1. When appropriate measures apply
Assessing the appropriate measures that will apply to a permitted facility that handles biowaste.
This guidance applies to aerobic and anaerobic processes including:
- composting in open-air and closed (in vessel) systems
- aerobic processing of organic fractions by mechanical and biological treatment (MBT) and mechanical heat treatment (MHT)
- thermophilic aerobic digestion (TAD)
- anaerobic digestion (AD) including the combustion or upgrading of the resulting biogas and treating the digestate (anaerobic treatment can include wet, dry and dry-batch digestion)
- aerated lagoons and activated sludge (as a waste water treatment)
- collecting and storing methane from lagoons and tanks and upgrading to biomethane
- treating sewage sludge using any of these biological processes
- storing feedstock, compost and digestate
- receiving wastes destined for biological treatment
There is overlap between best available techniques (BAT) for waste installations and necessary measures for waste operations. The Environment Agency uses the term ‘appropriate measures’ to cover both sets of requirements.
This guidance sets out what you must consider when you assess the appropriate measures for your facility. It is not definitive and it does not replace your obligation to assess appropriate measures fully for your site.
Some measures may not be suitable for or relevant to your operation. Appropriate measures will depend on the:
- complexity of the activities being carried out
- size and nature of the activities
- location of the site
Where an operator wants to propose an alternative measure, this must achieve the same level of environmental protection. The operator must also provide evidence of why the alternative is equivalent to (or better than) what this guidance proposes.
In certain situations, a higher standard of environmental protection may be needed, for example:
- where there are local sensitive receptors
- if the facility is affecting the local environment or human health despite using appropriate measures
- if there is a risk that you may breach an Environmental Quality Standard
Other technical guidance relating to emissions, odour and noise may also apply.
Where the biological treatment is directly connected or associated with another regulated activity or process, specific technical guidance may apply.
Operations that are permitted to accept, store, handle, treat or transfer the following wastes must also comply with the requirements in Chemical waste: appropriate measures for permitted facilities:
- hazardous waste
- mirror entry waste
- laboratory smalls
- chemicals
Combustion plant with a rated thermal input equal to or greater than 1 megawatt (but less than 50 megawatts) must have a permit and comply with the relevant requirements of the Medium Combustion Plant Directive (Directive (EU) 2015/2193). Specified generators which are used to generate electricity must also have a permit and comply with the relevant requirements of the specified generator regulations. Additional guidance is available from the Environment Agency.
This guidance applies to the following activities for the waste water treatment sector, the:
- biological treatment of waste water not covered by the Urban Waste Water Treatment Directive (UWWTD)
- biological treatment of sludges, centrate liquors and other wastes generated by the waste water treatment process
- importation of wastes or effluents (excluding sewage, sewage sludge and septic tank sludge) to the works where they are fed into the UWWTD biological treatment process
Where measures apply to all processes and operations this is stated. Where measures are process-specific this is stated.
The appropriate measures in this guidance apply to both new and existing facilities that treat biodegradable and organic waste.
New facilities
All new facilities must implement the relevant appropriate measures, or a fully justified equivalent. These must be in place before waste treatment operations start.
New installations (including new or replacement plant at existing facilities) must comply with any relevant best available technique (BAT) associated emission level (AEL) as set out in the published Waste Treatment BAT Conclusions document. They must do this from the start of their operations, unless we approve a derogation.
Existing facilities
Installations permitted after 17 August 2018 must already be BAT compliant.
Existing installations permitted before 17 August 2018 must comply with the BREF and BAT AELs by 17 August 2022.
Where operators are unlikely to comply with a BAT AEL by 2022 they must apply for a derogation. If you cannot comply, you must contact the Environment Agency as soon as possible.
Existing waste operations should already be applying appropriate measures depending on their risk.
Where we have identified that an operator needs to (and can) improve the facility, or there is significant environmental risk or actual pollution, we will require the operator to apply appropriate measures.
We have reviewed and revised our standard rules to reflect these measures and will review all bespoke permits to make sure all necessary appropriate measures are applied. We will vary bespoke permits to meet the required standards.
Operators can deliver some improvements by reviewing and amending their management system and progressing a voluntary scheme of improvement.
Improvements at existing facilities are likely to fall into 1 of the following 2 categories.
1. Standard ‘good practice’ requirements
Where improvements are relatively low cost, operators should prioritise them based on the risk posed by their facility. They should implement these improvements as soon as possible and no later than 12 months after the publication date of this guidance. For example, these improvements could be:
- updated management systems
- waste pre-acceptance, acceptance, handling techniques and waste transfers off site
- equipment and infrastructure maintenance
- measures to prevent fugitive or accidental emissions
- appropriate monitoring equipment
- waste, water and energy efficiency measures
2. Longer term and capital-intensive improvements
Where local environmental impacts are affecting sensitive receptors an operator may have to take action immediately. The Environment Agency may require operators to complete improvements within the timeframe it sets. These may include capital-intensive improvements.
There is an existing requirement for operators to comply with their permits. Operators should periodically review, modify and update management, process systems or equipment in line with existing permit conditions. This may include periodic capital investment.
Examples of capital-intensive improvements include:
- reviewing, revising and installing abatement equipment
- significantly redesigning the layout of the facility, including, for example, the design and installation of new buildings or treatment plant to prevent ongoing pollution or reduce the risk of pollution
- replacing tanks or other primary infrastructure
- installing secondary containment where there is a significant risk
Capital-intensive projects may need permission from other regulators and the Environment Agency will take this into account when considering improvement timescales. It expects operators to send their permission requests to other regulators in a timely manner. In some cases, the Environment Agency will be a consultee (for example as part of the planning process).
BAT conclusions are the reference for setting permit conditions for installations. The Environment Agency sets emission limit values as the competent authority for England. We set these values to make sure that, under normal operating conditions, emissions do not exceed the levels associated with the best available techniques as set out in the Waste Treatment BAT Conclusions. Emission limit values may be stricter based on:
- the location of sensitive receptors (such as residential properties)
- the stated design of plant with point source emissions
The Waste Treatment BAT Conclusions inform the appropriate measures for waste operations. Although it’s not mandatory to set emission limits, the Environment Agency may set them as appropriate to make sure:
- the design and effectiveness of abatement plant is maintained
- people and the environment are protected