Almost any type of solid, liquid or gaseous substance can cause water pollution. However, there are practical ways you can minimise the risk of causing a water pollution incident.

If you have a pollution prevention and control permit or waste management licence some of these measures may be included as conditions of your permit or licence, which you must comply with.

Good practice

Store and handle materials carefully

It is important that you store and handle materials in a responsible way. For example, you should:

  • store hazardous substances according to the manufacturer's instructions
  • label containers clearly and accurately
  • keep the smallest amount of materials necessary
  • store incompatible substances separately, eg chemicals that may react with each other
  • make sure you are aware of restrictions on the way you can use chemicals
  • train your staff to store and handle substances properly
  • take extra care when you handle and transport materials.

If you store oil, such as petrol or diesel, in containers there are certain legal requirements that you may need to comply with. See our guideline: Oil Storage

Prevent pollution from uncontrolled releases or leaks

Put in place measures to prevent uncontrolled releases or leaks from causing pollution. For example, you should:

  • Mark loading and unloading areas and isolate them from the surface water drainage system. If this is not possible, protect surface water drains using sandbags, mats or other devices.
  • Store all above-ground storage tanks, drums and containers on an impermeable base within a drip tray, bund or any other suitable secondary containment system to contain any spills.

GPP2: Above ground oil storage tanks (Adobe PDF)

GPP 26 Safe storage - drums and intermediate bulk containers 

  • Install drip trays, or other forms of containment, beneath any equipment that is likely to leak or result in spills of pollutants. Empty drip trays regularly so that they do not overflow. You may need to dispose of the contents of the trays as special waste.
  • Have procedures to prevent pollution from your drainage system, eg keep an updated drainage plan and colour code your drains. See the page in this guide on drainage system requirements to avoid pollution.

Be prepared for pollution incidents

Be prepared for an accident at your site. For example, you should:

  • prepare a pollution incident response plan and train staff on how to implement it
  • keep absorbent materials, such as sand and other containment equipment, suitable for containing the type and quantity of substances you store and use on your site and make sure your staff know where they are
  • make sure your site and storage areas are secure at all times, particularly outside of normal business hours, so that containers cannot be tampered with.

You may be liable for pollution that occurs as a result of damage caused by intruders.

See our guideline: Pollution incident response planning

NIEA have produced a leaflet that outlines the correct use of drains on your site. 

NIEA: Proper Use of Drains

Further information

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