5. EIA methodologies

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Mestrado em Engenharia do Ambiente"
Master on Environmental Engineering"
Impactes Ambientais / Environmental Impacts
5/9"
5
Metodologias e técnicas de AIA /
EIA Methodologies and techniques
"
"
Prof. Doutora Maria do Rosário Partidário
1
Content
1.  Significance of environmental impacts
2.  Methods and techniques
3.  Uncertainty in impacts prediction
4.  Current state of the environment
5.  Alternatives identification and comparison
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Bibliography!
CANTER, L. 1996, Environmental Impact
Assessment. McGraw-Hill. (ch 3, ch
15)"
Morris, P. and Therivel, R. (Eds), 2001.
Methods of Environmental Impact
Assessment, 2nd edition, Spon Press,
London (2008 reprint).
Partidário e Jesus, 2003. Fundamentos
de Avaliação do Impacte Ambiental.
Universidade Aberta. "
Significant impacts
Canadian guidance
•  Determine adverse negative impacts
•  Determine magnitude, including cumulative impacts
• Determine geographical extension of negative impacts
• Determine duration and frequency
•  Determine the degree of reversibility
•  Assess its probability of occurrence
•  Assess the scientific uncertainty of the probability of
occurrence of a significant impact
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Key elements to establish the
significance (importance) of an
impact
• 
• 
• 
• 
• 
• 
• 
Cultural Importance
Social Importance
Ecological Relevance
Environmental Patterns
Statistic significance
Technical issues
Political/institutional issues
Themes of interest in EIA
•  Public health
•  Safety and security, occupational
health
•  Vulnerable groups
•  Gender
•  Economic organization and wellbeing
•  Population growth
•  Cultural and aesthetic values
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Impact assessment – criteria for
significant impacts - USA (1/2)
•  health and safety
•  unique characteristics in a geographical area, such as historical
and cultural resources, wetlands, scenic rivers, critical areas for
nature conservation
•  human environmental quality at highly controversial levels
•  Unceratin, unique or unknown risks on the human environment
•  Precedent for future projects with significant impacts
Impact assessment – criteria for
significant impacts - USA (2/2)
• Cumulative impacts
•  destruction of designated buildings, places or objects (cultural
and historical) or scientific resources
•  species or designated habitats
•  Risk of violation of any law or regulation for environmental
protection
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Finding the significance of impacts
All the possible effects of proposed project
Environmental filter
Significant impacts
Impact analysis
 Decision factors
 Environmental
relevance
Scaling impacts
Methods and techniques in EIA
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EIA methodologies
Introduction!
1/3
EIA methodologies – approaches developed to
identify, predict and value changes of an
action.
Reflected in the sequence of activities, steps, as
well on the range of environmental issues
considered (physical, chemical, biological,
socioeconomic, cutlural, landscape values and
processes)
EIA methodologies
Introduction!
2/3
•  Uses methods and techniques to quantify or
to qualify those changes. All aspects and
variables can be measured, problem is to
value them.
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EIA methodologies
Introduction!
3/3
The development of METHODOLOGIES to assess
impacts depend on:!
a)  The relationships between territorial elements (or
characteristics) and the actions
b)  The specific measurements and the necessary
information to estimate the impacts
c)  The mitigation measures, compensation and
follow-up
Objectives of methodologies!
1.  Understand the nature and location of the project and
possible alternatives"
2.  Identify factors of analysis and assessment objectives"
3.  Preliminary identification of impacts and scoping"
4. Baseline studies and evolution in the absence of projects"
5. Prediction and assessment of impacts and alternatives
comparison"
6. Mitigation"
7. Monitoring and impacts management"
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Example of methods!
1.  Experts judgement
2.  Checklists and matrices
3.  Flowcharts and decision trees
4.  Multicriteria analysis
5.  Case comparison
6.  Simulation Models
7.  GIS and map overlays
8.  Contingency analysis
9.  CBA, CEA, other economic evaluation
Checklist
•  Structured list of environmental factors potentially affected."
•  Extensive and complete. Main function: identify ALL possible
consequences of the proposal"
•  Should enable identification of impacts on:
  Soil
  Water
  Atmosphere
  Flora
  Fauna
  Resources
  Recreation
  Cultural
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Checklists
Three types:
1.  Simple : no information needed on magnitude or importance of
impacts"
2.  Descriptive, require information on magnitude or importance of
impacts as well as indication on prediction methods and
indicators."
3.  Questionnaires, three types of answer: yes , no , may be "
Simple checklists
Impactes
Project phase
Design
1. On water
1.1. Poluição
1.2. Decréscimo do caudal
1.3. Cambio de uso
Construction
Abandonnement
X
X
X
2. On air
2.1. Poluição
2.2. Incremento do ruído
2.3. Presencia de maus cheiros
X
X
X
3. On climate
3.1. Cambio de temperatura
3.2. Aumento das chuvas
3.3. Aumento da evaporação
3.4. Aumento de nebulosidade
X
X
X
X
4. On soil
4.1. Perda de solo
4.2. Dunas
4.3. Acidificação
4.4. Salinizaçao
4.5. Geração de pântanos
4.6. Problemas de drenagem
X
X
X
X
X
5. On vegetation and fauna
5.1. Perda de biodiversidade
5.2. Extinção de espécies
5.3. Alteração sobre espécies endémicas
5.4. Alteração sobre espécies protegidas
X
X
X
X
6. On population
6.1. Perda de base de recursos
6.2. Alterações culturais
6.3. Perdas de recursos arqueológicos
6.4. Traslado de população
X
X
7. Other
7.1. Perda de valores paisagísticos
Operation
X
X
X
X
X
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•
Increase existing noise levels?
Yes
May be No Observation
!
!
!
!
!
!
!
!
!
Vegetation. Will the project:
•
Change the diversity or productivity of
species or the number of any species
(including trees, shrubs, aquatic plants,
etc.)?
Energy. Will the project:
•
Use substantial amounts of energy?
Transports and traffic. Will the project:
•
Generate additional traffic?
!
!
!
•
Have effects or increase demand on
parking infrastructures?
!
!
!
!
!
!
Public services Will the project have effects on, or
result in, need for new services or changes in the
following areas:
•
Fire services?
•
.....
Public reaction. Is the project:
•
Potentially controverse?
!
!
!
•
Conflictual
with
objectives
in
environmental plans locally adopted?
!
!
!
Checklists: impact identification
Issue
Noise. Will the project:
EIA process and activities.
EIA applications (sessions 5 and 6)
Checklists: environmental sources
Key criteria
Air and climate
changes
Protected areas
Natural
resources
Water
Soil
Landscape
Noise
Coastal areas
Key Environmental sources
! Air quality levels;
! Sulfur dioxide levels;
! CO2 emmission
! Designated areas (ha) under national or international protection (for example
Natura 2000 – Special Conservation Areas and Special protection Areas
....
....
....
....
....
....
INTERNATIONAL MASTER IN SUSTAINABLE DEVELOPMENT AND CORPORATE
RESPONSIBILITY / Professor Maria do Rosário Partidário
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Checklists
Advantage
• 
structured list of key potential factors for analysis or key impacts - aidememoire;
• 
often result from experts judgement published by public / international
organizations;
• 
enable interdisciplinary discussions;
• 
preparatory stage for matrix assessment (checklist of actions /activities and
checklist of environmental components);
Disadvantage
• 
Guided tour - standard analysis, misses specific issues
Matrices!
Double entrance tables, permit establishment of
relationships: "
1.  Project actions or activities (causes) "
2.  And the environmental factors (effects)"
"
Functions:"
"
- Preliminary identification of impacts (scoping)"
- Comparative analysis of alternatives"
- Impact assessment"
-Presentation of evaluation results"
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Matrices!
a
a
2
b
1
b
c
d
e
+8
5
7
8
1
9
2
8
3
7
Leopold Matrix (Leopold et al., 1971). 100 causes per 100
effects.
Magnitude (left-hand corner) and Importance or significance
(right-hand corner). Scale 1 to 10. Values can still be
signaled as positive ( “+”) or negative (“-”).
Matrices – Basic rules
"
1.  Objectives and assumptions clear."
2.  Matrices can be used creatively to identify indirect
impacts, cumulative impacts or contributions to
mitigation measures."
3.  Its better to use colour codes and graphical symbols in
matrices."
4.  The development ofa matrix does not imply that it
needs to be used in the report, it may simply be an
element of work "
5.  Each impact analysis needs to be contextualized."
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FLOWCHARTS!
Flowcharts and impacts trees, including network diagrams,
enable the analysis of the inter-relationship between
causes and effects and enables de analysis of indirect and
cumulative impacts. "
"
"
FLOWCHARTS!
Strong decrease of farms number
Land abandonment
D4: End of direct
payments
Incomes maintained for some farms thanks to
the development of labels and niche products
integrated in industrial ranges
D5: Roquefort and Féta
separated ; Méjan
specialised in Féta :
industrialists set
volumes and rules
D6: End of local
measures to pine control
Strategies of farms: to maximise
profitability
Shrub
encroachment,
extension of pine
forest: fast
landscape closure
and cultivated
land turned in
fallows
Extension of pine
forest: fast
landscape closure
Strong increase of
forest areas & strong
fire risks
Decrease of
cultivated areas
Local agriculture with
high value products
Tourism
Intensive ovine
breeding
Strong decrease of
rangelands and
grasslands & strong
erosion of biodiversity
Intensification of
cultivated areas
Arable lands
concentrated on high
potential lands
Increase of wild
ungulate
populations
Hunting
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Fluxograma de impactes da aplicação aérea de herbicida
(Bisset, 1983)
Aplicação aérea
de herbicidas
Contaminação
da água por
herbicidas
Decréscimo do
crescimento de
algas,
fitoplancton, etc
Contaminação
de cadeia
alimentar no
meio aquático
Perda de
vegetação
ripícola
Mortalidade de
vegetação para alem
da pretendida com o
herbicida
Decréscimo do
oxigénio
dissolvido
Aumento da
temperatura da
água
Aumento do
escoamento
superficial
Contaminação de
cadeia alimentar
no meio terrestre
Danos na
desova
Poluição da água
por sólidos
flutuantes
Aumento da
erosão
Aumento da
carência de
oxigénio
dissolvido
Aumento dos
sedimentos
Aumento do
caudal
Aumento da
perda de água
Flowcharts / Networks
Advantages:
- integrated assessment, instead of discipline by
discipline
-  inter-relations between causes and effects, including
indirect impacts
-  cumulative impact assessment
-  communication (when simple).
Disadvantages:
- complexity (especially visually complex)
- difficult to distinguish and quantify magnitudes (and
importance) of different impacts
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Mapping spatial areas
Overlays and GISs
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Overlays and GISs
Cartográfica
IMPACTE 1
Área de análise
Lavado de suelos
IMPACTE 3
Ruidos
IMPACTE 2
Modificación de hábitats
IMPACTE 4
Alteración cobertura vegetal
IMPACTES ACUMULADOS
Área de influencia
Arcview
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Definition of areas of maximum infiltration
IFI= valorTHS+valorT+valorAGUT Fonte: Luis Ribeiro, PU Carregueira, 2009
Sinopse dos Métodos de avaliação de
impactes vs. etapas do AIA
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There is no single ideal
method!
Uncertainty in impacts
prediction
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Sources of uncertainty:
•  information on baseline and on the project
(quantity, precision, reliability)
•  associated to the model
•  preparation of the model
•  application of the model
Uncertainties related to:
quantity: spatial and temporal resolution, reading
mistakes, bias and imprecisions associated to the
technique.
precision: detail on measurements
reliability: correctin of such measurements
The more precise is the information the more
difficult it is to get reliable data.
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Baseline characterization
Baseline
Characterization should:
"
•  limit itself to the relevant affected factors"
"
• be proportional to the probable significant impact"
"
1st step- establish objectives in information collection"
"
Do not collect and present available information just because it is
available, if it is irrelevant, concentrate efforst on relevant
information"
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2nd step- analysis of available information and verification of such
information to the defined objectives."
variável ambiental
- spatial and temporal representativeness"
t1
t2
tempo
3rd stage- identify additional information needs, field work/ time
available"
4th stage- synthesize collected information and identify gaps in
knowledge and how important they are to the keyobjectives"
"
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Baseline - methods
•  Methods vary depending on natural, social or economic
variables"
•  Function of scoping and impacts identification"
Criteria for selection of methods:"
"
-  Objectives"
-  impact indicators (relationship with monitoring)"
-  limitation: time and budget"
Prediciton of impacts - Methods
Prediction of impacts is based on the quantification
or descriptive qualification of impacts identified.
Prediction impacts are clearly dependent on impacts
and disciplines.
Type of methods:
• Experts opinion
• Case comparison
• Use of models
• Experiments
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Prediciton of impacts - Models
Physical models – representation of the reality ina reduced scale,
simulating processes. (Exs. Wind tunnels or coastal area physical
models that simulate waves)
Visual models – elaboration of images that represent the
environment before and after the development of a project and its
alternatives. It can also address the timing dimension (e.g., seasonal
changes, vegetation growth).
Mathematic models- maths or statistic simulations applied to the
deterministic or probabilistic calculation, based on quantitative values.
Cartographic models- representation of reality that will be affected
by the project through maps or charts. Cartographic overlaps enable
impact preditions.
Impact Assessment
Meaning (or importance) of an impact depends on its scale
(geographic scale and duration) and its intensity.
Impacts can be positive or negative. Significative negative
impacts may occur even when the global balance of
impacts is positive.
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Alternatives comparative
assessment
The object of analysis in alternatives assessment is to
define the merits and disadvantages of realistic
alternatives, enabling to decision-makers and to the
public a clear basis for the choice of option (World
Bank, 1996)
Technical, economic, social and environmental viability
of alternatives: the proponent needs to be willing to
develop any of the alternatives being considered
Alternatives comparative
assessment
Analyse separately the sets of alternatives, whenver
possible.
A
1
B
2
3
4
C
5
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Alternatives comparative assessment
In relation to decision factors
• Define the alternatives to be analysed
• Define the factors of analysis (decision factors)
• Weighting the decision factor
Decision factors
A1
Alternatives
A2
A3
A4
A5
F1
F2
F3
F4
Methods for alternatives comparative
"
assessment
Multi-criteria assessment"
1.  Quantitative and qualitative assessment"
2.  Weighting the decision factors"
Methods: "
Process of nominal group (group intercative technique)"
1) Nominal generation of ideas (silent and independent) "
2) Table checklist"
3) Group discussion (clarification, evaluation) (e.g. Delphi method)"
4) Order voting or assessment in a numerical scale "
Delphi method"
Preparation of an individual questionnaire per panel member.
Communication of results to each panel member and new round of
voting."
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Preparation of the following table for experts selection and
assessment"
Factor (ou área de
impact e )
Reduzida
importância
1
2
3
Elevada
importância
4
5
Total
Peso
F1
F2
F3
F4
F5
….
1.  Each experts fills in the table based on comparison of factors "
2.  Calculation of total"
3.  Weight results from the division of each factor by the total "
4.  Calculate the average of the tables as filled in by each expert"
5.  Each expert compares the average of the group with its own value"
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