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DoWCoP FAQs - Construction Activities
Material placed beneath buildings and hard standing such as car parks and roads within the land being developed is not waste, if the material is demonstrated to be non-waste by evidence of suitability for use and the works are carried out in accordance with the requirements of the CoP. Where there is any dispute regarding the use of material in this way then readers are referred to the Environment Agency guidance “Defining Waste Recovery: Permanent Deposit of Waste on Land”.
Where excavated material is not suitable for the proposed use it will be waste and hence the CoP will not be applicable. For example if the material has to be placed in an engineered cell and managed to prevent harm to human health or pollution of the environment then this would be viewed as having been discarded as waste. This will be a landfill and require an environmental permit. There is a distinction between this scenario and that relating to cover layers above.
The need to distinguish between “contaminated” and “uncontaminated” soils is no longer considered necessary. These are self-defining terms on a site specific basis having regard to the risk assessment, e.g. some soil may not be considered contaminated for a given land use, but would be for a more sensitive land use, on the same site.
No it is not likely to be waste. Typical uses of recovered aggregate include pipe bedding and selected backfill to sewer excavations; carriageway sub-base construction; and the construction of vertical, granular filled drains to aid consolidation of compressible clays.
Bentonite slurry cut-off walls: Bentonite / cement slurries are used to construct vertical barriers in the ground to prevent groundwater movement or to contain contaminants. Depending upon the site-specific circumstances, this would either not require an Environmental permit or may comply with the EA Enforcement Prosecution Policy Functional Guidelines. Reference should be made to the EA Remediation Position Statement Guidance for details.
Construction activities carried out on uncontaminated soils solely for the purpose of improving geotechnical properties are not generally regarded as waste treatment operations and do not require a permit. These include:
- Lime/Cement Stabilisation: Stabilisation of soils with high moisture content to improve their compaction characteristics by mixing with lime cement or cement only. If the lime is considered to be a waste material, or if the treatment is required specifically to recover a discarded material this may need to be reconsidered.
- Vibro Compaction: Vibratory techniques to improve the bearing capacity of weak soils (often made ground). These techniques use a vibratory poker that is lowered into the ground under its own weight. In most cases, stone is introduced into the ground either down the centre of the poker or into the hole when the poker is removed. The poker applies further compactive effort until adequate resistance is achieved. The combined effects of the vibration and the introduction of the stone result in an increase in the density of the soil and a consequent improvement in bearing capacity. This activity must be carried out in accordance with requirements of the EA published guidance "Piling and Penetrative Ground Improvement Methods on Land Affected by contamination: Guidance on Pollution Prevention. NC/99/73".
- Dynamic Compaction: This technique involves dropping a heavy weight from considerable height to compact weak soils (often made ground). A series of ‘footprints’ are formed which are subsequently filled with granular fill. This may either be a primary aggregate or a recycled material. Dynamic compaction is not a waste treatment activity (unless it is being done on a landfill site for example) and any risk to controlled waters must be addressed during the assessment of the Planning permission.
- Surcharging: This technique involves placing soils in a mound to compress weak soils thus reducing future settlement potential. If the material used for the surcharging is generated and then reused (in line with the CoP) on the site it should not require a WFD permit or Exemption. However, if the material is to be imported or exported from the site after use there may be requirements for waste permitting.
- Piling: There are various forms of piling which are used to transfer structural loads through weak soils to more competent materials at depth. These range from driven displacement, bored and continuous flight auger bored piles. A WFD permit will not be required for this activity. The piling activity must be carried out in accordance with requirements of the EA published guidance "Piling and Penetrative ground Improvement Methods on Land Affected by contamination: Guidance on Pollution Prevention. NC/99/73".
- Soil Reinforcement: This technique involves the introduction of geotextiles or ‘geogrids’ to layers of soil (often made ground) to improve load distribution and bearing capacity. This technique is also often applied to improve the slope stability of soils to facilitate construction of steep sided embankments. A variation, to improve the stability of cuttings, is the use of ‘soil nailing’ whereby rods are ‘fired’ into the ground at regular intervals.
- Reinforced Concrete Raft Foundations: This is a common foundation solution used on weak or potentially expansive soils. Certain ground conditions, in particular expansive clay soils require the foundation to be constructed on a bed of compacted granular material made from primary aggregate.
The dewatering of more than 20 cubic metres (20,000 litres) a day may require an Abstraction Licence under the Water Resources Act 1991.
The Water Abstraction (Transitional Provisions) Regulations 2017 removed the right to exempt dewatering from regulation controlled by the Water Resources Act. The majority of exemptions that previously applied to dewatering have been removed with effect from 1st January 2018. There are certain exemptions which are in place under the Water Abstraction and Impounding (Exemptions) Regulations 2017 in relation to construction dewatering only – including Regulation 5.
For any dewatering, whether requiring authorisation or exempt, it is recommended that you follow the guidance within Preparing a hydrogeological impact assessment.
For more information about abstraction licensing, including dewatering and other forms of abstraction, and whether a licence is required or exempt, please refer to GOV.UK: https://www.gov.uk/guidance/check-if-you-need-a-licence-to-abstract-water.
Last updated: Nov 2025