Dive Brief:
- The U.S. EPA on Thursday released its final air pollution rules for new and existing municipal solid waste combustors. The updated Emissions Guidelines and New Source Performance Standards had been due since 2011 per Clean Air Act rules, but were repeatedly delayed and the subject of a nearly four-year court case brought by environmental groups.
- The rules set lower limits for nine pollutants released at the stack at 57 large facilities. In total, the limits are projected to reduce the amount of particulate matter, nitrogen oxide, sulfur dioxide, hydrogen chloride, lead, cadmium, mercury, carbon monoxide and dioxins and furans released into the atmosphere by 3,269 tons per year, according to the agency.
- The rules also add electronic reporting requirements and remove emissions reporting exemptions for startup, shutdown and malfunction of facilities, changes urged by environmental groups.
Dive Insight:
The rulemaking has been two decades in the making. The EPA last updated its air emission rules for large municipal waste combustors in 2006. Under the Clean Air Act, it’s supposed to revisit those rules every five years. Yet in 2022, a coalition of environmental groups led by East Yard Communities for Environmental Justice sued the agency for a failure to act.
The two sides reached a consent decree laying out a timeline for a final rule in 2023, and they have agreed to several deadline extensions since then. In 2024, the EPA released a draft proposal of the rules that the agency estimated would have reduced regulated pollutants by roughly 14,000 tons per year.
EPA officials met with industry representatives following the proposal, including from the Waste-to-Energy Association and Reworld, which also submitted comments expressing concerns about the available data and stringency of the proposal. The final rule is less stringent than the proposal.
The final rule explanation provides a glimpse into the current state of the waste-to-energy landscape in the United States. The updated Emissions Guidelines apply to combustion units at facilities that process greater than 250 tons of MSW per day and opened on or before Jan. 23, 2024, while updated New Source Performance Standards apply to facilities that began construction after that date.
The agency estimates that includes 152 combustion units at 57 facilities, 85% of which are mass burn combustion facilities while the rest are refuse-derived fuel facilities. Twenty-two facilities are municipally owned, while the rest are private. The agency doesn't anticipate new units coming online within the next three years.
The rules are expected to generate $90 million total in capital costs across all existing facilities, mostly for enhanced reduction of nitrogen oxide emissions. Those costs are estimated to be relatively muted per facility, totaling about 0.4% of parent companies' annual revenues on average, according to the EPA's own estimate.
The reduction in emissions levels from those facilities will be significant. As a result of the new rule, the EPA is expecting the largest reduction for nitrogen oxide emissions — roughly 2,630 tons per year. That's followed by an estimated reduction of 641 tons per year of hydrogen chloride, 40 kilograms per year of lead, two kilograms of cadmium and four grams of dioxins and furans.
Those savings would be achieved through the updated Emissions Guidelines, the EPA’s rules governing existing facilities. For most pollutants, the limits are the same across mass burn combustion and refuse-derived fuel facility types. But the limits vary by facility type for carbon monoxide and nitrogen oxide. For the latter, the EPA would achieve savings by placing more stringent limits on every facility type except for mass burn water wall facilities, the most common type operating today.
Other provisions environmental groups wanted in the final rule were not included, such as a requirement to continuously monitor particulate matter, mercury and hydrogen chloride. Instead, the final rule allows for optional continuous monitoring for those pollutants. Currently, carbon monoxide, nitrogen oxide and sulfur dioxide are the three pollutants facilities must continuously monitor, while other pollutants must be monitored by periodic stack tests.
The agency also chose to exempt certain air curtain incinerators that are burning wood from the rules. Environmental groups had opposed this proposal, arguing such activities can still produce emissions on par with burning coal or natural gas for certain pollutants.
As is typical for federal rulemakings, states now must submit updated permitting plans to the federal government one year after the new rules have gone into effect. This could mean enhanced requirements in some facilities, but not all, since some states have updated their limits beyond federal requirements in the decades since the rules were last updated.
The 152 currently operating combustion units have additional time to come into compliance with the new requirements — no more than three years after a state plan is approved and no more than five years after the EPA's guidelines are approved.
