ARCHIVE SITE - Last updated Jan. 19, 2017. Please visit for the latest NACWA information.

Member Pipeline




This case involved a challenge by NACWA to the Environmental Protection Agency's (EPA's) Sewage Sludge Incinerator (SSI) regulations. All practical legal avenues to challenge the regulations are now closed. SSI utilities should be making all efforts necessary for compliance with the SSI Rule by the March 2016 compliance deadline (or earlier in some states).

In February 2011, EPA finalized the SSI rule and the companion non-hazardous secondary materials (NHSM) rule. Both rules will have significant negative economic and operational impacts on clean water utilities that rely on SSIs for the safe and efficient management of biosolids. NACWA filed both an administrative petition for reconsideration and a legal petition for review in May 2011 to challenge EPA's final SSI rule. NACWA also filed a legal petition for review of the NHSM rule in June 2011 – that litigation has concluded (see Eco Systems Operations, et al. v. EPA). In response to these new rules, NACWA also formed a Sewage Sludge Incineration Advocacy Coalition (SSIAC) made up of NACWA member agencies and other clean water utilities that operate SSIs to support NACWA's advocacy efforts.

The main thrust of NACWA's challenge to the SSI rule at this initial stage focused on EPA's decision to regulate SSIs under Section 129 of the CAA rather than under the more flexible requirements of CAA Section 112. NACWA argued the clear language of the CAA, when read in conjunction with the Clean Water Act (CWA), directed all air emissions from publicly owned treatment works (POTWs) -- including SSI units -- to be regulated under Section 112 of the CAA in order to preserve a more flexible regulatory scheme and ensure consistency with the CWA's regulation of biosolids management.

On April 6, 2012, EPA issued its formal written denial of NACWA's request for administrative reconsideration of the Agency's SSI rule, paving the way for the Association to ramp up its legal challenge to the regulation. The denial notice outlined EPA's reasons for rejecting NACWA's request focusing primarily on procedural as opposed to substantive issues. EPA did not raise any particularly new or novel arguments in the denial. The Agency also issued a denial letter on the same day to the Sierra Club, which had petitioned for reconsideration of the rule as well. EPA published the formal denial notices in the Federal Register on April 27, 2012. Thereafter, NACWA proceeded with its legal challenge in the D.C. Circuit.

NACWA's lawsuit challenged: (1) EPA's statutory authority; and (2) EPA's technical basis for the emission standards in the final rule. In its decision, the D.C. Circuit sided with EPA on the statutory argument by ruling that the language of CAA Sections 129 and 112 was ambiguous with regard to where SSI should be regulated.

D.C. Circuit Ruling 
On August 20, 2013, the US Court of Appeals for the D.C. Circuit issued a decision icon-pdf in the case. In its decision, the court sided with EPA on the statutory argument that EPA's decision to develop a rule under Section 129 was entitled to judicial deference. The court also determined that EPA's decision to place SSIs under 129 instead of 112 was reasonable, thereby affirming EPA's decision to promulgate a 129 rule.

However, the court sided with NACWA on the majority of the Association's technical arguments and proceeded to remand a number of technical issues back to EPA for additional consideration.

The court was particularly critical of EPA's failure to sufficiently account for the variability in sewage sludge. The court agreed with NACWA's specific concern that EPA's testing for the SSI rule did not sufficiently account for the variety of conditions in which SSIs operate, including seasonal and regional variations in sludge content that can impact SSI operations. Accordingly, the court agreed that the resulting emission limits in the SSI rule cannot be valid unless EPA can provide a better justification on how it accounted for this variability. If EPA cannot provide a better justification on remand, than the emission limits must change. More broadly, the court expressed general concern with EPA's overall methodology in setting the emission limits. It directed EPA to address these concerns in a number of areas on remand with better explanations for the Agency's technical basis for the rule, or to make changes to the emissions limits if EPA cannot come up with sufficient justifications.

The fact that the court remanded the rule back to EPA on the technical issues is important to NACWA and SSIAC members for two reasons: (1) it means the court agreed with the Association that EPA's technical explanations for how it set the emission limits were not sufficient; and (2), EPA must now make changes to the rule and/or provide adequate technical explanations on remand consistent with the court's direction, and NACWA will have an additional opportunity to weigh in with EPA via comments and other advocacy efforts during that process to attempt to change the rule's emission limits. Unfortunately, the D.C. Circuit did not believe the flaws were sufficient enough to vacate the underlying rule.

The court's ruling also dismissed Sierra Club's request for more stringent SSI limits. In particular, the court agreed with EPA and NACWA that the final SSI rule did not have to contain "beyond the floor" limits to comply with the CAA. Accordingly, the court did not require the more stringent emission standards that Sierra Club requested.

On October 24, 2013, the D.C. Circuit rejected requests from the Sierra Club for rehearing of the August 20, 2013 decision icon-pdf, thereby preserving the court's partial remand of the rule to EPA to correct the significant technical flaws in the final regulations.
On May 27, 2014, NACWA filed an administrative petition icon-pdf with EPA requesting a stay and reconsideration of the Agency's SSI Rule. The petition argues that a stay and reconsideration are necessary to prevent clean water agencies from making irreversible investments while the SSI rule is on remand and to effectively address the concerns with the rule raised by the D.C. Circuit in NACWA's legal challenge. EPA has not acted on that petition.

NHSM Case History
On June 3, 2015, the D.C. Circuit Court of Appeals issued a decision icon-pdf in litigation over EPA's final NHSM Rule, dismissing challenges filed by NACWA and others to the rule. The court rejected NACWA's arguments that the "domestic sewage exclusion" (DSE) in the Resource Conservation and Recovery Act (RCRA) exempts sewage sludge from classification as a solid waste when incinerated. The court agreed with EPA's position that RCRA's definition of sludge encompasses sludge produced during the wastewater treatment process, and thus the DSE does not apply.

The NHSM Rule provides a key regulatory underpinning for EPA's SSI Rule by defining sludge when incinerated as a solid waste. NACWA challenged icon-pdf the NHSM Rule as part of the Association's overall advocacy related to SSI issues. NACWA originally filed a legal challenge to the NHSM Rule in 2011 and at the same time challenged the SSI Rule as described above. However, EPA announced in late 2011 that it would revise the NHSM Rule, and accordingly the NHSM court case was subsequently put on hold while the rule was revised. The Agency re-issued the NHSM Rule in early 2013, without addressing any of NACWA's concerns over the biosolids issue. As a result, the Association renewed its legal challenge to the rule in early May 2013, contesting EPA's decision to classify biosolids that are incinerated as a solid waste.

The rule, and the D.C. Circuit decision, only impact sewage sludge that is incinerated for disposal, not sludge managed through other methods.

With the D.C. Circuit's ruling, all practical legal avenues to challenging EPA's SSI regulations are now closed. While NACWA has been consistently advising SSI utilities to make all efforts necessary for compliance with the SSI Rule by the March 2016 compliance deadline (or earlier in some states), the decision dismissing NACWA's challenge to the underlying NHSM Rule makes it all the more important that utilities move forward as quickly as possible to comply with the SSI Rule.

See Eco Systems Operations, et al. v. EPA.

SSI Advocacy Coalition
NACWA's advocacy related to the NHSM Rule and SSI Rule has been supported by the Association's SSI Advocacy Coalition, and NACWA is grateful to members of the Coalition for their continued support.

Next Steps
While the D.C. Circuit remanded key components of the SSI rule back to EPA for further analysis, the court did NOT vacate the underlying SSI rule despite NACWA's requests to do so. Both the SSI rule and the NHSM rule, including all current compliance deadlines, remain in place while the remand process is under way.

NACWA is still engaged with EPA on a number of important regulatory issues related to the SSI Rule and will keep the membership updated on any developments, but these activities will likely have no impact on the compliance deadline.
NACWA prepared detailed Advocacy Alerts (AA 11-11 and AA 11-12) on both rules to outline for member agencies the requirements and impacts the rules will have on them.


Rulings/Pleadings (All in icon-pdf)



Legal Resource

Consent Decree e-Library key

Targeted Action Fund

Upcoming Events

Winter Conference
Next Generation Compliance …Where Affordability & Innovation Intersect
February 4 – 7, 2017
Tampa Marriott Waterside Hotel
Tampa, FL