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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, 2015 
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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.gov 
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Table of Contents 

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

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

SUBCHAPTER B, COMBUSTION CONTROL AT MAJOR INDUSTRIAL, COMMERCIAL, 

AND INSTITUTIONAL SOURCES IN OZONE NONATTAINMENT AREAS, DIVISION 

2, DALLAS-FORTWORTH OZONE NONATTAINMENT AREA MAJOR SOURCES ......... 7

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

AREA MAJOR SOURCES ......................................................................................................................... 7

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

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

Section 117.405, Emission Specifications for Reasonably 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 ........................................................................ 16

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 NONATTAINMENT AREAS, DIVISION 2, 

DALLAS-FORT WORTH OZONE NONATTAINMENT AREA UTILITY ELECTRIC 

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

DIVISION 4, DALLAS-FORT WORTH EIGHT-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 .................................................................. 22

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

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

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

Section 117.1354, Final Control Plan Procedures for Attainment Demonstration Emission 

Specifications ............................................................................................................................................... 24

SUBCHAPTER G, GENERAL MONITORING 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 Dallas-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 Compliance ................................................................ 28

Section 117.9810, Use of Emission Reductions Generated from the Texas Emissions Reduction 

Plan (TERP) ................................................................................................................................................. 28
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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 relating 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 stringent rules in existing divisions relating to the 

expanded nine-county DFW area. The submitted 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-Brazoria 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, Rockwall, 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 definition of DFW eight-hour 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 independent power producers in the ozone nonattainment 

areas. Systems that are owned or operated by independent 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, Subchapter 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 nonattainment 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 Beaumont-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-Brazoria 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 specific combustion unit types that are part of 

electric power generating systems located in the Houston-Galveston-Brazoria ozone nonattainment 
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area that are subject to Subchapter 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 applies 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 references to the Electric Reliability Council of Texas 

(ERCOT) Protocols to the most recent published 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 applicable 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 references to DFW and DFW eight-hour ozone 

nonattainment area and adding Collin, Dallas, Denton, 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 nonattainment area and to reflect the difference in the 

applicability threshold because of the different classifications between Wise County and the other 

nine 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 nonattainment 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 stationary 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 NOX rules and assist in compliance 

determination for Wise County and the remaining nine 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. 
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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 dates because sources of NOX previously subject to 

this division are now required to comply with more 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 stationary sources of NOX in the other nine 

counties that are not already addressed under the current 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 located 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 area 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, stationary 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 NOX in nine 

Counties within the DFW area. This is consistent with section 182(b) of the CAA. The EPA is 

proposing approval of all revisions to §117.400 of the Texas SIP. 
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Section 117.403, Exemptions 

Proposed revisions to §117.403 clarify exemption criteria of units that would be exempt from 

specified requirements of proposed revised Subchapter 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 for 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 maintenance purposes up to 100 hours per year refers to 

testing and maintenance of the stationary gas turbine 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-month rolling basis is the preceding 12-month total, which matches 

the 100 hours per year limit. This would more accurately 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 engines would be on a rolling 12-month basis and not on a 

rolling 12-month average and thus how an affected unit would demonstrate 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 proposes 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 more 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 the 
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proposed NOX emission specifications are exempted from the provisions of this division, except as 

specified in proposed revised §§117.440(i), 117.445(f)(4), and 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 exempted. This exemption level is proposed to be 

consistent with previous RACT exemption approaches for ICI process heaters located in the DFW 

area and the Houston-Galveston-Brazoria ozone nonattainment area. 

The following stationary gas turbines and stationary internal combustion engines 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 verification 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 gas 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 criterion 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 proposing emission specifications for these unit types. 

Proposed §117.403(b)(5) specifies an exemption for stationary gas-fired engines with a horsepower 

(hp) rating of less than 50 hp. This is consistent 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 units or type of units will be exempt as major NOX

sources, and not subject to 182(b) of the CAA. Identification 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 0.12 
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pounds per million British thermal units (lb/MMBtu) emission specification for wood fuel-fired 

boilers is based on the permitted Best Available Control 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). The unit identified in Kaufman County in the 2012 

EI currently operates with SCR for NOX control 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 particular 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 wood fuel-fired boilers in general. 

Proposed new §117.405(b) includes the proposed new emission 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 may 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 process 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 specifications 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-fired rich-burn and lean-burn, reciprocating internal 

combustion engines. Gas-fired, rich-burn engines 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, modified, reconstructed, or relocated. 

Any White Superior, model 8GTL825, gas-fired, lean-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 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. Finally, any Fairbanks Morse, model MEP-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 limited 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-burn engines. In some cases, 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 emission specification represents RACT for gas-fired, 

rich-burn engines based on the low cost and wide-spread demonstrated effectiveness of NSCR with 

meeting this control level. 
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The proposed revision provides specific NOX emission specifications based on engine make and 

model for the White Superior, Clark, and MEP units 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 technological 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 current emission specifications for stationary gasfired, lean-burn engines in the other nine counties 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 revision 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 revision's adoption of the emission specifications for 

gas-fired, lean-burn engines in the nine-county 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 necessary to reach attainment can, and may, go 

beyond RACT requirements. Some of the NOX control 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 would fulfill RACT, the distinction is necessary in 

order to make clear the submitted revision's intent 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 County. 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 the 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 have already been retrofitted with dry low-NOX 
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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 time, 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 units 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 subparagraph (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 units 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 emission 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 specification 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 PEMS 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 emission 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 averaging period for units equipped with CEMS or 

PEMS for ammonia, and on a block one-hour averaging 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 the NOX emission specifications 

of proposed new §117.405(a) or (b). Proposed new subsection (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 realized. The proposed subsection (e)(3) specifies that 
13 

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 proposed 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, 2012 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 NOX sources subject to 182(b) of the CAA and 30 TAC Chapter 

117 control requirements will assist in compliance 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 Attainment 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 emission specifications under existing §117.410(a) for 

stationary, gas-fired rich-burn and lean-burn reciprocating 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 area. 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). In addition, The submitted revision proposes to specifically 

list Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, or Tarrant County in 

proposed subsection (a) to make clear that the emission specifications provided in the subsection are 

only applicable in those counties and because emission 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 the 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 addition, 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 paragraph (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 engines 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 clarify that testing or maintenance associated 

with the operating restriction of any stationary diesel 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 NOX emission limitations that are more stringent than RACT and 

normally result in additional NOX reductions for achieving attainment under the 2008 eight-hour 

ozone NAAQS. This distinction and county delineation will enhance the overall 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 section 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 exponential power in the equation from a positive to 

a negative number. This change would allow the units, Btu and MMBtu, of the equation to properly 
15 

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 cross-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) specifies that the shutdown must have occurred 

after December 31, 2012, for units 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 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 

(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 operational flexibility to the source to meet the required 

NOX 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 Case 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 Specifications provide operational flexibility while a 

source meet its applicable emission limitation. The 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 cross-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 compliance 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 the seven-day drift test. 

Evaluation: This section will establish the baseline 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 Demonstration 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-fired boilers in the 10-county DFW 2008 eight-hour 

ozone nonattainment area would demonstrate compliance with the monitoring provisions of 

proposed revised Subchapter B, Division 4 through either fuel use records that would be required in 

proposed revised §117.445(f) or the alternative monitoring 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 exhaust, 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 and 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 submitted 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) would 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 source will continue to demonstrate its initial 

compliance on an ongoing basis. Testing provides for consistency and compliance determination of 

NOX emission specifications. CEMS and PEMS used as a means of showing emission limitations 

and control requirements. Retesting units not equipped 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 enforcement. The EPA is proposing approval of all 

revisions to §117.440 of the Texas SIP. 

Section 117.445, Notification, Recordkeeping, and Reporting Requirements 

The submitted revision proposes removing 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 required at least 15 days in advance of the date 
18 

of any CEMS or PEMS performance evaluation 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, includes 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 turbines 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 existing 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 that an affected source will be in compliance with 

applicable emission limitations and control requirements. This section will assist field personnel with 

compliance determinations. The EPA is proposing 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 control 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 existing 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 Counties, subject to existing Subchapter B, Division 

2, the owner or operator may elect to submit the most recent revision of the final control plan 

required by proposed repealed §117.254 in lieu of the initial control 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 passing of compliance dates and because sources of 

NOX previously subject to Subchapter B, Division 2 are now required to comply with more 

stringent rules in existing Subchapter B, Division 4. 

Evaluation: This section establishes the procedures that an affected source will follow when 

submitting initial control plans. The proposed revisions 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 Procedures 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 certification 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 providing 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 regional 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 report 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 Procedures 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 regional 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 117.454 will assist with compliance determination 

activities for affected sources operating in DFW area. The updates to "relative accuracy test audit" to 

"monitor certification" references will make this 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 control 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 CONTROL AT MAJOR UTILITY ELECTRIC 

GENERATION SOURCES IN OZONE NONATTAINMENT AREAS, 

DIVISION 2, DALLAS-FORT WORTH OZONE NONATTAINMENT AREA 

UTILITY ELECTRIC GENERATION SOURCES 
21 

The submitted revision proposes repeal of existing Subchapter C, Division 2, which has been made 

obsolete by the passing of compliance dates because sources of NOX previously subject to this 

division are now required to comply with more stringent rules in existing Subchapter C, Division 4. 

DIVISION 4, DALLAS-FORT WORTH EIGHT-HOUR OZONE 

NONATTAINMENT AREA UTILITY ELECTRIC GENERATION SOURCES 

To address new RACT requirements for sources of NOX located in Wise County, The submitted 

revision is proposing revisions in Subchapter C, Division 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 area. 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 testing requirements, which are not proposed for 

revision, of proposed revised Subchapter C, Division 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, 1992. Therefore, the exemption in §117.1303(a)(1) did not apply 

to these existing units, and no impact is expected as a result of the proposed repeal of the 

exemption. New units would either qualify for the existing exemption in §117.1303(a)(2) based on 

annual heat input or would be required to comply with the provisions of proposed revised 

Subchapter C, Division 4. No auxiliary steam 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 counties of the DFW area were placed 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 proposed revised Subchapter C, Division 4. Existing 

monitoring provisions require owners or operators of units subject to the NOX emission 

specifications to install, calibrate, maintain, and 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 or 
22 

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, Division 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 operating hours limit for exemption criteria for 

stationary gas turbines and stationary internal combustion engines in proposed §117.1303(a)(2)(B) 

from a rolling 12-month average to a rolling aggregate 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. This would more accurately 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 efficient RACT demonstration for the affected utility 

sources. The proposed revisions will make utility rules 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 clarification 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 subsection (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 restructuring 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 paragraph (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 revision proposes to move the existing provisions of 

§117.1310(b)(1)(A) to proposed §117.1310(b)(1)(A) and (B). The 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 Case 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 editorial 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 provisions 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 address 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 calculated 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 baseline 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 certified 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 owners or operators of units subject to the emission 

specifications of proposed revised §117.1310 in order to demonstrate continuous compliance. 

Proposed revised §117.1340(c), concerning ammonia monitoring requirements, updates 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 provisions 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 (MW) or that are not peaking gas turbines that use 

steam or water injection must use either a CEMS or PEMS to comply with the monitoring 
24 

requirements for stationary gas turbines that are 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, Recordkeeping, 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 for the reporting period is greater than or equal 

to 5.0% of the total unit operating time for the 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 personnel 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 approval of all revisions to §117.1350 of the Texas 

SIP. 

Section 117.1354, Final Control Plan Procedures for Attainment Demonstration Emission 

Specifications 

Proposed revised §117.1354 requires the owner or operator 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 REQUIREMENTS 
25 

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 requirements would be applicable to affected units 

in all areas covered by Chapter 117. Proposed subsection (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 guarantee 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 installing 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 calendar 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 the 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 process 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 emission-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, ADMINISTRATIVE PROVISIONS, DIVISION 1, 

COMPLIANCE SCHEDULES 

Section 117.9010, Compliance Schedule for Dallas-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 117.9010 is now outdated, and replaced 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 NOX 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 than 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 nonattainment 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 requirements 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 Texas is currently in litigation over the 

inclusion of Wise County in the DFW 2008 eight-hour ozone nonattainment area, as discussed 

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 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 Dallas-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 and 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 for Dallas-Fort Worth Eight-Hour Ozone 

Nonattainment Area Utility Electric 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 electric 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 control 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 Subchapter C, Division 4 as soon as practicable but no 

later than January 1, 2017. The submitted revision proposes to move existing subsection (b) to 

proposed subsection (d). 
28 

Proposed §117.9130(d) specifies that for electric utilities 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 owner 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 litigation over the inclusion of Wise County in the DFW 

2008 eight-hour ozone nonattainment area, as discussed 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 within 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 Emission 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, and 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 Reductions 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 accordingly. 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.