TX222.22 Air Quality State Implementation Plans; Approvals and Promulgations: Texas; Reasonably Available Control Technology in the Dallas-Fort Worth Ozone Nonattainment Area,[...]

Air Plan Approval; Texas; Reasonably Available Control Technology in the Dallas-Fort Worth Ozone Nonattainment Area

SUPPLEMENTARY INFORMATION:

Throughout this document "we," "us," and "our" means the EPA.

I. Background

The background for this action is discussed in detail in our July 24, 2025  ⁽¹⁾ and September 5, 2025  ⁽²⁾ proposals (referred to as the "proposals"). In those actions we proposed to approve Texas' May 13, 2020, RACT SIP revision and May 12, 2020, SIP revision to 30 TAC Chapter 115 and Chapter 117 as meeting the 2008 8-hour ozone Serious classification RACT level control requirements consistent with section 172(c)(1) and 182 of the CAA. The EPA's July 24, 2025, action proposed to determine that the Texas SIP revisions fulfill the Serious NO _X RACT requirements for the DFW NAA for the 2008 ozone NAAQS and to approve the concurrent Chapter 117 rule revisions. The EPA's September 5, 2025, action proposed to determine that the Texas SIP revisions meet the Serious RACT requirements for CTG and non-CTG VOC major sources  ⁽³⁾ for the 2008 ozone NAAQS and to approve the concurrent Chapter 115 rule revisions. The relevant Texas SIP revisions included Texas' finding that previously approved federally enforceable limits on cement kilns continue to fulfill RACT requirements, and CTG RACT negative declarations for the following categories of sources fiberglass boat manufacturing materials, surface coating for flat wood paneling, letterpress printing, shipbuilding and ship repair surface coating operations, vegetable oil manufacturing, and rubber tire manufacturing categories. Texas also submitted negative declarations for several CTG categories for Wise County: graphic arts-rotogravure and flexography, flexible package printing, refinery vacuum producing systems and process unit turnarounds, wood furniture manufacturing, and manufacture of synthesized pharmaceutical products. Texas stated in its May 13, 2020, submittal that it did not locate any major sources subject to the NO _X Emissions from Nitric or Adipic Acid Manufacturing Alternative Control Techniques (ACT) document. The EPA has already taken final action through a different rulemaking process to approve the requirement for implementation of RACT for sources covered by the 2016 Oil and Natural Gas Industry Control Techniques Guidelines (CTG). ⁽⁴⁾

During the EPA's July and September 2025 public comment periods, the EPA received a total of six comments on our proposals. As explained in further detail below, several comments were received on a NO _X Technical Support Document (TSD) that is not associated with this action and those comments do not reflect our evaluation of Texas' RACT SIP submittal or current Texas rules. In the NO _X TSD associated with this action, the EPA gathered and analyzed relevant information including Texas' rulemaking record which contained information on specific control technologies and technical and economic feasibility for the Emissions Specifications for Attainment Demonstration (ESAD) rates, Texas Register documents which included Texas' response to comments on the rulemaking, and recent documents issued by EPA (such as the 2017 OTC Draft White Paper on Control Technologies, OTC State Regulations from Eight Source Categories, 2019 OTC State Regulations from Eight Source Categories, and 2019 OTC Regulatory and Technical Guideline for Control of Nitrogen Oxides (NO _X ), and Emissions from Natural Gas Pipeline Compressor Fuel‐Fired Prime Movers). In the VOC TSD for this action, the EPA gathered and analyzed relevant information including comparing Texas' CTGs and non-CTG major source RACT rules to other relevant state VOC RACT rules, and reviewed EPA's RACT/BACT/LAER Clearinghouse (RBLC), NSPS, MACT standards, and NESHAPs, where applicable. Consistent with this analysis, we proposed to determine that Texas' EPA-previously-approved Chapters 115 and 117 rules still fulfill the RACT level of control requirements for sources of VOC and NO _X in the DFW Serious ozone nonattainment area for the purpose of the 2008 ozone NAAQS.

In this final action, we are responding to comments received on both NO _X and VOC proposals. The comments are available in the docket for this action.

II. Response to Comments

A. Disproportionate Impacts of NAAQS Violations to Communities

Comment: Commenters stated that the EPA failed to incorporate environmental justice analyses.

Response: First, the EPA notes that Executive Order 14148, "Initial Rescission of Harmful Executive Orders and Actions" (90 FR 8237, January 28, 2025), revoked certain past Executive Orders that specifically addressed environmental justice concerns, including Executive Order 12898 and Executive Order 14094. Further, under section 110(k)(3) of the CAA, the EPA is required to approve a SIP submission that complies with the provisions of the CAA. The EPA has determined that the RACT SIP submittals at issue in this action meet all applicable requirements of the CAA, and therefore the EPA is finalizing approval of the relevant SIP revisions. Implementation of RACT is designed to assist with improving air quality in the nonattainment area.

B. Concerns Regarding RACT Control Technologies and Determination

Comment: Commenters claim that the EPA provided a cursory NO _X RACT analysis in its TSD.

Response: As an initial note, commenters appear to be commenting on a TSD that is not associated with this action and is neither fully cited nor made available for additional reference purposes by commenters. Specifically, commenters reference a document titled "EPA Technical Support Document (TSD), Oxides of Nitrogen (NO _X ) Reasonably Available Control Technology (RACT): Dallas-Fort Worth (DFW) 2008 8-Hour Ozone Nonattainment Area," Docket No" (the commenters' reference does not include a docket number). Furthermore, in some comments, commenters reference TSD page numbers that are greater than 27 pages, which is the length of the TSD for this action.

The commenters reference a TSD that is not the NO _X TSD that the EPA published in the docket for the proposed rulemaking. The NO _X TSD for the proposed rulemaking is titled, "Technical Support Document, Reasonably Available Control Technology Application Analysis for Nitrogen Oxides in the Dallas-Fort Worth 2008 Ozone Serious Nonattainment Area."

The commenters' reference to an unrelated TSD is evidenced further by other comments, which will be addressed on a comment-by-comment basis in this Response to Comments section. However, even if commenters were referring to the correct TSD, the EPA still disagrees with the comment. The EPA's TSD provides an extensively detailed evaluation of Texas' NO _X RACT limits that includes a review and comparison to recent Best Available Control Technology (BACT) determinations in the RBLC, recent documents issued by the EPA to compare to Texas' SIP submittal, and rules in other states where similar sources exist in nonattainment areas to support our approval. ⁽⁵⁾

Comment: Commenters claim that Texas failed to impose new RACT emissions limits in Wise County, despite such limits being technologically and economically feasible.

Response: Referencing the incorrect TSD, commenters make a broad general claim regarding all RACT limits in Wise County. This general comment did not provide any technological or economic feasibility information specific to any limit for any category of sources to support their cursory statement for sources in Wise County. We note that other comments with greater specificity to the type of source and specific limits were received and our responses to those comments follow below in this document. The EPA's NO _X TSD (available in the docket for this action) details relevant information, including BACT, RACT rules in other states, the 2019 OTC Regulatory and Technical Guideline for Control of Nitrogen Oxides (NO _X ) Emissions from Natural Gas Pipeline Compressor Fuel‐Fired Prime Movers, the 2017 OTC Draft White Paper on Control Technologies, and OTC State Regulations from Eight Source Categories, considered in support of our proposed approval of the Wise County RACT rates (pages 9-12 of the NO _X TSD).

Comment: Commenters claim that the EPA's TSD states that the EPA is conditionally approving the NO _X RACT limits for the Martin Marietta Cement plant and that these limits are not part of the SIP submission.

Response: Commenters appear to be commenting on an unrelated TSD to this action. The EPA took final action to fully approve these limits into the SIP on February 22, 2019 (84 FR 5601).

C. Control Technologies

Comment: Commenters state that NO _X emissions limits in California's South Coast Air Quality Management District (SCAQMD) for electric generating units (EGUs) are lower than Texas' RACT rules. Commenters point to the SCAQMD's 2022 proposal of Rule 1135(d)(1) table 1, which limits NO _X emissions from EGUs to 5 parts per million by volume (ppmv) and lower. Commenters claim, with specific TSD page references, that the EPA's TSD does not address RACT for gas-fired EGUs and only references the 1994 Alternative Control Techniques (ACT) for utility boilers.

Response: Similar to previous comment responses in this document, commenters reference specific pages of an unrelated TSD to support their comment. Again, the specific pages referenced in their comment do not correspond to the TSD associated with this action. The EPA's NO _X TSD associated with this action does not reference the 1994 ACT as the basis for our approval. The EPA disagrees that our NO _X TSD fails to address EGUs (see pages 24-26 of the NO _X TSD included in the docket).

Based on the information made available in the docket for this action and in consideration of the comment received, we are responding to provide additional clarity concerning the SCAQMD Rule 1135(d)(1) limit, aside from the commenters review of the unrelated TSD and rules. The SCAQMD Rule 1135(d)(1) is titled "Emissions Limits for Boilers and Gas Turbines", and states that the emissions limits in table 1 apply "On and after January 1, 2024". In response to this comment, EPA reviewed SCAQMD's 2018 "Draft Staff Report, Proposed Amended Rule 1135" (the "Staff Report"). ⁽⁶⁾ Of particular relevance in our review of the Staff Report, is SCAQMD's determination that it has the authority to require equipment replacement to meet state emissions standards: "SCAQMD retains broad statutory authority to adopt emission-control requirements for stationary sources, and that authority may require equipment replacement, as long as the requirement is not arbitrary and capricious."  ⁽⁷⁾

With respect to boilers, the Staff Report examines all of the natural gas boilers to which the limit would apply. The Staff Report states that "18 of 23 natural gas boilers are planned to be shutdown. Of those 18 natural gas boilers, all but four of them will be shut down by January 1, 2024. . . . Another . . . two natural gas boilers scheduled for shutdown in 2025 and the two natural gas boilers scheduled for shutdown in 2029. Three natural gas boilers are expected to be repowered to natural gas turbines or renewable power sources. However, if they are not, they will be required to meet the proposed limit. . . . The last two natural gas boilers have not been in operation since 2012." The EPA notes that of the affected natural gas boilers, 20 out of 23 sources will meet the Rule 1135(d)(1) limit through shutdowns. The EPA also notes that the remaining three are expected to be either converted to natural gas-fired turbines (thus will no longer be boilers) or repowered to renewable power sources (thus will no longer be gas-fired). Notably, the Staff Report does not include any evaluation or even identification of any "reasonably available control technology considering technical and economic feasibility"  ⁽⁸⁾ that could be applied to these existing gas-fired boiler units to meet the Rule 1135(d)(1) limit with the unit continuing to remain a natural gas-fired boiler.

It appears that the Rule 1135(d)(1) limit that commenters claim to be RACT for natural gas-fired boiler EGUs is actually a specific RACT limit for natural gas-fired boiler EGUs that will be converted to natural gas-fired turbines or repowered to renewables, but we do not agree that Rule 1135(d)(1) limits are RACT for natural gas-fired boiler EGUs where the state does not require conversion to natural gas-fired turbines or repowering to renewables for this category of sources to meet RACT. Therefore, SCAQMD Rule 1135(d)(1) is not comparable to Texas' Chapter 117.1310 limits due to the differences in the category of sources regulated.

For natural gas-fired utility boilers, our NO _X TSD (see pages 24-26) detailed relevant information considered, including but not limited to, EPA's 2023 EGU NO _X Mitigation Strategies Final Rule TSD and RACT rules in other states for this category of sources. EPA concluded that Texas' ESAD limits for utility boilers are comparable to performance of Selective Catalytic Reduction (SCR) on gas-fired utility boilers and fulfill RACT requirements.

With respect to stationary gas turbine EGUs, the Staff Report examines both natural gas combined cycle and simple cycle gas turbines. All of the combined cycle gas turbines are equipped with selective catalytic reduction (SCR) pollution control equipment, and 15 out of 23 units are already permitted at 2 parts per million (ppm), which is the Rule 1135(d)(1) limit for this category of sources. Of the remaining 8 units, two are limited to 2.5 ppm and the remaining units have limits ranging from 7 ppm-9 ppm. For simple cycle gas turbines, out of the total 59 units, all but two are equipped with SCR. The two units without SCR are used sporadically to support renewable power generation and can use the low-use provisions to be exempt from the limit. For the remaining 57 SCR equipped units, 37 units are permitted at or below the Rule 1135 limit of 2.5 ppm, and 20 units are equipped with SCR and have a permit emission limitation of 5 ppm.

It appears that the Rule 1135(d)(1) limits, which commenters claim to be RACT for all stationary gas turbine EGUs, may be RACT specifically for stationary gas turbines with SCR EGUs that are already permitted at or near Rule 1135(d)(1) rates, but we do not agree these rates are RACT for existing units without SCR where the state does not require replacement to meet state limits. Therefore SCAQMD Rule 1135(d)(1) rates are not comparable to Texas' Chapter 117.1310 limits due to the differences in the category of sources regulated.

As detailed on page 26 of our NO _X TSD for stationary gas turbines EGUs, the EPA reviewed relevant information, including 2017 OTC Draft White Paper on Control Technologies and OTC State Regulations from Eight Source Categories and RACT rules in other states, in support of our approval.

Comment: Commenters claim Texas fails to establish RACT for gas-fired boilers and process heaters because Texas' RACT limits for gas-fired boilers are higher than other state's RACT rules. In support of their claim, commenters refer to California SCAMQD Rule 1146(c)(1)(A) which limits NO _X from industrial boilers and process heaters to a NO _X limit of 0.035 lb/MMBtu or lower, and a New York State NO _X RACT limit of 0.05-0.08 lb/MMBtu for gas-fired boilers.

Response: SCAQMD Rule 1146 applies to boilers, steam generators, and process heaters. Specifically, SCAQMD Rule 1146(c)(1)(A) applies to "All Units Fired on Gaseous Fuels". Under the Texas rules, 30 TAC Chapter 117.410 regulates process heaters and gas-fired boilers as separate categories. Considering the significant differences in the applicability of Rule 1146(c)(1)(A) and the applicability of Texas' Chapter 117.410 rates (explained further below), the EPA disagrees with commenters claims regarding natural gas-fired boilers and process heaters for categories of sources in nine of the ten DFW NAA Counties. For these two categories of sources, Texas' Chapter 117.410 includes ESAD limits that are applicable to nine out of ten counties included in the DFW NAA. These Texas ESAD rates include a range of limits and are comparable to SCAQMD's Rule 1146(c)(1)(A) rates and lower than the New York State RACT rule cited by the commenters (see pages 12 and 14 of the NO _X TSD). The remaining county in the DFW NAA, Wise County, does not have any gas-fired boilers.

With respect to process heaters in Wise County, EPA notes that SCAQMD 1146 (c)(1)(A) rule applies to "all units firing gaseous fuels" and the rule is applicable to "boilers, steam generators, and process heaters", not solely to process heaters. The EPA further notes that "process heaters" have a different definition than "thermal fluid heaters". In response to this comment, EPA reviewed the record associated with the development of the limits in SCAQMD Rule 1146. ⁽⁹⁾ The SCAQMD "Final Staff Support" report extensively documents the testing data of the units to which these limits apply. ⁽¹⁰⁾ There was no discussion on "process heaters" in the Final Staff Support document, thus EPA is unable to verify that any process heaters exist or were considered in setting the limit for Rule 1146(c)(1)(A) "All Units" limit that commenters claim to be RACT for process heaters. It appears that SCAQMD's Rule 1146(c)(1)(A) that commenters claim to be RACT for process heaters is actually RACT specifically for gaseous fuel fired boilers and steam generators and not process heaters. Therefore, SCAQMD's Rule 1146(c)(1)(A) is not comparable to Texas' Chapter 117.410 limits due to the differences in the category of sources regulated.

Thermal fluid heaters can be considered a subcategory of process heaters and are subject to SCAQMD Rule 1146(c)(1)(L) (which commenters do not cite, but we discuss here since it regulates a subcategory of process heaters). In the Final Staff Support document, there was a discussion on "thermal fluid heaters", which states that "Source tests records from a total of 14 thermal fluid heaters ranging from 2 MMBtu/hr to 10 MMBtu/hr with emissions limit of 30 ppm were evaluated. Five out of 14 units source tested substantially (>64%) below the permit limit. Out of the five units, 3 units were new or modified equipment permitted at BACT and 2 units utilized burner replacements. This shows that it is technically feasible for thermal fluid heaters applicable to Rule 1146.1 and Rule 1146 thermal fluid heaters to achieve an emission level of 12 ppm with burner replacements after providing at least 10% buffer for rule compliance."  ⁽¹¹⁾ The EPA notes that only "thermal fluid heaters" already achieving 30 ppm were evaluated and that the Rule 1146 limit could only be achieved with burner replacements of existing units having undergone a "major modification" to trigger the installation of control equipment that met BACT requirements. It appears that SCAQMD determined existing units could not meet these limits without BACT level control. As a result, SCAQMD Rule 1146(c)(6) extends the date of compliance for existing sources as far out as 2033; for units permitted to construct or permitted to operate prior to "December 7, 2018, must meet the limits in Rule 1146(c)(1) by 2033 or when 50% or more of the unit's burners are replaced whichever is earlier." It further appears that SCAQMD 1146(c)(1)(L) may be RACT for existing units with emissions limits of 30 ppm and will have a 50% burner replacement at some future date, but we do not agree that these rates are RACT for existing process heaters where the state does not require a 50% burner replacement at some future date to meet a future compliance date. Therefore, SCAQMD Rule 1146 (c)(1)(L) is not comparable to Texas' Chapter 117.405 limits for Wise County due to the differences in the category of sources regulated. The EPA's NO _X TSD details relevant information, including RACT rules in other states and economic and technical feasibility issues considered by Texas in support of our approval for the Wise County RACT limits for process heaters (see page 10 of the NO _X TSD).

Comment: Referencing pages 37 of a TSD, commentors claim that EPA's TSD only considered the 1994 ACT for process heater and industrial boilers.

Response: Commenters again reference specific pages of an unrelated TSD to support the basis of their comment. As the EPA has previously detailed in this document, the specific pages referenced by the commentor do not correspond to the TSD associated with this action and included in the docket for this action. The EPA's NO _X TSD associated with this action does not reference the 1994 ACT as the basis for our approval. The EPA's analysis of process heaters (see pages 10 and 14 of the NO _X TSD) did not consider the 1994 ACT. The EPA considered and discussed in a previous response, the relevant information and consideration for the process heaters category of sources in support of its proposed approval for this category of sources.

Comment: Commenters provided comments related to the SCAQMD's Rule 1134, Emissions of Oxides of Nitrogen From Stationary Gas Turbines, and specifically Rule 1134(d)(3) related to Emissions Limitations. Commenters state that SCAQMD's Rule 1134(d)(3) applicability threshold starts at 0.3 megawatt (MW) stationary gas turbines and that Texas only sets limits for 10 MW or greater units. Commenters claim that Texas' limits are higher than SCAQMD's Rule 1134, which range from 2-12.5 ppm. Commenters also included specific comments related to turbine units located in Bexar County and Wise County. In Bexar County, commenters stated that turbine units must be subject to RACT. For Wise County, commenters claim that the TSD quotes reasoning from Texas for limits in Wise County and generalized arguments about the cost of implementing retrofit technology without providing adequate support. Commenters reference specific page numbers from a TSD to claim that the TSD cites information from 1994 and prior RACT approval.

Response: As previously detailed in this action, commenters are referencing specific pages of an unrelated TSD and the EPA's NO _X TSD associated with this action does not reference the 1994 ACT as the basis for our approval. EPA disagrees that its NO _X TSD cited information from 1994 and prior RACT approvals as the basis for our approval. Commenters cited to pages that are not present in our NO _X TSD that was included in the docket. The EPA also disagrees that Texas' limits are only applicable to stationary gas turbines greater than 10 megawatts (MW); commenters appear to be commenting on threshold applicability rules that do not exist for the DFW NAA. RACT for Bexar County is outside the scope of this action because Bexar County is not part of the DFW NAA. The DFW NAA under the 2008 8-hour ozone NAAQS includes the counties of Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, Tarrant, and Wise.

Based on the information made available in the docket for this action and consideration of the comment received, we are responding to provide additional clarity concerning stationary gas turbines. All existing stationary gas turbines are regulated in the DFW NAA under Chapters 117.405 and 117.410.

SCAQMD Rule 1134(d)(3) which commenters claim to be RACT, states that the table 1 limits are applicable "On and after January 1, 2024, or when required by a Permit to Construct or Permit to Operate, whichever occurs first". The EPA notes that a Permit to Construct is required for new sources and does not apply to existing sources.

SCAQMD Rule 1134(d)(3) table 1 lists five different stationary gas turbine limits that vary depending on the type of turbine (simple or combined cycle), and type of fuel (natural gas, pipeline gas, produced gas, or other gas). Texas Chapter 117.405 and Chapter 117.410 apply limits based only upon the turbine's size. As such, EPA believes that the limits cannot be directly compared because Texas may not have all of the same types of stationary gas turbines as SCAQMD. The EPA notes that Texas' limit of 0.032 lb/MMbtu (which converts to 9 ppm) for the largest size of stationary gas turbine, in nine of the DFW NAA Counties, is comparable to SCAQMD's limit of 8 ppm for Natural Gas Simple Cycle Pipeline Gas Turbines.

In response to this comment, the EPA reviewed SCAQMD's 2018 "Preliminary Draft Staff Report, Stationary Gas Turbines" (the "Preliminary Draft Staff Report"). ⁽¹²⁾ Table 2-2, Natural Gas Combined Cycle Gas Turbines, identifies information on the sources in this category. The EPA's review notes that all but one of units appear to be operating at or just above the limits provided for in Rule 1134(d)(3) for sources that commenced operation in 2009 or later, equipped with SCR as new or replacement units. Preliminary Draft Staff Report, Table 2-3-Natural Gas Simple Cycle Gas Turbines identifies the information on sources in this category. All but two of the units permitted at 5 ppm or lower have SCR and were installed in 2001. SCAMQD recognizes that a unit would have to be a new or replacement unit with SCR by providing a low-use provision in Rule 1134(h)(4) for existing units without SCR that are unable to meet the limit without replacement. Furthermore, the Preliminary Draft Staff Report discusses SCAQMD's determination that it has the authority to require equipment replacement to meet state emissions standards: "The SCAQMD retains broad statutory authority to adopt emission-control requirements for stationary sources, and that authority may require equipment replacement, as long as the requirement is not arbitrary and capricious."  ⁽¹³⁾

It appears that the use of SCR either as a new installation or as a replacement unit is the basis of Rule 1134(d)(3) limits. While Rule 1134(d)(3) limits may be RACT for gas-fired turbines with SCR where the state requires existing units to be replaced to meet RACT, we do not agree that Rule 1134(d)(3) limits are RACT for existing gas-fired turbines where the state does not require units to be replaced to meet RACT. Therefore, SCAQMD Rule 1134(d)(3) is not comparable to Texas' Chapter 117.405 and 117.410 due to the differences in sources regulated.

As detailed in our analysis in the NO _X TSD, Texas stated that "Compliance with the emission specification of 0.032 lb/MMBtu for stationary gas turbines and duct burners used in turbine exhaust ducts may require the installation of SCR. The emission specifications for all stationary gas turbines . . . are expected to be achievable through combustion modifications such as water or steam injection or other modifications". ⁽¹⁴⁾

Texas considered the same technologies as identified as SCAQMD when determining the Chapter 117.410 ESAD rates for the nine DFW NAA counties. However, applying the same control technology to existing units and achieving the same rate as a new or replacement unit subject rates presents reasonable technological and economic feasibility issues.

For Chapter 117.405 rates in Wise County, Texas stated "These limits for industrial gas turbines are based on . . .comments and supplemental information provided by affected source owners and operators: retrofit options or kits to reduce NO _X emissions may not exist for some of these particular makes and models; some units have already been retrofitted with dry low-NO _X combustors to reduce emissions and thus may be unable to further reduce NO _X emissions; and in some cases the cost to retrofit the unit may be more than the cost of a new unit. . . Additional information provided by commenters indicated unit performance variability among various turbine model ratings, and stack test data provided by an affected source owner or operator for specific units identified in Wise County, indicated greater unit-specific performance variability. The commission therefore determined that 0.55 lb/MMBtu for units rated less than 10,000 hp is an appropriate RACT control level considering current performance levels of existing units in Wise County". ⁽¹⁵⁾

As detailed in the NO _X TSD on pages 11-12 for Wise County and pages 15-16 for the other nine DFW NAA Counties, the EPA considered relevant information, including the 2017 OTC Draft White Paper on Control Technologies and OTC State Regulations from Eight Source Categories, 2019 OTC Regulatory and Technical Guideline for Control of Nitrogen Oxides (NO _X ) Emissions from Natural Gas Pipeline Compressor Fuel‐Fired Prime Movers, and RACT rules in other states in support of its proposed approval of Texas' limits for this category of sources.

Comment: Commenters claim that Texas fails to establish RACT for gas-fired, stationary, internal combustion engines. Commenters state that the State of New York limits gas-fired, stationary internal combustion engines with a mechanical output rating of 200 bhp or greater to 1.5 g/bhp-hr which applies to rich-burn and lean-burn engines. Commenters claim that Texas' rule does not cover lean-burn engines. Commenters also claim that the EPA's TSD provided no support for our proposed approval and cited information from 1994 and previous approvals. Commenters cite to pages in a TSD in support of their statements.

Response: Based on the information made available in the docket for this action and consideration of the comment received, we are responding to provide additional clarity concerning RACT for gas-fired, stationary, internal combustion engines. Again, as previously detailed in this action, commenters are referencing specific pages of a TSD that is not associated with this action. The New York State rule that commenters cite is applicable to 200 hp or greater engines. This limit from a New York State rule is for engines that are only fired with natural gas. New York State's RACT limits for engines that are fired with other types of fuel range from 2.0-2.3 grams per brake hp-hr (g/bhp-hr). Unlike New York State's rule, which has a size applicability threshold, Texas' limits for stationary internal combustion engines apply to all engines. Texas' limits for rich-burn engines in nine of the ten counties in the DFW NAA are lower than New York State's RACT limit (see page 14 of the NO _X TSD). Texas' limits in Wise County are comparable to the New York State rule (see pages 10-11 of the NO _X TSD).

Commenters incorrectly claim that Texas' rules do not cover lean-burn engines. Texas' Chapter 117.405 and 117.410 rules limit NO _X emissions from lean-burn engines and these emission limitations apply to all sizes of engines, not just those of 200 brake hp or greater (see pages 10-11, and 14 of the NO _X TSD). Texas presented economic considerations in setting the rate for pre-2015 lean-burn engines in Wise County (discussed in detail in a later comment in this action). Texas does not apply different limits for different fuels, unlike New York State's rule. Wise County's RACT rate for post-2015 engines, 2.0 g/hp-hr, is comparable to New York's RACT rates considering all fuel types. For the other nine counties in the DFW NAA, all ESAD rates for lean-burn engines are lower than New York State's RACT rule (see pages 10-11, and 14 of the NO _X TSD). The EPA disagrees that our NO _X TSD cited 1994 information and past approvals as the basis for its proposed approval. The NO _X TSD for this action details our review of relevant information, including 2019 OTC Regulatory and Technical Guideline for Control of Nitrogen Oxides (NO _X ) Emissions from Natural Gas Pipeline Compressor Fuel‐Fired Prime Movers, 2017 OTC Draft White Paper on Control Technologies and OTC State Regulations from Eight Source Categories and RACT rules in other states for this category of sources. Commenters appear to have reviewed a TSD other than the one associated with this action.

Comment: Commenters made a claim that, for gas-fired stationary engines where Texas and the EPA believes that existing rules constitute RACT, they must provide justification that stronger controls are infeasible. Commenters claim that the cost of these controls must be computed in order to know whether the retrofit would be economically feasible. Commenters state that Texas acknowledges that the limits adopted for Wise County are less stringent than elsewhere in the DFW area.

Response: Commenters present no new technologies or other RACT limits that are lower than the ESAD limits in nine out of the ten counties in the DFW NAA for this category of sources. Commenters also do not present any cost data demonstrating the economic feasibility of new retrofit technologies for sources in Wise County. The EPA acknowledges that the Wise County RACT rates for lean burn engines appear to be higher than the other nine counties' ESAD limits. While the Wise County RACT rates for lean burn engines appear to be higher than the ESAD limits for the other nine counties in the DFW NAA, Texas addressed this issue in their rulemaking record. Specifically, Texas stated that requiring the same limits in Wise County "may necessitate the installation of SCR technology. SCR would cost more than the technologies already evaluated for the particular stationary engines in Wise County, and would likely result in the replacement of many of the gas-fired lean-burn engines in Wise County. Such an outcome is contrary to the definition of RACT, i.e., the lowest emission limitation that a particular source is capable of meeting by the application of control technology that is reasonable available considering technological and economic feasibility. A control level cannot represent RACT for a "particular source" if it is more cost effective to replace that source with an entirely new source in order to meet the emission limitation. Additionally, the commission is allowed to make source-specific RACT determinations, as the definition of RACT states. The commission contends that the NO _X emission specifications in adopted § 117.405(b)(2)(B) present RACT for the particular gas-fired lean-burn engines in Wise County."  ⁽¹⁶⁾

As stated on page 11 of the NO _X TSD, EPA reviewed recent information including, New York State's RACT limit, 2019 OTC Regulatory and Technical Guideline for Control of Nitrogen Oxides (NO _X ) Emissions from Natural Gas Pipeline Compressor Fuel‐Fired Prime Movers, 2017 OTC Draft White Paper on Control Technologies and OTC State Regulations from Eight Source Categories, and Texas' rulemaking records, in support of its proposed approval of the Wise County RACT limits and ESAD limits for this category of sources (see pages 11 and 14 of the NO _X TSD).

D. Notice & Comment

Comment: Commenters claim that the EPA's Federal Register publication is inadequate, because the proposal does not identify the specific facilities that are the subject of the rule making and a person would have no way of knowing whether to be "interested" in the rule making without resorting to the technical support document in the docket.

Response: The EPA disagrees with the comment. We are required to provide adequate notice to the public and interested parties, and we did this through publishing a document in the Federal Register , where we outlined Texas' RACT program featuring rules for specific industry sectors. In that notification, we also provided our analysis to support why Texas' SIP revisions and existing rules fulfill the Serious RACT requirements for the DFW nonattainment area for the 2008 ozone NAAQS. Finally, in our document we provided a link to the online docket that contains all of the supporting materials, and EPA's technical support documents that contain our extensive analysis of the Texas RACT program.

This approach to public notice is consistent with EPA's previous proposed approval for the Moderate RACT requirements for the DFW nonattainment area for the 2008 ozone NAAQS (82 FR 33026 (July 19, 2017)), and EPA's recent RACT proposed approval actions. ⁽¹⁷⁾

Comment: Commenters state that the notification is inadequate because, according to the Office of the Federal Register, proposed rulemaking must provide "a statement of the proposed rule's basis and purpose . . . in plain language that the reader can easily understand."

Response: Based on the information provided by the commenter, it is unclear how the information provided by the EPA failed to meet the direction provided by the Office of the Federal Register. In the EPA's proposals for this action, the EPA provided background information, an explanation of Texas' SIP submission, the EPA's analysis, and the proposed publications. The proposals were further supplemented by technical support documents for both NO _X and VOC emissions.

Comment: Commenters refer to the Office of Federal Register's "Document Drafting Handbook"  ⁽¹⁸⁾ (DDH) and state that the document must include a physical mailing address for persons who wish to submit comments by mail and noted that the EPA's proposed rulemaking does not include this information.

Response: The DDH states that all proposed rulemakings "must have at least one address."  ⁽¹⁹⁾ The DDH then provides a list of potential addresses that an agency could use, including addresses for mailing public comments, sending public comments electronically, hand-delivering public comments, or attending a public hearing (or meeting). In the proposals for this action, the EPA properly complied with the DDH by offering an address to send public comments electronically (via www.regulations.gov ), and by providing an email address where a potential commenter could contact the EPA staff contact to submit comments via alternative methods.

E. Texas Commission on Environmental Quality (TCEQ) Comments

The EPA received comment letters from the TCEQ in support of our proposals. TCEQ requested clarification and administrative corrections to the VOC and NO _X TSDs.

VOC TSD

TCEQ requested the following corrections to the VOC TSD:

• In table 2 on page 6, TCEQ requests the EPA correct the CTG Reference Document for Cutback Asphalt, which is mislabeled as Control of Volatile Organic Emissions from Bulk Gasoline Plant.
• In table 2 on page 7, TCEQ requests the EPA correct the CTG Reference Document for Petroleum Liquid Storage Fixed Roof Tanks CTG to document number EPA-450/2-77-035.
• In the Stage 1 Vapor Control Systems (1975) table on page 32 of the TSD, TCEQ requests the EPA remove the floating roof tank from the Texas Requirement Summary. While a floating roof tank may be an equivalent control under 30 TAC § 115.223, this control option is not specifically mentioned in 30 TAC §§ 115.221-115.229.
• In the Tank Truck Gasoline Loading Terminals (1977) table on page 40 of the TSD, TCEQ requests the EPA remove the floating roof tank from the Texas Requirement Summary. While a floating roof tank may meet the 90% control requirement at 30 TAC § 115.212 or be considered an equivalent control under 30 TAC § 115.213 or 30 TAC § 115.223, it is not specifically mentioned in 30 TAC §§ 115.211-115.219 or 30 TAC §§ 115.221-115.229.

• In the Surface Coating of Metal Furniture (1977) and Metal Furniture Coatings (2007) table on page 42 of the TSD, TCEQ requests that the EPA add 30 TAC §§ 115.450-115.459 to the Texas Requirement Summary. TCEQ implemented the 1977 CTG in 30 TAC §§ 115.420-115.429 and the 2007 CTG in 30 TAC §§ 115.450-115.459. The EPA's stated range of 2.3 to 5.1 pound per gallon (lb/gal) applies to 30 TAC § 115.453. The correct limit in 30 TAC § 115.421(2) is 3.0 lb/gal.

• In the Bulk Gasoline Plants (1977) table on pages 45-46 of the TSD, TCEQ requests the EPA remove the floating roof tank from the Texas Requirement Summary. While a floating roof tank may meet the 90% control requirement at 30 TAC § 115.212(a)(5) or be considered an equivalent control under 30 TAC § 115.213, it is not specifically mentioned in 30 TAC §§ 115.211-115.219.
• In the Surface Coating of Miscellaneous Metal Parts and Products (1978) and Control Techniques for Miscellaneous Metal Parts Coatings (2008) table on page 50 of the TSD, TCEQ requests the EPA add 30 TAC §§ 115.450-115.459 to the Texas Requirement Summary. TCEQ implemented the 1978 CTG in 30 TAC §§ 115.420-115.429 and the 2008 CTG in 30 TAC §§ 115.450-115.459.
• In the Graphic Arts-Rotogravure and Flexography table on pages 55-56 of the TSD, TCEQ requests the EPA correct the Texas Requirement Summary. TCEQ rules contain a requirement for 90% control of captured vapors and capture requirements for various printing processes ranging from 60% to 75%.
• In the Petroleum Liquid Storage in External Floating Roof Tanks (1978) table on page 57 of the TSD, TCEQ requests the EPA correct the Texas Requirement Summary. TCEQ rules in 30 TAC §§ 115.110-115.119 require various combinations of a submerged fill pipe, floating roof, floating roof with seals, and/or a vapor control system based on the vapor pressure of the liquid stored and size of the tank.
• In the Aerospace (1997) table on pages 70-71 of the TSD, TCEQ requests the EPA correct the Texas Requirement Summary. TCEQ rules in 30 TAC §§ 115.420-115.429 require VOC content limits ranging from 60 to 1,230 grams per liter. The cleaning solvents used must be over 80% water by volume or have a composite vapor pressure less than or equal to 45 millimeters of mercury at 20 degrees Celsius. Conventional spray application is prohibited.

NO _X TSD

Comment: TCEQ stated their support for the proposed approval. TCEQ requested the following changes: (1) on page 11, remove the incorrect reference to SCR, (2) on page 14, remove the incorrect reference to SNCR, (3) the correct ratings are less than 1 MW; 1.0 MW or greater, but less than 10MW; and 10 MW or greater. TCEQ also requested correcting minor discrepancies in the VOC TSD table of states' RACT comparisons.

Response: The EPA has provided final NO _X and VOC TSDs that reflect these corrections to the supplemental TSDs and the corrected TSDs are available in the docket.

F. Other Comments

The EPA received several comments that were not relevant to this action and/or which were outside the scope of this action. Consistent with CAA section 110, a SIP is designed to address the relevant NAAQS pollutant and its precursors. For ozone nonattainment purposes, the EPA is required to review the State's SIP revision to determine if it meets the RACT requirements of the CAA. RACT requirements for the ozone NAAQS apply to NO _X and VOC, which are ozone precursors.

Comment: Commenters claim that the EPA's review does not adequately address the potential for increased carbon dioxide (CO ₂ ) and other greenhouse gas (GHG) emissions, the Texas analysis provided does not appear to include an evaluation of the potential GHG impacts, and an overall environmental impact must also consider the economic costs associated with increased CO ₂ emissions. Commenters request that the EPA include an analysis of CO ₂ emissions changes associated with the proposed RACT determinations, and the environmental impacts of carbon pollution.

Response: Emissions and impacts associated with CO ₂ and other GHG emissions are outside of the scope of this action.

Comment: Commenters recommend if an area does not meet Federal standards then any and all industry in the State that does not meet air quality standard emissions be immediately shut down until air quality standards are met and sustained for one quarter. The commenters also recommended the implementation of a mandatory prison sentence for repeat polluters.

Response: Cessation of operation of industrial sources, enforcement, and penalties are outside the scope of this action.

Comment: Commenter stated their support for the approval and implementation of the proposed regulation to protect the environment and reduce pollution.

Response: The EPA appreciates the support.

III. Final Action

The EPA is approving the SIP revisions submitted by Texas on May 12, 2020, and May 13, 2020, that fulfill the Serious RACT requirements for the DFW nonattainment area for the 2008 ozone NAAQS. The EPA is also approving the concurrent 30 TAC Chapters 115 and 117 rule revisions. Specifically, the EPA is approving amendments to 30 TAC Chapter 115, Control of Air Pollution from Volatile Organic Compounds, §§ 115.10, 115.111, 115.112, 115.119, and 115.421, and 30 TAC Chapter 117, Control of Air Pollution from Nitrogen Compounds, §§ 117.10, 117.403, 117.8000, and 117.9030, into the Texas SIP. The 30 TAC Chapter 115 and 117 amendments implement major source NO _X and VOC RACT requirements to the DFW nonattainment area for the 2008 8-hour ozone NAAQS Serious classification.

We are also approving in this action the CTG VOC RACT negative declarations for the following categories of sources: fiberglass boat manufacturing materials, surface coating for flat wood paneling, letterpress printing, shipbuilding and ship repair surface coating operations, vegetable oil manufacturing, rubber tire manufacturing categories; for Wise County only: graphic arts-rotogravure and flexography, flexible package printing, refinery vacuum producing systems and process unit turnarounds, wood furniture manufacturing, and manufacture of synthesized pharmaceutical products.

IV. Incorporation by Reference

In this rule, the EPA is finalizing regulatory text that includes incorporation by reference. In accordance with requirements of 1 CFR 51.5, the EPA is finalizing the incorporation by reference the revisions to the Texas 30 TAC Chapters 115 and 117 regulations as described in Section III of this preamble, Final Action. The EPA has made, and will continue to make, these materials generally available through www.regulations.gov (please contact the person identified in the FOR FURTHER INFORMATION CONTACT section of this preamble for more information). Therefore, these materials have been approved by the EPA for inclusion in the SIP, have been incorporated by reference by the EPA into that plan, are fully federally enforceable under sections 110 and 113 of the CAA as of the effective date of the final rulemaking of the EPA's approval, and will be incorporated by reference in the next update to the SIP compilation.

V. Statutory and Executive Order Reviews

Under the Clean Air Act, the Administrator is required to approve a SIP submission that complies with the provisions of the Act and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, the EPA's role is to approve state choices, provided that they meet the criteria of the Clean Air Act. 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 Orders 12866 (58 FR 51735, October 4, 1993);
• Is not subject to Executive Order 14192 (90 FR 9065, February 6, 2025) because State Implementation Plan approvals under the CAA 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 Clean Air Act.

In addition, the SIP is not approved to apply on any Indian reservation land or in any other area where the EPA or an Indian Tribe has demonstrated that a Tribe has jurisdiction. In those areas of Indian country, the final 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).

This action is subject to the Congressional Review Act, and the EPA will submit a rule report to each House of the Congress and to the Comptroller General of the United States. This action is not a "major rule" as defined by 5 U.S.C. 804(2).

Under section 307(b)(1) of the Clean Air Act, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by May 22, 2026. Filing a petition for reconsideration by the Administrator of this final rule does not affect the finality of this action for the purposes of judicial review nor does it extend the time within which a petition for judicial review may be filed and shall not postpone the effectiveness of such rule or action. This action may not be challenged later in proceedings to enforce its requirements. (See section 307(b)(2).)

For the reasons stated in the preamble, the EPA amends 40 CFR part 52 as follows:

PART 52-APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

Subpart SS-Texas

[FR Doc. 2026-05607 Filed 3-20-26; 8:45 am]

BILLING CODE 6560-50-P

⁽¹⁾  90 FR 34812 (July 24, 2025).

⁽²⁾  90 FR 42885 (September 5, 2025).

⁽³⁾  Sources emitting VOCs in a quantity greater than the Serious area major source definition (50 tpy) and not covered by a CTG category or previously approved RACT rule.

⁽⁴⁾  The EPA's approval of the revisions to the Texas SIP concerning RACT requirements for sources covered by the 2016 Oil and Natural Gas Control Techniques Guidelines (CTG) for the DFW and HGB. nonattainment areas under the 2008 ozone NAAQS. See 88 FR 55379 (August 15, 2023).

⁽⁵⁾ https://www.epa.gov/catc/ractbactlaer-clearinghouse-rblc-basic-information.

⁽⁶⁾  See "par-1135---dsr---final", available in the docket.

⁽⁷⁾ Id.

⁽⁸⁾  Memorandum from Roger Strelow, EPA Assistant Administrator "Guidance for Determining Acceptability of SIP Regulations in Non-attainment Areas", December 9, 1976.

⁽⁹⁾  See "SCAQMD Rule 1146 development" available in the docket.

⁽¹⁰⁾ Id.

⁽¹¹⁾ Id., at page 2-6

⁽¹²⁾  See "par-1134---pdsr---;final", available in the docket.

⁽¹³⁾ Id.

⁽¹⁴⁾  See 32 TexReg 3206 (June 8, 2007), available in the docket.

⁽¹⁵⁾  See 40 TexReg 3695 (June 19, 2015), available in the docket.

⁽¹⁶⁾  See 40 TexReg 3695 (June 19, 2015), available in the docket.

⁽¹⁷⁾ See e.g., EPA's proposed approval notices for areas in Arizona (91 FR 6557 (February 12, 2026)), Ohio (90 FR 41925 (August 28, 2025)), and Colorado (90 FR 25960 (June 18, 2025)).

⁽¹⁸⁾ See Office of the Federal Register, "Document Drafting Handbook," page 2-8 (Aug. 2018 ed.), available at https://www.archives.gov/files/federal-register/write/handbook/ddh.pdf.

⁽¹⁹⁾ Id.