We will be exploring two case studies.

• The City of Toronto is currently assessing if Renewable Natural Gas projects could be implemented at two of its largest landfills: the currently operating (new) landfill, Green Lane landfill, and the closed Keele Valley Landfill. The two sites are essentially opposites in most ways: site setting, design, and age of infrastructure. Green Lane is a relatively new site, with new gas collection infrastructure being installed every year. It produces ideal gas composition, with low oxygen and other impurities. The Keele Valley landfill has been closed since 1982. It is a typical “big ole” landfill, with ageing infrastructure. The gas composition is less than ideal; higher O₂, and other impurities. The challenges and opportunities will be provided in the discussion.
  
  The site settings for the Green Lane and Keele Valley landfills are polar opposites. Green Lane is located far from the nearest city, and no gas pipelines are present within several miles of the site. Keele Valley, is located right within a busy urban city. Many years ago, it was out in the country, but the city grew to enclose it. There is little buffer, but a gas pipeline is present right at the site main entrance. So there are benefits and challenges for both sites.
  
  The assessment will include overview of the process- procurement/partnerships options, financial analysis, evaluation of gas quality, infrastructure, and the gas targets. How does a municipality make sense of this opportunity and choose the right option to meet its greenhouse gas goals?
• Landfills are significant sources of biogas. In the United States alone, there are more than 2,500 landfills, and only about 20 percent have operational waste-to-energy facilities. Most of existing facilities convert landfill gas to electricity, and the few Renewable Natural Gas (RNG) facilities that were built are at large landfills with high-capacity gas flows exceeding 3000 scfm.
  
  Small and midsize landfills offer significantly untapped potential. These sites are often not considered as candidates for RNG due to the limited gas flow they offer, and the high capital investment typically required.
  
  Some questions that will be answered during this presentation are: what is the potential for these smaller sites with gas flows between 600 – 3000 scfm? What are the environmental benefits of an RNG facility? How can an RNG project fund itself in small or medium size landfill?
  In the past three years we’ve noticed an undeniable shift in preference for RNG projects in landfills. With that in mind, we would like to raise a discussion around the parameters to consider in RNG projects in order to promote the utmost benefit for the landfill, its community, and the environment altogether.