Contaminated land clean-up using composted wastes and impacts of VOCs on land.
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.
Williamson
J C
JC
School of the Environment and Natural Resources, Bangor University, Deiniol Road, Bangor, Gwynedd, LL57 2UW Wales, United Kingdom. j.c.williamson@bangor.ac.uk
Akinola
M
M
Nason
M A
MA
Tandy
S
S
Healey
J R
JR
Jones
D L
DL
D004787:Environmental Pollution / Q000517:prevention & control*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D008669:Metallurgy; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D012987:Soil / Q000032:analysis*; D055549:Volatile Organic Compounds / Q000032:analysis*; D014852:Wales
D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D055549:Volatile Organic Compounds