title: On site remediation of a fuel spill and soil reuse in Antarctica.
abstract: The first large-scale remediation of fuel contamination in Antarctica treated 10000L of diesel dispersed in 1700t of soil, and demonstrated the efficacy of on-site bioremediation. The project progressed through initial site assessment and natural attenuation, passive groundwater management, then active remediation and the managed reuse of soil. Monitoring natural attenuation for the first 12years showed contaminant levels in surface soil remained elevated, averaging 5000mg/kg. By contrast, in five years of active remediation (excavation and biopile treatment) contaminant levels decreased by a factor of four. Chemical indicators showed hydrocarbon loss was apportioned to both biodegradation and evaporative processes. Hydrocarbon degradation rates were assessed against biopile soil temperatures, showing a phase of rapid degradation (first 100days above soil temperature threshold of 0°C) followed by slower degradation (beyond 100days above threshold). The biopiles operated successfully within constraints typical of harsh climates and remote sites, including limitations on resources, no external energy inputs and short field seasons. Non-native microorganisms (e.g. inoculations) and other organic materials (e.g. bulking agents) are prohibited in Antarctica making this cold region more challenging for remediation than the Arctic. Biopile operations included an initial fertiliser application, biannual mechanical turning of the soil and minimal leachate recirculation. The biopiles are a practical approach to remediate large quantities of contaminated soil in the Antarctic and already 370t have been reused in a building foundation. The findings presented demonstrate that bioremediation is a viable strategy for Antarctica and other cold regions. Operators can potentially use the modelled relationship between days above 0°C (threshold temperature) and the change in degradation rates to estimate how long it would take to remediate other sites using the biopile technology with similar soil and contaminant types.
authors.affiliation: Antarctic Conservation and Management, Australian Antarctic Division, Kingston, Tasmania, Australia. Electronic address: rebecca.mcwatters@aad.gov.au.
authors.forename: R S
authors.initials: RS
authors.lastname: McWatters
authors.affiliation: Antarctic Conservation and Management, Australian Antarctic Division, Kingston, Tasmania, Australia.
authors.forename: D
authors.initials: D
authors.lastname: Wilkins
authors.affiliation: Antarctic Conservation and Management, Australian Antarctic Division, Kingston, Tasmania, Australia.
authors.forename: T
authors.initials: T
authors.lastname: Spedding
authors.affiliation: Antarctic Conservation and Management, Australian Antarctic Division, Kingston, Tasmania, Australia.
authors.forename: G
authors.initials: G
authors.lastname: Hince
authors.affiliation: Antarctic Conservation and Management, Australian Antarctic Division, Kingston, Tasmania, Australia.
authors.forename: B
authors.initials: B
authors.lastname: Raymond
authors.affiliation: Antarctic Conservation and Management, Australian Antarctic Division, Kingston, Tasmania, Australia.
authors.forename: G
authors.initials: G
authors.lastname: Lagerewskij
authors.affiliation: Antarctic Conservation and Management, Australian Antarctic Division, Kingston, Tasmania, Australia.
authors.forename: D
authors.initials: D
authors.lastname: Terry
authors.affiliation: Antarctic Conservation and Management, Australian Antarctic Division, Kingston, Tasmania, Australia.
authors.forename: L
authors.initials: L
authors.lastname: Wise
authors.affiliation: Antarctic Conservation and Management, Australian Antarctic Division, Kingston, Tasmania, Australia.
authors.forename: I
authors.initials: I
authors.lastname: Snape
mesh_terms: D000864:Antarctic Regions; D001673:Biodegradation, Environmental; D052918:Environmental Restoration and Remediation; D059392:Petroleum Pollution / Q000032:analysis*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000378:metabolism*; D013696:Temperature
chemical_list: D012987:Soil; D012989:Soil Pollutants
keywords: Biopiles; Bioremediation; Cold regions; Contaminated soils; Hydrocarbons