Contaminated land clean-up using composted wastes and impacts of VOCs on land
School of the Environment and Natural Resources, Bangor University, Deiniol Road, Bangor, Gwynedd LL57 2UW Wales, United Kingdom; Department of Cell Biology and Genetics, University of Lagos, Akoka, Lagos, Nigeria
This paper describes experiments that demonstrate the effects and potential for remediation of a former steelworks site in Wales polluted with polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs). Under field conditions, PAH-contaminated soil was composted in-vessel, with or without organic feedstocks, receiving forced aeration for 80 days followed by 4 months maturation. Treatments compared PAH removal in contaminated soil to contaminated soil mixed with three different organic waste mixes after composting and after composts were spread to land. After composting, PAH concentrations declined in all treatments, by up to 38%. Sixteen months after the composts were landspread and vegetation was established, only those containing contaminated soil with organic additions exhibited further PAH removal, by up to 29%. Composting resulted in a decline in the relative concentration of small PAHs, whereas the landspreading-vegetation phase saw a decline in the relative concentration of medium PAHs in two of the three composts exhibiting PAH removal. Under controlled glasshouse conditions, vegetated soil columns of differing depths were exposed to VOCs from beneath. VOC vapour affected both shoot and root growth and soil microbial activity; effects varied with distance from the VOC source. This work demonstrated that on-site remediation of aged PAH-contaminated land can be successfully initiated by in-vessel co-composting followed by land spreading and vegetation, within a practical timeframe. © 2008 Elsevier Ltd. All rights reserved.
Co-composting; Composted wastes; Contaminated lands; Contaminated soils; Field conditions; Forced aerations; Glasshouse conditions; In vessels; Landspreading; Organic feedstocks; Organic wastes; Relative concentrations; Root growths; Site remediations; Soil columns; Soil microbial activities; Aromatic hydrocarbons; Composting; Contamination; Polycyclic aromatic hydrocarbons; Sewage; Soil pollution; Soil structure interactions; Soils; Vegetation; Volatile organic compounds; Waste treatment; Remediation; compost; contaminated land; PAH; soil pollution; volatile organic compound; waste management; Environmental Pollution; Environmental Remediation; Metallurgy; Polycyclic Hydrocarbons, Aromatic; Soil; Volatile Organic Compounds; Wales