Annual General Conference Assemblée générale annuelle Edmonton, Alberta June 6-9, 2012 / 6 au 9 juin 2012
Landfill Runoff Treatment Options for Iqaluit Nunavut Kristi Beckman Ken Johnson AECOM Canada Ltd. Abstract: The City of Iqaluit operates a landfill system for the disposal of the solid waste generated in the community. The City holds a Water License which states that the City is required to collect, monitor and control the discharge of runoff from the site. The landfill site relies on the local permafrost regime to provide a low permeability barrier to control subsurface runoff. The City currently employs a surface water management system to divert off-site surface runoff from entering the site, and to collect on-site surface runoff for a controlled discharge into the environment. In 2006, the City upgraded the landfill’s drainage management system by constructing a perimeter berm structure, three on-site detention ponds and an off-site retention pond. The historical sampling results from the landfill runoff retention pond show that the water is consistently over the maximum allowable concentration limits for iron, manganese and zinc in the regulations applied to the landfill. The City has examined treatment options which could be applied to the landfill runoff, including wetland treatment, mechanical treatment (membrane bioreactor technology) and physical-chemical treatment with filtration. Of these four options, the physical chemical treatment with filtration is the most appropriate technology for the community because of cost, reliability and ease of operation. As a first step in applying this option, the City initiated a filtration process in 2010 to determine the practicality and the potential treatment of the runoff by filtration alone. The next phase of the trial process for the City will be applying chemical treatment in advance of the physical filtration process. 1.
Introduction
The City of Iqaluit Water License requires that the City of Iqaluit collect, monitor and control discharge of the runoff from the West 40 Landfill site. Currently the City of Iqaluit sends approximately 30,000 cubic metres of compacted waste to the landfill annually. In 2007, the calculated volume of runoff water generated from the landfill during the winter was approximately 7,700 m³ and during the summer was 6,600 m³. The West 40 Landfill currently employs a surface water management system to divert off-site surface runoff from entering the site, and to collect on-site surface runoff for a controlled discharge into the environment. The landfill site relies on the local permafrost regime to provide a low permeability barrier to control the subsurface runoff. The City has examined options for treating landfill runoff prior to discharge into the receiving environment.
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