Department for Environment, Food and Rural Affairs (Defra) on Waste

Waste Hierarchy Guidance Review 2012

"The evidence exercise for the review of the Waste Hierarchy Guidance ... [closed] on 30 June 2012.

"The expert panel comprising both independent specialists and scientists from Defra, DECC, WRAP, the Environment Agency and the Welsh Government [is considering] the material submitted. We are expecting to publish the revised Waste Hierarchy Guidance at the end of the year or early in the New Year.

"The current guidance is based primarily on life-cycle assessment, the review will use the same criteria, but will also consider evidence based on other forms of life-cycle thinking including ecological foot-printing.  We are aware that consideration of such slightly different criteria has led to a different hierarchy of options for some materials in the Welsh Government’s guidance.

"We are therefore particularly interested in evidence for those areas where the English and Welsh guidance currently differs, including:

• high and low efficiency energy recovery
• open loop recycling, e.g. of glass and plastics
• plastics energy recovery vs landfill; and
• paper energy recovery vs composting

"We are also seeking views on the need for guidance on non-hazardous materials or products other than those already included, [and] evidence to support any suggested deviations from the standard hierarchy for such types if waste.

"In considering the evidence submitted, a higher weighting will be given to evidence which is peer-reviewed; recent and represents UK conditions."

Link to DEFRA
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Introduction to the Waste Hierarchy

Many businesses are unaware of how significantly waste impacts on their bottom line. As the demand for materials grows worldwide, raising input costs, it makes sense for businesses to adopt the waste hierarchy.

Article 4 of the revised EU Waste Framework Directive (Directive 2008/98/EC) sets out five steps for dealing with waste, ranked according to environmental impact – the ‘waste hierarchy’.

Prevention, which offers the best outcomes for the environment, is at the top of the priority order, followed by preparing for re-use, recycling, other recovery and disposal, in descending order of environmental preference.

Stages	Include
Prevention:	Using less material in design and manufacture. Keeping products for longer; re-use. Using less hazardous materials
Preparing for re-use:	Checking, cleaning, repairing, refurbishing, whole items or spare parts
Recycling:	Turning waste into a new substance or product. Includes composting if it meets quality protocols
Other recovery:	Includes anaerobic digestion, incineration with energy recovery, gasification and pyrolysis which produce energy (fuels, heat and power) and materials from waste; some backfilling
Disposal:	Landfill and incineration without energy recovery

The waste hierarchy has been transposed into UK law through the Waste (England and Wales) Regulations 2011. The Regulations came into force on 29 March 2011. The provisions relating to the hierarchy (set out at in Regulations 12, 15 and 35) came into force on 28 September 2011.

Defining the waste hierarchy stages

The definitions of each of the stages can be found in Article 3 of Directive 2008/98/EC). Non-exhaustive lists of disposal and recovery operations can be found in Annexes I and II of the Directive.
‘prevention’ means measures taken before a substance, material or product has become waste, that reduce:
(a) the quantity of waste, including through the re-use of products or the extension of the life span of products;
(b) the adverse impacts of the generated waste on the environment and human health; or
(c) the content of harmful substances in materials and products;
‘re-use’ means any operation by which products or components that are not waste are used again for the same purpose for which they were conceived;
‘preparing for re-use’ means checking, cleaning or repairing recovery operations, by which products or components of products that have become waste are prepared so that they can be re-used without any other pre-processing;
‘recycling’ means any recovery operation by which waste materials are reprocessed into products, materials or substances whether for the original or other purposes. It includes the reprocessing of organic material but does not include energy recovery and the reprocessing into materials.
‘recovery’ means any operation the principal result of which is waste serving a useful purpose by replacing other materials which would otherwise have been used to fulfil a particular function, or waste being prepared to fulfil that function, in the plant or in the wider economy.
‘disposal’ means any operation which is not recovery even where the operation has as a secondary consequence the reclamation of substances or energy.

Deciding the priority order for each waste material

Our guidance is based on the best evidence currently available. As waste management technologies evolve, so their impact on the environment relative to other options may change.

The current research shows that for food, anaerobic digestion is environmentally better than composting and other recovery options. The evidence also indicates that for garden waste and for mixtures of food waste and garden waste, dry anaerobic digestion followed by composting is environmentally better than composting alone.

Likewise, the scientific data for certain waste management technologies is currently limited, eg for pyrolysis and rendering. So we are unable to determine their environmental benefits relative to other options within the hierarchy.

Businesses and local authorities may consider other factors when they make decisions on waste, including social and economic impacts, and technical feasibility. These factors are will vary in line with the size of an organisation, the range of materials it handles and its location. The relevance of these factors will have to be weighed on a case-by-case basis.

As new technologies emerge, we will review the evidence available annually and update our guidance on the hierarchy accordingly.

Anaerobic digestion – environmentally preferable to composting

The scientific evidence we currently have, based on life-cycle analysis, shows that for food, anaerobic digestion (AD) is environmentally better than composting and other recovery options. The evidence also indicates that for garden waste and for mixtures of food waste and garden waste, dry anaerobic digestion followed by composting is environmentally better than composting alone.

This is because anaerobic digestion produces both biogas, which can be used to generate vehicle fuel, heat, electricity, combined heat and power, and digestate, which can be used instead of fossil fuel-intensive fertilisers. The combination of both outputs means that anaerobic digestion is environmentally preferable to composting.

The Directive does not mandate the use of one option over the others. Businesses and local authorities may consider other factors when they make decisions on waste, including social and economic impacts, and technical feasibility.

The evidence indicates that for garden waste and for mixtures of food waste and garden waste, which are not suitable for dry anaerobic digestion composting is environmentally better. The relative merits of composting depend on the compost being used in place of fertiliser or peat. In terms of greenhouse gas emissions composting and energy recovery are broadly similar.

Recycling and energy from waste

Recovery activities such as Energy from Waste are also a key part of the hierarchy. The evidence shows that for most materials recycling is better for the environment than energy for waste (EfW) and that EfW is better than landfill.

The Government wants to reduce residual waste. However, there will be a need to deal with this type of waste for the foreseeable future and recycling alone cannot currently meet the ambition for diversion from landfill. There is no immediate risk of EfW facilities being deprived of feedstock.

Other sources of support

The Environment Agency has produced advice on the Waste (England and Wales) Regulations 2011.

Separate guidance for England and Wales

In England, the decision has been made to use a range of criteria to inform the waste hierarchy – climate change; air pollution; water pollution; and resource depletion. In Wales, the hierarchy is informed by ecological footprinting. Because of this difference in methodology, the two guidance documents are not always the same, although they often reach similar conclusions. Separate guidance will be produced in Wales in due course.