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This work begins with a literature-based discussion of the hazardous-waste problem represented by car tyres as hazardous waste, along with possible ways in which they might be utilised or managed. The impact of the material on the environment is characterised in the process, not least in the context of pollutants leached to the aquatic environment. Input in terms of new research results concerns the impact on water and soil of material from used car tyres being used in geotechnics. Specifically, tyre bales comprising 100–140 car vehicle tyres compressed into a lightweight block and secured by galvanised steel tie wires running around the length and depth of the bale, were researched, having been immersed in basins with alkaline and acidic water following initial preparation and pre-washing. The aim was to in some sense simulate—respectively—conditions in which rain and surface/ground water are involved, or else acid rain. To do that, the tyre bales were placed in the water for 120 days, with emerging leachate analysed after set intervals of time, with a view to changes in key physicochemical parameters of water being noted, as well as signs of the leaching of both undesirable components and priority substances, from tyres into the aqueous medium. Washing of the tyre bales was shown to induce slight pollution of water, with limited exceedance of normative values in respect of OWO content. However, this increase was not due to leaching of the Persistent Organic Pollutants tested for, but may rather have reflected contamination of tyres used, e.g., of soil at the place of previous storage. In general, waste water arising does not therefore contain substances that would stand in the way (legally) of its being discharged into a combined sewer system. Similar conclusions were arrived at through analysis of the leaching of pollutants from tyre bales exposed in the aforementioned pools of water of neutral and acidic reaction. Wastewater arising was not enriched significantly in impurities (be these metals, PAHs, phthalates, selected anions or cations), and there were therefore no exceedances of standards imposed for wastewater discharged to either waters or soil.

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The waste tyre-derived products, including whole tyres, tyre bales, shreds, chips, and crumb rubber, have begun to be used in various geotechnical applications. In particular, the use of tyre bales in the construction of a lightweight embankment on the soft ground has the potential to satisfy the demand for low-cost materials exhibiting such beneficial properties. This paper presents the comparison between the common medium sand-filled embankment and two tyre-baled structures with various granular interlayers: medium sand and rubber aggregate. To assess the efficiency of tyre bale application in soft ground conditions, two subsoils were considered in the study: sandy clay and silty clay. The stability and settlement analysis of embankments, as well as subsoil bearing capacity checking, were performed for all structural cases. Bishop’s limit equilibrium slicing method and the finite element method were used in the embankment and subsoil analysis. The comprehensive testing of tyre bales and filling materials was also carried out to obtain the set of parameters used in both analyses. The comparison allowed qualitatively assessing the effectiveness of using waste tyre bales as a filling of road embankment when founded on soft ground. The analysis revealed that the application of tyre bales generally enhanced the embankment stability, effectively reduced the embankment settlement, and reduced the normal stress in the subsoil. In the tyre-baled embankments, the slip surface is located mostly within the embankment slope, showing good rotational stability, independent of subsoil conditions.