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Chapter 10

Monitoring, Recordkeeping, and Reporting and Other Issues

Contents

10.1 Monitoring and Compliance ................................................................................................ 2

10.2 Recordkeeping ................................................................................................................... 13

10.3 Reporting............................................................................................................................ 15

10.4 Regulatory Text ................................................................................................................. 17

10.4.1 Subpart TTTT or Subpart Da and KKKK...................................................................... 23

10.4.2 Definitions...................................................................................................................... 26

10.5 Request for Extension........................................................................................................ 33

10.6 Incorporation by Reference................................................................................................ 35

10.7 Net or Gross MW Output................................................................................................... 39
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10.1 MONITORING AND COMPLIANCE

Comment 10.1-1: Multiple commenters (0161, 0171, 0212, 0213, 0257) provided comments on 

the proposed monitoring requirements. Commenter 0213 noted that EPA currently requires 

covered units that burn solid fuel to install CEMS, but permits sources that burn exclusively

gaseous or liquid fuel to estimate their emissions based on fuel consumption data. The 

commenter suggested the Agency should instead require all sources to install CEMS, which the 

commenter said are inexpensive, readily available, and considerably more accurate than inputbased emission estimates. Moreover, regardless of its emissions monitoring system or method, 

each source must be required to include emissions during ramping and low-load periods in its 

data collection. These periods normally include higher emissions, and there is no legal or policy

rationale from excluding them from a compliance determination. 

Commenter 0171 stated that EPA should not require the use of stack flow monitors and CO2

analyzers, and should allow for additional monitoring options, including fuel flow meters. For 

example, NSPS proposed section 60.5525(c)(1) cross references 40 CFR 75.10(a)(3)(i), which 

would require the use of a stack flow monitor and would exclude other options, including fuel 

flow meters, that are provided within other provisions of 40 CFR 75.10(a)(3). The commenter 

said EPA should update this and any other references to make clear that all of the monitoring 

options provided within 40 CFR 75.10(a)(3) are available. There is no rational basis for EPA to 

limit monitoring options to stack flow monitors to the exclusion of fuel flow meters. Fuel flow 

metering under 40 CFR 75 is widely utilized and provides high quality CO2 emissions data. 

There is no rational basis not to allow the use of proven technology to calculate CO2 mass 

emissions as provided in 40 CFR 75, including fuel flow meters.

Commenter 0212 supported fuel consumption monitoring as the preferred method of 

measurement for gas turbines, with CEMs being a widely-available alternative. Commenter 0257 

requested that EPA allow the option to use an O2 analyzer and Equation G-4 of Appendix G to 

calculate CO2 emissions for NGCC units.

Commenter 0161 noted that EPA is proposing that measurements of electricity output be 

measured using 0.2 class electricity metering instrumentation and calibration procedures. The 

commenter suggested that EPA modify the proposal such that measurements of electricity output 

can be measured using whatever metering instrumentation is used for billing purposes

Commenter 0215 does not understand why EPA has specifically required use of a CO2 CEMS 

(and not allowed use of an O2 CEMS to obtain CO2) at an EGU that does not use carbon 

separation. The commenter stated that both existing NSPS applicable to modified and 

reconstructed EGUs - Subparts Da and KKKK - allow use of either a CO2 concentration monitor 

or an O2 concentration monitor as the diluent monitor to calculate emissions in lbs per MMBtu, 

and Part 75 explicitly allows use of an O2 concentration monitor to measure CO2 concentration 

to obtain CO2 mass emissions. The commenter stated that there is no valid reason not to allow 

both types of monitoring systems under this rule for EGUs without carbon capture.
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Response 10.1-1: The final rule (Subpart TTTT) allows the use of data from a certified O2

monitor to calculate hourly CO2 concentrations, provided that the affected EGU does not use 

carbon separation. The final rule requires the use of CEMS for coal-fired EGUs and IGCC units 

and allows all other affected units to use CEMS. However, units that combust only liquid and/or 

gaseous fuel may opt to use Equation G-4 in Appendix G of Part 75 to quantify the CO2 mass 

emission rate. Additionally, the EPA disagrees with the commenters that only a billing meter 

should be used for monitoring electricity output. The EPA is requiring the ANSI C12.20 class 

metering in the final rule to make sure all output measurements are consistent and comparable.

Comment 10.1-2: Commenters 0215 and 0257 submitted a comment on the proposed 

requirement for "EGU owners or operators to prepare and submit a monitoring plan that includes 

both electronic and hard copy components, in accordance with 40 CFR 75.53(g) and (h)."1 The 

commenter requested that EPA make clear that that the submission of a plan by a Designated 

Representative (DR) meeting part 75 also constitutes compliance with the NSPS requirements. 

Since monitoring plans under part 75 must be certified by a DR meeting the definition and 

requirements in Part 72, and information reported under an NSPS must be submitted by the 

facility owner or operator, which may be someone other than the DR, EPA must make 

allowances for the different certifications in these reporting systems. 

Commenter 0215 did not oppose a requirement in this rule for preparation of a monitoring plan 

for systems to measure and record CO2 mass emissions, or submission of that plan to ECMPS 

and the EPA regional office. The commenter stated, however, that the proposed rule language is 

overly broad in that the monitoring plan requirements in section 75.53(g) and (h) are not limited 

to monitoring systems for CO2 mass emissions.

Response 10.1-2: The EPA has clarified in the final rule that the submittals by the DR are 

required for compliance, additionally, the EPA has finalized clarifying language with respect to 

the monitoring plan submittals do not need to be in duplicate if the EGU has already submitted 

one.

Comment 10.1-3: Commenter 0215 stated that EPA says that it is proposing to require that all 

"monitoring systems" used to determine CO2 mass emissions be certified within the timeframe in 

40 C.F.R. section 75.4(b). The commenter stated that modified and reconstructed EGUs 

presumably already would have been generating electricity for sale and already would have had 

certified CO2 monitoring systems under Part 75. The commenter stated that if EPA intends that 

the deadline apply based on commencement of commercial operation following the modification 

or reconstruction, EPA should say that. The commenter stated that EPA also should make clear 

that new certification or diagnostic tests are not required for previously certified CO2 mass 

emissions monitoring systems except as provided in section 75.20(b).

Response 10.1-3: If a unit has a certified monitor in place, monitoring has to begin immediately. 

These requirements are consistent with the reference to part 75 in the final rulemaking.

Comment 10.1-4: Multiple commenters (0171, 0192, 0213, 0257) provided comments on the 

proposed CEMS certification and QA procedures. The proposed rule would require "all 

monitoring systems used to determine the CO2 mass emission rates...to be certified according to 

section 75.20 and section 6 of part 75, Appendix A within the 180-day window of time allotted 
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under section 75.4(b), and...meet the applicable on-going quality assurance procedures in 

Appendices B and D to part 75." Commenter 0192 argued that EPA must include provisions to 

address facilities that cannot meet CEMS certification requirements. The commenter was 

concerned that EPA's proposed requirements for monitoring and compliance determination 

procedures did not account for challenges that certain industry members have faced regarding 

CEMS for GHG emissions. While the majority of facilities that have installed CEMS systems 

have been able to certify them successfully, several have been unable to comply with the 20% 

variability range for flow RATA that EPA currently requires for CEMS certification. The 

commenter urged EPA to include an additional provision in the Monitoring and Compliance 

Determination Procedures section that would apply in lieu of the certification requirements in the 

event that, due to unforeseen circumstances, a source is unable to obtain CEMS certification. For 

example, EPA could permit such sources to comply with 40 CFR part 75 Appendix G, which 

includes a procedure for estimating CO2 emissions from combustion. 

Commenter 0213 stated that EPA should grant a 90-day rather than 180-day window in which to 

certify the performance of its CEMS. The shorter time period would ensure compliance sooner, 

would be consistent with EPA's initial timetable for certification of CO2 CEMS,3 and would 

reflect the time reasonably necessary to conduct the required procedures.

Commenter 0257 requested that EPA provide an explicit exemption from section 60.13(a) and 

Appendices B and F QA/QC requirements for sources using CEMS when following the QA 

standards of part 75 Appendices A and B.

Commenter 0171 requested that EPA not alter the daily calibration and relative accuracy

specifications currently provided in 40 CFR part 75. The justification for incorporating the 

monitoring methodologies of 40 CFR part 75, but altering daily calibration and relative accuracy

specifications is unclear. Moreover, such a change would result in unnecessary duplication; 

rendering what should be valid data for both the purposes of 40 CFR part 75 and the GHG 

NSPS, valid for one and not the other. Certain monitoring methods also have physical limitations 

that would make achieving these unnecessary standards likely impossible.

Commenter 0171 understood EPA's desire to solicit comment to ensure that monitoring 

standards are kept current over time, but argued that EPA offered no rationale or evidence to 

support the need to increase the stringency of existing CEMS regulations now in use under either 

40 CFR part 60 or 40 CFR part 75. EPA must take into account the fact that potential changes to 

these standards will place significant additional burdens on regulated entities without providing a 

commensurate additional benefits required by the President's recent executive order on 

Improving Regulation and Regulatory Review. As mandated by the executive order, EPA must 

ensure that it tailors its regulations to utilize "the least burdensome tools for achieving regulatory

ends" and "improve the actual result of the regulatory requirements," and regulations must be 

"based on the best available science."

Commenter 0215 supported the proposed reliance on Part 75 QA/QC. The commenter stated that 

to ensure that EGUs are not subject to duplicative and inconsistent QA/QC requirements, EPA 

must exempt EGUs using CEMS from the requirement in section 60.13(a) to comply with 

performance specifications in Part 60, Appendix B and ongoing QA/QC under Part 60, Appendix 
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F. The commenter stated that Part 60 Appendices B and F contain performance specifications 

and testing requirements that are duplicate and are inconsistent with the Part 75 QA/QC. The 

commenter stated that if EPA wants CO2 mass emissions under this NSPS to be quality-assured 

according to Part 75, EPA must identify the QA/QC requirements in section 60.13(a) as not 

applicable in Table 1 to Subpart TTTT, and should explicitly state in the applicable rules that 

those requirements do not apply. The commenter stated that if there are specific elements of Part 

60, Appendices B and F that EPA believes should apply in lieu of Part 75, EPA should identify

them and solicit comment on that alternative approach. The commenter stated that it did not 

understand EPA's proposed reference to compliance with Part 75, Appendix D for units using 

CEMS. The commenter stated that EPA should replace the reference to Appendices B and D 

with "Appendices A and B."

Response 10.1-4: These comments have been responded to elsewhere in this final rule.

Comment 10.1-5: Commenter 0215 does not oppose requiring solid fuel-fired EGUs that 

employ carbon separation technology to use a CO2 CEMS and a stack flow monitoring system, 

or allowing other EGUs to use such systems. The commenter stated that an O2 CEMS cannot be 

used to obtain accurate CO2 measurement at the stack of an EGU that employs carbon separation 

because that calculation to convert O2 measured at the stack to CO2 relies on the use of F-factors 

and any equation that uses an F-factor will not provide accurate measurements downstream of 

any device that removes CO2 from the gas stream.

Response 10.1-5: The EPA thanks the commenters for their comment.

Comment 10.1-6: Commenter 0215 stated that the proposed language requiring EGUs that 

measure CO2 concentration on a dry basis to "install, certify, operate, maintain, and calibrate a 

continuous moisture monitoring system" under section 75.11(b), could be interpreted as 

eliminating the option in section 75.11(b)(1) to use appropriate default moisture values rather 

than installing and calibrating a monitoring device. The commenter stated that the Part 75 default 

moisture values for coal and wood were derived from EPA's evaluation of data in a 1999 

rulemaking in which the Agency determined that they were sufficiently conservative to ensure 

no under-reporting. The commenter stated that if EPA has a reason for eliminating the O2

monitoring and moisture default value options for either modified or reconstructed coal-fired 

EGUs or modified and reconstructed liquid and gas-fired EGUs, it must issue a rulemaking 

proposal identifying that reason. The commenter stated that because modified and reconstructed 

EGUs still will need to comply with the ARP, eliminating these options in the NSPS effectively 

eliminates them for NSPS units in Part 75.

Response 10.1-6: The final rule allows the fuel-specific moisture defaults in §75.11(b) to be 

used in lieu of continuously monitoring the stack gas moisture content.

Comment 10.1-7: Commenter 0213 noted that the proposal requires sources to supply valid data 

for at least 95 percent of their operating hours. The commenter said the Agency must specify that 

a failure to meet the 95 percent valid data requirement constitutes a violation of the rule's 

monitoring requirements and should assess sufficiently stringent penalties against sources that 

fall short of this threshold. For suggestions on different penalty structures, the commenter 

referred to their Comments on the New Source Standard.
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Commenter 0215 requested clarification of what constitutes "valid data", and requested that 

should be consistent with Part 75. Commenter 0215 stated that with respect to the proposed 95 

percent data availability requirement, although UARG believes that most CO2 monitoring 

systems would be able to meet that criterion that may not be the case if the Part 75 data 

validation provisions are used. The commenter stated that it does not believe it would be 

appropriate to invalidate data in a rule with a 95 percent data availability requirement without 

some alternative validation procedure. The commenter stated that EPA should either (1) make 

clear that data are not invalidated under this rule unless a performance test is failed (i.e., unless 

the monitoring system is "out-of-control"), and take into account in the ICR the developing and 

maintaining separate databases for the two rules, or (2) include a procedure to validate data that 

does not otherwise meet Part 75.

Response 10.1-7: The EPA is finalizing the requirement of the use of valid data in all 

calculations for compliance with an applicable emission standard and is retaining the 

requirement of 95% data availability. Additionally the EPA is not allowing in this final rule for 

the use of any substitute data as the EPA does not believe it is appropriate to use for complying 

with the rate-based emission standards put in place by the final rule. The EPA has added 

language in the final rule to make these requirements clear.

Comment 10.1-8: Commenter 0215 stated that EPA proposes that only operating hours in which 

"valid data" are collected by the monitoring systems for all required parameters (including data 

recorded during startup, shutdown, and malfunction) be used for compliance purposes. The 

commenter stated that in the preamble, EPA appears to equate valid data with data from a 

monitoring system that is not "out of control." The commenter stated that EPA proposes to 

require EGUs to obtain valid hourly values for a minimum of 95 percent of the operating hours 

in the applicable compliance period and also proposes to prohibit use of missing data substitution 

procedures. The commenter agrees that EGUs should not use Part 75 missing data procedures in 

calculating compliance, and states that missing data procedures can significantly overstate 

emissions and interfere with compliance demonstrations. The commenter agrees that backup 

monitoring systems under section 75.10(e) and section 75.20(d) should be allowed, but not 

required. The commenter stated that EPA already has adopted a definition of "out-of-control" 

under Subpart Da, and proposed a definition of "out-of-control" under Subpart KKKK, that are 

not consistent with the Part 75 definition. The commenter stated that in 2012, EPA without 

notice or opportunity for comment promulgated a definition of "out-of-control" in Subpart Da 

under which the "out-of-control" period begins and ends with the corresponding quadrant" of an 

hour instead of the corresponding clock hour. The commenter stated that because EPA did not 

propose the definition, UARG petitioned for reconsideration of it. The commenter stated that to 

the extent EPA intends to require validation of hourly data based on 15 minute periods, the 

purpose and practical implications of that requirement are not clear. With respect to daily tests, 

the commenter believes that it is very unlikely that the definition would result in any greater 

level of data availability than the Part 75 definition. The commenter stated that facilities subject 

to both Subpart Da and Part 75 would need to have systems in place to track the different data 

validation rules and determine how the data under each rule are affected. The commenter stated 

that if EPA finalizes the proposed definition in Subpart KKKK, the same would be true for that 

rule. The commenter stated that in the event that EPA implements this NSPS through revisions to 

Subparts Da and KKKK (rather than promulgate a new Subpart TTTT), EPA should take this 

opportunity to revise the definition of "out-of-control" in Subpart Da to be consistent with Part 
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75, and adopt a consistent definition in Subpart KKKK. The commenter stated that if EPA 

promulgates a new Subpart TTTT, EPA should simply defer to the Part 75 definition, rather than 

promulgate a new one. The commenter stated that even if EPA resolves the conflicting 

definitions of "out-of-control," the rule will require clarification with respect to its relationship to 

Part 75. The commenter stated that Part 75 includes additional provisions under which data that 

are not otherwise "out-of-control" may be invalid if certain types of changes are made to the 

monitoring system, or if a quality-assurance test is not conducted on-time. The commenter stated 

that EPA must be clear whether such data would be considered valid under this NSPS and, if 

they would, must take into account the fact that facilities would need to keep a database that is 

separate from Part 75 reported data in order to implement this proposed rule.

Response 10.1-8: The final rule includes a definition of “valid data”, which defers to the data 

validation criteria in Part 75. Section §60.5540(a)(1) also defines a “valid operating hour” as one 

in which: (1) “valid data” are obtained for all parameters that are used to calculate the CO2 mass 

emission rate (tons/hr); and (2) the corresponding gross output value is available. Part 75 

substitute data values are not considered to be valid data. Also, for the purposes of Subpart 

TTTT, an operating hour in which there is a full-scale exceedance for a parameter that is used to 

calculate the CO2 mass emission rate (tons/hr) is not considered to be a valid operating hour.

The final rule retains the 95 percent data availability requirement and ties it to the definition of 

“valid operating hours”. For units that operate frequently, at least 95 percent of the operating 

hours in each compliance period must be “valid operating hours”.

The rule includes a provision allowing the use of backup monitors, in accordance with 

§§75.10(e) and 75.20(d). 

Comment 10.1-9: Commenter 0215 stated that if valid data are collected during a process or 

emission control equipment malfunction, EPA proposes that the data be included in compliance 

calculations, regardless of whether such data were considered when setting the standard and the 

commenter objects to this requirement. The commenter stated that EPA must demonstrate that a 

proposed NSPS is achievable with adequately demonstrated control technology. The commenter 

stated that in some cases the collection of data necessary to establish a standard of performance 

that accounts for malfunctions may not be technologically or economically practicable and that 

would be the case with respect to the Proposed Standards for modified and reconstructed fossilfuel-fired utility boilers. The commenter stated that to the extent EPA reviewed any data that 

included some periods of malfunction, it apparently was not possible for EPA to determine the 

impact of those malfunctions on any individual unit's compliance. The commenter stated that 

EPA has not established that any of its Proposed Standards are achievable even under normal 

operating conditions, let alone achievable in the event of a malfunction. The commenter stated 

that while EPA suggests that its proposal is consistent with the recent decision by the U.S. Court 

of Appeals for the D.C. Circuit in Natural Res. Def. Council v. EPA that decision did not address 

EPA's obligation to consider malfunctions under section 111, but only established that the rule 

EPA had adopted was not lawful under section 112.

Response 10.1-9: EPA disagrees with this comment and has concluded that there are important 

differences in using malfunction data for setting a standard as opposed to compliance 

calculations. For setting standards, the EPA interprets CAA section 111 as not requiring 
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emissions that occur during periods of malfunction to be factored into development of CAA 

section 111 standards. Nothing in CAA section 111 or in case law requires that the EPA 

consider malfunctions when determining what standards of performance reflect the degree of 

emission limitation achievable through ‘‘the application of the best system of emission 

reduction’’ that the EPA determines is adequately demonstrated. While the EPA accounts for 

variability in setting emissions standards, nothing in section 111 requires the Agency to consider 

malfunctions as part of that analysis. A malfunction should not be treated in the same manner as 

the type of variation in performance that occurs during routine operations of a source. A 

malfunction is a failure of the source to perform in a “normal or usual manner” and no statutory

language compels EPA to consider such events in setting section 111 standards of performance. 

By contrast, EPA has concluded that emissions during malfunctions should be included in 

compliance calculations. EPA acknowledges that 40 CFR section 60.8 provides that emissions 

during malfunctions shall not be considered a violation of the applicable emission limit, unless 

otherwise specified in the applicable standard. As explained in the proposed action, however, 

EPA interprets the reasoning of the court in the D.C. Circuit’s decision in Sierra Club v. EPA to 

apply to NSPS under section 111. Thus, EPA has concluded that excluding malfunction 

emissions from compliance calculations and treating such emissions as exempt is impermissible 

in light of the requirements of the CAA and the reasoning of the court in Sierra Club v. EPA 

concerning the statutory requirement for continuously applicable emission limitations. 

Comment 10.1-10: Commenter 0213 noted that the modified/reconstructed proposal currently 

provides for monthly compliance determinations. The commenter urged the Agency to conduct 

daily compliance determinations instead, which would better effectuate the CAA's goal of 

deterring and remedying all emission exceedances and would ensure that sources come into 

compliance more swiftly with their emission limits. 

Response 10.1-10: The EPA disagrees with the commenter 9514 and compliance is to be 

assessed solely on the basis of whether the average CO2 emission rate over the specified 12-

operating month averaging period meets the standard. For more discussion on the 12-operating 

month compliance period please see section IV.C. of the preamble.

Comment 10.1-11: Commenter 0213 stated that EPA must adopt measures to guarantee nearterm compliance with the rule. Consistent with past practice, the Agency should require each 

affected unit to perform an initial compliance demonstration using prescribed reference test 

methods within six months of modifying.

Response 10.1-11: The final rule retains the exemption from performing initial performance 

stack tests. Because compliance with the emission standards is based on a 12-operating month 

average, it is not reasonable to hold the sources to these standards based on the results of a stack 

test. Over a long period of time, the CO2 mission rate will fluctuate and may exceed the 

numerical value of the standard at times. If a 3-hour emission test is performed during one of 

these incidents, it may appear that the EGU is out of compliance. But this is not necessarily so. 

Compliance is to be assessed solely on the basis of whether the average CO2 emission rate over 

the specified 12-operating month averaging period meets the standard. For more discussion on 

the 12-operating month compliance period please see section IV.C. of the preamble.
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Comment 10.1-12: Commenter 0257 noted that EPA is proposing the same monitoring 

requirements for modified and reconstructed units as it proposed for new units in January, 2014.

The commenter submitted extensive comments on the proposed monitoring provisions of the 

new source proposal and incorporated those comments into this rulemaking docket by reference. 

Response 10.1-12: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.1-13: Commenter 0215 supported reliance on the Acid Rain Program (Part 75) 

monitoring procedures but objected to overly broad or duplicative requirements. The commenter 

stated that EPA has provided no justification for requiring EGUs to perform monitoring that is 

different from, let alone more stringent than, Part 75 and has explicitly asserted in its proposed 

Information Collection Request ("ICR") that it has not proposed to do so. The commenter lists 

the monitoring and compliance options provided in Part 75 in detail along with the fraction of 

reporters that use each option.

The commenter stated that the proposed rule generally recognizes the adequacy of Part 75 data 

by proposing to allow use of two of the four options allowed under Part 75, and by requiring 

compliance with Part 75 quality assurance and quality control ("QA/QC") and reporting 

requirements. The commenter stated that the ICR assumes only a "minimal information 

collection burden" beyond what already is required under Part 75 and the Greenhouse Gas 

Reporting Rule. The commenter stated that EPA also in some instances proposes, or solicits 

comment on imposing new requirements that increase burden and stringency. The commenter 

supports reliance on Part 75 monitoring procedures, without bias adjustment or missing data 

substitution, but objects to the proposed elimination of one of the options and imposition of 

additional requirements for modified and reconstructed units. The commenter stated that EPA 

has provided no justification for requiring EGUs to perform monitoring that is different from and 

more stringent than, Part 75 and has explicitly asserted in its proposed ICR that it has not 

proposed to do so.

Response 10.1-13: The EPA has added detail at the request of the commenters that emissions 

monitoring under Subpart TTTT is to be done according to Part 75 where applicable. 

Additionally the EPA is not allowing in this final rule for the use of any substitute data as the 

EPA does not believe it is appropriate to use for complying with the rate-based emission 

standards put in place by the final rule.

Comment 10.1-14: Commenter 0215 requested inclusion of a procedure to obtain an exemption 

from demonstrating compliance for equipment that is not monitored by Pat 75 or an NSPS, or 

that alternate monitoring procedures be approved. The commenter stated that it was not a good 

use of resources to monitor equipment that operates infrequently and has low emissions.

Response 10.1-14: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.
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Comment 10.1-15: Commenter 0215 supported the provisions for monitoring "electric output," 

with two exceptions and with a few clarifications. The commenter stated that the value reported 

under Part 75 represents an hourly rate and not the total load for the hour. The commenter stated 

that for hours of partial operation, the value already reported under Part 75 will not represent the 

actual output for that hour. The commenter stated that, in addition, reported steam load for an 

hour is reported at the measured temperature and pressure (i.e., is not corrected to ISO 

conditions). The commenter stated that if EPA intends sources to include partial unit operating 

hours in compliance calculations, the values already being reported under Part 75 will need some 

adjustment for use in EPA's proposed compliance calculations. The commenter stated that if 

EPA wants those adjusted output values to be reported to ECMPS in addition to the values 

already reported under Part 75, EPA must include that requirement in the rule. The commenter 

stated that EPA also should clarify in the rule whether it intends that partial unit operating hours 

be included, and to the extent EPA does intend to include partial unit operating hours, it also 

must ensure that any data analysis it used to support its emission standard also included such 

hours.

Response 10.1-15: The final rule retains the requirement to use gross energy output in the 

compliance calculations in addition to allowing stationary combustion turbines with permit 

requirements to monitor net energy output. For partial operating hours, the gross MW values 

reported under Part 75 must be adjusted using the unit or stack operating time, to convert them to 

MWh. 

Comment 10.1-16: Commenter 0215 supported the proposal to allow liquid and gaseous fuelfired EGUs to use the Appendix G in lieu of CEMS, and the proposal to allow, but not require, 

the use of site-specific F-factors under equation G-4. The commenter stated that the variability in 

commonly used fuels is not sufficient to warrant determination of a site-specific F-factor for all 

fuels. The commenter stated that requiring development of a site-specific F-factor for commonly

used fuels would be a waste of time and resources, however, the option to develop such factors is 

necessary to account for the fact that EPA may not have developed a default factor for some 

fuels.

Response 10.1-16: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets

Comment 10.1-17: Commenter 0215 stated that EPA has not provided justification for the 

proposed requirement to comply with the American National Standards Institute ("ANSI") 2010 

C12.20 standard for electricity meters in this rulemaking, which they consider to be 

burdensome. The commenter stated that EPA has not provided any information to suggest that 

all EGUs are not already using meters of acceptable accuracy or that requiring compliance with 

the ANSI standard would not impose additional burdens or require the upgrading of equipment. 

The commenter stated that EPA has never before found it necessary to impose such requirements 

because EGUs already have sufficient incentives to ensure that the electricity they generate and 

use is accurately measured. The commenter stated that some EGUs may have meters that comply 

with all or parts of the ANSI standard, some do not and the cost of replacing such meters is not 

insignificant. The commenter stated that the ANSI standard itself is extraordinarily detailed and 

not at all suited to a regulatory program under which penalties could be sought for a failure to 
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comply. The commenter stated that if EPA establishes limits based on net electric output, EPA 

must allow EGUs to use existing equipment and methods for metering station service to make 

the required measurements, and to apply simple apportionment schemes based on unit generation 

where common station service must be allocated to individual units. The commenter stated that if 

EPA were to require replacement of existing equipment or to impose more stringent standards on 

existing equipment, EPA would need to revise its proposed ICR to estimate and solicit input on 

the additional costs and burdens.

Response 10.1-17: The EPA believes it is necessary to have standardized monitoring for sources

to measure the electric output from their facilities especially when sources are complying with 

output based standards. The fee to access the ANSI standard is nominal and should not be a 

barrier for this industry to evaluate the standard and additionally the commenter notes that many 

EGUs may have monitors that already meet this standard. Additionally, the EPA believes that 

any source undergoing modification or reconstruction will not have significant challenges in the 

instillation of monitors that meet the ANSI C12.20 standard. Therefore, in the final rule, EPA is 

requiring use of ANSI 0.2 class meters to measure and report electric generation.

Comment 10.1-18: Commenter 0215 questions EPA's focus on the accuracy of useful thermal 

output measurements given the Agency’s uncertainty regarding the amount of credit that should 

be provided for whatever is measured. The commenter stated that although EPA has proposed to 

allow credit for 75 percent of measured useful thermal output, it also has solicited comment on 

providing credit for as little as two-thirds and as much as 100 percent. The commenter stated that 

any accuracy gains that might be achieved from imposing additional requirements would be lost 

in the noise of the calculations and assumptions used to justify the arrived upon percent credit. 

The commenter stated that each EGU should be allowed to select the technologies that best suit 

its needs under the circumstances. The commenter stated that different types of meters, 

instruments, and calculation methods also provide varying levels of accuracy depending on the 

steam conditions, which can vary from source to source. The commenter stated that some 

equipment simply would not benefit from any periodic QA. The commenter stated that 

thermocouples and resistance temperature detectors (RTDs) either work or fail completely. The 

commenter stated that manufacturers' recommendations also are not universally appropriate for 

ongoing maintenance or QA, and are not appropriate for use in rules because they vary from 

vendor to vendor and can change over time. The commenter stated that performance test codes 

are not appropriate for ongoing QA because they were designed for performance testing, not 

long term performance, and although most flow meters probably would meet the ASME MFC 

standards EPA has not justified imposition of such standards in this context.

Response 10.1-18: Specific monitoring requirements for useful thermal output are not included 

in this final rule.

Comment 10.1-19: Commenter 0215 stated that EPA proposed a new requirement to measure 

the dimensions of each stack or duct at the flow monitor and reference method sampling location 

using a laser device. The commenter stated that the rulemaking record, however, contains no 

evidence that existing methods are not sufficiently accurate, and no evidence that laser devices 

would provide significantly more accurate results, and it appears that the requirement imposes 

additional cost and burden with no corresponding benefit. The commenter stated that if EPA has 

evidence to support this proposed requirement, EPA should provide it.
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Response 10.1-19: The EPA thanks the commenters for the comments and is finalizing the rule 

with the requirement to measure stack gas flow according to Appendix A or part 75 and 

§75.10(a)(3)(i). Additionally the EPA is finalizing measurements of diameter to be required at 

only 2 locations for circular stacks and 2 locations for each length and width of rectangular 

ducts.

Comment 10.1-20: Commenter 0215 supported EPA's decision not to solicit comment or 

propose to apply to modified or reconstructed units a number of additional measurement 

requirements which EPA solicited comment in its January 2014 proposal for new EGUs to 

"increase the precision of GHG measurements."

Response 10.1-20: The EPA thanks the commenter for their comments

Comment 10.1-21: Commenter 0215 stated that the rule should allow EGUs to report (and 

include in compliance calculations) a value of 1 or 2 MW for any hour during which monitored 

gross load is zero.

Response 10.1-21: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking docket.

Comment 10.1-22: Commenter 0215 stated that if EPA establishes limits based on net electric 

output, EPA must allow EGUs to use existing equipment and methods for metering station 

service to make the required measurements and to apply simple apportionment schemes based on 

unit generation where common station service must be allocated to individual units.

Response 10.1-22: The final rule allows for both compliance with a gross standard and net 

standard (if required in an applicable permit for affected stationary combustion turbines) and the 

combined gross electrical load to be apportioned to the individual EGUs based on the fraction of 

the total steam load contributed by each unit. If the units are identical, the combined hourly gross 

electrical load may be apportioned to the individual EGUs according to the fraction of the total 

heat input contributed by each unit.

Comment 10.1-23: Commenter 0215 stated that combined heat and power ("CHP") facilities 

should not be required to employ any specific technology or quality assurance ("QA") 

procedures for equipment used to measure useful thermal output because any gains in accuracy

from employing a specific technology or procedure would likely would be insignificant relative 

to other uncertainties in the calculation of creditable output.

Response 10.1-23: The EPA is requiring all monitoring to be consistent with part 75 provisions.

Comment 10.1-24: Commenter 0215 requested clarification of the intent of the proposed 

monitoring system certification requirements for modified and reconstructed units.

Response 10.1-24: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets
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Comment 10.1-25: Commenter 0215 stated that when EPA proposed to include "integrated 

combustion turbines and fuel cells" in the definition of a post-May 3, 2011 steam generating unit 

in Subpart Da, EPA recognized that emissions from that equipment likely would not be 

exhausted through the primary boiler stack and, because the emissions would be relatively small, 

suggested that they be estimated rather than monitored. The commenter believes that there are 

few real world application ns for such equipment, at least at fossil-fuel-fired utility boilers but if 

such equipment were used, continuous monitoring likely would not be warranted. The 

commenter suggested that EPA include a provision allowing submission and approval of a 

petition for exemption of emissions that are deminimis from the compliance calculation, or for 

an alternative means of accounting for any resulting emissions (e.g., a mass balance calculation 

or engineering estimate) from any integrated equipment that is not otherwise required to be 

monitored under an NSPS or otherwise accounted for in the primary equipment's monitoring 

(e.g., by venting the emissions into a stack with CEMS).

Response 10.1-25: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets

10.2 RECORDKEEPING

Comment 10.2-1: Commenter 0215 stated that EPA proposes a number of recordkeeping 

provisions, some of which are overly broad, unnecessary, and in conflict with other provisions. 

As a result, the commenter objects to them. The commenter also opposes any recordkeeping 

requirement that duplicates Part 75. The commenter stated that EPA proposes to require 

compliance with all applicable Part 75 recordkeeping requirements. Proposed Applicability Text, 

Subpart TTTT section 60.5560(b)-(d), Subpart Da section 60.46Da(i)(1), Subpart KKKK section 

60.4391(b). UARG agrees that EGUs relying on Part 75 methods for monitoring CO2 mass 

emissions should comply with Part 75 recordkeeping for those methods. However, as noted 

above, the commenter opposes any recordkeeping requirement that duplicates Part 75.

Response 10.2-1: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets

Comment 10.2-2: Commenter 0213 stated that EPA must require that sources maintain on-site, 

and make readily available at all times, their records of emission data. The current proposal 

would permit sources to move records off-site after two years, but this provision would not 

advance any policy-based goals and would add unnecessary burdens to EPA or state-based 

enforcement investigations.

Response 10.2-2: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.2-3: Commenter requested EPA include a provision in the rule allowing EGUs 

to include in compliance calculations a value of 1 MW for any hour during which monitored 

gross load is zero or for hours with gross generation less than auxiliary loads.
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Response 10.2-3: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.2-4: EPA is proposing the same recordkeeping requirements for modified and 

reconstructed units as it proposed for new units in January, 2014. Commenter 0257 submitted 

extensive comments on the proposed recordkeeping provisions of the new source 

proposal and incorporated those comments into this rulemaking docket by reference.

Response 10.2-4: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.2-5: Commenter 0215 opposed the proposed five-year record retention period for 

all of the supporting information for the 12-operating-month rolling average standard, unless 

EPA can show a special need as required under the Paperwork Reduction Act regulations. The 

commenter also opposed the proposed on-site requirement if it means that retention of electronic 

records that can be accessed "onsite" (even if they are physically located offsite) would not be 

sufficient. 

The commenter also stated that EPA proposes to require retention of records for 5 years from 

occurrence, except that for EGUs complying with the 84-operating month average option EPA 

proposes to require retention for 10 years. Proposed Applicability Text, Subpart TTTT section 

60.5565(b), Subpart Da section 60.46Da(i)(7), Subpart KKKK section 60.4391(h)(2). For the 

first 2 years, EPA proposes that the records must be retained onsite. Id., Subpart TTTT section 

60.5565(c), Subpart Da section 60.46Da(i)(8), Subpart KKKK section 60.4391(h)(3) 

The commenter opposes the proposed 5 year record retention period for all of the supporting 

information for the 12-operating-month rolling average standard, unless EPA can show a special 

need as required under the Paperwork Reduction Act regulations. 5 C.F.R. section 

1320.5(d)(2)(iv). To the extent EPA intends to audit the accuracy of a certified report by 

reference to supporting information, EPA should do so within a reasonable period of time (e.g., 3 

years). Absent an audit, the data have little or no usefulness. Part 75 has a 3-year record retention 

requirement and EPA has not provided any information to suggest that has been inadequate. 40 

C.F.R. section 75.57(a). UARG also opposes the proposed on-site requirement if it means that 

retention of electronic records that can be accessed "onsite" (even if they are physically located 

offsite) would not be sufficient. Many of the records EPA requires be retained are recorded only 

in electronic form and, depending upon the facility's management practices, may be retained at a 

central location in order to facilitate backups and other services. As long as the facility can 

access the information onsite, there is no reason for it to be physically located there.

Response 10.2-5: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets

Comment 10.2-6: Commenter 0215 stated that EPA proposes a number or recordkeeping 

provisions. First, EPA proposes to require maintenance of records specified in section 60.7(b) 
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and (f). Proposed Applicability Text, Subpart TTTT section 60.5560(a), Subpart KKKK section 

60.4391(a). These provisions require (1) recording of the occurrence and duration of startup, 

shutdown, and malfunction periods and periods when monitoring systems are inoperative, and 

(2) with respect to monitoring systems, recording and retention for two years of all 

measurements, quality assurance test results, adjustments, and maintenance. The commenter 

stated that these provisions are overly broad, unnecessary, and in conflict with other provisions. 

With respect to startups and shutdowns, given that there are no provisions in the proposed NSPS 

that apply only to startup or shutdown, there is no basis to require records of those periods in this 

rule. And, the other information addressed in these provisions already is required to be recorded 

under Part 75, compliance with which also is required under this rule. Presumably, it is for these 

reasons that Subpart TTTT, Table 3 limits applicability of section 60.7 to the notification 

requirements in (a)(1) and (a)(3). In light of these duplications and inconsistencies, EPA should 

remove this subsection.

Response 10.2-6: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.2-7: Commenter 0215 stated that EPA proposes to require recording of 

calculations performed to determine (1) total CO2 mass emissions "each operating month," and 

"each compliance period," (2) gross output for "each operating month," (3) percent valid CO2

rates each compliance period, (4) compliance with each applicable CO2 standard, and (5) any 

site-specific carbon-based F-factors used. Proposed Applicability Text, Subpart TTTT section 

60.5560(c)-(g), Subpart Da section 60.46Da(i)(2)-(5), Subpart KKKK section 60.4391(c)-

(g). The commenter does not oppose keeping records of calculations of CO2 mass emissions and 

gross output for each "compliance period," calculations of percent valid CO2 mass emissions, or 

calculations to assess compliance. However, because there is no requirement to calculate CO2

mass emissions or gross output for "each operating month," there is no basis to require recording 

of such calculations. CO2 mass and gross output emissions may be calculated at the end of each 

operating month, but the value calculated is the total mass emissions and total gross output over 

the entire compliance period, and not for the operating month. EPA should remove the 

provisions that refer to operating months.

Response 10.2-7: The EPA has clarified the recordkeeping requirements in the final rule.

10.3 REPORTING

Comment 10.3-1: Commenter 0257 requested EPA include a provision in the rule allowing 

EGUs to report a value of 1 MW for any hour during which monitored gross load is zero or for 

hours with gross generation less than auxiliary loads.

Response 10.3-1: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.3-2: EPA is proposing the same reporting requirements for modified and 

reconstructed units as it proposed for new units in January, 2014. Commenter 0257 submitted 
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extensive comments on the proposed reporting provisions of the new source proposal

and incorporated those comments into this rulemaking docket by reference. 

Response 10.3-2: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.3-3: Commenter 0215 stated that they support the language in the Proposed 

Standards under which quarterly reporting would not be required until there is a compliance 

value ready to report. Because the data necessary to calculate compliance already are reported 

under Part 75, there is no reason to require reporting under this rule until the end of the first 

compliance period. For the first compliance period, EPA must ensure that a full operating month 

is included.

The commenter stated that EPA's proposal to require compliance with "all applicable" reporting 

requirements in Part 75 is reasonable, but the wording is overly broad and could be 

misconstrued. Proposed Applicability Text, Subpart TTTT section 60.5555(c), Subpart Da 

section 60.46Da(h)(4), Subpart KKKK section 60.4376(d). If read literally, any deficiency in 

reporting under Part 75 would be a violation of this proposed rule even if it was completely 

unrelated to this NSPS. EPA should reword this provision to explain that "applicable reporting 

requirements" means reporting of information needed to calculate lb CO2/MWh - i.e., hourly

load and any information used to calculate CO2 mass emissions.

Response 10.3-3: The he EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.3-4: Commenter 0215 stated that they support the proposal to rely on monitoring 

already performed and hourly data already reported under Part 75 to demonstrate compliance as 

long as the data used do not include missing data substitution or bias correction factors. 

However, the commenter would object to any attempt by EPA to use ECMPS to require 

reporting of any information, codes, calculations, or other information that is not identified both 

in the rule and in an ICR approved by OMB. If EPA believes that any additional information 

must be reported to ECMPS to demonstrate compliance with this proposed NSPS, EPA must 

issue a rulemaking proposal identifying the information and the need for it, and soliciting 

comment on that proposal. UARG also would object to any attempt by EPA to use electronic 

auditing software within ECMPS to impose on reporting facilities any requirements or quality 

assurance criteria that are not identified in the rule. The commenter stated that EPA also must 

ensure that the new information required to be submitted by the rule is separately identified in 

the ECMPS quarterly report and that a mechanism is provided for the facility's owner or operator 

(or his/her agent) to review and, where the rule requires, certify the accuracy of the new 

information. As EPA is aware, under 40 C.F.R. section 72.21(b)(2), each submission under Part 

75 related to the ARP must be certified as "true, accurate, and complete" by the facility's DR. 

Under 40 C.F.R. section 75.64(c), the DR also must make certain certifications in support of 

each "quarterly emissions monitoring report." Under 40 C.F.R. section 72.2, the DR is defined as 

a person authorized by the owners and operators of an affected source (and all affected units at 

the source) as evidenced by a "certificate of representation" to represent and legally bind each 
10-17

owner and operator. As a result, those data elements in ECMPS that are required to be reported 

under Part 75 must be certified by a person meeting that definition of DR. 55

Response 10.3-4: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.3-5: Commenter 0215 stated that they do not oppose the notification requirements 

of submission of notices under 60.7(a)(1) (construction date) and (3) (initial startup date), section 

60.19 (general provisions regarding time periods, postmarks, etc.), and in section 75.61 

(submittal of test notifications, notification of commercial operation, notification of certification 

deadline, etc., to the appropriate EPA Regional Office and state). However, the commenter stated 

that EPA should exempt the notices in section 75.61 from the duplicate reporting requirements in 

section 60.4(a) and (b), which require that "[a]ll requests, reports, applications, submittals, and 

other communications to the Administrator pursuant to this part" be submitted "in duplicate" to 

the appropriate EPA Regional Office and to any delegated state. Because section 75.61 already 

requires submission to those officials, there is no basis for requiring additional reporting "in 

duplicate" under Part 60.

The commenter supported EPA's proposal to exempt facilities from compliance with section 

60.7(c) with respect to Subpart TTTT. Part 75 already requires reporting of the status of the 

relevant monitoring systems, and EPA has proposed new requirements for reporting of percent 

valid data and excess emissions periods. If EPA proceeds with implementation of this NSPS 

through revisions to Subparts Da and KKKK, EPA will need to include in those revisions an 

explicit exemption from section 60.7(c) in order to avoid those duplicative reporting 

requirements.

Regardless of how it is implemented (i.e., through Subpart TTTT or Subparts Da and KKKK), 

the commenter stated that EPA must exempt all of the electronic reporting requirements in the 

NSPS from section 60.4. If read literally, section 60.4 would require facilities to extract from the 

current Part 75 electronic quarterly reports all of the information required to be reported under 

this NSPS and then create and submit in duplicate a totally new report to EPA Regional Offices 

and states. Such a requirement clearly is not contemplated by this proposal and would not be 

reasonable. EPA should foreclose any such unreasonable reading of this requirement by

including an explicit exemption from section 60.4 for any information reported to ECMPS. If 

EPA Regional Offices or states want the information, they can obtain it from the CAMD. If EPA 

believes that facilities should report this information directly to EPA Regional Offices and to 

states, EPA will need to propose a new rule that does not rely on or require reporting to ECMPS.

Response 10.3-5: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

10.4 REGULATORY TEXT

Comment 10.4-1: Multiple commenters (0176, 0192, 0247, 0260) noted that EPA did not 

include proposed regulatory text in the Federal Register notice for the NSPS for 
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modified/reconstructed sources. Commenter 0260 argued that this is a violation of EPA's duty to 

provide adequate notice of the proposed rulemaking under section 307 of the CAA. See 42 

U.S.C. 7607(d)(3). 

Commenters 0192 and 0247 noted that EPA directed commenters to a technical support 

document in the docket to find the language that EPA was proposing to adopt. However, EPA 

issued two documents that contain significantly different regulatory language--a "proposed 

applicability" version and "broad applicability" version. The documents show revisions to the 

regulatory text in the January 2014 proposal of the NSPS for new sources. Commenter 0260 

argued that including the proposed regulatory text in the docket does not correct the error of not 

providing adequate notice of the proposed rulemaking. According to commenter 0247, there is 

no explanation in the docket of which of these two documents commenters should be reviewing 

and why. Commenter 0247 also noted that the phrase "broad applicability" used in one of the 

documents is not used in the preamble to the proposed rule, which would have provided some 

context to help commenters understand how those memoranda were used in the proposal.

Commenter 0192 stated that, because neither document is specifically referenced in the proposed 

rule, it is unclear what sources EPA is proposing to regulate in this proposal. Even more 

troubling, the "broad applicability" version would remove virtually all of the applicability 

thresholds included in the January 2014 proposal and instead use them to create what appears to 

be a new subcategory of sources to which no numeric emission standard is applied. However, 

such sources would still be considered "affected EGUs" and would, therefore, be subject to 

certain monitoring, recordkeeping, and reporting obligations, even if no numeric standard of 

performance applied. Further, by removing applicability criteria related to a source's intended 

purpose at the time of construction, the broad applicability version would create a risk that 

facilities could become subject to numeric standards of performance long after construction, 

modification, or reconstruction as a result of unforeseen changed circumstances. To avoid the 

risk and confusion associated with EPA's approach, commenter 0192 urged EPA to withdraw the 

rules and publish a single proposal in the Federal Register that includes--subject to their other 

comments--all of the applicability criteria from the January 2014 proposal for newly constructed 

sources.

Response 10.4-1: EPA disagrees that commenters did not have adequate information to allow 

them to comment on the various options for regulatory text.

Comment 10.4-2: Commenter 0176 noted that EPA asked for additional approaches to address 

potential unintended environmental impacts from regulating NGSC units as proposed. If EPA 

does not exclude NGSC in the final NSPS, then commenter 0176 suggested that EPA revise the 

applicability section in a manner set forth below. The suggested revisions would address the 

unintended environmental consequences of the proposed rule arising from its potential to limit 

quick start NGSC usage needed for grid reliability. The commenter proposed adding new 

subsections (6) and (7) as follows to the applicability section in the proposed new unit NSPS in 

section 60.4305(c) and asked for the same corresponding change to the modified unit NSPS: 

(c) For purposes of regulation of greenhouse gases, the applicable provisions of this subpart 

affect your stationary combustion turbine if it meets the applicability conditions in paragraphs 

(c)(1) through (c)(7) of this section. . . .
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(6) Does not meet both of the following requirements: (1) is capable of injecting 75% of total 

generation unit nameplate capacity into the grid from a shutdown state, within 15 minutes of a 

dispatch directive from the dispatching Independent System Operator (ISO) or balancing 

authority, and (2) is capable of completing a minimum of two Startup/Shutdown cycles within a 

24 hour period; and

(7) Does not participate as a Market Dispatched Generation Resource (MDGR), or the stationary

combustion turbine is not within a Balancing Authority where combustion turbines support 

reliability of the grid and where dispatch is controlled by a local Balancing Authority that is not 

under the control of the stationary combustor owner or operator.

Commenter 0176 acknowledged that EPA is considering and taking comment on changing the 

"one third potential electric output" sales criteria to "the design net efficiency times the potential 

electric output" for simple cycle combustion turbines. See 79 FR 34980. EPA believes this 

would have the effect of allowing NGSC to sell 38% of their electric output before the emission 

standard would apply. The commenter did not support this change and provided language in their 

comments that would address the problematic impacts that are associated with requiring the 

installation of HRSG units that would limit the quick start capabilities of NGSC units as set forth 

herein. NGSC units play and will continue to play a critical role to support renewables energy

and this option being considered by EPA would still result in the adverse impacts described 

above.

Commenter 0176 stated that these new applicability sections would allow NGSC units to operate 

in ways that support renewables and grid reliability and avoid the unintended consequence of 

increasing overall emissions and reducing wind generation.

The commenter argued that adding section 60.4305(c)(6) would ensure that only those NGSC 

units with quick start capabilities would be excluded. As stated in the testimony of Mr. Hess of 

their company in Attachment 2 of their comment, recent advancements in NGSC technology

have reduced start-up time to as little as 70% of maximum output in approximately 10 minutes 

and full power in approximately eleven minutes on some NGSC units. As further stated in the 

Affidavit of Mr. Nickell of the SPP (in Attachment 1 of their comment), this fast start capability

makes NGSC uniquely suited to back up intermittent wind generation. Section 111(b) of the 

Clean Air Act promotes this new technological improvement in NGSC. As discussed in the 

proposed rule, expanded use and development of technology is one of the factors EPA must 

consider when determining BSER. Based on legislative history, the EPA identifies three different 

ways that Congress designed CAA section 111 to authorize standards of performance that 

promote technological improvement: (i) the development of technology that may be treated as 

the "best system of emission reduction . . . adequately demonstrated"; under section 111(a)(1); 

(ii) the expanded use of the best demonstrated technology; and (iii) the development of emerging 

technology. Because NGSC units, in conjunction with renewable energy can provide "virtual 

base load generation" that will benefit grid reliability for this growing renewable energy

resource, the commenter believes that these changes to the applicability section are also 

consistent with the "technology forcing" nature of section 111(b).
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The commenter argued that adding section 60.4305(c)(7) and the definition for MDGR and 

Balancing Authority would also ensure that economics will control the dispatch of NGSC units. 

Those units that are excluded will only be those that are dispatched by the market or Balancing 

Authority, and not those dispatched by the NGSC unit owner or operator. The commenter was 

aware that EPA is concerned that NGSC owners not be in a position to "game the system." 

Limiting the exemption to situations where a central ISO or Balancing Authority controls the 

dispatch of generation assures that NGSC owners cannot dispatch units where those units are not 

either economical or needed for system reliability, including where units may be needed to 

maximize utilization of renewable generation with the potential to reduce overall CO2 emissions. 

As Mr. Nickell of SPP stated in his affidavit, due to increased operating costs, NGSC units are 

and will continue to be the last to be dispatched unless there is a good reason to dispatch them

out-of-merit for support of grid reliability (i.e., to support variable wind due to their fast start 

capability upon notification, as discussed above.). In addition, since the implementation of the 

SPP Integrated Marketplace, SPP's dispatch mix has experienced an increase in the dispatch of 

NGSC units and an increase in an output of wind generation from 2013 to 2014. Commenter 

attached an affidavit of Mr. Lanny D. Nickell, SPP, and a testimony of Mr. Tom Burke, Golden 

Spread.

Response 10.4-2: The EPA has added detail in the applicability sections of the rule and clarified 

what applicable monitoring and recordkeeping EGUs have to do depending on what standard is 

applicable to them. The final rule has an operational element for an EGU to determine what 

emission standard is applicable and for more discussion on this topic see sections VIII.C. and 

IX.A.3 of the preamble.

Comment 10.4-3: Commenter 0192 suggested that EPA consider revising the applicability 

criteria for affected sources to exclude CHP units from the industrial and manufacturing sectors 

and proposed that EPA accomplish this exclusion by adopting the following text for sections 

60.46(a), 60.4305(c) and 60.5509(a)(3): 

Section 60.46Da Standards for carbon dioxide (CO2).

(a) Your affected facility is subject to this section if it meets the conditions specified in 

paragraphs (a)(1) or (a)(2) of this section, except as specified in paragraph (b) of this section.

(1) Construction commenced after January 8, 2014 and meets the conditions specified in 

paragraphs (a)(1)(i), (a)(1)(ii), and (a)(1)(iii) of this section.

(i) The affected facility was constructed for the purpose of supplying more than 60% of its gross 

energy output as net-electric sales to a utility distribution system on a 3-year rolling average 

basis;

(ii) The affected facility combusts fossil fuel for more than 10% of the heat input during any 3 

consecutive calendar years; and

(iii) The affected facility supplies more than 60% of its gross energy output as net-electric sales 

to a utility distribution system on a 3-year rolling average basis.
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(2) Modification or reconstruction commenced after June 18, 2014 and meets the conditions 

specified in paragraphs (a)(2)(i), (a)(2)(ii), and (a)(2)(iii) of this section.

(i) The affected facility was constructed for the purpose of supplying more than 60% of its gross 

energy output as net-electric sales to a utility distribution system on a 3-year rolling average 

basis;

(ii) The affected facility combusts fossil fuel for more than 10% of the heat input during any 3 

consecutive calendar years; and

(iii) The affected facility supplies more than 60% of its gross energy output as net-electric sales 

to a utility distribution system on a 3-year rolling average basis. 

Section 60.4305 Does this subpart apply to my stationary combustion turbine?

(c) For purposes of regulation of greenhouse gases, the applicable provisions of this subpart 

affect your stationary combustion turbine if it meets the applicability conditions in paragraphs 

(c)(1) through (c)(5) of this section.

(1) Commenced construction after January 8, 2014 or it commenced reconstruction or 

modification after June 18, 2014;

(2) Has a design heat input to the turbine engine greater than 73 MW (250 MMBtu/h);

(3) Combusts fossil fuel for more than 10% of the heat input during any 3 consecutive calendar 

years.

(4) Combusts over 90% natural gas on a heat input basis on a 3-year rolling average basis; and

(5) Was constructed for the purpose of supplying, and supplies, more than 60% of its gross 

energy output as net-electric sales to a utility distribution system on a 3-year rolling average 

basis. 

Section 60.5509 Am I subject to this subpart?

(a) Except as provided for in paragraph (b) of this section, the subpart applies to any steam 

generating unit, IGCC, or stationary combustion turbine that commenced construction after 

January 8, 2014 or commenced modification or reconstruction after June 18, 2014 that meets the 

relevant applicability conditions in paragraphs (a)(1), and (a)(2), or (a)(3) of this section.

(1) A steam generating unit or IGCC that commenced construction after January 8, 2014 and has 

a base load rating greater than 73 MW (250 MMBtu/h) heat input of fossil fuel (either alone or in 

combination with any other fuel), was constructed for the purpose of supplying, and supplies 

more than 60% of its gross energy output as net-electric sales to a utility distribution system on a 

3-year rolling average basis, and combusts fossil fuel for more than 10.0 percent of the heat input 

during a 3 year rolling average basis.
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(2) A steam generating unit or IGCC that commenced modification or reconstruction after June 

18, 2014 and has a base load rating greater than 73 MW (250MMBtu/h) heat input of fossil fuel 

(either alone or in combination with any other fuel); was constructed for the purpose of 

supplying, and supplies more than 60% of its gross energy output as net-electric sales to a utility

distribution system on a 3-year rolling average basis; and combusts fossil fuel for more than 10% 

of the heat input during a 3 year rolling average basis.

(3) A stationary combustion turbine that has a base load rating greater than 73 MW (250 

MMBtu/h); was constructed for the purpose of supplying, and supplies more than 60% of its 

gross energy output as net-electric sales to a utility distribution system on a 3-year rolling 

average basis; combusts fossil fuel for more than 10% of the average annual heat input during a 

3-year rolling average basis; and combusts over 90% natural gas on a heat input basis on a 3-year 

rolling average basis.

Response 10.4-3: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.4-4: Commenter 0215 noted that in Subpart Da, EPA describes the proposed 

standard for large reconstructed and modified units of 1,900 lb CO2/MWh as equivalent to 820 

kg CO2/MWh of net energy output. Proposed Applicability Text, Subpart Da Section

60.46Da(c)(2)(ii) and (3)(i)(C). However, in Subpart TTTT, EPA describes the same standard as 

equivalent to 860 kg CO2/MWh of net energy output. Proposed Applicability Text, Subpart 

TTTT, Table 2. In Subpart KKKK, EPA describes the 1,000 lb/MWh standard for large NGCC 

units as equivalent to 450 kg CO2/MWh of gross output and the 1,100 lb/MWh standard for 

small NGCC units as equivalent to 500 kg CO2/MWh of gross output. Proposed Applicability

Text, Subpart KKKK, Tbl. 2. However, in Subpart TTTT, EPA describes those same standards 

as equivalent to 460 kg CO2/MWh of gross output and 510 kg CO2/MWh of gross output, 

respectively. Proposed Applicability Text, Subpart TTTT, Tables 1 and 2. The 

commenter believes that the Subpart TTTT standards for boilers and IGCC units and the Subpart 

KKKK standards for turbines are the more accurate conversions and that the other values are in 

error.

Response 10.4-4: The EPA thanks the commenter for their response and the EPA is only

finalizing subpart TTTT of part 60 in this rulemaking and not finalizing changes to subparts Da 

and KKKK of part 60.

Comment 10.4-5: Commenter 0215 stated that they have identified several inconsistencies in 

the proposed regulatory language. The commenter felt that EPA should carefully review its 

proposed rule language to ensure consistency.

Response 10.4-5: The EPA thanks the commenter for their comment and the EPA has clarified 

subpart TTTT of part 60 in this rulemaking.
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10.4.1 Subpart TTTT or Subpart Da and KKKK

Comment 10.4-6: On the critical questions of which facilities and activities would be subject to 

the proposed rule, commenter 0247 said EPA had not provided commenters with clear, 

consistent proposed regulatory language and stated that it is not even certain what language EPA 

is proposing to adopt. Nor has EPA, in most cases, explained the reasons for departing from 

current regulatory language or for using inconsistent language in different subparts. These 

deficiencies require correction and an opportunity for the public to comment before a final rule 

can be adopted. 

To illustrate, the commenter noted that the "proposed" new regulatory text found in the docket 

for the proposed rule is shown as two alternatives: amendments to the existing EGU NSPS at 40 

CFR part 60, subparts Da and KKKK, or a wholly new subpart TTTT, which the commenter 

indicated do not contain the same applicability language. The commenter argued that EPA has 

not explained the reason for the differences. The commenter also noted that the Regulatory

Impact Statement included in the docket for the proposal (Docket ID EPA-HQ-OAR-2013-0603-

0025), which might otherwise help commenters understand what EPA was actually proposing to 

require, devotes only a handful of pages to NSPS for modified and reconstructed EGUs and says 

very little about applicability to the proposed standards. Because it addresses costs and benefits 

only by looking at a hypothetical plant, it gives no indication of which existing facilities EPA 

believes would be subject to the proposed rule.

Despite the extensive history behind the applicability criteria in existing subpart Da, the 

commenter stated that the proposal indicates EPA is considering numerous changes to the 

language but in many cases does not provide a reasoned explanation, or any explanation at all, 

for the change.

For example, in the "Proposed Regulatory Text" document, if subpart Da was amended, the 

commenter noted it would apply to modified or reconstructed EGUs "constructed for the purpose 

of supplying more than one-third of its potential electric output." The current subpart Da reads 

similarly. But if EPA instead were to promulgate a new subpart TTTT, EPA is proposing that it 

apply to a modified or reconstructed EGU "constructed for the purpose of supplying one-third or 

more of its potential electric output." The proposal does not explain why subpart TTTT replaces 

the "more than" criterion with "or more."

Likewise, in the "Proposed Regulatory Text" document, the commenter noted that the 

determination of whether a CHP unit is eligible to calculate its "net electric sales" by subtracting 

power purchased to operate the thermal host is applied over a three-year rolling average in 

proposed amendments to subpart Da. However, the corresponding proposed language if EPA 

promulgates a new subpart TTTT would not determine CHP eligibility on a three-year rolling 

average basis. (There is no indication what time period would apply in subpart TTTT, so 

presumably the criterion would have to be met each year- compare "Proposed Regulatory Text" 

document p. 22 of 49 with p. 40 of 49). These and many other unexplained differences in 

regulatory text among the existing NSPS and the several versions of proposed language EPA has 

offered with the proposal need to be rationalized, and if applicability language different from the 

current regulations is needed, EPA must explain why.
10-24

Response 10.4-6: EPA disagrees that commenters did not have adequate information to allow 

them to comment on the various options for regulatory text.

Comment 10.4-7: Commenter 0187 noted that EPA co-proposed two options for codifying the 

proposed standards of performance for affected modified and reconstructed units--codifying the 

standards in existing 40 CFR part 60, subparts Da and KKKK, or creating a new subpart TTTT, 

which would include all standards of performance for CO2 (79 FR 34965). The commenter 

supported creating a new subpart TTTT and including all of the CO2 standards within one 

subpart.

Response 10.4-7: The EPA agrees with the commenter and is only finalizing TTTT of part 60 in 

the final rulemaking.

Comment 10.4-8: Multiple commenters (0197, 0214, 0242, 0260) supported EPA's proposal to 

codify the provisions in their respective subparts (subpart Da for IGCC and boilers and subpart 

KKKK for turbines), rather than creating a new subpart TTTT. Commenter 0260 stated that this 

approach would ensure consistency with EPA's longstanding approach of compiling all 

performance standards for a single source category into a separate subpart of the CFR, rather 

than creating a new subpart that combines source categories and only addresses certain 

standards, which the commenter said would be confusing and inefficiently organized. 

Commenter 0197 stated that codifying the proposed regulations in their respective subparts 

would make referencing the appropriate NSPS easier for state and local air pollution control 

agencies and the owners and operators of the affected facilities. All of the applicable regulations 

would be in one subpart, thereby minimizing confusion. In addition, there would be no need to 

reproduce definitions that are already contained in the respective subparts (i.e., definition of 

fossil fuel). Also, if future data supports changing an emissions limitation for one type of fuel or 

technology, it can be addressed without opening the entire regulation to comment. Therefore, 

while codifying the proposed regulations in a new subpart may not cause undue burden to the 

owner/operator or the permitting agencies, the commenter recommended codifying the 

provisions in their respective subparts.

Commenter 0213 stated that, with several exceptions that they describe elsewhere in their 

comment, EPA must retain the applicability provisions for affected sources that exist in the 

current regulations for subparts KKKK and Da, as well as those for subparts Db and Dc, which 

regulate smaller steam EGUs and gasification plants that do not utilize combined cycle 

technology. However, the commenter did not indicate whether this meant codifying the 

provisions in those existing subparts or simply ensuring that the applicability provisions in a new 

subpart TTTT are the same as those in the existing subparts.

Commenter 0214 argued that EPA had not taken the necessary steps required by CAA section 

111(b) to set standards under subparts Da and KKKK, much less a new subpart TTTT. Without 

taking these steps for either approach, the commenter said EPA's actions would be illegal if 

finalized as proposed. Putting aside these issues, however, to the extent that EPA fails to rescind 

the proposal, the commenter supported codification of a final rule reflecting the proper 

application of section 111(b) into existing subparts Da and KKKK, instead of combining these 

separate source categories into a new subpart TTTT.
10-25

Commenter 0214 noted that the source category that constitutes subpart TTTT is not itself 

identified in the CAA section 111(b)(1)(A) list of categories of stationary sources. See 36 FR 

5,931 (Mar. 31, 1971); 43 FR 38,872, 38,874 (Aug. 31, 1978); 40 CFR 60.16 (Aug. 21, 1979). In 

order to add a source category, the CAA requires EPA to prepare a listing decision. This listing 

is a prerequisite to promulgating NSPS standards, and it is only after inclusion on the CAA 

section 111(b)(1)(A) list that EPA may promulgate federal standards of performance for new 

sources. See CAA section 111(b)(1)(B) ("Within one year after the inclusion of a category of 

stationary sources in a list under subparagraph (A), the Administrator shall publish proposed 

regulations, establishing Federal standards of performance for new sources within such 

category."). In EPA's January 2014 re-proposed NSPS and again in EPA's MRPS, EPA did not 

revise the list of categories of stationary sources to include the subpart TTTT source category.

Commenter 0214 further stated that EPA cannot list categories of sources and then establish 

NSPS unless it has determined that the pollutant(s) from the source category "causes, or 

contributes significantly to, air pollution which may reasonably be anticipated to endanger public 

health or welfare." See CAA section 111(b)(1)(A). The commenter argued that EPA has failed to 

make the required endangerment and significant contribution finding for CO2 regardless of 

where these standards will be codified. This failure is particularly important with regard to 

evaluating TTTT because CO2 is the only pollutant for which subpart TTTT would have a 

standard, and it is the only pollutant for which this category would be constructed from the CAA 

section 111(b)(1)(A) list. For these reasons, but only after all the prerequisites of section 111 are 

satisfied, the commenter stated that EPA should promulgate CO2 standards for modified and 

reconstructed sources under subparts Da and KKKK.

Commenter 0242 argued that reclassification using a new subpart TTTT that would include 

GHG standards for all covered sources would represent a significant departure from precedent in 

establishing NSPS-- which has in the past been based on what has been achieved in practice--in 

that several different types of equipment are combined under a single standard based on their 

common industry. The commenter argued that this is EPA clearly picking a "winning fuel," 

natural gas, over a "losing fuel," coal. This type of approach goes beyond EPA historical 

precedent and regulatory authority. Section 111(b)(5) forbids EPA from restricting owners and 

operators to a particular technology to meet a standard of performance.

Response 10.4-8: This final rule includes all the requirements in subpart TTTT. See the 

preamble of this rule for the PEA’s rationale.

Comment 10.4-9: Commenter 0215 stated that EPA proposes to exempt Subpart TTTT from 

sections 60.8 (addressing performance tests, notice of performance tests, performance test 

reports, and audit sample requirements), 60.11 (including compliance requirements and opacity

requirements), 60.14 (addressing modification), 60.15 (addressing reconstruction), 60.16 

(priority list), and 60.18 (addressing general control device requirements). Proposed 

Applicability Text, Subpart TTTT section 60.5570 & Tbl. 3. UARG does not understand why the 

tests for modification and reconstruction in sections 60.14 and 60.15 would not apply to this 

proposal and, if they would not, what tests EPA proposes would apply. If the exclusion of those 

sections was intentional, EPA must issue a proposal defining modification and reconstruction for 

this subcategory.
10-26

Commenter 0215 also stated that in the proposed Subpart Da, applicability is limited to affected 

facilities that were constructed for the purpose of supplying and, for new units that actually

supply "more than one-third" of their potential electric output and more than 219,000 MWh net 

electric output to a utility power distribution system. Proposed Applicability Text, Subpart Da 

section 60.46Da(a)(1); see also 79 Fed. Reg. at 34,972 (describing Subpart Da). That provision is 

consistent with the current Subpart Da definition of "electric utility steam-generating unit" in 

section 60.41Da, which EPA does not propose to change, and EPA?s description of its proposal 

for CO2 standards for new boilers in January 2014.56 79 Fed. Reg. at 1445. However, in Subpart 

TTTT, EPA proposes to extend applicability to affected Subpart Da facilities that were 

constructed to supply and, for new units, that actually supply "one-third or more" of their

potential electric output as net electric sales. Proposed Applicability Text, Subpart TTTT section 

60.5509(a)(1), (2) and (3). The extension is not explained and is not appropriate.

Response 10.4-9: The EPA agrees with the commenter that 60.14 and 60.15 should be made 

applicable to the final rule for modification and reconstruction and is making that clarification as 

the EPA will not be setting new definitions of what modification and reconstruction are in this 

rulemaking. Additionally the applicability of the regulation to affected EGUs has been updated 

and the use of the new subpart TTTT makes this clearer.

10.4.2 Definitions

Comment 10.4-10: EPA's existing regulations define "reconstruction" as the "replacement of 

components of an existing facility to such an extent that (1) the fixed capital cost of the new 

components exceeds 50% of the of the fixed capital cost that would be required to construct a 

comparable new facility, and (2) it is technologically and economically feasible to meet the 

applicable standards." While acknowledging that few existing EGUs will undertake projects that 

will qualify a unit as reconstructed, EPA requested comment on whether to adjust the upper 

capital cost threshold within the range of 75-100% of the cost of an entirely new and comparable 

facility, such that facilities that exceed the limit become subject to new plant standards. EPA also 

requested comment on whether to retain the second part of the definition. 

Response 10.4-10: EPA is not making any change to the regulatory definition of 

“reconstruction” in 40 CFR 60.15.

Comment 10.4-11: Multiple commenters (0131, 0165, 0183, 0195, 0197, 0242, 0247) objected 

to EPA's proposal to establish an upper threshold of 75-100% of the cost of an entirely new 

facility to classify a reconstructed source as a new source. 

Response 10.4-11: EPA is not making any change to the regulatory definition of 

“reconstruction” in 40 CFR 60.15, and is not finalizing any upper threshold of costs to be used to 

distinguish reconstructed sources from newly constructed sources.

Comment 10.4-12: Commenter 0244 stated that EPA must specify in its final rule that, for the 

purposes of defining a reconstructed source, a "comparable entirely new unit" refers to a new 

source with the same technology and specifications as the existing source that is being 

overhauled. Facility owners have an incentive to define "comparable entirely new unit" in a 

manner as expensive as possible in order to avoid reaching the 50 percent threshold for fixed 
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capital costs, at which point the source is defined as a reconstructed unit and must comply with 

the performance standards for such units. However, EPA has consistently interpreted 40 CFR 

60.15 such that a "comparable entirely new unit" is simply a new version of the existing facility

in question, and not a new plant with different and updated technology (such as a coal plant 

equipped with CCS technology). For instance, the agency makes this clear in a 1997 applicability

determination letter from Region 9 regarding a gasoline bulk terminal replacement: 

The commenter said the cost comparison should be for replacement as the facility existed prior 

to the replacement project (i.e., like for like replacement). For example, if a facility had 100 feet 

of three inch piping from the premium gas pump to the rack, and it was replaced with 150 feet of 

4 inch piping, the facility should state the cost of the 4 inch piping as part of the actual project, 

but the cost for the comparable equipment should be for 100 feet of new 3 inch pipe. See Letter 

from Ron Krzywosinski, EPA, Region 9, to David Howecamp, Re: Gasoline Bulk Terminal 

Reconstruction and Comparable Facility, ADI Control No. 0000081 (Apr. 4, 1997).

The commenter noted that a Region 1 applicability determination letter from 1999 reflects the 

same position: The term "comparable entirely new facility" would consist of a new boiler with 

identical components to the repaired boiler. Although a new boiler would be subject to the NSPS 

and may have air pollution control equipment or newer pollutant reduction design features such 

as low NOx burners, reconstruction calculations do not include air pollution control equipment 

and must compare like components. See Letter from Michael P. Kenyon, EPA, Region 1, to 

Christine A. Flass, Re: Reconstruction of Oil-Fired Boiler, ADI Control No. 0200048 (Sep. 3, 

1999).

According to the commenter, other EPA offices have reached similar conclusions. See, e.g., 

letter from Michael Alushin, EPA, CAMPD, to Ellen Radow Sadat, Re: Reconstruction of a 

Stationary Combustion Turbine, ADI Control No. 0800031 (Feb. 28, 2008), attached as Ex. 13; 

Letter from James T. Wilburn, EPA, Region 4, to Richard E. Grusnick, Re: Parallel Brown Stock 

Washer Systems, ADI Control No. 0200030 (June 16, 1988 The Agency has also made clear that 

"when determining the cost of the comparable entirely new facility, one must include all of the 

components identified in the definition of the affected facility [in the applicable regulations], but 

cannot include components outside of the defined affected facility." See Letter from Kenneth 

Gigliello, EPA, CAMPD, to Laurie Guthrie, Re: Gas Turbine Refurbishment and Commence 

Construction, ADI Control No. 0900067 (July 3, 2008). Under the language of the proposed new 

source and reconstructed source rules, a "steam generating unit" is defined as "any furnace, 

boiler, or other device used for combusting fuel for the purpose of producing steam (nuclear 

steam generators are not included) plus any integrated equipment that provides electricity or 

useful thermal output to either the boiler or auxiliary equipment." 79 FR 1516 (proposed 40 CFR 

60.5580). This definition only covers the boiler itself and any integrated generating equipment--it 

does not encompass pollution control technology such as CCS systems.

The commenter also noted that, at the time EPA first defined reconstructed sources, it made clear 

that "[c]osts associated with the purchase and installation of air pollution control equipment (e.g., 

baghouses, electrostatic precipitators, scrubbers, etc.) are not considered in estimating the fixed 

capital cost of a comparable entirely new facility unless that control equipment is required as part 

of the process (e.g., product recovery)." 40 FR 58,416. The law on this point could hardly be 
10-28

clearer. Nevertheless, to deter source operators from raising meritless arguments to the contrary, 

the commenter urged EPA to state explicitly in the final rule that the term "comparable entirely 

new facilities" does not include CCS systems at coal-fired EGUs, but refers only to new 

equipment of the kind that both appears at the existing plant and meets the definition of "steam 

generating unit" that appears in the regulations.

Response 10.4-12: This final rule does not change the reconstruction provisions included in the 

general provisions.

Comment 10.4-13: Multiple commenters (0192, 0193, 0258, 0260) objected to EPA's proposal 

to expand the definition of "affected facility" to include co-located non-emitting energy

generation equipment that is included in the facility operating permit but not integrated into the 

operation of the affected facility. 79 FR 34,979. Commenter 0193 noted that EPA's objective in 

proposing this change was to avoid potential circumvention of the emission standards by sources 

that may rely on co-located non-emitting energy generation equipment at the facility. EPA also 

stated that the provision would provide additional flexibility to the regulated community through 

additional compliance options. While this may be true, commenter 0193 remained concerned 

over the effect this provision may have on discouraging the deployment of non-emitting 

generation. The commenter suggested that further discussion and understanding is needed on the 

full range of implications that could follow from making such a significant change to the 

definition of source. 

In addition to expanding the definition of "affected facility," commenter 0260 noted that EPA 

also proposed to include within the definition of a "utility boiler," "IGCC unit," and "stationary

combustion turbine" that is subject to the proposed requirements, any integrated device that 

provides electricity or useful thermal output to the boiler, the stationary combustion turbine or to 

power auxiliary equipment. The commenter 0260 that the proposed expansion of the definition 

of facilities would be a significant departure from past EPA policy, as contained in Agency

guidance documents and NSPS applicability determinations, which has long taken a narrow 

approach when determining the boundaries of an affected facility. For example, EPA guidance 

makes clear that equipment outside of the boiler is not part of the affected facility for NSPS 

purposes under 40 CFR part 60, subpart Da. An EPA guidance memorandum on the topic 

clarifies that a modified pulverized coal-fired steam generator is defined as including the 

pulverizer system, the combustion air system, the steam generation system, the draft system, and 

the fuel combustion system. It does not include equipment like the turbine. Applicability

determinations also make clear that an affected facility under subpart Da includes only the steam 

generating unit. A diagram attached to an applicability determination for the Florida Electric 

Power Coordinating Group shows that equipment like the turbine, generator, and condenser are 

not part of the affected facility. Similarly, in an applicability determination issued to NRG 

Energy, EPA noted that "a turbine is not part of the existing facility (i.e., the electric utility steam 

generating unit)." EPA should not reverse its long-standing, consistent policy of narrowly 

interpreting the boundaries of affected facilities. Doing so would upset decades of EPA policy 

and confuse issues already addressed in past applicability determinations.

Commenter 0192 argued that the proposed NSPS rules are intended to regulate CO2 emissions 

from fossil fuel-fired EGUs, 79 FR 34,960, and there is no basis for including other energy

generating equipment that does not emit CO2 at all. Further, the fact that non-emitting energy
10-29

generation equipment is included in an operating permit provides no basis for including them 

within the scope of the section 111 program. As EPA recognizes, a site may be much broader 

than an affected EGU, see, e.g., 79 FR 1489, and, as a result, an operating permit may cover a 

number of units beyond an EGU that may undergo a modification or reconstruction. There is no 

reason to include non-emitting energy equipment simply because it happens to be co-located at 

the same site.

Commenter 0258 noted that the EPA appears to be proposing a definition of the "affected 

facility" for new and modified sources that differs from the "affected facility" as defined in the 

proposed NSPS, 79 FR 1430, 1511 (Jan. 8, 2014), and in the proposed performance standards for 

existing sources ("ESPS"), 79 FR 34830, 34954 (June 18, 2014). Commenter 0258 argued that 

the EPA must apply consistent definitions across these three rulemakings.

According to commenter 0258, the EPA noted in the Legal Memorandum for the ESPS that these 

three rulemakings are interrelated and all address the same "affected EGUs." EPA, Legal 

Memorandum for Proposed Carbon Pollution Emission Guidelines for Existing Electric Utility

Generating Units, at 11 ("EPA Legal Memorandum"). Indeed, section 111(d) of the CAA 

provides that a source can be regulated under an existing source standard only if "a standard of 

performance under this section would apply if such existing source were a new source ..." 42 

U.S.C. 7411(d). The EPA argued that its authority to issue an ESPS is predicated not only on the 

issuance of the NSPS, but also on issuance of the new and modified source rule. See EPA Legal 

Memorandum at 12-13. Therefore, EPA regulations must treat the "new source" and "existing 

source" referenced in the statute as within the same defined category of "sources."

Commenter 0258 also argued that the provisions governing the definition of the "affected 

facility" are critical to understanding the applicability of the rules to a source's operations. 

Without a consistent definition of an "affected facility," sources could be subject to potentially

conflicting requirements. For example, a source could fall within the definition of "affected 

facility" under the rule applicable to modified and reconstructed sources, yet fall outside the 

definition of an "affected facility" subject to the ESPS. The EPA should avoid confusion inherent 

in finalizing inconsistent applicability language and adhere to a single definition of the term 

"affected facility." The specificity with which the EPA has defined the "affected facility" in the 

redline revisions to subpart Da set forth in the June 2014 Memorandum, including the proposed 

definitions of "net electric sales" and "net-electric output" found in proposed revisions to 40 

CFR 60.46a(k) is helpful; however, the EPA must clarify that the "affected facility" and 

associated definitions will be consistent across the three rulemakings governing CO2 emissions 

from "affected" EGUs.

Commenters 0142 and 0242 objected to EPA's proposal to amend the definition for "steam 

generating unit" to replace the existing language "plus any integrated combustion turbines and 

fuel cells" with the new language "plus any integrated equipment that provides electricity or 

useful thermal output to either the affected facility or auxiliary equipment" to read as follows: 

"any furnace, boiler, or other device combusting fuel for the purpose of producing steam (nuclear 

steam generators are not included) plus any integrated equipment that provides electricity or 

useful thermal output to either the affected facility or auxiliary equipment." EPA stated they

made this definition change in order to avoid circumvention of the intent of the emission 
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standards (e.g., by having auxiliary equipment provide steam to the EGU to increase the output 

of the EGU and not including the CO2 emissions in determining the emission rate). While 

commenter 0142 understood the EPA's reasoning for the proposed definition change, the 

commenter argued that the EPA should not expand the source category to include other 

emissions units regulated in other existing source categories. The expansion of the source 

category does not account for the numerous configurations of plants, nor has EPA evaluated the 

effect of expanding the applicability on BSER. Instead of expanding the definition of steam 

generating unit, EPA should address what parameters are included and what parameters are not 

included in the demonstration of compliance with the standard. Commenter 0242 feared that 

EPA may be implying emergency generators could also become subject to the rules.

Response 10.4-13: This final rule does not include co-located non-emitting generating sources. 

Integrated equipment is included to assure the units do not circumvent the requirements of this 

final rule and to add additional compliance options for the regulated community.

Comment 10.4-14: Commenter 0260 agreed with EPA that projects involving the installation of 

add-on control equipment required to meet CAA requirements for criteria and hazardous air 

pollutants should be exempted from the definition of "modification" under the current NSPS 

regulations. 79 FR 34,970. For this reason, the proposed standards would not apply to units 

undertaking such projects. Instead, these units would remain subject to regulation under section 

111(d). The exemption for pollution controls in 40 CFR 60.14(a)(5) avoids penalizing 

companies' efforts to comply with other environmental regulations and should be maintained. 

Other commenters (0152, 0169, 0258) requested that EPA clarify the definition of 

"modification," for varying reasons. Commenter 0169 noted that, with certain exceptions, EPA 

defines a "modification" to mean "a physical or operational change that increases the source's 

maximum achievable hourly rate of emissions." 79 FR 34992; 42 U.S.C. 11l(a)(4); 40 CFR 60.2, 

60.14(a). One important exception is the so-called PCP exception. 79 FR 34970 (citing 40 CFR 

60.14(e)(5)). EPA recognizes that some facility improvements may involve equipment changes 

to improve efficiency that actually increase a source's maximum achievable hourly emission rate, 

even while decreasing the actual output based emissions rate. Under the PCP exception, 

modifications undertaken for the primary purpose of installing pollution control technology do 

not subject the source to EPA's modified source rule. Commenter 0169 requested that EPA 

provide examples of pollution control projects that have fallen under this exemption in the past 

and evaluate before finalizing a rule.

Commenter 0152 agreed with EPA that few projects are expected to meet the NSPS definition of 

"modification" and trigger this proposed standard. The majority of efficiency improvement 

projects do not typically increase the emission rate of a pollutant, and many other projects will fit 

within the exclusion for pollution control projects. For clarity and certainty, commenter 0152 

requested that EPA provide that all efficiency improvement projects are excluded from the NSPS 

definition of a modification, and that EPA consider ways to minimize the impact of PSD NSR as 

well.

Commenter 0258 stated that there is a discrepancy in 40 CFR part 60 regarding the definition of 

"modification." Under section 60.2, modification is defined as "any physical change in, or 

change in the method of operation of, an existing facility which increases the amount of any air 
10-31

pollutant (to which a standard applies) emitted into the atmosphere by that facility or which 

results in the emission of any air pollutant (to which a standard applies) into the atmosphere not 

previously emitted. Under that definition, any increase in emissions constitutes a modification. 

Under section 60.14(1), however, the definition of modification is "any physical or operational 

change to an existing facility which results in an increase in the emission rate to the atmosphere 

of any pollutant to which a standard applies shall be considered a modification within the 

meaning of section 111 of the Act." Under this definition, only an increase in the rate of 

emissions would be a modification. Commenter requested that EPA modify those two definitions 

so that they do not conflict with one another.

Response 10.4-14: The commenters are directed to 40 CFR 60.14 which provides provisions for 

what constitutes a modification and provides some specific exemptions.

Comment 10.4-15: Commenter 0176 proposed adding the following definitions to section 

60.4421 of the NSPS for new units and to the corresponding modified unit NSPS:

Market Dispatched Generation Resource (MDGR): An electric generation unit which participates 

within a Federal Energy Regulatory Commission (FERC) certified Independent System Operator 

(ISO) market or the Electric Reliability Council of Texas ISO market whereby the ISO makes 

unit commitment and dispatch decisions for the most efficient and reliable operation of all of the 

generation resources located and participating within the ISO.

Balancing Authority: The responsible entity that integrates resource plans ahead of time, 

maintains load-interchange-generation balance within a Balancing Authority Area, and supports 

Interconnection frequency in real time.

Response 10.4-15: The EPA disagrees with the commenters and does not believe that these 

definitions should be added to the final rule as they do not provide any additional clarity in the 

provisions of the rule.

Comment 10.4-16: Commenter 0213 opposed EPA's proposed change to the definition of 

"potential electric output" to include the phrase "or the design net electric output efficiency" as 

an alternative to the default one-third efficiency value." 79 FR 34,972, 34,979-80. The 

commenter proposed eliminating applicability determinations based on capacity factors or 

efficiency values, instead imposing tiered emission limits based on a unit's annual hours of 

operation. This approach would obviate EPA's suggestion to include "net electric output 

efficiency" as an applicability determinant. In any event, the commenter stated that the Agency

should not adopt this amendment, which would serve no purpose other than to exempt larger CTs 

from regulation that would otherwise have been covered under the rule. The commenter 

advocated the opposite approach: the rule's applicability provisions should be expanded to 

include all CTs that provide electricity to the grid.

Response 10.4-16: This final rule adopts a modified version of the broad applicability approach 

we solicited comment on. The definition of potential electric output has been finalized to include 

the design efficiency of the unit. The primary impact of this is to impact the percentage electric 

sales threshold for non-base load and base load combustion turbines and not the general 

applicability.
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Comment 10.4-17: Commenter 0213 opposed EPA's proposed change to the definition of "net 

electric output" to include the phrase "of the thermal host facility or facilities," such that the 

proposed definition would read "... the gross electric sales to the utility power distribution system 

minus purchased power of the thermal host facility or facilities on a calendar year basis." 79 FR 

34,972, 34,979-80 The purpose of this provision would be to allow third-party cogenerating units 

that provide useful heat output to adjacent plants under different ownership to reduce their gross 

electric sales figures by the amount of power purchased by the adjacent facility, and hence 

potentially avoid coverage under the rule. The commenter opposed this amendment for both the 

new source rule and modified/reconstructed rule. Id. at 34,979; see also 79 FR 1460. There is no 

legal or policy basis for allowing a cogenerating unit to reduce its annual electricity sales figure 

simply because it provides useful thermal output to adjacent unit under different ownership, and 

the commenter believes that a unit that provides or is designed to provide any amount of 

electricity for sale to the grid should be covered under the rule.

Response 10.4-17: The intent of this final rule is to cover EGUs whose primary purpose is to 

sell electricity to the grid, not industrial units. Therefore, we are finalizing the applicability

provision that net sales account for electricity used by thermal host facilities.

Comment 10.4-18: Commenter 0247 disagreed with EPA's proposed changes to the definition 

of "net-electric sales." EPA proposed to recognize the simultaneous purchase and sale issue, 

through the definition of "net-electric sales," but the proposal would add an additional proviso 

onto the definition of "net-electric output" in existing 40 CFR 60.41Da. Purchase of electricity

needed to run the facility would only be subtracted out for those CHP facilities where "at least 

20.0 percent of the total gross or net energy output consists of electric or direct mechanical 

output and at least 20.0 percent of the total gross or net energy output consists of useful thermal 

output."1 The commenter indicated that those criteria might be an appropriate way to identify

facilities where cogeneration is a minimal aspect of the operation, or the unit is involved in 

"sham" cogeneration, but the appropriateness of ignoring the accounting fiction of simultaneous 

purchase and sales, which EPA has recognized repeatedly in the past, does not depend on, and 

should have nothing to do with, the relative percentages of electrical and thermal output realized 

by the CHP unit. The commenter recommended that the definition of "net-electric sales" should 

simply be stated as applying on a net basis to all CHP units, and EPA concerns about sham 

cogeneration should be addressed in the definition of "combined heat and power" or elsewhere in 

the rule.

Response 10.4-18: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs.

Comment 10.4-19: Commenter 0215 stated that EPA proposes numerous definitions in Subpart 

TTTT, some of which are similar (but not identical) to definitions in the corresponding 

provisions in proposed revisions to Subparts Da and KKKK, and to definitions in other subparts 

affecting EGUs. Proposed Applicability Text, Subpart TTTT section 60.5580, Subpart Da 

section 60.46Da(k), Subpart KKKK section 60.4421. The commenter felt that EPA should 

review its proposed definitions for consistency both between the proposed subparts and in other 

NSPS affecting EGUs.
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Response 10.4-19: The EPA thanks the commenter for their comment and has clarified that only

subpart TTTT of part 60 will be finalized.

10.5 REQUEST FOR EXTENSION

Comment 10.5-1: Multiple commenters (0119, 0136, 0251) requested a 45-day extension of the 

comment deadline for the proposed rule for modified and reconstructed sources, identical to that 

granted for the existing source proposed rule. The commenters noted that the issues and 

comments on these two rules are interrelated, and thus it made sense for the proposed rules to 

have identical comment deadlines. Commenters noted that the two proposed rules were jointly

released to the public and signed by the Administrator on June 2, 2014, and were both published 

in the Federal Register on June 18, 2014. In both proposed rules, EPA announced October 16, 

2014 as the deadline for submitting comments. EPA extended the deadline for submitting 

comments on the existing source proposed rule until December 1, 2014, but did not extend the 

deadline for submitting comments on the modified and reconstructed source proposed rule. 

Commenters requested that EPA extend the deadline for submitting comments on the modified 

and reconstructed proposed rule to December 1, 2014.

Response 10.5-1: The EPA offered for the modified and reconstructed 111(b) for EGUs a 120 

day comment period through October 16, 2014 and held public hearings at 4 locations across the 

US the week of July 28, 2014. The EPA believes that was adequate time and outreach to 

generate comments on the proposal.

Comment 10.5-2: Multiple commenters (0089, 0092, 0114, 0115) requested a 90-day extension 

of the public comment period from October 16, 2014, to January 14, 2015 for both the existing 

source rule and modified/reconstructed source rule, both of which were published in the Federal 

Register on June 18, 2014. Commenters noted that EPA has uploaded to the docket a tremendous 

volume of information on its proposals, including the Federal Register preambles, Regulatory

Impact Statements, Technical Support Documents, and over 600 additional documents. 

Commenters 0089 and 0092 stated that additional time was needed to understand and analyze 

this information than EPA had provided, including identifying and correcting errors in EPA's 

approach to establishing specific state goals. The commenters stated that EPA, the regulated 

community, and the public would benefit from a more thorough analysis, which would take 

many months rather than weeks. The commenters also noted that there is additional supporting 

information that EPA has yet to make available, and thus has not been analyzed, including 

detailed parsed files related to the IPM modeling. Commenter 0014 also mentioned EPA's 

requests for comments not only on the proposal but also on alternative "approaches," "scenarios," 

and "options," which the commenter said places an extraordinary burden on state agencies. 

Commenters 0089, 0092, and 0115 stated that EPA has proposed to regulate existing and 

modified/reconstructed EGUs in an unprecedentedly broad manner that would impact nearly 

every aspect of how electricity is generated, dispatched, transmitted, and used, and would create 

new EPA oversight over state authorities involved in these complex issues. Stakeholders need 

additional time to fully assess the enormous range of issues associated with such a program. 

Commenter 0115 argued that EPA had an obligation to ensure that the various stakeholders have 

an opportunity to adequately review the proposed rule.
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Response 10.5-2: The EPA offered for the modified and reconstructed 111(b) for EGUs a 120 

day comment period through October 16, 2014 and held public hearings at 4 locations across the 

US the week of July 28, 2014. The EPA believes that was adequate time and outreach to 

generate comments on the proposal.

Comment 10.5-3: Commenter 0075 requested a 180-day extension of time to comments on the 

modified source proposal, stating that the current deadline of October 16, 2014 did not provide 

adequate time to review the proposed rule and supporting documentation and to develop 

meaningful comments and recommendations. The commenter noted that the modified source 

proposal was lengthy, consuming over 35 pages of the Federal Register. There are also dozens of 

supporting documents, a significant number of which contain technical information and data that 

must be reviewed and analyzed, not to mention the fact that many of the support documents were 

not issued until days after the modified source proposal was published in the Federal Register, 

allowing for even less time for review. Moreover, comments to EPA's even lengthier existing 

source proposal, which is supported by over 600 documents that must be reviewed and assessed, 

are also due on October 16, 2014. Preparing comprehensive and meaningful comments to both 

the modified source proposal and the existing source proposal by the current comment deadline 

is a virtual impossibility. Furthermore, the historical nature of the proposal (i.e., the fact that this 

is the first time that EPA has proposed to regulate CO2 emissions from modified and 

reconstructed power plants), in and of itself justifies an extension of time to comment on the 

modified source proposal.

Response 10.5-3: This commenter appears to the referencing the proposed Clean Power Plan 

Emission Guidelines for Existing Electric Generating Units. The docket for this rulemaking 

contains all relevant supporting information. Additionally, the EPA offered for the modified and 

reconstructed 111(b) for EGUs a 120 day comment period through October 16, 2014 and held 

public hearings at 4 locations across the US the week of July 28, 2014. The EPA believes that 

was adequate time and outreach to generate comments on the proposal.

Comment 10.5-4: Commenter 0263, 0254 requested that EPA provide opportunity for further 

public evaluation and comment on this proposal as well as the proposed section 111(d) 

guidelines and NSPS. The commenter stated that, due to the quantity of requests for comment 

and the level of detail on which EPA is seeking comment, this proposal more resembles an 

advanced notice of proposed rulemaking. In addition to the proposal's premature condition, there 

is heightened public interest on all three proposals. The commenter anticipated that EPA would 

receive extensive comments and data which could influence and change the promulgated final 

rule. Moreover, the interdependence described above for all three rule proposals does not allow 

them to be severable. Fundamental pieces of these rules are dependent on each other. A decision 

made for one rule likely will have consequences in another.

Response 10.5-4: The EPA offered for the modified and reconstructed 111(b) for EGUs a 120 

day comment period through October 16, 2014 and held public hearings at 4 locations across the 

US the week of July 28, 2014. The EPA believes that was adequate time and outreach to 

generate comments on the proposal.

Comment 10.5-5: Commenter 0116 argued that, in light of clear violations of section 307, EPA 

should withdraw the modified sources rule immediately. The commenter noted that the comment 
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deadline on the rule was October 16, 2014 and was thus fast approaching. If EPA wished to press 

forward with the modified sources rule, the commenter requested that EPA should withdraw that 

rule and re-propose it with all the supporting documents and data required by section 307. The 

commenter requested that EPA should then provide 120 days from the re-proposal date to 

provide sufficient time for states and the public to review and comment. Alternatively, the 

commenter said EPA should--at a minimum--publish the missing data immediately and then 

extend the comment period 120 days from the date of such publication.

Response 10.5-5: This commenter appears to the referencing the proposed Clean Power Plan 

Emission Guidelines for Existing Electric Generating Units. The docket for this rulemaking 

contains all relevant supporting information. Additionally, the EPA offered for the modified and 

reconstructed 111(b) for EGUs a 120 day comment period through October 16, 2014 and held 

public hearings at 4 locations across the US the week of July 28, 2014. The EPA believes that 

was adequate time and outreach to generate comments on the proposal.

Comment 10.5-6: Commenter 0192 urged EPA to reopen the comment period on this 

rulemaking so that it can be realigned with the comment deadline for EPA's concurrent 

rulemaking for existing fossil fuel-fired EGUs under Section 111(d). The commenter stated that 

under EPA's approach, its proposed rulemakings for modified and reconstructed sources is 

inextricably tied to its proposed rulemaking for existing sources. Both were proposed and 

published on the same date and, in many respects, rely on the same underlying data.

Response 10.5-6: The EPA offered for the modified and reconstructed 111(b) for EGUs a 120 

day comment period through October 16, 2014 and held public hearings at 4 locations across the 

US the week of July 28, 2014. The EPA believes that was adequate time and outreach to 

generate comments on the proposal.

10.6 INCORPORATION BY REFERENCE

Comment 10.6-1: Multiple commenters (0145, 0172, 0189, 0193, 0211, 0237, 0244, 0260, 

0270, 0282) incorporated by reference their public comments on the January 2014 proposed rule 

for new units. Commenters noted that the proposed rule for modified and reconstructed units 

included many elements of the January 2014 proposal for new units, and as such they have 

already submitted many of their technical comments on this proposed rule in the comments they

filed on the January 2014 proposal for new units. They indicated they would refer to relevant 

portions of their comments on the January 2014 proposal when making similar points on this 

proposed rule. Commenter 0172 also noted that both rules have the same cornerstones, including 

EPA's 2009 Endangerment Finding, and EPA's annual GHG emissions inventories, which 

inventories are prepared by EPA in accordance with IPCC's internationally accepted guidelines 

(2006). 

Several commenters mentioned specific comments on the January 2014 proposal that are also 

relevant to this proposal. Commenter 0145 incorporated by reference their comment on why 

simple cycle turbines should be exempt from the rule. Commenter 0282 pointed to their 

comment that EPA's proposed exemptions to the section 111(b) standard were capricious, 

irrational and unjustified. Commenter 0270 objected to EPA's failure to account for the effect of 

SSM events on the achievability of the proposed standards. Commenter 0193 emphasized the 
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many significant changes affecting the utility industry, including most notably the increasing 

demand for highly efficient simple cycle turbines to support the growth in renewable power 

generation. Commenter 0193 also noted the concern by many commenters over the long-term inuse feasibility of the proposed emission standards and the appropriateness of the proposed cutpoint between large and small stationary combustion turbines. Commenter 0193 supported EPA's 

decision to revisit these important issues in this rulemaking. Commenter 0244 requested that 

EPA, in keeping with the proposed new source standard, designate efficient generation 

technology with partial CCS as BSER for reconstructed steam EGUs and impose a performance 

standard at least as stringent as 1,200 lbs CO2/MWh on a net output basis. Commenter 0260 

specifically noted their comments on (1) EPA's proposed monitoring requirements; (2) EPA's 

proposed continuous compliance requirements, including the proposal that compliance with the 

mass emissions rate limits be determined on a 12-operating-month rolling average basis; and (3) 

EPA's proposed notification, recordkeeping and reporting requirements.

Response 10.6-1: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.6-2: Commenter 0222 preemptively incorporated by reference their impending 

comments on the June 2014 existing source guidelines, stating that this proposal is inextricably

linked with EPA's other proposal to regulate CO2 emissions from existing EGUs. While the 

commenter appreciated the additional time to comment on EPA's existing source rule proposal, 

bifurcating comment on the rulemaking did not make sense.

Response 10.6-2: The EPA thanks the commenter for their comment and EPA points the 

commenter to the Response-to-Comment (RTC) document for 111(b) newly constructed EGUs 

and to the preamble for more detailed discussion on this comment. Both documents are available 

in the rulemaking dockets.

Comment 10.6-3: Multiple commenters (0142, 0183, 0214) incorporated by reference their 

comments on both the January 2014 new source rule and June 2014 existing source guidelines, 

noting the interrelated nature of the two rules. Commenter 0214 argued that because EPA has 

illegally attempted to regulate modified and reconstructed units as both "new sources" and 

"existing sources" simultaneously, this proposal is inextricably linked with EPA's other two 

proposals regarding fossil fuel-fired EGUs under section 111. The commenter noted that EPA 

has, in fact, specifically requested certain comments that directly relate to the other two 

proposals. The commenter noted that they already commented on the significant legal and 

technical flaws associated with EPA's January 2014 proposed new source rule and planned to 

submit similarly critical comments on EPA's proposed guidelines when due (December 1, 2014), 

and thus would not repeat those comments here. The commenter noted, however, that some of 

the same comments are directly relevant in this rulemaking because the correction of the flaws in 

EPA's other section 111 proposal would also address many of their concerns with the Agency's 

modified/reconstructed proposal. In particular, the commenter stated that EPA has 

proposed section 111(d) existing source emission guidelines that would require a complete 

restructuring of the electric power system as a whole, instead of imposing requirements that only 

apply to the affected facilities subject to section 111(d). The commenter said the unprecedented 
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breadth of the section 111(d) proposed guidelines thus raises significant concerns regarding 

EPA's treatment of modified and reconstructed sources.

Response 10.6-3: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.6-4: The public comments submitted by Utility Air Regulatory Group (UARG) 

regarding the proposed rule for modified/reconstructed units were incorporated by reference by 

multiple commenters. Some commenters (0146, 0150, 0157, 0173) cited UARG alone, while 

others (0152, 0156, 0158, 0177, 0183, 0201, 0203, 0227, 0229, 0236, 0239, 0241, 0248, 0254, 

0275) cited UARG along with one or more of the following organizations: the Edison Electric 

Institute (EEI), National Rural Electric Cooperative Association (NRECA), Class of '85, Coal 

Utilization Research Council (CURC), Gulf Coast Lignite Coalition (GCLC), Arizona Utilities 

Group (AUG), National Association of Manufacturers (NAM), National Mining Association 

(NMA), American Public Power Association (APPA), Electric Power Research Institute (EPRI), 

Florida Electric Power Coordinating Group (FCG), Florida Municipal Electric Association 

(FMEA), and other industry organizations. 

Commenter 0183 agreed with those who urged EPA to withdraw all three proposals (new, 

modified/reconstructed, and existing source rules) and, to the extent EPA further pursues GHG 

regulations, to work at the outset with the affected utilities to develop rules that are within the 

authority of the CAA, technically feasible, and capable of implementation without threatening 

the reliability and cost effectiveness of energy in Texas and across the United States.

Response 10.6-4: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.6-5: The public comments submitted by the National Rural Electric Cooperative 

Association (NRECA) regarding the proposed rule for modified/reconstructed units were 

incorporated by reference by multiple commenters. Some commenters (0145, 0153, 0161, 0176, 

0243, 0278) cited NRECA alone, while others (0152, 0179, 0191, 0203, 0254, 0275) cited 

NRECA along with one or more of the following organizations: Utility Air Regulatory Group 

(UARG), Edison Electric Institute (EEI), Class of '85, Gulf Coast Lignite Coalition (GCLC), 

Arizona Utilities Group (AUG), Florida Electric Power Coordinating Group (FCG), and Florida 

Municipal Electric Association (FMEA).

Response 10.6-5: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.6-6: The public comments submitted by the Edison Electric Institute (EEI) 

regarding the proposed rule for modified/reconstructed units were incorporated by reference by 

multiple commenters. Some commenters (0162, 0250) cited EEI alone, while others (0152, 0156, 

0158, 0171, 0177, 0189, 0227, 0229, 0239, 0248) cited NRECA along with one or more of the 

following organizations: Utility Air Regulatory Group (UARG), National Rural Electric 
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Cooperative Association (NRECA), Class of '85, Coal Utilization Research Council (CURC), 

North Dakota Lignite Energy Council (LEC), Arizona Utilities Group (AUG), and other industry

organizations.

Response 10.6-6: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.6-7: A variety of commenters incorporated by reference the public comments 

submitted by other organizations on the proposed rule for modified/reconstructed units. 

Commenters 0155 and 0228/0273 supported the public comments submitted by the Tri-State 

Generation and Transmission Association, Inc. and incorporated by reference Tri-State's 

comments addressing legal, technical, economic, and practical concerns raised by EPA's

proposal. 

Commenter 0212 supported the Gas Turbine Association's (GTA's) recommendation to exempt 

combined heat and power units to promote the deployment of this highly efficient technology, 

while commenter 0193 supported the GTA's recommended value of 1,500 MMBtu/h (HHV) as 

the appropriate cut-point between large and small turbines for both the new and modified and 

reconstruction proposed rulemakings.

Commenters 0144 and 0209 supported and incorporated by reference the comments submitted by

the American Public Power Association (APPA). Commenter 0209 noted that the APPA had 

prepared a valuable analysis of the proposed rule and provided legal insight that was not 

duplicated by the commenter in their public comments on the proposed rule. 

Commenter 0274 incorporated by reference the comments submitted by the National Mining 

Association (NMA), while commenter 0196 incorporated by reference the comments submitted 

by a broad industry coalition (the "Coalition"). Commenter 0180 supported and joined in the 

detailed comments submitted by a coalition of industry associations ("the Associations"), as well 

as the SSM Coalition. Commenter 0280 joined in the comments submitted by Sierra Club, 

Environmental Defense Fund (EDF), Natural Resources Defense Council (NRDC), and 

Earthjustice ("Joint Environmental Comments").

Commenter 0247 joined with numerous other trade associations and business organizations filing 

joint comments on the modified/reconstructed sources proposal, and incorporated those 

comments by reference. Commenter 0232 incorporated by reference all prior written and oral 

testimony and submissions to the Agency in this matter, including all citations and attachments, 

as well as all of the documents cited in and attached to their comments, as part of the 

administrative record in this action, Docket ID No. EPA-HQ-OAR-2013-0603.

Commenter 0290 submitted a late comment in which they supported the National Rural Electric 

Cooperative Association (NRECA) and the Class of '85 Regulatory Response Group. 

Response 10.6-7: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.
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10.7 NET OR GROSS MW OUTPUT

Comment 10.7-1: In the proposal for modified/reconstructed sources, EPA proposed net outputbased emission limits for utility boilers and IGCC units, and requested comment on whether to 

use either gross or adjusted gross output-based standards in the final rule. EPA also proposed 

gross output-based emission limits for NGCC turbines, and requested comment on whether to 

use a net output-based approach in the final rule. Multiple commenters (0144, 0145, 0152, 0157, 

0171, 0178, 0183, 0193, 0197, 0203, 0214, 0226, 0245, 0260) supported gross output-based 

standards, rather than net output-based standards, for all unit types. 

Gross energy output includes the gross electric or mechanical output from the affected facility 

minus any electricity used to power the feedwater pumps plus 75 percent of the useful thermal 

output. Net energy output includes the net electric or mechanical output from the affected facility

plus 75 percent of the useful thermal output, where net electric output is the amount of gross 

generation minus the electricity used to operate the plant (i.e., auxiliary loads); such uses include 

fuel handling equipment, pumps, fans, pollution control equipment, other electricity needs, and 

transformer losses. See Memorandum from U.S. Environmental Protection Agency, Office of 

Air Quality Planning and Standards to EGU NSPS Docket (EPA-HQ-OAR-2013-0603), 

Amended Regulatory Text (Proposed Applicability). June 2014.

Multiple commenters (0171, 0178, 0260) argued that EPA had offered no justification for 

treating modified and reconstructed fossil fuel boilers and IGCC units differently than newly 

constructed units. The commenters noted that EPA had proposed standards for modified and 

reconstructed boilers and IGCC units as net output emission rates, while proposing standards for 

newly constructed units as gross output emission rates.

Commenter 0157 argued that EPA had not justified the dichotomy in standards in the 

modified/reconstructed rule--proposing a net output standard for coal-fired units and a gross 

output standard for natural gas-fired combustion turbines. The commenter stated that it appeared 

to be explicitly designed to favor natural gas at the expense of coal. The commenter argued that 

EPA should remain focused on technology rather than fuel choices.

In supporting the use of gross output standards, commenter 0193 stated that gross output 

standards are fairer and more reliable than net output standards to measure emissions and 

compliance. Moreover, the proposed use of periodic fuel sampling as an acceptable monitoring 

method provides appropriate compliance assurance. Determining the net output of an EGU is 

complicated and prone to errors.

Commenter 0214 stated that the use of gross output allows the plant operator to account for 

electrical, mechanical, and thermal energy use by the plant, giving operators the needed 

flexibility to design systems in the most efficient and economic manner. Gross MWh output is 

also straightforward, simple, consistent, and directly measured. Furthermore, market drivers will 

continue to ensure that power producers operate efficiently because utilities have a strong 

incentive to ensure the gap between gross and net output is as small as possible, maximizing the 

return on investment. Commenter 0226 stated that it is sensible to consider all of a unit's insidethe-fence options for efficiency improvement. 
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Commenter 183 stated that due to the various emission controls that could be installed on a unit, 

the commenter believes the best measure of heat rate uses gross heat rate; otherwise, units 

heavily controlled by emission systems are penalized by their degraded heat rate (when 

measured on a net basis) due to comparatively greater auxiliary loads.

Commenter 0197 stated that a gross output-based standard is more appropriate than the net 

output-based standard because well-controlled fossil fuel-fired EGUs consume more energy to 

operate air pollution control devices (i.e., scrubbers, selective catalytic reduction devices, and 

particulate controls) than uncontrolled units. The gross output-based standards are appropriate 

for both new and existing fossil fuel-fired EGUs. The commenter stated that the definition of 

gross output should allow for 100 percent of the useful thermal energy being produced and used 

to be included, as opposed to 75 percent of useful thermal energy being produced as proposed. 

The commenter recommended that, regardless of whether the final rule uses a gross output or net 

output-based standard, 100 percent of the useful thermal energy should be credited.

Multiple commenters (0157, 0171, 0178, 0214, 0260) noted that a gross output-based standard is 

also consistent with the monitoring and reporting requirements under 40 CFR part 75 and with 

other programs (e.g., Acid Rain program), which already rely on gross megawatt data. 

Commenter 0245 indicated that using a gross output-based standard would avoid sending 

conflicting reports to the same agency. The commenter indicated it would also avoid factoring in 

the added parasitic loads from emissions control retrofits, avoiding potential future NSPS 

modification issues.

Multiple commenters (0144, 0145, 0171, 0178, 0203, 0214, 0260) argued that net-based 

standards are not appropriate for modified and reconstructed EGUs. Some commenters (0171, 

0178, 0203, 0260) noted that pollution control technology often imposes significant parasitic 

load requirements on an EGU. If EPA were to adopt a standard that was calculated on a net 

basis, that level would need to be even higher to account for parasitic load. However, given the 

potential range of control options and corresponding parasitic load requirements, arriving at such 

a standard would be impractical and would not further the objective of the proposal.

Commenter 0203 argued that EPA should base its prescribed standards on an analysis that 

examines those standards in the context of source category achievability, with performance 

adequately demonstrated considering costs, energy and non-air health impacts, i.e., by

conducting an appropriate inquiry into the correct standard(s) of performance. Stated another 

way, EPA should base net output standards on net output analyses, and gross output standards on 

gross output analyses, avoiding a mixing of the two very different measures of emissions. Such 

an approach decreases the likelihood of an arbitrary rulemaking. Therefore, as the Agency

proceeds forward with this rulemaking, gross output-based standards should be used for both 

categories of EGUs (boilers and turbines).

Commenter 0203 noted that heat rate improvement projects--which EPA seeks to require in its 

NSPS proposals, may trigger NSR review, as the pollution control exclusion no longer applies to 

NSR review (the exclusion is still available for purposes of NSPS review). If so, remaining coalfired units could have emissions for purposes of NSR evaluated on a net utilization basis, which 

would not (unfairly so) include parasitic loads caused by increased pollution controls. The 
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commenter stated that EPA did not address this concern in the proposal and argued that EPA 

should not exacerbate it by using net output standards for utility boilers and IGCC units.

Commenter 0214 noted that net MWh output is facility-specific and difficult to accurately 

calculate. For example, many facilities have transformers that support multiple units at the 

facility, making unit-level reporting difficult. More importantly, station electric services may

come from other outside sources to supply lighting, well pumps, and other ancillary loads. 

Additionally, some station services are dedicated per unit, while other station services may be 

measured at a facility level. Examples of facility-wide equipment that often serve more than one 

unit include coal handling equipment such as unloaders and conveyors, electric fire pumps, 

cooling tower makeup pumps, and pollution control equipment (e.g., FGD and baghouses). 

Accurately measuring and reporting all of these sources would require complex calculations and 

would naturally lead to variations among affected sources as well as inconsistencies in both 

reporting CO2 emission rates and complying with the proposed CO2 standard. The commenter 

said a net output-based standard would also discourage the deployment of technologies that 

could successfully reduce CO2 emissions at a lower cost, such as CHP and co-generation.

Commenter 0145 noted that, as currently proposed, utility boilers and IGCC units must 

demonstrate compliance with the applicable CO2 emissions/MWh standard based on the gross 

CO2 emissions from the affected facility divided by the facility's net energy output. Under this 

methodology, electricity that is generated by the affected facility but used to operate plant 

equipment such as pumps, fans and pollution control equipment is not used in determining 

compliance with the standards, notwithstanding the fact that the CO2 emissions associated with 

the generation of this electricity is included in the compliance calculation. The commenter said 

this would result in a calculated emission rate that is artificially high. This would be particularly

problematic for affected facilities that have installed advanced pollution control systems that 

have large power demands. These facilities, which typically have installed controls under other 

CAA programs such as Regional Haze or the New Source Review Program, would have a more 

difficult time meeting the standards than similar uncontrolled facilities. To address this and have 

a compliance demonstration that accurately measures an affected facilities actual CO2 emission 

rate, the commenter said the final rule should base compliance for utility boilers and IGCC units 

on a gross emissions-gross energy output basis.

Commenter 0144 noted that, while EPA stated it was proposing net output CO2 emission rates, 

throughout the rule gross output was discussed. For example, EPA explained that the rule would 

require monitoring of "gross output," expressed in MWh. EPA also stated that part 75 monitoring 

systems used together with the "gross output" over a period of 12 months (a rolling average 

updated after each new operating month) would be used to calculate the average CO2 mass 

emissions rate. Further, initial compliance would be calculated by dividing the sum of the hourly 

CO2 mass emissions values by the total "gross output." In addition, recordkeeping requirements 

would require owners or operators to keep records of the calculations performed to determine the 

total CO2 mass emissions and gross output for each operating month. Commenter 0144 argued 

that this net output-based reporting compliance alternative should be rejected. As EPA had 

already noted in the section 111(b) rulemaking, the only data available on CO2 emissions from 

EGUs currently is in the form of gross output from CEMS, and thus requiring reporting on a net 

output basis would be inconsistent with the current requirements, would add unwarranted costs 
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and burden to utility reporting, and also "would have little impact...in terms of environmental 

performance." Thus, the commenter questioned why EPA was even requesting comment in this 

regard.

Response 10.7-1: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.7-2: Commenters 0169 and 0242 recommended that EPA develop a consistent 

standard (gross or net output-based) across all unit types, amongst all three proposed rules to 

minimize the collection of data in accordance with Paperwork Reduction Act (44 U.S.C. 3501 et 

seq.). Commenter 0169 noted that EPA proposed a gross-output approach in the NSPS 

rulemaking, proposed a net-output approach in the ESPS rulemaking, and proposed a net-output 

based approach for fossil fuel-fired boilers and IGCC units in the modified/reconstructed source 

rule but requested comment on using a gross-output approach. In addition, commenter 0242 

noted that EPA proposed gross output-based standards for modified/reconstructed natural gasfired stationary combustion turbines to be consistent with standards for newly constructed units 

as proposed in January 2014, but requested comment on whether the form of the standard should 

be set on a net-output basis. The EPA stated that both rules, the modified/reconstructed source 

rule and new source rule, would take the same approach once finalized. 

Commenter 0169 argued that EPA's intermixing of gross and net throughout this rule and the rest 

of the CPP makes it very difficult for sources to uniformly demonstrate heat rate amongst the 

rules. Furthermore, EPA's intermixing of gross and net throughout this proposed rule brings into 

question whether the BSER determinations reviewed are based on gross or net data and whether 

the emission rates reviewed are actually gross emission rates for the best plants since the rates 

proposed are only achievable if these were based on gross emission rates. In addition, the 

requirements in the modified source rule that require collection of both gross and net-based data 

are unnecessarily burdensome.

Commenter 0242 believes that if net output is the basis of the standard, then EPA should 

include a mechanism to account for and credit the parasitic load that is inherent to the operation 

of environmental control devices, which provide environmentally desirable benefits, if EPA 

chooses to continue to pursue the section 111(b) and 111(d) rulemakings.

Response 10.7-2: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.

Comment 10.7-3: Commenter 0241 supported net output-based standards. The commenter 

noted that the proposed CO2 emissions limits for the utility boiler and IGCC category are 

expressed in units of mass of CO2 per unit of net energy output, specifically in lb CO2/MWh-net. 

The proposed CO2 emissions limits for natural gas-fired stationary combustion turbines are 

expressed in units of mass of CO2 per unit of gross energy output, specifically in lb CO2/MWhgross. The EPA solicited comment on whether a net-output based approach should be used for 

the natural gas-fired units. Commenter 0241 suggested that the EPA be consistent in its approach 

and use net output for all units, since this is more characteristic of the unit's actual operation.
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Response 10.7-3: The EPA points the commenter to the Response-to-Comment (RTC) 

document for 111(b) newly constructed EGUs and to the preamble for more detailed discussion 

on this comment. Both documents are available in the rulemaking dockets.