Deposit waste over existing waste at landfills (overtipping)

You need approval from the Environment Agency before you deposit waste over completed cells that have permanently stopped taking waste.

Where you plan to deposit waste over completed cells that have permanently stopped taking waste (overtip) but have an existing permit, you must consider whether those cells were constructed to the standard required by the Landfill Directive, annex I.

Where you plan to deposit waste over completed cells that do not have an extant permit, for example at historic landfills, you must apply for a disposal or deposit for recovery permit.

Historic landfill

A historic landfill is any site that was formally used for the permanent deposit of waste. That includes where the site was not subject to regulation or where the activities at the site are not authorised by a permit.

The Environment Agency is not normally the regulator for historic landfills. They may be subject to controls under the Environmental Protection Act 1990, part 2A – contaminated land.

Your local council is the regulator for contaminated land. The Environment Agency is responsible for special sites under the contaminated land regime – check what a special site is.

Permitting

This guide applies if your proposed overtip area is on or next to:

  • cells that were constructed to the standards required by the Landfill Directive, annex 1
  • cells where the existing engineering does not meet the standards required by the Landfill Directive
  • historic landfill

If your landfill closed before or in accordance with the Landfill Directive, articles 13 and 14, your permit will not normally allow you to accept waste for disposal. You must apply to vary your permit to allow you to restart disposal operations. The Environment Agency will charge you for this.

If you do not have a permit you will need to apply for one before you can accept waste.

If you want to restore your site with waste, read restore your landfill site.

You must confirm with the planning authority that they will allow any increase in final levels or contours.

Assess the risk

You must show that the additional waste will not cause groundwater or surface water quality to deteriorate. You must take all necessary measures to prevent hazardous substances and limit non-hazardous pollutants affecting groundwater or surface water quality.

You must submit a risk assessment as part of your permit application to show that further deposits of waste will not:

  • cause or increase unacceptable discharges from the existing permitted or historic waste deposit
  • cause unacceptable discharges from the proposed waste deposit
  • prevent you monitoring the waste
  • prevent you reducing unacceptable discharges from existing and proposed waste deposits

Meet engineering standards

Where you propose to dispose of waste over completed cells, you must provide evidence in your permit application that the base and side walls to the existing waste deposit meet the standards required by the Landfill Directive, annex 1.

If you can show that the existing engineering continues to perform as intended, you will not normally need to construct engineering to Landfill Directive standards above the existing waste. You will need to remove any cap to ensure there is continuity between the new and underlying wastes.

Where you intend to dispose of waste and the existing engineering does not meet the standards required by the Landfill Directive, or the underlying waste is a historic landfill, you must separate your proposed overtip waste from the existing waste. You must separate it using an engineered structure that meets both the Landfill Directive standard and the requirements for building or extending your landfill.

Revise and maintain your management plans

Where you intend to build engineered separation above waste that is authorised by a permit but was not constructed to Landfill Directive standards, you must revise your management plans for this waste. You must describe how you will maintain leachate, landfill gas and surface water management controls during the work and after it’s completed.

You must consider:

  • changes to leachate quality over time
  • how you will manage leachate, including leachate recirculation
  • the impact of any changes to active groundwater management systems
  • how you will manage landfill gas
  • changes to slope gradients
  • differential settlement and the effects of settlement on the waste below the overtip waste
  • changes to surface water management systems
  • changes to landfill monitoring of leachate and landfill gas

You must demonstrate that your leachate collection system will operate effectively in both the underlying and proposed waste.

You must demonstrate that the engineered separation will remain effective for as long as it is required to prevent an unacceptable discharge from the proposed waste deposit.

You must be able to extend vertical infrastructure within your cell and maintain the existing control measures you have in place.

Proposed disposal over historic landfill

Where you intend to build engineered separation above a historic landfill you must consider the risks from the activity you are applying for in your permit application.

You must also consider what effect your proposed activity will have on the underlying wastes. For example:

  • could it increase gas migration or leachate generation
  • what pollution risks it will pose

You should confirm whether your local council has identified the historic landfill as contaminated land. Where they have, you may also need to satisfy them that your proposed activity will not:

  • increase the risk of significant harm to people
  • pollute groundwater or surface water