title: Sorption of organic compounds to fresh and field-aged activated carbons in soils and sediments.
abstract: Activated carbon (AC) amendment to polluted sediment or soil is an emerging in situ treatment technique that reduces freely dissolved porewater concentrations and subsequently reduces the ecological and human health risk of hydrophobic organic compounds (HOCs). An important question is the capacity of the amended AC after prolonged exposure in the field. To address this issue, sorption of freshly spiked and native HOCs to AC aged under natural field conditions and fresh AC amendments was compared for one soil and two sediments. After 12-32 months of field aging, all AC amendments demonstrated effectiveness for reducing pore water concentrations of both native (30-95%) and spiked (10-90%) HOCs compared to unamended sediment or soil. Values of K(AC) for field-aged AC were lower than freshly added AC for spiked HOCs up to a factor of 10, while the effect was less for native HOCs. The different behavior in sorbing native HOCs compared to freshly spiked HOCs was attributed to differences in the sorption kinetics and degree of competition for sorption sites between the contaminants and pore-clogging natural organic matter. The implications of these findings are that amended AC can still be effective in sorbing additional HOCs some years following amendment in the field. Thus, a certain level of long-term sustainability of this remediation approach is observed, but conclusions for decade-long periods cannot be drawn solely based on the present study.
authors: Norwegian Geotechnical Institute (NGI), P.O. Box 3930, Ullevål Stadium, N-0806 Oslo, Norway.
authors: Amy M P
authors: AM
authors: Oen
authors: Barbara
authors: B
authors: Beckingham
authors: Upal
authors: U
authors: Ghosh
authors: Marie Elmquist
authors: ME
authors: Kruså
authors: Richard G
authors: RG
authors: Luthy
authors: Thomas
authors: T
authors: Hartnik
authors: Thomas
authors: T
authors: Henriksen
authors: Gerard
authors: G
authors: Cornelissen
mesh_terms: D000327:Adsorption; D002244:Carbon / Q000737:chemistry*; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D009930:Organic Chemicals / Q000737:chemistry*; D045483:Rivers / Q000737:chemistry; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D009930:Organic Chemicals; D012987:Soil; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D002244:Carbon