Stop, Sort, Burn, Bury - incineration in the waste hierarchy: independent review

Executive Summary

The Independent Review of the Role of Incineration in the Waste Hierarchy ('the Review') commenced in November 2021, with this report being delivered in April 2022. The Review, chaired by Dr Colin Church, set out to answer five key questions:

1. Given Scotland's waste management ambitions and current progress towards these, what capacity is required to manage residual waste in Scotland?

2. What are the options for managing residual waste?

3. What are the economic, environmental and social trade-offs of those residual waste management options?

4. How do we decide where capacity should be located, and in what form?

5. What can be done to improve existing residual waste treatment facilities in terms of carbon performance and societal impacts?

The Review was asked by the Minister to prioritise the assessment of national capacity requirements (Topic 1). To respond to these topics, the review considered existing evidence and commissioned additional capacity modelling, an appraisal of waste treatment options and a rapid evidence review of the potential health impacts of incinerating waste. Additionally, the Review opened a Call for Evidence, allowing stakeholders to submit written and verbal evidence and considerations for the Review.

During its review of available evidence, it became apparent to the Review that the accessibility, quality and quantity of some data around waste management in Scotland is lacking in some key aspects. To address this, the Review recommends improvements to the Scottish Government's waste management data and for the Scottish Government, industry and local authorities to improve the transparency of their data (see Recommendation 2 and Recommendation 3).

Capacity to manage residual waste in Scotland

Overall, the capacity analysis completed for the Review suggests that there is likely to be a capacity gap in 2025, when the biodegradable municipal waste (BMW) ban comes into force. This will clearly be exacerbated if the ban is extended to include all non-municipal biodegradable waste. While this capacity gap could be closed by Scotland achieving its waste and recycling targets, stakeholders raised concerns about the likelihood of achieving these targets, drawing on experience and comparisons with other nations as evidence of what could be possible. The Review recommends that Scotland should limit the granting of further planning permissions for incineration infrastructure (see Recommendation 4). Further to this, the Review recommends that an indicative cap for the residual waste treatment needed in Scotland should be developed, and that this should decline over time as Scotland transitions towards a fully circular economy (see Recommendation 5).

The short term nature of the capacity gap, balanced against the long term likelihood of overcapacity, highlighted the difficulty in using infrastructure with long operational lifespans alone to treat residual waste. The Review finds that the risk of lock-in in waste management contracts is genuine, and recommends that local authorities specifically address this within their contracts (see Recommendation 6).

Residual Waste Management Options

The best form of residual waste treatment is preventing it occurring in the first place, through reducing waste and recycling. The Review recommends that the Scottish Government does more to reduce the proportion of recyclable materials in the residual waste stream (see Recommendation 1).

In terms of managing the remaining residual waste, the Review assessed the feasibility of a number of residual waste treatment options. In consideration of this assessment, along with a further appraisal of social, health and climate considerations relating to waste treatment, the Review finds that incineration's current place within the waste hierarchy, where overall it is preferable to other forms of residual waste treatment, but less desirable than reducing and recycling waste, is correct. It recommends that the most feasible waste treatment options are incineration, landfill and export of waste (see Recommendation 7).

Trade-Offs

The Review considered the health and social impacts of residual waste management in Scotland. This included a Rapid Evidence Review on health impacts from Public Health Scotland, which confirmed its previous view that such impacts were likely to be small. The Review also considered the impacts: on local amenity; the link between deprivation and location of facilities; perception and employment, as well as the Scottish Landfill Communities Fund and heat and energy offtake. The Review additionally heard from stakeholders regarding the difficulties they experienced engaging with planning processes and difficult relationships with local facilities. The Review finds that communities deserve more authentic and committed engagement from local authorities and industry than is currently sometimes the case (see Recommendation 8 and Recommendation 9).

Decarbonisation

The Review has found that currently, incineration is less damaging to the environment than landfill. However, increased incineration, changes to waste composition and wider decarbonisation will make this less favourable over time. To assist in monitoring this, the Review has recommended that greenhouse gas (GHG) emissions from incineration are reported separately from other energy-related emissions. (see Recommendation 12)

Separate work has been commissioned to inform further consideration of opportunities to decarbonise the residual waste treatment infrastructure sector in Scotland, with the main focus on waste incineration (Topic 5). In the meantime, the Review has provisionally recommended improving pre-treatment processes before incineration, with a particular focus on plastics (see Recommendation 13). Additionally the Review has provisionally recommended that combined heat and power should be pursued for as many incineration facilities as possible (see Recommendation 14).