New York SIP Approval for 2010 SO2 Interstate Transport Requirements

Proposed Rule

Air Plan Approval; New York; Interstate Transport Requirements for the 2010 SO2 NAAQS

A Proposed Rule by the Environmental Protection Agency on 04/10/2026

• This document has a comment period that ends in 30 days. (05/11/2026) Submit a public comment

1 comment received. View posted comments

• PDF
• Document Details
• Document Dates

- Table of Contents

• Public Comments
• Regulations.gov Data

- Sharing

• Print
• Document Statistics
• Other Formats
• Public Inspection Published Document: 2026-06938 (91 FR 18341) Document Headings ###### Environmental Protection Agency

1. 40 CFR Part 52
2. [EPA-R02-OAR-2025-1047; FRL-13227-01-R2]

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Proposed rule.

SUMMARY:

Pursuant to the Federal Clean Air Act (CAA or the Act), the ( printed page 18342) Environmental Protection Agency (EPA) is proposing to approve the portion of the State Implementation Plan (SIP) submittal from the State of New York demonstrating that the State satisfies the interstate transport requirements, also known as the “good neighbor” provision of the CAA, for the 2010 1-hour sulfur dioxide (SO 2) primary National Ambient Air Quality Standard (NAAQS). The good neighbor provision requires that each State's implementation plan contain adequate provisions prohibiting the interstate transport of air pollution in amounts that will contribute significantly to nonattainment, or interfere with maintenance, of the NAAQS in any other State.

DATES:

Written comments must be received on or before May 11, 2026.

ADDRESSES:

Submit your comments, identified by Docket ID No. EPA-R02-OAR-2025-1047, at https://www.regulations.gov (our preferred method), or the other submission methods identified in the link below. Once submitted, comments cannot be edited or removed from the docket. EPA may publish any comment received to its public docket. Do not submit to EPA's docket at https://www.regulations.gov any information you consider to be Confidential Business Information (CBI), Proprietary Business Information (PBI), or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. EPA will generally not consider comments or comment contents located outside of the primary submission (i.e., on the web, cloud, or other file sharing system). Please visit https://www.epa.gov/​dockets/​commenting-epa-dockets for additional submission methods; the full EPA public comment policy; information about CBI, PBI, or multimedia submissions; and general guidance on making effective comments.

FOR FURTHER INFORMATION CONTACT:

Stephanie Lin, Environmental Protection Agency, Air Programs Branch, Region 2, 290 Broadway, New York, New York 10007-1866, telephone number: (212) 637-3711, email address: Lin.Stephanie@epa.gov.

SUPPLEMENTARY INFORMATION:

I. Background

A. Infrastructure SIPs

B. 2010 1-Hour SO 2 NAAQS Designations Background

II. Relevant Factors Used To Evaluate 2010 1-Hour SO 2 Interstate Transport SIPs

III. New York's SIP Submission and the EPA's Analysis

A. State Submission

B. The EPA's Evaluation Methodology

C. The EPA's Prong 1 Evaluation—Contribute Significantly to Nonattainment

D. The EPA's Prong 2 Evaluation—Interference With Maintenance

IV. The EPA's Proposed Action

V. Statutory and Executive Order Reviews

I. Background

A. Infrastructure SIPs

On June 2, 2010, the EPA established a revised primary 1-hour SO 2 NAAQS with a level of 75 parts per billion (ppb), based on a 3-year average of the annual 99th percentile of daily maximum 1-hour average concentrations. [1 ] CAA section 110(a)(1) requires all states to submit, within three years after promulgation of a new or revised NAAQS, SIP submissions to provide for the implementation, maintenance, and enforcement of the NAAQS. [2 ] The EPA has historically referred to these SIPs as “infrastructure SIPs.” Specifically, section 110(a)(1) provides the procedural and timing requirements for SIP submissions. Section 110(a)(2) lists specific elements that all states must meet related to a newly established or revised NAAQS, such as requirements for monitoring, basic program requirements, and legal authority, that are designed to assure attainment and maintenance of the NAAQS.

Section 110(a)(2)(D)(i)(I) of the CAA requires that a state's SIP include provisions prohibiting any source or other type of emissions activity in the state from emitting any air pollutant in amounts that will contribute significantly to nonattainment, or interfere with maintenance, of the NAAQS in any other State. The EPA has long interpreted this language to enact a “functional prohibition” on certain emissions from upwind states, necessitating the EPA's independent assessment whether those emissions will occur or have been adequately controlled in the state where they originate. [3 ] The EPA often refers to these requirements as Prong 1 (significant contribution to nonattainment of the NAAQS) and Prong 2 (interference with maintenance of the NAAQS). We are addressing Prongs 1 and 2 in this action. All other applicable infrastructure SIP requirements of the New York SIP submission are addressed in separate rulemakings.

B. 2010 1-Hour SO 2 NAAQS Designations Background

In this proposed action, the EPA has considered information from the 2010 1-hour SO 2 NAAQS designations process, as discussed in more detail in section III.C of this notice. For this reason, a brief summary of the EPA's designations process for the 2010 1-hour SO 2 NAAQS is included here. [4 ]

After the promulgation of a new or revised NAAQS, the EPA is required to designate areas as “nonattainment,” “attainment,” or “unclassifiable” pursuant to CAA section 107(d)(1)-(2). The process for designating areas following promulgation of a new or revised NAAQS is contained in CAA section 107(d). The EPA promulgated the 2010 1-hour SO 2 NAAQS on June 2, 2010. See 75 FR 35520 (June 22, 2010). The EPA Administrator signed the first round of designations, Round 1, for the 2010 1-hour SO 2 NAAQS on July 25, 2013. See 78 FR 47191 (August 5, 2013). [5 ] The Agency published the Data Requirements Rule (DRR) on August 21, 2015 (80 FR 51052) to provide expectations for collection of data, either monitoring or modeling, for the remaining designations. [6 ] The Federal ( printed page 18343) Register notices for Round 2 designations published on July 12, 2016 (81 FR 45039) and on December 13, 2016 (81 FR 89870). [7 ] Round 3 designations were published on January 9, 2018 (83 FR 1098) and April 5, 2018 (83 FR 14597). [8 ] Round 4 designations were published on March 26, 2021 (86 FR 16055) and April 14, 2021 (86 FR 19576). [9 ]

During the second round of designations, EPA designated Erie and Niagara counties in New York State as “unclassifiable/attainment” based on an assessment and characterization of air quality performed using air dispersion modeling software analyzing actual emissions in the area surrounding Huntley and Somerset Generating Stations, and other nearby sources which may have a potential impact in the area of analysis where maximum concentrations of SO 2 are expected. [10 ] Huntley and Somerset were identified by EPA as meeting the criteria for further analysis to determine whether there is nonattainment. [11 ] Based on information received from New York in response to the DRR, the EPA identified 11 additional sources [12 ] for which the State of New York was required to characterize air quality through modeling or monitoring or impose federally enforceable controls, bringing the total number of DRR sources for New York to 13. [13 ] For New York, the EPA designated the partial St. Lawrence County area as nonattainment during the fourth round of SO 2 designations, effective April 30, 2021, based on available monitoring data. [14 ] In Round 4, the EPA also designated the remaining areas—the remaining portion of St. Lawrence County, Cayuga County, Seneca County, and Tompkins County—as attainment/unclassifiable, completing the area designations for the 2010 1-hour SO 2 NAAQS in New York.

II. Relevant Factors Used To Evaluate 2010 1-Hour SO

                2
                 Interstate Transport SIPs

Although SO 2 is emitted from a similar universe of point and nonpoint sources as is directly emitted fine particulate matter (PM 2.5) and the precursors to ozone and PM 2.5, interstate transport of SO 2 is unlike the transport of PM 2.5 or ozone, which disperse over a wide area and can contribute to nonattainment or maintenance issues hundreds of miles from precursor-emitting sources or activities. SO 2 emissions usually do not undergo long-range transport in the atmosphere. The transport of SO 2 relative to the 2010 1-hour SO 2 NAAQS is more analogous to the transport of lead (Pb) relative to the Pb NAAQS in that emissions of SO 2 typically result in 1-hour pollutant impacts of greatest concern near the emissions source. However, ambient 1-hour concentrations of SO 2 do not decrease as quickly with distance from the source as do 3-month average concentrations of Pb, because SO 2 gas is not removed by deposition as rapidly as are Pb particles. Emitted SO 2 has wider-ranging impacts than emitted Pb, but it does not have such wide-ranging (far downwind) impacts that treatment in a manner similar to ozone or PM 2.5 would be appropriate. Accordingly, the approaches that the EPA has adopted for ozone or PM 2.5 transport are too regionally focused, and the approach for Pb transport is too tightly circumscribed to the source, to be appropriate for assessing SO 2 transport. SO 2 transport is therefore a unique case and necessitates an approach that lies between these other approaches to assessing pollutant transport.

In this proposed rulemaking, and consistent with prior SO 2 transport analyses, the EPA focused on a 50 kilometer (km)-wide zone around sources of interest because the physical properties of SO 2 result in relatively localized pollutant impacts near an emission source that drop off with distance. Given the properties of SO 2, the EPA believes that significant impacts in a downwind State are unlikely at distances greater than 50 km from a source and thus, we are focusing our review on areas within 50 km of the state lines. This scale of analysis is consistent with the “urban scale” which is the largest appropriate spatial scale for SO 2 monitors and is useful for assessing SO 2 transport and trends in area-wide air quality. [15 ]

As discussed in section III, and in further detail in the Technical Support Document (TSD) for this action, the EPA reviewed New York's SO 2 SIP submittal. We also have elected to review and assess other available information regarding SO 2 emissions and air quality for sources in New York to assist in our own evaluation. We independently analyzed such information to determine whether New York meets the interstate transport requirements described in the CAA. [16 ]

Consistent with our prior evaluations of other state's SO 2 transport obligations, we conducted a weight of evidence (WOE) analysis evaluating several sources of information, including current air quality data from monitors as well as available emissions and/or source modeling for sources in New York and in neighboring states within 50 km of the New York border. A WOE approach can be appropriate in instances, such as in this case, to determine whether or not SO 2 emissions from New York contribute to nonattainment or maintenance issues in adjoining states. A WOE analysis that is based strictly on available data may not ( printed page 18344) be sufficient in all instances for evaluating interstate SO 2 transport, and additional analysis may be necessary. Further, the term “WOE” does not establish the legal or technical meaning for what constitutes significant contribution to nonattainment or interference with maintenance for the 2010 SO 2 NAAQS. Rather, the term refers to the gathering and consideration of a wide range of information, on a case-by-case basis, to make a determination regarding whether a statutory or regulatory standard is met.

In other SO 2 transport SIP actions, the EPA has generally been able to use a WOE analysis of available information to reach a conclusion that there are no SO 2 nonattainment or maintenance issues in the relevant areas of other states, or that no sources in the upwind state are contributing to those issues. If the available evidence indicated, however, that an upwind source, sources, or emissions activities were contributing to an out-of-state SO 2 nonattainment or maintenance problem, then further analysis and a regulatory determination would be necessary concerning what amount of those emissions, if any, constituted “significant contribution” under Prong 1 or Prong 2 of the good neighbor provision.

We find that there is sufficient information to allow the EPA to make a determination that under baseline conditions and likely future emissions scenarios no New York sources are contributing or will contribute to any out-of-state SO 2 nonattainment or maintenance concerns. Therefore, it is not necessary for purposes of this action to render a determination concerning what amount of emissions would be “significant” and therefore subject to prohibition under the good neighbor provision. [17 ]

III. New York's SIP Submission and the EPA's Analysis

A. State Submission

On October 3, 2013, New York submitted to the EPA a SIP revision to address the requirements of CAA section 110(a)(1) and (2), including section 110(a)(2)(D)(i)(I) for the 2010 SO 2 NAAQS.

New York's SIP submittal stated that New York has no nonattainment areas for SO 2 within its own border, and the air quality modeling and monitoring information that was available at the time showed no violations of the NAAQS at the time of the submittal. New York also affirmed that it would continue to enforce all SIP measures and the regulation of construction of new or modified stationary sources to meet NNSR requirements and mitigate the interstate transport of SO 2.

New York's SIP submittal also stated the New York would continue to administer the CAIR program until a valid replacement for CSAPR was implemented.

The 2005 Clean Air Interstate Rule 18 covered 28 eastern states (including New York) and the District of Columbia. CAIR was designed to address interstate transport of ozone and fine particulate matter (PM 2.5) pollution. CAIR required the covered eastern states to make reductions in SO 2 and nitrogen oxides (NO X) emissions that significantly contribute to the nonattainment or interference with the maintenance of the 1997 PM 2.5 and 1997 ozone NAAQS in any downwind state (70 FR 25161, May 12, 2005). CAIR addressed interstate transport for the 1997 PM 2.5 and 1997 ozone NAAQS but did not address interstate transport for the 2010 SO 2 NAAQS. Subsequently, the D.C. Circuit invalidated CAIR and required that the rule be revised. [19 ] The court, however, left CAIR in place in order to “temporarily preserve the environmental values covered by CAIR” until the EPA could, by rulemaking, replace CAIR consistent with the court's opinion. [20 ] In 2011, the EPA promulgated the Cross-State Air Pollution Rule (CSAPR) to replace CAIR. [21 ] CSAPR addresses interstate transport for the 1997 PM 2.5, 1997 ozone and 2006 PM 2.5 NAAQS. CSAPR replaced CAIR beginning on January 1, 2015. [22 ] Neither CAIR nor CSAPR directly addresses interstate transport for the 2010 SO 2 NAAQS.

Because CAIR is no longer in place (and was only allowed to remain temporarily in place pending its replacement at the time of New York's submission, see 76 FR 48208, 48223-24 (Aug. 8, 2011)) and because it did not address the 2010 SO 2 NAAQS, New York's reliance on CAIR is not adequate on its own to demonstrate the State meets the requirements of CAA section 110(a)(2)(D)(i)(I).

In addition, both CAIR and CSAPR focused on achieving widespread reductions in PM 2.5 precursor pollutants, which include SO 2. While the programs reduced SO 2 emissions from power plants, they did so with the goal of reducing PM 2.5 levels, not with the goal of preventing contribution to nonattainment or interference with maintenance of the SO 2 standard. These programs alone cannot be relied upon to demonstrate prohibited interstate transport of SO 2 emissions were prevented. New York did not provide an analysis to show how the reductions from these programs would sufficiently address SO 2 to prevent prohibited impacts. Moreover, these rules required emissions reductions through emissions trading programs for power plants. As such, they were not designed to ensure a particular level of emissions reduction at a particular power plant and did not address SO 2 emissions at all from nonpower plant sources or emissions activities. Thus, despite these programs, individual power plant and non-power plant sources that are near State borders may be able to continue to emit at uncontrolled levels, potentially contributing to SO 2 nonattainment or maintenance issues in other States. As such, these programs alone cannot be relied upon to demonstrate prohibited interstate transport of SO 2 emissions were prevented.

While the rationale provided by New York is not an adequate basis on its own by which the EPA can determine the approvability of the State's submission, the EPA may elect to consider additional information to assist in reaching a conclusion as to whether the submission may be approved, in whole or in part, as satisfying the Act's requirements, or does not meet the Act's requirements. Here, the EPA may consider all relevant information, or generate new data and analysis, to make an independent judgment in evaluating States' compliance with the good neighbor provision, which concerns the effects of States' emissions in other States. Therefore, the EPA considered additional available information as described below and in more detail in the TSD for this action, to determine if New York's SIP complies with 110(a)(2)(D)(i)(I) requirements.

Because (1) neither CAIR nor CSAPR directly address interstate transport for ( printed page 18345) the 2010 SO 2 NAAQS (CAIR is no longer in place) and is not adequate on its own to demonstrate that the State meets the requirements of CAA section 110(a)(2)(D)(i)(I), and (2) due to the development of more detailed information concerning potential SO 2 air quality concerns in or around New York, including the partial St. Lawrence County SO 2 nonattainment area designated on March 21, 2021, the EPA is electing to consider additional information to assist in reaching a conclusion as to whether New York's submission may be approved, in whole or in part, as satisfying the Act's requirements. The EPA may consider all relevant information, or generate new data and analysis, to make an independent judgment in evaluating states' compliance with the good neighbor provision, which concerns the effects of states' emissions in other states. Therefore, the EPA considered additional available information as described below and in more detail in the TSD for this action, to reach a determination whether New York's SIP complies with 110(a)(2)(D)(i)(I) requirements.

B. The EPA's Evaluation Methodology

The EPA conducted a WOE analysis for Prong 1 and Prong 2 separately. [23 ] In its WOE analysis, the EPA evaluated all available information, including air quality data, emission sources, and modeling and emission trends in New York and the states that border or are within 50 km of New York. To identify which sources and emissions activities in New York could potentially impact downwind air quality in other states with respect to the 2010 1-hour SO 2 NAAQS, the EPA used information in the EPA's National Emissions Inventory (NEI) [24 ] and Emissions Inventory System (EIS). [25 ] The NEI is a comprehensive and detailed database of air emissions for criteria pollutants, criteria pollutant precursors, and hazardous air pollutants from air emissions sources, updated every three years using information provided by the states and other information available to the EPA. For this analysis, we largely relied on data from the 2020 NEI, because it is the most recently available, complete, and quality assured dataset. However, in evaluating emissions trends, both state-wide and at the facility level, the EPA also considered data from prior NEI reports and EIS queries, as part of the overall WOE analysis.

As shown in Table 1, the majority of SO 2 emissions in New York originate from point sources. In 2020, total SO 2 emissions from point sources in New York comprised approximately 63.79 percent of the total SO 2 emissions in the State. Non-point sources, on road and non-road emissions sources are individually much smaller and also more dispersed throughout the State and are therefore unlikely to contribute to high ambient concentrations when compared to point source contributions. Further analysis in the TSD shows that facilities with reported emissions greater than 100 tons per year (tpy) represent approximately 2.74 percent of the total number of New York SO 2 point sources but are responsible for 5,520 tons of SO 2 or 76 percent of the total New York 2020 SO 2 point source emissions. [26 ] Based on this analysis, the EPA focused our WOE analysis on SO 2 emissions from New York's larger point sources (i.e., point sources emitting over 100 tpy of SO 2) that are located within 50 km of one or more State borders.

| Category | 2020 emissions
(tpy) | Percent of total SO 2 emissions |
| --- | --- | --- |
| Point | 7,295 | 63.79 |
| Nonpoint | 3,761 | 32.89 |
| Onroad | 338 | 2.95 |
| Nonroad | 42 | 0.37 |
| SO 2 Emissions Total | 11,436 | 100 |
As described in this section, the EPA proposes that an assessment of New York's satisfaction of the Prong 1 and 2 requirements under CAA section 110(a)(2)(D)(i)(I) for the 2010 1-hour SO 2 NAAQS may be reasonably based upon several factors. These factors include evaluation of all relevant air quality modeling or monitoring information, the predicted downwind impacts projected in previous relevant modeling studies for the relevant sources and nearby areas, assessment of New York's SO 2 point source emissions of more than 100 tpy of SO 2 per facility that are located within approximately 50 km of another state, assessment of other states' point sources emitting more than 100 tpy of SO 2 located within approximately 50 km of New York, and assessment of federal regulations and SIP-approved regulations affecting New York's SO 2 sources. The EPA's evaluation is informed by all available data at the time of this rulemaking. [27 ]

The EPA notes that if this information were insufficient to draw a reasonable conclusion concerning whether New York is “significantly contributing” or not, then it would not be possible to propose approval based only on this information. In other words, in general, the absence of information concerning whether interstate transport is occurring is not in itself sufficient justification for approving a good neighbor SIP submission. For example, if there were inadequate monitoring or modeling information to characterize the effects of a large, near-border source of SO 2 emissions, it may be appropriate to conduct, or ask the state to conduct, further analysis to better characterize that source and its effects, in order to reach a determination concerning ( printed page 18346) whether the good neighbor provision is being met. See, e.g., 88 FR 41344 (June 26, 2023) (proposing approval of Tennessee SO 2 transport SIP submission based on updated modeling conducted to better characterize emissions from the Eastman Chemical facility). In this case, the information available to the EPA, as analyzed in the accompanying TSD and summarized below, is sufficient to conclude that sources in New York are not and will not emit SO 2 pollution in violation of the good neighbor provision for the 2010 SO 2 NAAQS.

C. The EPA's Prong 1 Evaluation—Contribute Significantly to Nonattainment

Prong 1 of the “good neighbor” provision requires states' plans to prohibit emissions that will contribute significantly to nonattainment of the NAAQS in another state. The EPA's evaluation [28 ] of whether New York has met its Prong 1 transport obligations was accomplished by considering all available information, including the following: SO 2 ambient air quality in New York and neighboring states; SO 2 emissions trends for New York and neighboring states; potential ambient impacts of SO 2 emissions from certain facilities [29 ] in New York on neighboring states; New York's SIP-approved regulations specific to SO 2 emissions and permit requirements; and other SIP-approved or federally enforceable regulations which may reduce SO 2 emissions either directly or indirectly.

Based on the EPA's analysis, we propose to determine that there are no SO 2 nonattainment issues in the relevant areas in other states bordering New York, and as such the EPA proposes to determine that New York's SIP satisfies the requirements of Prong 1 of CAA section 110(a)(2)(D)(i)(I). This proposed determination is based on the following considerations:

• There is one monitor recording violations of the 2010 1-hour SO 2 NAAQS located in New York. However, all monitors within 50 km of the New York border have design values (DV) [30 ] that are below the 75 ppb SO 2 NAAQS. Current DVs for New York's AQS SO 2 monitors within 50 km of another state's border have remained below the 2010 1-hour SO 2 NAAQS from 2019-2023; similarly, SO 2 monitors in neighboring states (Pennsylvania, Vermont, Connecticut, New Jersey, Massachusetts) within 50 km of New York have 2023 DVs (2021-2023) below the 2010 1-hour SO 2 NAAQS;

• Downward SO 2 emissions trends in New York and its surrounding states (Pennsylvania, Vermont, Connecticut, New Jersey, Massachusetts), when considered together with the other factors discussed as part of EPA's WOE analysis, further support that New York's sources will not significantly contribute to any other states' nonattainment of the 2010 1-hour SO 2 NAAQS;

• A source-specific analyses of every New York 100 tpy source located within 50 km of the state border indicates that the sources do not contribute to nonattainment in other states. These analyses draw upon available emissions data, monitoring data, air quality modeling, control requirements, wind rose data, and other relevant information to assess the likelihood of air quality impacts from these sources to areas in surrounding states. A detailed discussion of each source-specific analysis is contained in Section IV.B.3 of the TSD accompanying this action. Below we cover some of the principal evidence that confirms that emissions from New York do not contribute to nonattainment in other states.

• All monitors closest to the New York SO 2 Areas of Interest (Sources > 100 tpy located within 50 km of adjacent state) have consistently recorded DVs well below the standard for years 2012-2023, indicating that these facilities are not causing exceedances in New York and would not cause exceedances in Pennsylvania, Vermont, Connecticut, New Jersey and Massachusetts.

• For the St. Lawrence source—Alcoa—monitors nearby have recorded DVs above the NAAQS. However, this source being 122 km from the nearest state line (Vermont) supports a determination that emissions from these sources are not contributing to nonattainment across the border into neighboring states.

• For the remainder of the New York SO 2 Areas of Interest (Sources > 100 tpy located within 50 km of adjacent state), either wind rose data, amount of emissions in 2022, or distance between the sources and the nearest neighboring state border supported a determination that these sources will not contribute to nonattainment of the NAAQS in Massachusetts. New Jersey, Connecticut, Vermont, and Pennsylvania.

• Further there are SIP-approved and federal emissions control regulations within New York that will continue to ensure that SO 2 emissions will be effectively controlled for existing and new sources or modifications.
  Based on this evaluation, as more thoroughly discussed in our TSD for this action, the EPA proposes to find that sources within New York will not significantly contribute to nonattainment of the 2010 1-hour SO 2 NAAQS in any other state.

D. The EPA's Prong 2 Evaluation—Interference With Maintenance

Prong 2 of the “good neighbor” provision requires state plans to prohibit emissions that will interfere with maintenance of a NAAQS in another state. The EPA's evaluation of whether New York has met its Prong 2 transport obligations was accomplished by considering all available information, with a focus on current air quality data, SO 2 emissions trends for New York and neighboring states, and how existing and future sources of SO 2 are addressed through existing SIP-approved and federally enforceable regulations. This evaluation builds upon the analysis conducted for significant contribution to nonattainment (Prong 1), which evaluated SO 2 ambient air quality in New York and neighboring states and potential ambient impacts of SO 2 emissions from certain facilities in New York on neighboring states.

Based on the EPA's analysis, we propose to find that SO 2 levels in neighboring states near the New York border do not indicate an inability to maintain the SO 2 NAAQS that could be attributed in part to sources in New York, and as such the EPA proposes to determine that New York's SIP satisfies the requirements of Prong 2 of CAA section 110(a)(2)(D)(i)(I). This determination is based on the following considerations:

• Current 2021-2023 DVs for SO 2 monitors in New York within 50 km of another state's border and in neighboring states (Pennsylvania, New Jersey, Vermont, Connecticut, and Massachusetts) within 50 km of New York's border are below the standard except for one (Alcoa West), indicating that the areas in the vicinity of these monitors are all currently in attainment of the 2010 1-hour SO 2 NAAQS except for the partial St. Lawrence area;
• State-wide emissions trends in New York and surrounding states indicate generally declining SO 2 emissions and consequently ambient air concentrations in the relevant areas; ( printed page 18347)
• Current New York statutes, SIP-approved measures, and federal emissions control programs control SO 2 emissions from certain sources within New York; and
• New York's SIP-approved PSD, major New Source Review (NSR) regulations and minor source NSR permit programs address future new and modified SO 2 sources above major and minor permitting thresholds with the intent of ensuring that the SO 2 NAAQS will not be exceeded as a result of new facility construction or existing facility modification within the state or in surrounding states. Based on this evaluation, as more thoroughly discussed in our TSD for this action, the EPA proposes to find that sources within New York will not interfere with maintenance of the 2010 1-hour SO 2 NAAQS in any other state.

IV. The EPA's Proposed Action

The EPA is proposing to approve the Prong 1 and Prong 2 portions of the infrastructure SIP submission submitted by the state of New York on October 3, 2013, addressing interstate transport for the 2010 1-hour SO 2 NAAQS. Based on the EPA's WOE analysis and as more thoroughly discussed in the TSD, the EPA proposes to determine that emissions from New York will not contribute significantly to nonattainment in, or interfere with maintenance of, any other state with respect to the 2010 SO 2 NAAQS. We therefore propose to find that New York's SIP contains adequate provisions consistent with CAA section 110(a)(2)(D)(i)(I).

V. Statutory and Executive Order Reviews

Under the CAA, the Administrator is required to approve a SIP submission that complies with the provisions of the CAA and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, EPA's role is to approve state choices, provided that they meet the criteria of the CAA. Accordingly, this action merely approves state law as meeting Federal requirements and does not impose additional requirements beyond those imposed by state law. For that reason, this action:

• Is not a significant regulatory action subject to review by the Office of Management and Budget under Executive Order 12866 (58 FR 51735, October 4, 1993);
• Is not subject to Executive Order 14192 (90 FR 9065, February 6, 2025) because SIP actions are exempt from review under Executive Order 12866:
• Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
• Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.);
• Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);
• Does not have federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999);
• Is not subject to Executive Order 13045 (62 FR 19885, April 23, 1997) because it approves a state program;
• Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001); and
• Is not subject to requirements of section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application of those requirements would be inconsistent with the CAA. In addition, the SIP is not approved to apply on any Indian reservation land or in any other area where EPA or an Indian Tribe has demonstrated that a Tribe has jurisdiction. In those areas of Indian country, the rule does not have Tribal implications and will not impose substantial direct costs on Tribal governments or preempt Tribal law as specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

List of Subjects in 40 CFR Part 52

• Environmental protection
• Air pollution control
• Incorporation by reference
• Intergovernmental relations
• Sulfur dioxide
• Reporting and recordkeeping requirements Authority: 42 U.S.C. 7401 et seq.

Michael Martucci,

Regional Administrator, Region 2.

Footnotes

1.

                     
                    See [75 FR 35520](https://www.federalregister.gov/citation/75-FR-35520) (June 22, 2010).

Back to Citation 2.

                     On December 10, 2024, the EPA revised the secondary NAAQS for SO 2 to an annual average, averaged over three consecutive years, with a level of 10 parts per billion (ppb). 
                    See [89 FR 105692](https://www.federalregister.gov/citation/89-FR-105692) (December 27, 2024).

Back to Citation 3. See Genon Rema LLC v. EPA, 722 F.3d 513, 520-24 (3d Cir. 2013); Appalachian Power Co. v. EPA, 249 F.2d 1032, 1045-47 (D.C. Cir. 2001); see also 71 FR 25328, 25335 (April 28, 2006) (explaining that the SIP/FIP process under section 110 and the petitioning process for direct federal regulation under section 126 provide independent means of effectuating the same “functional prohibition” found in CAA section 110(a)(2)(D)(i)(I)).

Back to Citation 4.

                     While designations may provide useful information for purposes of analyzing transport, the EPA notes that designations themselves are not dispositive of whether or not upwind emissions are impacting areas in downwind states. The EPA has consistently taken the position that CAA section 110(a)(2)(D)(i)(I) requires elimination of significant contribution and interference with maintenance in other states, and this analysis is not limited to designated nonattainment areas. Nor must designations for nonattainment areas have first occurred before states or the EPA can act under section 110(a)(2)(D)(i)(I). *See, e.g.,* Clean Air Interstate Rule, [70 FR 25162](https://www.federalregister.gov/citation/70-FR-25162), [25265](https://www.federalregister.gov/citation/70-FR-25265) (May 12, 2005); Cross State Air Pollution Rule, [76 FR 48208](https://www.federalregister.gov/citation/76-FR-48208), [48211](https://www.federalregister.gov/citation/76-FR-48211) (Aug. 8, 2011); Final Response to Petition from New Jersey Regarding SO 2 Emissions From the Portland Generating Station, [76 FR 69052](https://www.federalregister.gov/citation/76-FR-69052) (Nov. 7, 2011) (finding facility in violation of the prohibitions of CAA section 110(a)(2)(D)(i)(I) with respect to the 2010 1-hour SO 2 NAAQS prior to issuance of designations for that standard).

Back to Citation 5.

                     EPA and state documents and public comments related to the Round 1 final designations are in the docket at *regulations.gov* with Docket ID No. EPA-HQ-OAR-2012-0233 and at EPA's website for SO 2 designations at *[https://www.epa.gov/​sulfur-dioxide-designations](https://www.epa.gov/sulfur-dioxide-designations).*

Back to Citation 6.

                     The DRR requires state air agencies to characterize air quality, through air dispersion modeling or monitoring, in areas associated with 

                    sources that emitted in 2014 2,000 tons per year (tpy) or more of SO 2, or that have otherwise been listed under the DRR by EPA or state air agencies. In lieu of modeling or monitoring, state air agencies, by specified dates, could elect to impose federally enforceable emissions limitations on those sources restricting their annual SO 2 emissions to less than 2,000 tpy, or provide documentation that the sources have been shut down. EPA used the information generated by implementation of the DRR to help inform Round 4 designations for the 2010 1-hour SO 2 NAAQS.

Back to Citation 7.

                     EPA and state documents and public comments related to the Round 2 final designations are in the docket at regulations.gov with Docket ID No. EPA-HQ-OAR-2014-0464 and at EPA's website for SO 2 designations at *[https://www.epa.gov/​sulfur-dioxide-designations](https://www.epa.gov/sulfur-dioxide-designations).*

Back to Citation 8.

                     EPA and state documents and public comments related to Round 3 final designations are in the docket at *regulations.gov* with Docket ID No. EPA-HQ-OAR-2017-0003 and at EPA's website for SO 2 designations at *[https://www.epa.gov/​sulfur-dioxide-designations](https://www.epa.gov/sulfur-dioxide-designations).*

Back to Citation 9.

                     EPA and state documents and public comments related to Round 4 final designations are in the docket at *regulations.gov* with Docket ID No. EPA-HQ-OAR-2020-0037 and at EPA's website for SO 2 designations at *[https://www.epa.gov/​sulfur-dioxide-designations](https://www.epa.gov/sulfur-dioxide-designations).* The Round 4 2010 1-hour SO 2 NAAQS designations action was signed by former EPA Administrator Andrew Wheeler on December 21, 2020, pursuant to a court-ordered deadline of December 31, 2020. For administrative purposes only, and in compliance with requirements of the Office of the Federal Register, former Acting Administrator Jane Nishida re-signed the same action on March 10, 2021, for publication in the **Federal Register**.

Back to Citation 10. 81 FR 45039 (July 12, 2016); https://www.epa.gov/​sites/​default/​files/​2016-03/​documents/​ny-rec-r2.pdf.

Back to Citation 11. https://www.epa.gov/​sites/​default/​files/​2016-03/​documents/​ny-epa-tsd-r2.pdf.

Back to Citation 12. https://www.epa.gov/​sites/​default/​files/​2016-06/​documents/​ny-response.pdf.

Back to Citation 13. https://www.epa.gov/​sites/​default/​files/​2016-06/​documents/​drr-source-list-epa.pdf.

Back to Citation 14. https://www.epa.gov/​sites/​default/​files/​2020-12/​documents/​06-ny-rd4​final​so2​designations​tsd.pdf; see 86 FR 16055 (March 19, 2021).

Back to Citation 15.

                     For the definition of spatial scales for SO 2, see [40 CFR part 58, Appendix D](https://www.ecfr.gov/current/title-40/part-58/appendix-Appendix%2520D%2520to%2520Part%252058), section 4.4 (“Sulfur Dioxide (SO 2) Design Criteria”). For further discussion on how the EPA applies these definitions with respect to interstate transport of SO 2, see the EPA's proposed rulemaking on Connecticut's SO 2 transport SIP. 
                    See [82 FR 21351](https://www.federalregister.gov/citation/82-FR-21351), [21352](https://www.federalregister.gov/citation/82-FR-21352), [21354](https://www.federalregister.gov/citation/82-FR-21354) (May 8, 2017).

Back to Citation 16.

                     This proposed action is based on the information contained in the administrative record for this action and does not prejudge any future EPA action that may make other determinations regarding the air quality status in New York and downwind states. Any such future action, such as action on a CAA section 126(b) petition or area designations under any NAAQS, would be based on separate administrative records and the EPA's analyses of information that becomes available at that time. Future available information may include, monitoring data and modeling analyses conducted by states, air agencies, and third-party stakeholders.

Back to Citation 17. Cf. Genon Rema v. EPA, 722 F.3d 513 (3d Cir. 2013) (upholding EPA grant of CAA section 126(b) petition and establishment of direct federal emissions control requirements on SO 2 source in Pennsylvania found to be significantly contributing to nonattainment and interfering with maintenance of the 2010 SO 2 NAAQS in New Jersey).

Back to Citation 18. 70 FR 25162 (May 12, 2005).

Back to Citation 19. North Carolina v. EPA, 531 F. 3d 896, 901 (D.C. Cir. 2008), modified on reh'g, 550 F. 3d 1176 (D.C. Cir. 2008).

Back to Citation 20.

                     550 F. 3d at 1178.

Back to Citation 21. 76 FR 48207 (August 8, 2011).

Back to Citation 22.

                     CSAPR has been subject to extensive litigation, and on July 28, 2015, the D.C. Circuit issued a decision generally upholding CSAPR but remanding without vacating the CSAPR emissions budgets for a number of states. New York's ozone season NO X budgets were not included in the remand. *EME Homer City Generation* v. *EPA,* 795 F.3d 118, 138 (D.C. Cir. 2015). On October 26, 2016, we finalized an update to CSAPR that addresses the 1997 ozone NAAQS portion of the remand as well as the CAA requirements addressing interstate transport for the 2008 ozone NAAQS. [81 FR 74504](https://www.federalregister.gov/citation/81-FR-74504) (October 26, 2016).

Back to Citation 23.

                     In *North Carolina* v. *EPA,* 531 F.3d at 910-911 (D.C. Cir. 2008), the D.C. Circuit explained that the regulating authority must give Prong 2 “independent significance” from Prong 1 by evaluating the impact of upwind state emissions on downwind areas that, while currently in attainment, are at risk of future nonattainment.

Back to Citation 24.

                     EPA's NEI is available and accessible to the public at *[https://www.epa.gov/​air-emissions-inventories/​national-emissions-inventory](https://www.epa.gov/air-emissions-inventories/national-emissions-inventory).*

Back to Citation 25.

                     The EIS is EPA's database used to receive and store emissions data and generate emissions inventories. The EIS Gateway is a web-based tool developed to provide only registered EPA, State, local and Tribal users with access to emission inventory data for sources in their jurisdiction.

Back to Citation 26.

                     
                    See 
                     Table 9 in the EPA's TSD.

Back to Citation 27.

                     EPA notes that the evaluation of other states' satisfaction of section 110(a)(2)(D)(i)(I) for the 2010 1-hour SO 2 NAAQS can be informed by similar factors found in this proposed rulemaking but may not be identical to the approach taken in this or any future rulemaking for New York, depending on available information and state-specific circumstances.

Back to Citation 28.

                     A detailed review of EPA's evaluation of emissions, air monitoring data, other technical information, and rationale for proposed approval of this SIP revision as meeting CAA section 110(a)(2)(D)(i)(I) for the 2010 1-hour SO 2 NAAQS may be found in the TSD.

Back to Citation 29.

                     The physical properties of SO 2 result in relatively localized pollutant impacts near the emissions source. Therefore, the EPA selected a spatial scale with dimensions up to 50 km from point sources.

Back to Citation 30.

                     The design value is the 3-year average of the 99th percentile 1-hour daily maximums at a monitor. A control strategy should be designed to bring the value to attainment of the standard.

Back to Citation [FR Doc. 2026-06938 Filed 4-9-26; 8:45 am]

BILLING CODE 6560-50-P

Published Document: 2026-06938 (91 FR 18341)