Tyre Bales in Landfill Engineering: Drainage and Structure

Updated on: 25th February 2026 By:

Kieran Donnelly
Expert review by:

Tyre bales in landfill engineering solve problems that conventional fill materials struggle with: poor bearing capacity, chemically aggressive leachate environments, and the need for free-draining structures that perform over decades, not years. Rubber is resistant to the acids and contaminants that degrade standard drainage media, and tyre bales maintain that performance across the long service life that landfill sites demand.

This guide covers the practical applications where PAS 108-compliant bales are used within landfill sites, from leachate drainage layers and internal access roads to slope stabilisation and cap drainage. It also covers the regulatory considerations that tyre recyclers and civil engineers need to understand before supplying or specifying bales in this environment.

The Landfill Context: Why Waste Materials Make Sense Here

Landfill sites operate under strict environmental regulations and generate their own internal engineering challenges that require cost-effective, durable solutions. Leachate must be managed and collected. Access roads must be maintained across areas of poor bearing capacity. Side slopes must be stabilised and maintained over the operational life of the site and beyond. Cap structures must be drained and supported.

Tyre bales fit into landfill engineering because the material is suited to the environment. Rubber is chemically resistant to leachate, which is often acidic and contains compounds that degrade conventional fill materials over time. Tyre bales are free-draining and maintain that drainage function without the clogging problems that affect some granular drainage media in leachate environments. They are durable over the long timescales that landfill post-closure management requires. And they are low in density, which reduces load on areas of poor bearing capacity that are inherent in waste fill ground.

The use of waste-derived materials in landfill construction also appeals to the environmental regulators and operators who need to demonstrate sustainable resource management. Using tyre bales, a material that would otherwise require disposal, as a functional engineering component within a landfill structure converts a waste management problem into a construction resource.

PAS 108 compliance is required for structural applications, and understanding which landfill engineering applications require compliant bales is the starting point for tyre recyclers and civil engineers working in this sector.

Leachate Drainage Applications

Leachate management is central to the environmental performance of a landfill site. Leachate is the liquid that percolates through the waste mass, collecting contaminants as it goes. If it migrates out of the waste containment system, it represents a significant pollution risk to groundwater and surface water.

The leachate management system in a landfill typically includes a low-permeability liner at the base and sides of the waste cell, a drainage layer above the liner that collects leachate and routes it to a sump for pumping and treatment, and a monitoring system to detect any liner failure. The drainage layer is a critical component: it must have sufficient permeability to convey leachate freely to the collection point without excessive head building up above the liner.

Tyre bale drainage layers have been used in leachate management applications at landfill sites. The key properties that make them suitable are high hydraulic conductivity (water moves through a tyre bale layer far more freely than through granular drainage media), chemical resistance to leachate compounds, and long-term stability under the loads imposed by the waste mass above.

The drainage layer is typically placed as a continuous layer of bales above the geomembrane liner, with connection to the leachate collection pipes and sump. A geotextile filter layer between the waste and the bale zone prevents fine waste particles from migrating into the drainage layer and reduces its permeability over time.

For tyre recycling operations supplying bales to landfill drainage applications, the chemical environment is more demanding than surface civil engineering uses. Confirming that the bales supplied are PAS 108-compliant and understanding the leachate chemistry at the specific site is important for demonstrating fitness for purpose to the site operator and regulator.

Internal Access Roads Within Landfill Sites

Active landfill sites require internal road networks for waste delivery vehicles, compaction plants, and management vehicles to operate across the site. These roads cross areas of unconsolidated waste fill, soft clay subgrades, and disturbed ground that present challenging bearing capacity and settlement conditions for road construction.

Tyre bale road foundations within landfill sites address these conditions effectively. The same principles that apply to road construction over soft natural ground (described in more detail in the guide to PAS 108 tyre bales for road construction) apply within a landfill: the bale layer reduces vertical stress on the bearing stratum, distributes load across a greater area, and provides free drainage that prevents water pressure build-up beneath the road.

The advantage of tyre bales over conventional lightweight fill options within a landfill is that they can often be sourced directly from the landfill’s own tyre recycling operations or from a nearby recycler, reducing material supply cost and transport. Where a landfill site also handles waste tyre processing with a tyre baler on site, the bales produced can be directed to internal road construction, creating a closed loop within the site’s waste management operations.

For areas of particularly poor bearing capacity, a two-layer bale foundation with a granular capping layer above provides additional load spreading before the road pavement structure. For temporary access roads that will be decommissioned when that area of the site is restored, the bale foundation can be designed for the temporary loading period, and the bales reclaimed at restoration.

Slope Stabilisation on Landfill Side Slopes and Cap Structures

Landfill side slopes require stabilisation throughout the operational life of the site and during and after final capping. Settlement of the waste mass creates differential movement that can destabilise slope profiles and compromise drainage and capping layers. Erosion of the final soil cover is a persistent maintenance requirement on capped cells.

Tyre bale structures at the base of landfill side slopes provide a buttress that resists downslope movement and protects the toe of the slope from undercutting. Because the bale material is chemically resistant to leachate, there is no concern about degradation of the structural element even in contact with contaminated water.

On the final cap structure of a completed landfill cell, tyre bales have been used to provide drainage within the cap profile, allowing infiltrating surface water to pass freely through the cap profile to the cap drainage system while the low-permeability layer above the drainage zone prevents surface water from reaching the waste below. The same free-draining properties that make tyre bales useful as leachate drainage media make them effective as cap drainage components.

The MKII Tyre Baler produces up to 6 PAS 108-compliant bales per hour, and operations with significant bale production capability can supply the volumes needed for landfill slope and cap applications, which often require several hundred to several thousand bales per project phase.

Regulatory and Environmental Permit Considerations

Using tyre bales in landfill engineering is a regulated activity in its own right, separate from the regulation of the landfill itself. The Environment Agency (in England), SEPA (Scotland), Natural Resources Wales, and NIEA (Northern Ireland) have published guidance on the use of waste-derived materials in engineering, including tyre bales.

The key regulatory distinction is whether the tyre bales, at the point of use, are classified as waste or have achieved end-of-waste status. Under the UK’s end-of-waste criteria, waste materials that have been processed to meet a specification and are being used for a defined purpose may cease to be classified as waste. PAS 108 tyre bales may qualify for end-of-waste status in some uses, which affects how they are regulated and documented.

Landfill operators using tyre bales within their permitted site should confirm with their regulatory authority whether this use falls within the existing site permit or requires a permit modification. The answer depends on the specific permit conditions and the nature of the tyre bale application within the site.

For tyre recyclers supplying bales to landfill sites, the waste transfer documentation requirements apply in the normal way unless end-of-waste status has been confirmed for the specific supply context. Get regulatory advice specific to your supply chain before assuming any exemption applies.

Producing Bales for Landfill Engineering Supply

Operations supplying tyre bales to landfill engineering applications need PAS 108 production capability as the baseline, alongside an understanding of the specific requirements of each application.

Leachate drainage applications may require additional assurance about the chemical resistance of the bale material, which is typically addressed by reference to published research on tyre rubber behaviour in leachate environments rather than site-specific testing. Road foundation applications follow the same specification requirements as surface road construction. Slope stabilisation follows the same approach as surface slope applications.

The pre-processing line for consistent PAS 108 production starts with sorting and rim separation using the tyre rim separator, followed by sidewall cutting for truck tyres using the truck tyre sidewall cutter, and baling in the MKII Tyre Baler. The full tyre recycling equipment range from Gradeall covers every stage of this production process.

“Landfill engineering is one of the most demanding application environments for any construction material, not because the loads are the highest but because the service life is so long and the consequences of material failure are so difficult to remediate,” says Conor Murphy, Director of Gradeall International. “PAS 108 bales produced to specification and from good-quality pre-processed tyres perform well in this environment over the periods that landfill engineering requires.”

Frequently Asked Questions

Got a question about using tyre bales in landfill engineering? The answers below cover regulatory requirements, leachate resistance, documentation, and production volumes based on Gradeall’s manufacturing experience.

Are tyre bales approved for use in permitted landfill sites?

The use of tyre bales within a permitted landfill site needs to be assessed against the site’s specific permit conditions. In many cases, it falls within the permitted operations or requires a minor variation. The regulatory authority’s guidance on waste-derived materials in engineering should be consulted for each specific application. PAS 108 compliance is the specification baseline that regulators expect for structural applications.

Does leachate degrade tyre bale rubber over time?

Published research on rubber behaviour in leachate environments indicates that tyre rubber is chemically resistant to the compounds found in typical municipal solid waste leachate. Mechanical properties (density, stiffness) are maintained over extended exposure periods. Some surface degradation of exposed rubber has been observed, but this does not affect the structural performance of buried bale installations.

Can tyre bales be reclaimed from landfill applications when no longer needed?

Tyre bales in temporary applications (internal access roads, temporary slope support) can be excavated and reclaimed, though the reclaimed bales will have been in a waste environment, and their regulatory status on removal would need to be assessed. For permanent installations such as leachate drainage layers, reclamation is not typically considered part of the design.

What documentation should accompany tyre bales supplied to a landfill site?

PAS 108 production records including bale dimensions, mass, tyre input type, and production date for each batch. Waste transfer notes for the movement of the bales from the production facility to the landfill site. Any end-of-waste determination documents whether the supply is being made on an end-of-waste basis. Confirm specific documentation requirements with the landfill operator and their environmental permit holder.

How many bales are typically needed for a landfill drainage layer or access road?

Volume depends on the area to be covered and the number of bale layers. A single layer of bales at PAS 108 dimensions covers approximately 5 to 6 bales per square metre (varying by tyre type and bale dimensions). A 100-square-metre access road section with a single bale layer requires approximately 500 to 600 bales. Larger leachate drainage layers or multi-layer road foundations require proportionally more. Contact Gradeall International for production capacity information.