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Element 2 - Environmental Risk Evaluation.

Overall Aims

On completion of this unit, candidates will have knowledge and understanding of:

qualitative and quantitative environmental risk assessment techniques, including cost benefit analysis, environmental impact assessment, environmental modelling, life cycle analysis;

assessment of environmental toxicity, including the principles of ecotoxicology.

Specific intended learning outcomes:

The intended learning outcomes are that candidates will be able to:

evaluate risks to the environment arising from workplace activities and substances released to the environment;

identify when an environmental assessment is required and understand the processes underlying preparation and submission of a formal Environmental Statement.

Hours of tuition and private study:

9 hours of tuition;

3 hours of private study.

Relevant statutory provisions:

Town and Country Planning (Environmental Impact Assessment)(England and Wales) Regulations 1999.

Environmental Assessment of Plans and Programmes Regulations 2004. Control of Major Accident Hazards Regulations 1999. Control of Substances Hazardous to Health Regulations 2002.

1.0 Introduction.

Environmental risks are approached by identifying the most suitable control strategy and then trying to control the risks at least cost. We call this 'cost benefit analysis' where there is a level of financial account in the control of environmental risk.

1.1 Cost Benefit Analysis as Applied to Environmental Risk.

Cost benefit analysis is advocated in UK legislation in the form of control systems which are the best available technique not entailing excessive cost (BATNEEC).

Costs - These are incurred by industry, government and society.

Benefits these are defined as reductions in risks to the health and the environment arising from regulation.

The environmental management system ISO 14001 states that

When considering their technological options, an organisation may consider the use of Best Available Technology where economically viable, cost-effective and judged appropriate. The reference to the financial requirements of the organisation is not intended to imply that organisations are obliged to use cost-accounting methodologies.

Cost-benefit analysis is mainly - but not exclusively - used to assess the value for money of very large private and public sector projects. This is because as well as those can be expressed purely in monetary terms, such projects tend to include costs and benefits that are less amenable to being so expressed (e.g. environmental damage). The accuracy of the outcome of a cost-benefit analysis is dependent on how accurately costs and benefits have been estimated. All stakeholders should play a part in the weighting of factors.

1.2 Techniques for Environmental Valuation.

In order to assess the economic value of environmental good, methods have been defined to assess this. These methods are devised to identify an individuals willingness to pay for a benefit and their willingness to accept compensation for tolerating a cost of foregoing a benefit. The methods can be based on two approaches: revealed preferences and stated preferences.

Revealed preferences

Revealed preference approaches include

Dose-response function, market values, hedonic markets, travel cost/discrete choice, wage risk and property.

Stated preferences

These include Contingent valuation and conjoint analysis approaches.

Travel Cost Method

The travel cost method is used to estimate economic use values associated with ecosystems or sites that are used for recreation. The method can be used to estimate the economic benefits or costs resulting from:

changes in access costs for a recreational site; elimination of an existing recreational site; addition of a new recreational site; changes in environmental quality at a recreational site.

The basic premise of the travel cost method is that the time and travel cost expenses that people incur to visit a site represent the price of access to the site. Thus, peoples willingness to pay to visit the site can be estimated based on the number of trips that they make at different travel costs. This is analogous to estimating peoples willingness to pay for a marketed good based on the quantity demanded at different prices.

Hedonic Pricing Method

The hedonic pricing method is used to estimate economic values for ecosystem or environmental services that directly affect market prices. It is most commonly applied to variations in property prices that reflect the value of local environmental attributes.

It can be used to estimate economic benefits or costs associated with:

environmental quality, including air pollution, water pollution, or noise; environmental amenities, such as aesthetic views or proximity to recreational sites.

The basic premise of the hedonic pricing method is that the price of a marketed good is related to its characteristics, or the services it provides. The hedonic pricing method is most often used to value environmental amenities that affect the price of residential properties. e.g. the presence of woodland which may enhance the value of a property.

Contingent Valuation

This is both an economic tool and community analysis tool. It is considered most useful during the strategy development phase, where it is often used in deciding how much to charge for a good or service. It is a part of a family of tools that addresses issues of benefits not traded in markets; for example, environmental quality and historic cities. The approach is based on interviews with a representative sample group in an area. The interview consists of three stages which include:

a detailed description of the goods being valued and the hypothetical circumstance under which it is made available to the respondent;

questions which bring out the willingness to pay for the good to be provided; questions about the respondent characteristics (for example: age, income), their

preference relevant to the good(s) being valued, and their use of the good(s); this information is then generalised for a representative group of people.

Contingent Ranking (or Conjoint Analysis)

This ranks alternatives, with one of the alternatives pinned to a money price, i.e. would you be prepared to pay more or less for something than X. Conjoint analysis uses profiles which are bundles of attributes, for example, when evaluating a preference for paper, respondents are given several profile cards each of which contains a unique paper product composed of different textures, colours, thickness, weight and price and they are asked for their preference.

1.3 Dose Response/Production Function.

Dose-response functions measure the relationship between exposure to pollution as a cause and specific outcomes as an effect. They refer to damages/production losses incurred in the current year, regardless of when the pollution occurs. Such functions are available for the impacts on human health, building materials and crops caused by a range of pollutants such as primary and secondary (i.e. nitrates, sulphates) particles, ozone, CO, SO2, NOx, Benzene.

Replacement Cost

The cost of replacement of an asset may be used as another cost factor. However, replacement value is not always representative of actual costs incurred, for example by loss

of production as a result of product failure.

CBA and Sustainability

The accepted definition of sustainability is the concept of meeting the needs of the present without compromising the ability of future generations to meet their own needs. Short-term gain has to be calculated over the needs of future generations and the rate at which society values the present with respect to the future is referred to as the `social time preference`.

CBA and Stakeholder Analysis

The costs and benefits for individual stakeholders may be very different. With the use of stakeholder analysis, key players, winners and losers can be identified. The behaviour of these individuals can then be anticipated and planned for.

1.4 Sensitivity and Scenario Analysis.

Sensitivity analysis is the study of how the variation in the output of a model (numerical or otherwise) can be apportioned, qualitatively or quantitatively, to different sources of variation. Sensitivity analysis is used to test the vulnerability of options to unavoidable future uncertainties. The substitution of different values for a variable shows by how much it would have to fall (if a benefit) or rise (if a cost) to make it not worth pursuing an option. Sensitivity analysis can be undertaken with scenario analysis.

Scenario analysis is a process of analysing possible future events by considering alternative possible outcomes (scenarios). The analysis is designed to allow improved decision-making by allowing more complete consideration of outcomes and their implications. Scenarios are useful to show how options may be affected by future uncertainty.

Cost Benefit Analysis Conclusion

The accuracy of the outcome of a cost-benefit analysis is dependent on how accurately costs and benefits have been estimated. It can be used effectively to inform the decision- making process but the most economically efficient option does not necessarily mean it is the one most socially desirable or sustainable.

2.0 Environmental Impact Assessment (EIA).

Introduction

There has been a growth in interest in environmental issues such as sustainability and the better management of development in harmony with the environment.

The present environmental impact assessment regime in England and Wales and Scotland is based on the 1985 European Council Directive 85/337/EEC on the Assessment of the Effects of Certain Public and Private Projects on the Environment (the EIA Directive) (It is interesting to note that EIA legislation was introduced in the USA in the 1970s).

Directive 97/11/EC amends the original Directive 85/337/EEC on 'The assessment of the effects of certain public and private projects on the environment', which came into effect in July 1988 Since its introduction in the UK in 1988, it has been a major growth area for planning practice. It is therefore surprising that the introduction of EIA met with strong resistance.

It was amended and extended in 1997. Many developers saw it as yet another costly and time-consuming constraint on development, and central government was also unenthusiastic.

In England and Wales the Directive is implemented by the Town and Country Planning (Environmental Impact Assessment) ( England and Wales ) Regulations 1999. These principal regulations were made by the then Secretary of the State for the Environment, Transport and the Regions using powers conferred on him by the Town and Country Planning Act 1990. Other regulations covering specific types of development include: The Environmental Impact Assessment (uncultivated land and Semi-natural Areas) ( England ) Regulations 2001.

In Northern Ireland, the Department of the Environment made The Planning (Environmental Impact Assessment) Regulations ( Northern Ireland ) 1999, and other specific regulations.

In Scotland the Directive is implemented by regulations made by the Scottish Ministers, including the Environmental Impact Assessment (Scotland) Regulations 1999 and other more specific regulations , for example the Environmental Impact Assessment (Forest) (Scotland) Regulations 1999.

2.1 What is an Environmental Impact Assessment (EIA)?.

There are numerous definitions of Environmental Impact Assessment. The term describes an important procedure for ensuring that the likely effects of new development on the environment are fully understood and taken into account before the development is allowed to go ahead. The process was formerly referred to in the UK as `environmental assessment' (EA).

The EIA process is a systematic process that examines the environmental consequences of development actions in advance. The process is a means of drawing together an assessment of a projects likely significant environmental effects. This helps ensure that the importance of the predicted effects, and the scope for reducing them, are properly understood by the public and the relevant competent authority before it makes its decision.

Planners have traditionally assessed the impacts of developments on the environment, but invariably not in the systematic, holistic and multi-disciplinary way required by EIA. Environmental impact assessment enables environmental factors to be given due weight, along with economic or social factors, when planning applications are being considered. It helps to promote a sustainable pattern of physical development and land and property use in cities, towns and the countryside. If properly carried out, it benefits all those involved in the planning process.

2.2 Who is Involved in an EIA?.

The Developer

From the developer's point of view, the preparation of an environmental statement in parallel with project design provides a useful framework within which environmental considerations and design development can interact. Environmental analysis may indicate ways in which the project can be modified to avoid possible adverse effects, for example through considering more environmentally friendly alternatives. Taking these steps is likely to make the formal planning approval stages run more smoothly.

The Planning Authority

For the planning authority and other public bodies with environmental responsibilities, environmental impact assessment provides a basis for better decision making. More thorough analysis of the implications of a new project before a planning application is made, and the provision of more comprehensive information with the application, should enable authorities to make swifter decisions. While the responsibility for compiling the environmental statement rests with the developer, it is expected that the developer will consult those with relevant information, and the Regulations specifically require that public authorities which have information in their possession which is relevant to the preparation of the environmental statement should make it available to the developer.

The General Public

The general public's interest in a major project is often expressed as concern about the possibility of unknown or unforeseen effects. By providing a full analysis of a project's effects, an environmental statement can help to allay fears created by lack of information. At the same time, early engagement with the public when plans are still fluid can enable developers to make adjustments which will help to secure a smoother passage for the proposed development and result in a better environmental outcome. The environmental statement can also help to inform the public on the substantive issues which the local planning authority will have to consider in reaching a decision. It is a requirement of the Regulations that the environmental statement must include a description of the project and its likely effects together with a summary in non-technical language. One of the aims of a good environmental statement should be to enable readers to understand for themselves how its conclusions have been reached, and to form their own judgements on the significance of the environmental issues raised by the project.

2.3 Identification of Projects Requiring Formal Environmental Assessment.

The regulations prohibit the Local Planning Authority (LPA) from granting planning consent unless the requirements of the regulations have been complied with. The first stage in the process requires the Local Planning Authority to determine whether or not the proposed development requires an Environmental Impact Assessment.

If an applicant is unsure whether or not an Environmental Impact Assessment is required, a draft plan can be submitted showing the location of the proposed development and a description of the proposal and likely environmental effects.

The Local Planning Authority will consider in which category, if either, the proposal falls, or whether the proposal is outside the scope of the EIA regime.

The Regulations apply to two separate lists of projects, Schedule 1 and Schedule 2:

i. 'Schedule 1 projects', for which EIA is required in every case;

ii. 'Schedule 2 projects', for which EIA is required only if the particular project in question is judged likely to give rise to significant environmental effects.

Schedule 1 Projects

For Schedule 1 projects, whether or not a particular project falls within the scope of the Regulations will normally be clear: several of the definitions of Schedule 1 projects incorporate an indication of scale, in the form of a quantified threshold based on throughput, size etc., which clearly identifies the projects requiring EIA.

Although installations dealing with smaller quantities may not have the potential to cause significant environmental impact, these would not automatically come under Schedule 1 but may fall under Schedule 2 due to their size, nature or location.

Where there is any doubt about a project's inclusion in Schedule 1, the procedures described below can be used to obtain an opinion from the planning authority or a direction from the Secretary of State (or, in Wales, the National Assembly for Wales).

Crude oil refineries (>500 t d-1)

Thermal power stations (>300 MW)

Nuclear power stations

Nuclear fuel processing and production installations

Iron and Steel Works

Asbestos extraction and processing

Integrated chemical installations

Long distance railway lines

Airport runways >2,100 m long

Motorways and express roads

New roads >4 lanes, or 2 lanes >10 km long

Inland waterways, ports and piers to take vessels >1350 t

Waste incinerators for, and landfill of, hazardous waste

Waste incinerators of non-hazardous waste >100 t d-1

Groundwater abstraction >10 x 10 6 m3Y-1

Movement of water >10x106m3y-1

Wastewater treatment works serving >150,000 people

Petroleum (500,000 m3d-1)

Dams >10X106m3 storage capacity

Water, gas, oil and chemical pipelines >800mm diameter and >40 km long

Intensive farming units (>85,000 broilers, 60,000 hens, 3,000 pigs or 900 sows)

Timber pulp and paper plants >200 td-1

Quarries and open cast mining >25 ha, or peat extraction >150 ha

Table 1. Developments that require an EIA under Schedule 1

Schedule 2 Projects

For the much longer list of Schedule 2 projects, the issue turns on the likelihood of 'significantenvironmental effects'. For the different types of project, the 1999 Regulations introduced a system of thresholds and criteria as a method of discounting development which is not likely to have significant effects on the environment. For development where the applicable threshold or criterion is not exceeded or met, EIA is not normally required.

However, even where the threshold or criterion is not met or exceeded, EIA may be required if the proposed development is in, or partly in, a 'sensitive area'.

In exceptional circumstances the Secretary of State (or, in Wales, the National Assembly for Wales) may exercise his power under the Regulations to direct that a particular type of Schedule 2 development requires EIA even if it is not to be located in a sensitive area and

does not exceed or meet the applicable threshold or criterion.

The more environmentally sensitive the location, the more likely it is that the effects of development will be significant and that EIA will be required. That is why the thresholds and criteria do not apply where development is proposed in, or partly in, a `sensitive area' as defined in the Regulations. Such areas include Sites of Special Scientific Interest (SSSIs), National Parks, Areas of Outstanding Natural Beauty, the Broads, World Heritage Sites and scheduled monuments.

There is no general presumption that every Schedule 2 development in a sensitive area will require EIA. Nevertheless, in the case of development to be located in or close to SSSIs, especially those which are also international conservation sites such as Ramsar sites or Special Protection Areas for birds, the likely environmental effects will often be such as to require EIA.

Agriculture Intensive agriculture, irrigation, drainage fish farms.

Extractive Industry Quarries, mines, dredging, deep drilling, fossil fuels.

Energy Industry Steam raising, fuel storage, fuel briquetting, hydroelectric, wind farms (0.5 MW).

Processing of Metals Pig iron, mills, foundries, melting of non-ferrous alloys, electroplating: ship, aircraft, railway and road vehicle manufacturers works.

Mineral Industry Coke ovens, cement, asbestos, glass fibre, mineral fibre, ceramic works.

Chemical Industry Intermediate production of chemicals, production of pharmaceutical products, paint, pesticides and some other chemicals; storage of petroleum etc.

Food Industry Manufacture of oil and vegetable fat, dairy products, confectionery, syrup, starch or sugar, slaughterhouses; brewing and malting; fish-meal and oil processing.

Textile, leather, etc. Paper and board, dyeing, tanneries, ceullulose production.

Rubber Manufacture of elastomer-based products.

Infrastructure projects Industrial estates, urban developments and trans-shipment facilities, railways, airfields, roads, harbours, waterways, flood relief works (river and coastal) dams, oil and gas pipelines, aqueducts, groundwater abstraction, motorway service areas.

Tourism and leisure Theme parks, holiday villages, caravan sites, golf courses, sports stadia, ski runs.

Table 2. Developments that require an EIA under Schedule 2

Question 1.

Environmental Impact Assessment ....

Multiple Choice (HP)

Answer 1: Helps promote a sustainable pattern of physical development

Response 1:

Jump 1: This page

Answer 2: Draws together an assessment of a projects likely significant environmental effects

Response 2:

Jump 2: This page

Answer 3: If properly carried out, benefits all those involved in the planning process

Response 3:

Jump 3: This page

Answer 4: All of the above

Response 4:

Jump 4: Next page

Question 2.

Who is involved in an Environmental Impact Assessment?

Multiple Choice (HP)

Answer 1: General public

Response 1:

Jump 1: This page

Answer 2: Developer

Response 2:

Jump 2: This page

Answer 3: Planning authority

Response 3:

Jump 3: This page

Answer 4: All of the above

Response 4:

Jump 4: Next page

2.4 'Permitted Development Rights' (PDRs).

Developments which do not require planning permission because of the provisions of the Town and Country Planning (General Permitted Development) Order 1995 (SI No 418) continue to enjoy permitted development rights, provided that they do not fall into Schedule 1 or 2 of the EIA Regulations. For developments that do fall within Schedule 1 or 2, the general position is as follows:

Schedule 1 projects are not permitted development, and always require the submission of a planning application and an environmental statement.

PDRs for Schedule 2 projects which either exceed or meet the applicable threshold or criterion, or are wholly or partly in a sensitive area, are also withdrawn, unless the local planning authority has adopted a screening opinion (or the Secretary of State (or, in Wales,

the National Assembly for Wales) has directed) to the effect that EIA is not required.

There are exceptions to these provisions in the case of the following classes in Schedule 2 to the 1995 Order:

Part 7, Class D of Part 8, Part 11, Class B of Part 12, Class F (a) of Part 17, Class A of Part 20, Class B of Part 20, and Class B of Part 21.

These exceptions exist for a variety of reasons; for example, some relate to projects subject to alternative consent procedures, and others to projects begun before Directive 85/337/EEC came into operation.

http://www.legislation.hmso.gov.uk/si/si1995/Uksi_19950418_en_1.htm

2.5 Screening & Scoping.

Screening refers to the decision as to whether an EIA is required or not. In the UK, this is a decision that can be taken by the developer and often will be if the project is of a type or size where an EIA is clearly required or if they wish to be seen to be addressing the environmental effects of their development.

For most projects, particularly those covered by Annex 2 of the directive, the determining authority is likely to be asked to give a screening opinion. Their decision will be based on the type of criteria included in Annex 3 of the directive, more detailed guidance issued by the European Commission and the government and the opinions of government agencies (e.g. English Nature and the Environment Agency) and relevant local authority personnel (e.g. environmental health officers).

Scoping

The purpose of EIA is to focus on thesignificant environmental effects of a development. The purpose of scoping is to identify the effects that are most likely to be significant in order to focus the time and resources devoted to the EIA on the important issues. The identification of the key effects is usually undertaken using a combination of professional judgement and gathering the opinions of others, particularly the determining authority and other government agencies.

Scoping is usually undertaken by those responsible for the EIA. However, there is provision in the EIA Directive for the developer to request a 'scoping opinion' from the determining authority. When this is requested, it is usually accompanied by a report that outlines what the developer and consultants consider to be the most important issues. The determining authority will consult with other government agencies (statutory consultees) and amend or add to the developer's report accordingly.

The advantage of seeking a scoping opinion is that the developer will have some assurance that the issues being addressed by the EIA will be those that are considered to be important by the determining authority when a decision is to be made on the project.

To a degree, the scoping stage of an EIA continues throughout the process, for example, the identification of an unacceptable environmental effect may lead to a redesign of the project, which in turn could lead to the main environmental effects of the project changing, hence the scope of the EIA will also change.

An applicant for planning permission may ask the local planning authority (LPA) for a screening opinion before submitting the application. The LPA must decide whether the development proposal is likely to fall within Schedule 2 and will therefore require an EIA. Schedule 3 to the regulations lists the type of information that must be considered when deciding if an EIA is needed. The scoping opinion is a letter from the LPA which guides the applicant on the areas of work to be included in the EIA and ensures that all concerns are addressed. The LPA then has five weeks to provide its opinion on the likely significant effects on the environment and other impacts and issues. The scoping opinion document then forms the basis for the full environmental impact assessment.

It must be noted however, that in some circumstances there is provision for the Secretary of State to become involved, although the procedure still follows the similar lines as illustrated in the flow chart (seen in the following pages).

2.6 Characteristics of the Development.

How will 'Significance' be assessed? Developments which meet or exceed the applicable threshold are considered on a case-by-case basis. For the purpose of determining whether EIA is necessary, those of the selection criteria set out in Schedule 3 to the Regulations which are relevant to the proposed development, must be taken into account. The selection criteria fall into the three broad headings: size of the development, location of the development, and characteristics of the potential impact.

Size

Combined effects with other developments. Use of natural resources. Production of waste. Pollution and nuisance. Risk of accidents.

Location of the development

Existing land use. Natural resources in the area. Absorption capacity of the natural environment. Areas where environmental quality standards have been exceeded. Densely populated areas. Landscapes of historical, cultural or archaeological significance.

Characteristics of the potential impact

Extent including the area of the development and number of people. Transfrontier impacts. Magnitude and complexity. Probability of the impact.

Duration, frequency and reversibility of the impact.

For obvious reasons there can be no general definition of what constitutes significance. General guidance on how to assess `significance' is contained in DETR Circular 2/99 (Welsh Office Circular 11/99); and rulings may be obtained from the local planning authority or the Secretary of State (or, in Wales, the National Assembly for Wales) on whether EIA is required in particular cases. Essentially, the Circular suggests that there are three main criteria of significance:

i. major developments which are of more than local importance;

ii. developments which are proposed for particularly environmentally sensitive or vulnerable locations; these include

Sites of Special Scientific Interest (SSSIs), nature conservation areas; National Parks and the Norfolk Broads; World Heritage Sites; Ancient monuments and archaeological areas; areas of outstanding natural beauty (AONB); special conservation areas.

iii. developments with unusually complex and potentially hazardous environmental effects.

These are very general guidelines and, to assist in their application to particular cases, the Circular also sets out indicative thresholds and criteria by reference to particular categories of development listed in Schedule 2 to the Regulations.

It will be obvious that none of these guidelines can be applied as hard and fast rules; circumstances are bound to vary greatly from case to case. Some large-scale projects which exceed the indicative thresholds may not be significant enough to require EIA; some smaller projects, particularly in sensitive locations, may be candidates for EIA. Nevertheless, the guidance in the Circular should provide a starting point for consideration by the developer and the planning authority of the need for EIA. If the matter is referred to the Secretary of State (or, in Wales , the National Assembly for Wales ), he will have regard to the published criteria.

2.6.1 EIA Flow Charts.

2.7 Procedures for the Preparation & Submission of Formal Environmental Statement.

The Environmental Impact Assessment is then embodied in an environmental impact statement (EIS) which is now often required by law before a new project can proceed.

Information that should be included in environmental statements

1. A description of the proposal

This should include detailed drawn plans. These tend to be a maximum size of A3 folded to A4. Generally, these are less detailed than the formal plans submitted with the application.

2. An outline of the alternatives considered

Alternatives may include alternative fuel sources, locations or processes which may use different raw materials. The choice of proposal should be justified.

3. A description of the environment likely to be affected

All of the potential impacts both adverse and beneficial of the development should be considered and the activities, operations and processes that give rise to the effects should be identified. Pathways between the source of the pollution and the receiver should be identified. Please refer to the Source, Pathway, Target model of pollution figure below:

Human Beings Population - changes, inward/outward migration. Housing - temporary construction/permanent. Services - demand for hospitals/schools/shops etc.

Noise Industrial noise. Transportation noise. Leisure noise. Domestic noise.

Vibration Blasting. Construction. Demolition. Track. Machinery.

Traffic & Transport Noise/vibration. Air Pollution. Visual Impact. Capacity.

Land Use Agriculture-land quality. Rural economy access and severance. Land drainage. Forestry species, yield, loss of timber, impacts on remaining

trees, future management, habitats/wildlife. Mineral extraction/waste disposal.

Flora & Fauna (ecology)

Pollution-soil/water/air. Micro-climate.

Groundwater. Hydrology. Disturbance. Habitat inter-relationships. Indirect-distant loss.

Soil, geology & hydrology

Soil loss, destruction, physical damage. Contaminated land. Chemical-metals, organic wastes, gases, radionuclides. Geology-instability, Sites of Specific Scientific Interest

(SSSI). Hydrogeology-alteration to groundwater flow/derogation of

supply/contamination.

Water Run-off changes to catchment / surface characteristics. Groundwater resources. Water quality.

Air and Climate Odour. Dust. Combustion products (power). Traffic emissions. Manufacturing emissions. Landfill gas.

Landscape Character/history of landscape. Nature/extent of landscape changes. Status of landscape (national/regional). Significance in terms of value-scenic value, rarity, typicality. Visual impact - zone of visual influence.

Cultural heritage & Material assets

Archaeology/monuments - marine and land. World heritage sites. Historic (listed) buildings. Conservation areas. Historic landscapes. Parks and gardens. Battlefields.

Table 1 Environmental Impacts

2.8 Likely Significant Effects on the Environment.

The pollutant emissions due to the operation of the development should be estimated. Next the impacts have to be assessed, predicted and - wherever possible - quantified. The direct and indirect impacts have to be assessed as well as the long-term, medium-term and short-term effects. Some impacts could also be reversible and this should not be overlooked. Each environmental effect under consideration will probably require a different method of prediction assessment, from scientific such as noise monitoring to a combination of science, experience and good judgment.

The EIA does not consider the concept of the best practicable environmental option (BPEO)

although it is included in when considering alternative proposals and operations.

The UK Environment Agency, however, moves closer to this concept under the IPPC regime for permitting certain industrial installations.

The assessment of the emissions to air can be quite complex due to the need to address local, national and possibly international aspects.

The assessment of the emissions will have to include, as appropriate, the following:

Fixed sources (e.g. flues, chimneys and exhausts). Mobile sources (e.g. vehicles and mobile plant). Fugitive emissions (e.g. escape through open doors or during delivery of chemicals,

raw materials or dust blowing off stockpiles or yards.

Particular attention must be paid to pollutants which have the potential to harm human health or the environment.

The assessment of the impacts will often be based on a combination of measurements and predictions. Background data will be required in order to assess the impacts, but one of the problems is the need to measure over a long time period.

2.8.1 Impact on Land.

There are two principal routes for soil contamination: direct contamination and indirect contamination. The former is often as a result of leachate, spillage or the polluting material directly entering the soil. The latter can be from airborne pollutants being washed into, or deposited on, the ground. The need to address contaminated land issues was recognised by the government and procedures were laid down by the Environment Act 1995.

An adequate EIA, including appropriate mitigation measures, should ensure that land contamination, as defined in the 1995 Act, does not occur. Contaminated land is defined in the Environment Act 1995 as 'land which can cause, or is likely to cause, significant harm i.e. harm to the health of living organisms or to other ecological systems or damage to property.'

Noise and Vibration

The impacts of noise are varied and site specific and one of the key issues concerning noise impacts is the difference between the noise emission and the background levels. Vibration will mainly affect people in buildings, and the responses vary according to the type of vibration.

Impacts on Water

There are two major potential impacts to the water medium: hydrological or polluting and their consequences include:

surface run-off to watercourses such as ditches, streams, rivers or canals; raising or lowering the water table.

Whilst these impacts should be in included in an EIA, they are beyond the scope of this course.

2.9 Measures to Reduce or Offset the Impacts.

For each of the media considered, there may be a need to describe some of the measures that will be incorporated into the development to ensure that the environmental impact of the proposal is acceptable. In most cases, the mitigation will be site-specific and influenced by the media likely to be affected as well as the pollutant.

Air

In some situations, it can be difficult to control emissions to air, particularly with emissions from transport and fugitive emissions.

Land

The land contamination issues are likely to be most complex when brownfield sites are being redeveloped. The UK Government is actively encouraging the redevelopment of brownfield sites for a range of uses, including residential development.

Noise

Noise mitigation can be of many types but the key opportunities include practices and systems to reduce or control noise, and specific noise mitigation measures. Noise control methods can include:

enclosures; louvres; barriers; quiet road surfaces; distance; silencers; lagging.

Active noise control

Noise can be dramatically reduced by producing exactly the same noise at the same volume as the source noise but 180 degrees out of phase. The effect is zero pressure and hence silence theoretically.

Good noise management can significantly reduce the impact of noisy operations. This may simply be in accordance with accepted custom and practice or it may be formalised into a noise management plan.

Water

In the case of water, mitigation could include design, maintenance of plant and equipment, design of drainage, sewerage and effluent treatment systems and bunding around storage tanks.

2.10 A Non-Technical Summary.

This must be included in the Environmental Impact Assessment. It should include a description of the proposed development, any environmental impacts relating to it and any measures needed to mitigate the impact.

There also needs to be an indication of any difficulties encountered when compiling the Environmental Impact Assessment. Some aspects of the Environmental impact assessment may be difficult to assess for a variety of reasons, including insufficient time to collect enough background data, or the time of the year preventing the assessment of some of the flora and fauna present on a site. Uncertainties in prediction and assessments should be included in the statement.

2.11 Submission of the Environmental Statement with the Planning Application.

To enable a planning application to be processed as quickly as possible, it is in the developer's interest to submit an environmental statement at the same time as the application is made. It will be for the planning authority to judge how much information is required in the particular case, but the preparation of an environmental statement is bound to require the developer to work out proposals in some detail; otherwise, any thorough appraisal of likely effects will be impossible.

Where an application is in outline, the planning authority will still need to have sufficient information on a project's likely effects to enable it to judge whether the development should take place or not. The information given in the environmental statement will have an important bearing on whether matters may be reserved in an outline permission; it will be important to ensure that the development does not take place in a form which would lead to significantly different effects from those considered at the planning application stage.

When the developer submits an environmental statement at the same time as the planning application, three further copies must also be submitted for onward transmission by the planning authority to the Secretary of State (or, in Wales, the National Assembly for Wales ).

The developer is also required to provide the planning authority with sufficient copies of the environmental statement to enable one to be sent to each of the statutory consultees. Alternatively, the developer may send copies of the statement directly to the consultees. When submitting the application, the developer must inform the planning authority of the name of every body - whether or not it is a statutory consultee - to which a copy of the statement has been sent.

The developer should make a reasonable number of copies of the statement available for members of the public. A reasonable charge reflecting printing and distribution costs may be made.

2.12 Submission of the Environmental Statement with the Planning Application (Cont.).

Public consultation and participation aims to assure the quality, comprehensiveness and effectiveness of the EIA, as well as to ensure that the public's views are adequately taken into consideration in the decision-making process.

EIS presentation is a vital step in the process.

EIA may be negated.

If done badly, much good work in the EIA may be negated.

The review involves a systematic appraisal of the quality of the EIS, as a contribution to the decision-making process.

Decision-making on the project involves a consideration by the relevant authority of the EIS

(including consultation responses) together with other material considerations.

Post-decision monitoring involves the recording of outcomes associated with development impacts, after a decision to proceed. It can contribute to effective project management.

Auditing follows from monitoring. It can involve comparing actual outcomes with predicted outcomes, and can be used to assess the quality of predictions and the effectiveness of mitigation. It provides a vital step in the EIA learning process.

The environmental impact statement provides documentation of the information and estimates of impacts derived from the various steps in the process. An EIS revealing many significant unavoidable adverse impacts would provide valuable information that could contribute to the abandonment or substantial modification of a proposed development action. Where adverse impacts can be successfully reduced through mitigation measures, there may be a different decision. An example of the content of an EIS for a project is given below:

Documentation

Part 1: Methods and key issues

1. Methods statement.

2. Summary of key issues', monitoring programme statement.

Part 2: Background to the proposed development

3. Preliminary studies: need, planning, alternatives, site selection.

4. Site description/baseline conditions.

5. Description of proposed development.

6. Construction activities and programme.

Part 3: Environmental impact assessment

A description of the likely significant effects (direct and indirect) on the environment, explained by reference to the following areas:

7. Land use, landscape and visual quality.

8. Geology, topography and soils.

9. Hydrology and water quality.

10. Air quality and climate.

11. Ecology: terrestrial and aquatic.

12. Noise.

13. Transport.

14. Socio-economic cultural heritage, employment, education, housing etc.

15. Interrelationships between effects.

A non-technical summary is an important element in the documentation.

EIA can be complex and the summary can help to improve communication where public participation is involved. Reflecting the potential complexity of the process, a method statement, at the beginning, provides an opportunity to clarify some basic information (e.g. who is the developer, who has produced the EIS, who has been consulted and how, what methods have been used, what difficulties have been encountered and what are the limitations of the EIA).

A summary statement of key issues, up-front, can also help to improve communications. More enlightened EIS would also include a monitoring programme, either at the beginning or at the end of the document. The background to the proposed development covers the early steps in the EIA process, including clear descriptions of the project and baseline conditions (including relevant planning policies and plans). Within each of the topic areas of the EIS, there would normally be discussion of existing conditions, predicted impacts, scope for mitigation and residual impacts.

EIA and EIS practice vary from study to study and from country to country and best practice is constantly evolving. Greater emphasis is now being given to the socio- economic dimension, to public participation, and to ''after the decision'' activity, such as monitoring.

Question 3.

Assessment of emissions to the air will have to include (as appropriate) ...

Multiple Choice (HP)

Answer 1: Mobile sources (vehicles & mobile plant)

Response 1:

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Answer 2: Fixed sources (flues, chimneys & exhausts)

Response 2:

Jump 2: This page

Answer 3: Fugitive emissions (those escaping through open doors or during delivery)

Response 3:

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Answer 4: All of the above

Response 4:

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3.0 Environmental Modelling.

Principles and application of environmental modelling and their limitations.

Environmental modelling is a useful tool for understanding and predicting environmental changes over various times and areas. Models can be used to explore ideas regarding

environmental systems that may not be possible to field-test for logistical, political or financial reasons. The process of formulating a model can be extremely valuable for organising thought, identifying hidden assumptions and identifying data needs. Fast computers and graphical software packages have removed the drudgery of computation and opened up new areas of model construction.

A model is a representation of a particular thing, idea or conditions. It can be as simple as a verbal statement about a subject, or a single relationship between two things or extremely complex and detailed, e.g. climate change models.

In this course, you are not expected to be able to develop or use the models discussed below, but to have an understanding of what models are used for, their applications and some of their limitations.

3.1 Steps in Model Creation and Use Develop Conceptual Model.

These are generally written as diagrams with boxes and arrows to provide a compact visual statement of the problem. The model should incorporate sufficient detail to capture the necessary environmental structure and processes, and still be simple enough to be useful. It should enable the analyst to formulate hypotheses, identify the available data and the additional data that are required.

Develop Quantitative Model

A quantitative model is a set of mathematical expressions, coefficients and data attached to a conceptual model. These enable predictions to be made for the values of state variables under varying circumstances.

Sensitivity analysis of a quantitative model can identify which processes and coefficients have the greatest effect on the results. It explores whether the conclusions would change if the parameters, initial values or equations were different.

Models can be based on empirical (observed) data or they can be more mechanistic, being based on hypotheses regarding the processes involved. They can become quite complex, particularly when they are used as a basis for policy and resource management decisions. Often they are used to generate predictions for situations where actual tests are impossible to run, due to environmental, social or economic reasons, or where the timescales involved are too long, e.g. impact over 100 year time span .

Deterministic and Stochastic Models

A deterministic model has no random components and every time it is run with the same parameters and conditions, the same results will be produced. In contrast, a stochastic model has at least one random factor, to produce different results each time the model is run, simulating environmental variability. The randomness can be introduced using probability distributions, by adding random errors or by using random number generators. Results are usually cast as probabilities.

3.2 Typical Scales of Environmental Models.

Some common scaling problems include:

Difficulties in aggregation of large-scale behaviour from local processes due to spatial variation and non-linear processes.

Different processes predominate at different scales; correlations derived at one scale

may not be appropriate at another. The interaction between processes operating at different scales, e.g. small, fast local

processes may be constrained by large, slow ones. Emergent properties from mutual interaction of small-scale components. Temporal lags in the response of a system to perturbation.

GIS and Environmental Modelling

As many environmental models involve a spatial component, they lend themselves to the use of GIS (Geographical Information and Spatial Referencing Systems). The inputs and outputs can be stored in an efficient fashion and easily related to information from other sources, e.g. farm boundaries or land use, and it is possible to link these to the high-quality graphics and animation capabilities of GIS in a way that makes it possible to convey abstract technical concepts and modelling to a non-technical audience.

Scaling

Scientific knowledge of environmental processes has largely been developed through their study at a local level. Study at this level reveals the critical causes of environmental change and the processes can be accurately simulated. However, the problems affecting us now are often expressed on regional and global scales.

Example Applications

Climate change. Surface water. Groundwater. Watershed/water catchment. Ecosystem.

3.3 Dispersion and Transport of Pollutants in the Atmosphere.

A pollutant plume emitted from a single source will be transported in the direction of the mean (average) wind. It is acted upon by the prevailing level of atmospheric turbulence,

which causes the plume to grow in size as it enters the (usually cleaner) air. There are two main methods of generating atmospheric turbulence: mechanical turbulence (generated as the air flows over obstacles on the ground), and convective turbulence (associated with solar radiation).

Air Modelling Use of Models

Models are used for regulatory purposes to show compliance with a given set of parameters, given as part of a legal permit (as for example, under the Pollution Prevention and Control Regulations 2000). They are also used for support of a given policy or course of action, for the provision of public information, or for use in scientific research.

Dispersion models describe how pollutants are spread and mixed in the atmosphere. Mathematical procedures are used to calculate pollutant concentrations based on emission rates (mass of pollutant emitted over time) and dilution rates (the volume of surrounding air into which the pollutant is being mixed, per unit time). In this way, dispersion models link measured air quality with emissions data.

In air pollution assessments, all parts of the cause and effect chain have to be evaluated, and whereas air quality monitoring may be defined as the systematic collection of information from measurements and other means, monitoring alone will not achieve the best possible description of the concentration or space/time relationships. Spatial scales may vary from street level up to the global scale, and although measurements may form an important part of monitoring, for many purposes, models are often needed to establish larger scale average exposures or deposition fields.

The reasons for modelling include greater representation of effects under changing conditions, such as release quantities, meteorological conditions or to account for the local topography. Models can also be used to predict the effect of various sources and emission scenarios.

3.4 Types of Model.

The following types of model can be distinguished:

Plume rise models: in most cases, pollutants injected into ambient air from chimneys or stacks possess an initial momentum. Plume rise models calculate the displacement and general behaviour of the plume in the initial dispersion phase.

Gaussian models: the Gaussian plume model is the most common air pollution model, based on the assumption that the plume concentration has a predicted size and shape, which can be represented by a known mathematical equation.

Semi-empirical models: this category consists of several types of model used for practical applications.

There are many other specialist models available, e.g. Eulerian models, Lagrangian models, chemical models, receptor models and stochastic models. Each have uses for specialist circumstances, which are beyond the scope of the syllabus.

3.5 Gaussian Model: the Gaussian Plume Approach.

The Gaussian Plume Model will be discussed because it gives results adequate for most practical applications and the quality of the emission and meteorological data does not justify the use of the increased resources required to run more complex models.

In the Gaussian Plume approach, the expanding plume has a Gaussian (or Normal )

distribution of concentration in the vertical and lateral directions. This approach is used for modelling a plume emission from 0-100 kms. Variations of this straightforward approach lead to increasing mathematical complexity and are a specialised subject outside of the requirements of the syllabus.

Uses of Atmospheric Models

Atmospheric models are broadly any mathematical procedure which results in the estimation of ambient air quality parameters (concentrations, depositions and exceedances). Process-orientated models are based on the description of physical and chemical processes, starting with emissions, atmospheric advection and dispersion, chemical transformation (from one chemical to another, as in the formation of acids from emissions of sulphur oxides) and deposition. Statistical models are valuable tools in the diagnosis of air quality by means of the interpolation and extrapolation of measuring data.

As an environmental manager, you may have to use a specialist company to model releases as part of legislative requirements. Models may be needed, for example, to predict the effects of a deposition after an unplanned release of pollutants, as required under the COMAH Regulations. They can also be used to improve emission inventories, monitoring programmes and assist in planning control measures. Models are therefore indispensable in air quality assessment studies, and can be used to estimate past, present and future air quality.

There are limitations to the use of these models; once a model has been developed, it is relatively easy (and inexpensive) to use the model for further applications. However, collecting the necessary input data can be expensive and cumbersome. Uncertainties in model results can be large, as they may be introduced by the model concept and the input data (emission data and meteorology).

It is important to be aware that predictions from climate models are always subject to uncertainty because of limitations on our knowledge of how the climate system works, and on the power of the computing resources available. Different climate models can give different predictions.

Question 4.

Stochastic models have no random components and every time it is run with the same parameters and conditions, the same result will be produced?

True/False (HP)

Answer 1: True

Response 1:

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Answer 2: False

Response 2: Stochastic models have at least one random factor in order to produce different results. It is Deterministic models that have no random components.

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3.6 Dispersion in Water.

The following information is taken from SEPA (Scottish Environment Protection Agency); there is more detail here than you will be required to remember for the NEBOSH

examination, but it is included to enable you to understand and appreciate the subject. Again, it is not the expectation of the examiners that you are able to construct a model of this type, but you are expected to have an understanding of the parameters and considerations made in developing a model.

The impact of a discharge on any water body is dependent on discharge quality and quantity, and prevailing physical and chemical conditions of the waters receiving the discharge. In contrast to a river, the physical and chemical conditions of tidal waters are highly variable, both spatially and temporally due to tide and wind currents, the bathymetry of the sea bed and seasonal river flow and quality.

Therefore, in order to assess the impact of a discharge to a tidal water body, it is necessary to predict the duration over which the pollutants may act, the area of impact and whether any other discharges (diffuse or point) might impact the same area. This assessment is normally made with some form of predictive model to enable simulation of different discharge quality parameters, in combination with the different physical and chemical conditions of the receiving waters.

Models vary greatly in type and complexity, but it is essential that the model chosen is appropriate to the situation in which it is being utilised. It is also important that the model is properly calibrated and validated, in order to ensure that the model output is reliable and accurate. Once again, this is a specialist area which requires an expert in the field to carry out the modelling process.

In the case of water modelling, the amount of data and the complexity of the data will depend on whether the water system is a river, an estuary or coastal system. This is because tidal effects, mixing effects and degrees of salinity all affect the behaviour of pollutants.

3.7 Defining the Model.

It is essential to define the major issues and variables under consideration at the outset, in order to select an appropriate model:

Model Grid constitutes key data such as depth, topography, river inputs, tidal elevations, flows at boundaries, etc. needed to calibrate and validate the model.

Model Duration is the temporal extent of the discharge. It defines the duration over which the model simulates processes, which may be a number of tidal cycles, days, weeks, months or even years.

Model Domain is the spatial extent of the model, determined from a knowledge of the location and temporal effect of the discharge.

Model Dimensionality is decided once the model domain and duration is known. It requires knowledge of the hydrography of the area and behaviour of the pollutants. It describes how the area is divided:

One-dimensional model (1D) has a single scale, e.g. length down an estuary.

Two-dimensional model (2D) has two scales, e.g. length and depth of estuary.

Three-dimensional model (3D) has three scales; length, width and depth. With ever-increasing computing power, 3D models will become more attractive as the real

problem is three dimensional, and using a 3D model removes another simplifying assumption.

3.8 Model Types.

The three basic types of model are described below.

Hydrodynamic Model

The hydrodynamic model predicts the surface elevations and current velocity field across the model grid. It provides the flow and dispersion data that can be used to run other models, such as water quality or particle tracking. This frequently includes the dispersion of a conservative tracer, commonly calibrated against observations of salinity in marine work. Although these models can be quite time-consuming to run, once run the output files can be used to model scenarios for different outfall locations and conditions.

Water Quality Model

Water quality models simulate the chemical reactions that take place within the water body modelled. Depending on the requirements of the study, the simulation can be limited to a single determinant, or a number of determinants. The more complex the model, the more complex the data required to set-up, calibrate and validate the results.

It is important that the tool used is demonstrated to be suitable for the problem to be solved. A common error is to implement a model that is more sophisticated than required and then encounter problems with calibration and validation.

Particle Tracking Model

Particle tracking models simulate the behaviour of compounds or organisms in the water column by representing them as a number of particles. These are adverted and dispersed throughout the water body using a flow field obtained from a hydrodynamic model or from surveys. The model simulates the behaviour of these particles over time, including processes such as bacterial die-off or variable buoyancy.

These models run much faster than most water quality or hydrodynamic models, as they read the flow field from data files rather than computing them. The model tracks and records the movement of particles through time. Another advantage of these models is that runs can be made for different environmental conditions and percentile plots of compliance may be created. Particle tracking is commonly used for bacterial modelling.

3.9 Model Set-Up.

Data Requirements

Data are required to set-up the model and to validate and calibrate the model against observations. The set-up data are required to define the bathymetry within the model, and to provide boundary and initial conditions. Remember that the data inputted into the model are the key factor; without valid data, the model predictions cannot represent the likely situation. In some cases, adequate data are difficult to obtain and this should be explained in the model results.

Boundary conditions are necessary to describe the inputs to the models, which may be riverine or point source discharge data, plus tidal flow and elevations at the seaward

boundary of the model.

Initial conditions data are required to set parameters, particularly water quality, at the start of the model run. This could be water depth or the number of plankton per square metre.

Model Calibration

Calibration is the process by which the model is adjusted to reproduce the characteristics of the study area, for a given set of conditions. The model output is compared against observed measurements and model parameters and coefficients are adjusted to improve agreement.

Calibration data for hydrodynamic models may consist of water levels, current speeds and directions, drogue tracks, salinity measurements and dye-tracking data. To achieve calibration of the tidal cycle, the model is often compared to tidal heights or flows that have been harmonically analysed to remove the wind effect from observations.

However, if the model is to be used to simulate wind effects, it is equally important that the model is compared against the observed data.

Other important considerations for hydrodynamic model calibration are:

Location and number of data points.

Accuracy of calibration data.

Distribution of data with respect to model dimensionality; vertical and lateral required level of agreement between model output and observations from field surveys, sampling, etc, for example, is the model fit for purpose and what degree of adjustment is necessary to demonstrate agreement?

Typically, the model resolution, the bathymetry and sea bed roughness coefficient are adjusted to improve agreement to the desired level. Good agreement between predicted and observed salinities and dye-tracking results is necessary to demonstrate that the model accurately reproduces the dispersive characteristics of the study area. This is essential to achieve accurate water quality simulations.

Calibration data for water quality models consist of concentrations of the variables of interest at points throughout the model area, over the period of interest. Seasonal variations may be important for some parameters, such as nutrients and chlorophyll. The considerations listed previously for hydrodynamic calibration are important for water quality calibration. In addition, it is important that all inputs to the model area, e.g. from outfalls or rivers are accurately specified.

The reaction rates and coefficients in equations describing chemical kinetics in the water column are adjusted to improve agreement between water quality predictions and observations to the desired level. In general, the level is less for water quality than for hydrodynamics because of greater environmental variability of water quality parameters.

3.10 Model Validation.

This demonstrates model accuracy by comparison of model output with a separate, independent data set. The model should provide good agreement without further adjustment.

Sensitivity Testing

Once a model has been set-up, calibrated and validated, it is important to test the sensitivity of the model output to the key input parameters, i.e. the boundary and initial conditions. A model report should always include a section on sensitivity testing, demonstrating the variation in model output in relation to variation in the input data.

Some models have automatic sensitivity testing routines, others require the operator to make a number of runs while manually varying the input parameters. It is important to check and understand model sensitivity to both boundary and initial conditions.

Initial Dilution

Effluent discharged to tidal waters is typically buoyant due to the difference in density between the effluent and surrounding saline waters. Without adequate initial dilution, effluent upwelling can create surface slicks, causing significant aesthetic impact at the very least.

Initial dilution is the process whereby the discharge from a submerged outfall is entrained by surrounding waters, as a result of turbulent mixing and discharge buoyancy relative to ambient water density. The main factors controlling the initial dilution afforded by an outfall are:

water depth; ambient current; effluent density; outfall diffuser design (number of ports, port diameter, discharge rate, etc.).

It is normally calculated using a stand-alone model or set of equations and then factored into the inputs of a more detailed model.

3.11 Estuarine Modelling.

Estuaries may receive a number of major discharges in proximity, requiring that any model takes account of combined inputs. Thus, estuarine modelling studies benefit from detailed knowledge of all contributing sources. This is important when modelling overall impact, as opposed to the effect of a single discharge.

Estuaries are characterised by a longitudinal variation in salinity from coastal seawater at the seaward boundary to zero at the upstream fresh water boundary. Conditions within an estuary are dynamic and complex through the combination of tidal forcing, winds and variation in freshwater inputs. Longitudinal and lateral variations in salinity, and hence water density, can have a significant effect on estuarine hydrodynamics, mixing and subsequent water quality. Selection of an appropriate numerical model with the capability to reproduce these features (if present) is essential.

Conditions within estuaries can vary from well-mixed to partially-mixed to stratified, depending largely on tidal range, but also on depth and fresh water input. In a well-mixed estuary, longitudinal variability is most significant and it is often acceptable to assume lateral and vertical variations are small and thus a 1D time varying model (dynamic) is the most appropriate choice. For hydrodynamics, this will simulate tidally forced variations in water level and current velocity along the length of the estuary. The model output corresponds to cross-sectionally averaged conditions at any point along the length of the estuary.

If estuary width is significant but there is good vertical mixing, then a 2D depth-averaged

model may be appropriate. These models predict lateral variations in conditions. However, if vertical stratification is significant due to temperature and density differences, but lateral variations are small, a 2D width-averaged model is most appropriate. Finally, if both width and depth variation are important within the areas of interest, a 3D dynamic model is required.

Estuaries can be prone to Dissolved Oxygen (DO) depletion and are a major source of nutrient inputs to coastal waters, from both natural and anthropogenic (man-made) sources. Therefore, the water quality model chosen must be capable of simulating complex processes and relationships.

Coastal Waters

Coastal waters, in contrast with estuaries, are generally less bounded, with reduced significance of freshwater inputs. However, lateral variability can seldom be ignored and the significance of wind effects is greater. It is often reasonable to build a model to simulate only one specific discharge.

Although the model domain might include other sources, it may be reasonable to demonstrate that the effects of the discharges under consideration will not overlap. The model domain is often much larger for a coastal model and the water quality models may be more sophisticated wherever the issues include eutrophication (an increase in the concentration of chemical nutrients in an ecosystem to an extent that increases the primary productivity of the ecosystem).

Spatial variability generally requires at least a two-dimensional model. When depth variation can be demonstrated to be negligible, a 2D depth averaged model is appropriate. The location of the seaward boundary is often critical both for the provision of reasonable data and in determining the area of impact for the model. In areas where both lateral and vertical structure are significant, 3D models are necessary. This may be caused by water depth, low tidal energy, seasonal density patterns possibly increased freshwater influence in winter or increased surface warming in summer.

3.12 Limitations of Monitoring and Modelling.

A single sample for one process will seldom be an adequate basis for control decisions.

The means of data collection, the accuracy of the data analysis and the limits of accuracy of the test/detectable limits and all the factors relating to the reliability of the information must be sought. The relevant factors relating to the monitoring and/or sampling must be recorded along with the results as a reference. This information may include nature of the sample, method of collection and analysis, relevant local conditions including meteorological conditions, and time and temperature at the time of sampling.

Modelling, Monitoring and Control

Monitoring is not a means of control. It is a means by which failure and defects in control are made apparent, and a means of demonstrating the continued effectiveness of controls.

4.0 Life Cycle Analysis.

Definitions:

Definitions of Life Cycle Analysis (LCA) differ in detail. The Society of Environmental

Toxicology and Chemistry (SETAC) definition is:

''Life cycle analysis is an objective process to evaluate the environmental burdens associated with a product, process or activity by identifying and quantifying energy and materials used and wastes released to the environment, and to evaluate and implement opportunities to affect environmental improvements. The assessment includes the entire life cycle of the product, process or activity, encompassing extraction and processing raw materials, manufacturing, transportation and distribution, use/re-use/maintenance, recycling and final disposal''

A second definition is:

''Environmental LCA or product life analysis (PLA) are detailed studies of the energy requirements, raw material usage and water, air, and solid wastes generation of an activity, material, product or package throughout its entire Iifecycle.

4.1 Cradle-to-Grave Concept.

When we refer to a product's life cycle, we mean from the 'cradle' (extraction of raw material) to the 'grave' (when the product is discarded).

The use of life cycle analysis enables organisations to adopt a holistic approach to their environmental assessments whilst allowing them to identify their significant indirect environmental aspects. Life cycle analysis can be conducted at any part of the life cycle such as at the stages before manufacture, or nearer the end of life stage to identify and minimise the environmental effects of a companys operations.

Life cycle analysis is not a requirement of an Environmental Management System (EMS) (or ISO 14001) and EMAS.

Use of life cycle analysis depends upon:

1. the problem in question; 2. the resources available; 3. the time available for reaching a decision.

Life cycles analysis compiles material, energy and waste flows and evaluates the environmental impacts associated with the provision of a product or service throughout its life cycle.

As life cycle analysis views the wider picture, it differs from many other environmental assessments which merely consider elements that make up a stage in the life cycle.

There are also important distinctions between life cycle analysis and life cycle assessment. Life cycle analysis is the collection of data it produces an inventory whereas assessment goes one stage further and adds on an evaluation of the inventory.

Life cycle analysis does not define or explain actual environmental effect, for example, a life cycle analysis will tell us how many grammes of limestone are used to make a bottle of mineral water and how much energy was used to extract it. However, it does not tell us the environmental impact of this action, such as whether limestone is a scarce resource or whether its extraction causes pollution.

Life cycle analysis serves to address issues such as:

what are the life-cycle impacts generated by a product or process and how do different products or processes compare?

the assessment of process efficiencies for a given output - the calculation of energy and material usage efficiencies within a given economic sector or activity and the identification of areas for improvement.

4.2 Principles and Techniques of Life Cycle Analysis.

An environmental footprint is the term used when referring to the impacts of a product or service. For example, a life cycle analysis may be used to determine the different packaging options that can be provided for a litre of milk, in a carton, glass bottle, plastic, or cardboard carton.

There are four phases in conducting a life cycle analysis which are as follows:

1. goal and scope definition; 2. life cycle inventory (LCI) analysis; 3. life cycle impact assessment; 4. interpretation.

4.2.1 Goal & Scope Definition.

It is important that there a clear definition of the goal and scope at the beginning of the assessment. This ensures that the information collected throughout the assessment remains relevant. This depends on the reasons why the organisation wants to undertake the assessment and what they want from the exercise. This can be simple or complicated. They can be focussed on key issues such as the global warming potential of the system or detailed and comprehensive, looking at the inputs right through to the breakdown and analysis of each stage.

The definition of the goal depends on the following factors:

The intended application of the life cycle analysis. The reason for conducting it and the intended audience. What specific decisions the life cycle analysis will be used to assist.

The scope must be linked with the goal and should define the breadth and depth of the assessment needed to address the goal. The scope should include:

Definition of the function of the system being investigated, including the functional unit.

Definition of the system boundaries. Methods of gathering the data. Key assumptions and limitations.

So, the first step in life cycle analysis is to define what needs to be done, and early attempts at LCA failed through not defining the system boundary. When the boundaries are defined, the ''cradle to the grave'' analysis requires that each input in each process is traced back to resources taken from the environment, while outputs are followed to the final release into the environment. Effectively, a flow chart is produced.

4.2.2. Life Cycle Inventory Analysis.

Inventory analysis involves the compilation and quantification of the material, energy and waste flows (environmental aspects).

The inventory stage is the process of identifying the energy, raw materials and wastes generated in the production, distribution, use and disposal of the material, energy or waste.

It maps the system stages and the inputs and outputs in accordance with the goal and scope.

The data on the materials can either be 'situation specific' or generic.

Once obtained, the data need to be expressed in terms of the unit flow or product through each stage of the system and, ultimately, to the functional unit.

4.2.3 Impact Assessment.

This phase aims to evaluate the significance of environmental impacts using the results of the life cycle analysis.

Impact Categories (classification)

A key step in impact assessment is the selection of impact categories. These might include global climate change, acidification, air quality, stratospheric ozone depletion, biological oxygen demand (BOD), eutrophication, toxicity of substances and resource depletion.

Characterisation

This step applies numeric 'indicators' related to the impact category, e.g. they exist as ozone depletion potentials, photochemical ozone creation potentials and global warming potentials.

Valuation

This step is subjective as it attempts to give value to the data so that different impacts can be compared. This stage requires clear explanation of how the ranking or weighting scores are arrived at, so that the process is transparent.

4.2.4. Interpretation.

At this stage, the findings of the life cycle assessment are reviewed. They are checked to see if they are consistent and that the assumptions are sound. This must also be linked to the goal and the scope of the life cycle assessment and will identify priorities for improvement.

Another example..

Question 5.

Which phase of the Life Cycle Analysis involves the compilation and quantification of the environmental aspects?

Multiple Choice (HP)

Answer 1: Goal and scope definition

Response 1:

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Answer 2: Life cycle inventory analysis

Response 2:

Jump 2: Next page

Answer 3: Life cycle impact assessment

Response 3:

Jump 3: This page

Answer 4: Interpretation

Response 4:

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5.0 General Requirements for Risk Assessment.

Through the use of the environmental risk assessment management tool, available information on an environmental problem can be organised and analysed.

It has some aspects in common with other decision making tools, such as environmental impact assessment (EIA) and strategic environmental assessment (SEA). As risk assessment addresses probability and uncertainty it makes it ideally suited to distinguishing between adverse environmental impacts (or consequences) that could occur, and the likelihood (probability) of the impacts actually occurring.

Good corporate governance involves risk profiling across organisations and as we have seen, there are legal, moral and financial reasons for managing environmental risk. As a result, many large corporations have risk management committees that report periodically to the board and they have risk management systems that allow unacceptable risks to be managed.

The main objectives of risk assessment is to determine the measures required to comply with relevant, health, safety and environmental legislation.

A risk assessment comprises the following elements:

Hazard identification a hazard is the potential of any activity, process or substance to cause harm.

The risk is the likelihood of the hazard being realised. The severity of the consequences of the event.

5.1 Risk Assessment.

Once the information on the hazard, likelihood and severity of consequences are identified, a risk assessment can then be conducted.

A Risk Assessment Model

Risk assessments may be quantitative or qualitative.

A quantitative risk assessment, using numerical values, can be used to quantify the risk level in terms of the likelihood of an incident and its severity.

During a qualitative risk assessment a judgement is made as to whether the risk is probable in terms of high, medium, low or negligible. The consequences are calculated on a scale of

severe, moderate, mild or negligible. Please see the qualitative risk assessment model below.

Complex environmental issues with significant consequences will invariably require a combination of qualitative and quantitative analysis, usually because certain aspects of the system are better described than others.

Source: http://www.defra.gov.uk/environment/risk/eramguide/02.htm

Estimation of risk from consideration of magnitude, consequences and probabilities

Increasing acceptability

Consequences

Severe Moderate Mild Negligible

Probability

High high high medium/low near zero

Medium high medium low near zero

Low high/medium medium/low low near zero

Negligible high/medium/low medium/low low near zero

Once the risk assessment has been conducted, the next stage in the risk assessment is the control of the risk.

Environmental risk assessment is fundamental to all phases of development for waste management facilities, from the strategic planning level through to the regulation of an individual facility. At the strategic level, risk assessment informs decisions about land use and underpins assessment of the environmental impact associated with the site location considered, through the development planning process.

Risks from land contamination have historically been addressed on a suitable-for-use basis with most sites being assessed for their future use under the planning regime. With the introduction of Part IIA of the Environmental Protection Act 1990 the contaminated land regime in 2000 and the Contaminated Land Regulations in 2006, an increased awareness by regulators and industry of the risks posed by land based on its current use has developed.

Under the Control of Major Accident Hazards (Amendment) Regulations (COMAH) 2005, there is a fundamental requirement for operators to undertake an environmental risk assessment in a systematic way and to clearly demonstrate that risks have been identified and all necessary measures put in place to prevent major accidents and to limit their consequences if they do occur.

5.2 The Control of Major Accident Hazards (Amendment) Regulations (COMAH) 2005.

Introduction

The Control of Major Accident Hazards Regulations (COMAH) implement the Seveso 11 Directive except for land-use planning requirements which are implemented by changes to planning legislation. They replace the Control of Industrial Major Accident Hazards Regulations 1984 (CIMAH) and came into force in April 1999. Amendments were made to those regulations in 2005.

The COMAH Regulations require operators of major hazard establishments to take all measures necessary to prevent major accidents and limit their consequences to persons and the environment. Major accident establishments are those which involve dangerous substances such as toxic chemicals e.g. arsenic pentoxide, liquefied petroleum gas, chlorine and explosives in their operations.

Plant failure or human error can lead to the uncontrolled escape of pollutants into the environment, in the form of spills, leaks and releases leading to fire and explosion. Due to their unplanned nature they are difficult to control as the following cases illustrate:

5.3 Learning from Past Incidents.

Flixborough (Nypro UK ) Explosion 1st June 1974

Summary

Rupture of bypass system resulted in the escape of a large quantity of cyclohexane gas.

The cyclohexane formed a flammable mixture and subsequently found a source of ignition.

Site severly damaged by the resulting unconfined vapour cloud explosoin. 28 people killed - eighteen of these fatalities occurred in the control room as a result

of the windows shattering and the collapse of the roof. 36 people onsite and 53 people offsite were injured. Extensive injuries and damage to 1,821 houses and 167 shops and factories. Insurance costs 500 Million (2000 prices). Plant rebuilt but closed down after a few years for commercial reasons. Brought to public awareness the hazards presented by major chemical sites.

Seveso 1976

Reactor had gone out of control, overheating caused safety value to open. The high temperature caused an unusually high quantity of the by-product TCDD

(2,3,7,8,-tetrachloro-dibenzo-p-dioxin) to