Environmental guidance for your business in Northern Ireland & Scotland

Slurry (liquid wastes) from construction sites

Managing slurry from construction sites

What you must do

You must not dispose of liquid wastes to landfill. It can be difficult to determine whether slurry is a liquid or not.

Your waste could be defined as liquid waste if it has either of the following characteristics:

  • any waste that near instantaneously flows into an indentation void made in the surface of the waste
  • any waste (load) containing free draining liquid substance in excess of 250 litres or 10%, which ever represents the lesser amount.

Your waste haulage contractor will be able to give you disposal options in your area.

Alternatively, to find contractors in your area who can recycle or dispose of your waste material, use the NetRegs Waste Directory.

Find your nearest waste site

Any waste that contains hydrocarbons, for example hydraulic oils or diesel, will need to be disposed of as hazardous/special waste.

This can include tunnel spoil and bentonite that have been in close contact with leaking equipment. You will need to have this material laboratory tested to find out whether it is suitable to deposit in a landfill and whether the site that you intend to take the waste to is allowed to accept it.

Even if you treat waste in a screening plant, centrifuge or a similar system, it may still be subject to waste management licensing. This is dependent on a number of factors, including whether it has undergone a complete recovery operation. For each case, consult your environmental regulator for an opinion.

Contact your environmental regulator

Handling slurry

Make appropriate provision for the control and storage of slurry on site and for its disposal before you begin work.

Where the spoil from your operations is slurry or is very wet, use wagons with tailgate seals to prevent leaks onto roads. Check that all handles on the tailgate are locked in place before the wagon leaves the site. If they are not, the seal will not be effective.

Slurry from tunnelling is very difficult to treat and control. It has led to a number of serious pollution incidents and subsequent prosecutions. Plan how you are going to control, store and dispose of slurry before you begin work.

In this guideline

Bunds for oil and chemical storage on construction sites

Controlling surface water runoff from works near water

Dealing with silty water from construction sites

Dewatering excavations on a construction site

Oil Separators for construction sites

Groundwater protection when drilling or boring on a construction site

Sediment control using tanks or silt ponds on construction sites

Slurry (liquid wastes) from construction sites

Wheel washing on construction sites

Working close to water for construction sites

Construction phase SuDS

Drip trays to prevent spills on site

Working close to water for demolition businesses

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