Your permit condition for odour management

How your environmental permit tells you to manage odour pollution.

The odour condition

The standard odour condition in an environmental permit says:

Emissions from the activities shall be free from odour at levels likely to cause pollution outside the site, as perceived by an authorised officer of the Environment Agency, unless the operator has used appropriate measures, including, but not limited to, those specified in any approved odour management plan, to prevent or where that is not practicable to minimise the odour.

Your permit condition may also say:

The operator shall:

(a) if notified by the Environment Agency that the activities are giving rise to pollution outside the site due to odour, submit to the Environment Agency for approval within the period specified, an odour management plan which identifies and minimises the risks of pollution from odour;
(b) implement the approved odour management plan, from the date of approval, unless otherwise agreed in writing by the Environment Agency.

Your permit may have an odour condition that’s not worded the same way as this, depending on its age. For example, the permit may say that you must not cause nuisance, annoyance, offensive odours, interference with amenities, pollution and so on.

The Environment Agency will interpret the terms referred to in your permit to mean pollution.

Levels likely to cause pollution as perceived by an authorised officer

Before recording that you’ve breached the odour permit condition, Environment Agency officers need to:

  • personally perceive odour outside of your site boundary
  • decide that the odour is caused by your site

Officers will assess whether the odour has the potential to cause offence to others, even if they are not offended themselves. They will consider the likely impact of odour they detect on individuals in the nearby community, including people who may be more sensitive or vulnerable.

Officer monitoring is described in more detail in the section on assessing the impact of odour.

Outside the site

This means beyond the permitted boundary that is stated in your permit.

While odorous emissions may be present, there’s only odour pollution when people are there to detect it.

Most odour investigations are done in response to odour reports from members of the public. However, officers do not need to detect odours at the location of the original reporter. Officers’ investigations may take place under changeable wind direction and dispersion conditions.

If officers detect odour outside the site, which they can attribute to activities on the site, they can use this to assess compliance with the odour permit condition. For example, the character of the odour may mean that it relates to a certain type of activity.

Appropriate measures

For appropriate measures, there is overlap between ‘best available techniques (BAT)’ for installations and ‘appropriate measures’ for some waste operations. This guidance uses the term ‘appropriate measures’ to cover both sets of requirements.

Not all methods for controlling odour in BAT conclusions apply to all sites. You must use methods that are relevant to and cost-effective at your site. The most effective odour controls may not be the most expensive options and may improve your site operations.

Unless methods or emissions limits are specified in BAT conclusions or standard rules permits, appropriate measures is a flexible standard which requires measures that are proportionate to the risk of pollution. This means you may be required to do more if your activities cause or could cause serious pollution. You may need to propose further restrictions on:

  • material types
  • inventory controls
  • process controls
  • containment
  • abatement

If the Environment Agency thinks your activities will lead to serious pollution, they may reject your permit application.

Besides the odour permit condition, you will have a general management condition in your permit which requires you to apply all appropriate measures to control pollution. This condition applies even if you do not cause pollution.

The role of an OMP

An OMP is an operational document that:

  • forms part of your management plan
  • is written by you, or on your behalf
  • is easy to understand and available to your staff to guide their decisions and actions
  • must include or refer to an odour risk assessment
  • specifies the measures you will take to prevent odorous emissions and impacts, or to minimise them if that’s not possible

If the Environment Agency considers that your activity presents a high risk of causing odour pollution, you must submit your OMP with your permit application for approval.

Check the guidance on how to control and monitor emissions for your environmental permit for activities considered high risk that require an approved OMP.

Standard rules permits are considered low risk. Odour control measures for sites with standard rule permits are described in their management systems. But if these sites cause odour pollution, they may be required to submit an OMP for approval.

Check the section on writing your odour management plan for:

  • what your OMP must include
  • standards for how OMPs are approved

The Environment Agency may charge for reviewing your OMP in line with its charges guidance.

If you need to submit an OMP, you must provide one which is satisfactory and can be approved. The approval process will be delayed until you provide an OMP with the correct information.

Your permit application or variation may be refused if you do not submit a satisfactory OMP with acceptable measures for controlling odour pollution.

When the Environment Agency approves OMPs, they will agree the scope and suitability of key measures in principle. However, this does not confirm that the details of equipment specification design, operation and maintenance are suitable and sufficient. That is your responsibility.

You must keep the current version of your OMP available for inspection, whether or not it has been approved.

You must always use appropriate measures to control odour pollution from your activities. If you cause odour pollution, the Environment Agency will assess whether you are using appropriate measures, including those specified in your OMP.

If odour pollution is happening and you are not taking appropriate measures, you may be breaching your permit condition, which is a criminal offence.

The Environment Agency may reconsider whether your OMP is still satisfactory if:

  • your activities cause odour pollution
  • deficiencies in your OMP become apparent

If the OMP is no longer satisfactory, the Environment Agency will highlight problems and require you to submit a revised OMP for approval under the permit condition.

If you do not correct these deficiencies and odour pollution happens, it will be more difficult for you to demonstrate that you were using appropriate measures in any later enforcement action.

An OMP cannot cover every situation. Even if you are implementing an approved OMP, odour pollution may still happen. This may show that more appropriate measures are needed. This could include restricting activities and reducing stocks of odorous materials. You need to implement and record these additional measures in your OMP.

The Environment Agency will normally give you a reasonable amount of time to make improvements. However, they may require urgent action if:

  • serious odour pollution is happening
  • pollution is caused by something that you should have prevented

Odour risk assessments

Risk assessments:

  • assess and prioritise odour sources within a site
  • guide the approach to odour control from a site
  • assess the potential for activities to cause serious pollution

Your risk assessment needs to consider the impacts and causes of any past or current odour pollution incidents. These indicate important risks and influence corrective action.

You need to anticipate the risk of odour pollution to make sure you can apply appropriate preventative measures.

The Environment Agency will assess whether your odour risk assessment is realistic and appropriate measures are proportionate. They may reject your OMP if they think:

  • you have not considered all risks
  • you have been too optimistic in your assessment of risks

Check how to write your risk assessment in the writing your OMP section.

Odour permit compliance assessment

The Environment Agency uses a 3-part test to assess odour permit compliance.

  1. Is there odour pollution beyond your site boundary?

  2. Is odour pollution due to emissions from your site?

  3. Are you taking all appropriate measures to prevent odour pollution? Or, where that is not practicable, to minimise odour pollution?

What to expect

  1. If there is no odour pollution beyond the boundary of your site, you are complying with your odour permit condition. You will still need to comply with other permit requirements to make sure odour remains under control, such as effective process monitoring and control.

  2. If odour is reported, the Environment Agency will carry out an initial office-based assessment to understand the degree of pollution.

  3. Environment Agency officers may conduct an inspection, depending upon available resources and the apparent degree of odour pollution.

  4. If officers observe the odour offsite, and they think it is caused by your activities, they will assess whether you’re taking all appropriate measures. Some appropriate measures assessments may require other investigations or consultations with experts.

  5. The officer will then complete a Compliance Assessment Report in line with waste operations and installations: assessing and scoring environmental permit compliance.

You will not breach your odour permit condition if you are using appropriate measures. The Environment Agency will classify each incident by severity, regardless of whether there has been a permit breach or an inspection.

If you are not complying with your odour permit condition

The Environment Agency may:

  • give you advice
  • require you to submit a new or revised OMP
  • give you a score in line with the compliance classifications scheme
  • serve you an enforcement notice, which requires you to take specific steps to remedy the odour pollution (and return to compliance with your permit) by a specific date
  • serve you a suspension notice – this means you must temporarily stop carrying out specific activities, such as receiving waste, until you have removed the risk of pollution
  • prosecute or apply a civil sanction if it’s in the public interest
  • agree an enforcement undertaking
  • change your permit conditions, including restricting activities or quantities
  • revoke (cancel) the permit if necessary

Serious odour pollution

The Environment Agency will assess odour pollution impacts using the methods and approaches described in the assessing the impact of odour section.

They will characterise odour pollution incidents from permitted activities as serious pollution when there are:

  • serious effects on human senses
  • major effects on the value of amenities (activities, events or places)
  • or significant effects on human senses or amenities

These impacts correspond to Category 1 and Category 2 odour pollution incidents. These are described in the classification of odour pollution incidents by severity section. Minor amenity impacts may also be classed as serious if they continue or are repeated over an extended period.

Assessments of serious pollution are made on a case-by-case basis. These judgements help inform decisions about our assessment of appropriate measures and any potential enforcement action. The Environment Agency will also consider whether:

  • the causes of odour pollution can be corrected quickly
  • whether any solutions you suggest are likely to be long-lasting

Serious pollution can happen where there are no additional appropriate measures you can take. If this happens, the Environment Agency will review the situation carefully and may consider:

  • placing additional restrictions
  • suspending your permit
  • revoking the permit, in part or in full

There does not have to be a breach of the odour permit condition before the Environment Agency uses these options.

The Environment Agency may require more information or refuse a permit application if they think operations on site will result in serious odour pollution.

Permit reviews

The Environment Agency sometimes reviews sector permits. This is to check the permits are up to date with the latest regulations and environmental standards. You will be told if permits for your sector are being reviewed and what that means for you.

The Environment Agency can also review your bespoke permit if you are not complying with it or are causing pollution. You may have to apply for a change to your permit, or you may be given new conditions.

If you hold a standard rules permit, you may be required to apply for a bespoke permit if the risk of odour pollution is greater than your standard rules risk assessment.

For more on how you’ll be regulated

There’s also general guidance on how you’ll be regulated: environmental permits.