pollution
• The four forms of nitrogen that are of particular significance in
environmental technology are organic nitrogen, ammonia
nitrogen, nitrite nitrogen, and nitrate nitrogen.
• In water contaminated with sewage, most of the nitrogen is
originally present in the form of complex organic molecules
(protein) and ammonia (NH3). These substances are eventually
broken down by microbes to form nitrites and nitrates.
• Excessive nitrate concentrations in surface waters encourage
the rapid growth of microscopic plants called algae and excessive
growth of algae degrades water quality.
• Excessive nitrate concentrations in drinking water pose an
immediate and serious health threat to infants under 3 months of
age.

15. Excess Salts and Water
• Irrigation water contains dissolved salts and in dry
season, water is in the form of saline solution
evaporates leaving its salts such as NaCl in the top soil.
• This saline soil causes stunted plant growth, lower
yield.
• Flushing out salts reduces the salinity but makes
downstream irrigation water, saltier.
• water logging.
Heavy metal pollution
• Heavy metals include all metals with atomic numbers
greater than 23 (with few exceptions) (eg. Hg, 70 gm ml-1).
• They are toxic to man and other life forms.
• Most of them are slow poisons as they accumulate in the
body and cause serious disorders.
• Mercury, lead, arsenic, chromium and cadmium are the five
most common toxic heavy metals and they have serious
effects on human health .

16. .
Heavy metal (forms) Source Effect
Mercury – Hg++ Methyl mercury
fungicides, electrical and
electronic industries,
PVC, plastics, paints
Irreversible neurological
damage in man,
Minamata disease
Lead - Pb2+ , Pb4+ Automobile exhaust of
leaded petrol, batteries,
pipes, soldering
Mutation in algae and
bacteria, blackening in
fish, gradual paralysis in
man
Arsenic – As++,
Arsenic trioxide,
Sodium arsenate
Herbicide, fungicide,
wood preservative –
Agrochemicals (70%),
paints, bullets (20%),
glass wares (5%)
Accumulate in hair, nail,
skin lesions, act as
oxidative uncoupler,
damage to kidney,
respiratory and nervous
disorders

17. Detergents:
Existence of detergents in sewage will increase soil
permeability and microorganisms and even molecules, which
cannot pass ordinarily from soil filters, will able to pass from
pores of consecutive and different layers of soil in the
presence of detergents and can cause microbial
contamination of the waters which are placed in a relatively
high
distance to the ground levelOil Pollution
It is for a long time that oil materials and its derivatives cause
soil pollution as a result of transportation or storage. Oil pollution
is an inevitable outcome as a result of rapid population growth
and industrialization process, based on which, soil pollution can
be observed by oil hydrocarbon materials vastly around
exploration and refining installations typically via transfer of
these materials. In addition to the direct emission of these
pollutants, dusts of burning gases along with oil have managed
to add toxic and harmful substances to the soils of the region for

18. Plastics
Plastics form a major part of global domestic and industrial
waste. Not being biodegradable, waste plastic accumulates,
adding to pollution. Using photodegradable plastic or
biodegradable plastic can solve plastic pollution problem.
Photodegradable plastic contains an element sensitive to
UV rays. Under the effect of solar rays the element is
activated and breaks the polymeric chain of the
photodegradable plastic. It results in small fragments that
are easily digested by microbes.

19. EFFECTS OF SOIL POLLUTION
Agricultural
• Reduced soil fertility and nitrogen fixation.
• Increased erodibility
• Larger loss of soil and nutrients
• Deposition of silt in tanks and reservoirs
• Reduced crop yield
• Imbalance in soil fauna and flora
Industrial
• Dangerous chemicals entering underground water
• Ecological imbalance
• Release of pollutant gases
• Release of radioactive rays causing health problems
• Increased salinity
• Reduced vegetation
Urban
• Clogging of drains
• Inundation of areas
• Public health problems
• Pollution of drinking water sources
• Foul smell and release of gases

20. ENVIRONMENTAL LONG TERM EFFECTS OF SOIL
POLLUTION• When it comes to the environment itself, the toll of contaminated soil is
even more dire.
• Soil that has been contaminated should no longer be used to grow food,
because the chemicals can leech into the food and harm people who eat it.
• If contaminated soil is used to grow food, the land will usually produce
lower yields than it would if it were not contaminated.
• it can cause even more harm because a lack of plants on the soil will
cause more erosion, spreading the contaminants onto land that might not
have been tainted before.
• In addition, the pollutants will change the makeup of the soil and the types
of microorganisms that will live in it.
• If certain organisms die off in the area, the larger predator animals will also
have to move away or die because they've lost their food supply. Thus it's
possible for soil pollution to change whole ecosystems

21. CONTROL OF SOIL POLLUTION
The following steps have been suggested to control soil pollution.
To help prevent soil erosion, we can limit construction in sensitive
area. By following the three R's: Reduce, Reuse, and Recycle.
Reducing chemical fertilizer and pesticide use
Applying bio-fertilizers and manures can reduce chemical fertilizer
and pesticide use.
Biological methods of pest control can also reduce the use of
pesticides and thereby minimize soil pollution.
Reusing of materials
Materials such as glass containers, plastic bags, paper, cloth etc.
can be reused at domestic levels rather than being disposed,
reducing solid waste pollution.

22. Recycling and recovery of materials
This is a reasonable solution for reducing soil pollution.
Materials such as paper, some kinds of plastics and glass can
and are being recycled. This decreases the volume of refuse
and helps in the
conservation of natural resources. For example, recovery of one
tonne of paper can save 17 trees.
Reforesting
Control of land loss and soil erosion can be attempted through
restoring forest and grass cover to check wastelands, soil
erosion and floods. Crop rotation or mixed cropping can
improve the fertility
of the land.
.

23. METHODS TO CONTROL SOIL POLLUTION:
SOIL WASHING:
 Soil washing is a mechanical process that uses liquids, usually water, to
remove chemical pollutants from soils.
 The purpose of soil washing is to first, separate the fine silt and clay
particles from the coarser sand and gravel particles and then to facilitate
the transfer of these chemical contaminants from the soil surface to the
water, which can then be further treated.
 The first step of the process is to excavate the contaminated soil and
move it to a staging area where it is prepared for treatment
 The soil is then sieved to remove debris and large objects, such as rocks,
which can be disposed of on site, if free of contamination. The remaining
smaller-sized soil material enters a soil-washing unit, in which the soil is
mixed with a washing solution and agitated. After the wash-water is drained
from the washed soil, the soil is rinsed with clean water

24. EPA MOBILE SOIL-WASHING SYSTEM
Feed Soil
Wash Water
Coarse Fraction
Chemical Additives
Clean Water
Clean
Product
Hydrocyclones
Drum Washer
Trommel
Fine Fraction
Stirred
Tank
Stirred
Tank
Stirred
Tank
Stirred
Tank
Contaminant + water

25. LAND FARMING:
• Land spreading (also known as land farming, land disposal and
land treatment)
• Land farming is a form of bioremediation (It is a waste
management technique that involve the use of organisms to
remove pollutant.), which allows the soil's naturally occurring
microbial population to degrade drilling waste constituents
(particularly hydrocarbons, other organic compounds and
nitrogen).• Land farming can transform contaminants into non-hazardous
substances.
Tilling of strip as part of landfarming
Watering of strip as part of land
farming

26. Each strip is recorded by
marking the date of spreading &
treatment applied
This technology usually involves
spreading contaminated soils in
a thin layer on the ground
surface and stimulating aerobic
microbial activity within the soils
through aeration and/or the
addition of minerals, nutrients,
and moisture
.
Each strip shall be clearly
marked on a board, by the
Contractor, with the following
information::
 Date of spreading
 Treatment applied
The effectiveness of
landfarming depends on
parameters that may be
grouped into four categories:
• soil characteristics
• constituent characteristics
• climatic conditions
• Soil texture which may
affects moisture content, and
bulk density of the soil

27. SOIL POLLUTION CONTROL TECHNIQUE:
1. Controlling Oil Pollutions in Soil
1. Preventing oil from spreading widely,
2. Improve the soil ventilation through plowing and mixing,
3. Increasing food nutrients to the soil like nitrogen and phosphor,
4. Combining soil with microorganisms which decompose oil
materials2. Controlling Pollutions Caused by Waste in soil
1. Application of effective technology for dumping waste like
compressing and covering of openings and holes,
2. Dumping waste higher than the highest underground water levels,
3. Creating impenetrable layers in building of land fields
4. Creating drainage system for the collection of leachates
5. Using the gases produced in land fields.
3.Controlling Pollution Caused by Industrial Activities in Soil
1. Soil can be excavated up to the specified depth and the excavated
soil can be taken away from the region and then, it can be restored.
2.The soil can be restored at the same area.
3.Keeping soil in the area is the other method. Under such
circumstances, auxiliaries are added to the soil to prevent
spread of infection to the plants, animals and human

28. 4. Solid waste treatment
Proper methods should be adopted for management of
solid waste disposal. Industrial wastes can be treated
physically, chemically and biologically until they are less
hazardous. Acidic and alkaline wastes should be first
neutralized; the insoluble material if biodegradable should
be allowed to degrade under controlled conditions before
being disposed

29. REFERENCES:
• (http://scholarsresearchlibrary.com/archive.html)
• Bavandi, Bijan, Ecosystem, Publications of the
Department of the Environment (DoE), 1975
• soil pollution by Dinesh Mani, S.G Misra
• soil pollution wikipedia