Within the UK it is estimated that around 1 million tonnes of Waste Foundry Sand (WFS) is produced, of which approximately 300k tonnes goes to re-use applications. Such applications include road embankment construction, ground improvement, concrete manufacture, flowable fills and hydraulic barriers or liners. In this study, WFSs from an iron and steel foundry were analysed for physical and chemical properties including: particle size distribution; organic matter content (OM); pH; electrical conductivity (EC); total carbon (C) and nitrogen (N) content; C: N ratio; available/soluble nutrients (mineral N, P, K and Mg); and heavy metals content to assess their suitability for manufactured soil and asphalt under the standards BS3882 and BS EN 13043 respectively. Further leachate analysis and hazardous waste analysis was carried out in accordance with the Waste Acceptance Criteria. The results showed that despite the initial fear that the heavy metals, phenolics and Poly Aromatic Hydrocarbons (PAHs) present in WFS could limit its application to soils; the limiting factor was the grain size distribution of the sand which led to the finer fraction being used in asphalt production. The total analysis of the WFS alone demonstrated very low levels of heavy metals which were within the Soil Guideline Values and within BS3882. The analytical results were used to facilitate the re-use of the WFS for both manufactured soils and asphalt. The flows of materials are illustrated and the combination of reduced economic and environmental costs provided a strong argument for the development of symbiotic relationships.
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