Top: WARM provides comparisons of potential greenhouse gas emissions reductions related to different materials management methods, including landfilling. Photo courtesy of Industrious Labs and RMI.

The U.S. Environmental Protection Agency launched the Waste Reduction Model (WARM) in 1998, and it has been updated and expanded 15 times since then. It is seeking public comment through February 9, 2024 on its latest version. By way of background, WARM was created to provide comparisons of potential greenhouse gas (GHG) emissions reductions, energy savings, and economic impacts (labor hours, wages and taxes) when considering different materials management practices — source reduction, recycling, anaerobic digestion, combustion, composting and landfilling. WARM models 61 materials commonly found in municipal solid waste (MSW) and construction and demolition debris (C&D), including aluminum cans, electronics, glass, paper, plastics, food, and building materials — including new reuse factors for dimensional lumber and wood flooring. Questions EPA would like to receive input on include how well the modeled management practices represent the diversity of practices typically used in the U.S., how can WARM better align with best practices in climate change modeling and assumptions, and what can be done to enhance the clarity, transparency, relevance, and usability of WARM and its accompanying documentation. Feedback and information received will be used to inform future improvements to WARM. Access the document at this link.