Treatment of creosote-contaminated groundwater in a peat/sand permeable barrier--a column study.
A column study was conducted to determine if a permeable barrier can be used to treat creosote-contaminated groundwater based on sorption and biodegradation, and to determine which processes remove the various creosote compounds. Creosote-contaminated water (sterile and non-sterile) was applied to sterile and non-sterile saturated columns with peat (20 vol.%) and sand (80 vol.%) for 2 months. Temperature was 9 degrees C, inlet oxygen concentration 9-10mg/l and average residence time was two days. The peat/sand barrier material removed 94-100% polycyclic aromatic hydrocarbons (PAHs), 93-98% nitrogen/sulfur/oxygen (NSO)-containing heterocyclic aromatic compounds, and 44-97% total phenols. The peat/sand material efficiently sorbed PAHs (>2 rings) and three-ring NSO-compounds, and also sorbed significant amounts of two-ring NSO-compounds and naphthalene. Naphthalene and NSO-compounds not sorbed were biological degraded. Phenol and cresols were efficiently removed by microbial degradation. The barrier material was somewhat less efficient removing dimethylphenols (DMPs) and trimethylphenols (TMPs), where DMPs were hardly sorbed and TMPs were hardly degraded. The results imply that a peat/sand barrier can treat creosote-contaminated groundwater. Modifications might be needed for enhanced removal of DMPs and TMPs, and oxygen supply might be necessary in aquifers with low oxygen content.
Center for Soil and Environmental Research (Jordforsk), Frederik A. Dahlsvei 20, 1432 Aas, Norway. grete.rasmussen@jordforsk.no
Grete
G
Rasmussen
Gro
G
Fremmersvik
Rolf A
RA
Olsen
D000327:Adsorption; D001673:Biodegradation, Environmental; D003407:Creosote / Q000737:chemistry*; D005374:Filtration; D010539:Permeability; D012822:Silicon Dioxide; D012987:Soil; D014876:Water Pollution / Q000517:prevention & control; D018508:Water Purification / Q000379:methods*; D014881:Water Supply
D012987:Soil; D012822:Silicon Dioxide; D003407:Creosote