On October 15, 2026, a division of the Colorado Court of Appeals issued its opinion in GreenLatinos v. Colorado Air Quality Control Commission, 2026 COA 74, affirming a district court judgment upholding 2023 revisions to Colorado Air Quality Control Commission (AQCC) Regulation No. 3, a rule that imposes enhanced air pollution monitoring requirements on new and modified stationary sources in disproportionately impacted communities. In a case of first impression, the court concluded that the AQCC acted reasonably and within its statutory authority under the Colorado Air Pollution Prevention and Control Act, the Environmental Justice Act (EJA) codified within it, and the state’s Administrative Procedure Act (APA).
Background
In 2021, the Colorado General Assembly enacted the EJA to “rapidly reduce pollution in disproportionately impacted communities.” Ch. 411, sec. 2(2)(b)(I), 2021 Colo. Sess. Laws 2724. Among other things, the EJA directed the AQCC to impose “enhanced modeling and monitoring requirements for new and modified sources of affected pollutants” in those communities. § 25-7-114.4(5)(b)(II)(A), C.R.S. (2026). Disproportionately impacted communities are census blocks meeting at least one of several statutory criteria tied to income, housing costs, race, linguistic isolation, tribal lands, and cumulative environmental burdens. § 24-4-109(2)(b)(II), C.R.S. (2026).
The AQCC revised Regulation 3 in 2023 to subdivide disproportionately impacted communities using EnviroScreen, a tool developed by the Colorado Department of Public Health and Environment and Colorado State University that weighs thirty-five health, social, and environmental indicators. Sources in “cumulatively impacted” communities, which score above the eightieth percentile, must implement onsite, source-specific monitoring. Sources in “socioeconomically vulnerable” communities instead pay a one-time community monitoring fee, based on emission rates, source category, and location, that funds a community monitoring program administered by the Air Pollution Control Division (the Division).
Plaintiffs GreenLatinos, 350 Colorado, and Earthworks challenged the rule’s monitoring provisions in the City and County of Denver District Court, which upheld the rule. The plaintiffs then appealed.
The Division’s Analysis
Under the APA, the central question was whether the AQCC acted reasonably. The court addressed and rejected each of the plaintiffs’ arguments in turn.
The court first considered whether the rule satisfies the EJA’s “enhanced monitoring” mandate. The plaintiffs argued that the EJA required all sources in disproportionately impacted communities to conduct source-specific monitoring. Because the EJA does not define “enhanced,” the court gave the term its ordinary meaning (to “heighten, increase” or “raise”) and concluded that the rule satisfies the statute by raising permit requirements (i.e., requiring source‑specific monitoring plans or community monitoring fees) for certain sources located within disproportionately impacted communities beyond those previously in place. It declined to infer a narrower meaning from the EJA’s broader policy goals, reasoning that the General Assembly would have said “source-specific monitoring” had it intended that result and that leaving the term undefined suggests a grant of discretion to the AQCC.
The court next rejected the plaintiffs’ contention that the community monitoring fee was unreasonable because it did not require anyone to operate community monitors and lacked record support. The rule expressly directs the Division to use collected fees to administer community monitoring, and speculation that the Division will not do so does not make the rule unreasonable. The record reflected the AQCC’s plan to install an average of five monitors per year in disproportionately impacted communities, and a direction to reevaluate fee amounts every three years. Because the fee structure rests primarily on policy considerations, the AQCC was not required to supply calculations supporting each tiered amount, so long as its reasoning was defensible.
The court then turned to the AQCC’s use of EnviroScreen to divide disproportionately impacted communities into “cumulatively impacted” and “socioeconomically vulnerable” communities. The plaintiffs argued that the AQCC offered no rationale for relying on a tool that considers more than air pollution. The court acknowledged that EnviroScreen scores reflect a range of environmental and public health factors, but it held that tailoring monitoring requirements to the overall burdens each community faces is consistent with the EJA, which directs the AQCC to impose enhanced monitoring requirements.
The court likewise upheld the eightieth percentile threshold. The plaintiffs contended that the threshold was modeled on an unrelated federal standard and excluded communities with high air pollution burdens from source-specific monitoring. The court agreed that the rule excludes some such communities, but it found the AQCC’s rationale discernible from the Statement of Basis and Purpose, which cited expert feedback, community input through the Environmental Justice Action Task Force, federal practices relevant to National Ambient Air Quality Standards, and the statutory presumption in section 24-4-109(5)(a)(I) that census block groups scoring above the eightieth percentile are disproportionately impacted.
Finally, the court held that the AQCC was not required to identify hazardous air pollutants beyond the four named in the statute. The EJA defines affected pollutants to include hazardous air pollutants “as identified by the commission, including benzene, toluene, ethylbenzene, and xylene.” § 25-7-114.4(5)(d)(I)(C). Construing that as permissive language, the court declined to read in a duty to list more hazardous air pollutants, noting that the legislature would have used mandatory language such as “shall” had it intended to impose a mandatory duty on the AQCC to list hazardous air pollutants beyond those provided in the EJA. Although the plaintiffs showed during rulemaking that twelve additional pollutants identified by EnviroScreen have health impacts, the AQCC was not obligated to adopt that alternative policy proposal.
Significance
The decision is the first appellate interpretation of the EJA’s enhanced monitoring mandate, and it confirms that the AQCC has meaningful discretion in implementing it. For permit applicants with new or modified sources in disproportionately impacted communities, the ruling leaves the current two-tier structure in place: source-specific monitoring plans in “cumulatively impacted” communities and one-time fees in “socioeconomically vulnerable” communities.
At the same time, the opinion’s reasoning and the rule’s structure itself leave room for future change. The AQCC must revisit its list of affected pollutants every three years, and the rule contemplates periodic reevaluation of the fee schedule, so the scope of monitoring obligations and fee amounts may shift through subsequent rulemakings.
The decision was authored by Judge Fox with Judges Johnson and Yun concurring.
GreenLatinos, 350 Colorado, and Earthworks collectively filed a petition for rehearing on Oct. 29.
For questions about this legal alert, please contact a member of the Davis Graham Appellate Group.