The document summarizes the key steps in performing an environmental risk assessment (ERA) as part of an environmental impact assessment (EIA). It discusses the five main steps: 1) hazard identification, 2) hazard analysis and scoping, 3) exposure assessment, 4) risk characterization, and 5) risk management. For each step, it provides details on the objectives and processes involved. It also compares EIA and ERA, noting that ERA focuses specifically on identifying and analyzing potential environmental hazards and risks, which helps to inform the overall EIA process.

1. UNIT - 5
ASSESSMENT OF IMPACTS OF DEVELOPMENTAL ACTIVITIES ON VEGETATION
AND WILDLIFE
By -
G.kalyan

2. ASSESSMENT OF IMPACTS OF DEVELOPMENTAL ACTIVITIES ON
VEGETATION AND WILDLIFE:
The impacts of vegetation and wildlife will be most likely intense in rural areas and for proposed projects or actions
covering large geographic areas or setting future management policies.
In urban areas, however, small tracts of natural vegetation and habitat may be extremely important if there is an
absence of similar habitat in the area or region.
Wetlands are a significant habitat for numerous species of plants and animals. Vegetation and wildlife studies often
focus on threatened or endangered species.
The environmental analyst should assess the possible project or action effects on vegetative ecosystems and
wildlife species that are protected by law. Game species and other unprotected species and the systematic approach
for this involve mostly,
(a) assigning the existing biological resumes,
(b) impacts analysis of project activities, and
(c) mitigation.

3. Impact Analysis
The level of detail required for impact analysis for vegetation and wildlife will depend on the specific characteristics of
the proposed project alternatives and the expected degree of effects. Examples of the types of impacts that may be
applicable are loss of unique vegetative communities, direct loss of wildlife habitat and species, deterioration of
remaining habitat, barriers to wildlife travel corridors, and effects on recreational activities and land use.
Loss of Valuable Vegetative Community Types
The analysis of degree of impact of direct loss of vegetation will depend heavily on the value of the vegetative
community to be destroyed. If the vegetation is common and unremarkable, the effects can be quantified by the amount
of each type of community to be destroyed for each proposed alternative.
Mitigation
Mitigation for potential impacts on vegetation and wild life may be very site-specific, such as, replacing landscaping or
creating open space and parks in more urban areas; or geographically expansive in scope, such as, implementing
particular management techniques in national forests. In some cases, rare plants or particular animals may actually be
transplanted or trapped and moved to other safe locations.
Mitigation measures include
1. Avoiding
2. Minimizing
3. rectifying
4. reducing and
5. compensating.

4. Deforestation
Deforestation means cutting down the trees to a large extent be it forests, any barren land or trees we see on our way
to school every day. Natural forests are being destructed to use the land for cultivation, building houses, factories,
logging, making space for cattle grazing, extraction of oil, mining, and construction of dams or to obtain wood for
making furniture and using it as fuel.
Causes of Deforestation
Logging :
Illegal logging activities are very common that destroy the livelihoods of the people depending on forests. Wood-
based industries like paper, match-sticks, furniture need a substantial amount of wood supply. Wood is used as fuel
most commonly and so large amount of trees are cut down for fuel supplies. Firewood and charcoal are used as fuel.
Agricultural Activities :
The conversion of forests into agricultural land is a big reason for deforestation. Due to overgrowing demand for food
products, many trees are chopped down for crops and for cattle grazing. Over 40% of the forests are cleaned to obtain
land and meet the needs of agriculture and wood.

5. Mining:
Oil and mining of coal require a large amount of forest land. Construction of roads leads to deforestation as they
provide the way to remote land. The waste that comes out from mining pollutes the environment and affects the
nearby species.
Urbanization :
As the population grows, the needs of people increases which further leads to deforestation. Forests shrink to a great
extent to meet the requirements like for construction of roads, development of houses, mineral exploitation and
expansion of industries. Increasing population directly affects forest as with the expansion of cities there is a need
for more land for housing and settlements.
Timber Production :
One of the primary cause of deforestation is the production of timber. There is a lot of demand for timber and so
deforestation increases. It a source of raw material which is used for the production of paper and also for
construction.
Forest Fires :
We lose a large number of trees each year due to fires in the forest in various portions worldwide. This happens due
to extreme summers and winters. The fire caused, by man or nature, results in huge loss of forest cover.

6. Effects of Deforestation:
Some of the effects of deforestation are:
Greenhouse Gas Emissions
Gases such as methane and carbon dioxide trap heat in Earth’s atmosphere, leading change in climate. Trees absorb the
carbon dioxide and release oxygen and water into the atmosphere and this contributes to global warming. Cutting carbon
dioxide adds to the environment and then this lack of the tree creates an absorption deficit. Deforestation leads to the
emission of greenhouse gas.
Soil Erosion
Cutting down on trees leads to clearance of forests and so soil erosion occurs. Exposure of the soil to the sun’s heat dries
up the moisture inside the soil. Nutrients evaporate and it affects the bacteria that help to break down organic matter. Due
to this, rain washes the soil surfaces and erosion takes place. Large amounts of soil wash into local streams and rivers and
cause damage to hydroelectric structures and irrigation infrastructure.
Biodiversity Losses
Deforestation alters land and so that many of the plants and animals do not survive. With more deforestation, the entire
species can extinct. This is the ‘biodiversity loss’. Many wonderful species of plants and animals have been lost, and
many others remain endangered. As each species of an ecosystem rely upon other species, loss of one species can have
far-reaching consequences for other species. We lose about 50 to 100 species of animals each day .

7. Floods
Deforestation leads to land erosion because the trees maintain the surface of the mountains. The water level of the rivers
increases suddenly, causing floods. When it rains, trees absorb and store a large amount of water with the help of their
roots. Chopping down of trees disrupts the flow of water and leads to floods in some areas.
Solutions to Deforestation
Trees play a vital role in protecting our environment in several ways so we should protect the forest:
● The best way to stop deforestation is replanting.
● Ban on cutting of trees and new trees and planting more.
● There should be an implementation of regulations of laws at organizational and governmental levels due to the
extent of deforestation.
● Spread the awareness about sensitization and organize educative campaigns about the effects of deforestation.

8. Environment Risk assessment and Risk management in EIA:
● According to International standard ,risk is defined as the chance of something happening,that will
have impact on objectives.
● According to Environment protection act,risk is the chance of harmful effects to human health or to
ecological systems resulting from exposure to an environmental stressor.
● In general risk can be defined as anything that has a tendency to cause harm to humans and the natural
environment medium (including air,water,land,plants and wild life).
● Risk management is defined as the culture processes and structures that are directed towards realizing
potential oppurtunities whilst managing adverse effects.

9. Some of the Terms used in Risk Assessment as given below :
Hazard:
a property or a situation with the potential to cause harm
Risk:
a combination of the probability or frequency of the occurrence of a particular
hazard and the magnitude of the adverse effects or harm arising to the quality of human health or the
environment.
Probability :
the occurrence of a paIticular event in a given period of time or as one amongst a
number of possible events
Risk Managemellt :
the process of implementing decisions about accepting or altering Risks

10. Risk Assessment and treatment of uncertainity:
Environmental risk assessment has an important role in managing the uncertainity as part of an
EIA process.
Theuncertainity in risk assessments arise due to lack of knowledge regarding a particular
parameter.
It arises from two sources.
1)Randomness:
This is due to the varying phenomena or because all factors affecting a system
cannot be modelled.
2)Incompleteness:
This is due to lack of information about parameter values

11. Key Steps in Performing an Environmental Risk Assessment (ERA) :
The five step sequence in performing ERA is:
1. hazard identification - sources of adverse impacts;
2. hazard accounting - scoping, setting the boundaries of the
ERA;
3. scenarios of exposure - how the hazard might be
encountered;
4. risk characterization - likelihood and severity of impact
damage; and
5. risk management - mitigation or reduction of unacceptable
risk

12. Step 1 - Hazard Identification
This is, in fact, a preliminary risk assessment, immediately useful to managers in appraising the project or activity
upon which they are embarking. Hazardous chemicals are a major topic for ERA. Elaborate screening procedures
have been devised to judge when a chemical merits full investigation.
Step 2 - Hazard Analysis
Risk managers must state their concerns alld indicate possible linkages of operations to
mitigation measures. Some of the scoping choices to be made are:
• geographic boundaries;
• time scale of impacts;
• stages of the causal chain of events;
• phase or phases of the technological activity;
• whether to include routine releases or just accidents;
• whether to include workers or just the general population:
• definitive end points for health or ecosystem effects; and
• cumulative effects and interactive risks that result from other projects

13. Step 3 – Exposure Assessment
This stage of ERA is used to know the hazard might be encounterd

14. Step 4 - Risk Characterization
Risk characterization facilitates the judgment of risk acceptability. Risks to health are
typically characterized in terms of:
• exposure period;
• potency of a toxic material;
• number of persons involved;
• quality of models;
• quality of data, assumptions, and alternatives;
• the uncertainties and confidence in the assessment; and
• appropriate comparisons with other risks.
• useful risk characterization expressions include:

15. • probability of the frequency of events causing some specified number of prompt
fatalities (for example, equipment failure releasing toxic gas that kills ten or more
people is estimated to occur every fifty years);
• annual additional risk of death for an individual in a specified population (for
example,one in a million);
• number of excess deaths per million people from a lifetime exposure (for example,
250 people in the exposed population);
• annual number of excess deaths in a specific population (for example, living within a
certain distance from a hazard); and
• reduction in life expectancy due to chronic exposure, or chance of an accident

16. Step 5 - Risk Management
Risk - Cost - Benefit
The effectiveness a.,d efficiency of risk management depend on deploying limited resources where they are most
needed. Comparing risks and the costs of their reduction is a valuable decision tool. For example, hazardous waste
sites are perceived by many citizens as posing a high health risk, and large expenditures are made to clean them up.
Yet, when quantitative probabilistic risk assessment is performed on these sites they usually turn out to be relatively
low threats. This is because, in most cases, the chance of exposure is slightly due to isolation from drinking water
supplies and prevention of access. In contrast, the risk from indoor air pollutants is found to be relatively high and
worthy of greater reduction efforts than the public might demand. People spend most of their time indoors, often in
poorly ventilated areas, exposed to vapors of hazardous household products, to second hand tobacco smoke, and, in
some locations, to radon.

17. Comparison between EIA and ERA :

18. THE END
By - G.kalyan