Applied Geography (1983), 3, 5-27
Environmental impact assessment
Norman Lee Department
The University, Manchester
Ml3 9PL, England
Abstract The review is divided into two main sections. The first section contains a survey of the growth in the use of EIA during the 1970s in Western industrialized economies, Third World countries and international agencies. It highlights a number of key issues associated with these developments-notably the types and numbers of actions which should be submitted to EIA, and the quality of EIA studies and the time and cost incurred in their preparation-and recommends that the focus of future development should be directed towards a more cost-effective ‘tiered’ system of environmental impact assessment. The second section contains a review of the technical methods which are used in the preparation and publication of EIA studies. These are grouped according to the kind of task they perform in the EIA process: identification, data assembly, prediction, evaluation and communication. This review concludes with recommendations for improvement in the EIA methods in use in such areas as: clearer identification of ‘best existing practice’, publication of technical guidance based on best practice, provision of training facilities in the use of EIA methods, and re-examination of priorities in environmental monitoring and research.
Introduction Although environmental factors have been taken into account in development control and land-use planning in a number of countries for many decades, environmental impact assessment (EIA) in its modern form is a creation of the 1970s. In this modern form it may be defined as a process by which an action, that requires the approval of a public authority and which may give rise to significant environmental side effects, is submitted to a systematic environmental evaluation, the results of which are then taken into account by the public authority in deciding whether or not to approve it. The ‘action’ may take many forms : the approval of new development projects, programmes, plans or policies. To date, most actions submitted to EIA have fallen within the first of these categories. The origins of EIA lie in the National Environmental Policy Act (1969) which came into operation in the United States on 1 January 1970. Section 102(c) of the Act requires that each federal agency should: include in every recommendation or report on proposals for legislation and other major federal actions significantly affecting the quality of the human environment, a detailed statement by the responsible official covering, infer alia, the environmental impact of the proposed action and of alternatives to it.
This environmental impact statement of which the essential features are:
(EIS) forms an integral part of an EIA procedure
& Co (Publishers)
1. A draft EIS should be prepared and made available prior to the first significant point of decision in the public authority’s authorization process. 2. The public authority should consult with, and (on the basis of the draft EIS) obtain the comments of, the public and other public bodies with jurisdiction or special expertise relating to the environment involved, on the environmental impact of the action. 3. A final version of the EIS should be prepared, which incorporates the substantive comments of the public and the public bodies consulted, and this should accompany the proposed action through the remainder of the public authority’s authorization procedure (Council on Environmental Quality 1973). Although certain aspects of this EIA system have been revised (Council on Environmental Quality 1978) following six years’ experience of its operation (Council on Environmental Quality 1976), its basic elements have remained the same. These are: the preparation and publication of an initial environmental impact study relating to the proposed action; consultation and public participation based upon that study; the preparation of the final form of the environmental impact study and its integration within the decision-making process of the authority competent to approve the action. In little more than a decade since NEPA was passed, some form of EIA has been, or is in the process of being, adopted by the great majority of Western industrialized countries, an increasing number of Third World and Eastern European countries and by a substantial number of international agencies. The detailed form of these EIA provisions varies considerably between countries but many of their basic elements correspond closely to the NEPA model. The extension of EIA in this way is of considerable long-term significance to the development and practice of environmental policy. In the first place, it reinforces the growing emphasis now placed on the anticipatory element in environmental policy; that is, it strengthens the use of forward environmental planning as a means of reducing the number and severity of environmental problems which have to be resolved after development has taken place. It also encourages the closer integration of environmental planning with other forms of economic and social planning. The need for greater compatibility between these different forms of planning has become more pressing in the more difficult economic conditions of the 1980s. Secondly, provisions for the publication of EIA studies and the requirement for consultation and public participation in their evaluation reinforce the trend towards more openness at the different stages of environmental planning and decision-making. As such, it will tend to make other forms of planning and decision-making which have environmental consequences more open to public consultation. At the same time, these developments create a communication challenge to technical specialists whose analyses of complex diverse impacts upon the environment must be presented in a way that is meaningful to a critical but possibly technically unsophisticated readership. Thirdly, the growth in the use of EIA involves the preparation of considerably more systematic and comprehensive environmental studies and this creates a need for additional, better quality data and for appropriately trained technical staff to undertake their analysis. These studies are interdisciplinary, incorporating economic and technological as well as environmental knowledge; they cover all environmental media which may be affected by economic and technological change; and they draw upon a variety of different kinds of technical skill in their preparation. Therefore, they are likely to stimulate new developments in environmental monitoring and data storage, in interdisciplinary forms of research and in more broadly based technical training to meet the different types of needs which EIA is generating.
It is against this background of the growing use of EIA and its longer-term significance that this review has been prepared. It is divided into two main sections: 1. Scope and procedures of EiA systems: the main similarities and differences in the systems adopted at national and international level are reviewed; and certain key issues are examined relating to the types of actions submitted to EIA, and the efficiency of the procedures by which EIA is implemented. 2. EZA methods: the assessment tasks and assessment methods used in EIA are reviewed; and the main deficiencies in current practice and scope for improvements are examined. The review concludes with a summary of the main suggestions made for improving EIA practice, both in relation to the scope of EIA systems used and to the technical methods employed in the preparation of EIA studies. Scope and procedures
A very large number of countries claim to be practising EIA or to be contemplating doing so in the near future. However, countries often differ in their notion of what constitutes EIA. In some instances EIA is being interpreted in the rather general form of ‘taking environmental factors into consideration in decision-making’, without requiring the preparation and publication of a systematic environmental evaluation of a proposed action or a structured system of consultation based upon this study. For this reason, although the growth in the use of EIA has been very rapid, a number of the EIA systems now in operation do not meet all of the requirements of a fully fledged system as outlined in the Introduction. EIA systems also differ in their coverage, that is, in the categories of action and in the proportions of actions within each category which are submitted to EIA. A country may possess a fully fledged system but only apply it to an extremely small number of actions. A further source of variability is in the legal status of EIA systems. In some countries, like the USA and France, EIA has been introduced through new environmental legislation. In other cases, like Canada and the Federal Republic of Germany, it was introduced by cabinet decision which left a greater measure of discretion in the form of its implementation. In yet other countries, like the United Kingdom, it has been introduced by strengthening or modifying practice within existing environmental planning, or other forms of, legislation. For these reasons the provisions for EIA vary considerably between countries and are also varying over time. The review which follows is divided into two parts: first, there is a brief survey of some of the principal examples of EIA systems in different parts of the world, notably in North America, Western Europe and in the Third World which, in turn, are closely related to the EIA practice of a number of international funding agencies; and second, an examination of a limited number of ‘key issues’ which are raised by that survey. EIA survey North America. The National Environmental Policy Act (1969) introduced into the United States a formal EIA system for federal-level actions. Under these provisions a very large number of EISs have been prepared (over 10 000 had been filed by 1980), the great majority of which relate to individual development projects to be carried out in the public sector (Council on Environment~I Quality 1980; Liroff 1981). These federallevel provisions have been supplemented by provisions for EIA at state and city levels (by 1980, 29 states and a number of cities had adopted such measures). Following a
impact assessment: a review
comprehensive review of the operations of NEPA in 1976 (Council on Environmental Quality 1976), a number of modifications have been made to the federal system, notably to reduce the number of development projects for which EIA is obligatory, to reduce paperwork and delays, to improve the quality of the EIA process and to encourage the greater use of EIA when approving policies and programmes (Council on Environmental Quality 1978). By contrast, a federal-level EIA system was introduced into Canada in 1973 by cabinet decision. This required the Minister of the Environment to establish a process for the environmental impact assessment of federal projects, programmes and activities, as well as of private projects involving federal lands, properties or finance (Hurtubise and Wolf 1980). This was modified by a further cabinet decision in 1977, which was later incorporated into the Government Organisation Act (1979). This EIA system involves three stages of analysis-initial screening, initial environmental evaluation, and formal assessment by an Environmental Assessment Panel-and only a small minority of actions are required to proceed through the third stage. Between 1974 and 1980, only 25 major projects had been referred to a Panel for a formal assessment, which involved the preparation and publication of an EIS and a public review of the same. As in the United States, a number of individual provinces have introduced EIA provisions to apply to lower level projects. EEC. The first member state of the European Communities to initiate an EIA policy was the Federal Republic of Germany. In its 1971 Environment Programme, the federal government proposed making ‘examination for environmental compatibility’ an essential component in the preparation of a wide range of federal measures. A ‘Model Procedure’ was subsequently developed by the Ministry of the Interior and adopted by cabinet resolution in 1975. However, this only contains guidelines for the use of EIA in the administrative practices of individual ministries and does not meet all of the requirements of a fully fledged EIA system (Kennedy 1980). Some EIA provisions relating to state-level actions have also been made in a number of Lander. In 1976 two member states, France and Ireland, made statutory provision for EIA, although the coverage of each system is very different. In France, the Protection of Nature Act (1976) provides that studies undertaken prior to commencing significant public works or private works requiring public authorization must include an impact assessment study. Subsequent application decrees have detailed the coverage, content, provision for public participation, and other aspects of the study. During 1978 over 4000 impact studies were completed (Ministere de 1’Environnement 1980). In Ireland, the Local Government (Planning and Development) Act of 1976 provides for the preparation of a written environmental impact study as part of the development control procedure for large private sector projects. However, the planning authorities have discretion in determining whether to insist upon the preparation of such a study in any particular case and, to date, very few studies have been formally required. In the Netherlands, draft EIA legislation was presented to Parliament in 198 1 based on the government’s previously published ‘Standpoint’ on EIA (Ministry of Health and Environmental Protection 1980). The proposed Dutch system includes certain policies and plans as well as development projects and these will be incorporated into the ‘positive lists’ of actions subject to EIA which are being prepared. At the same time it is recognized that the number of studies which can be undertaken in the early years following implementation is limited and it is planned to restrict these to ‘several dozens’ in the initial period. A special feature of the Dutch proposals is the provision for independent review of the environmental impact study, as well as for consultation and public participation (Jones 1980).
In the United Kingdom, a considerable number of official studies and professional bodies have accepted the desirability of some form of EIA system (Wood 1982). The government also supports the use of environmental assessment studies for major developments which may have complex and important consequences for the environment. However, their preference is for a non-mandatory system, operating within the existing planning legislation. We must avoid legislation which could be difficult to enact, hard to implement and, by virtue of its uncertainty, a source of litigation and dispute (House of Commons 1981).
To date a considerable number of environmental impact studies have been prepared and used within the development control system or for related purposes, although these have not always met the requirements of a fully fledged EIA system. Whilst these and other developments have been taking place at the level of the individual member state, the Commission of the European Communities has been preparing its own EIA proposals and these were submitted to the Council of Ministers in the form of a draft directive in June 1980 (Lee and Wood 1980a). This contains a common set of broad requirements and guidelines relating to the types of development projects to be subject to EIA, the preparation and publication of environmental and impact studies for these, consultation and public participation, and the integration of the studies and comments upon these into the decision-making processes for the actions concerned. The detailed interpretation and application of these requirements and guidelines will largely lie within the competence of the individual member states. A lengthy process of consultation over the provisions of the draft directive is under way; a favourable opinion has been given by the Economic and Social Council and the European Parliament, and the detailed text is currently being examined by a working group established by the Council of Ministers. In addition, a number of non-EEC countries (for example, Norway and Sweden) now possess legislation which enables EIA to be used in project authorization and others (for example, Spain, Switzerland) have draft legislation pending. There is also considerable interest in EIA in a number of Eastern European countries (for example, Poland and USSR) where certain of the basic elements of EIA have been incorporated into plan-making activities. Third world and international agencies. At present, only a limited number of Third World countries are using EIA but their numbers are growing (de Souza 1980). A number of Latin-American countries (for example, Brazil and Mexico) possess some EIA procedures which are used in cases where major development projects are expected to have a significant impact. Other developing countries possessing some elements of an EIA system are the Philippines, Korea, Thailand and Malaysia. In part, the use of EIA (in the Third World and elsewhere) is likely to grow because of the favourable attitude adopted by the major international organizations and other aid-giving agencies. The United Nations Environment Programme has played a specific role by developing EIA guidelines for use in the siting of industrial developments (UNEP 1980). These were initially prepared by Atkins Research and Development and have been elaborated and refined through a programme of international workshops. OECD, FAO, WHO, the Council of Europe and the Economic Commission for Europe have all supported the use of EIA (Economic Commission for Europe 1979). In addition, a number of aid-giving agencies require the use of some form of environmental evaluation in the appraisal of projects to be funded within their aid programme (de Souza 1980). This was extended in 1980 when the
Environmental impact assessment: a review
World Bank, five regional development banks, the Commission of the European Communities, the Organization of American States, the United Nations Development Programme and the United Nations Environment Programme were signatories to the Declaration of Environmental Policies and Procedures relating to Economic Development. They then pledged themselves to systematic examination of all development activities with a view to taking appropriate measures for the protection and improvement of the environment, and to provide support facilities to developing countries in the form of technical and training assistance on environmental matters and research to improve the use of environmental evaluation within project appraisal. Key issues The remarkable expansion in EIA over such a relatively short period of time has not been without its difficulties nor its critics. Following the growth of the 1970s the present decade provides the opportunity for consolidation in which the role of EIA in the planning and implementation of new developments is more clearly identified and the procedures and methods by which EIA is executed become more efficient. Some of the key issues which need to be considered during this consolidation phase are briefly examined below. Types and numbers ofactions submitted to EIA. The above review shows that, to date, EIA has been restricted mainly to the evaluation of individual development projects. This is partly due to technical considerations (EIA is believed to be easier where the properties of the proposed action can be identified in greater detail) and partly to the existence in many countries of project authorization procedures into which EIA could be relatively easily integrated. The main limitation of this approach is that possible alternatives to the proposed action may be systematically investigated only at a relatively late stage in the planning process when certain of the more important options have been foreclosed. As a result, the view is now growing that EIA of projects should be supplemented by the earlier environmental impact assessment of policies, plans and programmes in a ‘tiered’ EIA system (Lee 1982). The extension of EIA to other categories of action is envisaged in the USA and the Netherlands, in a number of Eastern European and Third World countries and by certain international organizations. In the Action Programme (1982-86) of the Commission of the European Communities it is proposed to explore the possible use of EIA in the evaluation of physical planning schemes, economic and regional development programmes and new technologies. This will stimulate further interest in the development of EIA methods more appropriate to these different kinds of actions. At present there are considerable differences between countries in the proportion of development projects which they submit to EIA. The underlying difficulty is one of striking the correct balance between trying to establish a reasonably comprehensive system and the need to tailor any system to the technical and administrative resources likely to be available. An approach which is now increasingly favoured is to draw a less rigid distinction between actions to be subject to EIA and those that are not. This can be achieved in a variety of ways: using thresholds for particular types of action, carrying out initial evaluations to screen doubtful cases, and permitting simplified assessments where actions result in less complex or significant impacts. In these circumstances a reasonably comprehensive scheme may still be practicable provided it entails only a limited number of full-scale studies each year. Quality, time and costs of EIA. Determining
the general quality of EIA studies is difficult
for two reasons. First, the evidence that is available is mainly in the form of published EIA reports and the assessments made on this basis may relate more closely to the way in which the study findings are presented than to the conduct and content of the study itself. Secondly, there is not yet complete agreement on the criteria by which the quality of such studies should be evaluated. However, despite these difficulties, most observers agree that there is great variability in the quality of the EIA studies which have been completed so far. This state of affairs is probably mainly due to the following: (a) in certain countries, attempting to undertake too large a number of studies in the early years immediately following the formal introduction of an EIA system; (b) inadequate preparation in the form of technical guidance and training in the correct use of EIA methods. There is now a much greater awareness of these problems than there was in the early 1970s and it is now more likely that new EIA systems will be implemented initially on a more restrictive basis and that this will be preceded by the preparation of technical guidelines on assessment methods and some preliminary training in the use of these. Nevertheless, as indicated more fully in the second half of this article, there is a considerable further effort required to bring the general standard of EIA studies nearer to the ‘best practice’ standard which is currently attainable. Another major concern in the early years following the implementation of NEPA (1969) was that EIA would cause delays in the authorization of new development projects. In general, this fear has not been realized. Particular cases have been cited where EIA has been associated with a delay in approving a project but on closer examination it has often been found that the responsibility for this did not lie in the EIA system itself-for example, where it was due to inadequate preparatory work by the developer or to delays in the competent authority reaching a decision after the EIA process had been completed (Goldsmith 1974). By contrast, some industrial developers have found that the adoption of EIA procedures has led to a substantial shortening in the period of time taken in obtaining authorization (Dean 1979). In the Netherlands it is hoped that the introduction of EIA will save time by eliminating the duplication of documentation and consultation which currently arises when a developer has to apply for permits and licences to a number of different planning and environmental authorities (Ministry of Health and Environmental Protection 1980). In fact, most new EIA systems are now being constructed on the assumption that they should not normally add to the delay in reaching decisions on complex and controversial development proposals, and preferably they should be time-saving. The total net costs of applying the EIA process to individual development projects are difficult to estimate because of problems in measuring the indirect costs and savings which may incidentally result from its use in any particular case. The direct costs of preparing the EIA study vary with the size and complexity of the development and with the quantity of relevant, base-line, environmental data which is already available. However, in the case of reasonably large projects, these study costs are typically less than 1 per cent of the total capital cost of the project (Ministry of Health and Environmental Protection 1979; Weiner 1980) which also represents a minor share of the total planning and development costs of a typical project. The indirect costs and benefits are potentially of greater significance: notably the effect of EIA on the timing of the implementation of the project and on the type of development which is finally authorized. As indicated already, the first of these indirect cost items should, in a wellstructured system, be small or even negative. Similarly, other studies have shown that well-prepared EIAs can result in capital cost savings (for example, through a critical
re-examination of the demand forecasts used to justify the project and of the types of process technology which it is proposed to use) (Cook 1979). Where the EIA leads to additional expenditure to overcome previously unidentified environmental problems, these are commonly less than the costs that would have to be incurred if such problems had come to light only after construction and operations had commenced. Given these possibilities, much more attention is being given to the potential cost savings which may be achieved through EIA and, consequently, to the cost-effectiveness of both the EIA procedures and methods which are used. Methods of assessment In the early years following the implementation of NEPA there was an understandable desire to devise new technical approaches to environmental impact assessment. During this period a number of new ‘integrated methodologies’ were developed which were subsequently given considerable prominence in the EIA literature and these are sometimes regarded as the most distinctive modern feature of environmental impact assessment (Canter 1977; Munn 1979; Clark et al. 1980). Almost certainly their significance has been exaggerated. On examination they are usually found to be less comprehensive in their scope than originally envisaged since they concentrate upon certain assessment tasks in the EIA process to the relative neglect of others. They have also encountered serious problems in handling the value judgements involved in assessing the ‘significance’ of impacts. For these and similar reasons, as recent surveys have revealed, the practical use made of them has been fairly limited (Environmental Resources 1981). Therefore improvements in assessment practice are more likely to be obtained by better selection and use of existing methods suited to particular assessment tasks, followed by careful integration of the results obtained, than by developing newer forms of integrated methodologies. The review which follows is based upon this premise. It begins by considering the tasks involved in carrying out an EIA study and the criteria by which methods should be selected to perform these tasks. This shows that there is no single integrated methodology which meets all requirements: the constituents of the most appropriate approach will vary according to the type of project and the circumstances in which the assessment will take place. The review continues by examining five types of methods, grouped according to the type of task they perform, viz. identification, data assembly, prediction, evaluation and communication. In each case attention is paid to weaknesses in assessment practice and to the means of overcoming them. Table 1 contains a classification of the main tasks involved in preparing an environmental impact study for a development project (Lee and Wood 198Ob). The table is not intended to indicate the strict chronological order in which tasks are performed. For example, alternatives to the preferred development should be identified and their impacts investigated in a preliminary way at a very early stage in the study. Similarly, the examination of the preferred development may pass through a number of ‘cycles’ of investigation as successively more detailed analysis is focused upon a narrower range of potentially significant impacts. Hence the process of investigation is cyclic rather than linear. Assessment methods can be grouped according to the type of task which needs to be performed, recognizing that any one type of task may occur at a number of different stages in the assessment process. The main groupings are: 1. Identification methods-to assist in ~~ent~ying the project alternatives, project characteristics and environmental parameters to be investigated in the assessment.
Data assembly methods-to assist in describing the characteristics of the development and of the environment that may be affected. Predictive methods-to predict the magnitude of the impacts which the development is likely to have on the environment. Evaluation methods-to assess the signijcance of the impacts which the development will have on the environment. Communication methods-to assist in consultation and public participation and in expressing the findings of the study in a form suitable for decision-making purposes. Table 1 also contains examples of each of these types of methods and the particular assessment tasks for which they may be used. For any given task there are likely to be a number of alternative methods available and criteria are needed to assist in choosing between them. First, the method selected should be appropriate to the task in the sense that it should supply the information required in the appropriate form and with the necessary degree of detail and accuracy. In the early stages of analysis, simple methods which yield only approximate results may be sufficiently accurate to screen out the relatively unimportant variables from the
Table 1. A classification system for EIA methods Tasks
I. Description of proposed development (a) Identify aspects of project for which information is to be sought distinguishing, where necessary, between different stages in the proposed development (e.g. construction and operating phases) and between different levels of screening (b) Determine resources to be used in construction and initial operating phase, wastes to be created, physical form of the development (c) Forecast future resource use, waste generation, etc., over the expected life of the development 2. Description of existing and projected environmental conditions (a) Identify aspects of existing and projected environmental conditions for which information is to be sought
(b) Collate existing environmental identify gaps in information
(c) Obtain additional environmental meet remaining deficiencies
(d) Predict future environmental conditions (without the proposed development)
(e) Summary data
Data sheets, engineering drawings, etc., prepared by developer; mass balance analysis; accident and uncertainty analysis (this continues through a number of assessment stages) The same methods apply as in (b), but methods of production and technological forecasting are also relevant
Checklists, consultations with environmental agencies; alternatively, may be linked with l(a) through the use of matrices or through more elaborate representations of relationships such as networks Consultation with environmental agencies and voluntary organizations; use of data bank and retrieval systems Review of existing monitoring systems; special surveys using a variety of techniques (aerial photography, field sampling, etc.) Variety of available methods, ranging from simple forms of extrapolation to complex modelling studies; consultation with environmental agencies Mapping, overlay methods, summary sheets
Table 1. (contd) Tasks
3. Assessment of probable impact of developmeFlt (a) Assess magnitude of impact (in present and
future conditions) on: (i) air, water and Land (ii) receptors within the environment (b) Assess importance of impact by: (i) investigating response of affected parties (ii) aggregating individual environmental impacts 4. Compiiance with other environmental pians, policies arw’ cantrots Assess likely compliance of dcv~lopmcnt with existing and proposed controls 5. Ret&v ojaltgrnat~~e~ to the proposed
diffusion and resource utilization models, physical intrusion assessment ecological modelling, damage functions social surveys, agency consultation and public participation scaling and weighting systems, overlay methods, use of panel of experts
to be considered
(b) Describe project alternatives and assess their impacts 6. Preparation of non-technical summary qf the
Checklist (of types of alternatives to he reviewed), consultation and survey methods Same methods as in 1, 2, 3 above, combined with screening methods
Determine salient features of assessment and most effective means of presentation
investigation. Second, the chosen method should be sufficiently jkee from assessor bias enable different assessors using that method to make broadly the same assessment of any given impact. Often this will imply that the technical procedure af the method should be clearly specified, that it is reasonably explicit about the way in which incomplete or uncertain information is to be treated, that it identifies a consistent approach to the handling of value judgements, and that it provides for the presentation of results in a clear and unambiguous form. Third, the chosen method should ideally be economical in terms of costs and its requirements of data, investigative time, personnel and research facilities. In practice, one method will rarely score higher than its rivals according to all three criteria, Therefore the choice of method for any given task involves trade-offs between the different criteria and the balance between them will vary from one situation to another; a method which is best for a given task in one context may be quite inappropriate in another. It is for this reason that there must be some flexibility in selecting methods appropriate to the particuiar circumstances in which they are to be used. to
One of the early preoccupations in EIA was to try to ensure that the studies which were carried out identified at1 of the significant environmental impacts likely to result from a given development. This concern was justified to the extent that the coverage of environments impacts in project evaluation was previously considered to be very incomplete. The approach most frequently advocated for handling this problem was the
use of a matrix, listing both possible characteristics of the development and of the environment which might be affected by it, as a ‘check-system’ in identifying those aspects of the development and of the environment which might need to be investigated (see, for example, the matrix in Leopold et al. 1971).* The reason for constructing such matrices was sound but in practice a number of difficulties have arisen with the structure and use of certain matrices. First, there is the issue of the range of characteristics of the development and its environment which the matrix should cover. The characteristics of the proposed development are often described in terms of those associated ‘activities’ which may give rise to environmental impacts. These may be grouped according to the stage in the development at which they occur: land preparation, construction, operation or decommissioning. The activities which are listed may be restricted to those directly associated with the development itself or extended to include the activities of secondary developments which would be stimulated by the main development (e.g. infrastructure extensions, new housing development). Ideally the broader views should be taken, although this may be easier to achieve at the level of plan rather than project evaluation. Similarly, there are variations in the breadth of the environment covered in EIA matrices. Some matrices are limited to the characteristics of the natural and built environment whilst others also include elements of the social and economic environment. In part, this difference stems from a difference in view over whether EIA is a system for assessing all types of impact relevant to making a decision (in which case the EIA report becomes the definitive, comprehensive document for decision-making) or whether it is intended to provide a more systematic and comprehensive assessment of certain types of impacts (in which case, the EIA report is one of a number of
documentary inputs to the decision-making process). The narrower view is probably adopted more frequently but, in principle, either is acceptable-the choice often depending upon political and administrative preference-provided it is consistently applied. The characteristics of the natural and built environment can be defined according to the features of the receiving media (air, water, soil conditions, noise levels) and of the receptors (flora, fauna, structures) which reside in those media. Both receiving media and receptors may be affected indirectly (i.e. via impacts on other receiving media and receptors) as well as directly by a development. The matrix, however, is of limited value in identifying indirect impacts and there is a danger that any environmental impact assessment which relies too heavily on this identification tool will neglect the highorder impacts resulting from a development. Attempts have been made to extend matrices into more complex systems to assist in the identification of indirect impacts through pathway and network analysis (Sorenson 1970; Dee 1973; Environment Canada 1974; Holling 1978). However, these can greatly increase the size and complexity of the identification tool used.
* In the Leopold matrix ‘project actions’ are shown on the horizontal axis and are grouped into the following categories: A. Modification of regime; B. Land transformation and construction; C. Resource extraction; D. Processing; E. Land alteration; F. Resource renewal; G. Changes in traffic; H. Waste emplacement and treatment; I. Chemical treatment; J. Accidents; and so on. ‘Environmental characteristics and conditions’ are shown on the vertical axis of the matrix and are grouped into the following categories: A. Physical and chemical characteristics (earth, water, atmosphere and processes); B. Biological conditions (flora, fauna); C. Cultural factors; D. Ecological relationships; and so on.
In five widely quoted matrices developed during the 1970s the number of development characteristics ranged between 35 and 107 and the parameters of the environment between 24 and 88 (Sorenson 1970; Leopold 1971; Semeniuk 1976; Environmental Protection Service 1977; Clark 1981). In such cases there are a very large number of direct development-environment linkages that may need to be investigated: for example, 8800 in the Leopold matrix. In such a situation there is a danger that assessors will adopt a rather mechanical and indiscriminate approach to the assessment study, investigating too many of the cells in the matrix which relate to hypothetical direct impacts to the possible neglect of the more subtle, high-order impacts. The search for greater comprehensiveness in impact assessment has also increased the risk of double counting environmental impacts. The basic justification for using EIA in project appraisal is that certain types of development are likely to give rise to social costs which are not adequately taken into account in the developer’s own decision (Lee and Wood 1978). The EIA study should therefore include all social costs of an environmental nature but it should not include costs which the developer has already taken into account nor should it include the same environmental impact twice. This can easily arise when using detailed environmental matrices, for example: (a) A developer acquires agricultural land at the full market price and proposes to convert this to an industrial use. To include the loss of the agricultural land (or the value of the produce that would have been grown on that land) as a social cost would involve an element of doublecounting; (b) A development leads to a deterioration in air quality (measured by increases in concentration levels of certain pollutants) which causes a decline in property prices in the area. The inclusion of both the deterioration in air quality and the fall in property prices as measures of environmental impact also involves an element of double counting; Recently, a more discriminating approach to impact identification has begun to develop, largely as a reaction to the encyclopaedic EIA studies prepared during the early 1970s. Scoping procedures have been strengthened to help in the early identification of those activities or impacts associated with a development that need to be investigated. Screening procedures are increasingly used to avoid unnecessary further investigation once it has been established that a particular activity or impact is non-significant or that sufficient information has been obtained for the eventual decision to be taken. Therefore, identification is becoming a continuing activity which focuses investigation on a progressively narrower range of issues. For this purpose the assessor initially needs a matrix (or, conceivably, a simpler checklist supplemented by advice relating particularly to the identification of higher-order impacts) which is specific to the category of development and environment involved. Almost certainly the matrix will be modified subsequently in the light of the circumstances of the particular development being investigated and as more data become available. It thus becomes a much more adaptive tool assisting both in shaping the content of the study and in coordinating and summarizing the impact data collected at each stage of the investigation. 2. Data assembly The preparation of EIA studies involves the collection of considerable data from a variety of sources. Therefore the time and cost of data assembly is likely to be a sizable
proportion of the total time and cost spent in study preparation. A major criticism of many of the studies which have been carried out is that data collection has been insufficiently discriminating and that the data which are collected are often presented without sufficient analysis and interpretation appropriate to the decision to be reached (Council on Environmental Quality 1976). A more effective use of identification methods should result in a sharper definition of data requirements, and this should lead to better-directed searches of existing data sources and of special surveys for the additional data that may be needed. The forms of data analysis and interpretation which may be used are examined in later sections of this review. The data to be assembled are of two kinds: relating to the development and to the environment that would be affected. Data of the first kind should be available as a result of the design work undertaken for the proposed development, on such matters as land take and use, the physical form of the development, scale and processes of production, resource usage, size and composition of waste streams, treatment facilities and arrangements for waste disposal. However, certain kinds of problem may still be encountered, for example: (a) The design work may not be sufficiently advanced to enable waste and emission factors to be calculated during the early stages of the EIA study. Alternatively, emission factor data may be obtained from published sources (for example, the United States Environmental Protection Agency) but these need to be used with care because emission factors vary considerably between plants within the same industrial category. (b) The waste and emission factors recorded during plant operations diverge from the design standards built into the construction of plant, because of incorrect operation, inadequate maintenance or ageing of the plant. The discrepancies between the two sets of data should be small, in normal circumstances, but may be very substantial under accident conditions. A risk analysis should be undertaken as an integral part of the EIA study to determine the environmental significance of departures from normal operations (Clark 1981). (c) The characteristics of secondary developments likely to result from the proposed development will often be less well defined and data relating to these will be subject to greater margins of error. Assembling data on the characteristics of the environment is generally more complex. The objective is to define the base-line environmental conditions against which the impact of the development can be measured. The first step is to determine the existing conditions of the environment but, since this condition will change over time, it is more correct to define the base-line in terms of the likely future condition of the environment if the development were not to take place. In practice this is rarely attempted and to do so requires a good understanding of the ecological processes by which environmental conditions change over time (Holling 1978). In describing the existing characteristics of the environment it is customary to assembfe data on such elements as air, water and soil condition, geological structure, topography and landscape, climate and other variabfes which may affect the diffusion and degradation of wastes, the pattern of land use and the distribution and condition of potentiatly sensitive receptors in the area. Because of the large number of environmental parameters that could be investigated it is essential to identify the most important ones to be measured, either in the sense that they may be significantly affected by the development or that they are located on an important pathway through which such an effect may be transmitted. It is also necessary to determine the degree of
Environmental impact assessment: a review
detail (for example, the time and space intervals) in which measurements are to be sought. As previously mentioned, these requirements are likely to vary at different stages of the study. Having defined environmental data requirements, the next step is to establish the extent to which these can be met from existing sources. This task is sometimes more laborious than it should be because of the fragmentation of data sources. This situation could be improved by the extension of computerized environmental data banks, but these need to be carefully devised because the quality of data can deteriorate through its standardization and the evidence on the actual use made of such banking facilities is not particularly encouraging. At the local level environmental data are collected by a great variety of organizations-local authority departments, water authorities, universities, amenity societies-and useful work could be done in listing such sources, evaluating their quality, and possibly collating the data in a way which would make them more accessible for use in EIA (Wood et al. 1974). Any remaining deficiencies in data can be met only by special survey. Given the seasonal variation in the condition of most environments it is often necessary to extend certain surveys over a full year. Where this is the case, these need to be planned and put into operation at a sufficiently early stage in the programming of a new development proposal. A wide range of remote sensing and ground-based survey methods are available and a careful choice has to be made between them, based on the type of data required and the time and resource limitations within which the survey has to be conducted (Williams 1979). Once data relating to base-line environmental conditions have been collected it is natural, given their complexity, to consider the best way to summarize this information and to present it for further analysis and interpretation. One way in which this is sometimes summarized is as a single overall measure of the ecological value of individual sites (Ratcliffe 1977) but, explicitly or implicitly, this involves subjectively weighting the importance of different characteristics of the environment. The most popular way in which to present such data is by using some form of mapping technique. Here, also, problems arise in the choice of parameters to be mapped and their numerical intervals since value judgements are implicit in the selection process. Overlay mapping techniques are helpful in showing the spatial relationship between different environmental parameters (and, subsequently, the spatial distribution of a development’s impact on the environment). In some studies this technique is extended by varying the colour and tonal intensity on the overlay to reflect the significance of the parameter or of the impact of the development upon it (McHarg 1969; Steinitz 1969). In these circumstances, an element of subjective judgement is similarly implicit in the presentation technique used. Simplification and the use of value judgements are probably unavoidable in the later stages of EIA where it is necessary to evaluate the importance of a development’s impact and to present this in a form suitable for consultation and decision-making. However, this is probably less necessary in the much earlier stage of data assembly. 3. Predictive methods Predictive methods are used to determine the magnitude of the expected impacts of a development whilst evaluative methods are intended to assess the significance of those impacts. A distinction is made between the two types of methods because the latter more typically involve the use of value judgements. In practice, both types of analysis used are often less than satisfactory. In a number of studies the size of impacts is not indicated, except in qualitative terms, and, where magnitudes are stated, the method of
analysis used to determine them may not be recorded. The distinction between the magnitude and significance of an impact is often blurred and it is common to rely on an expert’s judgement of whether an impact will be large or important without disclosing the form of analysis he has used to reach that judgement (Environmental Resources 1981). Perhaps, then, the single most important improvement that should be sought in EIA practice is in requiring the presentation of clearer estimates of the magnitude and significance of impacts and of the methods of analysis used to determine them. Where formalized, numerical prediction methods are used they are most commonly restricted to prediction of first-order, direct impacts (Canter 1977; Golden 1979; Lee and Wood 1980b; Rau and Wooten 1980). The main methods used can be grouped into the following categories : (a) models to predict changes in ground-level pollutant concentrations likely to result from emissions through a single chimney or from multiple sources; (b) models to predict changes in water quality in rivers, estuaries, lakes and coastal waters likely to result from single or multiple aqueous discharges into the system; (c) hydraulic models of surface waters and aquifers to predict effects of developments on tidal levels, sediment transport and siltation, ground-water flow, etc.; (d) models to predict changes in ambient noise levels likely to result from transport or industrial development schemes; (e) visibility models to represent the physical form of a proposed development in the landscape in order to determine the extent and type of visual intrusion which may result; (f) survey methods to determine the loss of natural habitats, etc., which would directly result from a proposed development. The techniques available within each of these categories vary greatly in their complexity, data requirements and the form and accuracy of their findings. For example, changes in air pollution concentration levels may be predicted using simple ‘roll-back’ models, based on the crude assumption that concentration levels increase in direct proportion to emissions, Gaussian and K-theory dispersion models of varying levels of complexity, wind tunnel techniques, and empirical models based upon regression analysis of historical data. The criteria to be used in selecting between these for use in any particular situation have already been discussed (see Methods of assessment). However, whichever method is used can only predict the likely magnitude of impact with a margin for error and it is important that this margin should be recorded so that it can be taken into account in the interpretation of the results of the EIA study. Higher-order, indirect impacts are much less frequently predicted by using numerical models. This is partly due to weaknesses in procedures for identifying potentially important higher-order impacts but it is also due to insufficient understanding of the quantitative nature of many of these higher-order relationships. For example, in order to predict the consequential effect of changes in the quality of receiving media on flora, fauna and structures resident in those media, fairly clear knowledge of the relevant dose-response relationships is needed. For the most part this knowledge is very incomplete (Saunders 1976). This means that the description of higher-order impacts will often be restricted to a summary of the type and number of species exposed to damage with, where possible, an indication of the order of magnitude of the damage which may be caused. At the same time knowledge of higher-order impacts is increasing and, as this happens, it is important that it is made available for use in EIA. Where numerical models to predict higher-order impacts have been used in EIA studies they
Environmental impact assessment: a review
have mainly been of the following types: (a) models for predicting the effect of emissions on soils and water quality; (b) pathway analysis to predict the higher-order impacts of persistent pollutants in air, water and soils; (c) eutrophication models to predict the effects of changes in nutrient and heat levels on the productivity of different types of waters; (d) population models to predict the effects of changes in water quality on the size of particular fish and bird populations; (e) recreation models to predict the effects of water quality changes on the level of recreational benefits; (f) noise models to predict the effects of sound changes on the extent of annoyance experienced in a community; (g) vibration models to predict the effects of sound changes on the level of damage to buildings. The predictions derived from such models as these are generally subject to greater margins of error than those which apply to the previously discussed models. It is therefore all the more important that these margins of error are also recorded to avoid any misleading impression of predictive accuracy. 4. Evaluation methods Evaluation is concerned with determining the significance of individual environmental impacts and/or the aggregate significance of all environmental impacts relative to the economic and social effects of a development. The role of evaluation methods in EIA is disputed, largely because of the place that value judgements occupy within them. Broadly speaking there are two extreme viewpoints (Lee 1982): (a) Because evaluation involves value judgements, and technical specialists in environmental impact assessment have no special expertise to represent the value judgements of the community experiencing these impacts, the EIA report should be limited to a statement of the likely magnitudes of the individual environmental impacts associated with a development. The competent authority should, according to this view, be left free to determine the importance of particular impacts and weight them accordingly in reaching its decision. (b) The competent authority expects to be supplied both with the factual particulars of the case and with as objective advice as possible on the decision to be reached. To do this, it is argued, those carrying out the EIA study should attempt to derive a measure of the environmental significance of the development as a whole. There are a number of difficulties with both of these viewpoints. Where a development is likely to result in a large number of different impacts, both the general public and those responsible for authorizing the decision may have difficulty in handling the large number of items of impact which have been measured and may feel compelled to base their judgement on only a small number of these, to the somewhat arbitrary exclusion of the rest. More fundamentally, measures of the magnitude of individual impacts (e.g. changes in concentration levels of particular pollutants) will not be meaningful to most laymen, who will be unaware of the consequences which may result from different levels of impact. Therefore, disaggregated data relating to the size of individual impacts is of limited direct use for purposes of public consultation and decision-making.
A number of EIA studies have adopted this first approach, though sometimes this has been supplemented by ‘advice’ on the overall environmental significance of a development without the procedure and criteria by which that advice has been determined being stated. However, a number of the early integrated methodologies did attempt to systematize the evaluation procedure by developing some form of scaling and weighting system. For example: 1. The method developed by Leopold involves recording both the magnitude and significance of each impact on a scale l-10, but no attempt is made to aggregate impacts across categories (Leopold et al. 1971). 2. The Environmental Evaluation System, developed for the Battelle Institute, uses value functions to normalize each impact magnitude on a common scale O-l (Fig. 1). Each scaled magnitude is then multiplied by a weight which is intended to reflect the relative importance of the type of impact involved. Finally, the measure of significance of the total environmental impact of a development is obtained by summing the resulting scores for all impacts associated with a development (Dee et al. 1973). 3. The WRAM System, developed for the US Army Corps of Engineers, is also based upon scaling and weighting, but involves pair-wise comparisons in deriving scale and weight values for use in comparing alternative development schemes (Solomon et al. 1977). 4. Social cost-benefit analysis methods involve expressing the value of environmental impacts in monetary units and incorporating the monetary measures of the environmental impacts in the calculation of the net present value of the proposed development (Cooper 1981). 5. Overlay methods record the location and importance of individual impacts on separate transparencies using a standardized system of shading or colour, tonal
$ Ti + t E
i z al 050? G= Q z
I 4 Dissolved
Figure 1. Example of a value function as a measure of water quality.
intensity, etc. The aggregate importance of all impacts, and the spatial distribution of these, is shown by overlaying the transparencies or by a computerized equivalent of the same process (McHarg 1969; Steinitz et a/. 1969). These types of methods have been criticized, particularly where they are used to obtain a single, aggregated measure of the total environmental impact of a development, and for this reason most of them do not appear to be widely used in practice (Environmental Resources 1981). The main criticisms that have been made are the following: weakness in scaling: because of deficiencies in dose-response data and in measures of social response to many kinds of environmental impact, scaling can often be very subjective and a major source of bias; weakness in weighting: the methods by which weights are determined are often insufficiently systematic and explicit, and can be a further source of bias; professional theft of decision-making: scaling and weighting systems may impart a false degree of sophistication, objectivity and precision to professional advice which may discourage decision-makers from reaching their own conclusion.
There is a considerable need to improve evaluation practice in EIA. Rather than base the approach on the two extremes already described, the evaluation procedure used should adopt an intermediate approach which aims to identify the key impacts and trade-offs which are of central importance to making the decision on a proposed development and to provide decision-makers with intelligible information on those impacts and trade-offs. More particularly: 1. Where scaling and weighting procedures are used, the method which has been followed should be explained and the impact magnitudes upon which it has been based should be stated. 2. Any elements of uncertainty in the estimates of impact magnitude should also be indicated, showing how these have been handled in the analysis (e.g. by probability or sensitivity analysis). 3. The values upon which scales and weights are based should not be determined solely according to the assessor’s own value judgements, but also upon community views obtained through consultation, sample survey, etc. Where different value systems are identified, the sensitivity of the eventual decision to the choice between these different sets of values should be tested. 4. The sections of the community which will be affected by the different impacts should also be recorded to provide decision-makers with information on the likely distributional consequences of each development.
Up to this point the review has been concerned with methods for undertaking the technical work in conducting an EIA study. Unavoidably, given the complexity of the tasks involved, many of these methods are technically sophisticated and can be handled satisfactorily only by specialists. However, another distinctive feature of EIA is the ‘open-ness’ of the system through provisions for consultation and public participation in preparing and testing the study and for publication of its findings. For such purposes it is necessary to devise effective methods of presenting information in a form which is
appropriate to the background and needs of those who are invited to comment or reach a decision upon the EIA study. The task is not an easy one: (a) The subject matter of major EIA studies is often broad in its coverage and inherently complex. Any simplification of the material runs the risk of distorting the findings or presenting them in too superficial a form. (b) Those to whom the report of an EIA study needs to communicate are themselves varied in their interests and educational and professional background. They include members of the general public living in the vicinity of the proposed development, representatives of environmental interest groups, technical staff attached to the various official environmental organizations involved in the consultation exercise and community representatives forming the authority which will make the final decision about the proposed development. (c) Those who are most skilled in conducting the technical investigations involved in EIA and writing technical reports based on these are not necessarily skilled in writing reports for a more general readership. Studies reviewing the early experience in EIA indicate that communication has been considerably less effective than originally envisaged. In the United States, EISs were often too long, written in too technical and complex language, and failed to summarize the key issues that were central to reaching a decision (Council on Environmental Quality 1976). At the same time as many failed to meet the requirements of a general readership, many also failed to provide the technically supportive evidence sought by specialist environmental organizations. More attention is now being given to correcting these deficiencies. In the United States, for example, limits are now imposed on the maximum size of the EIS, key issues are presented in a non-t~hnic~ summary and technical detail is transferred to appendices. CEQ regulations now indicate that ‘environmental impact statements should be written in plain language and may use appropriate graphics so that they may be understood by decision-makers and the public, Agencies should employ writers of clear prose or editors to write, review or edit statements . . .’ (Council on Environmental Quality 1978). Elsewhere, models, exhibitions, films and different kinds of simple documentation are being used to supplement the EIA report and help to communicate its principal findings.
Conclusions The growth in the use of EIA since 1970 has been very considerable and is likely to be followed, during the 198Os,by consolidation in two main directions: the extension of EIA to the planning and approval of actions which are broader in scope than individual development projects, and further improvements in the quality and cost-effectiveness of EIA studies and the practical use made of these for decision-making purposes. The authorization of individual projects occurs at a relatively late stage in the planning of new development. By this point the alternative courses of action which may be fohowed are usually fairly limited. Ideally, in a fulty developed system, an EIA should be prepared at each major stage in policy and plan formation for each major economic sector (e.g. transport, energy) and each land-use planning area. Taken together, they would form a tiered EIA system parallei to, and integrated at each key stage into, the sectoral and land-use planning system of each country. At the high tier levels, only broad, strategic assessments of major policy and planning alternatives
would be carried out whilst at the lowest tier levels EIA would consist of much more detailed, project and site-specific assessments as at present. During the initial period of expansion in the use of EIA, the quality of the EIA studies produced has been highly variable. This is not particularly surprising given the deficiencies in the less formal arrangements for environmental evaluation which previously existed. Nevertheless, a further improvement in the general level of the quality of these studies must be a high priority. The more immediate prospects for improvement are unlikely to lie in the development of entirely new methodological approaches, particularly of the kind that were developed during the early 1970s and which appear to have had a limited impact on general practice. More progress is likely to be made by the careful selection and use of assessment methods already available, chosen according to their appropriateness to the particular task involved, the objectivity of the assessment they provide, their cost-effectiveness and their usefulness for decision-making. On the basis of the above review, there is scope for improvement in EIA practice in the following ways: (a) Use of simple matrices or checklists related to specific types of development or environment, which are supplemented by advice notes on the identification of higher-order impacts and double-counting problems-matrices should be adapted by those carrying out the EIA study at successive stages in the development of the study. (b) More widespread use of scoping and screening procedures to ensure that the resources invested in an EIA study are used to investigate the most important and complex impacts. (c) Collection of data relating to probable deviations from the designed operating conditions for a development, and the preparation of a risk analysis based on these data to determine the likely environmental significance of such deviations. (d) Preparation of guides to existing environmental data sources and/or the establishment of data banks to improve accessibility to existing environmental data for those preparing EIA studies. (e) Preparation of guides on the choice of survey methods to obtain the additional environmental data needed to complete inventories of base-line environmental conditions. (f) Greater emphasis within EIA studies on those stages of analysis which are concerned with the prediction and evaluation of impacts and, in the EIA reports which are published, a more explicit account of the methods of prediction and evaluation which have been used. (g) Preparation of guides on the choice of models that could be used for the prediction of first-order impacts. (h) Development and use of improved methods of analysis for the prediction of higherorder impacts. (i) Use of suitable methods to record the likely degree of accuracy of the predictions made of impact magnitudes and treatment of uncertainty in the final presentation of the study’s findings. (j) Preparation of evaluation procedures which assist decision-makers by adopting an easily understood, systematic approach to the determination of key impacts and of the main trade-offs involved in choosing between alternative development proposals, without attempting to produce an aggregate measure of the total environmental impacts of those developments. (k) Greater use of social survey techniques in determining the relative importance
which communities attach to different types of environmental impact; of sensitivity analysis to determine how the decision on a proposed development might be influenced by changes in the weights attached to particular impacts; and of analysis to show the likely distribution of the impacts of a development between different sections of the community. (1) Greater emphasis on clear presentation of the findings of EIA studies in a form which is best suited to the requirements of those who are to be consulted for their opinions. Many of these improvements can be secured in the short term, although others will take a longer period to accomplish. One of the first priorities is to initiate systematic, detailed reviews of existing assessment methods, preferably organized according to economic sector or class of project, in which both technical specialists and potential users of EIA studies are involved. They should include simple methods of analysis as well as more sophisticated and complex modelling techniques. Such reviews should provide the information needed to prepare manuals or guidelines to assist those engaged in the preparation of EIA studies within the sectoral and project categories to which they relate. The practical use of these manuals and guidelines should be monitored and they should be periodically revised in the light of the experience gained. In parallel to this, short training programmes in the use of these manuals and guidelines should be planned, both for technical specialists who need to appreciate the overall EIA context into which their particular work will fit, and for those engaged in the more interdisciplinary work of managing the EIA study as a whole and integrating the contributions made by technical specialists within it. In the longer term, improvements in EIA practice will depend upon the future pattern of environmental survey and research activities. In particular, improvements should be sought through encouraging the following: 1. Review of existing environmental monitoring systems and other periodical survey activities to determine their most appropriate contribution to the needs of EIA for policy, plan and project evaluation. 2. Review of existing arrangements for environmental data collection, storage and retrieval and assessment of whether these might be made more effective for use in preparing EIA studies. 3. Research to improve understanding in specific areas of project impact assessment (e.g. prediction of changes over time in base-line environmental conditions, predicting higher-order environmental impacts, scaling impact measures according to their environmental significance, and social assessment of the relative values placed upon different kinds of environmental impact). 4. Research to improve understanding in specific areas of policy and plan assessment (e.g. determination of waste and resource use coefficients for use in strategic-level studies, further development of multi-point pollutant diffusion models, and integrated use of economic and environmental forecasting techniques in policy and planning studies). A substantial improvement in the quality and effectiveness of EIA could be achieved by such measures as these. This would raise the general level of confidence in its practical usefulness and make it easier to extend its application into the earlier stages of policy and plan formation where its hold is relatively weak at the present.
References Canter, L. (1977) Environmental impact assessment. New York: McGraw-Hill, Clark, B. D., Bisset, R. and Wathern, P. (1980) Environmental impact assessment: a bibliography with abstracts. London: Mansell. Clark, B. D., Chapman, K., Bisset, R., Wathern, P. and Barrett, M. (1981) A manual for the assessment of mujor development proposals, London : HMSO. Cook, P. L. (1979) Costs of environmental impact statements and the benefits they yield in improvements to projects. In Seminar on environmental impact assessment. Geneva: Economic Commission for Europe (restricted). Cooper, C. (1981) Economic evaluation and the environment. London: Hodder and Stoughton. Council on Environmental Quality (1973) Preparation of environmental impact statements: guidelines. Federal Register 38, No. 147, 20550. Washington, DC: USGPO. Council on Environmental Quality (1976) Environmental impact statements: an analysis of six years’ experience by seventy federal agencies. Washington, DC: CEQ. Council on Environmental Quality (1978) National Environmental Policy Act: proposed regulations for implementing procedural provisions. Federal Register 43, No. 112, 25230. Washington, DC: USGPO. Council on Environmental Quality (1980) Environmental qualityP1980. Washington, DC: USGPO. Dean, F. E. (1979) The use of environmental impact analysis by the British gas industry. In Symposium on practices in environmental impact assessment. Brussels: Commission of the European Communities (mimeo). Dee, N., Drobny, N. L., Baker, J. K., Duke, K. M. and Fahringer, D. C. (1973) Planning methodology for water quality management: environmental evaluation system. Columbus, OH : Battelle Memorial Institute. De Souza, S. P. (1980) Environmental impact assessment: an international review with particular reference to developing countries. MSc dissertation, University of Manchester (mimeo). Economic Commission for Europe (1979) Report of the Seminar on Environmental Zmpact Assessment. Geneva: ECE (restricted). Environment Canada (1974) An environmental assessment of Nanaimo Port alternatives. Ottawa: Environment Canada. Environmental Protection Service (1977) A guide for environmental screening. Ottawa: Department of Fisheries and Environment. Environmental Resources (198 1) Environmental impact assessment: studies on methodologies, scoping and guide-lines. London: ERL. Golden, J., Ouellette, R. P., Saari, S. and Cheremisinoff, P. N. (1979) Enuironmental impact data book. Ann Arbor, MI: Ann Arbor Science. Goldsmith, B. J. (1974) Delays in initiating construction of energyfacilities in the United States due to environmental review procedures. Paris: OECD. Holling, C. S. (ed.) (1978) Adaptive environmental assessment and management. Chichester: Wiley. House of Commons (1981) Environmental assessment of projects. London: HMSO, First Standing Committee on European Community Documents, Parliamentary Debates Official Report, 9 June. Hurtubise, F. G. and Wolf, P. G. (1980) Federal environmental assessment and review process in Canada. Industry and Environment (special issue), No. 1, 3-5. Jones, M. G. (1980) Developing an EIA process for the Netherlands. Environmental Impact Assessment Review 1, 167-80. Kennedy, W. V. (1980) Environmental impact assessment in the Federal Republic of Germany. Environmental
Lee, N. (1982) The future Environmental
Lee, N. and Wood, the European Lee, N. and Wood, Community.
14, 7 l-90.
C. M. (1978) The assessment of environmental impacts in project appraisal in Communities. Journal of Common Market Studies 16, 189-210. C. M. (1980a) Environmental impact assessment in the European Economic Environmental
Lee, N. and Wood, C. M. (1980b) Methods of environmental impact assessment for use in project appraisal and physical planning. Manchester: University of Manchester, Department of Town and Country Planning, Paper No. 7. Leopold, L. B., Clarke, F. E., Hanshaw, B. B. and Balsley, J. R. (1971) A procedurefor evaluating environmental impact. Washington, DC: US Geological Survey. Liroff, R. A. (1981) NEPA litigation in the 1970s: a deluge or a dribble? Natural Resources Journal 21, 315-330. McHarg, I. L. (1969) Design with nature. New York: Natural History Press. Ministere de 1’Environnement (1980) Les etudes d’impact: 30 mois d’application. Paris: Delegation a la Qualite de la Vie. Ministry of Health and Environmental Protection (1979) Summary report: recommendations on environmental impact assessment on the basis of trial runs and complementary research. Leidschendam: MHEP. Ministry of Health and Environmental Protection (1980) Governmental standpoint on enoironmental impact assessment. Leidschendam: MHEP. Munn, R. E. (ed.) (1979) Environmental impact assessment. Toronto: SCOPE, SCOPE Report No. 5, 2nd ed. Ratcliffe, D. A. (1977) The conservation of important wildlife areas in Great Britain. Bulletin of the British Ecological Society 8, 5-l 1. Rau, J. G. and Wooten, D. C. (eds) (1980) Environmental impact analysis handbook. New York: McGraw-Hill. Saunders, P. J. W. (1976) The estimation of pollution damage. Manchester: Manchester University Press. Semeniuk, R. A. (1976) Environmental impact ecaluation: an instrument of planning and design. Ottawa: Department of Public Works. Solomon, R. C., Colbert, B. K., Hansen, J. W., Richardson, S. E., Canter, L. W. and Vlachos, E. C. (1977) WRAM: impact assessment an? alternatioe evaluation. Vicksburg, MS: US Army Corps of Engineers. Sorensen, J. (1970) A framework for ident$cation and control of resource degradation and conflict in the multiple use of the coastal zone. Berkeley, CA: University of California. Steinitz, C., Murray, T., Sinton, D. and Way, D. (1969) A comparative study of resource analysis methods. Cambridge, MA: Graduate School of Design, Harvard University. UNEP (1980) Guidelines for assessing industrial environmental impact and environmental criteria for the siting of industry. Paris: UNEP Industry and Environment Office. Weiner, K. S. (1980) NEPA is good business. Industry and Environment (special issue), No. 1, 16-19. Williams, L. (1979) An evaluation of ecological survey techniques applicable to environmental impact assessment. MSc dissertation, University of Manchester (mimeo). Wood, C. M. (1982) The impact of the European Commission’s directive on environmental planning in the UK. Planning Outlook 24, 92298. Wood, C. M., Lee, N., Luker, J. A. and Saunders, P. J. W. (1974) The geography of pollution. Manchester: Manchester University Press, (Revised manuscript received 8 June 1982)