This is a presentation which i made About the sources and the effects of ground water contamination. Along with pictures

1. GROUND WATER CONTAMINATION
USAGE OF FERTILIZERS AND PESTICIDES , ACID RAIN & ACID
DISCHARGE
SUFIYAN AHMED JEDDY
III-YR CIVIL-C
150011601105

2. WHAT IS GROUND WATER CONTAMINATION…?
Any addition of undesirable substances to groundwater
caused by human activities is considered to
be contamination.

3. SOURCE OF GROUNDWATER CONTAMINATION
Groundwater contaminants come from two categories of sources :
point sources and non-point sources

4. HOW DOES GROUND WATER CONTAMINATE??
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Infiltration from farm land treated with pesticides and fertilizers is an example of a non-point source.
Landfills, leaking gasoline storage tanks, leaking septic tanks, and accidental spills are examples of
point sources.
Several studies have documented the migration of contaminants from disposal or spill sites to
nearby lakes and rivers as this groundwater passes through the hydrologic cycle, but the processes
are not as yet well understood.
Septic systems are designed so that some of the sewage is degraded in the tank and some is
degraded and absorbed by the surrounding sand and subsoil.
Contaminants that may enter groundwater from septic systems include bacteria, viruses, detergents,
and household cleaners. These can create serious contamination problems.

5. GROUNDWATER CONTAMINATING ACTIVITIES

6. SOURCES OF GROUND
WATER
CONTAMINATION:

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There are many different sources of groundwater contamination.
Groundwater becomes contaminated when anthropogenic, or
people-created, substances are dissolved or mixed in waters
recharging the aquifer.
Examples of this are road salt, petroleum products leaking from
underground storage tanks, nitrates from the overuse of chemical
fertilizers or manure on farmland, excessive applications of
chemical pesticides, leaching of fluids from landfills and dumpsites,
and accidental spills.

8. CAUSES OF THESE GROUNDWATER
CONTAMINANTS
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Excess iron and manganese are the most common natural contaminants. Another form of
contamination results from the radioactive decay of uranium in bedrock, which creates the radioactive
gas radon.
Methane and other gases sometimes cause problems. Seawater can also seep into groundwater and
is a common problem in coastal areas. It is referred to as "saltwater intrusion".
These contaminants can originate from a “point source” or “non-point source” – meaning they can
come from a single source (or point) or, that they don’t have one specific source and come instead
from the cumulative effect of any number of factors or activities.

9. SOME MORE ABOUT SOURCES OF
GROUNDWATER CONTAMINATION
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POINT SOURCES
NON-POINT SOURCES

11. POINT SOURCES:
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On-site septic systems
Leaky tanks or pipelines containing petroleum products
Leaks or spills of industrial chemicals at manufacturing facilities
Underground injection wells (industrial waste)
Municipal landfills
Livestock wastes
Leaky sewer lines

12. NON POINT SOURCES:
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Fertilizers on agricultural land
Pesticides on agricultural land and forests
Contaminants in rain, snow, and dry atmospheric fallout

14. CONTAMINATION BY PESTICIDES
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Fertilization of surface waters, both as a result of direct discharges of manure and as a
consequence of nitrate, phosphate and potassium being leached from the soil.
Contamination of the groundwater as a result of leaching, especially by nitrate.
Phosphates are less readily leached out, but in areas where the soil is saturated with
phosphate this substance is found in the groundwater more and more often.
Surface waters and the groundwater are being contaminated by heavy metals. High
concentrations of these substances pose a threat to the health of man and animals.
To a certain extent these heavy metals accumulate in the soil, from which they are taken
up by crops. For example, pig manure contains significant quantities of copper.

16. CONTAMINATION BY ACID RAIN
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Acid rain is a rain or any other form of precipitation that is unusually acidic , meaning that it possesses
elevated levels of hydrogen ions (lowpH). It can have harmful effects on plants, aquatic animals and
infrastructure.
Acid rain is caused by emissions of sulfur dioxide and nitrogen oxide , which react with the water
molecules in the atmosphere to produce acids. Some governments have made efforts since the 1970s to
reduce the release of sulfur dioxide and nitrogen oxide into the atmosphere with positive results.
However, the extent to which acid rain contributes directly or indirectly via runoff from the catchment to
lake and river acidity (i.e., depending on characteristics of the surrounding watershed) is variable.
Both the lower pH and higher alumInium concentrations in surface water that occur as a result of acid rain
can cause damage to fish and other aquatic animals. At pHs lower than 5 most fish eggs will not hatch and
lower pHs can kill adult fish.

17. CONTAMINATION BY ACID MINE DRAINAGE
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Acid mine drainage, acid and metalliferous drainage (AMD), or acid rock drainage (ARD) is the outflow
of acidic water from metal mines or coal mines.
Areas where the earth has been disturbed (e.g. construction sites, subdivisions, and transportation
corridors) may create acid rock drainage.
In many localities, the liquid that drains from coal stocks, coal handling facilities, coal washeries, and
coal waste tips can be highly acidic, and in such cases it is treated as acid rock drainage.
The same type of chemical reactions and processes may occur through the disturbance of acid
sulphate soils formed under coastal or estuarine conditions after the last major sea level rise, and
constitutes a similar environmental hazard.

18. CONTAMINATION BY
ACID MINE DRAINAGE

20. THANK YOU…