ENVIRONMENTAL IMPACT
ASSESSMENT
Introduction
Environmental Impact Assessment (EIA) is a process of evaluating the
likely environmental impacts of a proposed project or development,
taking into account inter-related socio-economic, cultural and human-
health impacts, both beneficial and adverse
Project includes:
Thermal power project
Airport project
Industrial project
Dam and Irrigation project
Hydroelectric power plant
Highways and bridges
UNEP (United Nations Environmental Program) defines Environmental
Impact Assessment (EIA) as a tool used to identify the environmental, social
and economic impacts of a project prior to decision-making. It aims to predict
environmental impacts at an early stage in project planning and design, find
ways and means to reduce adverse impacts
Impact:
A change or deviation of the baseline situation arising from a proposed
plan/project
Baseline situation :
It is a existing environmental condition before a project/activity
History of EIA
It was first developed in US as a result of national environmental policy
act in 1969
History of EIA in India
It started in 1976-77 when the Planning Commission asked the Department
of Science and Technology to examine the river-valley projects from an
environmental angle.
The Ministry of Environment, Forests and Climate Change (MoEFCC)
notified new EIA legislation in September 2006
AIMS of EIA
1. Evaluation PRIOR to decision making
2. Planning for MITIGATION ( reduction of adverse affects) measures
3. To support the GOALS of environmental protection and sustainable
development
4. To provide ADVICE to the decision makers whether to proceed or not
Importance of EIA
EIA provides a cost effective method to eliminate or minimize the adverse
impact of developmental projects.
EIA enables the decision makers to analyze the effect of developmental
activities on the environment well before the developmental project is
implemented.
EIA encourages the adaptation of mitigation strategies in the developmental
plan.
EIA makes sure that the developmental plan is environmentally sound and
within the limits of ecosystem
Factors affecting EIA
Meteorology and air quality – related to Atmosphere
Topography – related to shape & features of area
Water – related to hydrological
Demographics – related to population
Land use – related to use of land
Soil condition – related to properties of soil
Mineral resources
Ecological study – related to flora & fauna
Classification of environmental parameters
1. Physical resources
- Soil erosion
- Soil fertility
- Loss of rain water infiltration
- Micro effects on increasing temperature
2. Ecological resources
-Loss of forest resources
-hazards from pesticides
3. Human/economic resources
- Impairment ( state of being weakened/damaged)
4. Quantity of life values
-Loss of forest/tourism
-Increased sanitation due to increased population
The EIA Flow Chart
The EIA Process/Elements of EIA
1. Screening:
Usually done by EIA authority or govt. agencies constituting a variety of
experts as a multi disciplinary team
2. Scoping:
Recognizes important issues of concern at preliminary level of the planning
process
It helps in site selection and possible technical options
It provides sufficient information to the public about the proposed project
3. Assessment and alternatives
Positive and negative, temporary and permanent impacts, alternatives for
site selection, techniques need to be predicted by EIA authority
4. Public hearing:
Public and environmental groups living close to project site may be
informed and consulted
5. Mitigation measures and EIA report:
The EIA report should include the actions and steps for preventing,
minimizing or by passing the impacts or else the level of compensation for
probable environmental damage or loss
6. Decision making:
Impact Assessment Authority along with the experts consult the project-in-
charge along with consultant to take the final decision, keeping in mind
EIA and EMP (Environment Management Plan)
7. Monitoring and implementation of environmental management plan:
The various phases of implementation of the project are monitored
LCA-Life Cycle Analysis
It is a tool to evaluate the environmental effects of a product or
process throughout its entire life
It includes identifying and quantifying the energy and material used
and waste released into environment and accessing their
environmental impacts
It helps to design the new products that are ecologic friendly
Example: Fruit juices are packed in 2 alternatives
Glass bottle or carton
Carton is environmentally best choice for packing
Stages of LCA
1. Goal and scope definition:
The aims of the study are defined, namely the
intended application, the reasons for carrying out
the study and the intended audience
2. Life Cycle Inventory (LCI) analysis
It involves the data collection and the quantification
of inputs and outputs of the study.
Inputs and outputs concern energy, raw material
and other physical inputs, products and co-products
and waste, emissions to air/water/soil, and other
environmental aspects
3. Life Cycle Impact Assessment (LCIA)
It involves assessment of impacts on resource depletion on human health and
ecological impacts
This is done through LCIA methods which firstly classify emissions into
impact categories and secondly characterize them to common units so as to
allow comparison
4. Life Cycle Interpretation phase
Results from LCI and LCIA are interpreted in accordance to the stated goal
and scope by the decision makers to reduce the impact of the products on the
environment.
This step includes completeness, sensitivity and consistency checks
LCA steps
Inputs & Outputs over product’s life cycle
EIA
METHODOLOGIES
Criteria for selection of EIA Methods
1. Simplicity
The methodology should be simple so that the available manpower with
limited background knowledge can grasp and adopt it without much
difficulty
2. Manpower time and budget constraints
The methodology should be applied by a small group with a limited budget
and under time constraints
3. Flexibility
The methodology should be flexible enough to allow for necessary
modifications and changes through the course of the study
Major Methodologies for EIA
The methodologies can be broadly divided into five types on
the basis of impact identification strength.
1. Ad hoc methods
2. Matrices methods
3. Network methods
4. Overlays methods
5. Cost/benefit analysis
1. Ad hoc methods
Ad hoc methods indicate broad areas of possible impacts by listing composite
environmental parameters (Ex: flora and fauna) likely to be affected by the
proposed activity
This method serves as a preliminary assessment and helps in identification of
important areas like:
1. Wildlife 9. Noise
2. Endangered species 10. Air quality
3. Natural vegetation 11. Visual description and services
4. Exotic vegetation 12. Open space
5. Grazing 13. Recreation
6. Social characteristics 14. Health and safety
7. Natural drainage 15. Economic values
8. Groundwater 16. Public facilities
Advantages:
This method is very simple and can be performed without any training.
It does not involve any relative weighting or any cause-effect
relationship.
It provides minimal guidance for impact analysis while suggesting broad
areas for possible impacts
Dis-advantages
It gives no assurance that a comprehensive set of all relevant impacts have
been studied.
Analysis using this method lacks consistency as it different criteria are
selectively evaluated by different groups
2. Matrices Method
This methodology provides a framework of interaction of different activities of a
project with potential environmental impacts caused by them.
A simple interaction matrix is formed when project actions are listed on one axis
(usually vertical) and environmental impacts are listed along the other axis
Advantages:
The matrix method is that it links action to impact
This is a very good method for displaying EIA result.
Disadvantages:
It is difficult to distinguish between direct and indirect impacts using this
method.
There is potential for double-counting of impacts.
It is qualitative in nature and does not refer to quantity of impact
3. Network Method
This method uses the matrix approach and extends it to include both the
primary as well as the secondary impacts.
It is shown in the form of a tree called impact tree.
Identification of direct, indirect along with short, long term impact is a crucial
and basic step of making an impact tree.
The impact tree is used to identify cause-effect linkages
Advantages:
It links action to impact.
It is useful to check second order impacts in a simplified form.
It handles direct and indirect impacts.
Disadvantages:
It becomes overly complex if used beyond simplified version.
It is completely qualitative in nature
4. Overlays Method
Overlay methods involve preparation of a set of transparent maps, which
represent the spatial distribution of environmental characteristics (e.g.,
Extent of dense forest area).
These maps will be overlaid to produce a composite
The resulting composite maps characterize the area's physical, social,
ecological, land use and other relevant characteristics relative to the location
of the proposed development
Advantages:
It is easy to understand and use
It has a good display
It is good for setting site selection
5. Cost – Benefit Analysis (CBA)
Cost benefit analysis is a systematic process for identifying, valuing and comparing
costs and benefits of a project.
It is a systematic approach to estimate the strengths and weakness of alternatives
(for ex. In transactions, activities, functional business requirements or project
investments)
It is used to determine options that provide the best approach to achieve benefits
while preserving savings.
CBA is a standard tool for evaluating the economic analysis or trade of analysis,
investment of development projects.
THANK YOU
