title: Removing selenite from groundwater with an in situ biobarrier: laboratory studies.
abstract: Laboratory biobarriers were evaluated for their ability to remove selenite from flowing groundwater. Microbial activity in aquifers is usually limited by substrate availability, and biobarriers stimulate microbial activity by providing a substrate; for these studies soybean oil was used. Water containing 10 mg L(-1) selenite-Se was pumped through the biobarriers for 74 days and the amount present in the effluent monitored. The amounts remained high for the first 2 weeks of the study but then declined. From day 28 until the end of the study the amount of selenite-Se in the column effluents averaged 0.20 +/- 0.04 mg L(-1), a decrease of approximately 98%. At the end of the study about half of the selenite-Se applied to the columns was recovered as immobilized selenium trapped by the biobarrier. This study suggests that biobarriers containing vegetable oil might be used as a process for removing selenite from contaminated groundwater.
authors.affiliation: USDA-ARS, NRRC, 2150-D Centre Avenue, Fort Collins, CO, 80526-8119, USA. william.hunter@ars.usda.gov
authors.forename: William J
authors.initials: WJ
authors.lastname: Hunter
authors.forename: L David
authors.initials: LD
authors.lastname: Kuykendall
mesh_terms: D001673:Biodegradation, Environmental; D005374:Filtration / Q000379:methods*; D005618:Fresh Water; D009566:Nitrates / Q000378:metabolism; D016566:Organoselenium Compounds / Q000032:analysis; D012822:Silicon Dioxide; D018038:Sodium Selenite / Q000302:isolation & purification* / Q000378:metabolism; D013024:Soybean Oil / Q000378:metabolism*; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000302:isolation & purification* / Q000378:metabolism; D018508:Water Purification / Q000379:methods*
chemical_list: D009566:Nitrates; D016566:Organoselenium Compounds; D014874:Water Pollutants, Chemical; C037445:dimethyldiselenide; D012822:Silicon Dioxide; D013024:Soybean Oil; D018038:Sodium Selenite; C013503:dimethylselenide