On March 24, 2021, the Chicago City Council passed the Chicago Air Quality Ordinance, which expands the City’s ability to review and approve of zoning permits for industrial facilities that cause or contribute to air pollution. The Council’s approval of the Ordinance is seen as a political victory for Mayor Lori Lightfoot, who introduced the measure in July 2020. The Air Quality Ordinance imposes a formal review process, requires the applicant to prepare air quality and traffic studies, and expands pre-construction public comment opportunities. These new requirements will almost certainly add time, cost, and complexity to the zoning approval process.

Industries / Operations / Uses Affected

The Air Quality Ordinance requires site plan review and approval by the Chicago Department of Planning and Development (“DPD”), the Chicago Department of Public Health (“CDPH”), and the Chicago Department of Transportation (“CDOT”), for the following types of operations:

• Class III recycling

• Class IVA recycling

• Class IVB recycling

• Class V recycling

• Container storage

• Freight terminals

• Intensive manufacturing, production, and industrial services

• Outdoor storage of raw materials as a principal use

• Warehousing, wholesaling, and freight movement

• Waste-related uses

• Coke and coal bulk material uses

• Windrow composting

• Manganese-bearing material uses

All sites with the “intensive” industrial uses listed above must follow the requirements of the Air Quality Ordinance. Facilities on sites larger than 10 acres, or within 660 feet of certain residential districts, including schools or day cares, are also required to apply for Planned Development zoning districts, which sends the application through the City’s Plan Commission and City Council for approval.

Additional Environmental Studies

A key substantive requirement of the Air Quality Ordinance is that, as part of its site plan submittal, a business falling into one of the categories listed above must submit a traffic study (to be reviewed by CDOT) and an air quality impact study (to be reviewed by CDPH). However, the ordinance offers no guidance as to the level and detail of analysis that may be acceptable to the City agencies. DPD has stated that applicants will be required to use air modeling software (such as U.S. EPA’s AERMOD) “to evaluate emissions from various sources, such as processing equipment, diesel engines of yard and on-road vehicles, paved and unpaved surfaces, material handling, and wind erosion of stockpiles.” However, as noted further below, air modeling studies are extremely complex, and this brief statement does not offer comprehensive practical guidance.

Further, the ordinance does not specify what authority the City agencies have, if any, to mandate revisions to the environmental studies, to reject the studies entirely on substantive grounds, or to require mitigating measures if the studies model elevated levels of impacts. City officials have reportedly suggested that the review process may include “suggesting traffic controls to limit the routes or hours of operation for heavy trucks” serving the facility, or mitigation measures to control emissions of air pollutants, such as “increased street sweeping, installing screens around entrances, or eventually closing some sites[.]” But it is not at all clear that City officials could, pursuant to the Air Quality Ordinance as currently drafted, mandate any air quality mitigation measures over and above those that may be required under any federal or state air quality permits that a facility may need to obtain as a condition of constructing or operating the facility.

The uncertainty around the air quality modeling requirements poses particular challenges in light of the public participation requirements mandated by the Air Quality Ordinance. The Ordinance requires that prior to submitting an application for site plan review, but after submitting the air quality analysis and traffic plan for City review, the applicant must hold at least one community meeting in the City ward where the development is proposed for the purpose of explaining and soliciting public comment on the environmental studies.

But air modeling studies can be extremely challenging to explain concisely and effectively in a public forum. The challenge stems from the fact that pre-construction impact studies such as air emissions modeling are predictive and often overly conservative. Air modeling studies use computer software to estimate emissions from a facility that has not yet been constructed, and are necessarily based on a set of sophisticated assumptions about the operating conditions at and around the facility including, for example: what machinery will be operated; how many hours a week the facility will operate; how many trucks may come and go at the facility on a daily basis; and what measures may be required to mitigate air emissions, among many other factors. Often, these assumptions must be made conservatively to estimate “worst-case” or “maximum-capacity” facility operating scenarios, resulting in modeled air emissions that may be higher than what may ultimately result when the facility is constructed and operating based on real-world market demands. These nuances may not translate very well in public fora, especially if there is community opposition to the project.

In any case, these studies will impose additional costs and planning time upon the developers of facilities subject to the ordinance. Companies that are subject to the Air Quality Ordinance will want to consider engaging counsel who are well-versed in environmental law and the nuances of the City’s zoning approval process to assist them in navigating and complying with the Ordinance.