Odour Guidance Internal Guidance for the Regulation of Odour v3 - EA England Wales - 2002

8/14/2019 Odour Guidance Internal Guidance for the Regulation of Odour v3 - EA England Wales - 2002

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ENVIRONMENT AGENCY

ODOUR GUIDANCE

Internal Guidance for the Regulation of Odour

at Waste Management Facilities

July 2002

VERSION 3.0

(Amended following external consultation)

Not to be applied directly to any existing permit or registered application but may be

used to identify issues and promote consistent resolution.

Note: This document constitutes guidance issued by the Environment Agency to its regulation

officers.


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Odour Guidance for Waste Sites, Version 3.0, July 2002 1

This document has been produced in consultation with officers from different regions

and it is issued with the approval of the National Waste Group. It will be subject to

periodic review to reflect any developments in technical guidance which affect the

advice herein.

The Working Group consisted of:-

Keith Ashcroft North West Region

Brian Bone Midlands Region

Jan Gronow National Policy

Mark Harvey Southern Region

Nigel Kendrick Environment Agency Wales

Jonathan Lees South West Region

Chris Peters (Chair) Thames Region

Andrew Phillips Environment Agency WalesLorraine Powell EPNS

Carol Romero North West Region

Jim Scott North East Region

Dave Young (Lead Author) Anglian Region

William Edwards Thames Region


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CONTENTS

EXECUTIVE SUMMARY ............................................................................................................................ 4

1.0 OBJECTIVE.........................................................................................................................................6

2.0 INTRODUCTION.................................................................................................................................6

2.1 PREAMBLE ..........................................................................................................................................6

2.2 LEGAL BACKGROUND...........................................................................................................................6

2.3 GENERAL CONSIDERATIONS .................................................................................................................9

3.0 INFORMATION REQUIRED IN SUPPORT OF AN APPLICATION........................................... 10

4.0 LICENSING APPROACH .................................................................................................................11

5.0 INSPECTION AND MONITORING .................................................................................................13

6.0 ENFORCEMENT............................................................................................................................... 16

FIGURE 6.1 FLOW DIAGRAM INDICATING THOUGHT PROCESSES FOR ENFORCEMENT ACTION ...................19

7.0 HEALTH & SAFETY AND HEALTH..............................................................................................20

APPENDIX A - FACTORS CONTIBUTING TO ODOUR PROBLEMS FROM WASTE

MANAGEMENT FACILITIES .................................................................................................................. 21

TABLE A.1............................................................................................................................................... 22

APPENDIX B - PROCEDURE FOR CARRYING OUT AN ASSESSMENT OF ODOUR AT WASTE

MANAGEMENT FACILITIES .................................................................................................................. 27

B1 OBJECTIVE.......................................................................................................................................28

B2 PROCEDURES...................................................................................................................................28

B2.1 GENERAL .....................................................................................................................................28

B2.2 AT THE ASSESSMENT LOCATION....................................................................................................29

B2.3 HOW TO REPORT THE RESULTS .......................................................................................................30

B2.4 TRAINING AND CALIBRATION.........................................................................................................31

B3 ODOUR ASSESSMENT REPORT....................................................................................................32

B3.1 REPORT PRO-FORMA .....................................................................................................................32

B3.2 NOTES ON COMPLETING PROFORMA ..............................................................................................32B3.3 CLASSIFICATION SYSTEM FOR ODOUR PARAMETERS .......................................................................32

APPENDIX C - METEOROLOGICAL DATA.......................................................................................... 35

C1 GENERAL ..........................................................................................................................................36

C2 ATMOSPHERIC STABILITY ..........................................................................................................36

TABLE C2.1 ATMOSPHERIC STABILITY CATEGORIES....................................................................................37

TABLE C3 THE BEAUFORT WIND SCALE ....................................................................................................38

APPENDIX D - ODOUR DESCRIPTORS..................................................................................................39

TABLE D1 PLEASANT ODOUR DESCRIPTORS AND HEDONIC SCORE ......................................................41

TABLE D2 UNPLEASANT ODOUR DESCRIPTORS AND HEDONIC SCORE ..................................................42

TABLE D3 ODOUR DESCRIPTORS WITHOUT HEDONIC SCORE...................................................................43


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FIGURE D1 ODOUR WHEEL .........................................................................................................................44

APPENDIX E - UNDERSTANDING SMELL............................................................................................ 45

E1 REALISTIC EXPECTATIONS OF THE NOSE ..............................................................................................46

E2 ODOUR FATIGUE ................................................................................................................................47

INDEX.......................................................................................................................................................... 48


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EXECUTIVE SUMMARY

Wherever bulk quantities of waste are handled, kept, treated or disposed of there is potential

for the generation of offensive odours. Geology, economics, logistics (e.g. transport systems)

etc. often result in waste management facilities being situated close to residential, commercial,

industrial or amenity areas. It is reasonable that members of the public, going about theirnormal living, working or leisure activities, should expect not to be offended by odours arising

from these facilities.

The EC Framework Directive on Waste makes it a relevant objective to ensure that waste is

recovered or disposed of without harm to human health or pollution of the environment,

including without nuisance through noise or odour. The Framework Directive is transposed

into the UKs national legislation mainly through the Environmental Protection Act 1990 and

the Waste Management Licensing Regulations 1994. The control of odour from waste

management facilities will be within the remit of the Environment Agency and the planning

authority, where odour nuisance will be a material consideration in the determination of a

planning application. Conditions in the waste management licence should complement the

planning requirements for the site in order to avoid any unnecessary duplication of controls.

This document uses, for convention, the format of nuisance to refer to nuisance in respect

of relevant objectives under the EC Framework Directive and Nuisance to refer to Statutory

Nuisance in respect of the powers of Environmental Health Authorities.

The Agency has a duty to ensure that the deposit, recovery and disposal of controlled

waste does not take place in a manner likely to cause pollution of the environment or

harm to human health. As such, links must be maintained with other authorities such

as local authorities (in their role as planning and environmental health authorities) andthe Health and Safety Executive. Odour does present potential health issues, even if

only in perception, and it is therefore important to remember that the Agency does have

powers and duties to address human health issues in addition to pollution and amenity

issues.

The aim of this guidance is to provide Agency officers with the relevant background to this

issue and to put forward a nationally consistent approach to the control of odour through the

permitting system and the subsequent monitoring of any odours produced.

It proposes that:

all new licence applications are assessed with regard to odours via a riskassessment provided by the applicant or operator, bearing in mind that some sites

may have already provided odour assessments as part of their planning permission

process. This risk assessment will be used to define the approach to odour control

within the licence;

the impact of odour on the surrounding environment is considered as part ofroutine site inspections;

odour is primarily controlled at source by good operational practices, the correctuse and maintenance of plant and operator training;


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odour controls are considered in consultation with other relevant regulatoryauthorities.


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1.0 OBJECTIVE

1.1 The objective of this document is to provide guidance to Agency officers seeking tocontrol odours originating from licensed and exempt waste management facilities; to

suggest areas that need to be considered in setting licence conditions ; and to seek

national consistency in the monitoring of odours. In respect of the last item, AppendixB describes a scheme for subjective monitoring of odours around waste management

facilities. It is intended for use by EA officers, but could equally well be used by site

operators.

1.2 This guidance applies to landfill sites and other waste management activities thatfall under PPC regulations, until such time as sectors specific guidance becomes

available. For IPPC sites, reference must also be made to the Agencys IPPC

technical guidance on odour1.

2.0 INTRODUCTION

2.1 Preamble

2.1.1 A dictionary definition of odour gives:-

odour a) that characteristic property of a substance which makes it

perceptible to the sense of smell,

b) a smell whether pleasant or unpleasant; fragrance or stench.

2.1.2 The perceptibility of an odour depends on the concentration of that substance in theatmosphere. For each substance there is a limiting concentration in air below which

its odour is not perceptible. This is generally referred to as the odour threshold of that

substance. More information is available in the Agencys IPPC technical guidance note

on odour.

2.1.3 The subject of odour is a complex one.

An odour can arise from a single substance or from a combination of substances.

In combination with other substances, the characteristic odour of a single substancecan be modified so as to be unrecognisable.

Odour from a combination of substances changes as the mixture becomes dilutedand the concentration of each component falls below its odour threshold.

Odours from a substance or mixture of substances can be pleasant when dilute oroffensive when concentrated.

Odours that are pleasant or acceptable to one nose can be offensive to another.(See Appendix D)

People have different odour thresholds, so odours that are detected by one personmay not be detectable by another.

2.2 Legal background

1 EA, IPPC H4 Technical Guidance Note, Horizontal Guidance for Odour, Part 1 Regulation and Permitting(draft), Part 2 Odour Assessment and Control (draft)


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2.2.1 The following provides a brief overview of the legal background relating to the controlof odours from waste management facilities.

2.2.2 Activities involving the recovery or disposal of waste are subject to the requirements

of the Framework Directive on waste (Directive 75/442/EEC, as amended by Directive91/156/EEC). Article 4 of the Directive requires that member states ensure that waste

is recovered and disposed of without endangering human health and without using

processes or methods which could harm the environment, and in particular:

- without risk to water, air, soil and plants and animals- without causing a nuisance through noise or odours,- without adversely affecting the countryside or places of special interest.

The waste management licensing system established under Part II of the Environmental

Protection Act 1990, and the Waste Management Licensing Regulations 1994, is the

main means by which the Directives requirements have been transposed into nationallaw. The Environment Agency, under Section 35 of the Environmental Protection Act

1990 (EPA90), grants licences to waste management facilities on such terms and

subject to such conditions as appear to be appropriate to the activities to which the

licence relates. The purpose of the terms and conditions are to ensure that the activities

authorised do not cause pollution of the environment, harm to human health or become

seriously detrimental to the amenities of the locality. The Agency is required to

discharge their functions, including licensing, with regard to the relevant objectives of

the Framework Directive.

2.2.3 Harm is defined in Section 29 of EPA90 as including, in the case of man, offence to

any of his senses or harm to his property.

2.2.4 The 1994 Regulations state, in Schedule 4 Paragraph 4, that the relevant objectives,

transposed from the EC Framework Directive on Waste, in relation to the disposal and

recovery of waste include, inter alia, that processes do not cause nuisances through

odour.

2.2.5 Statutory guidance given in Waste Management Paper No. 4 (WMP4) indicates thatthe planning function and the licensing function should complement each other rather

than duplicating controls. The planning system controls the development and use of

land in the public interest, and WMP4 states that the prevention of nuisance is one ofthe important issues in determining the location of waste management facilities.

2.2.6 Many waste management facilities will be subject to an environmental impactassessment as part of this process. However, WMP4 states that planning controls are

not an appropriate means for the detailed control of pollution from waste management

facilities and that this should be done by the Agency, as Waste Regulation Authority,

through the licensing system to ensure that the relevant objectives are met.

2.2.7 Where planning permission (resulting from the taking of a specified action by a planningauthority before 30 April 1994) was granted after 1 May 1994, the waste management

licensing system should be used for imposing detailed controls to ensure the relevantobjectives are taken into account. For example, by requiring impact assessments at the


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licence application stage and through the life of the site until surrender of the licence,

routine monitoring frequencies and protocols, and remedial action to be taken in the event

of the appropriate standard not being achieved. Although the planning permission may

have been issued with regard to the relevant objectives, licence conditions should be

imposed that complement, rather than duplicate or overstep, the framework set by the

planning permission.

2.2.8 However, where the Agency is not satisfied that the relevant objectives are likely to be metwithin the framework of the planning conditions, a licence must still only be granted with

such conditions that appear to the waste regulation authority to be appropriate (Section

35(3) of the 1990 Act), regardless of the date of the planning permission.

2.2.9 It is, however, not permissible to reject an application for a licence on the grounds ofserious detriment if planning permission (resulting from the taking of a specified action

by a planning authority before 30 April 1994) was granted after 1 May 1994. There is

therefore a need for the Agency, as a statutory consultee, to communicate any concerns tothe planning authority; in particular on the basis of serious detriment to the amenities of the

locality to ensure that amenity will be adequately protected (thus achieving the relevant

objectives)

2.2.10 Where planning permission was granted before 1 May 1994 or where it is not required(Schedule 4, Section 9(7) of the 1994 Regulations), the Agency is under a duty to reject a

licence application on the grounds of serious detriment to the amenities of the locality.

Licence conditions need to be imposed to prevent serious detriment to the amenities of the

locality affected by the activities controlled by the licence.

2.2.11 As with noise, the control of odour is the responsibility of a number of authorities. Allproposed sites likely to produce odour areas should be discussed with and perhaps

inspected in conjunction with the local Environmental Health and Planning Officers.

2.2.12 Part III of the Environmental Protection Act, 1990 enables Environmental HealthOfficers to control any odour that is prejudicial to health or a nuisance that a waste

management facility might cause to a nearby community. In Scotland, however,

nuisance is dealt with principally under the Public Health (Scotland) Act, 1897.

2.2.13 WMP4 advises that licence conditions relating in a general way to Nuisance should

therefore be avoided. However, Section 29 of Environmental Protection Act, 1990defines the harm to human health aspect of the EC Framework Directive on Wastes

relevant objective of nuisance to include offence to any of mans senses. WMP4

further advises, therefore, that licence conditions that control harm in a specific way

must be included where necessary.

2.2.14 Planning Policy Guidance Note PPG23, at paragraph 3.23, advises Local PlanningAuthorities that a lack of confidence in the effectiveness of controls which may be

imposed under pollution control legislation is not a legitimate ground for the refusal of

a planning permission or for the imposition of conditions on a planning permission

which would merely duplicate such controls. PPG10, which replaces parts of PPG23,

has not changed this guidance.


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2.2.15 If odour from a site constitutes a Statutory Nuisance, an Abatement Notice may beserved by the Local Authority. This may require that the nuisance is stopped altogether

or restricted. Where a licence has been issued and the site operated within the

conditions of that licence, it does not mean that an Abatement Notice cannot be

served. The fact that licence conditions are being met does not constitute a defence

against odour Nuisance proceedings. Whether a Statutory Nuisance occurs willdepend on the interpretations of an Environmental Health Officer or the court.

2.2.16 The decision as to whether an odour constitutes a Statutory Nuisance is likely todepend somewhat on it being persistent, but the odours that cause the majority of

complaints are transitory. However, it follows that if Statutory Nuisance occurs, then

insufficient control has been exercised through the licensing procedures by the Agency,

since it has much greater scope under offence to mans senses.

2.2.17 There are waste management facilities with planning permission that are exempt from waste

management licensing. In such cases the relevant objectives must still be achieved, boththrough any planning permission and also by virtue of regulation 17(4) of the 1994

Regulations and the terms of the particular exemption.

2.2.18 Regulation 18 of the 1994 Regulations makes it an offence for an establishment orundertaking to carry on an exempt activity (as defined in Schedule 3 of the 1994

Regulations) without being registered with the appropriate registration authority, this being

the Agency in most cases. The registration authority has a duty to maintain a register of

such activities.

2.2.19 Although, the exempt activities form the self-regulation aspect of waste management,

the Agency has a duty to carry out periodic inspections of these activities. Where anexempt activity is being carried out in a manner not consistent with the relevant

objectives, it cannot continue to be exempt from licensing.

2.3 General considerations

2.3.1 Wherever waste is handled the potential for generation and escape of odour exists.

2.3.2 There is the view that waste management facilities should not cause odours. A recent

Scottish High Court ruling gave that a condition, which required that All emissions to

air from the process shall be free from offensive odours as perceived by an authorised

officer of the Agency, outside the process boundary, was a valid condition.

However, this related to an authorisation under Part I of EPA90 and it is currently not

clear how relevant this decision would be under Part II of EPA90 in respect of the

Waste Management Licensing Regulations under English law.

2.3.3 In an appeal decision relating to Waste Management Licence conditions, (Alco Waste

Management Limited vs. Environment Agency, February 1997), the Planning

Inspectorate gave a complementary (but not as absolute) view in that ... the operator

cannot guarantee that the treatment of waste shall be free from offensive odours. All

that can be required is that odours are controlled so as not to harm human health or

amenity off the site.


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2.3.4 The appeal decision reaches many other conclusions and the following is based on

those conclusions:-

2.3.4.1 The purpose of licensing is to ensure that the disposal of controlled waste

does not give rise to pollution of the environment, harm to human health, or

serious detriment to the amenities of the locality (Paragraph B10, WMP26B).Section 29 of EPA90 defines harm as including offence to any of mans senses

and this must include the sense of smell. This can be safeguarded through the

imposition of conditions on a waste management licence.

2.3.4.2 There may be the possibility that odours, and the causes of odours, from waste

management facilities could be a risk to human health via chemical or

microbiological toxicity, or by causing stress or precipitating asthma attacks.

This guidance paper considers only amenity issues. The potential harm to

human health aspect of landfill gas is being considered by the landfill gas Task

and Finish Group but it must be accepted that there are potential health risksfrom sources other than landfill gas.

2.3.4.3 Amenity is a subjective issue. Amongst a group of individuals, not all will

agree, but a consensus can emerge about what could reasonably be considered

as offensive smells. The objective of this guidance is to achieve national

consistency in the assessment of odours.

2.3.4.4 The identification and analysis of harm to an amenity is not something which

can be wholly defined only by employing scientific methods; it must include a

subjective assessment of prevailing conditions by those directly affected or by

experienced observers. The directly affected group, or target group, are thepeople who live, work or use amenities outside the site boundaries.

3.0 INFORMATION REQUIRED IN SUPPORT OF AN APPLICATION

3.1 As mentioned above, wherever waste is handled, the potential for the generation and

release of odour exists. Therefore, at all stages of the development of a waste

management facility, from planning through to post closure, an assessment of the

possible risks should be carried out by the operator.

3.2 The assessment should take into consideration potential sources of odour, what actions

can be taken or are planned to minimise or eliminate them, the proximity, direction and

sensitivity of likely receptors, other factors such as prevailing winds and weather

conditions and any other pathways which may exist. This may form part of an

Environmental Impact Assessment produced as part of the planning application.

3.3 Appendix A is intended as an aide memoire listing the potential sources of odour from

different types of waste management facility and options available to effect

minimisation or control where appropriate.

3.4 At the pre-application stage, the method statement or working plan should be able to

show that all aspects of potential odour generation and release have been consideredby the operator and addressed or rejected as inappropriate.


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3.5 The Agency also has an opportunity to comment at the planning stage as a statutory

consultee. For a waste management facility, the opportunity exists to comment on the

appropriate use of the land in question, with respect to nearby housing and other

developments. Where planning consent is given against advice, the Agency will have

a difficult task in applying the appropriate pollution controls due to the location of thesite.

3.6 It is important to recognise that sites which fall within the licensing exemption criteria

still need to comply with the relevant objectives, including not causing nuisance

through odour. Therefore should an exempt site cause such a problem that means it

does not comply with the relevant objectives, it will no longer meet the terms of the

exemption and becomes a licensable activity.

3.7 Equally, existing sites, where the licence exerts no odour controls need to be

considered for modification in this respect where necessary. See 5.16.

4.0 LICENSING APPROACH

4.1 WMP4 makes it clear that licence conditions must leave the licence holder in no doubtabout the standards to be met. The placing of a condition on a licence which, in itself,

specifically seeks prescriptively to limit or eliminate odour from a waste management

facility is not likely to be the most effective means of achieving such control.

Proactive means are required to achieve adequate and effective control of odours at

source by licence conditions which ensure good day-to-day site management of

operational activities on the site. This aspect is not covered by this guidance paper

but an idea of the scope of the issues which may be addressed can be obtained byreference to the tables contained in Appendix A.

4.2 However, it may ultimately become necessary to take prescriptive action with respect

to odours by the placement of licence conditions that specifically address such issues.

Areas which might need to be considered are:-

The provision and maintenance of measures to secure the minimisation of releaseof offensive odours under everyday circumstances and particularly when specified

operations are undertaken, which the operators risk assessment has shown are

likely to increase the risk of odour release , e.g.:-

excavation into waste;

removal of leachate monitoring chimney lids or leachate manhole covers;

extension of leachate monitoring chimneys;

removal of intermediate cover;

maintenance of gas abstraction system;

storage of wastes. Notification to the Agency when such actions are to be undertaken. The provision and maintenance of measures to contain or suppress any odours

released or generated.

The escape of offensive odours beyond the site boundary and the effect onsensitive receptors identified in the risk assessment.

The provision of an effective and approved odour monitoring regime.


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The requirement to report to the Agency incidents of odour either reported to theoperator or detected via a monitoring regime.

4.3 Licence conditions may specify what needs to be done or may require that proposed

actions to meet a desired objective are detailed and approved via the working plan and

guidance on this aspect should be sought by reference to the Agencys Library ofLicence Conditions.

2Some further discussion on what may need to be taken into

consideration is given below.

4.4 The provision and maintenance of measures to control odours may need to take into

consideration:-

how agreement on the provisions should be made - in accordance with conditions,in writing or via the working plan;

when the agreement should be reached - prior to the deposit of waste or by a setdate;

the restriction of a waste or wastes either likely to give rise to or shown to give rise

to odour problems;

methods of keeping, storing, handling, treating, placing, discharging such wastes;

method of sealing containers, chimneys, boreholes, chambers, tanks, pipes whichcontain wastes or derived materials likely to give rise to offensive odours;

methods of filtering, scrubbing emissions from chimneys, vents, extraction unitslikely to give rise to offensive odours.

4.5 It is important that the agreed measures be maintained or available on site for use

should an odour occur. It may be, should the agreed measures need to be used, that

they do not prove to be entirely effective in which case revision of what is agreed is

clearly necessary. If agreed measures are not maintained or available, this should be

viewed as a clear breach of licence conditions and if odour problems occur under such

circumstances this should be viewed as a serious breach of licence conditions.

4.6 Conditions seeking to control the detection of odours beyond the site boundary should

be dependent on the location of the nearest receptor of odours. It may be that a local

amenity such as a much visited local beauty spot or much used footpath is immediately

adjacent to the site boundary in which case a condition requiring no odours beyond the

site boundary should be justified. It may be, however, that the nearest receptor is a

residential development for example some 500 metres beyond the site boundary, in

which case the condition should be tempered accordingly. Consideration should alsobe given to the significance of highways adjacent to the site particularly if they provide

access to amenity, residential, commercial or industrial development.

4.7 It must also be recognised that weather conditions and the topography of the area will

affect the way in which odour is dispersed. For example, in certain circumstances, it is

possible for an odour, arising from a site, to rise above ground level and be carried

beyond the site boundary to become detectable again at some point beyond it. (See

Appendix C)

2Library of Licence Conditions and Working Plan Specifications Volume 1: Waste Management Licences, Edition 2,

Published 2 August 1999


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4.8 Any scheme designed to monitor for offensive odours should detail:-

the method of assessment to be employed

identification of personnel specified to carry out monitoring, paying particularattention to the possibility that actual site staff may suffer from odour fatigue due

to constant exposure to an odour. See also 5.6

details of guidance, instruction and training given to specified personnel

minimum frequency of monitoring

liaison with the Environment Agency

the period over which the monitoring shall take place

monitoring points on and off the site, and

record keeping.

4.9 It must be remembered that some waste management facilities and activities, exempt

from licensing, have the potential to cause odour. However, if such sites cannot meet

the relevant objective relating to odour, they become licensable.

5.0 INSPECTION AND MONITORING

5.1 The Agency has a duty to carry out appropriate periodic inspections of waste

management facilities. Statutory guidance on inspection frequency has been provided

in an amendment to WMP4, which requires inspection frequency to be determined by a

risk-based approach.

5.2 Under Section 34 of EPA90 there is a Duty of Care incumbent upon anyone who

handles waste to ensure that all necessary actions are taken to protect the environment

and human health. Bearing in mind the definition of harm in Section 29 of the Act

which includes offence to any of mans senses, it follows that the Duty of Care must

include protection from offensive odours.

5.3 Paragraph 4.34 of WMP4 advises there is an expectation that the licensee of a waste

management facility should carry out its own environmental monitoring which, again,

in view of the definitions given in Section 29 of EPA90 should include monitoring the

air for offensive smells. It should be part of the operators responsibility to carry out

such monitoring.

5.4 To deal with the problem effectively, it is necessary for the operator to have a number

of things in place:-

sufficient day-to-day control to minimise or contain any problems via frequent andregular full inspections of the site carried out by the licensee or his staff;

a scheme to monitor the extent of the odours and to detect when a problem hasarisen or is likely to occur;

techniques and equipment which are acknowledged as being effective need to be inplace or available to deal with incidents as they occur;

a requirement to take effective action in the event of offensive odours beingdetected.


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5.5 The level of action and monitoring required around a facility should be gauged in

accordance with the risk from that site. For example, sites accepting potentially

odorous wastes, some special waste streams or a high proportion of putrescible waste

can present a high degree of risk of odours and are likely to receive a relatively high

level of attention subject to their location relative to sensitive receptors. Conversely,

sites accepting inert wastes3 present a low risk of odour problems.

5.6 A scheme for the subjective monitoring of odours around waste management facilities

is suggested in Appendix B. The scheme is designed for Agency officers but would

easily be adaptable to the requirements placed on an operator and could therefore be

suggested as a model. In any such scheme, operators, in particular, should recognise

the possibility that staff associated with a site, which may have odour problems, could

suffer from odour fatigue, i.e. the inability to detect relevant odours due to constant

exposure to them. In such circumstances it may be prudent to use staff not directly

associated with the site. As with other forms of environmental monitoring, Agency

officers should also carry out audit monitoring to check the results reported by theoperator, but again officers should be aware of the possibility of odour fatigue

resulting from regular or constant exposure to such odours. The scheme suggests that

monitoring should be followed by site inspections.

5.7 In addition to monitoring of odours by the operator and Agency officers, complaintsabout odour voiced by the local community can, in themselves, be an effective form of

monitoring where problems are known to exist. Complaints should be encouraged by

providing or publicising a mechanism, such as the Agencys Freefone emergency

number, 0800 80 70 60, for the receipt of complaints. It should also be explained to

complainants that is important for them to continue to complain rather than become

apathetic if nothing seems to be happening, since that is often one of the only ways inwhich the Agency might be able to attach a scale to the problem. In this respect both

the number of complaints and the number of complainants are important and need to

be recorded and details passed to the operator. When a complaint is received the

following information should be recorded.

a) Name, address and telephone number of complainant(s)

b) Time complaint received

c) Location of odour if not at address above

d) Date(s) and time(s) to which complaint relates

e) Duration of odour(s) - when it started; is it there now?f) When did it cease?

g) Any description of odour

5.8 Complaints received should also be checked out by Agency inspectors and sitepersonnel whenever possible. Officers should note, however, that the temporal

variance of odours may mean that the odour has subsided or changed from the time the

complaint was received. It may be appropriate to leave a log or diary with the

complainant so that they can record incidents of odour. Details noted should include:

dates, times and duration that the odour was detected; where the odour was detected

3 Landfill directive definition no risk, cannot by definition give off odourous gases unless not inert


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(inside/outside?); a description of the odour; weather conditions when the odour was

detected.

5.9 Where a site is shown beyond all reasonable doubt to be the cause of odour problemsin a locality in terms of harm or detriment to the amenity, all relevant potential sources

of odours on the site should be identified and given attention. Not every potentialsource of odour on the site may be generating offensive odours at any one time, but all

should be addressed in view of their potential detriment to amenity. It might be

unacceptable to leave the installation of any necessary controls for a phased, longer

term programme as any identified detriment to amenity might remain until all potential

sources have been dealt with.

5.10 There may be other sources of offensive odours in the locality which should be takeninto account during any investigation and these too may need to be addressed by the

relevant authority. In such circumstances, a liaison should be maintained with the

Local Authority Environmental Health Officer, a request made to monitor these othersites and to record whether they are, or are not, causing odours. This is not an

argument, however, to ignore or delay implementing any necessary control of odours

from a waste management facility (WMF) once they have been positively identified.

The officer should also be aware, however, of the possibility of an odour from a WMF

being due to the disposal of an odorous waste arising from a nearby local source. The

assessment of the WMF will need to take into account such a source, and it may need

to be investigated separately.

5.11 It is also important to encourage the operator to form a liaison with the localcommunity and perhaps for the Agency to be involved in this liaison. This is likely to

give operators a better understanding of the intensity, scale and emotive nature of anyproblems arising from their site. It is also likely to better motivate the operator to

cure the problems and make them, perhaps, more accountable for the consequences of

their development and the controls they exercise upon it. By inclusion of regular site

visits within this liaison, it is possible also for the community to feel involved in the

improvement of the amenity in the locality where problems are seen to be being

overcome.

5.12 A strategy to monitor odours should be devised in consultation with the Agency andthe Local Authority EHO, such that evidence can be compared between the operators

records, those of the Agency and those of the local authority in the event of complaintsbeing raised about offensive odours in the area. As outlined in 5.6 above, it should be

borne in mind that reliable complaints, in themselves, are a form of monitoring.

5.13 Paragraph 2.5 of WMP4 advises that there should be no doubt about the standards tobe met. Where an odour is consistent and due to known, specific chemical(s) which

can readily be measured by instrumental means, e.g. hydrogen sulphide, limits can be

set, perhaps at odour threshold limits at the site boundary or at the nearest sensitive

receptor beyond the site boundary. However, under normal circumstances due to the

variability and complexity of odours there are seemingly no readily available scientific

measurable indicators or factors for odours which might be incorporated into any

control standards or licence conditions.


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5.14 Where there is difference of opinion based on the interpretation of subjectivemonitoring and likely source of odour, but an obvious problem exists, recourse can

then be made to other techniques such as olfactometry using odour panels or the

application of more specific and scientific techniques such as gas chromatography and

mass spectrometry to collect air samples to identify the offending source. It is not

currently within the intentions of this guidance to discuss these techniques since theyare more fully covered in other Agency documentation.

4

5.15 Subsequently, once the source producing or likely to produce detriment to theamenities of the locality or harm to mans senses has been identified, if generated by

waste management activities, all that may be required is an agreement, via the working

plan, changing inappropriate practices or stopping the acceptance of any offending

waste stream(s). Alternatively, should this agreement not be reached, EPA90 allows

for the modification of the conditions of a licence under Section 37 or the revocation

or suspension of a licence under Section 38 or Section 42 by the issue of appropriate

notices. The operator however has the right of appeal and under normal circumstancesthe requirements of such notices would be ineffective pending the outcome of such an

appeal.

5.16 If an appeal is considered likely it should not be unreasonable for the Agency to use theprovisions of Section 43(6) of EPA90 to ensure that necessary works be carried out as

soon as possible. Under these provisions, the requirements of such notices remain

effective during any appeal, provided that the notice includes a statement to the effect

that in the opinion of the Environment Agency the required action is necessary for the

purpose of preventing or, where that is not practicable, minimising pollution of the

environment or harm to human health, which includes offence to mans senses.

6.0 ENFORCEMENT

6.1 Notwithstanding anything in the discussion below, reference should be made to the

Agencys Enforcement and Prosecution Policy document.5

6.2 It goes without saying that enforcement action comes into its own when discussion,

negotiation and persuasion have failed. That does not mean to say that enforcement

action should not be started until the above have reached their conclusion as often

enforcement action can take time to proceed and in the meantime, amenity and human

health can remain affected. However, this approach requires a careful balance to

ensure that if prosecution is proceeding, there is compliance with all the requirements

of both the Criminal Procedure and Investigation Act, 1996 and the Police and

Criminal Evidence Act, 1984.

6.3 The course of enforcement action taken depends of course on the particular problem.

Figure 6.1 below attempts to set out some outline thought processes aimed at assisting

officers in deciding which course of action to take. It makes an initial assumption that

to Agency officers minds, it has been established that the Waste Management Facility

4

Odour assessment and control Guidance for Regulators and Industry In preparation5 Environment Agency Enforcement and Prosecution Policy and Guidance Version 2 published 30

September 1999


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(WMF) is the source of the problem and other, possible, nearby sources have been

eliminated. It is not intended to form definitive enforcement guidelines. That is not

within the intended scope of this paper.

6.4 Where the decision process has led to the conclusion that prosecution is the only

available option, the importance of accurate, factual statements from officers and, ifappropriate, those affected in the locality is essential.

6.5 Paragraphs 6.7 and 6.8 below give guidance on the aspects and detail which may or

need to be covered in such statements. It is important to remember that hearsay

evidence cannot be included in statements. If an officer visits a site as a result of

complaints from the locality, in reporting that visit as evidence his statement must state

that he went to the site as a result of information received. It must not state that he

received N complaints.

6.6 It is acceptable, however, to state that N telephone calls were received from localresidents and that statements from n residents are produced as evidence.

6.7 An officers statement should cover the following points:-

Name

Job

Qualifications, if relevant, e.g. chemist

Length of time doing job and/or related duties

Other relevant experience e.g. member of this expert group

Health, general and at the time to which the statement relates, e.g. cold, sinusitisetc.

Smoker?

Time and date of observations

Location of observations with respect to the site in question

Method of conducting observations,

Walking? Where?

Driving? Where? Windows, sunroof, vents open?

Observations on weather conditions, particularly wind speed and direction, but alsoother relevant meteorological conditions (see assessment form in section B3).

If possible, an indication of atmospheric stability (see C2).

Strength of odours - observations could relate to guidance in this documentprovided that the guidance is produced as evidence in the form of an exhibit

Was the site visited?

Conditions on the site?

Did observations on the site correlate to observations outside? In the officersopinion, are the odours the same.

If the statement is in relation to an odour assessment (as described in Appendix B),

reference should be made to the odour assessment report number (see section B3).

This report will then cover observations on meteorological conditions and strength of

odour.


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6.8 A residents statement should cover the following points:-

Name

Address

Length of time at that address

Occupation

Health, general and at the time to which the statement relates, e.g. cold, sinusitisetc.

Smoker?

Statement of the date(s), time(s) and duration of periods when the resident hasbeen affected by odours. If diary of odours kept, it should be produced in

evidence

Where were they affected by the odours? Inside (where, how) and/or outside(where, how)

Description of smell Weather conditions.


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Can the source ofodour from the

site be identified?

Does thelicence includea "BoundaryCondition"?

Modify licence under S 43(6)+ S 37 to include boundarycondition with statement ofwhy modification is needed

Compliance?Issue notice underS 42(5) requiring

complianceCompliance?

Issue notice underS 42(5) requiring


Is the problemcovered by a

licence condition?

Is the licenceconditionsufficient?

Can the licencebe modified to

address situation?

Issue notice underS 42(5) requiring


Modify licence under S 43(6)+ S 37 to include boundary

condition with statement ofwhy modification is needed

Compliance?Issue notice underS 42(5) requiring


What is scale of problem/breach?

Persistence, frequency,strength of odour, location and

density of receptors

NO

NO NO

NO

NO NO

Consider ActionSuspension or revocationof licence or prosecutionunder S 33(1)(b) or (c)

NO

NO

NO

NO NO

YES

YES

YES YES

YES

YES

YES YES

YES

YES

YES

Figure 6.1 Flow Diagram Indicating Thought Processes For Enforcement Action

Note: Diagram assumes it has been established, in the Agency Officers mind, that the Waste Management Facility is the source of the

odour problem off site. See section 6.3


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7.0 HEALTH & SAFETY AND HEALTH

7.1 While the above text draws attention to various health and Health and Safety issues, it is

important to remind officers of these issues:-

The health effects of landfill sites are being studied and will be reported on elsewhere in duecourse.

Officers should be aware of their own health and safety when carrying out odour monitoringaround waste management facilities. Inhalations should not be made directly over, or even

relatively close to unknown drums, leachate chimneys, gas wells etc.

Before visiting a site, officers must also refer to the Agencys Health & Safety ManagementProcedures Manual.

Where concerns are received from members of the public with respect to health or Health and

Safety issues, in addition to noting and dealing with the concern as appropriate, the person

should also be made aware of the other avenues open to them to address or mollify their

concerns if necessary, e.g. The Health & Safety Executive, the Local Authority Environmental

Health Department, their own GP.


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APPENDIX A - FACTORS CONTIBUTING TO ODOUR PROBLEMS FROM WASTE

MANAGEMENT FACILITIES


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TABLE A.1

Typeof

Site

Factors that may contribute to odourproblems

Comment / Options / Mitigating Actions

Disposal of Odorous WastesSheeting of vehicles and speed of covering of wastes. Review Working Plan procedures fordealing with malodorous wastes. Ultimately review nature and range of waste permitted

Disposal of sulphur bearing wastes.

In co-disposal landfill sites, the deposit of bulk quantities of sulphur bearing wastes, such asgypsum and plaster board, such that large, discrete deposits of sulphates occur should beavoided due to risk of formation of large quantities of H 2S by bacterial action and the resultantodour and health and safety problem. Small deposits at a controlled rate should not causeproblems provided normal controls are in place.

Fire on site: Accidentally startedReceipt of burning wastesMixing of incompatible wastes

Dig out, isolate, damp down (care may make matters worse), cover, call fire emergencyservices, etc.

Landfill Gas: Passive venting/ Vent trenchesIneffective collection systemInadequate collection systemFailure of collection system:

Pump failurePipework failure

General presumption against; consider active extraction and/or scrubbing using carbon, peat etc.Consider upgradingConsider extending

Effect repairs, planned maintenance, increase routine inspection by operatorEffect repairs, increase inspection frequency, increase routine inspection by operatorL

andfillSites

Flare system: Failure of flame

Poor flame / combustion:(Incorrect gas mixtureIncorrect temperatureLow residence time)

Height of flare stack

Automatic re-ignition or shutdown fitted?

For all factors - See guidance and recommendations in EA Landfill Gas guidance6

6 Technical Guidance for Landfill Gas Flaring in the UK


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TABLE A1 (contd.)

Leachate system:Septic leachate, high sulphide contentOpen leachate monitoring chimneysOdour release by aerationHigh surface area, uncovered

Treat empirically with H2O2, Ozone etc. Increased frequency of monitoring & reporting byoperatorConsider covering and attaching to scrubber or landfill gas flare systemConsider alternative treatmentsReduce area, cover

Operational activities / failures:Inadequate compactionLarge working face / areaWastes not buried quickly enoughUse of cover:

Type/Depth/Maintenance of old

Increase compaction rate

Reduce size / area. Location of deposits move tipping areaCover progressively

See guidance and recommendations in EA Landfill Cover Task & Finish Group output7

Excavations into old wastes:Excavation of trenchesDrilling of wellsSlow burial of excavated wastesOpen trenches

Prior information to Agency? Proactive Informative around locality and cover quicklyPrior information to Agency? Proactive informative around locality and cap quicklyBury immediatelyConsider covers & use of odour scrubbers

Use of odour counteractants or neutralisersCan be effective but often more offensive to people in the locality than waste odours due tofalse odour or unknown constituents (fear element). Should be used selectively and withcaution

Weather conditionsMany atmospheric conditions e.g. high pressure, calm, foggy, or inversion can exacerbate,prolong or increase the range of any odour present as a result of operational conditions on anysite. Consider phasing of tipping sequence in respect of prevailing wind and weather conditions

LandfillSites(co

ntd)

Location of site with respect to receptors Planning considerations - appropriate use of land? Effect of Topography

7 Review and Guidance on the Use of Landfill Cover Materials. Edition 1.0. May 2000


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TABLE A1 (contd.)

Composting of Odorous Wastes Review working plan procedures. Ultimately review nature and range of wastes accepted

Operational activities / failures:Monitoring of temperaturesWaste turning anaerobicTurning compost at required intervals

Height of windrows

Needs careful attention, operator responsibilityNeeds careful attention, see belowFundamental principle, important to maintain aerobic state by turning or introduction of air byother meansMaximum height - 2 metres

See EA guidance on Composting8

C

omposting

Facilities

Location of site in relation to proximity ofreceptors

Planning consideration - appropriate use of land. Consider requirement to enclose facility

Tra

nsferStations

Disposal of Odorous Wastes:

Residual wastes

Age of wastes

Ventilation

Opening of tankers, drums etc. for

inspection, sampling etc. Transfer ofwastes from drum to bulk

Nature of wastes

Attention to end of day cleanliness required in case of putrescible wastes

Household wastes already up to at least two / three weeks old on arrival. Process quickly

Doors that open only to allow passage of vehicles probable recipe for trouble without roof levelventilation. Roof level ventilation also likely to require scrubbers or filters which in themselveswill require regular inspection / maintenance

Can cause severe odour problems in locality. Should be carried out under negative pressure

situations with extraction and scrubbing

Consider review nature of wastes accepted

See also EA guidance on clinical waste facilities9

8 Technical Guidance on Composting Operations. V3.0, for external consultation.9 Technical Guidance on Licensing Clinical Waste Facilities


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TABLE A1 (contd.)

Blending: Incompatible wastesControl matter, need for attention to operational detail. Potential Duty of Care issue if wronginformation given

Neutralisation, redox, precipitation:Odour from incompatible wastes,unexpected reactions

Overheating

Odour collecting / treatment hoods over tanks/vents. Control matter, correct informationavailable? Wastes checking procedures? Potential Duty of Care issue if wrong informationgiven

Odour collecting / treatment hoods over tanks/vents. Process control matter. Correct

information about wastes available? Potential Duty of Care issue if wrong information given.Wastes checking procedures?

Treatm

entPlants.

Physical&Chemical

Location of site with respect to proximity of

receptorsPlanning consideration - appropriate use of land

Age of waste/Onset of anaerobic conditions Minimise storage period

Waste is Food and food processing wastes,including brewery wastes

Minimise quantity handled per load, minimise transit / storage time

Storage&

Transport

Transport of Wastes

The transport of wastes is not a licensing issue but since this activity has significant potential forthe creating of odour nuisance it is felt worthy of note that this is a potential Duty of Care issueor Harm to Human Health issue within the meaning of Section 29 EPA, but officers might beable to influence at source via liaison with the local authority in respect of odour at the source

site or by giving advice in respect of the timing of transportation and the route taken to thedisposal / recovery facility.


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28/53


APPENDIX B - PROCEDURE FOR CARRYING OUT AN ASSESSMENT OF ODOUR AT

WASTE MANAGEMENT FACILITIES


29/53


PROCEDURE FOR CARRYING OUT AN ASSESSMENT OF ODOUR FROM WASTE

MANAGEMENT FACILITIES BY AGENCY OFFICERS

B1 OBJECTIVE

B1.1 To provide a clearly written procedure for a consistent, albeit subjective, assessment of odours

around licensed waste management facilities.

B1.2 It is intended that this guidance lays down a framework of principles which can be applied

consistently. It is realised that there will be a need for local adaptation of monitoring

procedures according to conditions at the site in question, its location and local surroundings,

the nature of any complaints, and reporting procedures according to management arrangements

and resource availability.

B2 PROCEDURES

B2.1 General

B2.1.1 To carry out the assessment, the inspector uses his own sense of smell to try and detect odours,

which may arise from the site being assessed. Each inspector likely to be involved in carrying

out odour assessments should initially accompany a more experienced inspector on an

assessment to ensure that the nature and offensiveness of any odours detected are being

perceived similarly. In addition, two or more officers should occasionally carry out assessments

together to ensure that assessments continue to be carried out to the same perceptions. If an

inspector has a cold, sore throat, sinus trouble etc. they should not carry out the assessment.

B2.1.2 Assessments should be carried out both routinely and in response to specific complaints. In

addition assessment should be carried out which are targeted to weather conditions likely to lead

to adverse odour at identified receptors. To this end, each inspector involved in carrying out

odour assessments must have regard to the weather forecasts for the area, including wind

strength and direction, barometric pressure, rainfall, temperature and humidity.

B2.1.3 Specific attention to the following points of detail should be noted:-

The inspector should not smoke or consume strongly flavoured food or drink, including

coffee, for at least half an hour before the assessment is carried out.

The consumption of confectionery or soft drinks should be avoided immediately before

and during the assessment.

Scented toiletries, such as perfume/aftershave should not be applied immediately before

or during an assessment.

The vehicle used during the assessment should not contain any deodorisers.

B2.1.4 Any complaint or contact regarding odour should be recorded in the appropriate manner, be it

incident form, contact form, log book or diary and responded to in accordance with the targets

set in the Agencys Customer Charter. Section 5.7 indicates what, ideally, should be recorded

when a complaint is received. The licence holder should be informed when a complaint has

been received and should be aware, on a general basis, that an odour assessment is likely to beundertaken by an inspector on the day of receipt of the complaint, if practicable.


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B2.1.5 Where complaints are received on a regular basis, an odour assessment should be carried out on

each site visit and statistics of complaints received and odour assessments carried out should be

kept and maintained by those involved.

B2.2 At the Assessment Location

B2.2.1 The assessment involves the inspector walking, as far as access allows, from a point, at a

distance from the site, towards the site boundary (or onto the site itself) and then continuing on

away from the site again. Where the assessment is being carried out routinely, the starting point

should be down wind of the site, progressing towards the site boundary and then away from the

site in an up wind direction. Where the assessment is being carried out in response to a specific

complaint, the starting point will be the location from which the complaint was made. When

arriving to carry out an assessment, the inspector should not go straight to the site, but rather

to the intended starting point.

B2.2.2 In carrying out the assessment, the inspector should walk slowly and breathe normally. If odourcannot be detected in this way, the inspector should periodically stand still and inhale deeply.

(Note: If odour but can only be detected by inhaling deeply, the intensity should be noted as 2

(faint). If odour is detected while walking, the intensity should be recorded as at least 3 see

B3.3.1)

B2.2.3 At appropriate intervals, the intensity, extent, i.e. persistence, and a description of the odour,

together with the location from site boundary, should be recorded. In addition the sensitivity of

the location where the assessment is being made, with regard to receptors, should be noted (see

B3.3), as well as any external activities such as agricultural practices that could be the source of

the odour. The possibility that an odour may change with distance due to dilution effects should

be taken into consideration.

B2.2.4 Periodically, the odour assessment around sites considered to be sensitive should include fixed

location assessments. The inspectors responsible for the site should determine a number of

receptor-sensitive locations. These locations will be determined from analysis of existing data

and of complaints received.

B2.2.5 A fixed location assessment should incorporate measurements reported over a standard time

period, say 5 minutes per location. The intensity and extent can then be evaluated over a time

period. Either, the intensity and duration of odour should be measured each time odour is

perceived, or measurements should be made at fixed time intervals, over a 5 minute period every30 seconds would be the minimum requirement. For the latter method, a standard yes/no

response would be required as well as indication of intensity, but extent measurements would

not be necessary.

B2.2.6 On eventual arrival at the site the atmospheric conditions prevalent at the time, See Appendix

C, should be evaluated if possible and recorded against site-specific factors, such as the location

and nature of site activities and location of sensitive receptors. A compass and hand-held

anemometer would be useful but is not essential

B2.2.7 The appropriate part of the site boundary relative to wind direction or complaints should first be

walked to detect any odour. Once again the inspector should walk slowly and breath normally.When odour cannot be detected in this way, the inspector should again periodically stand still

and inhale deeply facing upwind. In this respect, a common sense approach should be taken


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and the inspector should not inhale deeply over any boreholes. Particular care should be taken

if any sulphidic (rotten eggs) odours are perceived.

B2.2.8 In order to determine the extent of the odour "plume in sensitive areas, it may become

necessary to carry out assessments away from the site at points perpendicular to the plume axis

and equidistant from the source. The results should be plotted onto an appropriate plan. Insome circumstances it may be difficult to conduct such a survey because of the lack of access to

land in the vicinity of the site.

B2.2.9 Following an odour assessment a site inspection should be carried out seeking to trace any

observed odour back to source and to evaluate any potential odour-producing activities or

locations. Appendices A and C may prove useful in the respect.

B2.3 How to report the results

B2.3.1 All observations should be noted on the odour assessment report, following the classificationsystem for odour parameters. Observations should be reported to a member of the sites

technically competent management following the inspection. A report form is suggested in

Section B3 of this appendix. However, this paper does not seek to impose yet another form on

Agency officers if there exists already adequate alternative means of recording necessary

information.

B2.3.2 The odour inspection report should be passed to the appropriate senior inspector for signing and

recording what further action is required, e.g. letter to licence holder requiring odour control or

enforcement of licence condition requiring no odours beyond site boundary. The result of the

odour assessment, and any action required, should be confirmed on the completed assessment

report and the impact of odour arising from the site should be discussed with the licence holderat regular liaison meetings.

B2.3.3 Consideration should be given to carrying out periodic VOC surveys with the licence holder at

sites where particular problems have been identified. The inspector should discuss this with his

Line Manager before approaching the licence holder. Sampling for analysis of odorous trace

gases should not be carried out routinely but may be considered if a significant odour problem is

being disputed by the licence holder or proving difficult to resolve.

B2.3.4 A spreadsheet file can be set up for storing odour assessments for identified sites and

responsibility for inputting collected data should lie with the primary inspector.

B2.3.5 Data should be input at least monthly, and sorted by date and location. Each inspector should

be trained in the use of all applicable input and output functions.

B2.3.6 A bar chart for intensity, extent and sensitivity can be set up for one location at each site. The

chart should be revised monthly, by altering the range, and output for appropriate locations

printed as required. Other graphical methods, including time-series XY plots, should be used as

required, for example, for discussion at liaison meetings or to evaluate changes in operational

practices.

B2.3.7 A rose diagram can set up to display wind direction for each site. This should be updated dailyand output printed on a monthly or quarterly basis, depending on the number of assessments

carried out.


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B2.3.8 Output for each site should be assessed at a frequency dependent on conditions encountered and

complaints received, but at no less than once per quarter.

B2.3.9 Odour assessments should be carried out at a frequency determined by the potential for odour to

cause a problem and number of complaints received, and this frequency should be reviewed bythe line manager, in consultation with Licensing Officer and the responsible Area Functional

Manager on a regular basis.

B2.4 Training and calibration

B2.4.1 All inspectors responsible for assessing odour should be trained in the use of this procedure.

B2.4.2 For each sensitive and high risk site, and at a frequency no less than twice a year, two inspectors

should carry out an odour assessment independently but simultaneously. The completed

assessment reports should then be sent to the responsible officer, to evaluate for consistency.Such exercises can be used to confirm how representative the odour assessments are.

B2.4.3 Consideration may also need to be given to evaluating the sensitivity of each inspectors sense

of smell using olfactometry methods.


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B3 ODOUR ASSESSMENT REPORT

B3.1 Report Pro-forma

B3.1.1 A suggested pro-forma for reporting the results of the Odour Assessment is shown on the

following pages.

B3.2 Notes on Completing Proforma

B3.2.1 To complete the entry on General Air Stability reference should be made to appendix C.

B3.2.2 The entry for General Air Quality should include whether or not the air quality is good,

average or poor as this may influence odour perception on the day.

B3.2.3 The entry for Ground Conditions should record whether the ground is wet as a result of recent

rainfall as this may influence odour dispersion.

B3.2.4 External Sources of Odour refers to activities, not associated with the waste management

facility being assessed, that could be a source of odour.

B3.2.5 For entries on Odour Intensity, Odour Extent and Location Sensitivity, the classification

system presented in B3.3 below should be used.

B3.3 Classification System for odour Parameters

B3.3.1 Intensity

1 No detectable odour

2 Faint odour (barely detectable, need to stand still and inhale facing into the wind)

3 Moderate odour (odour easily detected while walking and breathing normally,

possibly offensive)

4 Strong odour (bearable, but offensive odour - will my clothes/hair smell?)

5 Very strong odour (this is when you really wish you were somewhere else)

B3.3.2 Extent (assuming odour detectable, if not then 0)

1 Local and impersistent (only detected during brief periods when wind drops or blows)

2 Impersistent as above, but detected away from site boundary3 Persistent, but fairly localised

4 Persistent and pervasive up to 50 m from site boundary

5 Persistent and widespread (odour detected >50 m from site boundary)

B3.3.3 Sensitivity of Location where Odour Detected

(assuming detectable, if not then 0)

1 Remote (no housing, commercial/industrial premises or public area within 500 m)

2 Low sensitivity (no housing, etc. within 100 m of area affected by odour)

3 Moderate sensitivity (housing, etc. within 100 m of area affected by odour)4 High sensitivity (housing, etc. within area affected by odour)

5 Extra sensitive (complaints arising from residents within area affected by odour)


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ODOUR ASSESSMENT REPORT FILE NO.

Site Assessment Date

Assessment Start Time Assessment Finish Time

Complaint Received Yes/No Date

Location of Complaint

Area

Grid Reference (where

location is not a property)

Weather Wind (strength and

direction)

Temperature

(deg. C)

Bar Pressure

(mbar)

(rising/falling)

% Cloud Cover General Air Stability

(see appendix C)

General Air Quality Ground Condition

Enter results of assessment overleaf

Plan attached showing location and extent of odour Yes/No

Additional comments

Action required

Reported to on site :

Signature :


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ODOUR ASSESSMENT REPORT contd.

Location Odour

Intensity

Odour

Extent

Location

Sensitivity

Odour Description External sources of odour Waste sources of odour

Odour Intensity Odour Extent (assuming odour detectable, if not then 0)1 -No detectable odour 1 -Local and impersistent (only detected during brief periods when wind drops or blows)

2 -Faint odour (barely detectable, need to stand still and inhale facing into the wind) 2 -Impersistent as above, but detected away from site boundary3 -Moderate odour (odour easily detected while walking and breathing normally, possibly offensive) 3 -Persistent, but fairly localised

4 -Strong odour (bearable, but offensive odour - will my clothes/hair smell?) 4 -Persistent and pervasive up to 50 m from site boundary

5 -Very st rong odour (this is when you real ly wish you were somewhere else) 5 -Persistent and widespread (odour detected >50 m from site boundary)

Location Sensitivity (assuming detectable, if not then 0)1 -Remote (no housing, commercial/industrial premises or public area within 500 m)

2 -Low sensitivity (no housing, etc. within 100 m of area affected by odour)

3 -Moderate sensitivity (housing, etc. within 100 m of area affected by odour)

4 -High sensitivity (housing, etc. within area affected by odour)

5 -Extra sensitive (complaints arising from residents within area affected by odour)


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APPENDIX C - METEOROLOGICAL DATA


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METEOROLOGICAL DATA

C1 GENERAL

C1.1 This appendix is included as general guidance since it is useful, and usually necessary, to takeaccount of meteorological conditions in determining causes and patterns of odour problems,

where they exist. The transport of pollutants from the source to receptor are affected by

meteorological variables, or state of the atmosphere in terms of; wind speed and direction;

insolation (amount of sunlight); lapse rate (temperature variation with height); mixing depth, and

precipitation. The non-meteorological factors such as type and quantity of odorous substances,

topography and individual susceptibility must also be considered. It is not intended that full

meteorological monitoring should take place at every site.

C2 ATMOSPHERIC STABILITY

C2.1 When considering the dispersion of air pollution or odour plumes, it is convenient to classify thepossible states of the atmosphere into stability categories originally defined by Pasquill

10. An

assessment of the stability category should be made when odour monitoring as this describes the

potential for dispersion of odours from a source.

C2.2 Table C2.1 illustrates typical features of each category and the extent of dilution that may be

expected under different atmospheric conditions.

C2.3 Stability Categories range from A, the most unstable, though to G, the most stable.

Category A corresponds to the most unstable atmospheric conditions and results in thegreatest amount of plume spreading. Surface heating effects caused by direct sunlight act as

an extra source of turbulence over and above that caused by the wind.

Category D, a neutral category is one where the turbulence is generated entirely by thewind and the degree of mixing will be less than Category A.

Category F/G are stable categories which result in the least spreading of a plume as themechanical (wind induced) turbulence is suppressed in these conditions.

10

F Pasquill and F B Smith, Atmospheric Diffusion, Chichester, Ellis Horwood, 1983


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Table C2.1 Atmospheric Stability Categories

Category Stability Dispersion* Occurrence

(% time in

year)

Wind speed

km/h

Time of day Sunshine or cloud cover

A Very Unstable Very good

7 Mainly day time Moderate sunshine

D Neutral Moderate 45 to 60 7 to 29 Day or night Slight sunshine or overcast

E Stable Poor 5-10 7 to 18 Night time only Clear or overcast

F/G Very Stable Very poor 10


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Table C3 The Beaufort Wind Scale

Force Description Observation km/hour

0 Calm Smoke rises vertically < 1

1 Light air Direction of wind shown by smoke drift, but

not wind vanes 1 - 5

2 Light breeze Wind felt on face; leaves rustle, ordinary

vane moved by wind 6 - 11

3 Gentle breeze Leaves and small twigs in constant motion12 - 19

4 Moderate

breeze

Raises dust and loose paper; small branches

are moved 20 - 29

5 Fresh breeze Small trees in leaf begin to sway, small

branches are moved 30 - 39

6 Strong breeze Large branches in motion; umbrellas used

with difficulty 40 - 50

7 Near gale Whole trees in motion; inconvenience felt

when walking against wind 51 - 61

8 Gale Twigs break off trees; progress generally

impeded 62 - 74

9 Strong gale Slight structural damage occurs (chimney

pots and slates removed) 75 - 87

10 Storm Trees uprooted; considerable structural

damage occurs 88 - 101

C3.1 The above table provides a rough approximation of wind speed in the absence of an

anemometer. A rough idea of wind direction can be obtained by observation, e.g. of smoke

plumes if appropriate, and reference to OS maps.


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APPENDIX D - ODOUR DESCRIPTORS


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ODOUR DESCRIPTORS

D1.1 The following information is included principally for background interest but also as an aid to

officers in their own assessment of odours, particularly in establishing the source of odours other

than those from waste management facilities.

D1.2 As indicated in section 5.7, it is useful, when recording information from a complainant, to seek

their description of an odour that is offending them. Tables D1 and D2 are derived from

American research work11

on odour descriptors which also concludes, as suggested at 2.1.3 in

the main body of this document, that both pleasant and unpleasant odours may become

offensive.

D1.3 Table D1 lists odour descriptors generally found as pleasant in decreasing order of pleasantness

based on Hedonic scores allocated by 150 participants in the American research. Similarly,

Table D2 lists unpleasant odours in increasing odour of unpleasantness.

D1.4 Table D3 presents the same odour descriptors in alphabetical order so that their pleasant orunpleasant rating is not indicated and would not therefore influence the use of a particular

descriptor.

D1.5 Figure D1 presents an Odour Wheel which attempts to link recognised waste derived odours

with possible sources on waste management facilities.

11 Dravnieks A, Masurat T, Lamm R A, Hedonics of Odours and Odour Descriptors:, inJournal of the Air Pollution Control

Association, July 1984, Vol. 34 No. 7, pp 752-755


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Table D1 Pleasant Odour Descriptors and Hedonic Score

Description Hedonic

Score

Description Hedonic

Score

Description Hedonic

Score

Bakery (fresh bread) 3.53 Spicy 1.99 Eucalyptus 0.99Rose 3.08 Peanut butter 1.99 Laurel leaves 0.97

Strawberry 2.93 Perfumery 1.96 Soapy 0.96

Orange 2.86 Grapefruit 1.95 Woody, resinous 0.94

Floral 2.79 Coconut 1.93 Light 0.91

Chocolate 2.78 Nutty 1.92 Dill 0.87

Fruity, citrus 2.72 Clove 1.67 Warm 0.78

Violets 2.68 Cooked vegetables 1.58 Grainy (as grain) 0.63

Peach 2.67 Raisins 1.56 Geranium leaves 0.57

Apple 2.61 Cool, cooling 1.53 Beany 0.54

Pineapple 2.59 Aromatic 1.41 Mushroom 0.52

Vanilla 2.57 Tea leaves 1.40 Eggy (fresh eggs) 0.45

Cherry 2.55 Green pepper 1.39 Raw potato 0.26

Cinnamon 2.54 Celery 1.36 Musky 0.21

Fried chicken 2.53 Crushed grass 1.34 Black pepper 0.19

Fragrant 2.52 Hay 1.31 Cork 0.19

Lemon 2.50 Raw cucumber 1.30

Minty, peppermint 2.50 Leather 1.30

Popcorn 2.47 Seasoning (for meat) 1.27

Melon 2.41 Oak wood, cognac 1.23

Meaty (cooked, good) 2.34 Anise (liquorice) 1.21

Coffee 2.33 Bark, birch bark 1.18

Caramel 2.32 Soupy 1.13

Pear 2.26 Caraway 1.06

Maple syrup 2.26 Malty 1.05

Lavender 2.25 Incens

Documents

Odour Guidance Internal Guidance for the Regulation of Odour v3 - EA England Wales - 2002