Control and monitor emissions for your environmental permit
How you must control and monitor emissions from your activities that may cause pollution.
If you’re applying for a new permit or already have a permit, read this guide to find out:
- how to monitor emissions from your activity
- how to operate within any emissions limits that you might get in your permit
- what to do if the Environment Agency tell you that you’re causing pollution
- what to do if you need to write a plan for emissions, odour, noise and vibration or pest management
Use your risk assessment to help you identify emissions from your site. Read how to do a risk assessment if you haven’t done one yet.
You must show how you will control your emissions in your management system. If you have a waste, mining waste or installation permit you may need to write plans to explain how you’ll deal with emissions, odour, noise and vibration or pests. These plans will become part of your overall management system.
Most conditions are objective-based: the Environment Agency defines what the objective is but it’s up to you how you meet an objective. For example, an objective at a composting site could be to use measures to make sure odour doesn’t cause pollution outside your site’s boundary.
This guide will help you work out how to meet an objective (what the ‘appropriate measures’ you should use are). You should also follow the specific technical guidance for your particular type of activity or for the type of pollution (for example, odour).
Conditions will be prescriptive if there’s a high risk from your activity or site that needs to be controlled. In these cases the condition will tell you exactly what you need to do, for example by:
- stating the equipment you must use
- defining a specific emission limit you must comply with
- telling you to implement a plan which the Environment Agency has approved
You must follow all the conditions in your permit or you could be breaking the law. If you cause pollution the Environment Agency may suspend or cancel your permit.
You must follow the conditions in your permit which tell you to prevent or minimise pollution. Pollution is any emission as a result of your operations which may:
- be harmful to human health or the quality of the environment, for example ecosystems on land or water
- cause offence to a human sense, for example hearing (apart from standalone surface or groundwater discharges)
- cause damage to property
- damage or interfere with amenities or other uses of the environment
Point source emissions
Your permit may set limits on emissions to air, water or land from ‘point sources’ (emissions from one or more set points), for example:
- discharges to infiltration systems (drainage fields)
- exhaust gas from a boiler stack
- waste water or treated sewage discharge from an effluent treatment plant outlet pipe
There may be more than one type of emission from a specific point, for example an effluent treatment plant outlet pipe might release treated effluent and surface water drainage.
Emissions that don’t have set limits
There are some types of emission that may cause pollution but don’t have set limits in permit conditions. In permits these are called ‘emissions not controlled by emissions limits’ or ‘fugitive emissions’.
For waste, mining waste and installations these include:
For water discharge activities and groundwater activities there may be things in the discharge that don’t have set limits in your permit.
You must control these emissions and make sure they don’t cause pollution.
If your risk assessment shows you have a risk of these types of emissions you may need to provide an emissions management plan when you apply for your permit to demonstrate how you’ll control them.
If you cause pollution from these types of emissions but don’t already have an emissions management plan, the Environment Agency may ask you to submit a plan to them.
Dust, mud and litter
If you have a waste, installation or mining waste permit you must take the following measures to prevent the spread of dust, mud and litter from your site:
- carry out operations inside buildings whenever possible
- erect litter fences around the site
- cover vehicles, skips or vessels unless they’re empty
- enclose conveyors and minimise drops, or use pneumatic or screw conveying
- install filters to vents on silos, building extractors and conveying systems
- surface or pave your roadways, eg with tarmac, and make sure vehicles keep to paved roads
- regularly clean and dampen roadways and vehicle wheels
- keep points of access to your site from public roads to a minimum
- use water-filled troughs to slow trucks, wash wheels and keep roadways damp
- clean spillages with vacuum cleaners rather than washing down
- clear your site of litter and mud at the end of each working day, unless it’s impractical or unsafe to do so
- plant grass or trees on open ground to reduce dust (hydro-seeding can rapidly establish vegetation on waste tips, slag heaps or other apparently infertile ground)
During high winds, you must also avoid activities that could lead to the spread of litter, dust or mud, for example unloading waste from vehicles outside buildings.
You must also avoid positioning stockpiles outdoors, or leaving them uncovered.
If you can’t avoid positioning a stockpile outdoors, or leaving it uncovered, you should take steps to prevent material escaping from them, like using sprays, binders or windbreaks. You should control the moisture content of the material in the stockpile, and place stockpiles in the direction of the prevailing wind.
Emissions to water
Make sure that your site surfaces, eg roofs, hard standing, working areas, any containment structures required by your permit, eg bunds or other secondary containment measures, and your site drainage infrastructure will prevent pollution to surface water and groundwater.
Consider collection capacities, surface thicknesses, strength and reinforcement, falls, materials of construction and permeability.
You must make sure any rainfall collection systems are kept separate from areas of the site which are or may be contaminated.
Make sure your surfaces and containment or drainage facilities are resistant to spilled chemicals. Your management system must include a plan about how you will inspect and maintain your surfaces and containment facilities.
The following are needed to prevent contaminated run off polluting groundwater or surface waters:
- a waterproof surface
- spill containment kerbs
- sealed construction joints
If you don’t already have these things in place you must have a plan to show how and when you’ll put them in place if they’re needed. You may need to use extra measures to control risks in the meantime.
Your permit may say you must have a connection to a sealed drainage system.
A sealed drainage system prevents water escaping from your operational area, and means any liquid used in your process will be stored in the system and collected for disposal elsewhere.
- collect any liquid that passes through your drainage system in a sealed sump (collection pool), unless you have a permit to discharge the liquid
- dispose of collected liquid through a treatment facility or have it collected by a specialist waste disposal company
If your operation causes pollution, you must:
- clean up the pollution as soon as possible
- stop the activity until you have changed your operation to prevent pollution in future
- tell the Environment Agency (your permit will tell you how to do this)
Leaks from containers
You must prevent leaks or accidental release of liquids that could cause pollution from tanks, sumps, containers and bunds.
Bunds are walls built around tanks to capture anything that leaks from them.
Piping and drainage
You must design your site so that leaks from underground structures are prevented and any leaks can be detected quickly.
You must keep a record of the route of any underground drains or pipework on your site.
If you use oil in your operations you must fit and maintain oil separators to surface water drainage systems to prevent discharges being contaminated by oil.
You don’t need to follow this guidance on bunding if your storage tanks, treatment tanks and underground pipe-work hold, treat or transport sewage at sewage treatment works or sewerage networks.
You must provide containment (bunding) for underground pipework, sumps and storage vessels. You may also need to fit a leak detection system, for example if you’re carrying out your activity in a groundwater Source Protection Zone.
You must keep a list of any underground sumps or storage vessels.
Your sumps and bunds must be:
- resistant to any materials you’re going to store in them
You must make sure sumps and bunds don’t become contaminated or blocked as this may cause them to leak.
- check that sumps and bunds are working correctly, eg that there are no cracks
- hydraulically test any sump or bund if you’re worried it isn’t working correctly
- fit a high-level probe to any sumps or bunds that you can’t check with an alarm to alert you before waste begins to escape containment
Your bunds must also have a capacity larger than both of the following:
- 110% of the largest tank the bund is protecting
- 25% of the combined volume of all the tanks the bund is protecting
Use the maximum volume that a tank can physically hold when calculating capacity, don’t use the volume a tank is designed to hold.
Your bunds must also:
- have no outlets (eg drains or taps)
- drain to a blind (completely enclosed) collection point
- have self-contained pipework that is separate from the container pipework
Your bunds must have tanker connection points within the bund. If that’s not possible, the tanker connections points must be contained to capture any leaks.
If you need to use your bund to contain a leak you must make sure it’s emptied to restore maximum capacity.
Storage areas for intermediate bulk containers, drums, bags
You must bund or kerb any area where environmentally harmful substances are stored (eg acids, chemical solvents, milk, lubricating oils and styrene).
You must store substances separately if it may be risky to store them too near each other, for example because they’re flammable or if 2 substances spilled and mixed could cause an explosion or harmful fumes.
Don’t use plastic intermediate bulk containers (medium-sized containers that can be moved easily and are made out of plastic or metal) to store flammable materials.
You must also:
- locate storage areas away from watercourses, sensitive groundwater areas such as Source Protection Zone 1 (SPZ1), unprotected drainage systems and sensitive boundaries, eg near areas where people live or nature reserves
- clearly mark your storage areas, and any containers and packages in them
- define the maximum storage capacities for each of your storage areas and containers and stick to them
- store containers, including empty containers, with lids, caps and valves secured and in place
- inspect your containers, drums and small packages at least once a week to check they’re not damaged or leaking and put a procedure in place to replace or repair damaged or leaking containers
Volatile organic compounds (VOCs)
Volatile organic compounds (VOCs) are substances with low boiling points that evaporate from solids or liquids used in industrial processes, for example formaldehyde evaporating from paint, or benzene from fuel.
You must take the following steps to prevent emissions of VOCs:
- enclose any containers on your site
- fit equipment to capture VOCs on any vents on your site (eg scrubbers or filters)
- install sealed transfer (vapour balance) systems
- use sub-surface filling via (anti-syphon) filling pipes extended to the bottom of the container
- use floating roof tanks and bladder roof tanks
- use tank vent systems that minimise breathing losses, for example pressure/vacuum valves, and fit knock-out pots where necessary
If VOCs are released on your site, you must counter the release with techniques like adsorption (using a substance like a solid or liquid to absorb another substance, like a liquid or gas) or condensation (cooling or compressing a liquid to its saturation point) to capture the VOCs.
You must also prevent vapour and fluid emissions by:
- managing inventories
- preventing leaks from any pipework or fluid transport systems
- using white paint, insulation and active temperature controls to reduce the temperature in any storage tanks
The Environment Agency may include further specific steps that you must take in your permit.
You must prevent or minimise odour if you have a waste, mining waste or installation permit. To do this you must:
- avoid using raw materials that are likely to cause odour, like biodegradable materials
- minimise quantities and storage times for biodegradable materials that you can’t avoid using altogether
- don’t expose biodegradable materials to high temperatures or air
- avoid operations that cause smells
- enclose smelly materials and activities in buildings or containers
You must respond to any complaints or concerns by stopping activities that cause odour until you’ve developed procedures to control the odour.
Written odour management plan
You must write an odour management plan that explains how you will prevent or minimise odour if you’re aware that your site creates odour problems, or if you carry out any of the following activities:
- landfilling biodegradable waste
- household, commercial and industrial waste transfer station
- composting in open windrows
- composting in vessels
- mechanical biological treatment
- sewage sludge treatment
- clinical waste treatment
- animal carcass incineration
- pet cemetery
- mobile plant for landspreading, the treatment of land for land reclamation, restoration or improvement and landspreading of sewage sludge
- anaerobic digestion
- mobile plant for the treatment of waste soils and contaminated material, substances or products manufacture, use or recovery of compounds containing sulphur, ammonia, amines and amides, aromatic compounds, styrene, pyridine and esters
- abattoirs and renderers
- food production involving any form of cooking or heating and brewing
- distilling or heating tar or bitumen
If you’re applying for a bespoke permit for one of these activities you will need to submit your plan with your application.
You can use the template odour management plan to help you decide what to include in your plan.
If you cause odour pollution but don’t already have an odour management plan, the Environment Agency may ask you to submit a plan to them.
Noise and vibration
Noise pollution is unwanted sound that causes disturbance and can affect the quality of life of humans and wildlife.
You must prevent or minimise noise and vibration if you have a waste, mining waste or installation permit. To do this you must:
- factor noise levels in to your plant design, and your plans for maintaining and operating your plant
- position noisy operations (that increase the noise in any area above background noise) away from delivery or vehicle routes
- use noise reduction equipment like balancing fans and fixing loose covers on noisy operations
- isolate noisy operations through measures like acoustic enclosures, silencers, closed doors and walls
- avoid noisy work during evenings and weekends
- switch off your entire plant, or specific vehicles, ventilation units and equipment, when they’re not in use
Read the noise assessment and control guide for detailed guidance on how to manage noise and vibration.
If you receive complaints, you must monitor noise levels at different locations on your site and at different times to identify the activity that is causing the problem. Stop that activity until you’ve developed measures to reduce the noise.
Tell the Environment Agency and your neighbours about any temporary work or alterations to your site that could cause significant noise, and don’t carry out such work on weekends or evenings after 5pm.
Your site noise levels must not be significantly above background noise levels (the noise level in the area surrounding your site). If possible, your site noise level should be well below the background level.
Sometimes ambient noise on your site increases over time. This is known as ‘creeping background’. The Environment Agency may require you to take steps to reduce ambient noise from your site if this happens.
Written noise and vibration management plan
You must write a noise and vibration management plan explaining how you’ll prevent or minimise noise and vibration if your risk assessment shows that your operation will cause noise beyond your site boundary.
You can use the template noise management plan to help you decide what to include in your plan.
If you cause noise or vibration pollution but don’t already have a noise and vibration management plan, the Environment Agency may ask you to submit a plan to them.
If you have a waste, mining waste or installation permit and your activity causes pests (eg scavenging animals like birds or files) you must control them by:
- carrying out regular inspections
- securing and removing waste that attracts scavengers or flies
- employing professional pest controllers
- using deterrent methods, eg scaring
You must write a pest management plan explaining how you’ll prevent or minimise pests if your risk assessment shows that your operation is likely to cause pests.
If you don’t already have a pests management plan and your operation causes pests, the Environment Agency may ask you to submit a plan to them.
Review and update plans and procedures to control emissions
Any plans or procedures about how you prevent or minimise emissions, including odour, noise, vibration and pests, are part of your management system. You must review these if your circumstances change, for example if:
- you receive complaints
- you introduce activities that could create more emissions
- the environment you’re operating in changes, eg a school or residential development is built nearby
The Environment Agency may also agree further procedures with you if there’s a problem at your site.
Monitoring your emissions
Your permit may say what monitoring you need to do to make sure you aren’t exceeding any limits in your permit, or to check emissions from your site to make sure you’re not causing pollution, or to take action if you are.
You may need to monitor:
- pollutants within a water discharge, eg ammoniacal nitrogen in sewage discharge
- groundwater around a discharge area to check if it’s being polluted by your site
- pollutants in an air emission, eg sulphur dioxide from a chimney
You should use equipment, staff, laboratories and systems that are certified under the monitoring emissions to air, land and water (MCERTS) scheme when monitoring emissions.
Read the guidance on MCERTS certification to find equipment, processes and training schemes that are certified.
Access to monitoring points
It must be possible to access the locations you use for monitoring.
For example, it must be possible to remove manhole covers. Use lightweight manhole covers if possible. If you need to use a heavy duty cover, it must still be possible to access the monitoring point. You could:
- use a sliding manhole cover that can be easily removed
- use a heavy duty cover that has a window that you can see the monitoring location through
Keep records of the following in your management system:
- the methods you use to carry out checks
- the equipment you use in your checks and how it’s calibrated
- any maintenance required to enable your checks
- the frequency of your checks
If you operate a groundwater activity (an activity which includes a discharge to the ground or groundwater) your permit may require you to install boreholes to monitor the underlying groundwater for emissions from you site.
You’ll need to employ a consultant to tell you how to design and construct groundwater monitoring boreholes that are appropriate to your site activity.
You must restore or replace any monitoring borehole that becomes blocked, stops working, or which you can’t access at the surface. You must include details of any maintenance you carry out on boreholes in your management system.