Company: EAI
Filing Date: 2025-02-18
Form Type: 10-K
Source: 0000065984-25-000012
Chunk: 108

Company: ENTERGY ARKANSAS, LLC
Filing Date: 2025-02-18
Form: 10-K
Item: Item 1A
Chunk 108
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 the Clean Air Act if attainment is not reached in a timely manner;

•hazardous air pollutant emissions reduction programs;

•interstate air transport;

•operating permit programs and enforcement of these and other Clean Air Act programs;

•regional haze programs; and

•new and existing source standards for greenhouse gas and other air emissions.

National Ambient Air Quality Standards

The Clean Air Act requires the EPA to set National Ambient Air Quality Standards (NAAQS) for ozone, carbon monoxide, lead, nitrogen dioxide, particulate matter, and sulfur dioxide and requires periodic review of those standards.  When an area fails to meet an ambient standard, it is considered to be in nonattainment and is classified as “marginal,” “moderate,” “serious,” or “severe.”  When an area fails to meet the ambient air standard, the EPA 

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Table of ContentsPart I Item 1Entergy Corporation, Utility operating companies, and System Energy

requires state regulatory authorities to prepare state implementation plans meant to cause progress toward bringing the area into attainment with applicable standards.

Ozone Nonattainment

Entergy Texas operates two fossil-fueled generating facilities (Lewis Creek and Montgomery County Power Station) in a geographic area that is not in attainment with the applicable NAAQS for ozone.  The ozone nonattainment area that affects Entergy Texas is the Houston-Galveston-Brazoria area.  Both Lewis Creek and the Montgomery County Power Station hold all necessary permits for operation and comply with applicable air quality program regulations.  Measures enacted to return the area to ozone attainment could make these program regulations more stringent.  Entergy will continue to work with state environmental agencies on appropriate methods for assessing attainment and nonattainment with the ozone NAAQS.

Revised Fine Particulate (PM2.5) NAAQS

In March 2024 the EPA issued a final rule which revised the primary annual NAAQS for fine particulate matter, also known as PM2.5, from 12 ug/m3 to 9 ug/m3.  This new standard was effective May 2024 and initial attainment/nonattainment designations for areas with available information are due within two years, by May 2026.  For any areas designated as nonattainment for this revised standard, State Implementation Plans (SIPs) to address nonattainment requirements will be due within 18 months of the effective date of any initial nonattainment designations.  Within the areas