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8748497 
Meetings & Symposia 
Phytoremediation of petroleum and salt impacted soik: A scientificaly-based innovative remediation process 
Greenberg, B; Huang, XD; Gerhardt, K; Mosley, P; Yu, XM; Liddycoat, S; Lu, X; Mccallum, B; Macneill, G; Knezevich, N; Hannaberg, M; Gerwing, P; Obal, T; Chubb, B 
2012 
420-433 
English 
We have successfully developed and implemented advanced phytoremediation systems for removal of petroleum hydrocarbons (PHC), polycyclic aromatic hydrocarbons (PAH) and salt from soils. The plant growth promoting rhizobacteria (PGPR) enhanced phytoremediation systems (PEPS) we deploy provide large amounts of root biomass in impacted soils, which promotes growth of rhizosphere microorganisms. The root and rhizosphere biomass facilitate rapid partitioning of contaminants out of the soil, and their subsequent uptake and metabolism by microbes and/or plants. PEPS result in degradation of PHC and PAH in soil and the production of large amounts of biomass for sequestration of salt into plant foliage. We have successfully performed > 25 fall-scale deployments of PEPS. PHC and salt remediation to Tier 1 criteria have been achieved at several of these sites. Not only-are these 'green' solutions effective for remediation of impacted sites, but the costs for PEPS are less than half the costs associated with landfill disposal From 2007 to 2011, we utilized PEPS at 17 sites in Alberta, British Columbia, the Northwest Territories, Manitoba, Ontario and Quebec for PHC remediation We averaged 33% remediation per year of weathered PHC from soil (mostly F3 and F4). At 7 sites, we met Tier 1 criteria, and at the remaining 10 sites, we are well on our way to achieving remediation goals. We are now performing research to optimize analytical laboratory CCME PHC quantification methods to ensure accurate measurement of soil PHC levels at phytoremediation sites. We are also using Tier 2 toxicity end-points at aresearch level to assess when the soils become non-toxic during a PEPS deployment. Our work shows that PEPS is broadly deployable at a wide variety of PHC impacted sites (including sites that have barite as a co-contaminant), with a time frame of 2 to 3 years to complete remediation. Beginning in 2009, we initiated full scale deployments of PEPS at 10 salt impacted sites in Saskatchewan, Alberta and the Northwest Territoriesi. PGPR greatly enhanced plant performance on the salt impacted soils, resulting in excellent plant growth on soils with ECe levels to 25 dS cm. Furthermore, the plants (both grasses and cereals) take up sufficient amounts of salt to make phytoremediation feasible. Notably, we have already achieved salt remediation to regulatory targets at two of the sites The innovative "green" PEPStechnologies described above are based on procedures that have been scientifically proven and are effective at full-scale field levels when deployed by qualified scientists.