Description: Ecology is beginning a rulemaking that will establish a fee structure for municipal solid waste (MSW) landfills, amending two air quality rules: Chapter 173-408 WAC, Landfill Methane Emissions and Chapter 173-455 WAC, Air Quality Fee Rule. The rulemaking will add a new section to Chapter 173-408 WAC (Landfill Methane Emissions), establishing a fee structure to recover the direct and indirect costs associated with implementation of the landfill methane emissions law and rule. The fees in the new section will apply to owners or operators of municipal solid waste (MSW) landfills that are regulated under the landfill methane emissions rule and its authorizing law, Chapter 70A.540 RCW (Landfills – Methane Emissions).
This rulemaking will impact MSW landfills across the state. Ecology’s Air Quality Program (AQP) has been implementing the landfill methane emissions law and rule since June of 2024 without fee collection, using one-time funding from the legislature. MSW landfills are a significant source of methane emissions in Washington. Ecology’s most recent Greenhouse Gas Emissions Inventory reported approximately 2.5 million metric tons of carbon dioxide equivalent emissions from municipal solid waste (MSW), which is the equivalent of 583,138 gasoline-powered passenger vehicles driven for one year. Methane is a very potent greenhouse gas, with approximately 80 times the global warming potential of carbon dioxide over a 20-year period. In addition to climate impacts, there are also health impacts associated with emissions of methane and other compounds contained in landfill gas. Methane is a key precursor to the formation of ground level (tropospheric) ozone, which is classified as a criteria air pollutant by the US Environmental Protection Agency. When breathed in, ozone can irritate and inflame the respiratory tract, causing symptoms such as coughing, chest tightness, shortness of breath and wheezing, and these effects can be more serious in people with lung diseases. Landfill gas is also known to contain small percentages of hazardous air pollutants and other toxic compounds that are harmful to human health.
Establishing a fee structure through this rulemaking will enable Ecology AQP to continue implementing regulations that reduce these pollutants, such as through combustion of landfill gas, which destroys methane as well as other hazardous air pollutants contained in the gas. Chapter 173-455 WAC, Air Quality Fee Rule, consolidates most of the air quality-related fees into one rule, with exceptions listed under WAC 173-455-038. This rulemaking will amend the list of exceptions to specify that any new fees established through this rulemaking are included separately under Chapter 173-408 WAC.
Methods for providing public comment: Ecology AQP will interact with interested parties during this rulemaking following all requirements of the Washington Administrative Procedures Act, as well as Ecology’s internal processes for outreach during rulemaking. During the rule development period, scheduled from July 22, 2026, to March 2027 (tentative), we will hold at least two virtual public meetings, which will include presentations from Ecology staff on the development of the rule, as well as give interested parties the opportunity to ask questions and comment on material presented. Staff subject matter experts will be present to answer any questions to the best of their ability.
An informal public comment period will open on the day of the first public meeting and will stay open until at least seven days after the last public meeting during this rule development period. We will create a designated webpage for this rulemaking and will invite interested parties to submit comments online, in addition to opportunities to comment during public meetings or by mail. Ecology will not respond to comments during this period of rulemaking but will consider all comments submitted as we develop the rule.
Ecology AQP will also invite interested parties to submit comments during a formal public comment period, which will tentatively open in Summer of 2026. During this phase of rulemaking, we will establish another designated website to accept online comments from interested parties. Additionally, at least one virtual public hearing will be scheduled during this timeframe, in which we will accept testimony (oral comments) from the public. Ecology is required to respond to all comments submitted during this phase of rulemaking and will do so in a document called the Concise Explanatory Statement, which will be drafted in the Summer/Fall of 2027 (tentative) and published and made accessible to the public when the rule is adopted.
Ecology will also reach out to overburdened communities and vulnerable populations during this rulemaking. As this is a fee rulemaking, we intend to further examine any downstream economic impacts of fees imposed on MSW landfills and share this information during engagement for public awareness and input. Ecology AQP will translate some public outreach documents to ensure those with limited English proficiency (LEP) have access to communications on this rulemaking. At a minimum, we will send out a notice during each phase of the rulemaking process, translated into Spanish, Korean, Chinese, Vietnamese, Ukrainian and Russian, informing interested parties on rulemaking milestones and who they can contact to request an interpreter for more information. Upon request, we will also provide translation services for rulemaking documents made public, as well as interpretation services during public meetings. We will send communications out to the public through two government delivery email lists for this rulemaking: The landfill methane distribution list and the AQ rule and SIPs updates distribution list. A link to these email lists will be available on the rulemaking webpage and interested parties can subscribe to the lists to receive all updates on this rulemaking. Additionally, we will create another email list of potentially interested parties, and these parties will receive a notice when the rulemaking is announced (July 22, 2026) with information on how to receive updates and participate in this rulemaking process.
