Consultation outcome

Standard rules permit consultation No 27: summary of consultation responses

Published 17 August 2023

1. Introduction

The Environmental Permitting (England and Wales) Regulations 2016 allow us to make standard rules to reduce the administrative burden on business while maintaining environmental standards.

The purpose of this consultation was to engage with stakeholders to obtain their views on the proposal for a new standard rules permit for the capture, treatment and storage of biogas from lagoons and tanks.

2. How we ran the consultation

We formally consulted from 17 August 2023 until 9 November 2023, using our Citizen Space consultation website.

We asked 10 questions. Questions relating to the draft standard rules permit were set out in questions 1 to 5 of the consultation. A question relating to the generic risk assessment was set out in question 6. Questions relating to the business impact were set out in questions 7 to 10.

We received 7 responses to the consultation. However, not all respondents provided answers to all the questions.

Of the 7 responses we received:

• 3 were from an individual
• 4 were on behalf of an organisation or group

One respondent did not submit any comments therefore only 6 responses where considered.

A list of the names of the organisations that responded to the consultation is provided in the annex at the end of this document.

3. Summary of the main findings and actions we will take

The consultation responses identified some concerns with the new permit, particularly with the activity limits. But were overall supportive of the operating techniques and generic risk assessment.

We are now reviewing the draft permit with reference to the comments received and we will produce the final version for publication on GOV.UK. We hope to publish this permit in summer 2024.

4. Responses to the proposed new permit: questions 1 to 5

Question 1. Limits on permitted activities.

The draft rules limit the activities to:

• collect and store biogas from engineered lagoon storage or tank or from an existing lagoon which meets the criteria specified in these rules
• upgrade biogas to biomethane in engineered systems in a static or mobile unit at the place of production
• store upgraded biomethane
• fuelling vehicles at the site of production
• injection of biomethane to the national grid

Do you agree that the proposed activity limits are appropriate?

If no, please explain your answer.

Summary of responses to question

• yes – 3
• no – 3
• did not respond – 1

Summary of comments received

Of the 3 respondents who answered ‘no’ to this question, these are a summary of their comments:

• 3 respondents raised concerns on the viability of injecting biomethane into the national grid
• most stated a preference for the site to be able to generate their own energy on site, but this is restricted as spark engines are not allowed
• 2 mentioned the lagoon infrastructure is not always available to demonstrate that a lagoon meets the criteria
• 2 stated the standard rules is too limiting because:
  • considerations should be made for mobile or modular storage
  • the volume stated is set too low which could limit eligibility to those with smaller lagoons, or new builds

Our response

Injecting biomethane into the national grid is an option within these standard rules set, but it is not a requirement. Under these standard rules you can also fuel vehicles at the site of production. This rule set adds to the suite of permits for on farm and is focused on the recovery of methane and upgrade predominantly for use in tractors. This permit did not intend to allow combustion of biogas or biomethane in a spark engine for the generation of heat and power.

We have not included specific combustion units as this would necessitate increasing set back distances. Other standard rules are available if the operator can comply with the conditions. We will review this again but it will require a further consultation period.

Within the existing anaerobic digestion (AD) standard rules permits it would be permissible to collect residual biogas from lagoons and tanks storage and upgrade for grid injection. 

Lagoons need to meet a required specification and the operator should make sure this is met. Slurry stores built after 1991 should be compliant with the silage, slurry and agriculture fuel oil (SSAFO) regulations. As such they hold a minimum of 4 months storage. Stores built in 1991 or earlier are SSAFO-exempt, providing they are not posing an environmental risk.

Operators of existing sites must use a chartered engineer to carry out a detailed survey of the lagoons where it has not previously been validated to industry recognised standards. Slurry stores built after 1991 should be SSAFO-compliant. As such they hold a minimum of 4 months storage

Stores built in 1991 or earlier are SSAFO-exempt and may be appropriate to use, providing they do not pose an environmental risk (such as leaking). Therefore there remains a requirement to assess these. Please refer to our appropriate measures guidance or industry guidance CIRIA 736 or 759. Where they are unable to meet any standard it is unlikely that a supplier would risk fitting such a system.

Theses standard rules are limited by volume and restricted to static or fixed infrastructure because we believe this will limit the risk of pollution. Anything bigger would need further risk assessment. The consultation responses did not present sufficient evidence for us to amend these volumes or present risk management alternatives.

Question 2. Operating techniques to control explosive atmospheres.

The draft rules set out minimum requirements to prevent incidents from over pressure and minimise explosive atmospheres and if they occur, to limit their duration and ability to cause pollution and harm to human health.

Do you agree with the proposed operating techniques to control explosive atmospheres?

Please provide additional comments to support your answer if needed.

Summary of responses to question

• yes – 5
• no – 1
• do not know – 0

Summary of comments received

• One respondent told us that costs may be inhibitory and need to be proportionate.
• One respondent reiterated their concern about the limiting of the use of spark engines.
• One respondent raised the issue of methane buildup in areas on site (for example storage where biogas is not being collected) that are not under the same level of monitoring and may not have been assessed under the dangerous substances and explosive atmospheres regulations (DSEAR).

Our response

The requirements and costs are consistent with other standard rules for managing biogas. The costs are:

• permit application – £2,641
• minor variation – £792
• normal variation – not applicable
• substantial variations – not applicable
• transfer application – £2,529
• surrender application – £2,356
• annual subsistence – £1,585

Spark engines are outside the scope of this standard rules. These standard rules are not aimed at a combustion activity but a collection and treatment process. This would place restriction on distance criteria. There are other standard rules sets or bespoke permit options to cover combustion.

When managed appropriately there should be no build-up of biogas elsewhere on the site. There is limited storage on site and no other permitted material which could generate biogas. These rules require a DSEAR assessment by a qualified person and therefore this risk is be managed. We have also limited the amount of biogas stored on site to minimise risk.

There should not be any area where gas is building up. This is the purpose of the DSEAR assessment. A qualified person will be able to identify the risks and the optical gas imaging leak detection and repair (OGI LDAR) monitoring will give assurance about this.

Question 3. Operating techniques to control air pollution.

Given the activities are restricted to collection, storage and upgrade of biogas to biomethane from slurry and manure or digestate, we consider that the draft rules will adequately control pollution from emissions of biogas and its components or biproducts of combustion by a standby flare.

Do you agree with the proposed operating techniques to control air pollution?

If no, what alternative or additional controls do you think are required?

Summary of responses to question

• yes – 2
• no – 1
• do not know – 3

Summary of comments received

• One respondent commented there is a concern that the techniques specified are out of date and the rules need to reflect the range of potential use for the gas. Smaller systems on rural sites pose limited risk of damage from emissions. There is a need to allow a broad range of forms of gas such as for space heating, generating cool for cold stores and use in milk cooling as well as for heating local houses and on farm vehicle fuel.
• Unclear what is meant by a ‘standby flare’. It was proposed that the use in boilers would be more appropriate.
• Note that the methods laid out in BS EN 15446 may rule out some kinds of leak detection devices.
• Concern over the type and frequency of monitoring that would be required, specifically odour monitoring. The value of monitoring should be reviewed to make sure it is of benefit and meets the needs of the permit without undue obstacles to the farming community and only when there are odour concerns due to the proximity of sensitive receptors. Although there is appreciation that standard rules permit is meant to be designed to reduce the complexities and make a process of administering more straight forward by categorising however there is limited ability to utilise this captured gas more effectively onsite that is not totally understood by the consultation documents.
• Whilst LDAR and fugitive emissions monitoring should be sufficient, provided they cover any waste storage that is not connected to the biogas system, not just stores where biogas is actively being collected.

Our response

The respondent commenting on the appropriateness of the techniques offered no further information nor offered an alternative.

These rules are not intended for a combustion activity. There are other standard rules sets or bespoke permit options to cover combustion.

The purpose of the ‘standby flare’ is to prevent the emissions of unburnt raw biogas to atmosphere in the event of surplus gas, emergency or maintenance. The limits of using auxiliary standby flares are stated in table 2.1 of the draft standard rules as being “limited to using auxiliary standby flares burning excess biogas in emergency conditions or during maintenance”. But should not be used to routinely combust biogas.

We believe that the use of a flare will be very minimal during an over pressure event or emergency. Therefore the use for boilers would be rare. Other AD standard rules are available for medium combustion engines and generators.

We acknowledge that referencing BS EN 15466 in table 3.3 potentially excludes the use of OGI methods, therefore we have updated to use the wording from the appropriate measures for biological waste treatment (section 11.9) as follows:

• sniffing using organic compound analysers and bag sampling, carried out to EN15446 standards
• optical gas imaging using hand-held cameras to enable visualisation of gas leaks

We have reviewed the odour monitoring requirement and have replaced it with an odour management plan requirement. We will clarify the intention of this permit.

Question 4. Operating techniques to control water pollution. 

The draft rules set out minimum requirements to prevent incidents and any pollution caused by over topping and leakage to ground water or surface water.

Do you agree with the proposed operating techniques for water pollution?

If no, please explain your answer. 

Summary of responses to question

• yes – 6
• no – 0

Summary of comments received

All respondents agreed with the proposal for operating techniques for water pollution, with the following comments:

• One respondent commented the measures need to reflect the level of risk and the volume being treated per day. On farm AD can help protect water courses by improving management of slurry and manure. The use of AD systems on food and beverage processing sites will reduce the external impact on water treatment plants and ensure a more circular use of resources which should be welcomed by the Environment Agency.
• One respondent stated that leak detection needs to be required, but consideration must be given for the extra cost of retrofitting leak detection on existing stores and lagoons.

Our response

All food and drink sites will have AD as a directly associated activity and that will be reflected in varying the dominant permission. This standard rule is proposed specifically for agriculture premises or anaerobic digestion operations where digest is stored. The standard rule will be edited so it does not apply to food and beverage sites nor any other industry. Other rules sets and bespoke options are available.

The appropriate measures guidance addresses existing sites and stipulates underground pipe work or ducting and drainage needs to be monitored to make sure there is no leakage. Underground tanks should have secondary containment with an implemented method of inspection and leakage detection as a minimum. We will amend the permit to make this clear. We are not compelling requiring farmers to undertake these activities but trying to enable these.

Question 5. Further comments.

Please provide any other comments you wish to make about the draft rules.

Other comments made on the draft rules included:

• In principle, provision of a standard rules permit is welcomed as it provides a solution to prevent a potential release of emissions which could be harnessed for a fuel and help with decarbonisation.

• Recommend changing units from tonnes to m3 or scmh in line with industry.

• Consultation focussed on covered lagoons, rather than a range of systems that will be suited to the diverse needs of smaller farmers.

• Modular AD and Continuous Stirred tanks need a regulatory position, with a formalised exemption.

• The 5,000m3 lagoon/tank volume limit is unworkable. Multiple farms already exceed this volume.

• Clarity is required on gensets and how they fit into sites and permit boundaries.

• Fitment of covers to lagoons should be allowed where the cover’s minimum requirements for safe deployment and operation are met, and that new build/purpose build gas capture lagoons show that correct building and design practices have been followed.

• 2 respondents raised concern around the cost implications for farmers, to encourage the right behaviours.

• Some of the lagoons that would have the potential for gas capture may have been constructed a number of years ago, with the appropriate protections, and will often have a lack of paperwork to demonstrate compliance. Retrospective confirmation of building methods for earth banked lagoons is typically not possible. Additionally, these are not designed as pressure vessels so pressure testing is not required.

• Current herd sizes may already exceed the specified limit of 5,000 m3. Examples were provided.

• Very close similarity to standard rules permits for anaerobic digestion facilities, but inconsistencies in reference to storage vessels as tanks or lagoons or both, and some of the techniques seem to have limited relevance.

• Query whether secondary containment for storage tanks is for above ground slurry storage, or for storage of other liquid items on site, for example an imported waste. Note, above ground slurry storage does not typically have secondary containment, even on new installations.

• Covers/gas equipment could be tested for leaks at pressure as part of LDAR regime, though slurry lagoons/tanks are not testable.

• Query over the use of determining volume being visual or via flow meters.

• Requirement for odour testing seems excessive and a financial burden, especially where there will be other sources of odour in the vicinity.

• Concern over the financial implications of implementing the requirements, namely odour testing, pressure testing of lagoons/slurry stores, lagoon CIRIA verification reports.

Our response

• With regards the units of reporting the units presented allow the site to be in line with the control of major accidents hazards (COMAH) reporting requirements in tonnes.

• This consultation focussed on covered lagoons, rather than a range of system that will be suited to the diverse needs of smaller farmers. Other rule sets are available for smaller AD sites. See SR2021 No 7: anaerobic digestion facility, including use of the resultant biogas – waste recovery operation.

• Modular units would be difficult to risk assess for the reasons above. This is a site-based permit where the risks can be assessed and monitored.

• The 5,000m3 lagoon or tank volume limit is unworkable. Multiple farms already exceed this volume. Working with technology providers and on advice from agricultural colleges the 5,000m3 lagoon or tank volume limit was assessed to be sufficient. However, we will reassess and are minded to modify this.

• Regarding gensets this standard rule was written to allow passive collection and upgrade of biogas to biomethane only. This standard rules set is not a combustion based authorisation and therefore gensets and generators fall outside the scope of this standard rules set. Other standard rules are available. We were not originally made aware that this would be the case and therefore consulted and wrote these rules to exclude generators. If we were to include combustion units distance criteria and monitoring will apply for the engines. We have aimed to construct the permit with few restrictions on location.

• Fitment of covers to lagoons would be allowed where the requirements for safe deployment and operation are met, and that new build and purpose built gas capture lagoons show that correct building and design practices have been followed. Respondents (2) raised concern around the cost implications for farmers, to encourage the right behaviours. We recognise that to bring lagoons up to a safe and effective operation standard may require investment at some locations. This is a capital expenditure issue for farms wishing to deploy this technology. The cost of the permit is minimal.              
  An assessment of fit for purpose would need to be undertaken prior to installing such a system on an existing lagoon and it unlikely that any installer would carry out such an installation without these checks and assurances in place. Some of the lagoons that would have the potential for gas capture may have been constructed a number of years ago, without the appropriate protections, and will often have a lack of paperwork to demonstrate compliance. Retrospective confirmation of building methods for earth banked lagoons is typically not possible.

  Lagoons need to meet a required specification and the supplier and operator should make sure this is met. Operators of existing sites must use a chartered engineer to carry out a detailed assessment of the lagoons where it has not previously been validated to industry recognised standards appropriate measures. Food and drink sites that are permitted will have to include this as a directly associated activity if permitted by the Environment Agency.

  Existing anaerobic digestion standard rules permits already have the ability under standard rules to install storage and upgrade of biogas to biomethane and install such covers.  

• As some of the measures to control risk are similar to other AD permits for managing gas it makes sense to repeat these. We will check for inconsistency, but these are slightly different to AD plants and combustion sites.

• Requirement for odour testing seems excessive and a financial burden, especially where there will be other sources of odour in the vicinity.

  We have reviewed these requirements and amended where necessary. We agree for this standard rules that annual monitoring of odour concentration to BS EN 13725 standards is not required and will amend the standard rules accordingly. We may require odour concentration monitoring resulting from odour issues as part of an operator’s odour management plan.

• Query whether secondary containment for storage tanks is for above ground slurry storage, or for storage of other liquid items on site, for example an imported waste. Note, above ground slurry storage does not typically have secondary containment, even on new installations.

• Covers and gas equipment could be tested for leaks at pressure as part of LDAR regime, though slurry lagoons and tanks are not testable. Covers and gas equipment could be tested for leaks at pressure as part of LDAR regime, though slurry lagoons or tanks are testable with the use of optical gas imagining.

• Operators will need a methodology to measure flow rates to comply with the permit limits.

• Regarding the concern over the financial implications of implementing the requirements, namely odour testing, pressure testing of lagoons or slurry stores, lagoon CIRIA verification reports. We have amended the requirements for odour monitoring. However, all lagoons should have complied previously with SSAFO regulations based on CIRIA requirements. To reduce risk of environmental impact the lagoon construction must be able to meet a standard.

5. Responses to the generic risk assessment: question 6

Question 6. The draft rules are accompanied by a generic risk assessment.

Do you agree that the generic risk assessment adequately covers the risks associated with the capture, treatment and storage of biogas from lagoons and tanks?

If no, please explain your answer.

Summary of responses to question

• yes – 3
• no – 1
• do not know – 1

Summary of comments received

• There should be more encouragement of circular solutions that use bio-residues to produce clean energy to replace fossil fuels on farms and in rural areas. The Environment Agency and policy makers must support rather than overregulate smaller-scale production of biogas for local heat and fuel use.
• The new layout for risk assessments (that is as a list of text, rather than a colour coded table) introduces possible confusion for those already using the old risk assessments. The text-based risk analysis also makes it harder to determine the weight of risks.
• The risk assessment for fire and explosion is also not sufficient, as it inadequately assesses the risk to the facility and the possibility for fatalities. It would be better to be omitted entirely, leaving this assessment to be carried out at a site level under the requirements of DSEAR. It is appropriate to insist that a DSEAR assessment is carried out, and that it must be undertaken by competent persons. It is not appropriate to include something labelled as a risk assessment of explosion or fire in the current level of detail which is neither suitable nor sufficient. As well as providing a false sense of security to operators and putting the Environment Agency at legal risk in the event of an incident, the risk assessments of harm to people represent a regulatory overreach into affairs better managed by other mechanisms (the Health and Safety Executive (HSE) and other safety specific rules & regulations).

Our response

We are supporting by putting in place a standard rule. The conditions of the standard rule is proportionate and based on appropriate measures for biowaste. The development of the Green Gas Support Scheme is not within the Environment Agency’s remit.

All biogas plants present some risk and it is our regulatory duty to make sure these operations are carried out safely and with the right environmental protection whilst supporting development of future energy supply. We will review with HSE. However, the risks under our remit are not only to the environment.

6. Responses to the business impact: questions 7 to 10

Question 7. What staff roles are responsible for preparing permit applications and supporting Environment Agency compliance assessment activity for permitted sites (for example, technical specialist, manager, senior official)? 

Summary of comments received

5 respondents answered this question, naming the following staff roles: -

• Technical specialist
• Operator
• Senior official
• Environmental assessor
• Consultant or advisor
• Engineering team
• Gas operations team

Question 8. Will you incur any third-party monetary costs to prepare a permit application (for example, hire consultants, access external advice)?

Summary of responses to question

• yes – 3
• no – 0
• do not know – 1
• not answered – 2

Summary of responses to question

All respondents that answered yes named permitting and compliance consultants as the third party costs.

One respondent estimated the costs for consultants for the planning and permitting applications to be between £20,000 to £30,000. Planning applications are not within the remit of the Environment Agency. 

The development of standard rules should reduce the cost of permit application as the risk assessment has been undertaken by the Environment Agency. 

For the reasons previously stated, it is likely that as it stands the permit would only be eligible for farms with smaller lagoons or stores. Therefore, they are unlikely to have significant members of staff or technical capability to complete the applications or ability to employ a permanent member of staff, unless the gain from gas generation was significant to add value. It is expected that most applying would have to employ a contractor to complete the application. It has been suggested that there may be some Environment Agency provision or work with the AD sector to provide sufficient guidance to farmers.

Question 9. How many hours do you estimate it will take you to prepare a standard permit application?

Summary of responses to question

There were 4 responses to this question. Answers ranged from 8 to 120 hours, the average was 65 hours.

This appears to be excessive as applying for a standard rules permit should be easy as rules and exclusions apply. Either you can meet the rules set or you can not.

Question 10. How many hours do you estimate it will take you to provide support for an Environment Agency compliance assessment visit (this may involve preparing for the visit, accompanying an Environment Agency Officer and any follow-up actions)?

Summary of responses to question

There were 3 responses to this question. Answers ranged from 8 to 40 hours, the average was 26 hours.

Where the operator is compliant with the rules set and records are maintained, 40 hours for one visit appears excessive.

7. Next steps

The responses we received have provided information that supports us in producing a standard rules for the capture, treatment, and storage of biogas from lagoons and tanks. We will now review the draft permit and generic risk assessment to produce final versions. We plan to publish them on GOV.UK in summer 2024.

If you wish to follow up on your responses or have questions relating to this consultation response document, please email wastetreatment@environment-agency.gov.uk and include ‘Standard rules consultation number 27’ in the subject.

8. Annex

List of consultation respondents (by organisation name):

• Anaerobic Digestion and Bioresources Association
• Bennamann Ltd
• Foodchains
• Marches Biogas
• Members of the public (2)
• The Association for Renewable Energy and Clean Technology: REA