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Managing Biowastes from Households in the UK: Applying Life-cycle Thinking in the Framework of Cost-benefit Analysis A Final Report for WRAP

May 2007

Prepared by:

Dr Dominic Hogg, Adrian Gibbs, Enzo Favoino and Marco Ricci

Approved by

Joe Papineschi

Contact Details

Eunomia Research & Consulting Ltd 1 Kings Court Little King Street Bristol BS1 4HW

Tel: +44 (0)117 9426678 Fax: +44 (0)117 9426679

Web: www.eunomia.co.uk

Acknowledgements

Our thanks to Linda Crichton and Julian Parfitt for their comments. Our thanks also to an anonymous reviewer for helpful comments on an early draft.

Disclaimer

Eunomia Research & Consulting has taken due care in the preparation of this report to ensure that all facts and analysis presented are as accurate as possible within the scope of the project. However no guarantee is provided in respect of the information presented, and Eunomia Research & Consulting is not responsible for decisions or actions taken on the basis of the content of this report.

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Foreword Local authorities in the UK are currently challenged by a range of, sometimes conflicting, targets and obligations for waste treatment. These include:

Recycling and composting targets, set as a percentage (by weight) of the total household waste stream;

Obligations under the Waste and Emissions Trading (WET) Act and associated Landfill Allowances Schemes (LAS) for dealing with biodegradable municipal waste (BMW);

A general desire to reduce waste arisings in line with the waste management hierarchy;

Pressure from residents to provide comprehensive and good quality recycling services; and

Pressure to restrain the impact of increasing waste management costs on the Council Tax.

In recent years the considerable contribution garden waste collections can make to recycling targets has led some authorities to introduce garden waste collections at kerbside. Such schemes tend to be popular with households. However, the evidence now shows that such schemes, while increasing recycling rates, can draw additional material into the waste management system, particularly where they are offered at no charge at the point of provision.

The method of accounting for landfill allowances also encourages authorities to collect as much organic waste for composting as possible since all of the waste diverted in this way is deducted from their assumed biodegradable waste fraction sent for landfill. Organic waste diverted to home composting, the lowest cost method of treatment, is currently treated much less favourably in the calculations. The dilemma for authorities who are concerned that they will not meet their Landfill Allowances is whether to invest in (free) garden waste collections at the risk of increasing their treatment costs and damaging home composting campaigns.

In England, Defra has signalled that it will undertake an operational review of LATS during 2007 and as part of this process will look again at the treatment of home composting. This will be informed by the outcomes of a consultation exercise being undertaken by WRAP and Defra. This consultation will involve the devolved administrations, the relevant local government associations and other local authority bodies such as LARAC.

Recognising some of these conflicting pressures on local authorities WRAP commissioned Eunomia Research & Consulting Ltd to undertake a major study of the costs and benefits, including monetised environmental costs and benefits, of different approaches to biowaste1 collection and management. The study has looked at management approaches including home composting, and includes options where no segregation of biowastes by householders occurs at all. The study

1 In this study, biowaste is taken to mean, in the main, garden waste and kitchen waste.

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has also included a review of policy related to the management of biowastes, and the way this might affect the decisions being taken by local authorities.

The report potentially acquires additional significance by virtue of the fact that the European Commission, in considering a Thematic Strategy on the Prevention and Recycling of Waste, has proposed not to continue negotiations for a Biowaste Directive (though in ongoing discussions on the Thematic Strategy, some Member States have argued that it should). Instead, the proposal for a Thematic Strategy proposes to apply life-cycle thinking to determine, within Member States, strategies for management of biowaste. The authors have used this approach in considering options for collecting and processing biowaste in the UK.

This Report suggests that local authorities should develop a longer term approach to biowaste management and in doing so should consider carefully:

The potential for integrating home composting alongside the collection system;

The nature of the collection system to be chosen, particularly if food waste is to be collected;

The choice of treatment for the collected biowaste. Open windrow composting is the lowest cost option but is not permissible for waste containing food (both cooked and uncooked). In-vessel composting systems are required for biowaste containing food. Anaerobic digestion (AD) appears to offer additional benefits to in-vessel composting for food waste (as indicated above) but to date has not been developed to any significant extent in the UK

A range of different scenarios for collecting and treating household waste are modelled. Key points which follow from the modelling are:

Where home composting is promoted intensively, local authorities will save money. There is a reduction in waste delivered to Household Waste Recycling Centres (HWRCs) and in the quantity collected through kerbside collections (where these are provided). Based on work by WRAP, on average, a household that stops composting at home is likely to send an additional 105kg per annum to HWRCs and will set out an additional 115kg per annum into the collection system.

Systems which include free or unconstrained garden waste collection services tend to be more costly than those which target food waste only. The key reason is that additional garden waste can be pulled into the formal waste management system.

The additional cost associated with adding food waste to an existing garden waste collection can be significant. This is because all the material must be treated in an in-vessel composting facility.

Where food waste is collected separately, the frequency of collection should be higher than for refuse. This approach has been shown to increase the capture of food waste. Systems where food waste is collected weekly and refuse fortnightly are likely to be the most cost-effective.

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Where food waste only is collected at kerbside, there is little difference in the cost between the systems in which:

- all the separately collected food waste is digested and HWRC garden waste is composted in windrows;

- all the separately collected food garden waste plus the required quantity of HWRC garden waste is composted at in-vessel systems

This is an important observation as traditionally local authorities have tended to view anaerobic digestion as an expensive alternative to composting options.

As the costs of residual waste management increase (i.e. disposal costs of >70/tonne), the incremental costs of collection systems become less important in deciding the best value system for managing biowaste.

In summary, the report concludes that a sound management strategy for household biowaste is likely to include:

Intensive promotion of home composting as a means of diverting appropriate biowastes from landfill at the lowest cost;

Where kerbside garden waste collection services are provided they should be designed so as minimise the potential for attracting additional waste into the collection system. A number of measure are available to local authorities;

Separate collection of food wastes using efficient and lower-cost approaches so as to allow weekly collections at acceptable cost.

Provision of containers (kitchen caddies and kerbside containers) to make the separation of food waste easy for residents and to encourage them to take part in the service; and

Close consideration to matching the method of collection to the treatment system being operated. AD and in-vessel composting could both be valuable with AD bringing the higher environmental benefits.

The results of this study along with the outcomes of another study undertaken by Eunomia Research & Consulting for WRAP which examines in more detail the options available for the management of food waste 2 are summarised in a separate standalone report prepared by WRAP and available on the WRAP website3.

2 Dealing with Food Waste in the UK. Eunomia Research & Consulting report for WRAP, March 2007. www.wrap.org.uk/biowaste 3 http://www.wrap.org.uk/biowaste

Contents 1.0 INTRODUCTION.......................................................................................................1

1.1 Approach to the Work ........................................................................................ 1 1.1.1 Key Objective ............................................................................................... 1

2.0 INTRODUCTORY DISCUSSION..............................................................................4 2.1 Biowaste Streams .............................................................................................. 4

2.1.1 Garden Waste .............................................................................................. 4 2.1.2 Kitchen Waste.............................................................................................. 5 2.1.3 Other Biowastes .......................................................................................... 6

2.2 Kerbside Garden Waste Collections ................................................................. 7 2.2.1 Effect of Free Garden Waste Collections on Quantities Collected........... 7

2.3 Charging for Garden Waste Collections..........................................................13 2.3.1 Effects on HWRC Collections ....................................................................15 2.3.2 System Considerations .............................................................................20

2.4 Findings from the WRAP Home Composting Research .................................22 2.5 Summary...........................................................................................................22

3.0 THE POLICY CONTEXT ....................................................................................... 25 3.1 The UK ABPR and Recycling Targets...............................................................25

3.1.1 Regulating Animal By-products ................................................................25 3.1.2 The Effect of Recycling Targets (based on % by weight) ........................26

3.2 Waste and Emissions Trading Act ...................................................................27 3.2.1 Landfill Allowances & Trading Scheme (England) Regulations 2004...27

3.3 Biowaste Directive / Thematic Strategy for Soil Protection ..........................30 3.4 Summary...........................................................................................................31

4.0 LITERATURE REVIEW......................................................................................... 33 4.1 Comparative Life-cycle Studies .......................................................................33

4.1.1 Edelmann and Schleiss.............................................................................34 4.1.2 Vogt et al ....................................................................................................37

4.2 Cost-benefit Studies.........................................................................................44 4.2.1 Hogg et al ...................................................................................................44 4.2.2 Sundqvist et al ...........................................................................................46 4.2.3 Danish EPA.................................................................................................52 4.2.4 Nolan-ITU....................................................................................................57

4.3 Other Relevant Studies ....................................................................................60 5.0 APPROACH IN THIS STUDY ............................................................................... 61

5.1 Life Cycle Assessment and Cost Benefit Analysis..........................................61 5.2 Approach in this study......................................................................................62

6.0 COLLECTION SCENARIOS.................................................................................. 64 6.1 Collection Systems ...........................................................................................65

6.1.1 Area with Garden Size > 200m2...............................................................65 6.1.2 Area with Garden Size < 200m2...............................................................68

6.1.3 Scenarios for Both Garden Sizes with Kerbside Sort Of Recyclables....69 6.2 Mass Flows .......................................................................................................71

6.2.1 Per Household Quantities .........................................................................71 6.2.2 Composition ...............................................................................................71 6.2.3 > 200m2 Systems......................................................................................73 6.2.4 200m2 ............................................ 111

9.6 Full Results .................................................................................................... 117 9.6.1 Low Disposal Cost Results..................................................................... 117 9.6.2 High Disposal Cost Results.................................................................... 122 9.6.3 Incineration Disposal Cost Results ....................................................... 125

10.0 EXTERNAL COSTS OF TREATMENTS ........................................................... 129 10.1 Introduction ................................................................................................ 129

10.1.1 CSERGE et al (1993)........................................................................... 130 10.1.2 HM Customs & Excise......................................................................... 134

10.2 This Study ................................................................................................... 141 10.2.1 Landfill Scenarios................................................................................ 143 10.2.2 Incinerator Scenario ........................................................................... 144 10.2.3 Recovery of Energy ............................................................................. 144

10.3 External Costs for the Modelled Scenarios .............................................. 144 10.3.1 Omissions from the Analysis .............................................................. 144 10.3.2 > Scenarios, Disposal to Well Behaved Landfill ............................... 147 10.3.3 > Scenarios, Disposal to Less Well-Behaved Landfill....................... 151 10.3.4 > Scenarios, Disposal to Incinerator ................................................. 155 10.3.5 < Scenarios, Disposal to Well Behaved Landfill ............................... 158 10.3.6 < Scenarios, Disposal to Less Well Behaved Landfill....................... 160 10.3.7 < Scenarios, Disposal to Incinerator ................................................. 161

10.4 Summary .................................................................................................... 162 11.0 PUTTING IT ALL TOGETHER ......................................................................... 164

11.1 Total Social (Private + External) Costs...................................................... 164 11.2 Disposal to Landfill, High Gas Capture..................................................... 165 11.3 Disposal to Landfill, Low Gas Capture...................................................... 168 11.4 Disposal to Incinerator .............................................................................. 171 11.5 Summary .................................................................................................... 172

12.0 CONCLUSIONS & RECOMMENDATIONS ..................................................... 174 12.1 Conclusions ................................................................................................ 174 12.2 Recommendations..................................................................................... 177

12.2.1 WRAP.................................................................................................... 177 12.2.2 Defra / Environment Agency.............................................................. 178 12.2.3 Local Authorities ................................................................................. 179

12.3 Suggestions for Further Research ............................................................ 179 13.0 REFERENCES ............................................................................................... 181

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1.0 INTRODUCTION

Eunomia Research & Consulting was tasked by WRAP with carrying out a review of different approaches to managing biowastes in the UK. The emphasis of the research is on the application of life-cycle thinking, within the framework of cost benefit analysis, to understand how best to manage biowastes. In this sense, the document can be seen in part as informing the UKs position on the management of biowastes in the light of the proposals from the European Commission for a Thematic Strategy on the Prevention and Recycling of Waste.4

As a result of the Cabinet Office review of the Waste Strategy in 2002, and in the context of the establishment of the Waste Implementation Programme, WRAP was given a target to increase the number of households engaged in home composting. In addition to this, WRAP has been developing a programme for the management of biowastes, and in particular, the development of markets for composts. To this end, WRAPs Organics Programme runs workshops looking at good practice in a range of activities related to the management of biowastes, including process management and product marketing. WRAP also runs a programme of training for local authority officers involved in waste collection and recycling, and provides an advisory service to local authorities on recycling and composting (ROTATE). This range of activities raises the question as to how best to coordinate the various themes which different WRAP programmes seek to address, and how to ensure that the different activities supported by WRAP are mutually supportive.

This work aims to contribute to the process of developing a rational system for the management of biowastes. It also seeks to highlight some key issues which ought to be addressed by local authorities when they are considering how best to manage biowastes. It also discusses the policy implications, for WRAP and for government more generally, of seeking to achieve such an optimal situation.

1.1 Approach to the Work 1.1.1 Key Objective The key objective of this work is to critically review the options for the management of municipal kitchen and garden waste from households in the UK through the application of life-cycle thinking within a cost-benefit analysis framework. The Thematic Strategy on the Prevention and Recycling of Waste states:

Another important step will be to define, in consultation with the scientific and stakeholder community, basic guidelines to make life-cycle tools easily usable in waste policymaking, with an agreed approach and methodology. The aim is to make these tools easier to use in policy decisions from local to European level.

4 European Commission (2005) Taking Sustainable Use of Resources Forward: A Thematic Strategy On The Prevention and Recycling of Waste, Communication From The Commission To The Council, The European Parliament, The European Economic And Social Committee And The Committee Of The Regions, Brussels, 21.12.2005.

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The analysis includes segregated and un-segregated collect and treat options as well as home composting. The intention is that the work should assist in helping to formulate a WRAP strategy for different fractions of household kitchen and garden waste and to act as guidance for ROTATE contractors and local authorities.

By way of background, Section 2, introduces the subject matter. It highlights some of the key issues arising in the context of the discussion from an operational perspective.

Section 3 lists the key pieces of legislation which are of greatest significance to this study.

Relatively few cost benefit analyses of biowaste treatment systems have been undertaken, especially in the UK. Some BPEO analyses in the UK have, indirectly, incorporated elements of cost-benefit analysis by seeking to evaluate waste treatment systems by looking at cost, alongside several other parameters, of different treatment systems. A review and analysis of relevant life-cycle and cost-benefit studies is provided in Section 4.

Until now, most analyses involving life-cycle thinking have taken, as their functional unit, a tonne of waste. But for reasons which will be explained in Section 5, this approach can be misleading, since real world experience highlights the fact that households behave differently, and direct their waste to different fates, depending upon the collection (and treatment) system they are offered. In particular, the quantity of waste dealt with through different options is influenced by the collection system on offer. Consequently, an approach which takes, as its functional unit, a tonne of waste is starting from the erroneous assumption that the quantity of waste is unchanged by the collection method.

Because of this, the functional unit in this study is effectively the household (or a group of households), with the quantity of material dealt with within the system being allowed to vary with the nature of the collection system. Not only do quantities change, but so also does the composition of waste. Section 6, therefore, provides details of the collection scenarios being modelled, and the flows of waste material associated with them. These mass flows are important, as is the sub-composition of material, since they affect not only the performance of the biowaste treatments, but also the emissions from waste treatment facilities.

As the quantity and composition of waste collected changes, and because in some collection systems, components of the biowaste fraction are collected through different routes, the way in which these separate sub-streams are treated becomes important. This is made especially so in the context of the Animal By-products Regulation where, from the perspective of financial costs, there may be some merit in dealing with as much garden waste as possible through open-air windrow systems. The application of this logic is constrained by the requirement to ensure that in the case of composting systems, there is sufficient structural material to allow aerobic conditions to be maintained, and in the case of digestion systems, to ensure either that the process is sufficiently stable or that the C:N ratio is appropriate. Section 7 outlines the way in which specific treatment options might be chosen appropriately for each of the collection scenarios and discusses which treatment types might be best suited for which systems from the perspective of overall scheme optimisation.

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Estimates of the costs of the different treatment systems are made in Section 8.

Moving into the analysis phase, Section 9 looks at the private costs of the different systems proposed. In carrying out the modelling, an holistic approach to the costing of waste collection and treatment has been used. The modelling takes into account the implications of the mass flow modelling in the collection systems, and is also carried out against the backdrop of different treatment possibilities. The results of the modelling include an estimation of the effect of changing Landfill Allowances balances (this has been carried out separately from the modelling of the formal collection system for reasons described within Section 9).

Section 10 concentrates on the external costs and benefits of the systems being modelled. It starts with a review of work undertaken in the UK. It then looks at the external costs, these having been derived through developing life-cycle inventories and applying different damage costs associated with key pollutants to the emissions which result.

In Section 11, analysis is carried out on the total private and external costs and benefits (the social costs) of different approaches. It includes an analysis of total social costs.

Section 12 is the concluding section, and seeks to draw conclusions, and make recommendations, on the basis of the analysis undertaken.

Sections 8, 9 and 10 in particular are supported by a number of Appendices. These Appendices contain discussion of the data used in the analysis, as well as various caveats associated with the modelling.

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2.0 INTRODUCTORY DISCUSSION 2.1 Biowaste Streams The general question as to how best to collect biowastes as well as the specific question of how best to encourage home composting consistent with a well-designed collection system for biowaste, are questions of considerable importance to WRAP, and they have implications for WRAPs organics programme, for ROTATE (advising local authorities on collection), and for WRAPs work on waste reduction.

Biowaste generation in a given household can be considered as two separate, though in some households, related, systems for the generation of kitchen wastes and of garden wastes. Alongside this, other biowastes are also generated.

2.1.1 Garden Waste The generation of garden wastes might typically be associated with, amongst other things:

Size of garden and its nature (i.e. how much is planted to lawn, bedding, pot plants, shrubs, etc.);

The types of plants grown (fast, or slow growing);

The weather in a given year (affecting plant growth); and

How tidy the gardener keeps the garden.

In countries with a temperate climate, such as that experienced in the UK, garden waste arisings tend to be highly seasonal. The seasonality is itself an issue of some significance for collection and treatment systems.

The range of management routes includes legal and illegal ones. For example:

Home composting (taken to include leaf mould, any worm bins etc.);

Grass cycling (where clippings are left on the lawn) and grass mulching (where clippings are used on flower beds);

Household waste recycling centres or civic amenity sites (referred to as HWRCs in this report), where the material may be deposited in garden waste skips, or general skips, depending upon how well the site is managed;

A biowaste bin or sack (where this accepts garden waste);

Refuse collection (systems may or may not attempt to exclude garden wastes. In some systems, residents are asked to pay for sacks for garden waste collection, and this is co-collected with refuse);

Fly-tipping; and

Garden bonfires.

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These options are shown below.

Figure 1: Factors Influencing Production of, and Fate of Garden Wastes

This is a dynamic system. Peoples behaviour in terms of generation of waste can be, and is, affected by the collection system available to them. Their choice of management route is also affected by the collection system available to them. The consequence of this is that the oft-cited statement of local authority waste managers that little can be done to influence waste arisings is simply untrue where biowaste is concerned, especially where what is being considered is collected waste.

2.1.2 Kitchen Waste With kitchen waste, the issues are slightly different. Whereas garden waste generation presumes the existence of a garden, or at very least, some plants, all households are likely to generate some kitchen wastes. The generation of kitchen wastes includes both uncooked and cooked food materials. The size of the household, as well as lifestyle, and issues affecting the time available to prepare meals, are likely to affect the magnitude of kitchen waste arisings. The time which is available for / spent on cooking meals as opposed to eating out / buying pre-cooked meals is likely to have some influence on kitchen waste arisings. Ethnicity may also be an important factor since cultural norms may influence the likelihood of meals being home-prepared.

Kitchen wastes can be managed in similar ways to garden wastes. However, some options are less likely (such as HWRCs) whereas others are less likely for certain

GARDEN WASTE

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Weather?

How Tidy?

Home Compost?

HWRC?

Nature and Size of Garden?

Biobin?

Grass-cycling? Refuse?

Fly-tipping? Bonfires?

Collected WasteProblem Waste

WASTES TO BE MANAGED BY LA

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types of household (such as home composting in households with no garden, though worm bins may be a possibility in these situations). Some kitchen wastes may, despite the questionable legality of this, be fed to animals (it is difficult, after all, to see how the law on this could be enforced, and whilst the UK ABPR may affect every house in the land in principle, in practice, knowledge of it tends to be restricted to specialists and enforcement is likely to be problematic).

Figure 2: Factors Influencing Production of, and Fate of Kitchen Wastes

2.1.3 Other Biowastes There are a range of biowastes which do not fall readily under the heading of either garden waste, or kitchen waste. They include, for example:

Faeces from pets, including some materials used as cat litter;

Faeces from humans;

Residues from carpet cleaning;

Wood; and

Corks.

These materials are all, in principle, compostable and / or digestable, some being more easily dealt with in one or other treatment than others. Wood, depending

KITCHEN WASTE

Lifestyle / Education

Ethnicity?

Time Available for Food Prep

Home Compost?

Fed to Animals?

Size of Household?

Biobin?

Fly Tipped?

Refuse?

Collected WasteProblem Waste

WASTES TO BE MANAGED BY LA

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upon the form in which it arises may be better dealt with through other treatments, whilst human faeces do not normally arise in household waste unless where associated with nappy usage.

Other materials not normally considered as biowaste, but which are readily dealt with through some biological treatments, include cardboard. This is already collected in some schemes for composting, whilst on the continent, a number of schemes collect cardboard, including soiled materials such as pizza boxes, for anaerobic digestion. Cardboard is particularly useful in this latter respect as it is a source of biogas.

Finally, in the context of many waste composition analyses, it is worth pointing out that the category described as fines can often consist of large proportions of biowaste. As the left-over fraction in waste composition analysis, it is also the fraction where many food left-overs can be found. The significance of this observation depends partly upon the screen size used to separate the fines fraction after the rest of the material has been sorted. According to the different approaches to analysing waste components, the fines fraction tends to vary considerably. It is not unusual for 50% or so of the fines fraction to be putrescible material of one or other variety (so food waste might be underrepresented in some composition analyses).

2.2 Kerbside Garden Waste Collections The quantity of garden waste collected at the kerbside is likely to depend upon:

Housing structure (how many households have gardens, and of what size); Type of container for refuse (e.g., whether wheeled bin or sack, and if the

former, what capacity / choice of capacity); Prevailing policy on side waste (is side waste accepted or not?); Policy on garden waste and whether or not it is a charged service; Availability and proximity of HWRCs; Home composting activity and the extent to which it is actively promoted; Prevalence of bonfires; and Extent of fly-tipping

2.2.1 Effect of Free Garden Waste Collections on Quantities Collected When free garden waste collections are offered, there is strong evidence that more waste enters the collected waste stream than was hitherto the case. Figure 3 shows yields from a number of composting collections in various areas as presented in an earlier study5. The data is a little dated now, but gives some indication of what was typical in areas collecting biowaste in the recent past. Food waste was accepted by some of these schemes, but none, except the Isle of Wight (which was collecting only food waste), were measuring the separate contributions

5 David Mansell (2001) Study of Kerbside Collections Options for Organic Waste, First Phase Report; Avon Friends of the Earth. The highest yield in Castle Morpeth is achieved by a small scheme operating in an affluent area where gardens are very large.

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of food and garden waste to their collections. Some collections were accepting cardboard for composting but these were in the minority (three of the 21 schemes shown in Figure 3).

Figure 3: Kerbside Composting Collections Kg per Household in 2000/01

Figure 3 does not show clearly the frequency of collection, or whether the schemes are opt-in or opt-out. Nor does it show the nature of the container being used (bin or sack). Tentatively, however, one can surmise that the quantity of material being collected in schemes where garden waste is collected free of charge is almost always greater than 100kg per household per annum, more typically, around 200kg per household, and likely to be above that figure in some circumstances. It is interesting to note that these were figures obtained in 2000/01 when average per household waste arisings in England were 1.2 tonnes per annum, or 0.94 tonnes if only refuse collection plus recycled materials (including those from HWRCs) is included. These systems could have been accounting, therefore, for 20% or so of all waste being collected at the doorstep in these authorities.

From St. Edmundsbury, one study reviewed the quantity of material collected in 2002/3 on a month by month basis.6 This is shown in Figure 4. The quantity of collected material is of the order 334kg/hhld per year on average.

Figure 4: Month-by-month Collected Quantities for St Edmundsbury

6 Eunomia (2004) Current Practice in the Collection of Organic Wastes, Final Report to Devon County Council.

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A scheme covering around 6,000 households in North Lincolnshire was reviewed in the same study. Taking a 12 month moving average, per household captures (kg per household) of biowaste were analysed (see Figure 5). The quantity appears to vary a little, but always lies around the 225kg per household mark.

Figure 5: Twelve Month Moving Average Specific Capture of Biowaste from Kerbside (kg/household/year)

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In Forest of Dean, a free fortnightly garden waste scheme was operating alongside weekly refuse collection. The scheme is opt-in and around two-thirds of the households in the District, at the time of the investigation undertaken, had opted for the wheeled bin for garden waste (and some households asked for more than one bin).7 If the quantity collected is assessed based on all households in the District, 7 Eunomia (2004) Current Practice in the Collection of Organic Wastes, Final Report to Devon County Council.

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the average figure is around 162kg per household per year. If the number of bins issued is considered, the quantity collected is of the order 250kg per bin per year.

There is limited evidence of the degree to which home composting can act to constrain the collected quantity of material once free garden waste collections are in place. Fylde was (and still is) operating a free collection of garden waste, kitchen waste and cardboard. This operates in the context of one of the most comprehensive home composting promotion schemes in England (in Lancashire).

The average quantity of material collected per household per year can only be estimated from the data available to us since it is not clear exactly how many households have been included over the different months, and not all are on the alternating collection with refuse. If it is assumed that 75% were on the alternating system at the time of our interview, then the capture from these households over the year is likely to have been of the order of 180kg per household per annum. It is not possible to state with any certainty whether the strong promotion of home composting across Lancashire has had an impact on the quantity collected, although this does seem a marginally lower figure than is typically being observed in free collection systems, not least given the fact that the Fylde collection is not limited to garden waste only. This ignores the potential for influence by the nature of the housing stock.

Without more analysis of this nature, it is difficult to make clear statements about the impact of the home composting promotion other than that it would struggle to have the effect of constraining the overall quantity collected within pre-biowaste-collection levels (see below). It is possible, especially given the quantities shown, for example, for St Edmundsbury, that the specific captures are, on average, lower than they might otherwise be, but the evidence is too scant for this conclusion to be drawn.

Modelling work by Tucker and Speirs seems to confirm this perspective.8 Table 1 shows the modelled impact on capture rates of a free kerbside organics collection with different rates of compost bin promotion. The modelling shows the impact of (presumably) garden waste collections offered free of charge to householders. It is not made clear whether bin promotion as modelled here, involves an intensive approach to the promotion of home composting, including provision of advice. In addition, it seems that the capture of garden waste modelled is low relative to what typically can be expected in schemes offering free garden waste collection.

8 Peter Tucker and David Speirs (2002) Model Forecasts of Recycling Participation Rates and Material Capture Rates for Possible Future Recycling Scenarios, Report to the Cabinet Office Strategy Unit, July 2002.

11

Table 1: [Kerbside] Material Capture Rates with an Extension of Kerbside Green Waste Collections Region-wide plus a Modest Home Compost Bin Promotion (all recycling unless otherwise stated)

Fraction No bin

Promotion (%)

With modest bin promotion (%)

Change in Captures (%)

Kitchen compostable 2.7 2.3 -0.4% Kitchen non-compostable 2.4 3.1 +0.7% Garden 65.4 63.3 -2.2% (Total putrescible) (29.9) (29.0) -0.9% Source: Peter Tucker and David Speirs (2002) Model Forecasts of Recycling Participation Rates and Material Capture Rates for Possible Future Recycling Scenarios, Report to the Cabinet Office Strategy Unit, July 2002.

That having been said, it can be seen that the bin promotion barely influences the capture of material through the kerbside scheme. If promotion was effective, one would expect a noticeable change in the capture by the system. This is clearly not the case. The authors state:

Kerbside capture rates are only marginally depressed when home composting is increased.

They go on to comment:

This emphasises that increasing home composting does not obviate the need for centralized collections as well (though the tonnages available for those collections will of course drop).9

However, what if the quantity of garden waste in the collection system is influenced by the presence of the garden waste collection service as the evidence suggests? If this is the case, then many of the collection systems described above would, if they had measured their likely capture of material as a proportion of garden waste in the collected waste stream prior to the system change, be reporting capture rates well in excess of 100%, and in some cases, greater than 200%. In addition to new material being collected, is material which would otherwise have been taken to HWRCs.

It is suggested that the issue needs to be considered from a different perspective. If there is a free collection system for garden waste in place, it may make less difference whether an authority promotes home composting intensively or not. The more important issue is whether a kerbside collection of garden waste is necessary or desirable if there exists a potential to increase the quantity of material being collected at the kerbside, and if home composting is considered as desirable. As far as home composting promotion is concerned, it is suggested that it is increasingly difficult to achieve results where free garden waste collections are put in place. The convenience that free garden waste collections offer to households in terms of 9 Peter Tucker and David Speirs (2002) Model Forecasts of Recycling Participation Rates and Material Capture Rates for Possible Future Recycling Scenarios, Report to the Cabinet Office Strategy Unit, July 2002.

12

depositing garden waste tends to discourage dealing with the material at home through home composting.

European experience also supports the view that it is extremely difficult to constrain delivery of garden wastes through promotion of home composting where the garden waste collection is free at the point of delivery. Rather, the option of charging for garden waste collections (typically in much of Europe, with higher charges for collection of refuse being in place) needs to be available in order to further encourage home composting.10

Figure 6 illustrate the outcomes of a survey of home composting in Italian municipalities, showing the rates of home composting in those households with and without (shown with arrows) free garden waste collections. Participation rates are generally higher in municipalities without free garden waste collections.

Figure 6: Home Composting Rates in Italian Municipalities With and Without Free Garden Waste Collection (municipalities with garden waste collection)

10 These comments are based upon a number of study visits to European municipalities, as well as on reviews of performance of systems where charging of householders takes place. The minimisation effect of charging systems is often explained principally through reference to an increase in home composting / mulching. See, for example, Eunomia (2003) Waste Collection: To Charge or Not to Charge? Report for IWM(EB).

0.0%5.0%

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13

2.3 Charging for Garden Waste Collections Around75 local authorities in England charge for the collection of garden waste under existing powers11. Some authorities have asked householders to pay for sacks for garden waste collection. The intention is to restrict delivery of garden waste into the collection system, whilst continuing to provide a service to residents. Others provide a wheeled bin for the collection of garden waste and apply an annual charge for a fortnightly collection service.

However, little is known about the responsiveness of households to the price of garden waste collections. For reasons discussed below, this is somewhat disappointing. If an authority is to optimise a collection system in terms of both cost and quantity collected, it may be important to optimise the level of charging for garden waste to a) reduce garden waste in residual waste; b) constrain the quantity of additional garden waste collected by the collection system; and c) as far as possible, recover the costs of collection and treatment.

In authorities, where garden waste collections are charged for, and where the material is composted, collected quantities tend to be much lower than in cases where free collections are in place. So, for example, in Carrick, where the collection system covers 83% of the Districts 40,789 households, based on the data in Table 2, the specific capture per household covered is around 40kg per household per year.

This compares with quantities 5-8 times higher where the collection is not charged for (see above). This is significant, and is one reason why in some continental situations, charging is applied to biowaste collections to ensure there remains an incentive to continue, or to start, home composting. Of course, the other factor which constrains the collection of garden waste is that refuse collections are on a weekly basis (and no direct charging applies). In these circumstances, the policy of a council on side waste and garden waste collected in refuse assumes significance.

11 Under section 45(3) of the Environmental Protection Act 1990, local authorities may not charge for the collection of household waste, except in cases prescribed in regulations. Local authorities have the power, under paragraph 3 of Schedule 2 to the Controlled Waste Regulations 1992, to charge for the collection of garden waste.

14

Table 2: Evolution in Collection Quantities Before and After Introduction of Garden Waste Collection, Carrick (rounded to nearest tonne)

Domestic Refuse (tonnes)

Garden Waste

(tonnes)

Garden Waste per Household

(kg)

12 Month Moving Average Garden

Waste per Household (kg)

Jan-02 3404 Feb-02 2531 Mar-02 2740. Apr-02 3032 May-02 3195 Jun-02 2969 Jul-02 3383 Aug-02 3271 96 2.84 Sep-02 2936 161 4.75 Oct-02 2975 144 4.25 Nov-02 2692 77 2.27 Dec-02 2432 28 0.84 Jan-03 3332 33 0.98 Feb-03 2491 38 1.11 Mar-03 2673 86 2.55 Apr-03 2894 111 3.27 May-03 2913 156 4.61 Jun-03 2922 187 5.53 Jul-03 3300 183 5.40 38.40 Aug-03 3129 194 5.73 41.29 Sep-03 3047 197 5.81 42.35 Oct-03 2925 156 4.61 42.71 Nov-03 2534 101 2.98 43.42 Dec-03 2644 44 1.31 43.89

Like Carrick, Bath and North East Somerset charges for garden waste collections. Residents have the option of buying either paper sacks, or a wheeled bin. The charging system effectively implies that once a wheeled bin has been purchased, there is no incentive for households to reduce the set out of garden waste (on the contrary, they may seek to maximise the use of the service because they have paid for it).

It is clear that the charging system (as in Carrick) has had some effect in constraining the collected quantities, though it may be that those who are now bin subscribers are producing as much as those in many other areas (precisely because the marginal cost of collection is zero). The other factor (as with Carrick) which depresses captures is that refuse collection is weekly.

Our own review of authorities who charge for garden waste (and the quantities collected) also suggests the following:

15

There is a growing tendency for charged garden waste collections to include both annual charges for wheeled bins and sack-based charges, with residents given a choice;

Where only sacks are available, the suggestion is that the capture of garden waste per participating household is lower than where the option to rent a wheeled bin is available. This is consistent with the fact that once a property has acquired a wheeled bin, the marginal cost of additional quantities of material is zero as long as the bin volume is not exceeded;

Few, if any, authorities are able to give clear information concerning the number of bin users and the number who avail themselves of a charged for sack service;

It has not been possible, on the basis of evidence gathered thus far, to estimate a parameter indicating the price-responsiveness of households to charges for garden waste collections, either for bin-based (elements of) schemes or for sack-based (elements of) schemes. However, some studies have sought to do this overseas;

In schemes reviewed by Eunomia, the collected quantity per household to which the scheme is available is below what is typical in free services. The majority of figures lie between 30-90 kg/hhld, depending upon a range of factors.

There is, therefore, a strong indication of a price effect, but the magnitude of this, and its relation to the price level, is not clear.

2.3.1 Effects on HWRC Collections A key question in considering how much of the waste collected through free garden waste collections is actually additional waste, or simply waste diverted from one collection route to another, is the issue of how much waste collected at HWRCs falls as a consequence of the implementation of garden waste collections.

In earlier work, we suggested that when a free garden waste collection service is provided, bin waste arisings were likely to increase (on average) by about 180 kilogrammes per household per annum.12 We also suggested some of the increase would be due to garden waste previously deposited at HWRCs being collected at the kerbside instead (i.e., the material is simply moving from one management route to another), giving a net figure of 100kg per household per annum increase in waste arisings.

However, on the basis of further work,13 we now believe that the degree to which there is likely to be a major reduction in garden waste delivered to HWRCs is questionable. In his earlier work, Mansell noted:

12 Eunomia, Avon FoE and Network Recycling (2002) Maximising Recycling Rates, Tackling Residuals, Final Report to the CRN. 13 Eunomia (2004) Current Practice in the Collection of Organic Wastes, Final Report to Devon County Council.

16

Several of the schemes believed that garden waste collections [at HWRCs] had not been reduced as a result of the introduction of a kerbside collection service, but most of these were not well placed to judge as both collection services were often introduced or expanded at a similar time or the kerbside composting collections only covered a relatively small part of the district. 14

Later, working with Mansell, we noted that in Daventry, where there was a District-wide biowaste collection capturing large quantities of material, the garden waste yield at the two HWRCs in the District remained at 67 kg per household per year,15 which was about two thirds of that achieved by some of the high performing HWRCs in counties where no kerbside collections of garden waste were in operation.16 A rough estimate of the reduction in garden waste arisings at HWRCs when kerbside collections for garden waste are introduced was made based on the Daventry and high performing counties yields. Garden waste arisings at HWRCs from households without free garden waste collections were estimated to average 129 kg per household per year, implying, for Daventry, a drop of around 62kg per household (on average) at HWRCs when free garden waste collections were introduced. This can be compared with the collected quantity, which was in excess of 300kg per household. It would seem highly likely, on this basis, that there has been growth in the quantity of waste in excess of 100kg per household per annum.

This point that the increase in collected waste appears to be genuine is further illustrated by specific cases. For example, for Forest of Dean, Figure 7 shows all waste collected, including all kerbside collected waste and all waste collected at the nearest HWRC, and all waste collected minus the kerbside collected garden waste. This highlights the growth in total waste collected (see also Figure 8). The increase varies by month. Basic analysis suggests that the total waste excluding kerbside collected garden waste is, on average, around 150 tonnes less than in the absence of the scheme.

A 12 month moving average for the gap between the systems with and without garden waste collection suggests a difference of the order of 5,000 tonnes per year, which has been growing as the number of bins issued has increased (see Table 3).

14 David Mansell (2001) Study of Kerbside Collections Options for Organic Waste, First Phase Report; Avon Friends of the Earth.

15 At the time, there are two HWRCs in Daventry with different operators. The recycling rates (excluding rubble) achieved at each were 24% and 35%, suggesting there was still considerable room for performance improvement.

16 Eunomia, Avon FoE and Network Recycling (2002) Maximising Recycling Rates, Tackling Residuals, Final Report to the CRN.

17

Figure 7: Total Waste Collected, Including and Excluding Kerbside Collected Garden Waste (Forest of Dean)

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Figure 8: Kerbside Collection of Garden Waste and Total Collected Waste (Forest of Dean)

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18

Table 3: 12-month Moving Average for Kerbside Garden Waste Collections

Year ending (month) Jul-03 Aug-03 Sep-03 Oct-03 Nov-03 Dec-03 Jan-04 Moving Average Additional Tonnes Collected (over 12 month period, net of natural 2.5% growth)

2,832 3,408 3,820 4,160 4,674 4,775 4,859

Moving Average Annual Additional Capture Per Household (kg)

83 100 112 122 137 140 143

Moving Average Annual Additional Capture Per Bin Used (kg)1

129 155 173 189 212 217 221

1 Note that the number of bins used to calculate this is the number of bins at the end of the period

Figure 9 also supports the view that collecting garden waste does increase the quantity of material collected and does not simply shift the collected quantity from the HWRC to the separate collection system. In the first full year of the schemes operation in the Forest of Dean, the quantity of garden waste collected at the main HWRC appears to have increased relative to the previous year. A number of factors might explain this, including climate, and the operation of the site. Yet total waste quantities have changed little from the previous year (so it might be improved separation at the site rather than greater garden waste quantities which explain the better performance in respect of separately collected garden waste).

The quantity of garden waste collected at the kerbside in the summer months approximates to the total quantity of all waste collected at the HWRC in those months. This fact serves to re-emphasise the genuine nature of the increase in collected waste in Forest of Dean. The increase is not a consequence of a simple shifting from the HWRC into the kerbside collection. On the contrary, if anything, the deliveries to the HWRC may even have held up in the period under examination (though this is difficult to say given the influence of climate etc. from one year to another).

In Bath and North East Somerset, the quantity collected is smaller because the service is charged for (Figure 10). The collection shows an indiscernible impact on the quantity of domestic refuse collected. Figure 11 shows this in slightly more detail, and suggests that the kerbside collection of garden waste and cardboard is not leading to significant changes in the quantity of garden waste and cardboard collected separately at HWRCs. Of course, this statement could demand qualification if an improvement in segregation at HWRCs was masking a drop in deliveries.

19

Figure 9: Evolution in Garden Waste Quantities Collected from Kerbside, HWRC, and in all HWRC Waste (Forest of Dean) (tonnes)

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Figure 10: Evolution in Collected Quantities, Bath and North East Somerset (tonnes)

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20

Figure 11: Kerbside Organics Collections and Materials Collected at HWRCs, Bath & North East Somerset (tonnes)

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Figure 12 offers some support for this hypothesis. In other words, as the kerbside collection has increased, so has the quality of separation at HWRCs. Hence, whilst garden waste collected at HWRCs appears stable, it may be that a higher proportion of a smaller quantity is being separated at the site. This would imply that the garden waste collected at kerbside had some impact in terms of a reduction in the quantity delivered to HWRCs. Even this conclusion, however, has to be layered in caveats given the complexities of the situation and the seasonal variations possible.

2.3.2 System Considerations Notwithstanding all these points concerning the genuine nature of the increase in the overall quantity of material, other things being equal, garden waste collections do tend to lead to a reduction in total residual waste. Put in another way, if all the waste streams other than the garden waste which is separately collected from the kerbside are summed, this quantity tends to fall once garden waste collections are introduced. Intuitively, one would expect this fall to be related to the prevalence of garden waste in the kerbside collected waste prior to the introduction of the garden waste collection scheme. The relevant plot for the Forest of Dean is shown in Figure 13.

21

Figure 12: Quantities of Garden Waste and Cardboard Collected at HWRCs, and HWRC Disposals (tonnes)

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Figure 13: Residual Waste Quantities during Evolution of Garden Waste Collection (Forest of Dean)

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2.4 Findings from the WRAP Home Composting Research Much of the above has concentrated upon the effects of garden waste collection schemes at the scale of an authority. Work undertaken by WRAP has sought to model the effects of home composting from the household perspective.

This work suggests that the quantities of waste being composted by active participants is higher than was previously thought, especially in collection authority (WCA) areas with garden sizes averaging over 200m2. Here, an estimated 340kg of material per household per annum is dealt with through home composting. It is thought that 160kg of this might otherwise be collected as dustbin waste, whilst the remainder is material which would otherwise be taken to a HWRC (see Table 4). For WCA areas with smaller gardens (less than 200m2), the quantities are 180kg and 100kg per annum respectively. The national average suggests home composting households are reducing the input to the residual waste bin by around 115kg per annum.

The important point is that quite apart from any new arisings from a latent garden waste fraction (i.e. that which households might place into a biowaste container but which they do not currently collect for home composting), where people are discouraged from home composting, even if only passively, the potential for increased deliveries into the formal collection system clearly exists.

The WRAP research suggests that the distinction between home composted quantities rests upon the average garden size, which does not necessarily imply a split between rural and urban authorities. The distinction on the basis of average garden size is used later in this work to model the effects, at the household level, of different systems for collection and treatment of biowaste.

2.5 Summary The implications of the above analysis are not conclusive in the statistical sense. However, they appear to confirm the growing body of evidence that:

Free garden waste collections increase the quantity of waste arisings. In areas with high proportions of detached and semi-detached houses, quantities of garden waste collected can exceed 300kg per household. In normal weather and cropping conditions in the UK, lawn mowings from public and private areas are expected to be capable of yielding 2 to 4 kg per square metre per year of grass clippings. These quantities may be roughly doubled by trees and bush pruning and leaves from gardens. Such outcomes increase recycling rates, but they also increase the overall quantity of waste to be collected and treated.

The increase in collection of garden waste at the kerbside is not offset on anything like a one-to-one basis by a reduction in the collection at HWRCs, or by a reduction in quantities of refuse collected. Hence, a genuine increase in collected waste can be expected (as opposed to an increase in collected garden waste simply reducing quantities collected through other routes). In some systems, the ratio of new material to material previously collected might be as high as 2:1 for garden waste.

23

Table 4: Effects of Home Composting in Terms of Reduction in Biowaste Delivered through Different Collection Routes (kg/hhld/yr)

Reduction in: Results based on questionnaires & waste analysis Results based on district models

(based on DEFRA local authority statistics 2003/04)

Overall model Average garden size greater than 200m2 Average garden size less

than 200m2 Dustbin waste (total) 84

115 160 100

WRAP bins v Non-participants

42 Kitchen waste in dustbin Non WRAP bins

v Non-participants

24

Dustbin waste + CA waste

220 340 180

Source; WRAP

24

Charging for garden waste has the potential to considerably reduce the quantity of garden waste collected. We do not know, however, how this affects the quantity of garden waste in residual waste (as compared with free garden waste collection systems).

The reasons for this increase in collected waste appear to be:

Some people stopping composting, or compost less, at home; People are inclined to keep gardens more tidy (clippings not left on lawn, leaf

fall / fallen fruits cleared up - people may purchase garden power tools to enhance ease of pruning, clipping, and cutting);

Fewer bonfires; New housing stock: large estates with garden plots, and more gardens; and Waste previously fly-tipped re-enters the formal collection scheme.

Understanding of these influences is improving but currently, evidence is more than anecdotal, but not good enough to provide clear statistical evidence of estimates of dynamic change.

There are ways of limiting the increase in collected quantities. These include:

Restricting available volume (either through bin / sack size, or reducing collection frequency);

Charging for each set-out of garden waste (i.e. ensuring that the marginal cost is not zero, as it is in cases where households rent a bin); and

Specifying a containment method, such as sacks, and limiting the number that can be set-out for collection.

Active promotion of home composting prior to introducing any collection backed with clear communications on when to use kerbside services

These can reduce the effect, and high charges may indeed nullify it, but such approaches raise questions about the rationale for the collection, and certainly, the wisdom of seeking to capture garden waste in order to enhance recycling rates. As will become clear, there may be reasons why less frequent, or charged for schemes, may have a role to play in integrated systems which keep separate the collection of garden waste, and that of kitchen waste.

25

3.0 THE POLICY CONTEXT The policy context for this study is a fluid one. There are issues being debated, and possibilities on the horizon, in both UK policy (and the policies and approaches of the different devolved administrations have already shown a tendency to diverge) and in European policy. What follows in this section is a description of the legislative and policy context of greatest relevance for this study, including a commentary on some of the ongoing discussions. EU legislation is not mentioned where implementing legislation for the UK already exists. We have set out to identify and explore some of the incentives implied by the existing system to the extent that they may affect the key focus of this research, and the collection and treatment of biowastes.

For the purpose of this study, biowastes are considered as being distinct from biodegradable wastes. The distinction is made as follows:

Biodegradable wastes all wastes deemed biodegradable for the purposes of the Landfill Directive, including paper and card, textiles, food waste, garden waste, wood;

Biowastes food (or kitchen) and garden wastes, including those wastes of a putrescible nature which are not obviously either, such as pet faeces etc., and including those garden wastes which are less fermentable, such as woody garden materials.

For the sake of further clarification, the analysis is focused on biowastes collected from households.

3.1 The UK ABPR and Recycling Targets 3.1.1 Regulating Animal By-products Shortly after local authorities were given statutory recycling targets for recycling and composting, the amendment to the Animal By-products Order (ABPO) made it illegal to compost in open windrows kitchen waste.17 The Environment Agency Policy Guidance Note concerning Composting and Landspreading and the Implications of the Animal By-products Order 2001 pointed out:

The Animal By-Products (Amendment) (England) Order 2001 (SI No. 1704) and the Animal By-Products (Amendment) (Wales) Order 2001 (SI No. 1735) amend the Animal By-Products Order 1999 (SI 646) (ABPO). The effect of this is to make it an offence to, inter alia, allow livestock to have access to some catering wastes or compost produced from them. [] The ban applies to catering waste which contains animal carcasses, parts of animal carcasses or products of animal origin (or has been in contact with these) or which originates from premises where they are handled or where foodstuffs containing or coming into contact with them are prepared or

17 Environment Agency Policy Guidance Note concerning Composting and Landspreading and the Implications of the Animal By-products Order 2001.

26

produced. This therefore includes any food or kitchen waste from most households. []

The implications are that catering waste of a type described above, including source segregated kitchen waste as collected by local authorities, cannot be composted or spread on land where birds can get to it. Additionally, compost produced from such catering waste cannot be spread on any land to which birds can get access.

In the context of concerns regarding the potential risk posed to animal health from composting processes, Defra commissioned a risk assessment which sought to quantify the risk associated with composting processes. The assessment and its recommendations were, by and large, accepted by Defra as the basis for establishing policy regarding the processes to be used for the composting of material containing food waste from households.

When it became clear that the UKs mechanism for implementing the EU Animal By-products Regulation (the UK Animal By-products Regulations, or UK ABPR) would allow composting of food waste, but only in enclosed systems which had been approved by the State Veterinary Service (SVS) (in addition to planning and licensing approvals) some local authorities that had maintained the co-collection of garden and uncooked kitchen waste (vegetable peelings, etc) through the preceding years of legislative uncertainty effectively ceased the collection of kitchen waste alongside garden waste. This was because they did not have an appropriate (i.e. enclosed) facility to deal with kitchen wastes.

Since the UK ABPR has clarified, at least to some degree, the legal position, there has been increased interest in kitchen waste collections. However, to date much of this interest has been in collecting kitchen waste in the same receptacle as garden waste, as opposed to the separate collection of kitchen waste only. In the UK, authorities such as Preston, Ealing, Richmond and some of the districts in Somerset are operating kitchen waste only collections, and others are planning its introduction.

3.1.2 The Effect of Recycling Targets (based on % by weight) Following the announcement in Waste Strategy 2000, to the effect that local authorities in England would be set statutory recycling targets, the Government established specific recycling targets for 2003/4 and 2005/6. These were designed to help England as a whole to meet recycling targets of 18% of household waste, and 25% of household waste by 2003/4 and 2005/6, respectively.

For some WCAs, with high targets to achieve, this required the collection of biowastes. Following on from the ABPO, many were left with little option other than to start collecting garden waste only as the collection of dry recyclables alone would not have secured their target.

There are several reasons why these targets have, in some cases, led to sub optimal outcomes. The main reason is that the collection of garden waste appears (for reasons described above) to lead to the collection of material which was not previously collected as waste. This imposes an additional cost on the overall system with, arguably, no gain other than in the reported BVPI figures.

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Percentage recycling rates tend to focus attention on collecting those materials which generate the greatest quantity of material. Even though (no charge) garden waste collections tend to lead to an increase in collected waste, they also increase recycling rates, especially for WCAs. As well as increasing the overall quantity of garden waste collected, some of the garden waste is diverted from HWRCs and into the kerbside collection system. Many of the top performing WCAs collect garden waste kerbside, with some achieving BVPIs of 25% or more for composting (BVPI 82b).

The recent consultation on the new Waste Strategy for England raised questions concerning the appropriateness of the existing targets, and the potential for providing incentives for reducing waste. In the devolved administrations, there is considerable interest in developing strategies to prevent waste, whilst the Commissions proposals for a new Waste Framework Directive would also seem to be pointing towards a requirement for Member States to develop a waste prevention programme. It remains to be seen what targets might be set for local authorities in England in the future.

3.2 Waste and Emissions Trading Act The Waste and Emissions Trading Act 2003 essentially transposes the Landfill Directive into UK law, and was granted Royal Assent on 13 November 2003. The legislation gives the Secretary of State, as the relevant authority, powers to impose a duty upon waste disposal authorities to ensure that they landfill no more biodegradable municipal waste than that for which they possess allowances. This legislation was on the horizon for several years, and the possibility of using a system of (tradable) allowances as the mechanism for implementing the Landfill Directive had been discussed since the late 1990s.

3.2.1 Landfill Allowances & Trading Scheme (England) Regulations 2004 In England, the rules surrounding the allocation of allowances, and the mechanisms and modalities for their trading were established in the Landfill Allowances & Trading Scheme (England) Regulations 2004 (LATS Regulations).

Of particular significance to this study is the way in which the biodegradable content of landfilled waste will be calculated. The Regulations state (Part 3, Reg.13):

(2) For the purposes mentioned in paragraph (1) it must be assumed that -

(a) the amount of biodegradable municipal waste in an amount of collected municipal waste is 68% by weight (rounded up to the nearest tonne);18

This assumption simplifies the calculation of the biodegradable content of landfilled waste, especially where no adequate compositional data exist (which is probably still the majority of places).

However, it is recognized that it is unlikely that all local authorities will have similar waste composition. It is well known that (amongst other things) differences in

18 Landfill Allowances & Trading Scheme (England) Regulations 2004, http://www.opsi.gov.uk/si/si2004/20043212.htm. The figure of 68% would be, in Scotland, Wales and Northern Ireland, 63%, 61% and 71%, respectively.

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housing types and differences in socioeconomic standing will influence the composition of household waste. Another factor which will influence composition is the nature and quantity of commercial waste collected as municipal waste in any WDA area. Whether this is collected at HWRCs or at commercial premises on collection rounds is likely to determine how much of the non-household waste is, for example inert rubble or biodegradable paper.

Importantly the decision to set the composition of collected household waste at 68% has the following consequences:

if a particularly successful initiative involving home composting is in place, then it may well be that less biodegradable waste is being collected. However, the assumption that the composition of collected municipal waste is always constant would imply that the authority concerned would only be credited with a reduction in the quantity of biodegradable material collected of 0.68 tonnes for every tonne of BMW composted at home; and

if, on the other hand, a local authority sets out to collect garden waste from the doorstep at no charge, the quantity of waste collected may be expected to increase (see Section 2.2 above). If the 68% composition assumption is adhered to, then on a mass balance basis, even though 100% of the increased quantity of waste will be biodegradable, the current approach assumes that only 68% of the additional tonnage is BMW. Table 5 shows the effect of this. The more additional waste that is collected for composting, then the less the calculated quantity of BMW in residual waste becomes. This is despite the fact that in the calculation (for the sake of making the point) it has been assumed that nothing has happened to the nature of waste being landfilled. All that has happened is that additional biowaste has been collected.

Table 5: Hypothetical Effects of Increased Garden Waste Collections on LATS Balance

Before Garden Waste Collection (tonnes per

household)

Additional Garden Waste Collected (tonnes / hhld)

Total Waste (tonnes/hhld)

BMW in Waste (68%)

Calculated BMW in Residual Using Mass

Balance Method 1.00 0.10 1.10 0.75 0.65 1.00 0.20 1.20 0.82 0.62 1.00 0.30 1.30 0.88 0.58 1.00 0.40 1.40 0.95 0.55 1.00 0.50 1.50 1.02 0.52 1.00 0.60 1.60 1.09 0.49 1.00 0.70 1.70 1.16 0.46 1.00 0.80 1.80 1.22 0.42 1.00 0.90 1.90 1.29 0.39 1.00 1.00 2.00 1.36 0.36 1.00 1.10 2.10 1.43 0.33

The current method effectively rewards local authorities for collecting and treating additional waste as long as it is biodegradable.

The reverse applies to measures which reduce the amount of waste to be managed. If, in cutting the lawn, a householder chooses to grass mulch, or to home compost,

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the effect is as shown in Table 6. Because the home composted material is deemed, under the mass balance approach, to be only 68% biodegradable, the contribution made by home composting to reducing the biodegradable content of collected waste is not fully recognised.

Table 6: Effect of Home Composting on Assessment of Biodegradable Content of Waste Using Mass Balance Method

Before Home Composting Promotion

(tonnes / hhld)

Effect of Home Composting Promotion

(tonnes / hhld)

Waste Collected (tonnes/hhld)

BMW in Waste Collected (68%, mass balance

approach)

Actual BMW in Waste

Collected

1.00 0.01 0.99 0.67 0.67 1.00 0.02 0.98 0.67 0.66 1.00 0.03 0.97 0.66 0.65 1.00 0.04 0.96 0.65 0.64 1.00 0.05 0.95 0.65 0.63 1.00 0.06 0.94 0.64 0.63 1.00 0.07 0.93 0.63 0.61 1.00 0.08 0.92 0.63 0.60 1.00 0.09 0.91 0.62 0.59 1.00 0.10 0.9 0.61 0.58

Indeed, if the material which is home composted is material which would otherwise have been separately collected for composting, then home composting actually worsens the position of the local authority under LATS. This is because:

1. Composting 1 tonne of separately collected biowaste effectively translates into a one tonne credit in terms of landfill allowances;

2. Home composting of 1 tonne of biowaste effectively translates into only 0.68 tonnes of credit in terms of landfill allowances;

3. Consequently, if the material which is home composted is material which would otherwise have been set out for separate collection, the net effect to the authority, in terms of landfill allowances, is to lose a credit of

a. (1-0.68) = 0.32 allowance equivalents. This situation is now under review. Defra has made it clear that it remains keen to support home composting and now that WRAP has completed the home composting diversion model, WRAP and Defra are jointly running a consultation exercise on the role of home composting in the context of the Landfill Directive BMW diversion requirements. This consultation is on-going and covers the whole of the UK involving the devolved administrations, the local government associations and other relevant local authority bodies.

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3.3 Biowaste Directive / Thematic Strategy for Soil Protection The 2nd Draft of the Biowaste Directive emerged in 2001.19 It contained three elements which would have been of major significance had the Directive come into force in the form of that Draft. These related to:

Requirements for source separation;

Standards for processes and outputs (distinguishing between products and wastes); and

Related to the issue of standards, the eligible use of outputs on land.

In April 2003, the European Commission adopted a Communication on a Thematic Strategy for Soil Protection. 20 This stated:

By the end of 2004 a directive on compost and other biowaste will be prepared with the aim to control potential contamination and to encourage the use of certified compost.

A decision was made in November 2003 to merge discussions for the revision of the Directive on sewage sludge recycling to agricultural land and the initiative on the biological treatment of biodegradable waste under the Thematic Strategy for Soil Protection. In the same month, the European Parliament passed a resolution on the Commissions Communication. Paragraph 18 of that resolution:

18. Urges the Commission to revise Directive 1986/278/EEC(7) on the use of sewage sludge and draw up a directive on compost; stresses the need to intensify research in this field so as to boost its potential for the recovery of soil lacking in organic matter and bring together waste management and soil protection and enrichment;

In December 2003, the European Commission issued a Draft Discussion Document in which the issues raised by the proposed Biowaste Directive, and expected revisions to the Sludge Directive, were discussed.

There have since been discussions that the Biowaste Directive has been dropped by the Commission. The Commission does indeed appear to have adopted this approach. The Thematic Strategy on Prevention and Recycling states:21

There is no single environmentally best option for the management of biowaste that is diverted from landfills. The environmental balance of the various options available for management of this waste depends on a

19 European Commission, DG Environment (2001) Working Document: Biological Treatment of Biowaste, 2nd Draft, Brussels, 12 February, 2001. 20 The European Commissions Communication to the Council and the Parliament Towards a Thematic Strategy for Soil Protection was the starting point for the discussions around a Strategy for Soil Protection.

21 European Commission (2005) Taking Sustainable Use of Resources Forward: A Thematic Strategy On The Prevention and Recycling of Waste, Communication From The Commission To The Council, The European Parliament, The European Economic And Social Committee And The Committee Of The Regions, Brussels, 21.12.2005.

http://www3.europarl.eu.int/omk/omnsapir.so/pv2?PRG=CALDOC&FILE=20031119&LANGUE=EN&TPV=PROV&LASTCHAP=12&SDOCTA=11&TXTLST=1&Type_Doc=FIRST&POS=1#EXPL_050707_7_7#EXPL_050707_7_7

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number of local factors, inter alia collection systems, waste co

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