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Landfill Stewardship

The material we manage—across our recycling facilities, organics processing operations and landfills—is a function of what, and how much, people and businesses throw away. Over the years, we have observed significant changes in MSW streams. In spite of this reduction, large volumes of material that could be recycled or composted are still being sent to landfills.

As North America’s leading environmental services provider, WM is committed to ensuring that all discarded material is handled in the most environmentally beneficial way, which often includes changing the behavior of industries and individuals. We are making progress by working across our supply chain to help develop new technologies and markets for post-consumer materials while educating consumers on how to dispose of all forms of waste.

Given currently available technology, many waste streams still cannot successfully or profitably be processed into new materials. To ensure that these forms of waste do not enter natural land areas or waterways, where they can cause harm as they degrade, we manage them safely and sustainably through our network of active MSW landfill sites across the U.S. and Canada. Combined, these sites process over 100 million tons of waste annually.

WM provides solid waste collection services to millions of customers in North America—from households to public venues to large companies. After recycling or diverting various materials for reuse, we safely managed the disposal of over 100 million tons of waste each year, including common municipal trash and highly specialized materials such as medical and industrial waste. We are able to handle this volume by operating the largest network of landfills in our industry while working hard to minimize the impact those facilities have on neighbors and the environment.

Modern landfills are the products of sophisticated engineering, contributing to environmental safety and sustainability. Beyond being safe places to store waste, they are often sources of renewable energy and frequently serve new purposes after closure. WM’s modern landfills in the United States were developed under the federal RCRA, which requires rigorous siting evaluation, site characterization and scientific engineering design, as well as a comprehensive permitting and regulatory approval process that includes public notification and comment. RCRA standards also require a range of measures to prevent environmental contamination, including the use of engineered liners and covers, collection and control systems for landfill gas, and collection and treatment systems for leachate (water that accumulates in and filters through waste).

Thousands of pumps, valves, blowers and flares are required for the safe management of modern landfills. Ongoing collection of data from these assets, often collected by checking meters positioned throughout landfill sites, is essential for landfills’ safe operation.

A new system known as Connected Landfills simplifies this work, equipping landfill assets with internet-connected devices and sensors. Technicians are able to review data remotely via dashboards on mobile devices, allowing them to monitor changes, make decisions and even directly interact with equipment with the push of a button. With less time spent in transit, landfill employees will be able to spend more time managing landfills’ productivity and health. Based on its success, we plan to expand our use of this technology to other sites.

Our modern sites are designed and operated to go beyond regulatory requirements. We continually monitor and work to improve the safety and environmental security of our disposal facilities and are committed to reporting the results of these efforts. We strive to avoid conditions that cause concern for neighbors and communities, including odors and noise, regardless of whether those conditions are covered in our regulatory obligations. We also work with waste sector experts to understand what happens within landfills after they are closed. Studies have shown that modern municipal solid waste landfills tend to improve predictably over time, steadily producing less gas and less (and cleaner) leachate. Many of our landfills are designed and managed to ensure they can be used after closure for commerce, industry or even conversion into wildlife habitat or public parks.

The following efforts are supported by innovative, peer-reviewed science from WM employees working with leading experts in their fields.

Surface and Groundwater

WM’s landfills are living laboratories used to test new technologies to help us improve how we manage stormwater and leachate, and how we design and maintain landfill cover and gas collection systems. To enhance environmental performance, and reduce operational costs, we test the effectiveness of new technologies at select sites before broadly employing them at all sites. In addition, WM utilizes extensive engineering controls and practices to protect surface water and groundwater. We maintain a comprehensive network of more than 6,000 groundwater-monitoring wells around our facilities, and every landfill uses monitoring strategies—many involving sophisticated statistical evaluations—to ensure that adjacent surface water and groundwater is protected.

Our modern municipal solid waste landfill liners capture all liquids, which are then managed according to applicable regulations and design standards. Modern RCRA Subtitle C and D-regulated landfill liners continue to perform as designed, not allowing leakage through the liner and requiring cleanup of groundwater under neighboring properties. We employ hundreds of professional engineers, environmental scientists, regulatory experts and technicians to ensure that every facility works to protect surface water, stormwater and groundwater from potential operational impacts.

We use managed basins, tanks, containment structures and separators to redirect liquids for proper disposal and treatment. We also monitor on-site wastewater treatment plants to optimize efficiency and utilize a toolkit of best management practices for our field operations.

Stormwater Filtration

WM landfills collect and discharge millions of gallons of stormwater each year. The water is then managed to ensure it is clean enough to meet strict state requirements before it is released to water bodies or public treatment plants.


Innovation in Landfill Cover

A closed landfill’s final cap or cover is one of its most important environmental protection features. It must be constructed in accordance with federal and state requirements and properly maintained for years into the future. A typical final cap comprises a plastic membrane, a drainage system and a covering of soil. These covers are engineered to prevent precipitation from percolating through the landfilled waste.

WM has also permitted over 40 sites for the design and construction of innovative final covers, known as evapotranspiration covers. These covers are constructed of soil and selected vegetation and are specifically designed to store water and release it to plants through evaporation. By working with nature, evapotranspiration covers provide long-term, sustainable protection, are easy to maintain and provide a natural habitat of native plants and grasses.

Long-Term Stewardship

Just as we strive for safety and environmental quality at all our operating landfills, we want to be stewards of the environment when facilities reach their permitted capacity. WM has an independent, formally designated department, the Environmental Legacy Management Group, that manages the company’s closed landfills. The department is separate from ongoing operations, with specialists experienced in the science and engineering of site closure and long-term property management. These experts bring a fresh eye to inactive landfill sites and are attentive to opportunities for secure, long-term site maintenance, including opportunities for sites to provide new benefits to communities. Currently, WM has six closed landfills that provide areas for community parks and recreation opportunities.

  • H.O.D. Landfill, Antioch, IL
    • Softball fields
    • Field hockey fields
    • Soccer fields
    • Recreational facilities
  • Oyster Bay, Oakland, CA
    • Hiking trails
    • Picnic areas
    • Dog walking
    • Frisbee golf
  • Blackwell, Ontario, Canada
    • Walking trails
    • Dog park
    • Playground
  • Midway and Settler’s Hill contiguous sites, west metro Chicago, IL
    • Golf course
    • Cross-country course that is currently in development by the county
  • Greene Valley West, metro Chicago, IL
    • Viewing area open to the public at certain times, controlled by the Forest Preserve
  • PJP Landfill, Jersey City, NJ
    • Transferred to the City and NJDEP which allowed for use as a public park

Expertise & Research

As the largest operator of landfill networks in the industry, we provide extensive staff training to assure continuing education and dissemination of current best practices. This training includes classes in landfill design, construction and management; landfill gas systems management; and advanced instruction in air permitting and compliance. These courses are complemented by a range of eLearning modules in the management of greenhouse and other gases. Other learning opportunities enhance expertise in almost every phase of safe landfill operations.

We operate a landfill gas technician training center at the former ELDA Landfill in Cincinnati, Ohio. As recognized leaders in landfill gas management, the intent and purpose of the training center is to use internal expertise to train entry-level technicians to provide continuity and consistency across the enterprise. The training center allows for both classroom instruction on the technical aspects of landfill gas and field proficiency assessment.

We also contribute to new bodies of knowledge through research collaborations with expert stakeholders, including NASA’s Jet Propulsion Laboratory, California Air Resources Board and Carbon Mapper. WM initiated a study in 2019 to evaluate emerging measurement technologies for determining fugitive landfill methane emissions, with the goal of having a measurement system in place by 2025. Landfills currently must rely on models and other factors to estimate methane emissions. Studies comparing emission estimates from models to measurements have shown that models can overstate emissions by up to 30 times. Identifying improved methane measurement systems and technologies is key to meeting emission reduction goals.

The study is evaluating methane measurements from satellite and aerial and ground-based platforms and the assumptions to develop mass emission rates to better understand advantages and limitations of these approaches. Building on previous research by WM and academic and governmental partners, this study is comparing these approaches to tracer correlation measurements of landfill methane emissions. Our desired outcome is that these technologies will provide data sufficient to track and quantify landfill methane emissions, monitor emission reduction goals and replace or refine the current models used to estimate landfill emissions for regulatory and sustainability reporting.

Highlights of past research include a study evaluating and estimating the capacity of an evapotranspiration cover at a landfill to oxidize landfill gas emissions, which should help landfill operators and regulators agree upon the process for determining when to cease active landfill gas system controls. We also completed a case study on optimal approaches to long-term landfill management. This foundational research is key to identifying long-term stewardship options that are reliable, science-based and designed to assure safety throughout the transition of closed landfill properties to beneficial reuse after closure.

Energy reduction and GHG sustainability initiatives are deeply ingrained in our business, addressing our customers’ needs, as well as serving as an integral part of our own operations. The need to address climate change and GHG regulations is a primary driver of our customers’ goals to increase recycling and use lower-carbon fuels. Most of our current and planned capital projects will lower GHG emissions in both our own and our customers’ supply chains. As global competition for raw materials and fuel increases, sustainable solutions for managing materials will become a necessity, and, by offering sustainable, lower-carbon management options, WM is becoming competitive in new areas and insulating ourselves from long-term losses.