4 The record articles

LMAPCD is Proposing to Change Several Air Regulations

Posted: February 8th, 2023

Authors: Patricia B. 

Update (3/1/2023): The Public Comment Period has been extended to March 15, 2023.

Louisville Metro Air Pollution Control District (District) is proposing amendments to the following District regulations:

02 – Definitions,  11 – Control of Open Burning,  13 – Control of Objectionable Odors in the Ambient Air, 15 – Version of Federal Regulations Adopted and Incorporated by Reference

These proposed amendments are currently in the public comment period which began November 16, 2022 and runs through February 16, 2023. Pending adverse comments from the public that the District must address, the proposed amendments will likely go into effect in March 2023.

The following sections summarize the proposed amendments for each regulation and the potential impacts to regulated facilities.

Regulation 1.13 – Control of Objectionable Odors in the Ambient Air

This regulation provides standards for objectionable odors which are defined as “any odor present in the ambient air that, by itself or in combination with other odors, gases, or vapors, is offensive, foul, unpleasant, or repulsive.” This proposed amendment adds qualifying language to the Section 2.1 standard prohibiting emissions of “objectionable odor.” With this amendment, the odor must cause substantial injury, detriment, nuisance, or annoyance to any considerable number of persons or to the public. (underlined words represent new added language for the proposed amendment).

This regulation is being amended in response to a lawsuit regarding alleged violations of this regulation. The added language is proposed to match state regulations regarding odors, contained in Kentucky Revised Statutes (KRS) §77.155, and to reflect the District’s current practice and policy of enforcing this regulation. The added language provides more stringent criteria on what is deemed as an objectionable odor (as determined by District investigation); however, the term “objectionable odor” remains subjective and is not determined using a prescribed field olfactometry procedure via Odor Intensity Referencing Scales (OIRS) and/or calibrated field olfactometers (e.g., a Nasal Ranger). Furthermore, the District retains sole deference to enforce the criteria because no objective criteria is established in the regulation.

Regulation 1.13 regulates objectionable odors in all of Jefferson County, Kentucky. However, District reports indicate odor complaints and investigations are most concentrated in Louisville’s Butchertown and Rubbertown neighborhoods located in the city’s central and west areas, respectively. It is important to note, enforcement actions on Regulation 1.13 (i.e., District investigations, public complaints, etc.) are likely to be highlighted in public notices associated with proposed preconstruction and operating permits which could heighten environmental justice[1] scrutiny from the District or members of the public. Enforcement actions by the District related to alleged violations of Regulation 1.13 could result in District-required implementation of odor abatement or controls, including installation of a catalytic incinerator or scrubber, tightly closing buildings with odorous materials, or updating handling procedures to minimize spillage of odor-producing materials.

If your facility has a history of enforcement actions on Regulation 1.13, ALL4 recommends reviewing odor mitigation practices whenever a facility modification or project is considered. A proactive approach to address potential sources of objectionable odors may reduce environmental justice scrutiny and demonstrate compliance with Regulation 1.13.

Regulation 1.02 – Definitions

This regulation provides definitions for the terms used throughout Parts 1-7 of the District’s Regulations. The proposed amendment to this regulation adds Appendix B containing a list of “trivial activities” and updates the definition of “Volatile organic compound” by adding one additional excluded compound primarily used in the production of polyurethane rigid insulating foams [cis-1,1,1,4,4,4-hexafluorobut-2-ene (HFO-1336mzz-Z)].

Per the District’s Preliminary Regulatory Impact Assessment (PRIA), the list of trivial activities is being incorporated into Regulation 1.02 at the request of U.S. Environmental Protection Agency (U.S. EPA) for approval in a future State Implementation Plan (SIP) submittal. Previously, the District published the list of trivial activities on its website pursuant to Section 1.41 of Regulation 2.16 (Title V Operating Permits). Trivial activities are activities that are considered inconsequential by the District and not subject to stationary source air permitting requirements.

ALL4 recommends the trivial activities list be reviewed whenever a facility modification or project is considered to determine if the change (or a portion thereof) is exempt from permitting requirements by virtue of classification as a trivial activity.

Regulation 1.11 – Control of Open Burning

This regulation provides requirements for the control of open burning by any person; in particular, this regulation describes acceptable open fires as determined by the District. The proposed amendment adds clarifying language for controlled burns performed pursuant to Section 2.1.4. At the request of prescribed fire practitioners, the District eliminated the ban on the use of accelerants for controlled burns. This amendment is not expected to materially impact permitted stationary sources.

Regulation 1.15 – Federal Regulations Adopted and Incorporated by Reference

This regulation identifies the version of U.S. EPA regulations in Title 40 to the Code of Federal Regulations (CFR) adopted and incorporated by reference in Part 5 and Part 7 of the District Regulations. The proposed amendment incorporates the most recent version of the CFR incorporated by reference elsewhere in District Regulations. This amendment is procedural in nature to provide the District appropriate authority to enforce Federal regulations.


ALL4 will be following the public comment period for any developments (e.g., changes to proposed language). If you have questions about how the proposed amendments could affect your facility’s compliance, or what your next steps should be once the changes are finalized, please reach out to me at pbarreto@all4inc.com or Stewart McCollam at smccollam@all4inc.com. ALL4 is here to answer your questions, help you evaluate how regulatory changes impact your operations, and assist your facility with all aspects of air quality compliance.


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