Many communities in America face challenges in managing solid waste. In 2018, we generated 292.4 million tons of municipal solid waste (MSW), an increase of 40% since 1990. Per capita waste generation also increased by 7% during this same period. Yet, management of MSW has changed substantially, with recycling and composting increasing from 16% in 1990 to 32.1% in 2018. Over the long-term, landfilling of waste decreased from 94% of waste generated in 1960 to 50% of the amount generated in 2018, and waste combustion has increased from 0 to 12% over the same time period.
The two primary types of disposal practices are landfilling and municipal waste combustion, or incineration. Waste transfer stations are facilities where municipal waste is unloaded from collection vehicles and re-loaded onto larger transport vehicles to be taken to a disposal site. Compliance obligations are defined primarily by state laws, within a framework of federal requirements under the Resource Conservation and Recovery Act (RCRA) and Clean Air Act (CAA).
Local governments often own and operate a solid waste landfill for final disposal and long-term containment of the majority of solid waste. The number of landfills in the U.S. has decreased by about 75% over the past 30 years, from ~7,900 in 1988 to ~1,300 in 2018. The size of the average landfill, however, has increased.
The two most common methods for depositing waste into landfills are the area fill and trench methods. In the area fill method, waste is placed in a large open section of a lined landfill and then spread and compacted in uniform layers using heaving equipment. In the trench method, which is more expensive and therefore less common, waste is placed into a trench and the material excavated to dig the trench is used as daily cover. Cover material must be applied on top of the waste mass at the end of each day as required under Subtitle D of RCRA.
Compliance under the Resource Conservation and Recovery Act (RCRA). Subtitle D of RCRA prohibits open dumps and required landfills not meeting specified minimum requirements to close. The Municipal Solid Waste Landfill Regulations (MSWLR) serve as the basis for state regulatory and permitting requirements for landfills operating on or after October 9, 1993.
The Regulations under Subtitle D of RCRA cover six aspects of landfill management
- Location criteria: suitable geological areas away from airports, floodplains, wetlands, fault areas, seismic impact zones and other unstable areas;
- Operations: requirements for cover material, disease vector and explosive gas control systems, air, access, run-on/run-off control and surface water, liquids and recordkeeping;
- Design: requirements for composite liners constructed to maintain less than a 30cm depth of leachate over the liner;
- Groundwater monitoring: requirements for systems to determine whether waste materials have escaped from the landfill and appropriate corrective measures
- Closure and post-closure care: requirements for systems to control and clean up landfill releases and achieve groundwater protection standards; and
- Financial assurance: provides funding for environmental protection during and after landfill closure.
Small landfills (receiving no more than an average of 20 tons of solid waste per day annually) may be exempt from the design, groundwater monitoring and corrective action requirements if: there is no evidence of groundwater contamination; the landfill is located in an area with less than 25 inches of precipitation annually; and the community has no other practicable solid waste disposal alternative.
Solid waste management is considered primarily local in nature: EPA sets general performance criteria; once it has approved state regulations, management and enforcement is principally a state concern.
Compliance under the Clean Air Act (CAA). As waste in landfills decomposes, it produces landfill gas, including carbon dioxide, air toxics and methane a potent greenhouse gas with a global warming potential more than 25 times that of carbon dioxide. Most landfills must report greenhouse gas emissions annually pursuant to 40 CFR 98 Subpart HH.
EPA issued updates to the New Source Performance Standards (NSPS) and Emission Guidelines (EGs) in 2016 to address and reduce methane emissions. The NSPS apply to new, modified and reconstructed MSW landfills, while the EGs apply to existing MSW landfills. Only landfills that have certain levels of waste design capacity and emissions are subject to the rules. Both rules require regulated landfills to install and operate the best available gas collection and control systems once they meet certain thresholds of landfill gas emissions. While some compliance dates were deferred in 2019, in 2021 a federal court remanded the deferral to EPA for further reconsideration. On May 10, 2021, EPA adopted final methane rules for landfills in states and Indian country where EPA-approved state plans or Tribal plans for methane are not currently in effect.
Affected landfills are also subject to the National Emission Standards for Hazardous Air Pollutants (NESHAP) (40 CFR Part 63 Subpart WWWW), which require landfill operators to develop plans to control toxic air emissions during start-up, malfunction and shutdown of the landfill; continuously monitor gas control devices; comply with reporting requirements; and take certain steps to reduce toxic air emissions from bioreactor operations. Landfills may also be regulated under prevention of significant deterioration (PSD) and non-attainment area (NAA) provisions under the CAA.
Compliance under the Clean Water Act (CWA). Landfills may also be required to obtain industrial stormwater permits under CWA regulations (see 40 CFR 122.26(b)(14)(v)), which require development of a written stormwater pollution prevention plan and implementation of control measures.
Municipal Waste Combustion.
Solid waste combustion involves the incineration of all or a portion of the solid wastestream in specially designed solid waste combustion facilities and the disposal of the residual ash in landfills. Most new incinerators have the capacity to recover and reuse the energy released during combustion (the "waste-to-energy" process). In 2017, the US combusted over 34 million tons of MSW with energy recovery.
Local governments can retrofit existing facilities, build new facilities or enter into regional partnerships. Building new facilities requires incorporating elaborate air pollution controls. Once a combustion facility is in place, the local government must ensure its proper operation, provide a relatively constant flow of waste as a feedstream and manage and dispose of the residual ash.
Compliance under CAA. 40 CFR Part 60 establishes guidelines and standards of performance for municipal waste combustors, as well as standards of performance for incinerators. The New Source Performance Standards (NSPS) for new units and Emission Guidelines (EGs) for existing units are addressed by different regulations for small (subparts AAAA and BBBB), large municipal waste combustion units (subparts Cb, Ea and Eb), and other units (subpart EEEE and FFFF). The rules require implementation of maximum achievable control technology and impose stringent emissions limits for organics, metals and acid gases. In addition, states that are home to regulated units must also either submit implementation plans under Part 62 subparts FFF and JJJ, or comply with Federal Plan requirements. Other NESHAP and NSPS requirements for major source boiler and process heaters and internal combustion engines may also apply.
Compliance under RCRA. Disposal of residual ash from the combustion of municipal waste, including fly ash and bottom ash, is regulated under RCRA and state laws. Generally, these two types of ash are combined and then disposed in either a municipal landfill or a special ash landfill. Because ash may contain toxic materials, it must be sampled and analyzed regularly to determine whether it is hazardous. Hazardous ash must be managed and disposed of as hazardous waste.
EPA publishes information and resources helpful for municipal solid waste management, implements the Subtitle D solid waste program, which includes minimum standards that are carried out primarily by state programs, and issues and updates regulations governing air and water pollution associated with municipal solid waste landfills and combustion units.
Advancing Sustainable Materials Management: Facts and Figures Fact Sheet. Resources and information on waste streams, including source reduction, recycling (including composting) and disposal.
Infographic for Municipal Solid Waste. Sources and disposition of waste streams.
NSPS and EGs for Landfills 2016 Final Rule Fact Sheet. Shows the final rules for methane management. Additional information and updates on compliance dates can be found here.
Municipal Solid Waste Landfills: National Emissions Standards for Hazardous Air Pollutants. Information on regulatory requirements applicable to emissions of these pollutants, including updates and compliance dates.
Final Amendments to Air Toxics Standards for Municipal Solid Waste Landfills Fact Sheet (2020). Recent updates to standards. Basic requirements are outlined in NESHAP for Landfills Fact Sheet (2002).
Industrial Stormwater Permit for Landfills Fact Sheet. Regulatory requirements for management stormwater runoff from these facilities.
Guidance for Sampling and Analyzing Municipal Waste Combustion Ash for Toxicity. Techniques to determine whether ash must be disposed of as hazardous waste.
Municipal Waste Combustors (MWC) - Large Units. Requirements for managing particulate matter, carbon monoxide, dioxins/furans, sulfur dioxide, nitrogen oxides, hydrogen chloride, lead, mercury and cadmium from combustors of greater than 250 tons MSW per day.
Landfill Methane Outreach Program (LMOP). Information to help waste officials reduce or avoid methane emissions from landfills. LMOP encourages the recovery and beneficial use of biogas generated from organic municipal solid waste.
Quick Reference. Short guide on Regulations Affecting Landfills and Landfill Gas Projects.
EPA Local Government Recycling Programs. Provides information on recycling programs managed at the state and local level.
Effluent Guidelines Program Plan 15. Landfills Point Source Category, focusing on PFAS discharges, is discussed in Section 6.3.3 (starting on p. 6-12). EPA's updated review of guidelines and standards regarding industrial wastewater discharges. Section 6.3.3 specifically focuses on reviewing PFAS discharges from various industrial sources.
States implement the federal criteria for operating municipal solid waste landfills and may set more stringent requirements, including permit requirements. Absent an approved state program, the federal requirements must be met by waste facilities.
State Resource Locator. Links to state solid waste agencies.
US Composting Council. A national, non-profit trade and professional organization promoting the recycling of organic materials through composting.
Solid Waste Association of North America. SWANA's mission is "to advance the practice of environmentally and economically sound management of municipal solid waste." SWANA serves over 8,100 members and thousands more industry professionals with technical conferences, certifications, publications and a large offering of technical training courses.
National Waste & Recycling Association. NWRA is a trade association representing for-profit companies in North America that provide solid, hazardous and medical waste collection, recycling and disposal services, and companies that provide professional and consulting services to the waste services industry.
Association of State and Territorial Solid Waste Management Officials (ASTSWMO). An organization supporting the environmental agencies of the states and trust territories. ASTSWMO focuses on the needs of state hazardous waste programs; non-hazardous municipal solid waste and industrial waste programs; sustainability, recycling, waste minimization and reduction programs; Superfund and state cleanup programs; waste management and cleanup activities at federal facilities; and underground storage tank and leaking underground storage tank programs.
Municipal Solid Waste in the United States (2018). Biannual report, published December 2020, containing data on MSW generation, recycling, combustion, composting and other (food waste) management; trends in MSW management; MSW material composition; environmental and economic benefits of recycling and composting; and Construction & Demolition debris management.
Reducing Contamination in Curbside Recycling Programs. SWANA report discussing the effects of contamination on curbside pick-up programs, including increasing costs and reductions in safety at material recovery facilities. Identifies the key reasons why residents place contaminants in their recycling bins in order to help local governments develop more targeted anti-contamination programs.
Solid Waste Association of North America (SWANA) Publications. Studies, guides, best practices, surveys and reports (for purchase online).
Trash Stormwater Permit Compendium. Assists Phase I and Phase II Municipal Separate Storm Sewer System (MS4) permit writers in developing trash-related provisions for MS4 permits. Includes example language, best management practices for reducing trash in stormwater and two case studies.
U.S. National Recycling Strategy. First publication in a series from EPA to support the transition to a circular economy. Identifies key actions for the municipal solid waste recycling systems, providing detailed information on improving markets for recycling commodities, increasing collection and improving materials management infrastructure, reducing contamination in material streams, enhancing related policies and programs, standardizing measurement and increasing data collection.
Model Compost Procurement Policy With Commentaries. This model policy created by Natural Resources Defense Council and the Environmental Law Institute can be used by municipalities to encourage or require the use of compost products. The policy is easily adaptable for individual municipalities. Commentary is provided explaining the benefits of key provisions and alternative approaches, as well as links to examples—all of which are intended to help guide stakeholders and policymakers in tailoring the policy to the unique circumstances of their region.
Draft National Strategy to Prevent Plastic Pollution. Provides actions local governments and others can take to eliminate land-based plastic waste.
EPAs Regulation Navigation Tool. Online resource to help owners and operators of MSW landfills determine their personalized requirements by answering successive questions about their facility.
Combustion Portal. Federal and state compliance information for combustion processes.
ReFED Insights Engine. Online data hub for food waste insights. Includes academic studies, industry papers, case studies and financial analyses for more than 40 food waste reduction solutions.
EPA Model Recycling Program Toolkit. Contains materials to help local governments, Tribes and other institutions create effective programs for recycling, composting, anaerobic digestion, reuse, repair and waste reduction. The Toolkit can help communities increase participation in recycling programs and reduce contamination in the recycling stream.
Recycling Infrastructure and Market Opportunities Map. Displays information on recycling infrastructure locations and estimated generation of waste and recycling material across the nation. The map is intended to identify infrastructure gaps, provide data for a needs analysis and increase understanding of the greatest funding needs.