MODULE 4

ACID RAIN
Rain water p H is around 5.7 due to certain concentration of CO 2 dissolved as rainwater trickles
down atmosphere, i.e. CO 2+H2O→HCO3-+H+

Acid rain is defined as any type of precipitation with a p H that is unusually low. Dissolved carbon
dioxide dissociates to form weak carbonic acid giving a p H of approximately 5.6 at typical
atmospheric concentrations of CO2. Therefore a p H of less than 5.6 has sometimes been used as a
definition of acid rain.

Acid rain was first found in Manchester, England. In 1852, Robert Angus Smith found the
relationship between acid rain and atmospheric pollution. Though acid rain was discovered in
1852, it wasn't until the late 1960s that scientists began widely observing and studying the
phenomenon.

Causes
The principal natural phenomena that contribute acid-producing gases to the atmosphere are
emissions from volcanoes and those from biological processes that occur on the land, in wetlands,
and in the oceans. The major biological source of sulfur containing compounds is dimethyl sulfide.

The principal cause of acid rain is sulfuric and nitrogen compounds from human sources, such as
electricity generation, factories and motor vehicles. Coal power plants are one of the most
polluting. The gases can be carried hundreds of kilometres in the atmosphere before they are
converted to acids and deposited. Factories used to have short funnels to let out smoke, but this
caused many problems, so now, factories have longer smoke funnels. The problem with this is
those pollutants get carried far off, where it creates more destruction.

Sulfur dioxide contributes to about seventy percent of acid rain while nitrogen oxides provide the
remaining thirty percent. The sources of sulfur in the atmosphere include coal combustion,
smelting, organic decay, and ocean spray. Approximately ninety percent of atmospheric sulfur
results from human activities.

In the atmosphere, sulfur dioxide combines with water vapor to form hydrogen sulfite gas: SO 2 +
H2O+1/2O2 → H2SO4

Next, hydrogen sulfite reacts with oxygen to form sulfuric acid, a major component of acid rain:
H2SO3 + 1/2O2 → H2SO4

The sources of nitrogen oxides include the combustion of oil, coal and natural gas, forest fires,
bacterial action in soil, volcanic gases, and lighting-induced atmospheric reactions.
In the atmosphere, nitrogen monoxide reacts with oxygen gas to form nitrogen dioxide gas: NO
+ 1/2O2 → NO2

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 68

 Then, nitrogen dioxide reacts with water vapor in the atmosphere to form hydrogen nitrite and
hydrogen nitrate: 2NO 2 + H2O → HNO2 + HNO3

Henceforth, acid rain is a mixture of HNO 3, H2SO4 + HCl. however conditions needed to favor
formation of these are sunlight, temperature, humidity, hydrocarbons, NO X, SO2.

Effects
Both the lower p H and higher aluminum concentrations in surface water that occur as a result of
acid rain can cause damage to fish and other aquatic animals. At p H lower than 5 most fish eggs
will not hatch and lower p H can kill adult fish. As lakes become more acidic biodiversity is reduced.
Soil biology can be seriously damaged by acid rain. Some tropical microbes can quickly consume
acids but other microbes are unable to tolerate low p H and are killed.

Acid rain can slow the growth of forests, cause leaves and needles to turn brown and fall off and
die. In extreme cases trees or whole areas of forest can die. The death of trees is not usually a direct
result of acid rain; often it weakens trees and makes them more susceptible to other threats.

Some scientists have suggested direct links to human health, but none have been proven. However,
fine particles, a large fraction of which are formed from the same gases as acid rain (sulfur dioxide
and nitrogen dioxide), have been shown to cause illness and premature deaths such as cancer and
other deadly diseases

Toxic metals released into the environment by acid rain may enter water supplies or accumulate in
fish and crops. Acid deposition also destroys statues, headstones, buildings, and fountains.
Limestone structures are especially susceptible because they dissolve easily in acidic solutions.

Acid rain can also cause damage to certain building materials and historical monuments. Acid rain
can cause weathering on ancient and valuable statues and has caused considerable damage. This
is because the sulfuric acid in the rain chemically reacts with the calcium compounds in the stones
(limestone, sandstone, marble and granite) to create gypsum, which then flakes off. Acid rain also
causes an increased rate of oxidation for iron.

Control Measures
➢ Design more efficient automobile engines in order to reduce nitrogen oxide emissions.
➢ Increase efficiency of power plants that burn coal in order to reduce waste that contains
sulfur dioxide and nitrogen oxide.
➢ Increase penalties on industries that do not meet air pollution guidelines.
➢ Increase tax incentives to industries that do meet guidelines.
➢ Use alternative energy sources, Increase funding for alternative energy sources; for
example, give tax incentives to buyers of hybrid cars.
➢ Provide tax incentives to companies that use alternative energy sources.
➢ Add CaCO3 (calcium carbonate) to lakes suffering from acid deposition; calcium carbonate
acts as a buffer, resisting a change in p H and lessening the negative effects of acid rain.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 69

 OZONE DEPLETION
Definition

Ozone layer is an umbrella 24 km [15 miles] from earth surface, an essential component of the
stratosphere that absorbs short wavelength ultraviolet radiation from the sun, heating the gases of
the stratosphere in the process. This is the reason temperatures rise with increasing altitude in the
stratosphere, and also the reason life was able to move out of the oceans and on to the land, evolving
into the diverse biosphere we know today.

World ozone day is celebrated on Sept, 16 of every year. Stratospheric ozone is measured in
Dobson units [DU] named after G.M.B Dobson who pioneered the study; [I Dobson unit = 0.01
mm thickness of stratospheric ozone], Average ozone thickness in stratosph ere is 300 DU, & when
it falls below 200 DU, it’s considered as Ozone hole. It is thinnest around equator and thickest near
poles.

Stratospheric ozone depletion is the term applied to the loss of stratospheric ozone molecules (O3)
and the disruption of Oxygen-Ozone concentration equilibrium in stratosphere [i.e., when chlorine
atoms upset the natural O2/O3 equilibrium in the stratosphere]. Oxygen molecules interact with the
intense solar radiation present at this elevation to form oxygen atoms. The oxygen atoms thus
generated react with other oxygen molecules to form ozone (O3).

Causes
Ozone depletion is caused by the release of chlorofluorocarbons (CFC's) and other ozone-
depleting substances (ODS), which were used widely as refrigerants, insulating foams, and
solvents. The discussion below focuses on CFCs, but is relevant to all ODS [N O, NO2 (aircraft
exhaust), Br-, UV rays, [O] Atomic oxygen etc.].

Although CFCs are heavier than air, they are eventually carried into the stratosphere in a process
that can take as long as 2 to 5 years. It can be recalled that commercial airliners [sub -sonic] fly in
lower stratosphere, jet airliners [super-sonic] fly in the troposphere

When CFCs reach the stratosphere, the ultraviolet radiation from the sun causes them to break
apart and release chlorine atoms which react with ozone, starting chemical cycles of ozone
destruction that deplete the ozone layer. One chlorine atom can break a part more than 100,000
ozone molecules.

Other chemicals that damage the ozone layer include methyl bromide (used as a pesticide), halons
(used in fire extinguishers), and methyl chloroform (used as a solvent in industrial processes). As
methyl bromide and halons are broken apart, they release bromine atoms, which are 40 times more
destructive to ozone molecules than chlorine atoms.

While it is true that volcanoes and oceans release large amounts of chlorine, the chlorine from
these sources is easily dissolved in water and washes out of the atmosphere in rain. In contrast,
CFCs are not broken down in the lower atmosphere and do not dissolve in water.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 70

 The chlorine in these human-made molecules does reach the stratosphere. Measurements show that
the increase in stratospheric chlorine since 1985 matches the amount released from CFCs and other
ozone-depleting substances produced and released by human activities.

The Chapman Cycle

Chlorofluorocarbons, or CFC’s, are inert molecules that are not removed in the
troposphere. They have residence times of over a hundred years and ultimately
diffuse through the troposphere to the stratosphere. In the stratosphere CFC’s are
exposed to the intense solar radiation that cannot penetrate the ozone layer, and the
CFC’s become photo chemically active. The result is the production of chlorine
atoms and chlorine oxide molecules, two substances that behave very much like
nitrogen oxide in t h e unperturbed atmosphere.

Ozone Depletion by CFC’s

All above reactions occur in the presence of UV rays, while the 2 nd set of reactions governs the
oxygen-ozone equilibrium due to its spontaneity.

Effects
Effect of ozone hole include cataract, genetic mutation, constriction of blood vessels, reduced crop
yield, leukemia, breast cancer, damage to crop, aqua culture, etc.,

The higher energy UV radiation absorbed by ozone is generally accepted to be a contrib utory
factor to skin cancer. In addition, increased surface UV leads to increased tropospheric ozone,
which is a health risk to humans. The increased surface UV also represents an increase in the
vitamin D synthetic capacity of the sunlight.

It should be deduced that the above impacts are not due to exposure of Ozone but due to the UV
rays that have reached the earth surface through the ozone holes. One important health hazard is
Snow Blindness [photo keratosis], i.e., inflammation of cornea (outer coating of eyeball).

The most common forms of skin cancer in humans, basal and squamous cell carcinomas have been
strongly linked to UVB exposure. Another form of skin cancer, malignant melanoma, is much less
common but far more dangerous, being lethal in about 15% - 20% of the cases diagnosed.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 71

 Presence of ozone causes plants to close their stomata, a defence mechanism that bloc ks out CO 2
as well inhibiting photosynthesis and respiration. Gross productivity to conduct photosynthesis will
decrease at least by 14-23% due to this. In India there is no standard for Ozone. However WHO
standard is 100 ppm for 8 hrs – avg.

Control Measures
The results of 18-year study of the ozone column over Antarctica [1 st spotted, 1979] showing that
the ozone column had decreased from 1957 to 1985, a 35% decrease.

This report led through several regulatory steps to the Montreal Protocol, an international
agreement signed by 139 nations, banning the production of CFCs by the year 2000.

In 1978, the use of CFC propellants in spray cans was banned in the U.S. In the 1980s, the Antarctic
"ozone hole" appeared and an international science assessment more strongly linked the release of
CFCs and ozone depletion. It became evident that a stronger worldwide response was needed.

In 1987, the Montreal Protocol was signed and the signatory nations committed themselves to a
reduction in the use of CFCs and other ozone-depleting substances. Since that time, the treaty has
been amended to ban CFC production after 1995 in the developed countries, and later in
developing. Today, over 160 countries have signed the treaty.

We can't make enough ozone to replace what's been destroyed, but provided that we stop producing
ozone-depleting substances, natural ozone production reactions should return the ozone layer to
normal levels by about 2050.

It is very important that the world comply with the Montreal Protocol; delays in ending production
could result in additional damage and prolong the ozone layer's recovery.

Control mechanism stresses on replacement of the banned chemical by ammonia, steam, helium
etc.

GREEN HOUSE EFFECT

Objects that absorb all radiation upon them are called "blackbody" absorbers. The earth is close to
being a black body absorber. Gases, on the other hand, are selective in their absorption
characteristics.
While many gases do not absorb radiation at all some selectively absorb only at certain
wavelengths. Those gases that are "selective absorbers" of solar energy are the gases we know as
"Greenhouse Gases." The greenhouse effect is a phenomenon that ought to create a condition in
the upper atmosphere, causing a trapping of excess heat and leading to increased surface
temperatures.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 72

 The Earth receives energy from the Sun in the form of radiation. The Earth reflects about 30% of
the incident solar flux; the remaining 70% is absorbed, warming the land, atmosphere and oceans.

The visible solar radiation heats the surface, not the atmosp here, whereas most of the infrared
radiation escaping to space is emitted from the upper atmosphere, not the surface.

The infrared photons emitted by the surface are mostly absorbed by the atmosphere and do not
escape directly to space. Hence earth’s greenhouse effect is a natural phenomenon that helps
regulates the temperature of our planet. Simply put, the sun heats the earth and some of this heat,
rather than escaping back to space, is trapped in the atmosphere by clouds and greenhouse gases,
such as water vapor and carbon di oxide. If all these greenhouse gases were to suddenly disappear,
our planet would be 60° F colder and uninhabitable.

The steady state condition of earth is disrupted by the presence of the excess
greenhouse gasses. The solar radiations strike as ultra violet with long wavelength
but on reflection they pare infrared with shorter wavelengths.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 73

 On Earth, the major natural greenhouse gases are water vapor, which causes about 36 –70% of the
greenhouse effect (not including clouds); carbon dioxide (CO 2), which causes 9–26%; methane
(CH4), which causes 4–9%; and ozone, which causes 3–7%. The greenhouse gases [carbon-di-
oxide, methane etc.,] traps these radiations preventing their reflection or escape back to atmosphere
and this results in warming of land surface. Hence it’s a natural phenomenon.

Hence excessive concentration of these gases resulting from natural or man -made activities
building up in drastic proportions leads to greenhouse effect.

Carbon Dioxide

Sources: Released by the combustion of fossil fuels (oil, coal, and natural gas), fla ring of
natural gas, changes in land use (deforestation, burning and clearing land for agricultural
purposes), and manufacturing of cement.
Sinks: Photosynthesis and deposition to the ocean.
Significance: Accounts for about half of all warming potential caused by human activity.

Methane

Sources: Landfills, wetlands and bogs, domestic livestock, coal mining, wet rice growing,
natural gas pipeline leaks, biomass burning, and termites.
Sinks: Chemical reactions in the atmosphere.
Significance: Molecule for molecule, methane traps heat 20-30 times more efficiently
than CO2. Within 50 years it could become the most significant greenhouse gas.

Nitrous Oxide [296 times potential than CO2]

Sources: Burning of coal and wood, as well as soil microbes' digestion.
Sinks: Chemical reactions in the atmosphere.
Significance: Long-lasting gas that eventually reaches the stratosphere where it
participates in ozone destruction.

Ozone

Sources: Not emitted directly, ozone is formed in the atmosphere through photochemical
reactions involving nitrogen oxides and hydrocarbons in the presence of sunlight.
Sinks: Deposition to the surface, chemical reactions in the atmosphere.
Significance: In the troposphere ozone is a pollutant. In the stratosphere it absorbs
hazardous ultraviolet radiation.

Chlorofluorocarbons (CFCs)

Sources: Used for many years in refrigerators, automobile air conditioners, solvents,
aerosol propellants and insulation.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 74

 Sinks: Degradation occurs in the upper atmosphere at the expenses of the ozone layer.
One CFC molecule can initiate the destruction of as many as 100,000 ozone molecules.
Significance: The most powerful of greenhouse gases — in the atmosphere one molecule
of CFC has about 20,000 times the heat trapping power on a molecule of CO2 .

Another important feedback process is ICE-ALBEDO FEEDBACK. The increased CO 2 in the

atmosphere warms the Earth's surface and leads to melting of ice near the poles. As the ice melts,
land or open water takes its place. Both land and open water are on average less reflective than ice,
and thus absorb more solar radiation. This causes more warming, which in turn causes more
melting, and this cycle continues. This enhances sea level rise, coastal zone submergence, and
malaria outbreaks and of course ice cap melting. Control measures include planting more trees,
reducing vehicular emission and thermal stacks, and elimination of volatile organic compounds.

CLIMATE CHANGE
Global warming is the increase in the average temperature of the Earth's near-surface air and oceans
in recent decades and its projected continuation. Global average air temperature near the Earth's
surface rose to 0.74 ± 0.18 °C (1.3 ± 0.32 °F) during the past century.

In the Arctic, average temperatures have risen almost twice as fast as in the rest of the world and
climate changes are particularly intense.

Other consequences may include changes in agricultural yields, glacier retreat, reduced summer
stream flows, species extinctions and increases in the ranges of disease vectors.

The melting of Arctic ice and increased regional precipitation can add freshwater to the oceans,
and potentially affect ocean currents in the North Atlantic.

Melt of glaciers can contribute to sea level rise: By 2100, melting of Arctic glaciers alone will have
contributed to a sea level rise of roughly 5 cm out of the projected 10 -90 cm total rise for this
century.

Forest fires could become more frequent, Due to the warming; insect outbreaks will increasingly
disturb large areas of forest. Most scenarios project more forest fires in all ecosystems.

Polar Bears depend on sea ice for their survival: Many Arctic animals, such as polar bears, seals,
walruses, and seabirds, rely on the sea’s biological productivity and on the presence of sea ice,
both of which are highly dependent on climatic conditions.

Changes in sea surface temperatures or currents could have a strong effect on Arctic marine fish
stocks, which are an important food source for the world and play a vital role in the region’s
economy.

Rising temperatures are modifying the Arctic coastline and are expected to change it even more in
the future. Sea level rise is likely to cause flooding of marshes and coastal plains and accelerate
beach erosion. Some towns and industrial facilities are already suffering severe damage as a result
of erosion, and are now facing the prospect of relocation.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 75

 More specifically, eleven of the last twelve years (1995-2006) rank among the 12 warmest years
ever recorded since global surface temperatures are measured (1850). Over the last 100 years
(1906–2005), global temperature has increased by 0.74°C. Bangalore f aced the wettest March in
133 years

Other projected changes include acidification of the oceans, reduced snow cover and sea ice, more
frequent heat waves and heavy precipitation, more intense tropical cyclones, and slower oceanic
currents.

Warming and sea level rise caused by human activities will continue for centuries, even if
greenhouse gas concentrations were to be stabilized. If warming persists over many centuries, it
could lead to a complete melting of the Greenland Ice sheet, increasing global sea levels by about
7m.

Additional anticipated effects include 18% to 35% of a sample of 1,103 animal and plant species
to be extinct by 2050, based on future climate projections.

The world's primary international agreement on combating global warming is the Kyoto Protocol,
an amendment to the United Nations Framework Convention on Climate Change (UNFCCC),
negotiated in 1997. The Protocol now covers more than 160 countries globally and over 55% of
global greenhouse gas (GHG) emissions.

How to Prevent Global Warming

Use Compact Fluorescent Bulbs Change Your Air Filter
Use Recycled Paper Check Your Water Heater
Use Solar-heated Water Change the AC Filter
Take Shorter Showers Install a Low-Flow
Showerhead

Buy Products Locally Buy Minimally Packaged

Goods
Buy a Hybrid Car, Bio-fuel driven Buy a Fuel Efficient Car,
Carpool When You Can Reduce Garbage
Plant a Tree Buy Organic Food
Replace Old Appliances Use a Push Mower

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 76

 Unplug Un-Used Electronics Air Dry Your Clothes

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 77

 Insulate Your Home Switch to Double Pane Windows
Bring Cloth Bags to the Market & Turn off Your Computer Whenever Possible

FLUORIDE PROBLEM IN DRINKING WATER [MPL = 1.0 ppm]

Fluorine, one of the most active halogens/elements is not used in its elemental form in
environmental engineering, principle forms in which fluorine are added to public water supply
include NaF, CaF2, HF, Na2SiF6, H2SiF6 & (NH4)2SiF6. All compounds containing fluorine
disassociate to form fluoride ions. F-.

Determination of fluoride concentration is carried out by ion chromatography, electrode,

colorimetric & SPADNS method.

Environmental engineer has a dual interest in F- concentration in water supply schemes…

1. Design, operate units for removal of excessiveconcentration.

2. Ensure the minimum / optimum concentration to be present (1ppm).

Sources of F- contamination include Alumunium Processing Plants. In aluminum units, cryolite

[Na3AlF6] used as solvent f or Al2O3 in electrolytic method of aluminum. At operating
temperature, cryolite is molten hence F- escapes to atmosphere as vapor.

Excess F- Removal techniques i.e., Defluoridation involves passing water through Defluoridation
media like activated alumina, bone char by combination of processes of sorption and ion exchange.

Extreme limits of F- > 4ppm causes crippling skeletal fluorosis, 4 < x > 2 ppm causes dental
fluorosis, while < 1 ppm causes dental carries. Fluoride does not concentrate in any tissues but
only in bones and teeth.

Dental carries is a medical condition in which a human or any organism lacks necessary
compounds containing F- to keep bones and teeth healthy. Symptoms include yellow coloring of
teeth, white flecks , small pits in enamel of teeth, severe case also displays brown stains.

The most widely accepted adverse effect of low concentration fluoridation at this time is fluorosis.
It is a condition caused by 'excessive' intake of fluorine compounds over an extended period of time,
and can cause yellowing of teeth. The definition of 'excessive' in the context of fluorosis falls on
the order of parts per million and is generally accepted to mean significantly higher than the 0.7 to
1.2 ppm amounts recommended for fluoridated water. Excessive fluoride has been scientifically
linked to liver damage, kidney function, and fluorosis in children.

Although it is usually the permanent teeth which are affected, occasionally the primary teeth may
be involved. In mild cases, there may be a few white flecks or small pits on the enamel of the teeth.
In more severe cases, there may be brown stains.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 78

 Fluoride ions replace hydroxide ions in calcium hydroxyapatite, Ca 5[(PO4)3OH], in teeth, forming
calcium fluoroapatite, Ca 5[(PO4)3F], which is more chemically stable and dissolves at a pH of 4.5,
compared to 5.5 pH for calcium hydroxy patite. This is generally believed to lead to fewer cavities,
since stronger acids are needed to attack the tooth enamel.

RESETTLEMENT AND REHABILITATION OF PEOPLE

Major projects such as dams, mining or the notification of a National Park disrupt the lives of the
people who live there and may also require their moving permanently to an alternative site. None
would like to give up the home they grow up in. Uprooting people is a serious issue. When dams
are constructed in populated areas, many tribal are compelled by government and forced to relocate
without adequate or no compensation. The Governments promises to find ‘good’ arable land to
resettle displaced persons and provide them with an adequate rehabilitation package to recover
from the disruption has rarely occurred to the satisfaction of the project affected individuals.

Resettlement and Rehabilitation of People reduces the ability of residents to subsist on their
traditional natural resource base and also creates great psychological pressures. Tribal whose lives
are woven closely around their own natural resources, cannot adapt to a new way of life in a new
place. Established communities get dispersed and are often destroyed. The communities that are
forced to absorb the influx of displaced tribal are as well strained to their maximum capacity. The
cost of moving often leaves the tribal poorer than before. Due to space and resource constraints,
tribal are often forced to move long distances from their original homes. This, coupled with the
hard transition into urban areas, often destroys traditional cultures. The Projects severely affected
people's economic security as many receive little or no compensation for their land lost, and no
compensation was given for other resources destroyed by the project. For those who are supposed
to be covered under the resettlement and rehabilitation program, they are prone to many forms of
economic victimization. In India several lakhs of people have been unfairly displaced by dam
projects created since independence. The dams have been built virtually at the cost of the poor local
people who have been powerless to resist the Government.

The Governments promises to find ‘good’ arable land to resettle displaced persons and provide
them with an adequate rehabilitation package to recover from the disruption has rarely occurred to
the satisfaction of the project affected individuals. Resettlement requires alternate land to be
provided to the people. In our overpopulated country as there is no arable high quality land
available, most times project affected persons are given unusable wasteland. There is also emotional
and psychological trauma caused by forcibly removing people from their homeland where their
families have lived for centuries. There are also situations when communities request for shifting
to a new site. This is often observed when people live inside or on the periphery of a National Park
or Wildlife Sanctuary. The Tehri Dam project in the outer Himalayas in Uttar Pradesh, when
finished will submerge Tehri town and nearly another 100 villages. Little has been done to ensure
proper rehabilitation and compensation for nearly a lakh of people who will be uprooted from their
homes as a result of this dam, with little hope of rehabilitation, as no alternative land is available.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 79

 Figure: Public Protest due to inadequate Resettlement and Rehabilitation.

MODULE 5

Introduction to G.I.S. & Remote Sensing

G.I.S. or Geographical Information System (GIS) basically deals with information pertaining to
spatial objects or features which can be referred or related to a specific location on the Earth’s
surface. While the objects may be natural or manmade; information deals with large volume of
data relative to it on the earth’s surface, and comprises of its qualitative and quantitative aspects.
G.I.S. hence can be defined as a system which provides a computerized mechanism for integrating
various geo-information datasets and analyzing them in order to generate information relevant to
planning needs. Keeping long tradition of map-making as background, G.I.S. has been developed
during mid-20 th century with the development of Computer Science. The first time operational
G.I.S. was developed by Dr. Roger Tomilson of Canada in 1964, who is also known as ‘Father of
GIS’. To achieve G.I.S., Remote Sensing can be adequately thought of as a tool.

Remote sensing means obtaining information of an object, area or phenomenon without coming
in direct contact with it. The development of remote sensing over a time can be broadly divided
into the following six phases. Initial phase (upto 1920), Development of platforms and sensors
(1920-1945), Development of Teaching and Training (1945-1950), development of instruments
for interpretation (1950-60), Significant phase (1960-85) and Recent development phase (1985
onwards). There are two types of remote sensing instruments, Passive and Active. Passive
instruments detect natural energy that is reflected or emitted from the observed scene. Passive
instruments sense only radiation emitted by the object being viewed or reflected by the object
from a source other than the instrument. Reflected sunlight is the most common ex ternal source

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 80

 of radiation sensed by passive instruments. Scientists use a variety of passive remote sensors.
This system employs Radiometer, Imaging Radiometer, Spectrometer and Spectroradiometer.
On the other hand, Active instruments provide their own energy (electromagnetic radiation) to
illuminate the object or scene they observe. They send a pulse of energy from the sensor to the
object and then receive the radiation that is reflected or backscattered from that object. Scientists
use many different types of active remote sensors. This system employs Radar (Radio Detection
and Ranging), Scatterometer, Lidar (Light Detection and Ranging) and Laser Altimeter.

Figure: Basic Principle of G.I.S. and Remote Sensing.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 81

 Applications of G.I.S. & Remote Sensing in Environmental Engineering Practices

Remote sensing and G.I.S. is the only technique that can provide holistic approach to the study of
total environment. However, more advanced spatial and modeling techniques are required to
support the decisions of managers and policy maker.

Environmental Monitoring

It is important to monitor the quantity, health and diversity of the forests, and further related
aspects such as Deforestation (Rainforest, mangrove colonies), Species inventory, Watershed
protection, Coastal protection etc.

Geological Application

It is a fact that Geology helps in the study of landforms, structures and the subsurface. So as to
understand the various physical processes creating and modifying the earth’s crust.
Remote sensing is used as a tool to extract information regarding the land structure composition or
subsurface. In this arena, its applications encompass Surface deposit/bedrock mapping, lithological
mapping, structural mapping, sand and gravel exploration, mineral exploration, hydrocarbon
exploration, environmental geology, geo-botany, sediment mapping and monitoring, event
mapping and monitoring, geo-hazard mapping and planetary mapping.

Urban mapping applications

While majority of remote sensing work has been focused on natural environments over the past
decades, applying remote sensing to urban areas is relatively a newer application. Most urban
sensing technology is relatively driven by technology advances and societal needs. The
applications are as follows:

E-Hydrological Applications
Water Pollution Control
Soil Water and Drought Monitoring for early Warning Applications
Application of Remote Sensing in Coastal Ecosystem

NGO’s

The term, "non-governmental organization" or NGO, came into currency in 1945

because of the need for the UN to differentiate in its Charter between participation
rights for intergovernmental specialized agencies and those for international private
organizations. They only have to be independent from government control, not
seeking to challenge governments either as a political party or by a narrow focus
on human rights, non-profit-making and non-criminal.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 82

 The structures of NGOs vary considerably. They can be global hierarchies, with either a relatively
strong central authority or a more loose federal arrangement. With the improvement in
communications, more locally-based groups, referred to as grass-roots organizations or community
based organizations, have become active at the national or even the global level.

At times NGOs are contrasted with social movements. Much as proponents of social movements
may wish to see movements as being more progressive and more dynamic than NGOs, this is a
false dichotomy. NGOs are components of social movements.

Operational NGOs have to mobilize resources, in the form of financial donations, materials or
volunteer labor, in order to sustain their projects and programs. This process may require quite
complex organization. Charity shops, staffed by volunteers, in premises provided at nominal rents
and selling donated goods, end up providing finance to the national headquarters.

Fund-raising is still necessary, but on a smaller scale and it can serve the symbolic function of
strengthening the donors' identification with the cause. Persuading people to donate their time is
necessary, but, in addition to a small number of people giving a great deal of time, it is also necessary
to be able to mobilize large numbers for brief periods. External donors may not impose onerous
administrative burdens, but supporters still have to be supplied with information on an efficient
regular basis.

Narmada Bachao Andolan, Chipko movement, Green Peace, WWF are few acclaimed NGO’s.

ENVIRONMENTAL IMPACT ASSESSMENT

[E.I.A.]
EIA is a tool used for decision-making regarding developmental projects and programs and it may
be defined as a formal process used to predict the environmental consequences of any
developmental project.

EIA thus ensures that the potential problems are foreseen and addressed at an early stage in the
project planning and design.
EIA is intended to identify the environmental, social and economic impacts of a proposed
development prior to decision-making.

Objectives
Identify, predict, and evaluate potential environmental, social, economic impacts.
Best practicable environmental options
Utilise alternative strategies

To analyze adverse effects due to all project activities on the total environment in a systematic
manner

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 83

 To modify the project activities or to implement waste management programs to minimize
pollution levels before disposal

To select best alternatives with minimum adverse effects

Resource conservation/waste minimization/recovery of by products

Benefits:

Reduced cost and time of project implementation

Cost saving modifications in project design
Increased project acceptance
Avoiding impacts and violations of laws and regulations
Avoiding impacts and violations of laws and regulations
Improved project performance
Avoiding waste treatment/cleanup expenses
Deceased resource use
Maintenance of biodiversity
Fewer conflicts over natural resource
Increased community skills.
Improved human health

EIA process can be CEIA [COMPREHENSIVE] and/or REIA [RAPID].

The 2 distinct stages in EIA are

[1 ] Preliminary Assessment (carried out in the early stages of planning)

[2 ] Detailed assessment (carried out during project planning until the project plan is completed
and is reported formally as an environmental impact statement.

Public hearing is a key facet of any EIA project depending on its magnitude where in area
inhabitants to be impacted are informed of the developmental process in presence of Govt a nd
Project Employees.

The key elements are:

SCOPING - identifying key issues and concerns of interested parties

SCREENING – deciding whether an EIA is required based on information collected.
Identifying and evaluating ALTERNATIVES: listing alternative sites and techniques and the
impact of each.
MITIGATION measures – dealing with uncertainty; reviewing proposed action to prevent or
minimize the potential adverse effects of the project.
Issuing environmental STATEMENTs; reporting the finding of EIA.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 84

 ENVIRONMENTAL MANAGEMENT SYSTEMS
[E.M.S.]

An Environmental Management System (“EMS”) is a tool that is continuously growing in

importance for companies. Most companies need to manage their products/services, employee
safety, public opinion, environmental impact and other related opportunities. An EMS
encompasses the methods and means to manage all of these aspects within your organization and
helps you run and document its programs for environment-related management. If you want to
become certified to ISO 14001:2015 we offer an all-in one certification package.

This can and does include comprehensive and systematic planning and commitment of key
resources for developing, implementing and maintaining procedures for the preservation of the
environmental systems of the planet. Basically, an EMS allows an organization to continuously
monitor and improve all of their processes and impacts as it relates to the environmental system
that they have created as part of their ongoing operations.

ISO 14001:2015 specifies the requirements for an environmental management system that an
organization can use to enhance its environmental performance. ISO 14001:2015 is intended for
use by an organization seeking to manage its environmental responsibilities in a systematic manner
that contributes to the environmental pillar of sustainability.

ISO 14001:2015 helps an organization achieve the intended outcomes of its environmental
management system, which provide value for the environment, the organization itself and
interested parties. Consistent with the organization's environmental policy, the intended outcomes
of an environmental management system include:

· enhancement of environmental performance;

· fulfilment of compliance obligations;

· achievement of environmental objectives.

ISO 14001:2015 is applicable to any organization, regardless of size, type and nature, and applies
to the environmental aspects of its activities, products and services that the organization determines
it can either control or influence considering a life cycle perspective. ISO 14001:2015 does not state
specific environmental performance criteria.

ISO 14001:2015 can be used in whole or in part to systematically improve environmental

management. Claims of conformity to ISO 14001:2015, however, are not acceptable unless all its
requirements are incorporated into an organization's environmental management system and
fulfilled without exclusion.

KLS VDIT, Haliyal Department of Civil Engineering Prof. Rakesh P 85