Local fungi, willow and municipal compost effectively remediate petroleum-contaminated soil in the Canadian North

Low energy-input alternatives based on locally available products are needed for treating petroleum-hydrocarbon spills in northern regions. We tested the efficacy of three local biological components (municipal compost, white-rot fungus: Pleurotus ostreatus and willow: Salix planifolia) to remediate diesel-contaminated soils in a subarctic climate (Whitehorse, YT, Canada), and compared their efficacy to natural attenuation and chemical fertilizers (industry standard). After the first growing season, biologically amended treatments (BAT) that contained >2 biological components, had decreased 69–73% of the diesel's F2 fraction (C10-C16), which is more than natural attenuation or fertilizer (48 and 51%). By the third growing season, the BAT dropped below the Canadian Council of Ministers of the Environment's (CCME) Agricultural & Residential/Parkland guideline (