Todd News
New Landfill Cell Opens
In October 2009, we opened a new landfill cell at our Knapton Quarry landfill site. Whilst all efforts are made to recycle, it has to be accepted that there is always a small residue of non recyclable wastes which are disposed into Landfill.
The new landfill cell affectionately known as Cell 2b, has a volume of approximately 200,000 m3 and took over 6 months to engineer from an area on the site where all the quarried aggregates had already been removed. Under the current PPC regulations the construction of landfill cells are to very exacting standard to ensure the full containment of wastes for up to 200 years.
The construction of the landfill cell are made up of two distinct stages:
- Subgrade works,
- Mineral liner.
Initially the bowl of the landfill cell is created with stone and compacted to the same standard as road and motorway construction. Once the subgrade works have been completed clay is imported to site for the liner.
In the instance of Knapton the clay liner is 1.5 metres deep and made up of 5 lifts of 300mm, once the clay liner has been passed a plastic liner is welded over the clay similar to a swimming pool which enhances the containment of the cell.
Once the plastic liner has been passed and tested 3 additional layers of getotextiles and minerals are laid to protect the liner. Finally a system of pipe-work is welded into the cell to ensure that all the liquids that percolate through the landfill are drained to a central point whereby they can be pumped from the landfill cell to prevent the build up of liquids. Of every tonne of waste that we handle, only approx 100kg is not recyclable and as such is disposed of into the landfill, the other 900kg is recycled.
If you have any questions about the operation of landfill sites, the standards to which they are operated or why they are required, just let us know.