تقييم الاثر البيئى لمشروعات الصرف الصناعى

Arab Republic of Egypt
Cabinet of Ministers
Egyptian Environmental Affairs Agency (EEAA)
Environmental Management Sector
Environmental Impact Assessment
GUIDELINES FOR MUNICIPAL
WASTE WATER TREATMENT WORKS
SEAM Project
Environmental Impact Assessment
GUIDELINES FOR MUNICIPAL
WASTE WATER TREATMENT WORKS
January 2005
Prepared by
SEAM Project
Egyptian Environmental Affairs Agency (EEAA)
Entec UK Ltd
SEAM Project
1 INTRODUCTION
This guideline identifies the main factors to be
considered when preparing an EIA for waste water
treatment works projects which discharge effluent
to non marine water courses. The principals for
EIAs for those works discharging to marine or
estuarine areas will be the same as those discharging
to freshwaters, but likely environmental impacts,
and consequently the baseline information required,
will differ considerably. They are, therefore, not
considered further in these guidelines.
Not all matters in these guidelines will be applicable
to every proposal, and this checklist is not
exhaustive. The EIA must be tailored to suit the
potential impacts of the specific proposal at the
specific proposed location(s), and it is essential to
focus on relevant key issues.
Use of this guideline alone will not be sufficient to
prepare an EIA. Reference should be made to
relevant laws and other guidelines, such as Law
4/1994 for the Environment, Law 48/1982
protecting the River Nile and its waterways from
pollution, Law 93/1962 concerning disposal of
wastewater to municipal sewers, relevant ministerial
decrees, EEAA Guidelines for Egyptian
Environmental Impact Assessment, and other
guidelines. Developers should be fully aware of
their obligations under all laws and guidelines
applicable to their situation.
The aim of Environmental Impact Assessment
(EIA) is to enable the approving authority, the
public, local and central government and the
developer to properly consider the potential
environmental consequences of a proposal, and to
make recommendations to reduce the
environmental consequences if necessary. It is
important to provide sufficient information for the
approving authority to make a decision on whether
to approve a proposal and if so, under what
conditions. The EIA provides the basis for sound
ongoing environmental management.
2 THE EIA PROCESS
The EIA process should proceed logically through
a number of steps. These steps work at two levels:
¨ technical work undertaken by specialist
contributors to the assessment;
¨ a guiding principle for the EIA overall,
providing a structure for the EIA report and coordinating
the technical contributions;
Each step in the EIA process requires consultation
to ensure that all relevant views are being taken into
account throughout the EIA process. Ideally
consultation should be maintained throughout the
EIA process with the developer and designer of the
proposed scheme, so that modifications to the
design to reduce potential environmental impacts
may be introduced before completion of the final
design. Consultation with the regulatory authorities,
and also with the public, should be initiated at the
Scoping stage of the EIA, and thereafter carried out
as appropriate. The steps in the EIA process are
broadly as follows, and are outlined in following
sections of this guideline.
2.1 Description of the project: What type of
project is it
2.2 Screening: is an EIA required
2.3 Scoping: What has to be covered and in
what detail
2.4 Baseline: What are the existing
environmental conditions
2.5 Prediction: What environmental effects will
the development have
2.6 Evaluation: How significant are the
predicted effects
2.7 Mitigation: Can significant negative effects
be avoided or made acceptable
The developer is ultimately responsible for ensuring
compliance with the statutory requirements for EIA
preparation. A developer may employ a firm of
consultants to carry out the assessment. The
developer should verify the competence of the firm
recruited to prepare the EIA.
The EIA should be prepared by a team with
expertise appropriate to the study of the different
aspects of the development site. The team should
be headed by a project manager, whose ultimate
responsibility is to co-ordinate the inputs of
individual specialists and to provide an overview.
For EIAs for waste water treatment works,
members of, or advisors to, the team should
include, but not necessarily be limited to, the
following:
¨ socio-economics specialist;
¨ health (water borne diseases) specialist;
¨ freshwater biologist, microbiologist or
biochemist;
¨ terrestrial/avian fauna and flora specialist;
¨ hydrologist/hydrogeologist;
¨ development planner or landscape architect;
¨ air quality (odour, dust and noise) specialist;
2 EIA Guidelines for Municipal Waste Water Treatment Works
SEAM Project
¨ transport/roads specialist;
¨ antiquities specialist;
¨ process engineer in wastewater treatment.
Some team members may fulfil several of the above
roles if suitably qualified and experienced.
Each member of the team, for their specialist
subject(s), will follow the basic processes identified
above: scoping, consultation, baseline data
collection, prediction and evaluation of impacts,
and identification of mitigation measures.
The following sections outline the basic steps in the
EIA process.
2.1 Outline of important characteristics
of the proposed project
Details of the proposed project will need to be
obtained in order to assess potential impacts of the
scheme. The basic minimum in order to complete
the following parts of the EIA process will need to
include:
¨ Proposed location of works;
¨ General layout;
¨ General unit process and description
diagram(s);
¨ Size in terms of population and population
equivalents, present and projected;
¨ Number and type of connected industries;
¨ Anticipated influent and effluent characteristics,
annual or monthly average discharge data;
¨ Pre-construction, construction, operation and
maintenance activities, estimated staffing, and
support facilities and services;
¨ Required off site investments;
¨ Life expectancy of major components.
2.2 Screening
This is the task of deciding whether or not an EIA
is required for a particular project. Basic details of
the proposed development will be needed for the
project to be screened. For waste water treatment
works the size of the population to be served by the
works is the critical information required to
determine whether an EIA is necessary.
Relevant legislation and guidelines (Law 4/1994 on
the Environment, EEAA Guidelines on Egyptian
Environmental Impact Assessment) identify
projects which must have an EIA, and those
projects where an EIA is discretionary or not
required. Reference to the Competent
Administrative may be necessary where the
requirement for an EIA is not clear. The EEAA
guidelines classify projects based on Law 4 into
three groups, reflecting severity of possible
environmental impacts:
¨ White list projects: those with minor
environmental impact. Wastewater treatment
plant of 1000 PE (population equivalent) or less
fall within this category. The developer applies
to the Competent Administrative Authority
before construction works are initiated, with a
letter of intent, accompanied by Environmental
Screening Form
is not required.
¨ Grey list projects: those which may result in
significant environmental impact. Wastewater
treatment plant with a capacity of 1000 to 1
million PE fall within this category. The
developer applies to the Competent
Administrative Authority before construction
works are initiated, with a letter of intent,
accompanied by Environmental Screening Form
of such projects may be required at the
discretion of the EEAA.
¨ Black list projects: those projects which require
complete EIA due to their potential impacts.
Wastewater treatment plant with a capacity of
more than 1 million PE fall within this category.
The developer applies to the Competent
Administrative Authority before construction
works are initiated, with a letter of intent,
accompanied by the scoped EIA. The EEAA
Guidelines include in Annex 1 sectoral
guidelines for establishments that need full EIA.
Further details regarding the procedures to be
followed can be found in the EEAA Guidelines.
In most cases, the Competent Administrative
Authority would be the Ministry of Housing, New
Communities and Public Utilities. This, however,
may vary according to the nature of the proposed
development.
2.3 Scoping
Scoping, or identification of potential
environmental impacts, is an important early stage
of the EIA process to ensure that the EIA is
properly carried out. For a project to be properly
scoped, a site visit and preliminary consultations
with relevant regulatory authorities must be
included (e.g. Ministry of Housing, New
Communities and Public Utilities, Governorate and
City/Town/Village authorities) at the scoping stage.
Ideally public consultation should also be carried
out the scoping stage, but it may be more suitable
EIA Guidelines for Municipal Waste Water Treatment Works 3
SEAM Project
to postpone consultation with the public until more
detailed assessment of potential impacts has been
completed. Consultations should involve exchange
of information about the characteristics of the
proposed project, and assistance to the consultant
in identifying regional and local issues and/or
sources of information of relevance to the EIA.
From consultations and a preliminary assessment of
baseline conditions the consultant must:
¨ identify the characteristics of the proposed
development that are likely to give rise to
impacts;
¨ identify what type of impacts may arise, and;
¨ determine which environmental resources and
people in the vicinity of the proposed site are
likely to be particularly sensitive to the above
impacts, and what categories of impacts are
likely to be a problem in this respect.
If either the project characteristics or the
boundaries of the proposed site should change,
then the potential impacts may also change, and the
scope of the EIA will need to be reviewed.
The EIA process will generally benefit from
focusing attention on the key issues of concern.
Not all issues identified will have the same degree
of relevance for all proposals.
The identification and prioritisation process should
result in:
¨ a list of all issues with a preliminary estimate of
the relative significance of their impacts;
¨ identification of the key issues;
¨ an explanation as to why other issues are not
considered to be key.
The EIA should address the key issues as fully as
practicable. However the level of analysis should
reflect the level of significance of the impacts and
their importance for the proposal. Lesser attention
should be given to those issues which have lesser
significance. For these latter issues, there should be
sufficient analysis to develop a sustainable
mitigation strategy for any potential adverse
impacts.
The consideration of alternatives, particularly
alternative sites or schemes, during the scoping
stage is often a good idea, as the amount of
information on alternatives is often very limited.
The scoping exercise can report why the preferred
alternative was chosen on environmental grounds.
The main part of the EIA can then concentrate on
the preferred option. Alternative processes within
the scheme may be dealt with as mitigation.
2.4 Baseline Environmental Conditions
Collating existing data is always the first step in
collection of baseline information. It can then be
reviewed for its relevance to the proposed site, its
currency, and used as a basis for determining what
survey work may be ne
Original site surveys are almost always bound to be
required for most categories of effect, such as air
quality, odours and noise; socio-economic situation;
water quality and aquatic biology; terrestrial ecology;
landscape. Published information usually does not
exist at a suitable scale, or is not generally applicable to
the development in question. Original surveys should
be conducted initially at a general level to identify
whether more detailed survey will be required.
Where baseline data is to be collected first hand,
careful consideration must be given to the design of
the survey and sampling programme. Data
collection must focus on the key issues needing to
be examined for the EIA (identified during the
Scoping process), and should be collected at the
appropriate time(s) of year. Consideration of likely
monitoring requirements should be borne in mind
during survey planning, so that the data collected is
suitable for use as a baseline to monitor impacts or
success/failure of mitigation measures in the future.
The need for long-term sampling should also be
assessed as early as possible. This will maximise the
time available for this to be carried out.
Data needs to be collected over a sufficiently wide
area to make sure that any effects likely to be
caused by the development can be assessed. The
area involved will not only vary for different
proposals, but for the same proposal, will vary for
each specialist type of data collected. For example,
effects on watercourses or waterbodies should be
assessed as far up and downstream as necessary to
assess and monitor beneficial or deleterious changes
in water quality or aquatic biota. The distances
involved will depend on the characteristics of any
existing discharge, of the watercourse(s) in question,
and on the location and characteristics of other
discharges affecting the watercourse(s).
2.5 Prediction of Impacts
Impact prediction must encompass both
construction and operation of the works. Impacts
should be quantified wherever possible, or fully
described if not quantifiable. The following should
be considered:
¨ magnitude of impact;
¨ duration and extent;
4 EIA Guidelines for Municipal Waste Water Treatment Works
SEAM Project
¨ whether impacts are reversible or permanent;
¨ direct and indirect effects.
Beneficial as well as adverse impacts on the
following specific aspects of the physical, sociocultural
and biological environment must be
assessed:
¨ Water quality;
¨ Social, economic and cultural environment;
¨ Waste management;
¨ Air quality;
¨ Flora and fauna;
¨ Transport and access;
¨ Hydrology and groundwater;
¨ Visual environment and landscape;
¨ Risk and hazards.
Impacts of the scheme as proposed (i.e. assuming
no mitigation) should be clearly identified, so that if
for any reason mitigation is not implemented, the
consequences will be clearly identified in the EIA.
Impacts of the scheme assuming recommended
should be identified separately. If mitigation has
already been incorporated into the design of the
scheme by the developer during the EIA process,
then the relevant identification of impacts without
mitigation may be omitted from the EIA report.
2.6 Evaluation of impacts
Criteria for evaluation of impacts must be stated.
Where possible, legislative standards or
international standards should be followed (e.g.
Egyptian Law 48 water quality standards for
discharges to the River Nile and its waterways, US
EPA guidelines for sludge reuse in agriculture, etc.).
If no suitable standards exist, descriptive criteria
may be used, but must be fully explained.
Evaluation of significance of impacts should take
account of the magnitude, duration and extent of
impact, and whether the impact is temporary or
permanent.
All predictions of impacts have an element of
uncertainty associated with them. The consultant
should identify and, where possible, quantify the
level of uncertainty associated with these
predictions. Some indication of probability of
occurrence of impacts should also be included.
2.7 Mitigation
Mitigation strategies must be considered both in
relation to individual impacts and collectively for all
impacts. Many mitigation measures can be
incorporated into the early design stages of the
project by regular communication between the
consultant and developer/designer of the works -
mitigation should be an iterative process.
Reporting of mitigation should include such specific
features which have been incorporated during the
EIA process into the planning and design of the
proposed development.
Where mitigation has not already been incorporated
into the design or siting of the proposed works
during the EIA process, or specific commitment to
mitigation measures from the developer has not
been obtained, mitigation measures should be
included as recommendations, and should be clearly
identified as such.
Recommendations for monitoring impacts in the
form of an environmental management plan (EMP)
should be included. It is not expected that a
detailed EMP be prepared for the EIA however an
outline of the content and structure and
commitment to prepare an EMP is required.
GUIDELINES FOR THE EIA
REPORT
The information provided should be clear, succinct
and objective. It should include maps, drawings,
photos, or other descriptive detail. Only data
relevant to the decision-making process should be
included.
The following sections outline suggested chapters,
subsections and contents for EIA reports on
proposed waste water treatment schemes
discharging effluent.
These guidelines include all the information
required for waste water collection, treatment, reuse
and disposal projects described in EEAA
Guidelines for Egyptian Environmental Impact
Assessment.
Writing a good report of EIA is a difficult task - it
must be technically robust, but at the same time it
must be clear, intelligible and unambiguous. Those
making a decision on the benefits and disadvantages
of a proposed development will not be technically
expert in all the areas covered by the EIA report.
The principal advice is to keep the report short, and
avoid use of technical terms unless absolutely
necessary. Technical appendices may be included as
appropriate. Suggested contents list for the EIA
report:
3
EIA Guidelines for Municipal Waste Water Treatment Works 5
SEAM Project
Table of Contents
A. Non technical or executive summary
B. Legislative framework
C. Description of the proposed development
D. Potential impacts (scoping), alternatives and
consultation
E. Description of the existing environmental
conditions within and surrounding the site
F. Prediction and evaluation of significant
environmental impacts
G. Mitigating measures and alternative processes
H. Residual impacts
I. Monitoring plan
J. Conclusions
K. Technical appendices (optional)
The non technical summary should be around 4
pages, and certainly no longer than 10 pages
(excluding plans). The main text of the EIA report
should be around 60-70 pages, and certainly no
longer than 100 pages. For more technically
complex projects, technical appendices can be used
to achieve this. Any individual technical appendix
should be no longer than 20 pages (excluding plans,
photos, drawings). The non technical summary
may be presented as a separate report.
A. NON TECHNICAL OR EXECUTIVE
SUMMARY
The summary must be written in non-technical
language to facilitate understanding by all readers. It
should be succinct and must give an overview of:
¨ What the project is;
¨ What the significant environmental impacts will
be;
¨ What has been done or is recommended to
minimise these impacts;
¨ What significant residual impacts will remain
after mitigation.
The content and structure of the summary should
broadly follow the heading structure of the EIA
report.
B. LEGISLATIVE FRAMEWORK
This chapter refers to the laws and their executive
regulations considered during the planning of the
project, e.g. Law 4/1994 on the environment, Law
48/1982 as it relates to limits of certain substances
in effluent discharges to the Nile or its waterways,
Law 102/1983 concerning natural reserves, and
other relevant laws, Governorate orders, guidelines,
etc. A list of all approvals and licences is required
under any legislation. This list should also identify
the relevant authorities involved in the assessment
and regulation of the proposal.
C. DESCRIPTION OF THE PROPOSED
DEVELOPMENT
This section of the report should be brief, and may
refer to a feasibility study carried out by the
developer or their agent. Such a feasibility report
should be summarised within the main EIA report,
and could be incorporated as a technical appendix.
The following should be covered briefly.
C.1 Objectives and Scope of the
Proposal
There should be a clear statement of the objectives
of the proposal, including rationale and/or need for
the development.
C.2 The Location
The following information should be provided:
¨ title details and land tenure;
¨ land use constraints;
¨ maps, plans or photographs and a site
description, clearly identifying the location of
the proposed development relative to:
? waterbodies;
? other land and water uses;
? other waste water treatment works and
potable water treatment works in the vicinity;
? vegetation communities;
? infrastructure, roads, utilities;
¨ compatibility of the proposal with:
? any strategy such as local management plans;
? existing land and water uses both on the site
and on adjacent land and water;
? any historical sites or environmental
protection areas.
C.3 Description and Layout of the
Proposed Development and
Associated Facilities
The following information should be provided:
¨ maximum land and water area affected by the
proposal;
¨ on-site plans, layout, photomontages or similar,
and cross sections identifying the existing and
proposed facilities (of both the treatment works
and any off site associated pipework or sewage
collection systems);
6 EIA Guidelines for Municipal Waste Water Treatment Works
SEAM Project
¨ quality and quantity of existing and proposed
effluent discharges;
¨ design/type of discharge proposed and its
location;
¨ a description of the predicted inputs to and
outputs from the works, e.g. population
equivalent to be served, predicted effluent flows,
quality and quantity of sludge and screenings
produced, method and site(s) for sludge and
screenings treatment and/or disposal, incoming/
outgoing material and vehicles during operation
of the works;
¨ a description of the size and type of the works
proposed, e.g. method and degree of both
treatment (drying, digestion etc.), number and
dimensions of treatment vessels, storage tanks,
pumps, etc.;
¨ types, quantities and storage arrangements for
chemicals used in sewage treatment (e.g.
Chlorine gas);
¨ power supply requirements and proposed
energy conservation measures;
¨ details of access arrangements and whether
these are completely new, upgraded or already in
existence;
¨ identification of drainage lines and on site
surface water management systems;
¨ employment during operation;
¨ arrangements for effluent treatment or storage
during maintenance and/or breakdown of plant.
C.4 Site Preparation and Construction
Methods
Describe the works required prior to
commencement of operations, including:
¨ any additional land requirement during
construction period;
¨ timing, staging and hours of construction work;
¨ proposed construction methods including
temporary works, the equipment to be used;
¨ methods and route of transport of the
equipment to the site;
¨ pollution control systems, e.g. erosion and
sediment control systems, wastewater holding
tanks, noise and dust mitigation strategies;
¨ import or export of material to/from the site,
including method and route of transport;
¨ any stabilisation structures or earthworks
including dredging, reclamation, excavation or
landfill, quantities of material to be moved out
of or onto the site, the method of disposal of
excess material, the sources of material to be
brought to site;
¨ details of the workforce, including source,
expected numbers and distribution throughout
construction;
¨ details of potential land contamination which
may constrain work on the site or disposal of
excess material.
C.5 Other Services in the Locality
Where applicable, outline:
¨ the capacity and type of any nearby waste water
treatment facility;
¨ the relationship of the proposed development
to previous or existing operations;
¨ past environmental performance of similar
nearby works, including impacts on the
environment and the effectiveness of any impact
mitigation.
D. POTENTIAL IMPACTS (SCOPING),
ALTERNATIVES AND CONSULTATION
The section summarises the outcome of the process
of identification and prioritisation of potential
impacts, it should include:
¨ all issues identified;
¨ the key issues which will need a full analysis in
the EIA;
¨ the issues which will not need a full analysis in
the EIA, and the reasoned assessment of why
they do not need full analysis.
A summary of the general alternatives (e.g.
alternative locations, alternative schemes) should be
given, with the reasons for the selection of the
preferred option.
The section should include details of who has been
consulted, and the outcome of such consultations.
D.1 Potential Impacts (Scoping)
Scoping of the EIA should develop from a
preliminary investigation of baseline conditions,
consultation with regulatory bodies, and a
preliminary site visit.
For waste water treatment works, the construction
phase is likely to give rise to negative impacts
regarding land take, noise, dust, traffic, and
movement into and off the site of materials -
especially large tanks, etc.
During operation of any waste water treatment
works positive impacts may occur on the quality of
a watercourse to which a works already discharges,
and on health and living standards of local
EIA Guidelines for Municipal Waste Water Treatment Works 7
SEAM Project
residents. Negative impacts on water quality of a
receiving water may also occur, if it is not currently
used for effluent disposal.
Negative impacts are likely regarding loss of useful
land to the works, odours, noise, traffic and
landscape.
Disposal of sewage sludge generated may be either
a positive impact (if of suitable quality, adequately
treated and used in agriculture), or a negative
impact (if of unsuitable quality for use in
agriculture, insufficiently treated, or disposed to
landfill or other waste disposal site). Other impacts,
both positive and negative, will occur, but will
depend on the particular site, proposal and
circumstances.
The procedures or methodology used to identify
and prioritise issues should be outlined. This should
include:
¨ relevant guidelines issued by government
authorities, provisions of any relevant
environmental protection legislation, and
relevant strategic plans or policies;
¨ relevant research or reference material, effluent
or waste water treatment studies, and relevant
preliminary studies or pre-feasibility studies.
D.2 Alternatives
The EIA should include an assessment of the
environmental impacts or consequences of
adopting alternatives, including:
¨ alternative location(s);
¨ alternative schemes and layouts of the
development and services (these may be further
developed under mitigation section);
¨ alternative management or operational practices
(these may be further developed under
mitigation section);
¨
The scoping exercise can explicitly report on what
grounds the preferred alternative was chosen. The
main part of the EIA can then concentrate on the
preferred option.
D.3 Consultation
The EIA report should included details of
consultation undertaken as part of the EIA process.
Consultees should include relevant government
agencies, NGOs, and the public. A brief description
of the reason for and the outcome of consultation
should be included.
For waste wat
regulatory powers or responsibilities concerning
planning control (including roads and traffic), waste
disposal, discharge limits to fresh waters, emissions
to air and application of sludge to land must be
consulted. Other agencies or departments might
include those responsible for historic monuments,
conservation of natural resources, etc., as
appropriate. These might include, the Egyptian
Environmental Affairs Agency (EEAA),
Governorate representatives, Ministry of Housing,
Communities and Public Utilities, Ministry of
Agriculture, Food Security and Land Reclamation,
Ministry of Transport, Communication and
Shipping, Ministry of Health, NOPWASD
(National Organisation for Potable Water and
Sanitary Drainage), and relevant Community
Development Associations (CDAs).
E. DESCRIPTION OF THE EXISTING
ENVIRONMENTAL CONDITIONS WITHIN
AND SURROUNDING THE SITE
An overview of the existing environment should be
provided in order to place the proposal in its local
and regional context, and to provide baseline data
which may be used for subsequent monitoring.
General information to be provided for specific
issues identified as potentially important in the
assessment of impacts from waste water treatment
proposals is discussed in the following subsections,
and includes:
E.1 Water quality and hydraulics;
E.2 Socio-economic and cultural environment;
E.3 Waste management;
E.4 Air quality;
E.5 Flora and fauna;
E.6 Transport and access;
E.7 Hydrology and groundwater;
E.8 Visual environment and landscape;
E.9 Risk and hazards.
Data must be specific to the proposed site, rather
than general information on a particular area, and
the EIA should only deal with issues relevant to the
proposal being assessed. Each issue and the level
of detail should match the level of importance of
the issue in decision-making. To make the EIA
report easier to read, it may be sensible to include
the specialist detail for each of the following
sections as a technical appendix to the report, with
a summary of each section in the main EIA report.
E.1 Water Quality and Hydraulics
As improvement in water quality is usually the
driving force for provision of waste water
treatment, this aspect of the environment is of
primary importance in the EIA. Discussion should
8 EIA Guidelines for Municipal Waste Water Treatment Works
SEAM Project
focus on those water quality characteristics that may
alter, and on the assimilation capacity of the water
body to which the proposed works will discharge.
Both positive and negative changes in water quality
will need to be quantified, and therefore baseline
data will be required. The existing microbiological,
chemical, biological and hydraulic conditions in the
water body to which the works currently discharges,
and if not the same, to which it will discharge
should the development be approved, must be
assessed. Baseline data collected should be
sufficient that predicted conditions should the
development be approved may be calculated.
The following water quality indicators and hydraulic
conditions must be assessed for both the existing
and proposed effluents, and for both water courses
to which the works will discharge, and for any water
course affected by existing discharges:
¨ faecal coliforms (as indicators of faecal
contamination),
¨ levels of dissolved oxygen and Biochemical
Oxygen Demand,
¨ particulate matter (increased turbidity and
reduced light penetration),
¨ chemical contaminants from likely industrial or
agricultural sources such as metals, biocides and
hydrocarbons;
¨ aquatic biological indicators (invertebrates);
¨ nutrients (nitrogen and phosphorus).
¨ water quantity (daily inflow for small treatment
works, dynamic inflow conditions for black list
treatment works (see section 2.2))
Data should be obtained from sufficiently far
upstream of the proposed discharge (and existing
discharge, if any) to be able to estimate background
conditions for the area/length of the watercourse
affected, or likely to be affected should the project
be approved. Care should be taken that no other
discharges exist between the proposed discharge
point and the point used for sampling background
conditions. Samples should be taken as far
downstream to permit assessment of the distance
over which the discharge will be assimilated by the
water course, or to the next discharge downstream if
any.
Scoping should identify what may be likely sources
of industrial contaminants in the catchment area,
which may then require baseline measurement or
monitoring.
As well as the obvious direct changes in water
quality due to a changed or new effluent discharge,
changes could result from secondary or cumulative
effects of the development (during construction
and/or operation). Points to consider include:
¨ accidental, deliberate or managed discharge or
release of materials,
¨ individual sources of change from works
construction (e.g. spillage of fuels, suspended
solids such as cement dust, lubricants, etc.),
¨ activities that alter flow regimes, erosion and
sedimentation patterns and water chemistry,
¨ run-off from site and road areas.
For large size projects or projects in ecologically
sensitive areas, it is highly recommended that the
evaluation of the environmental impact for larger
treatment works, i.e. categorised in the high end of
the grey list projects and all black list projects, are
analysed on the basis of a dynamic model.
The modelling activity should preferably encompass
the water quality and hydraulic conditions for the
catchment (the sanitary drainage system), the
treatment works and the receiving body. The
modelling activity must consider both the existing
and planned (future) conditions. It is
recommended that the modelling of the existing
conditions are validated against field measurements.
E.2 Social, Economic and Cultural Issues
Social impacts of waste water treatment schemes
are often indirect and complex to assess, and
consequently often not adequately addressed in
EIA. Baseline data collection should cover the
following:
¨ existing health of the local population (in
quantitative terms where possible) which may be
affected by provision or change to waste water
treatment or collection (e.g. local incidence of
water borne diseases);
¨ existing potable water usage of the community,
which may be affected after provision of waste
water collection and treatment system;
¨ existing charging structure and cost of waste
water disposal, which may be affected by
provision of different waste water collection and
treatment systems;
¨ impacts of existing waste water disposal
systems which may be affected by provision of
different systems;
¨ existing and projected water treatment facilities
for potable supply, which may be affected by
provision of different waste water collection and
treatment systems;
EIA Guidelines for Municipal Waste Water Treatment Works 9
SEAM Project
¨ local employment conditions which may be
affected during construction and operation;
¨ existing economic situation which may be
affected by provision of different waste water
treatment, especially concerning:
? other developments,
? land values,
? agriculture,
? tourist facilities;
¨ identification of items or sites of cultural or
historical significance likely to be affected by the
proposal, and an assessment of their cultural
and/or financial importance.
Areas or sites of particular social or cultural
importance or sensitivity should be plotted on maps
or diagrams, shown in relation to the proposed
development.
E.3 Waste Management
Disposal of waste products is an important aspect
of EIA for waste water treatment works, which is
often omitted or not fully investigated. Data on
existing and proposed waste management systems
should include:
¨ likely opportunities for re-use of sewage sludge
and/or effluent (e.g. availability of agricultural
land, attitudes towards use of sewage sludge in
agriculture, ease of distribution of sludge to end
users, legislative requirements for such re-use);
¨ potential sites and routes for disposal of sewage
sludge if unsuitable for re-use in agriculture, and
quality required of sludge for disposal;
¨ potential sites and routes for disposal of
screenings waste;
¨ potential disposal sites and routes for excess
material from the site during construction.
E.4 Air Quality
Air quality is likely to be significantly affected by
any waste water treatment works proposal, both
during construction and operation. Likely major
issues include dust sources during construction, and
odours and aerosols produced during operation of a
treatment works. Noise generated during
construction is also likely to have a significant
impact if the proposed site is near centres of
population, or if construction of a waste water
collection system is included within the proposals.
Assessment of baseline conditions should include:
¨ identification of sources of existing odours at or
near the proposed site;
¨ identification of sources of existing dust
generation which may affect the proposed site;
¨ identification of sources of existing noise which
may affect the proposed site.
¨ collection of meteorological data which will
affect distribution and severity of air quality
impacts, in particular:
? strength and direction of prevailing wind
? rainfall frequency, duration and quantity.
¨ collection of topographical information which
will affect distribution of air quality (e.g. steep
slopes, presence of tall vegetation)
¨ identification of sensitive receptors (e.g. schools
and hospitals which may be affected by odours,
dust and noise; important crops or natural areas
which may be affected by dust and/or noise)
within the area likely to be affected by improved
or deteriorating air quality.
Consideration should be given to providing
modelling studies to determine the likely
distribution of odours, dust and noise during
operation of the works.
E.5 Flora and Fauna
Terrestrial and/or aquatic flora and fauna or their
habitats which are likely to be disturbed or
obliterated during construction or operation of the
project must be identified and their importance
evaluated. As a general rule, distribution data
should be presented as habitat or species location
maps, shown in relation to position of the proposed
works. Data collection and surveys should include:
¨ identification, description and distribution of
areas of terrestrial and aquatic habitats that may
be directly or indirectly affected especially those:
? supporting threatened or protected species or
habitats;
? of commercial importance (e.g. for
agriculture, aquaculture or fisheries);
? of nature conservation or scenic importance.
¨ assessment of the importance of the habitats or
species identified above, in terms of
International, National, Regional or Local
importance.
E.6 Transport and Access
Information to allow assessment of potential
transport and access impacts should include:
¨ assessing condition and size of roads on
route(s) to be used during construction and
operation of the development;
10 EIA Guidelines for Municipal Waste Water Treatment Works
SEAM Project
¨ assessing existing traffic levels on these routes,
at different times of year and times of day;
¨ assessing suitability of access to the site for
vehicle sizes and types likely to be used during
the construction and operation of the scheme;
¨ investigation for the presence of particularly
sensitive developments on routes likely to be
affected, e.g. schools on construction or
operational routes.
A detailed traffic study may be required where
vehicle movements are likely to significantly affect
the community.
E.7 Hydrology and Groundwater
Hydrological issues to consider which may either be
affected by the development, or affect the
development itself include:
¨ existing drainage patterns, including the
location of wadis and identification of areas
prone to flash floods, the range of water
heights/depths in the area, daily flushing regime,
storm surge or flood levels;
¨ groundwater regime and quality, e.g. depth to
groundwater level, whether groundwater is used
for water supply and its quality, whether control
of groundwater is already exercised in the area;
¨ presence and importance of structures likely to
be affected by changes in groundwater levels
(such as buildings, bridges, flood mitigation
works).
For larger treatment works, it is highly recommended
that the hydrology and ground water conditions are
analysed on the basis of a numerical model.
E.8 Visual Environment and Landscape
The nature of the existing visual environment and
landscape should be assessed for their sensitivity to
impacts such as changed or obstructed views.
Particularly sensitive receptors likely to be affected in
the vicinity should be identified, such as tourist
establishments, prestigious developments, schools, etc.
E.9 Risk and Hazards
Existing potential hazards to identify, and if
possible to quantify, which may affect or be
affected by the proposals, include:
¨ storage and handling of hazardous materials;
¨ likelihood of release of chemicals, natural
occurrences such as floods, storms, landslip, fire,
explosion.
F. PREDICTION AND EVALUATION OF
SIGNIFICANT ENVIRONMENTAL IMPACTS
This chapter should include a discussion of impacts
during both construction and operation of the
proposed scheme. Impacts of different aspects of
the proposed scheme on the above sectors of the
environment should be considered separately.
Criteria for evaluation of the significance of impacts
should distinguish between impacts which are:
¨ positive and negative;
¨ reversible and irreversible;
¨ short term and long term;
¨ direct, indirect or cumulative.
Criteria should be based on local legislative
standards wherever possible. Where these are not
available, acceptable international standards should
be used (e.g. WHO, US EPA, etc. guidelines). In all
cases the choice of the appropriate standard must
be robust and defensible. If no suitable standard is
available, then the criteria developed and used must
be clearly explained in the EIA.
Use of matrices can be very helpful in co-ordinating
and summarising information for this section of the
EIA report.
For this section of the report, impacts should be
considered before or without mitigation, unless
particular mitigation is already incorporated into the
design and development description included in the
earlier part of the EIA report.
Examples of potentially significant impacts of waste
water treatment developments include (but are not
restricted to):
¨ positive impacts on water quality, health of
local population, aquatic flora and fauna
currently affected by untreated or inadequately
treated discharges;
¨ negative impacts on flora and fauna or local
inhabitants by occupation of site or direct
removal of habitats of nature conservation,
agricultural or aquacultural importance;
¨ positive impacts by provision of sewage sludge
for use in agriculture, or this impact could be
negative if the sludge is not adequately treated;
¨ negative indirect effects, e.g. dust generated
during construction affecting crop growth,
damage to crops by spillages or leakage onto
adjacent land or into irrigation waters.
¨ positive effects on local economy allowing
rapid development, by provision of waste water
treatment. This impact could also be negative if
increased flows to the waste water treatment
works resulted in there being inadequate capacity
to treat additional waste waters generated.
EIA Guidelines for Municipal Waste Water Treatment Works 11
SEAM Project
G. MITIGATING MEASURES AND
ALTERNATIVE PROCESSES
This section considers mitigation measures and
strategies to reduce negative impacts on different
sectors of the environment. Mitigation must be
sustainable, integrated and feasible.
Some mitigation measures should be implemented
at a very early stage of design of the works easily,
but are difficult or expensive to implement once
early design has been completed. Therefore it is
vital that any mitigation should be discussed and
developed in consultation with the developer and
regulatory authorities throughout the EIA process.
This section of the EIA report should therefore be
a summary of any mitigation already implemented
in the ongoing design of the facility, and also
include any recommended mitigation strategy to be
implemented during construction and operation of
the works.
This section may also include any enhancement
measures for which there is a commitment from the
developer, which will enhance any positive impacts
of the development. This may include measures
such as planned public education programmes in
the use and operation of water collection and
treatment systems.
Suitable mitigation for waste water treatment works
will depend on the design and layout of the works,
as well as the local environment, and location.
Examples of measures to reduce negative impacts
may include, but will not be restricted to:
¨ relocation of a discharge to obtain greater
dilution and/or avoid particularly sensitive
habitats;
¨ alteration to treatment method to obtain higher
quality of effluent;
¨ provision of larger areas for sludge drying beds
to ensure adequate drying so that sludge can be
safely re-used in agriculture;
¨ paving of roads to reduce erosion by traffic;
¨ re-routing of construction traffic to avoid
sensitive developments such as hospitals;
¨
reduce dust damage to nearby crops;
¨ provision of by-passes or parallel treatment
systems to avoid untreated or partially treated
effluent being discharged to watercourse during
maintenance or plant breakdown;
¨ restrictions to working hours or changes to
methods of working to avoid dust/odour/noise
nuisance to local inhabitants.
H. RESIDUAL IMPACTS
This section should give a summary of those
impacts which will remain assuming mitigation has
been implemented. It will therefore include those
impacts for which there is no suitable or only low
levels of mitigation, and positive impacts.
Assuming all suitable mitigation has been
incorporated into the design, or recommended and
will be implemented, for waste water treatment
works these are likely to include, but not be limited
to:
¨ improvements to water quality of receiving
waters;
¨ availability of treated sewage sludge for use as
fertiliser;
¨ improvements in local health due to reductions
in water borne diseases;
¨ slightly increased local employment to operate
the waste water treatment works;
¨ occupation of land formerly occupied by
agriculture, natural environment or
development;
¨ temporary disruption during construction;
¨ visual impact of waste water treatment works.
I. MONITORING PLAN
This program should be carefully designed and
related to the predictions made in the EIA and the
key environmental indicators. This should be
designed to demonstrate the potential ecological
sustainability of the proposal. The EIA should
outline the need for, and use of any proposed
monitoring plan, its duration and reporting
procedures, define suitable criteria for monitoring,
and actions to be taken in the event of noncompliance
with these criteria.
Parameters which may be relevant include:
¨ performance indicators in relation to critical
operational issues including:
? water quality,
? sludge and screenings (quality and quantity),
? noise and air quality,
? public health indicators,
? flora and fauna.
¨ monitoring of complaints received.
Commitment to monitoring may be demonstrated
by production of an environmental management
plan. This is a document designed to ensure that the
commitments in the EIA, subsequent assessment
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SEAM Project
reports, and approval or licence conditions, are fully
implemented. This should demonstrate that sound
environmental practices will be followed during the
construction and operation of the development. It
should cover the following:
¨ management of construction impacts, (e.g.
disposal of waste material, re-vegetation
management plans);
¨ management of operational impacts, (e.g.
effluent and sludge quality and quantity
management, plant maintenance plans,
hazardous materials and fuel management,
transport management, site security plans,
emergency and contingency plans);
¨ strategies and action plans to feed information
from the monitoring program into the
management practices;
¨ Public awareness and training programmes for
operational staff;
¨ indicators of compliance with licensing and
approval requirements.
The Environmental Management Plan should
describe the following monitoring details:
¨ the key information that will be monitored, its
criteria and the reasons for monitoring (e.g.
limits of parameters such as BOD, faecal
coliform bacteria, suspended solids, Ammonia
and nutrients to be achieved in the effluent);
¨ the monitoring locations, intervals and duration
of monitoring (e.g. sample for analysis of faecal
coliforms to be taken 10m upstream of
discharge, discharge itself, and 10m downstream
of discharge, once per week);
¨ actions to be undertaken if the monitoring
indicates a non-compliance with the defined
criteria or an abnormality (e.g. inform WWTW
site manager in writing of parameter exceeded
and expected action to be undertaken);
¨ internal reporting procedures and links to
management practices and action plans (e.g.
WWTW site manager to review and remedy
disinfection processes if faecal coliform levels
are above the specified maximum);
¨ reporting procedures to relevant authorities
and, if appropriate, to the consent authority or
the community.
J. CONCLUSIONS
This should be a summary of sections F, G and H
of the report (prediction and evaluation of impacts,
mitigation and alternative processes, and residual
impacts), to emphasise:
¨ which impacts are likely to be significant;
¨ how significant they will be;
¨ which parts of the environment are likely to be
affected;
¨ whether mitigation is possible;
¨ the likely success of mitigation measures adopted
or recommended to alleviate those impacts.
This information can be presented either as text, or
as summary tables, if desired.