1 

# Control of Air Pollution from Nitrogen Compounds

Technical Support Document

for the EPA’s

Proposed Action on the Texas Chapter 117 Rules State Implementation Plan (July 2015)

December 10, 20152 For information in this technical support document, please contact:

James E. Grady Air State Implementation Section U.S. Environmental Protection Agency- Region 6

1445 Ross Avenue Dallas, Texas 75202-2733 (214) 665-6745 grady.james@epa.gov3 

## Table of Contents

SUBCHAPTER A, DEFINITIONS ..................................................................................................... .... 5

Section 117.10, Definitions ................................................................................................... ....................... 5

SUBCHAPTER B, COMBUSTION CONTROL AT MAJOR INDUSTRIAL, COMMERCIAL,

AND INSTITUTIONAL SOURCES IN OZON E NONATTAINMENT AREAS, DIVISION
2, DALLAS-FORTWORTH OZONE NONATTAI NMENT AREA MAJOR SOURCES ......... 7

DIVISION 4, DALLAS-FORT WORTH EI GHT-HOUR OZONE NONATTAINMENT AREA MAJOR SOURCES ............................................................................................................ ............. 7

Section 117.400, Applicability ................................................................................................ ..................... 7

Section 117.403, Exemptions ................................................................................................... ................... 8

Section 117.405, Emission Specifications for Reas onably Available Control Technology (RACT) . 9

Section 117.410, Emission Specifications for Eight-Hour Attainment Demonstration .................. 13

Section 117.423, Source Cap ................................................................................................... .................. 14

Section 117.425, Alternative Case Specific Specifications ..................................................................... 15

Section 117.430, Operating Requirements ....................................................................................... ....... 15

Section 117.435, Initial Demonstration of Compliance .... .................................................................... 1 6

Section 117.440, Continuous Demonstration of Compliance .............................................................. 16

Section 117.445, Notification, Recordkeeping, and Reporting Requirements ................................... 17

Section 117.450, Initial Control Plan Procedures .............................................................................. ..... 18

Section 117.452, Final Control Plan Procedures for Reasonably Available Control Technology .. 19

Section 117.454, Final Control Plan Procedures for Attainment Demonstration Emission Specifications ................................................................................................................ ............................... 20

Section 117.456, Revision of Final Control Plan ............................................................................... ..... 20

SUBCHAPTER C, COMBUSTION CONTROL AT MAJOR UTILITY ELECTRIC

GENERATION SOURCES IN OZONE NO NATTAINMENT AREAS, DIVISION 2,

DALLAS-FORT WORTH OZONE NONATTAINMENT AREA UTILITY ELECTRIC

GENERATION SOURCES ............................................................................................................ ........ 20

DIVISION 4, DALLAS-FORT WORTH EI GHT-HOUR OZONE NONATTAINMENT

AREA UTILITY ELECTRIC GENERATION SOURCES . ............................................................. 21

Section 117.1303, Exemptions .................................................................................................. ................ 21

Section 117.1310, Emission Specifications for Eight- Hour Attainment Demonstration ................ 22

Section 117.1325, Alternative Case Specific Specifications .................................................................. 2 2

Section 117.1335, Initial Demonstration of Compliance ...................................................................... 23

Section 117.1340, Continuous Demonstration of Compliance ............................................................ 23

Section 117.1345, Notification, Recordkeeping, and Reporting Requirements ................................. 244 Section 117.1350, Initial Control Plan Procedures ............................................................................. .... 24

Section 117.1354, Final Control Plan Procedur es for Attainment Demonstration Emission Specifications ................................................................................................................ ............................... 24

SUBCHAPTER G, GENERAL MONITO RING AND TESTING REQUIREMENTS, DIVISION 1, COMPLIANCE STACK TESTING AND REPORT REQUIREMENTS .......... 24

Section 117.8000, Stack Testing Requirements .............

..................................................................... .... 25

SUBCHAPTER H, ADMINISTRATIVE PROVISIONS, DIVISION 1, COMPLIANCE

SCHEDULES ..................................................................................................................... ......................... 25

Section 117.9010, Compliance Schedule for Dallas -Fort Worth Ozone Nonattainment Area Major

Sources ....................................................................................................................... ................................... 25

Section 117.9030, Compliance Schedule for Dallas-Fort Worth Eight-Hour Ozone Nonattainment Area Major Sources .............................................................................................. ........... 26

Section 117.9110, Compliance Schedule for Dalla s-Fort Worth Ozone Nonattainment Area Utility Electric Generation Sources ........................................................................................... ............... 27

Section 117.9130, Compliance Schedule for Dallas-Fort Worth Eight-Hour Ozone Nonattainment Area Utility Electric Generation Sources ..................................................................... 27

DIVISION 2, COMPLIANCE FLEXIBILITY .................................................................................... 28

Section 117.9800, Use of Emission Credits for Complianc e ................................................................ 28

Section 117.9810, Use of Emission Reductions Generated from the Texas Emissions Reduction Plan (TERP) ................................................................................................................... .............................. 285 

### SUBCHAPTER A, DEFINITIONS

Section 117.10, Definitions

The proposed revision recommends revising the definitions of applicable ozone nonattainment

areas in § 117.10(2). The submitted revision proposes repeal of existing § 117.10(2)(B), DFW ozone nonattainment area. The existing definition of DFW ozone nonattainment area includes Collin, Dallas, Denton, and Tarrant Counties. Divisions rela ting to this four-county DFW area have been made obsolete by the passing of compliance dates , and sources of NOX previously subject to these divisions are now required to comply with more stri ngent rules in existing divisions relating to the expanded nine-county DFW area. The submi tted revision proposes re-lettering existing § 117.10(2)(C), DFW eight-hour ozone nonattainment area, to § 117.10(2)(B), and existing § 117.10(2)(D), Houston-Galveston-Braz oria ozone nonattainment area, to § 117.10(2)(C). The submitted revision also proposes to revise the definition of DFW eight-hour ozone nonattainment area. The existing definition of DFW eight-hour ozone nonattainment area includes Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwa ll, and Tarrant Counties. For the purposes of Chapter 117, Subchapter D, Combustion Control at Minor Sources in Ozone Nonattainment Areas, the proposed revised definition includes Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, and Tarrant Counties, and for all other divisions of Chapter 117, the proposed revised definition includes Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker , Rockwall, Tarrant, and Wise Counties. This proposed change to the de finition of DFW eight-ho ur ozone nonattainment area is necessary because the submitted revision is not proposing to apply the existing minor source rules to sources located in Wise County.

The submitted revision proposes changing the definition of electric power generating system in § 117.10(14), to clarify its applicability to indepe ndent power producers in the ozone nonattainment areas. Systems that are owned or operated by in dependent power producers and are located in the

Beaumont-Port Arthur ozone nonattainment area or the 10-county DFW 2008 eight-hour ozone nonattainment area are subject to Chapter 117, Subc hapter C. However, as the current definition in existing § 117.10(14)(C) states, cogeneration units and independent power producers in the HoustonGalveston-Brazoria ozone nonattainment area are subject to the industrial, commercial, and institutional rules in Subchapter B.

The submitted revision therefore proposes revising § 117.10(14) to clarify this difference in applicability between the different ozone nonattain ment areas for independent power producers. The proposed revisions to subparagraph (A) would add independent power producers but limit the applicability of the definition to only the Beaumo nt-Port Arthur and DFW areas. Proposed changes

to § 117.10(14)(A) include removal of existing § 117.10(14)(A)(ii), DFW, consistent with the proposed removal of § 117.10(2)(B). The submitted revision proposes re-numbering existing § 117.10(14)(A)(iii), DFW eight-hour, to § 117.10(14)(A)(ii). Existing § 117.10(14)(A)(iv), HoustonGalveston-Brazoria, is proposed for removal to coincide with changes proposed in § 117.10(14)(B) and proposed revised § 117.10(14)(C). The submitted revision also proposes to remove existing § 117.10(14)(B) and move it to amended § 117.10(14)(D). To address electric power generating systems located in the Houston-Galveston-Brazor ia ozone nonattainment area subject to Chapter 117, Subchapter C, The submitted revision proposes a modified paragraph (B) in § 117.10(14). Proposed § 117.10(14)(B) is necessary to address specifi c combustion unit types that are part of electric power generating systems located in th e Houston-Galveston-Brazoria ozone nonattainment6 area that are subject to Subchap ter C, Division 3 while maintaining the distinction established under § 117.10(14)(C) for independent power producers. The submitted revision also proposes revising § 117.10(14)(C) to clarify that the provision only a pplies to Subchapter B, Division 3 and to update the reference from proposed revised § 117.10(14)(A) to concurrent proposed § 117.10(14)(B). These changes to § 117.10(14) are proposed to clarify the existing definition of an electric power generating system and are not intended to expand the definition.

The submitted revision proposes revising the definition of emergency situation in § 117.10(15)(A)(ii) and (vii) to update the refere nces to the Electric Reliability Council of Texas (ERCOT) Protocols to the most recent publishe d version of the ERCOT Protocols, August 13,

2014.

The submitted revision proposes revising the definition of large utility system in § 117.10(24) to

remove the reference to DFW ozone nonattainment area as an applic able ozone nonattainment area

to be consistent with the proposed removal of existing § 117.10(2)(B).

The submitted revision proposes revising the definition of major source in § 117.10(29). Proposed changes to § 117.10(29)(B) include the removal of refe rences to DFW and DFW eight-hour ozone nonattainment area and adding Collin, Dallas, De nton, Ellis, Johnson, Kaufman, Parker, Rockwall, and Tarrant Counties as applicable counties. Proposed § 117.10(29)(C) includes a new major source applicability threshold of at least 100 tpy of NOX for sources located in Wise County. These changes are necessary to be consistent with proposed § 117.10(2)(B), concerning the proposed revised definition of DFW eight-hour ozone nonattain ment area and to reflect the difference in the applicability threshold because of the different cl assifications between Wise County and the othernine counties included in the ozone nonattainment area. The submitted revision also proposes to reletter existing § 117.10(29)(C) to § 117.10(29)(D) and re-letter existing § 117.10(29)(D) to § 117.10(29)(E).

Proposed revisions to the definition of small utility system in § 117.10(44) include the removal of

the reference to DFW ozone nonatta inment area as an applicable ozone nonattainment area to be consistent with the proposed removal of existing § 117.10(2)(B), DFW ozone nonattainment area. The submitted revision proposes revisions to the definition of unit in § 117.10(51).

Proposed changes to § 117.10(51)(A) include a reference to proposed new § 117.405, Emission Specifications for Reasonably Available Control Technology (RACT), to define unit as any boiler, process heater, stationary gas turbine, or stat ionary internal combustion engine, as defined in § 117.10. In addition, proposed revised § 117.10(51)(A) includes removing references to sections proposed for repeal.

Finally, proposed changes to § 117.10(51)(B) include deleting references to § 117.210 and § 117.1110 because these sections are proposed for repeal.

Evaluation: The proposed definitions will clarify applicability of NO X rules and assist in compliance determination for Wise County and the remaining ni ne Counties in the DFW area. Defining “unit” specifically will assist in RACT determinations for individual sources. The EPA is proposing approval of all updated definitions to § 117.10 of the Texas SIP.7 

### SUBCHAPTER B, COMBUSTION CONTROL AT MAJOR INDUSTRIAL, COMMERCIAL, AND INSTITUTIONAL SOURCES IN OZONE NONATTAINMENT AREAS, DIVISION 2, DALLAS-FORTWORTH OZONE NONATTAINMENT AREA MAJOR SOURCES

The submitted revision proposes repeal of existing Subchapter B, Division 2, DFW which has been made obsolete by the passing of compliance date s because sources of NOX previously subject to this division are now required to comply with mo re stringent rules in existing Subchapter B,

Division 4.



### DIVISION 4, DALLAS-FORT WORTH EIGHT-HOUR OZONE NONATTAINMENT AREA MAJOR SOURCES

To address new RACT requirements for sources of NOX located in Wise County, The submitted revision is proposing a new section, § 117.405, in proposed revised Subchapter B, Division 4 that would include new rules applicable to any major stationary source of NOX in Wise County. New NOX RACT requirements necessary for major stat ionary sources of NOX in the other nine counties that are not already addressed under the cu rrent rules are included as proposed revisions to the existing § 117.410. The submitted revision is not proposing to expand the list of applicable unit types at major ICI stationary sources of NOX as it currently exists in § 117.400 in the proposed revised Subchapter B, Division 4.

Section 117.400, Applicability Proposed revisions to § 117.400 clarify which unit types locate d in specific counties in the proposed revised DFW eight-hour ozone nonattainment area would be subject to the proposed revisions of Subchapter B, Division 4. Proposed § 117.400(a) retains the list of applicable units located at major sources of NOX in existing § 117.400 and specifies that these units must be located at major sources of NOX located in Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, or Tarrant County. This change is necessary to clarify that specific units located in the existing nine-county DFW eight-hour ozone nonattainment ar ea would be subject to proposed § 117.410(a), with the exception of the one wood-fired boiler located in Kaufman County. The wood-fired boiler identified in Kaufman County in the calendar year 2012 TCEQ Point Source Emissions Inventory (2012 EI) would be an applicable unit under proposed § 117.400(a) subject to the NOX emission specification of proposed new § 117.405(a) as an ICI boiler.

The submitted revision proposes § 117.400(b) to specify the units located at major sources of NOX located in Wise County that would be subject to proposed § 117.405(b). The proposed stationary source type categories are ICI process heaters, st ationary gas turbines, and stationary internal combustion engines.

Evaluation: The EPA will review RACT action in a future rulemaking action. However, the proposed revisions ensure that RACT is applicable to major stationary sources of NO X in nine

Counties within the DFW area. This is consisten t with section 182(b) of the CAA. The EPA is proposing approval of all revisions to § 117.400 of the Texas SIP.8 Section 117.403, Exemptions Proposed revisions to § 117.403 clarify exemption criteria of units that would be exempt from specified requirements of proposed revised Subchap ter B, Division 4. To be consistent with the proposed revisions in § 117.400, the submitted revision proposes to revise § 117.403(a), which retains the list of applicable unit types, sizes, and uses in existing § 117.403(a). The submitted revision proposes to specifically list Collin, Dallas, Denton , Ellis, Johnson, Kaufman, Parker, Rockwall, or Tarrant County in subsection (a) to make clear that the list of exemptions provided in the subsection is only applicable in those counties and because exemptions applicable in Wise County are proposed to be listed separately. Changes to existing § 117.403(a)(4) are proposed to facilitate consistency between the unit size exemption threshold in § 117.403(a)(4) and the existing definition of maximum-rated capacity, as defined in § 117.10. Proposed revisions to § 117.403(a)(7)(A) and (B) are necessary to clarify that the exemption criteria fo r research and testing and performance verification and testing refer to research, testing, and performance verification of the stationary gas turbine or stationary internal combustion engine itself. Revisions to § 117.403(a)(7)(D) are proposed in order to clarify that unit operation for testing or maintenan ce purposes up to 100 hours per year refers to testing and maintenance of the stationary gas turbin e or stationary internal combustion engine itself. In addition, the submitted revision proposes revising the operating hours limit for exemption criteria for stationary gas turbines and stationary internal combustion engines from a rolling 12-month average to a rolling 12-month basis. The owner or operator of an affected unit would sum all operating hours for a consecutive 12-month period , and continue doing so on a rolling 12-month basis, as opposed to calculating the average of all operating hours during a consecutive 12-month period. A 12-month rolling average would only apply to an hours per month limit, thus conflict with an hour per year limit while a 12-m onth rolling basis is the preceding 12-month total, which matches the 100 hours per year limit. This would more accu rately reflect the intent of the rule and how an affected unit would demonstrate compliance with the operating restriction of a total of 100 hours

per year.

Similarly to more accurately reflect the intent of the rule, revisions to existing § 117.403(a)(8)(A) and (9)(A) are proposed by The submitted revision to specify that the operating hours limit for exemption criteria for stationary diesel engine s would be on a rolling 12-month basis and not on a rolling 12-month average and thus how an affected unit would demonstra te compliance with the operating restriction of a total of 100 hours per year. The owner or operator of an affected unit would sum all operating hours for a consecutive 12-month period, and continue doing so on a rolling 12-month basis, as opposed to calculating the average of all operating hours during a consecutive 12-month period.

The submitted revision propos es to delete existing § 117.403(b), concerning increment of progress (IOP) exemptions, because the provisions reference existing § 117.410(a), which is concurrently proposed for deletion by the submitted revision. The provisions of proposed deletion of § 117.403(b) apply to gas-fired stationary, reciprocating internal combustion engines which, due to the passing of compliance dates, are now subject to mo re stringent rules in existing Subchapter B,

Division 4.

Proposed § 117.403(b) specifies the unit types, sizes, or uses for units located in Wise County that would be exempt from the requirements of this division. Units for which the unit type, maximumrated capacity, or specific use would be technically or economically infeasible to comply with the9 proposed NOX emission specifications are exempted fr om the provisions of this division, except as specified in proposed revised §§ 117.440(i), 117.445(f)(4), an d 117.450 and in proposed new § 117.452. The exceptions to the proposed exemptions are related to monitoring, recordkeeping, and control plan requirements associated with exempted units. Proposed amended § 117.403(b)(1) specifies that ICI process heaters with a maximum-rated capacity of less than 40 million British thermal units per hour (MMBtu/hr) would be exemp ted. This exemption level is proposed to be consistent with previous RACT exemption approach es for ICI process heaters located in the DFW

area and the Houston-Galveston-Braz oria ozone nonattainment area.

The following stationary gas turbines and stati onary internal combustion en gines would be exempt in proposed § 117.403(b)(2)(A) - (E): gas turbines and engines used in research and testing of the unit, used for purposes of performance verificati on and testing of the unit, used solely to power other gas turbines or engines during startups; used exclusively in emergency situations (except that operation for testing or maintenance purposes of the ga s turbine or engine itself is allowed up to 100 hours per year, based on a rolling 12-month basis); or used in response to and during the existence of any officially declared disaster or state of emergency. These exemptions are proposed due to the limited number, if any, of these unit types used in this dedicated service.

Proposed § 117.403(b)(3) specifies an exemption for any stationary diesel engine, and proposed § 117.403(b)(4) specifies an exemption for any stationary dual-fuel engine. Both stationary diesel and dual-fuel engines would meet the applicability criter ion of stationary internal combustion engine in proposed § 117.400(b); however, no units of these types were identified in the 2012 EI for Wise County, and The submitted revision is not proposin g emission specifications for these unit types. Proposed § 117.403(b)(5) specifies an exemption for stat ionary gas-fired engines with a horsepower (hp) rating of less than 50 hp. This is consis tent with the size exemption threshold currently provided for stationary gas-fired engines in the other nine counties of the nonattainment area previously established as a reasonable threshold to exempt smaller engines from the NOX control requirements.

Finally, The submitted revision proposes subsection (c) to contain new section cross-references to proposed § 117.410(a)(1) and (c) and amendments to the cross-references to existing § 117.410(b)(1) and (d).

Evaluation: The proposed revisions state what unit s or type of units will be exempt as major NO X sources, and not subject to 182(b) of the CAA. Iden tification of sources not subject to the rule will assist in compliance determinations. The EPA is proposing approval of all revisions to § 117.403 of

the Texas SIP.

Section 117.405, Emission Specifications for Reasonably Available Control Technology (RACT) The submitted revision proposes new § 117.405, which establishes proposed NOX emission specifications to satisfy RACT requirements for units in the 10-county DFW 2008 eight-hour ozone

nonattainment area that would be subject to this rulemaking.

Proposed new § 117.405(a) includes the proposed new emission specification for wood-fired boilers located in the proposed revised DFW eight-hour ozone nonattainment area. The proposed 0.1210 pounds per million British thermal units (lb/MMBtu) emission specification for wood fuel-fired boilers is based on the permitted Best Available Cont rol Technology limit for the unit identified in the 2012 EI, and it is anticipated to require owners or operators of affected units to possibly install and operate selective catalytic reduction (SCR). Th e unit identified in Kaufman County in the 2012 EI currently operates with SCR for NOX contro l and uses a continuous emissions monitoring system (CEMS) for monitoring NOX emissions. While the submitted revision is proposing this emission standard satisfies RACT for this particul ar wood fuel-fired boiler because the facility has already installed the controls necessary to meet the requirement, the submitted revision is not proposing that SCR represents RACT on w ood fuel-fired boilers in general.

Proposed new § 117.405(b) includes the proposed new emi ssion specifications that would apply to the following unit types at major ICI stationary sources of NOX located in Wise County: ICI process heaters; stationary, reciprocating internal combustion engines; and stationary gas turbines. Proposed new § 117.405(b)(1) would establish the NOX emission specifications of 0.10 lb/MMBtu (or alternatively, 82 parts per million by volume (ppmv), at 3.0% oxygen (O2), dry basis) for process heaters with a maximum-rated capacity equal to or greater than 40 MMBtu/hr. Combustion modifications such as dry low-NOX combustors ma y be necessary for process heaters with a maximum-rated capacity equal to or greater than 40MMBtu/hr to comply with the proposed 0.10 lb/MMBtu emission specification. No liquid-fired pr ocess heaters were identified in the 2012 EI in Wise County; however, combustion modifications may be necessary for a liquid-fired process heater to comply with the proposed NOX emission specifications in proposed new § 117.405(b)(1).

Proposed new § 117.405(b)(2) provides NOX emission speci fications for stationary, reciprocating internal combustion engines. The proposed language in § 117.405(b)(2)(A) and (B) would establish NOX emission specifications for stationary, gas-fire d rich-burn and lean-burn, reciprocating internal combustion engines. Gas-fired, rich-burn engine s would be limited to 0.50 grams per horsepowerhour (g/hp-hr) in proposed new § 117.405(b)(2)(A). The proposed emission specifications for some gas-fired, lean-burn engines in § 117.405(b)(2)(B) would be based on specific engine process parameters and the date the engine was placed into service, modi fied, reconstructed, or relocated. Any White Superior, model 8GTL825, gas-fired, le an-burn four-cycle engines placed into service, modified, reconstructed, or relocated before June 1, 2015 would be limited to 12.0 g/hp-hr, and on or after June 1, 2015 would be limited to 2.0 g/hp-hr. Any Clark, model HBAGT or HBA-6, gasfired, lean-burn two-cycle engines placed into serv ice, modified, reconstructed, or relocated before June 1, 2015 would be limited to 12.0 g/hp-hr, and on or after June 1, 2015 would be limited to 2.0 g/hp-hr. Finally, any Fairbanks Morse, model ME P-8T, gas-fired, lean-burn two-cycle engines placed into service, modified, reconstructed, or relocated before June 1, 2015 would be limited to 4.0 g/hp-hr, and on or after June 1, 2015 would be limi ted to 2.0 g/hp-hr. All other gas-fired, lean-burn engines would be limited to 2.0 g/hp-hr.

Nonselective catalytic reduction (NSCR), with an air- to-fuel ratio (AFR) controller, is expected to be the primary control technology for gas-fired, rich-b urn engines. In some ca ses, the addition of a secondary catalyst module may be required to meet the proposed emission specification. The submitted revision proposes the 0.50 g/hp-hr emissi on specification represents RACT for gas-fired, rich-burn engines based on the low cost and wide-s pread demonstrated effectiveness of NSCR with meeting this control level.11 The proposed revision provides specific NOX em ission specifications based on engine make and model for the White Superior, Clark, and MEP unit s due to the following: engine manufacturers today produce few, if any, of these engine makes and models; retrofit options or kits to reduce NOX emissions may not exist for some of these particular makes and models; some units may have already undergone combustion modifications, such as low-emission combustion technology, to reduce emissions and thus may be unable to further reduce NOX emissions; and in some cases the cost to retrofit the unit may be more than the cost of a new unit.

The proposed revision therefore requires that these proposed emission levels for these specific units would satisfy RACT requirements considering technol ogical and economic feasibility. For all other lean-burn engines, the submitted revision anticipates that affected units would require combustion modifications to comply with the proposed 2.0 g/hp-hr emission specification, if necessary. Any new gas-fired, lean-burn engines installed in Wise County should be able to meet the proposed 2.0 g/hp-hr standard without modification or installation of additional controls.

The submitted revision acknowledges that the curre nt emission specifications for stationary gasfired, lean-burn engines in the other nine counti es of the DFW eight-hour ozone nonattainment area are between 0.50 and 0.70 g/hp- hr, and are more stringent than the emission specifications proposed for Wise County. However, the submitted revi sion does not consider this control level to represent RACT for the gas-fired, lean-burn engines in Wise County. In proposing the emission specifications for gas-fired, lean-burn engines in the nine-county DFW 1997 eight-hour ozone nonattainment area in December 2006, the submitted revision acknowledged that meeting this control level may necessitate the installation of SCR technology (31 TexReg 10599, December 29, 2006). 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, leanburn engines in Wise County. The submitted revi sion's adoption of the emission specifications for gas-fired, lean-burn engines in the nine-cou nty DFW1997 eight-hour ozone nonattainment area represented an appropriate control measure to help the area reach attainment with the 1997 eighthour ozone NAAQS. However, control measures nece ssary to reach attainment can, and may, go beyond RACT requirements. Some of the NOX c ontrol requirements adopted in 2007 for the DFW 1997 ozone NAAQS attainment demonstration were based only on RACT level of control and some, such as the emission specifications for gas-fired lean-burn engines, were beyond RACT. While the submitted revision did not make this distinction in adopting the 2007 rulemaking and only indicated that the NOX emission specifications wo uld fulfill RACT, the distinction is necessary in

order to make clear the submitted revision's inten t for RACT in Wise County. Additionally, the submitted revision allows for source-specific RACT determinations, as the definition of RACT states. The submitted revision provides that the NOX emission specification in proposed § 117.405(b)(2)(B) present RACT for the particular gas-fired lean-burn engines in Wise County.

The proposed revision provides for a new § 117.405(b)(3) for NOX emission specifications for stationary gas turbines in Wise Cou nty. Stationary gas turbines with a hp rating of less than 4,500 hp would be limited to 0.45 lb/MMBtu; stationary gas turbines with a hp rating of 4,500 hp or greater, but less than 10,000 hp, would be limited to 0.20 lb/MMBtu; and stationary gas turbines with a hp rating of 10,000 hp or greater would be limited to 0.15 lb/MMBtu. These limits for industrial gas

turbines are based on information identified in th e 2012 EI similar to the approach used for gasfired lean-burn engines: retrofit options or kits to reduce NOX emissions may not exist for some of these particular makes and models; some units ha ve already been retrofitted with dry low-NOX12 combustors to reduce emissions and thus may be unable to further reduce NOX emissions; and in some cases the cost to retrofit the unit may be more than the cost of a new unit. The submitted revision therefore proposes that these proposed emission levels for these specific units should satisfy RACT requirements considering technological and economic feasibility.

The proposed new § 117.405(c), concerning NOX averaging ti me, specifies the averaging times for compliance with the emission specifications of proposed new § 117.405(a) and (b). Proposed new § 117.405(c)(1) specifies the averaging time for unit s equipped with CEMS or predictive emissions monitoring systems (PEMS) and provides three options under proposed subparagraphs (A) - (C). The proposed subparagraph (A) specifies a rolling 30-day average, in units of the applicable emission standard. Proposed subparagraph (B) specifies a block one-hour average basis, in the units of the applicable emission standard. Proposed subparagra ph (C) specifies a block one-hour average, in pounds per hour, for boilers and process heaters, calculated based on the maximum-rated capacity and the applicable emission specification. For un its not equipped with CEMS or PEMS, proposed

new § 117.405(c)(2) requires the averaging time to be a block one-hour average in the units of the applicable emission standard but allows the emissi on specifications for boilers and process heaters to be applied in pounds per hour as specified in proposed new § 117.405(c)(1)(C).

The submitted revision proposes new § 117.405(d) that would establish emission specifications for related emissions from any unit subject to the emission specifications in proposed new § 117.405(a) or (b). This is necessary to ensure that the NOX reduction strategies of this proposed rulemaking do not result in a significant increase in emissions of other pollutants. Proposed new § 117.405(d)(1) establishes a carbon monoxide (CO) emission spec ification of 400 ppmv at 3.0% O2, dry basis (or alternatively, 3.0 g/hp-hr for stationary internal combustion engines; or 775 ppmv at 7.0% O2, dry basis for wood fuel-fired boilers or process heaters) on a rolling 24-hour averaging period for units equipped with CEMS or PEMS for CO, and on a block one-hour averaging period for units not equipped with CEMS or PE MS for CO. Proposed new § 117.405(d)(2) specifies that units that inject urea or ammonia into the exhaust stream for NOX control must meet a 10 ppmv ammonia emission specification. The 10 ppmv ammonia emi ssion specification is corrected to 3.0% O2, dry, for boilers and process heaters, 15% O2, dry, for stationary gas turbines and gas-fired lean-burn engines, and 3.0% O2, dry, for all other units. The specified averaging time for the ammonia emission specification is on a rolling 24-hour averag ing period for units equipped with CEMS or PEMS for ammonia, and on a block one-hour averag ing period for units not equipped with CEMS or PEMS for ammonia. The proposed new subsection (d)(3) specifies that the correction of CO emissions to 3.0% O2, dry basis, does not apply to boilers or process heaters operating at less than

10% of maximum load and with stack O2 more than 15%.

The proposed § 117.405(e) specifies conditions for compliance flexibility with the NOX emission specifications of proposed new § 117.405. The proposed § 117.405(e)(1) specifies that owners or operators may use the source cap option under proposed revised § 117.423, or emission reduction credits as specified in proposed revised § 117.9800 to comply with th e NOX emission specifications of proposed new § 117.405(a) or (b). Proposed new subs ection (e)(2) prohibits using proposed

revised § 117.425 as a method of compliance with the NOX emission specifications of proposed

new § 117.405(a) or (b). This prohibition is necessary to ensure that the NOX reductions anticipated from this proposed rulemaking would be realiz ed. The proposed subsection (e)(3) sp ecifies that13 owners or operators may petition the executive director for an alternative to the CO and ammonia emission specifications of proposed new § 117.405(d) according to proposed revised § 117.425.

The submitted revision proposes new § 117.405(f) to establish provisions for prohibition of circumvention to ensure that the anticipated NOX emission reductions associated with this proposed rulemaking would be realized. The pr oposed subsection (f)(1) establishes that the maximum-rated capacity used to determine the applicability of the emission specifications in proposed new § 117.405, the initial compliance demonstration in proposed revised § 117.435, the monitoring and testing requirements in proposed revised § 117.440, and the final control plan requirements in proposed new § 117.452, respectively, must be the greater of the maximum-rated capacity as of December 31, 2012, the maximum- rated capacity after December 31, 2012, or the maximum-rated capacity authorized by a permit issued under 30 TAC Chapter 116 after December 31, 2012. Proposed new § 117.405(f)(2) specifies that a unit's classification for the purposes of proposed revised new Subchapter B, Division 4, is determined by the most specific classification applicable to the unit as of December 31, 2012. Finally, proposed new § 117.405(f)(3) specifies that a

source that met the definition of a major source as of December 31, 20 12 is always classified as a major source for the purposes of proposed revised Subchapter B, Division 4. A source that did not meet the definition of major source on December 31 , 2012, but which at any time after December 31, 2012, becomes a major source, would from that time forward always be classified as a major source for purposes of proposed revised Subchapter B, Division 4.

Evaluation: Identification of major NO X sources subject to 182(b) of the CAA and 30 TAC Chapter 117 control requirements will assist in complianc e determinations. The EPA is proposing approval

of new § 117.405 of the Texas SIP. However, RACT applicability determinations will be handled in a different rulemaking action.

Section 117.410, Emission Specifications for Eight-Hour Atta inment Demonstration The submitted revision proposes amending existing § 117.410(a) and to move existing § 117.410(b), Emission specifications for eight-hour ozone attainment demonstration, to proposed § 117.410(a).

The submitted revision established the em ission specifications under existing § 117.410(a) for stationary, gas-fired rich-burn and lean-burn re ciprocating internal combustion engines with a maximum-rated capacity of 300 hp or greater under the 5% IOP plan for the nine counties in the existing DFW 1997 eight-hour ozone nonattainment ar ea. With the passing of the compliance date for eight-hour ozone attainment demonstration emission specifications in existing § 117.9030(b), these gas-fired engines are now subject to emissi on specifications for eight-hour ozone attainment demonstration in existing § 117.410(b). In addition, The submitted revision proposes to specifically list Collin, Dallas, Denton, Ellis, Johnson, Kaufma n, Parker, Rockwall, or Tarrant County in proposed subsection (a) to make clear that the emi ssion specifications provided in the subsection are only applicable in those counties and because emi ssion specifications applicable in Wise County are proposed to be listed separately. Because of the amendment to subsection (a), all other subsections are being re-lettered accordingly. The proposed revisions to existing § 117.410(b)(7)(A) include updating the reference in the figure to proposed § 117.410(a)(7)(A) to coincide with th e proposed incorporation of existing § 117.410(b) into proposed § 117.410(a).14 The proposed § 117.410(c) establishes NOX emission specifications for related emissions from any unit subject to the emission specifications in proposed § 117.410(a). The submitted revision proposes to delete existing subparagraph (A) of existing subsection (d)(4) to be concurrent with proposed the amendment of existing § 117.410(a) and also because the IOP standards for the nine counties in the existing DFW area are being amended. In addi tion, The submitted revision proposes to move the provisions in existing subparagraph (B) of existing subsection (d)(4) to proposed § 117.410(c)(4)(A) - (C) because the restructuring of paragr aph (4) is necessary to conform to Texas Register formatting requirements.

Proposed revisions to existing § 117.410(f)(5) include updating the reference from existing § 117.410(b)(14) to proposed § 117.410(a)(14) to coincide with the proposed incorporation of existing § 117.410(b) into proposed § 117.410(a). Lastly, The submitted revision proposes to delete existing § 117.410(f)(6) since stationary gas-fired en gines are no longer subject to existing § 117.410(a). These gas-fired engines are now subject to provisions in existing § 117.410(b), which is proposed to be moved to proposed § 117.410(a).

In § 117.410(f), The submitted revision proposes to cl arify that testing or maintenance associated with the operating restriction of any stationary dies el or dual-fuel engine for testing or maintenance

between the hours of 6:00 a.m. and noon refers to testing or maintenance of the engine itself.

Evaluation: This section contains NO X emission limitations that are more stringent than RACT and normally result in additional NO X reductions for achieving attainment under the 2008 eight-hour ozone NAAQS. This distinction and county deline ation will enhance the ov erall structure of the rule. The EPA is proposing approval of all revisions to § 117.410 of the Texas SIP.

Section 117.423, Source Cap The submitted revision proposes revisions to § 117.423(a) to incorporate references to proposed

new § 117.405, Emission Specifications for RACT. The source cap approach is an option provided to owners or operators of affected units for demonstrating compliance with the NOX emission specifications of proposed new § 117.405 in addition to those of proposed revised § 117.410. The proposed revised § 117.423(b) specifies the equations and procedures for determining the source cap allowable NOX mass emission rate. The equation in proposed revised § 117.423(b)(1) specifies how to calculate the 30-day rolling average emission cap in pounds per day. The proposed

revision of § 117.423(b)(1) would contain new secti on cross-references to proposed new § 117.405. Proposed revised subsection(b)(1) would also define the averaging period for determining the historical average daily heat input, variable Hi , as the 24 consecutive months between January 1, 2012 and December 31, 2013 for units subject to proposed new § 117.405. In addition, the effective date for an applicable permit emission limit for clause (ii) of variable Ri for units subject to proposed

new § 117.405 is December 31, 2012. The submitted revision proposes the new date and date range to make clear the dates that would apply to units subject to proposed new § 117.405 and the existing date and date range in existing subsection (b)(1) that apply to units subject to § 117.410.

The proposed revision of § 117.423(b)(4) contains an update to the equation for calculating the source cap allowable emission rate, in pounds per hour, for stationary internal combustion engines. The submitted revision proposes to revise the expone ntial power in the equation from a positive to a negative number. This change would allow the units, Btu and MMBtu, of the equation to properly15 cancel. Without this proposed change, the equation would calculate a value that would misrepresent the cap that is intended by the existing rule.

The proposed revision of § 117.423(b)(5) specifies the equations for calculating the source cap allowable emission rate, in pounds per hour, for stationary gas turbines. The submitted revision proposes to delete the section cr oss-reference to existing § 117.410(b) in the equation and to add new section cross-references to proposed new § 117.405 and proposed revised § 117.410 to reflect changes proposed in those sections.

The proposed revision of § 117.423(g) includes section cross-references to proposed new § 117.405 for conditions for including a permanently retired, decommissioned, or rendered inoperable unit in the source cap. Proposed revised subsection (g)(1) sp ecifies that the shutdown must have occurred after December 31, 2012, for un its subject to proposed new § 117.405. In addition for units subject to proposed new § 117.405, if the unit was not in service 24 consecutive months between January 1, 2012 and December 31, 2013, proposed revised subsection (g)(3) specifies the actual heat input must be the average daily heat input for the continuous time period that the unit was in service, consistent with the heat input used to represent the unit's emissions in the 2012 modeling inventory. The submitted revision proposes the new date and date rang e to make clear the dates that would apply to units subject to proposed new § 117.405 and the existing date and date range in existing subsection (g) that apply to units subject to § 117.410. The years used for the rule represent the year associated with the level of activity of the units participating in the cap and the baseline that is established for modeling emissions at the time the regulations are developed. The cap is then based on that year.

Evaluation: Source cap will provide for operationa l flexibility to the source to meet the required

NO X control requirements. The equations in Section 117.423, provide the units of emission, duration, rates, and allowable emission limits assigned to each type of affected source in 30 TAC Chapter 117. The EPA is proposing approval of all revisions to § 117.423 of the Texas SIP.

Section 117.425, Alternative Ca se Specific Specifications The submitted revision proposes to revise existing § 117.425(a), which provides procedures concerning alternative case specific specifications , by including new section cross-references to proposed new § 117.405(d) and a corrected reference to § 117.410(c). Proposed revisions to paragraph (2) include a section cross-reference to proposed new § 117.405.

Evaluation: The Alternative Case Specific Specifi cations provide operational flexibility while a source meet its applicable emission limitation. Th e EPA is proposing approval of all revisions to § 117.425 of the Texas SIP.

Section 117.430, Operating Requirements The submitted revision proposes revisions to existing § 117.430, which establishes operating requirements for sources subject to proposed revised Subchapter B, Division 4. Proposed revised subsection (b) adds a section cro ss-reference to proposed new § 117.405. Additional changes to proposed revised subsection (b) include deleting the reference to existing § 117.410(a) and (b) and a proposed reference to revised § 117.410.16 Evaluation: the revision will ensure cross-references within 117.430 are up to date. The EPA is proposing approval of all revisions to § 117.430 of the Texas SIP.

Section 117.435, Initial Demonstration of Compliance The submitted revision proposes revisions to existing § 117.435, which details the monitoring and testing procedures required to demonstrate co mpliance with the emission specifications of Subchapter B, Division 4. Proposed revised § 117.435(c) replaces the reference to " relative accuracy test

audit" (RATA) with the more general term, " monitor certification." This change clarifies that verification of operational status must include completion of the initial monitor certification, which includes not only the RATA but also th e seven-day drift test.

Evaluation: This section will establish the baseli ne plan and method by which an affected source intends to meet its applicable emission limitations revision. It will ensure monitoring data are accurate, replicable, and certified accordingly by requiring the initial monitor certification. The EPA is proposing approval of all revisions to § 117.435 of the Texas SIP.

Section 117.440, Continuous De monstration of Compliance Proposed revised § 117.440(a)(1), which details the list of units that would be subject to the fuel metering requirements of proposed revised § 117.440(a), adds a section cross-reference to proposed

new § 117.405, concerning emission specifications for RACT. The submitted revision is also clarifying that operation of the totalizing fuel flow meter in conjunction with the unit operating time is not time averaged over a calendar year but instead continuous operating time during a calendar year that is representative of the total fuel meter operating time. This total fuel meter operating time

must still be at least 95% of the time that the unit operates. In addition, The submitted revision proposes revised § 117.440(a)(1)(A) to provide an exemption for wood-fired boilers to the fuel flow metering requirements of existing subsection (a)(1). Instead of installing and operating a totalizing fuel flow meter, owners or operators of wood-f ired boilers in the 10-county DFW 2008 eight-hour

ozone nonattainment area would demonstrate co mpliance with the monitoring provisions of proposed revised Subchapter B, Division 4 through ei ther fuel use records that would be required in proposed revised § 117.445(f) or the alternative moni toring provision of existing § 117.440(a)(2)(A). As mentioned previously in this preamble, the one wood-fired boiler identified in Kaufman County currently operates with SCR and a NOX CEMS.

Provisions in existing subsection (c) specify the units for which owners and operators shall install and operate a CEMS or PEMS to monitor NOX exha ust, criteria for exempt units, and methods to be used to provide substitute emissions compliance data during periods when the NOX monitors are offline. Proposed revisions to subsection (c)(1 ) include adding section cross-references to proposed new § 117.405(a) and (b) and proposed revised § 117.410(a) and deleting references to existing § 117.410(b). Proposed revised § 117.440(d), concerning ammonia monitoring requirements, adds section cross-references to proposed new § 117.405(a) and (b) and proposed new § 117.410(a) and deletes a reference to existing § 117.410(b). In addition, The submitted revision proposes a reference to proposed new § 117.405(d)(2) to be consistent with the proposed new § 117.405.

Proposed revised § 117.440(j), concerning data used for compliance, specifies that the methods required in proposed revised § 117.440 must be used to demonstrate compliance with the emission specifications after the initial demonstration of compliance required by proposed revised § 117.435.17 The submitted revision proposes references to proposed new § 117.405(a) and (b) and proposed new § 117.410(a) and repeal of the reference to existing § 117.410(a) and (b).

Finally, proposed revised § 117.440(k) specifies the testing an d retesting requirements for units subject to the emission specifications of proposed new § 117.405(a) or (b) or proposed revised § 117.410(a). The submitted revision proposes deleting existing paragraph (1), which has now been made obsolete by the passing of compliance dates in existing § 117.9030(a) and also contains provisions for units subject to existing § 117.410(a). The amendment of paragraph (1) would be concurrent with the proposed amendment of existing § 117.410(a) and existing § 117.9030(a), concerning IOP emission specifications. The sub mitted revision proposes to move existing subsection (k)(2) to subsection (k)(1). In addition, the commission proposes new references to proposed new § 117.405(a) and (b) and proposed revised § 117.410(a) and remove the reference to existing § 117.410(b). Proposed new paragraph (1) woul d require the owner or operator of units subject to the emission specifications of proposed new § 117.405(a) or (b) or proposed revised § 117.410(a) to test the units as specified in proposed revised § 117.435, Initial Demonstration of Compliance, in accordance with the schedule specified in proposed revised § 117.9030.

The submitted revision proposes to move existing paragraph (3) to proposed amended paragraph (2). Proposed changes also include references to proposed new § 117.405(a) and (b) and proposed

revised § 117.410(a) with removal of the reference to existing § 117.410(b). Proposed amended subsection (k)(2) is a retesting requirement for owners or operators to retest any unit subject to the emission specifications of proposed new § 117.405(a) or (b) or proposed revised § 117.410(a) after any modification that could be reasonably expected to increase the NOX emission rate. This proposed retesting provision applies to units that are not equipped with CEMS or PEMS to monitor

NOX emissions.

Evaluation: This section shows how an affected so urce will continue to demonstrate its initial compliance on an ongoing basis. Testing provides for consistency and compliance determination of

NO X emission specifications. CEMS and PEMS used as a means of showing emission limitations and control requirements. Retesting units not e quipped with CEMS or PEMS will provide for accurate data and replicability of emission information. This section will assist field personnel and the 95% meter running time will assist with enfo rcement. The EPA is proposing approval of all

revisions to § 117.440 of the Texas SIP.

Section 117.445, Notification, Record keeping, and Reporting Requirements The submitted revision proposes removi ng the requirements in existing § 117.445(b)(1) and (2), which specify the notification requirements for units subject to the emission specifications of existing § 117.410(a) and (b), respectively. As mentioned elsewhere in the Section by Section Discussion of this preamble, existing § 117.410(a) is concurrently proposed for amendment due to the passing of compliance dates in existing § 117.9030(a) and because affected units of existing § 117.410(a) are now subject to emission specifications in existing § 117.410(b), which is also concurrently proposed to be moved to proposed § 117.410(a). In addition, The submitted revision proposes § 117.445(b) to contain the provisions of proposed amended § 117.445(b)(2), which detail the notification requirements for units subject to existing § 117.410(b). Proposed § 117.445(b) would also include section cross-references to proposed new § 117.405(a) and (b) and proposed revised § 117.410(a). Under proposed new subsection (b), written notice is re quired at least 15 days in advance of the date18 of any CEMS or PEMS performance eval uation conducted under proposed revised § 117.440 or stack test conducted under proposed revised § 117.435.

The proposed revision of § 117.445(e), specifies the semiannual reporting requirements for owners or operators of any gas-fired engines, incl udes a section cross-reference to proposed new § 117.405. Written reports of excess emissions and the air-fuel ratio monitoring system performance must be

submitted to the executive director.

The proposed revision of § 117.445(f) specifies requirements for written or electronic records for owners or operators of units subject to the requirements of this division. The proposed revision of subsection (f)(4), specifies that records of monthly hours of operation must be maintained for units claiming an exemption based on hours per year of operation, includes section cross-references to proposed § 117.403(b)(2)(D) to reflect proposed changes in § 117.403. The submitted revision proposes to clarify that owners or operators of stationary gas turbin es are also required to maintain records of the purpose of unit operation, such as the identification of the type of emergency

situation.

The submitted revision proposes revisions to exis ting subsection (f)(9) to clarify that records retention of each time a stationary diesel or dual -fuel engine is operated for testing and maintenance refers to testing and maintenance of the diesel or dual-fuel engine itself. Finally, proposed revised § 117.445(f)(10) updates the existing section cross-reference from existing § 117.410(b)(7)(A)(ii) to proposed § 117.410(a)(7)(A)(ii), to coincide with the amendment of existing § 117.410(a) and the proposed re-lettering of existing § 117.410(b) to proposed § 117.410(a).

Evaluation: This section serves as tool to ensure th at an affected source will be in compliance with applicable emission limitations and control requireme nts. This section will assist field personnel with compliance determinations. The EPA is proposin g approval of all submitted revisions to § 117.445

of the Texas SIP.

Section 117.450, Initial Control Plan Procedures The submitted revision proposes revisions to existing § 117.450, concerning the requirements and procedures for submitting an initial contro l plan. The submitted revision proposes in § 117.450(a), (a)(1), (1)(C), and (2) section cross-references to proposed new § 117.405(a) and (b) and proposed

revised § 117.410(a) and to delete references to existing § 117.410(b). The proposed revision of § 117.450(a) requires the owner or operator of any unit at a major source of NOX in the 10-county DFW area that is subject to proposed new § 117.405(a) or (b) or proposed revised § 117.410(a) to submit an initial control plan and lists the content requirements for the initial control plans. Sources in the nine-county DFW area already subject to § 117.410 would have previously been required to submit the initial control plans. Sources subject to proposed new § 117.405 would be required to submit initial control plans by the applicable compliance date.

The submitted revision proposes to revise exis ting subsection (b) to update the section crossreference from existing § 117.9030(b) to proposed revised § 117.9030. Proposed revised § 117.450(b) specifies the initial control plan must be submitted to the Office of Compliance and Enforcement, the appropriate regional office, and the Office of Air by the applicable date specified for initial control plans in proposed revised § 117.9030.19 Finally, The submitted revision proposes to delete existing § 117.450(c), which specifies that for units located in Dallas, Denton, Collin, and Tarrant Coun ties, subject to existing Subchapter B, Division 2, the owner or operator may elect to submit the mo st recent revision of the final control plan required by proposed repealed § 117.254 in lieu of the initial c ontrol plan required by existing subsection (a). The proposed deleted § 117.450(c) would be concurrent with the proposed repeal of existing Subchapter B, Division 2 due to the pa ssing of compliance dates and because sources of NOX previously subject to Subchapter B, Divisi on 2 are now required to comply with more stringent rules in existing Subchapter B, Division 4.

Evaluation: This section establishes the proced ures that an affected source will follow when submitting initial control plans. The proposed re visions will assist with compliance determination activities for affected sources operating in the ten-county DFW area. The EPA is proposing approval of all revisions to § 117.450 of the Texas SIP.

Section 117.452, Final Control Plan Proce dures for Reasonably Available Control Technology The submitted revision proposes a new § 117.452 that would require the owner or operator of any unit subject to proposed new § 117.405(a) or (b) at a major source of NOX to submit a final control report to show compliance with the requirements of proposed new § 117.405.

The proposed revision of § 117.452(a)(1) - (5) specifies the content requirements of the report. The final control report must identify which sections are used to demonstrate compliance. The report must include: the method of NOX control for each unit; the emissions measured by testing required in proposed revised § 117.435; and the specific rule citation for any unit with a claimed exemption from the emission specifications of proposed new § 117.405(a) or (b). In addition, if a compliance stack test report or monitor certificati on report required by proposed revised § 117.435 is not being submitted concurrently with the final control report , the final control report must include the date the compliance stack test report or monitor certification report was submitted, and whether it was sent to the central office, the regional office, or both offices.

The proposed revision of § 117.452(b)(1) - (3) specifies that for sources complying with proposed

revised § 117.423 in addition to the requirements of proposed new subsection (a), the owner or operator shall submit: the calculations used to calculate the 30-day average and maximum daily source cap allowable emission rates; the average daily heat input, variable Hi, specified in proposed

revised § 117.423(b)(1); the maximum daily heat input, variable Hmi, specified in proposed revised § 117.423(b)(2); the method of monitoring emissions; the method of providing substitute emissions data when the NOX monitoring system is not prov iding valid data; and an explanation of the basis

of the values of variables Hi and Hmi.

The proposed revision of § 117.452(c) specifies the report must be submitted to the Office of Compliance and Enforcement, the appropriate re gional office, and the Office of Air by the applicable date specified for final control plans in proposed revised § 117.9030(a). The plan must be updated with any emission compliance measurements submitted for units using a CEMS or PEMS and complying with the source cap rolling 30-day average emission limit, according to the applicable schedule in proposed revised § 117.9030(a).20 Evaluation: This section will assist with compliance determination activities for affected sources operating in the ten-county DFW area. The repor t will contain information concerning maximum daily source cap allowable emission rates; the average daily heat input; CEMS; PEMS, stack test, and stack, and when applicable, stack retest . The EPA is proposing approval of new § 117.452 of the

Texas SIP.

Section 117.454, Final Control Plan Procedur es for Attainment Demonstration Emission Specifications The submitted revision proposes revisions to existing § 117.454 which require the owner or operator of any unit subject to proposed revised § 117.410 at a major source of NOX to submit a final control report to show compliance with the requirements of proposed revised § 117.410. The proposed

revision of § 117.454(a)(4) updates the reference to " relative accuracy test audit" to " monitor certification" consistent with the concurrently proposed revision to § 117.435(c). The proposed revision of § 117.454(b)(2)(B) corrects a section cross-reference from § 117.423(b)(1) to § 117.423(b)(2), for sources choosing the source cap compliance option.

Finally, the proposed § 117.454(c) specifies the report must be submitted to the Office of Compliance and Enforcement, the appropriate re gional office, and the Office of Air by the applicable date specified for final control plans in proposed revised § 117.9030.

Evaluation: The proposed revisions to Section 11 7.454 will assist with compliance determination activities for affected sources opera ting in DFW area. The updates to "relative accuracy test audit" to

"monitor certification" references will make th is section consistent with section 117.423 when a source chooses source cap approach to meet its applicable emission limitations and reporting requirements. The EPA is proposing approval of all revisions to § 117.454 of the Texas SIP.

Section 117.456, Revision of Final Control Plan The submitted revision proposes revisions to existing § 117.456 by adding in paragraph (1) a section cross-reference to proposed new § 117.405. The section specifies the conditions under which a revised final control plan may be submitted by the owner or operator, along with any required permit applications. Paragraphs (1) - (3) specify that such a plan must adhere to the requirements and the final compliance dates of the division, and that for sources complying with proposed new § 117.405 or proposed revised § 117.410, replacement new units may be included in the control plan. Also, for sources complying with proposed revised § 117.423, any new unit must be included in the source cap if the unit belongs to an equipment category that is included in the source cap. Evaluation: This section provides the latest up-to-date changes for final control plans. By including new units in the source cap provision the final cont rol plan report will be an all-inclusive document. The EPA is proposing approval of all revisions to § 117.456 of the Texas SIP.



### SUBCHAPTER C, COMBUSTION CONT ROL AT MAJOR UTILITY ELECTRIC GENERATION SOURCES IN OZONE NONATTAINMENT AREAS, DIVISION 2, DALLAS-FORT WO RTH OZONE NONATTAINMENT AREA

UTILITY ELECTRIC GENERATION SOURCES21 The submitted revision proposes repeal of existing Subchapter C, Division 2, which has been made obsolete by the passing of compliance dates beca use sources of NOX previously subject to this division are now required to comply with more string ent rules in existing Subchapter C, Division 4.



### DIVISION 4, DALLAS-FORT WORTH EIGHT-HOUR OZONE

NONATTAINMENT AREA UTILITY EL ECTRIC GENERATION SOURCES

To address new RACT requirements for sources of NOX located in Wise County, The submitted revision is proposing revisions in Subchapter C, Divi sion 4, that would revise existing rule language and requirements associated with any major utility electric generation source of NOX in the 10- county DFW 2008 eight-hour ozone nonattainment ar ea. The revised definition of a major source of NOX in Wise County is in proposed revised §117.10(29)(C) and includes any stationary source or group of sources located within a contiguous area and under common control that emits or has the potential to emit 100 tpy of NOX.

Section 117.1303, Exemptions The proposed revisions to § 117.1303 clarify exemption criteria used to exempt units from specified requirements of proposed revised Subchapter C, Division 4. The submitted revision is proposing to remove the existing exemption in § 117.1303(a)(1), which applies to any new auxiliary steam boiler or stationary gas turbine placed into service after November 15, 1992. This revision is proposed to make the utility rules that apply to gas turbines in the DFW area consistent with the major source industrial rules in the DFW area and to provide a simpler RACT demonstration for the affected utility sources. Affected auxiliary steam boilers and gas turbines would be required to meet the NOX emission specifications and monitoring and testi ng requirements, which are not proposed for revision, of proposed revised Subchapter C, Di vision 4. Based on a TCEQ review of the 2012 EI and available air permit information, the TCEQ expects that all existing auxiliary steam boilers in the nine counties of the DFW 1997 eight-hour ozone nonattainment area were constructed prior to the exemption date of November 15, 19 92. Therefore, the exemption in § 117.1303(a)(1) did not apply to these existing units, and no impact is expec ted as a result of the proposed repeal of the exemption. New units would either qu alify for the existing exemption in § 117.1303(a)(2) based on annual heat input or would be required to co mply with the provisions of proposed revised Subchapter C, Division 4. No auxiliary stea m boilers were identified in Wise County.

After reviewing the 2012 EI and available air permit information for all existing gas turbines in the nine counties of the DFW 1997 eight-hour ozone nonattainment area, the TCEQ has concluded that all existing gas turbines in the nine counti es of the DFW area were pl aced into service after November 15, 1992. Although the proposed removal of the exemption in § 117.1303(a)(1) would affect these existing units, all of the affected turbines would already meet the NOX emission specifications and monitoring requirements of propos ed revised Subchapter C, Division 4. Existing monitoring provisions require owners or ope rators of units subject to the NOX emission specifications to install, calibrate, maintain, an d operate a NOX emissions monitoring system. The EPA proposes approval of this.

Because these units already meet the NOX emission specifications and monitoring requirements of Subchapter C, Division 4, The submitted revision does not expect adverse impacts to owners or22 operators of affected units in the nine counties of the DFW area as a result of deleting the requirement in §117.1303(a)(1). New units would either qualify for the existing exemption in §117.1303(a)(3)(B) based on unit operating hours or would be required to comply with the provisions of proposed revised Subchapter C, Di vision 4. One utility electric generation source in Wise County was identified as an affected source. Based on 2012 EI information, this source would already meet the NOX emission specifications and monitoring requirements of proposed revised Subchapter C, Division 4. The remaining paragraphs will be renumbered accordingly.

The submitted revision proposes revising the opera ting hours limit for exemption criteria for stationary gas turbines and stationary interna l combustion engines in proposed §117.1303(a)(2)(B) from a rolling 12-month average to a rolling aggrega te 12-month basis. The owner or operator of an affected unit would sum all operating hours for a consecutive 12-month period, and continue doing so on a rolling 12-month basis, as opposed to calcul ating the average of all operating hours during a consecutive 12-month period. This would more accu rately reflect the intent of the rule and how an affected unit would demonstrate compliance with the operating restriction of a total of 850 hours

per year.

Evaluation: The EPA proposes approval of these exemptions because the revision makes the utility rules that apply to gas turbines in the DFW NAA consistent with the major source industrial rules in the DFW NAA. This provides a more effici ent RACT demonstration for the affected utility sources. The proposed revisions will make utility ru les consistent with the major source industrial rules in the DFW area and provide a simpler RACT demonstration for the affected utility sources. This revision will provide for consistency and clar ification of RACT demonstration. The EPA is proposing approval of all revisions to § 117.1303 of the Texas SIP.

Section 117.1310, Emission Specifications for Eight-Hour Attainment Demonstration

Proposed revised § 117.1310(b) establishes emission specifications of related emissions for units that are subject to the emission specifications of subsecti on (a) of this section. The submitted revision proposes deleting existing § 117.1310(b)(1) and (2) due to removing ammonia emission specification found in existing subsection (b)(2)(B) and restructur ing of subsection (b) that would be necessary to

conform to current Texas Register formatting requirements. Existing paragraph (2) specifies ammonia emission specifications for units that are subject to the NOX emission specifications of § 117.1310(a). Existing paragraph (2)(A) applies only to units that inject urea or ammonia into the exhaust stream for NOX control while existing pa ragraph (2)(B) applies to all units. Existing § 117.1310(b)(2)(B) cites a RACT emission specification for ammonia that is now obsolete, and The submitted revision proposes that an ammonia emission specification is needed only for units that

use urea or ammonia for control of NOX emissions.

In restructuring subsection (b), The submitted revisi on proposes to move the existing provisions of
§ 117.1310(b)(1)(A) to proposed § 117.1310(b)(1)(A) and (B). Th e existing provisions of
§ 117.1310(b)(1)(B) are proposed to be moved to proposed § 117.1310(b)(2). The existing provisions

of § 117.1310(b)(2)(A) are proposed to be moved to proposed § 117.1310(b)(3)(A) and (B).

Evaluation: The EPA is proposing approval of all revisions to § 117.1310 of the Texas SIP.23 Section 117.1325, Alternative Ca se Specific Specifications Minor stylistic, non-substantive changes are proposed in existing subsection (a) of this section. No other changes are proposed.

Evaluation: The revisions are ministerial or edit orial in conformance with the Texas Register requirements. The EPA is proposing approval of all revisions to § 117.1325 of the Texas SIP.

Section 117.1335, Initial Demonstration of Compliance The submitted revision proposes a paragraph (4) in existing § 117.1335(d) to specify the monitoring procedures to be followed for units complying with a NOX emission specification in lb/MMBtu on a block one-hour average. Existing rule provis ions address monitoring procedures for units complying with a NOX emission specification in lb/MMBtu on a rolling 30-day average and on a rolling 24-hour average; however, they do not addr ess how units must comply with a NOX emission specification in lb/MMBtu on a block one-hour average. The submitted revision proposes to renumber existing paragraph (4) to paragraph (5 ). In addition, The submitted revision proposes a paragraph (6) to specify the monitoring procedures to be followed for units complying with a NOX emission specification in lb/MMBtu on a rolling 168-hour average.

Similar to the approach for proposed paragraph (4), existing rule provisions do not address how units must comply with a NOX emission specification in lb/MMBtu on a rolling 168-hour average. The submitted revision proposes that the 168-hour average emission rate is calculated using the equation in § 117.1310(a)(1)(D). In addition, The submitted revision proposes to clarify that the system-wide heat input weighted average is calcula ted for each hour, and the average of that hourly data during the 168-hour test period is used to demonstrate compliance. Finally, The submitted revision proposes to renumber existing paragraph (5) to proposed paragraph (7).

Evaluation: This section will establish the baselin e plan by which an affected source meets its applicable emission limitations revision and corresponding rolling average periods. It assures that the monitoring data are accurate, replicable, and cert ified accordingly. The EPA is proposing approval

of all revisions to § 117.1335 of the Texas SIP.

Section 117.1340, Continuous Demonstration of Compliance The submitted revision proposes changes to existing § 117.1340, which details the operating, monitoring, and testing procedures required by owne rs or operators of units subject to the emission specifications of proposed revised § 117.1310 in order to demons trate continuous compliance. Proposed revised § 117.1340(c), concerning ammonia monitori ng requirements, up dates a reference from existing § 117.1310(b)(2)(A) and to proposed § 117.1310(b)(3) to coincide with the changes proposed in § 117.1310(b). Alternative NOX monitoring pr ovisions for auxiliary steam boilers are provided in existing subsection (f). Proposed revisions to § 117.1340(f) include rule language to clarify that the alternative monitoring provisions for using a CEMS apply to monitoring only NOX emissions. Proposed revised § 117.1340(h)(2) includes additional rule language to clarify that stationary gas turbines that are not rated less than 30 megawatts (M W) or that are not peaking gas turbines that use steam or water injection must use either a CEMS or PEMS to comply with the monitoring24 requirements for stationary gas turbines that ar e subject to the stationary gas turbine emission specifications of § 117.1310.

Evaluation: The EPA is proposing approval of all revisions to § 117.1340 of the Texas SIP.

Section 117.1345, Notification, Record keeping, and Reporting Requirements Proposed revised subsection (d) specifies the semiannual reporting requirements for owners or operators of units using a CEMS, PEMS, or steam-to -fuel or water-to-fuel ratio monitoring system under proposed revised § 117.1340. Proposed changes to subsection (d)(5) add a PEMS to the list of monitoring systems for which the owner or operator must submit a summary report and an excess emission report if the monitoring system downtime fo r the reporting period is greater than or equal to 5.0% of the total unit operating time for th e reporting period. Proposed revised subsection (e)(3) also clarifies that the owner or operator of each unit subject to the requirements of the division shall maintain records of the quantity and type of each fuel burned in the unit. All other proposed changes to existing § 117.1345 are minor stylistic, non-substantive changes.

Evaluation: This section will assist field pers onnel with compliance determinations to ensure downtime does not exceed 5% of total operating time. Other revisions to 117.1345 are editorial and stylistic. The EPA is proposing approval of all revisions to § 117.1345 of the Texas SIP.

Section 117.1350, Initial Control Plan Procedures The submitted revision proposes to delete existing subsection (c), which contains references to existing § 117.1110 and § 117.1154, concurrently proposed for repeal, to be consistent with the proposed repeal of existing Subchapter C, Division 2.

The proposed revisions to Section 117.1350 will remove subsection (c) for consistency with § 117.1110 and § 117.1154. The EPA is proposing a pproval of all revisions to § 117.1350 of the Texas

SIP.

Section 117.1354, Final Control Plan Procedur es for Attainment Demonstration Emission Specifications Proposed revised § 117.1354 requires the owner or opera tor of utility boilers listed in § 117.1300 at a major source of NOX to submit a final control plan to show compliance with the requirements of proposed revised § 117.1310. Proposed § 117.1354(a)(3) updates the reference to " relative accuracy test

audit" to " monitor certification" consistent with the language in § 117.1335(c). All other changes are minor revisions to update TCEQ office names and references.

Evaluation: This section will provide for consistency with § 117.1335(c). The EPA is proposing approval of all revisions to §117.1354 of the Texas SIP.



### SUBCHAPTER G, GENERAL MONITORING AND TESTING REQUIREMENTS, DIVISION 1, COMPLIANCE STACK TESTING AND REPORT REQUIREMENTS25 Section 117.8000, Stack Testing Requirements The submitted revision proposes § 117.8000(e) to establish emission testing provisions for boilers and process heaters that are used on a temporary basis and are therefore installed or relocated to an account to be operated for a brief period of time . The owner or operator of a site that temporarily brings a unit on-site for short periods would not have sufficient amount of time to perform the testing requirements of the rule. These proposed re quirements would be applicable to affected units in all areas covered by Chapter 117. Proposed sub section (e) would provide compliance flexibility to owners or operators that use temporary boilers or process heaters for less than 60 consecutive calendar days by allowing the owner or operator to use previous stack test results conducted on the boiler or process heater or a manufacturer's guar antee of performance. The previous testing results or manufacturer's guarantee must be for the unit that would be newly installed at the account and not testing results or guarantee of performance for a similar unit make or model. For the purposes of this proposed subsection, the term "relocate" or “relocated” means to newly install at an account,

as defined in § 101.1, Definitions, a boiler or process heater from anywhere outside of that account. Proposed subsection (e)(1) specifies that if previous testing results are used, testing must have been conducted on the same boiler or process heater in accordance with § 117.8000(b) - (d). In addition, the owner or operator of the site temporarily inst alling the unit shall maintain a record of the previous test report as specified by the recordkeeping requirements under Chapter 117 applicable to

the site.

Proposed subsection (e)(2) specifies that the owner or operator shall physically remove the unit

from the account no later than 60 consecutive calend ar days after installing the unit at the account. If the owner or operator chooses not to physically remove the unit from the account, the owner or operator shall comply with the testing requirements as specified in § 117.8000(b) - (d). Lastly, the submitted revision proposes that extensions to th e 60 consecutive calendar days limitation of proposed subsection (e) would not be provided. This is to prevent circumvention of satisfying the applicable initial demonstration of compliance and testing requirements that would otherwise apply to the affected stationary boiler or stationary pr ocess heater subject to Chapter 117. In addition, the submitted revision does not anticipate that these affected units would be using a CEMS or PEMS for demonstrating compliance with the requirements of Chapter 117.

Evaluation: The proposed section establishes emissi on-testing provisions for boilers and process heaters and provides operational flexibility. The EPA is proposing approval of all revisions to
§ 117.8000 of the Texas SIP.



### SUBCHAPTER H, ADMINISTRATIV E PROVISIONS, DIVISION 1,

COMPLIANCE SCHEDULES

Section 117.9010, Compliance Schedule for Da llas-Fort Worth Ozone Nonattainment Area Major Sources The submitted revision proposes the repeal of existing § 117.9010, which has been made obsolete by the passing of compliance dates because sources of NOX previously subject to this section are now required to comply with more stringent rules in proposed revised § 117.9030.26 Evaluation: The existing 117.90 10 is now outdated, and repla ced with§117.9030. The EPA is proposing approval of all revisions to § 117.9010 of the Texas SIP.

Section 117.9030, Compliance Schedule for Dallas-Fort Worth Eight-Hour Ozone Nonattainment Area Major Sources The submitted revision proposes deleting existing § 117.9030(a), concerning compliance schedule for IOP emission specifications. With the passing of the compliance date for eight-hour ozone attainment demonstration emission specifications in existing § 117.9030(b), these gas-fired engines are now subject to emission specifications for eight-hour ozone attainment demonstration in existing § 117.410(b), which The submitted revision is proposing as revised § 117.410(a).

The submitted revision proposes a new subsection (a) in § 117.9030, concerning RACT emission specifications, to specify the compliance schedule requirements for units subject to the emission specifications of proposed new § 117.405(a) and (b). Proposed § 117.9030(a)(1) requires the owner or operator of any stationary source of NOX in the 10-county DFW 2008 eight-hour ozone nonattainment area that is a major source of NOX and is subject to proposed new § 117.405(a) or (b) to submit the initial control plan required by proposed revised § 117.450 no later than June 1, 2016, and to comply with all other requirements of proposed revised Subchapter B, Division 4 as soon as practicable, but no later than January 1, 2017. Proposed § 117.9030(a)(2) specifies that the owner or operator of any stationary source of NO X that becomes subject to the requirements of proposed revised Subchapter B, Division 4 on or after January 1, 2017, shall comply with the requirements of Subchapter B, Division 4 as soon as practicable, but no later than 60 days after becoming subject to those provisions. For example, new units placed into service after January 1, 2017 would be required to comply within 60 days after startup of the unit. Existing units previously exempt from the rule but no longer qualifying for that exemption after January 1, 2017 would be required to comply with the proposed rule no later th an 60 days after the unit no longer qualifies for the exemption.

The proposed revision of § 117.9030(a)(3) specifies that if Wise County is not designated a nonattainment county as part of the DFW 2008 eight-hour ozone nona ttainment area, an owner of operator of any unit located at a major stationary source of NOX located in Wise County would not be required to comply with the applicable require ments of proposed revised Subchapter B, Division 4. The submitted revision would publish notice of a change in nonattainment status for Wise County

in the Texas Register . This change is proposed because Texa s is currently in litigation over the inclusion of Wise County in the DFW 2008 ei ght-hour ozone nonattainment area, as discussed elsewhere in this preamble. As the submitted revisi on cannot predict the outcom e of this litigation at this time, the submitted revision is proposing rules that will ensure that sources within Wise County will be properly accounted for in the DFW 2008 attainment demonstration SIP.

Proposed revisions to existing § 117.9030(b), concerning eight-hour ozone attainment demonstration emission specifications, include updates to section cross-references. Proposed revised § 117.9030(b)(1), (1)(B), (B)(i) and (ii) include deleting the references to existing § 117.410(b) and proposing references to § 117.410(a). Proposed revised paragraph (1)(C) deletes the reference to existing § 117.410(g) and adds a reference to proposed § 117.410(f).27 Evaluation: The proposed revisions to the compliance schedules will provide for implementation of the 2008 eight-hour ozone NAAQS, and assist with enforcement of the rule. The EPA is proposing approval of all revisions to § 117.9030 of the Texas SIP.

Section 117.9110, Compliance Schedule for Da llas-Fort Worth Ozone Nonattainment Area Utility Electric Generation Sources The submitted revision proposes repeal of existing § 117.9110, which has been made obsolete by the passing of compliance dates because sources of NOX previously subject to this section are now required to comply with more stringent rules in proposed § 117.9130.

Evaluation: The existing 117.9110 is now outdated an d replaced with the more up to date §117.9130. The EPA is proposing approval of all revisions to § 117.9110 of the Texas SIP.

Section 117.9130, Compliance Schedule fo r Dallas-Fort Worth Eight-Hour Ozone Nonattainment Area Utility El ectric Generation Sources Proposed revised § 117.9130 specifies the compliance schedule for owners or operators of electric utilities subject to proposed revised Subchapter C, Division 4. Proposed subsection (a), which specifies the compliance schedule for existing electr ic utilities subject to the existing rule, deletes a reference to the existing DFW eight-hour ozone nonattainment area and proposes the following new list of counties: Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, and Tarrant Counties. This change is proposed to be consistent with the proposed revised definition of DFW eight-hour ozone nonattainment area in § 117.10 and to distinguish between the existing compliance schedule for sources currently subject to the rule and those that would be newly subject by the proposed rulemaking.

The submitted revision proposes § 117.9130(b) to detail the compliance schedule for auxiliary steam boilers and stationary gas turbines located in Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, and Tarrant Counties that would be affected by the proposed amendment to the existing exemption in § 117.1303(a)(1). Affected auxiliary steam boilers and stationary gas turbines would be units that were placed into service after November 15, 1992, and these affected units would be required to meet the NOX emission specifications and monitoring and testing requirements, which are not proposed for revision, of proposed revised Subchapter C, Division 4. Proposed § 117.9130(b)(1) requires the owner or operator to submit the initial control plan required by proposed revised § 117.1350 by no later than June 1, 2016. Proposed § 117.9130(b)(2) specifies that the owner or operator must comply with all other requirements of proposed revised Subchapter C, Division 4 as soon as practicable but no later than January 1, 2017.

The submitted revision proposes § 117.9130(c) to detail the compliance schedule for electric utilities located in Wise County subject to the proposed rule. Proposed § 117.9130(c)(1) requires the owner or operator to submit the initial contro l plan required by proposed revised § 117.1350 by no later than June 1, 2016. Proposed subsection (c)(2) specifies that the owner or operator must comply with all other requirements of proposed revised Subchap ter C, Division 4 as soon as practicable but no later than January 1, 2017. The submitted revisi on proposes to move existing subsection (b) to proposed subsection (d).28 Proposed § 117.9130(d) specifies that for electric utilit ies in Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, or Tarrant County that become subject to Subchapter C, Division 4 on or after March 1, 2009, and for electric utilities in Wise County that become subject to Subchapter C, Division 4 on or after January 1, 2017, the owne r or operator must comply as soon as practicable but no later than 60 days after becoming subject.

Finally, proposed § 117.9130(e) specifies that if Wise County is not designated a nonattainment county as part of the DFW 2008 eight-hour ozone nonattainment area, an owner of operator of an electric utility located in Wise County would not be required to comply with the applicable requirements of proposed revised Subchapter C, Division 4. The submitted revision would publish notice of a change in nonattainment status for Wise County in the Texas Register . This change is proposed because Texas is currently in litigati on over the inclusion of Wise County in the DFW 2008 eight-hour ozone nonattainment area, as di scussed elsewhere in this preamble. As the submitted revision cannot predict the outcome of this litigation at this time, The submitted revision is proposing rules that will ensure that sources with in Wise County will be properly accounted for in

the DFW 2008 attainment demonstration SIP.

Evaluation: The proposed revisions to the compliance schedules will provide for implementation of the 2008 eight-hour ozone NAAQS, and assist with enforcement of the rule. The EPA is proposing approval of all revisions to § 117.9130 of the Texas SIP.



### DIVISION 2, COMPLIANCE FLEXIBILITY

Section 117.9800, Use of Emissi on Credits for Compliance The proposed revision of § 117.9800 includes section cross-reference updates to be consistent with proposed repeal of Subchapter B, Division 2, an d Subchapter C, Division 2. The submitted revision proposes revisions to existing subsections (a)(1) - (5 ), (b), and (d) to reflect proposed changes in the other subchapters. Proposed revised subsection (a)(1 ) would also add a section cross-reference to proposed new § 117.405.

Evaluation: The revisions in this section ministerial or editorial in nature. The EPA is proposing approval of all revisions to § 117.9800 of the Texas SIP.

Section 117.9810, Use of Emission Reducti ons Generated from the Texas Emissions Reduction Plan (TERP) The submitted revision proposes revisions to existing § 117.9810, which would remove crossreferences to be consistent with the proposed repeal of Subchapter B, Division 2, and Subchapter C, Division 2 and renumber paragraphs accordingl y. Proposed revised subsection (a)(1) would add a new reference to proposed new § 117.405. The submitted revision proposes to renumber existing subsection (a)(6) to proposed subsection (a)(2) to reflect proposed subsection (a)(2) - (5).

Evaluation: The revisions in this section ministerial or editorial in nature. The EPA is proposing approval of all revisions to § 117.9810 of the Texas SIP.