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### 40 CFR 49.5512
This document is current through the April 11, 2016 issue of the Federal Register



### § 49.5512 Feder al Implementation Plan Provisions for Four Corners Power Plant, Navajo Nation.

(a) Applicability. The provisions of this section shall apply to each owner or operator of the coal
burnin g equipment designated as Units 1, 2, 3, 4, and 5 at the Four Corner s Power Plant (the Plant) on the Navajo Nation Indian Reservation located in the Four Corners Interstate Air Quality Control Region ( see 40 CFR 81.121 )

. Uni ts 1, 2, and 3 at the Four Corners Power Plant permanently ceased operation by January 1, 2014, pursuant to the requirements of paragraph (i) (3).
(b) Compliance Dates. Compliance with the requirements of this section is required upon the
effective date of this rule unless otherwise indicated by compliance dates contained in specific provisions.
(c) Definitions. For the purposes of this section paragraphs (a)

– (j) : (1) [reserved] Affirmative defense means, in the context of an enforcement proceeding, a response or defense put forward by a defendant, regarding which the defendant has the burden of proof, and the merits of which are independently and objectively evaluated in a judicial or administrative proceeding.
(2 ) Air pollution control equipment inclu des baghouses, particulate or gaseous scrubbers, and any other apparatus utilized to control emissions of regulated air contaminants which would be emitted to the atmosphere.
(3) Business Day. Business day means a normal working day, excluding weekends and Federal Holidays.
(4) Daily average means the arithmetic average of the hourly values measured in a 24

- hour period.
(5) Excess emissions means the emissions of air contaminants in excess of an applicable emissions limitation or requirement.
(6) Heat input means heat derived from combustion of fuel in a Unit and does not include the heat input from preheated combustion air, recirculated flue gases, or exhaust gases from other sources. Heat input shall be in accordance with 40 CFR Part 75.
(7) Malfunction me ans any sudden and unavoidable failure of air pollution control equipment or process equipment or of a process to operate in a normal or usual manner. Failures that are caused entirely or in part by poor maintenance, careless operation, or any other preven table upset condition or preventable equipment breakdown shall not be
considered malfunctions

. This rule provides an affirmative defense to actions for penalties brought for excess emissions that arise during certain malfunction episodes. An affirmativePage 2 of 13

de fense is not available if during the period of excess emissions, there was an exceedance of the relevant ambient air quality standard that could be attributed to the emitting source.
(8) Owner or Operator means any person who owns, leases, operates, controls, or supervises the Plant or any of the coal burning equipment designated as Units 1, 2, 3, 4, or 5 at the
Plant.
(9) Oxides of nitrogen (NO x ) means the sum of nitric oxide (NO) and nitrogen dioxide (NO 2 ) in the flue gas, expressed as nitrogen diox ide.
(10) Plant

- wide basis means total stack emissions of any particular pollutant from all coal burning equipment at the Plant.
(11) Regional Administrator means the Regional Administrator of the Environmental Protection Agency (EPA) Region 9 or his/her a uthorized representative.
(12) Shutdown means the cessation of operation of any air pollution control equipment, process equipment, or process for any purpose. Specifically, for Units 1, 2, or 3, shutdown begins when the unit drops below 40 MW net load wit h the intent to remove the unit from
service. For Units 4 or 5, shutdown begins when the unit drops below 300 MW net load with
the intent to remove the unit from service.
(13) Startup means the setting into operation of any air pollution control equipment, process equipment, or process for any purpose. Specifically, for Units 1, 2, or 3, startup ends when
the unit reaches 40 MW net load. For Units 4 or 5, startup ends when the unit reaches 400
MW net load.
(14) 24

- hour period means the period of time betwee n 12:01 a.m. and 12 midnight.
(d) Emissions Standards and Control Measures . The following emission limits shall apply at all
times.

–

(1) Sulfur Dioxide. No owner or operator shall discharge or cause the di scharge of sulfur dioxide (SO 2 ) into the atmospher e in excess of:

(i) 12.0 percent of the potential combustion concentration assuming all of the sulfur in the
coal is converted to SO 2 . This percent emitted is determined by a daily calculation of the plantwide heat input weighted annual average.

(ii) 17,900 pounds of total SO 2 emissions per hour averaged over any consecutive three (3) hour period, determined on a plant

- wide basis.
(2) Particulate Matter. No owner or operator shall discharge or cause the discharge of particulate matter from any coal burning equipment into the atmosphere in excess of 0.050 pounds per million British thermal unit (lb/MMBtu) of heat input (higher heating value) , as averaged from three sampling runs, each at 60 minutes in duration, each collecting a minimum sample of 30
d ry standard cubic feet

. (3) [reserved] Dust. Each owner or operator shall operate and maintain the existing dust suppression methods for controlling dust from the coal handling and storage facilities. Within ninety (90) days after promulgation of this sect ion, the owner or operator shall submit to thePage 3 of 13

Regional Administrator a description of the dust suppression methods for controlling dust from the coal handling and storage facilities, flyash handling and storage, and road sweeping
activities. Within 548 da ys of promulgation of this section e E ach owner or operator shall not emit dust with an opacity greater than 20 percent from any crusher, grinding mill, screening operation, belt conveyor, or truck loading or unloading operation.
(4) Opacity. No owner or op erator shall discharge or cause the discharge of emissions from the stacks of Units 4 and 5 into the atmosphere exhibiting greater than 20% opacity, excluding uncombined water droplets

, averaged over any six (6) minute period, except for one six (6)
minute period per hour of not more than 27% opacity. A ny unit for which the owner or operator installs, calibrates, maintains, and operates particulate matter CEMS under paragraph (e)(3)
shall b e exempt from the opacity standard in this paragraph (d)(4)

, and ass ociated requirements in paragraphs (e) and (f) to demonstrate compliance with the opacity standard

. (5) Oxides of nitrogen. No owner or operator shall discharge or cause the discharge of NO x into the atmosphere in excess of the amounts specified below

. (i ) From either Unit 1 or 2 in excess of 0.85 lb/MMBtu of heat input per unit, and
from either Units 3, 4

, or 5 in excess of 0.65 lb/MMBtu of heat input per unit averaged over any successive thirty (30) boiler operating day period from Units 4
and 5 ; (ii) In excess of 335,000 lb per 24

- hour period when coal burning equipment is operating, on a plant

- wide basis; for each hour when coal burning equipment is not operating, this limitation shall be reduced. If the unit which is not operating is Unit 1, 2, or 3, the limitation shall be reduced by 1,542 lb per hour for each unit which is not operating. If the unit which is not operating is Unit 4 or 5, the limitation shall be reduced by 4,667 lb per hour for each unit which is not operating.
(e) Testing and Monito ring. Upon completion of the installation of continuous emissions monitoring systems (CEMS) software as required in this section, c C ompliance with the
emissions limits set for SO 2 and NO x shall be determined by using data from a CEMS unless otherwise speci fied in paragraphs (e)(2) and (e)(4) of this section. Compliance with the emissions limit set for particulate matter shall be tested annually, or at such other time as requested by the Regional Administrator, based on data from testing conducted in accorda nce with 40 CFR part 60, appendix A, Methods 1 through 5, or any other method receiving prior written approval from the Regional Administrator. C ompliance with the emissions limits set for opacity shall be determined by using data from a Continuous Opacity Monitoring System (COMS) except during saturated stack conditions (uncombined water droplets)

. If the baghouse is operating within its normal operating parameters, the baghouse is not fully closed, and a high opacity reading occurs, it will be presumed th at the occurrence was caused by saturated stack conditions and shall not
be considered a violation.
(1) The owner or operator shall maintain and operate CEMS for SO 2 , NO or NO x , a diluent and, for Units 4 and 5 only, COMS, in accordance with 40 CFR 60.8 and 60.13

, and appendix B of 40 CFR part 60. Within six (6) months of promulgation of this section, the owner or operator shall install CEMS and COMS software which complies with the requirements ofPage 4 of 13

this section. The owner or operator of the Plant m ay petition the Regional Administrator for extension of the six (6) month period for good cause shown. Completion of 40 CFR part 75 monitor certification requirements shall be deemed to satisfy the requirements under 40 CFR
60.8 and 60.13 and appendix B of part 60. The owner or operator shall comply with the quality assurance procedures for CEMS found in 40 CFR part 75, and all reports required
thereunder sha ll be submitted to the Regional Administrator.
The owner or operator shall provide the Regional Administrator notice in accordance with
40 CFR 75.61

. (2) Sulfur Dioxide. For the purpose of determining compliance with this section, the sulfur dioxide inlet concentration (in lb/MMBtu) shall be calculated using the daily average percent
sulfur and Btu content of the coal combusted. The inlet sulfur concentrati on and Btu content shall be determined in accordance with American Society for Testing and Materials (ASTM) methods or any other method receiving prior approval from the Regional Administrator. A daily fuel sample shall be collected using the coal sampling tower conforming to the ASTM specifications. The analyses shall be done on the daily sample using ASTM methods or any other method receiving prior approval from the Regional
Administrator.
(i) The inlet sulfur dioxide concentration shall be calculated usi ng the following formula:

I s = 2(%S f )/GCV x 10 4 English units

Where:

I s = sulfur dioxide inlet concentrations in pounds per million Btu;

%S f = weight percent sulfur content of

the fuel; and

GCV = Gross calorific value for the fuel in Btu per pound.
(ii) The total pounds of SO 2 generated by burning the coal shall be calculated by multiplying the SO 2 inlet concentration by the daily total heat input determined by the 40 CFR Part 75 acid rain monitoring. This will determine the pounds of SO 2 produced per day . The SO 2 emitted from the stacks shall be determined by adding the daily SO 2 emissions from each stack as determined by the 40 CFR Part 75 acid rain monitors. Compliance with the emission limit shall be determined for each day by adding that day’s SO 2 emi ssions and that day’s SO 2 produced to the previous 364 days and then dividing the 365 days of emissions by the 365 days of SO 2 produced. Compliance is demonstrated if this fraction, converted to a percent, is equal to or less than 12.0 percent.
The data fr om the 40 CFR Part 75 monitors shall not be bias adjusted. If a valid SO 2 pounds per hour or heat input is not available for any hour for a unit, that heat input and
SO 2 pounds per hour shall not be used in the calculation of the annual plant

- wide

average.Page 5 of 13

(3) To assure continuous compliance with the particula te matter limits in paragraph (d)(2 ), the owner or operator shall either conduct quarterly particulate matter testing in accordance
with the testing specifications outlined in Table 5 of 40 CFR part 63 subpart UUUUU ; or install, calibrate, operate, and maintain a continuous parametric monitoring system (CPMS)
for that unit in accordance with 40 CFR part 63 subpart UUUUU ; or install , calibrate, maintain, and operate particulate matter CEMS in accordance with 40 CFR part 63 subpart
UUUUU. The owner or operator shall submit a written notification

, in accordance with paragraph (f), of intent to demonstrate compliance with this paragraph by using a PM CEMS.
This notification shall be sent at least 30 calendar days before the initial startup of the monitor for compliance determination purposes. The owner or operator may discontinue operation of the monitor and instead return to demonstration of compliance with this paragraph using quarterly PM testing by submitt ing written notification , in accordance with

pa ragraph (f), of such intent at least 30 calendar days before shutdown of the monitor for compliance determination purposes

. Nothing in this paragraph replaces or supersedes the requirements for PM CEMS in the Augus t 17, 2015 Consent Decree under paragraph (k). Particulate Matter. Particulate matter emissions shall be determined by averaging the results of three test runs. Each test run shall be sixty (60) minutes in duration and shall collect a
minimum volume of thi rty (30) dry standard cubic feet . Within six (6) months of promulgation of this section, particulate matter testing shall be conducted annually and at least six (6) months apart, with the equipment within 90 percent of maximum operation in
accordance with 40 CFR 60.8 and Appendix A to 40 CFR Part 60. The own er or operator shall submit written notice of the date of testing no later than 21 days prior to testing. Testing may be performed on a date other than that already provided in a notice as long as notice of the new date is provided either in writing or by telephone or other means acceptable to the Region 9 Enforcement Office, and the notice is provided as soon as practicable after the new testing date is known, but no later than 7 days (or a shorter period as approved by the Region 9 Enforcement Office) in advance of the new date of testing.
(4) Oxides of nitrogen. The total daily plant

- wide oxides of nitrogen emissions in pounds of
NO 2 per day shall be calculated using the following formula:

TTTT =

∑ ∑ iiii × HH iiii mm

= 1 nn ii = 1

Where:

TE = total plant

- wide ni trogen dioxide emissions (lb NO 2 /day);

E ij = hourly average emissions rate of each unit (lb NO 2 /MMBtu);

H ij = hourly total heat input for each unit (MMBtu);

n = the number of units of coal burning equipment operating during the hour;Page 6 of 13

m = the number of operating hours in a day, from midnight to midnight.
(5) Continuous emissions monitoring shall apply during all periods of operation of the coal burning equipment, including periods of startup, shutdown, and malfunction, except for CEMS breakdowns, repairs , calibration checks, and zero and span adjustments. Continuous monitoring systems for measuring SO 2 , NO x , and diluent gas shall complete a minimum of one cycle of operation (sampling, analyzing, and data recording) for each successive 15

- minute period. Ho urly averages shall be computed using at least one data point in each fifteen minute quadrant of an hour. Notwithstanding this requirement, an hourly average may be computed from at least two data points separated by a minimum of 15 minutes (where the unit operates for more than one quadrant in an hour) if data are unavailable as a result of performance of calibration, quality assurance, preventive maintenance activities, or backups of data from data acquisition and handling system, and recertification even ts. When valid SO 2 pounds per hour, NO 2 pounds per hour, or NO 2 pounds per million Btu emission data are not obtained because of continuous monitoring system breakdowns, repairs, calibration checks, or zero and span adjustments, emission data must be obtai ned by using other monitoring systems approved by the EPA to provide emission data for a minimum of 18 hours in at least 22 out of 30 successive boiler operating days. If a parameter essential for determining either the SO 2 pound per hour or the heat input is not valid or unavailable, that hour for that unit shall not be used in calculating the percent emissions of SO 2 for the plant

wide limit. The necessary software for determining compliance with the SO 2 plantwide annual average shall be installed and ope rating within 180 days of the effective date of this rule. The first day for determining compliance with the plantwide SO 2 limit shall be 365 days after the successful installation of the software.

(6) If the opacity standard in paragraph (d)(4) applies, the owner or operator shall demonstrate compliance with the opacity standard using one of the following options:

(i) o perate Continuous Opacity Monitoring Systems (COMS) and T he owner or operator shall maintain a set of opacity filters to be used as audit standards. Compliance with the opacity standard during period s of dry (unsaturated) stack conditions shall be determined using COMS. Compliance with the opacity standard during periods of wet (saturated) stack conditions shall be determined using visible emission performance testing specified in 40 CFR part 60 appendix A

- 4 , Method 9 , during the duration of the saturated stack condition , or

(ii) install, calibrate, operate, and maintain a continuous parametric monitoring system (CPMS) for that unit in acco rdance with 40 CFR part 63 subpart UUUUU, including the requirements for the development of site

- s p ecific monitoring plans and recordkeeping and reporting; and conduct periodic performance testing of visible emissions using the procedures specified in para graphs 40 CFR 60.49 Da (a)(3), or

(iii) monitor performance of the baghouses using a bag leak detection system in accordance with 40 CFR 60.48Da(o)(4), or an alternative bag leak detection system approved by the EPA, including requirements for the developme nt of site

- specific monitoring plans and recordkeeping and reporting; and conduct periodic performance testing of visible emissions using the procedures specified in paragraph 40 CFR 60.49 Da (a)(3).Page 7 of 13

(7) Nothing herein shall limit EPA’s ability to ask for a test at any time under Section 114 of the Clean Air Act, 42 U.S.C. 7414, and enforce against any violation.
(8) In order to provide reasonable assurance that the scrubbers for control of particulate matter from Units 1, 2, and 3 are being maintained and op erated in a manner consistent with good air pollution control practice for minimizing emissions, the owner or operator shall comply with the following provisions:
(i) The owner or operator shall develop a plan to monitor, record, and report parameter(s)
ind icative of the proper operation of the scrubbers to provide a reasonable assurance of compliance with the particulate matter limits in paragraph (d)(2) of this section. The owner or operator shall submit this plan to the Regional Administrator no later tha n sixty (60) days after the effective date of this FIP. The owner or operator shall implement this plan within 90 days of approval by the Regional Administrator and shall commence reporting the data generated pursuant to the monitoring plan in accordance w ith the schedule in paragraph (e)(8)(v) of this section. If requested by the Regional Administrator, this plan shall be revised and submitted to the Regional Administrator for approval within sixty (60) days of the request. The revised plan shall be implem ented within sixty (60) days of the Regional Administrator’s approval.
(ii) In the event that the owner or operator is unable to develop the plan required in paragraph (e)(8)(i) of this section due to technical difficulties, fails to submit the plan
within sixty (60) days of the effective date of this FIP, or the Regional Administrator disapproves the plan, the owner or operator shall install and operate devices to measure the pressure drop across each scrubber module and the total flow of scrubbing liquid t o the venturi section of each scrubber module. The data from these instruments shall be monitored and recorded electronically. A minimum of one reading every 15 minutes shall be used to calculate an hourly average which shall be recorded and stored for at
least a five

- year period. The owner or operator shall report in an electronic format either all hourly data, or one

- hour averages deviating by more than 30 percent from the levels measured during the last particulate matter stack test that demonstrated com pliance with the limit in this section. The owner or operator shall implement this requirement no later than one hundred eighty (180) days after the effective date of this FIP if it failed to submit the plan within sixty (60) days after the effective date of this FIP; or no later than 60 days after the Regional Administrator’s disapproval of the plan.
(iii) The monitoring required under paragraphs (e)(8)(i) and (e)(8)(ii) of this section shall apply to each Unit at all times that the Unit is operating, excep t for monitoring malfunctions, associated repairs, and required quality assurance or control activities (including, as applicable, calibration checks and required zero and span adjustments). A monitoring malfunction is any sudden, infrequent, not reasonabl y preventable failure of the monitoring to provide valid data. Monitoring failures that are caused in part by poor maintenance or careless operation are not malfunctions.Page 8 of 13

(iv) The owner or operator may petition the Regional Administrator for an extension of the sixty (60) day deadline. Such extension shall be granted only if the owner or operator demonstrates to the satisfaction of the Regional Administrator that:
(A) The delay is due to technical infeasibility beyond the control of the owner or operator; and
(B) The requested extension, if granted, will allow the owner or operator to successfully complete the plan.
(v) The owner or operator shall submit to the Regional Administrator reports of the monitoring data required by this section semi

- annually. The repo rts shall be postmarked within 30 days of the end of each calendar quarter.
(vi) The owner or operator shall develop and document a quality assurance program for the monitoring and recording instrumentation. This program shall be updated or improved as requested by the Regional Administrator.
(vii) In the event that a program for parameter monitoring on Units 1, 2, and 3 is approved pursuant to the Compliance Assurance Monitoring rule, 40 CFR Part 64, such program will supersede the provisions contained i n paragraph (e)(8) of this section.
(f) Reporting and Recordkeeping Requirements. Unless otherwise stated a A ll requests, reports, submittals, notifications, and other communications to the Regional Administrator or Administrator required by this section paragraph (f) and references therein shall be submitted

, unless instructed otherwise, to the Director, Navajo Environmental Protection Agency, P.O. Box 339, Window Rock, Arizona 86515, (928) 871

- 7692, (928) 871

- 7996 (facsimile) ; , and to the Director, Air D ivision, U.S. Environmental Protection Agency, Region IX, to the attention of
Mail Code: AIR

- 3 5 , at 75 Hawthorne Street, San Francisco, California 94105, (415) 972

- 39 74 90 , (415) 947

- 3579 (facsimile) ; , or by email at and to the Director, Enforcement Divisi on, U.S. Environmental Protection Agency, to the attention of Mail Code ENF

- 2

- 1 , at 75 Hawthorne Street, San Francisco, California, 94105 , (415) 972

- 3982, or by email to r9.aeo@epa.gov . For each unit subject to the emissions limitation in this section and upon completion of the installation of CEMS and COMS as required in this section, the owner or operator shall comply with the following requirements:
(1) For each emissions limit in this section, comply with the notification and recordkeeping requirements for CEMS and COMS compliance monitoring in 40 CFR 60.7(c) and (d) , and for visible emissions testing, if applicable under paragraph (e)(6), record and report results
of the tests in accordance with 40 CFR 60.7(d)

. For Units 4 and 5, periods of excess opacity due to water droplets shall be reported in the summary report required by 40 CFR 60.7(d)

. (2) For each day, provide the 365 day percent SO 2 emitted, the total SO 2 emitted that day,
and the total SO 2 produced that day. For any hours on any unit where data for SO 2 hourly pounds or heat input is missing, identify the unit number and monitoring device that did not produce valid data that caused the missing hour.Page 9 of 13

(3) Furnish the Regional Administrator wit h reports describing the results of the annual particulate matter emissions tests postmarked within sixty (60) days of completing the tests. Each report shall include the following information:
(i) The test date;
(ii) The test method;
(iii) Identification of the coal burning equipment tested;
(iv) Values for stack pressure, temperature, moisture, and distribution of velocity heads;
(v) Average heat input;

(vi) Emissions data, identified by sample number, and expressed in pounds per

MMBtu;
(vii) Arithmetic average of sample data expressed in pounds per MMBtu; and
(viii) A description of any variances from the test method

. (4) Excess Emissions Report. (i) For excess emissions (except in the case of saturated stack conditions) , the owner or operator shall notify the Navajo Environmental Protection Agency Director and the U.S. Environmental Protection Agency Regional Administrator by telephone or in writing within one business day (initial notification). A complete written repor t of the incident
shall be submitted to the Navajo Environmental Protection Agency Director and the U.S. Environmental Protection Agency Regional Administrator within ten (10) working days
of the initial notification. The complete written report shall incl ude: This notification
should be sent to the Director, Navajo Environmental Protection Agency, by mail to: P.O. Box 339, Window Rock, Arizona 86515, or by facsimile to: (928) 871

- 7996 (facsimile), and to the Regional Administrator, U.S. Environmental Prote ction Agency, by mail to the attention of Mail Code: AIR

- 5, at 75 Hawthorne Street, San Francisco, California 94105, by facsimile to: (415) 947

- 3579 (facsimile), or by e

- mail to: r9.aeo@epa.gov

. The complete written report shall include:
(A) The name and title of the person reporting;
(B) The identity and location of the Plant and Unit(s) involved, and the emissions point(s), including bypass, from which the excess emissions occurred or are occurring;
(C) The time and duration or expected duration of the excess emissions;
(D) The magnitude of the excess emissions expressed in the units of the applicable emissions limitation and the operating data and calculations used in determining the magnitude of the excess emissions;
(E) The nature of the condition cau sing the excess emissions and the reasons why excess emissions occurred or are occurring;Page 10 of 13

(F) If the excess emissions were the result of a malfunction, the steps taken to remedy the malfunction and the steps taken or planned to prevent the recurrence of su ch malfunction;
(G) For an opacity exceedance, the 6

- minute average opacity monitoring data or visible emission performance test results greater than 20 percent for the 24 hours prior to and during the exceedance for Units 4 and 5; and
(H) The efforts tak en or being taken to minimize the excess emissions and to repair or otherwise bring the Plant into compliance with the applicable emissions limit(s) or other requirements. For this reporting requirement, excess opacity due to saturated
stack conditions is exempted.
(ii) If the period of excess emissions extends beyond the submittal of the written report, the owner or operator shall also notify the Navajo Environmental Protection Agency
Director and EPA Regional Administrator in writing of the exact time and date when the excess emissions stopped. Compliance with the excess emissions notification provisions of this section shall not excuse or otherwise constitute a defense to any violations of this section or of any law or regulation which such excess emissio ns or malfunction may cause.
(g) Equipment Operations. At all times, including periods of startup, shutdown, and malfunction, the owner or operator shall, to the extent practicable, maintain and operate the Plant including associated air pollution control equipment in a manner consistent with good air pollution control practices for minimizing emissions. Determination of whether acceptable operating and maintenance procedures are being used will be based on information available to the Regional
Administrato r which may include, but is not limited to, monitoring results, opacity observations, review of operating and maintenance procedures, and inspection of the Plant. With regard to the operation of the baghouses on Units 4 and 5, placing the baghouses in serv ice before coal fires are initiated will constitute compliance with this paragraph. (If the baghouse inlet temperature cannot achieve 185 degrees Fahrenheit using only gas fires, the owner or operator will not be expected to place baghouses in service befo re coal fires are initiated; however, the owner or operator will remain subject to the requirements of this paragraph.)

(h) Enforcement.
(1) Notwithstanding any other provision in this implementation plan, any credible evidence
or information relevant to whether the Plant would have been in compliance with applicable requirements if the appropriate performance or compliance test had been performed, can be used to establish whether or not the owner or operator has violated or is in violation of any
standard in the plan.
(2) During periods of startup and shutdown the otherwise applicable emission limits or requirements for opacity and particulate matter shall not apply provided that:
(i) At all times the facility is operated in a manner consistent with good practice for minimizing emissions, and the owner or operator uses best efforts regarding planning, design, and operating procedures to meet the otherwise applicable emission limit;Page 11 of 13

(ii) The frequency and duration of operation in start

- up or shutdown mode a re minimized to the maximum extent practicable; and
(iii) The owner or operator’s actions during start

- up and shutdown periods are documented by properly signed, contemporaneous operating logs, or other relevant
evidence.
(3) Emissions in excess of the level of the applicable emission limit or requirement that occur due to a malfunction shall constitute a violation of the applicable emission limit. However, it shall be an affirmative defense in an enforcement action seeking penalties if the owner or operator has met with all of the following conditions:
(i) The malfunction was the result of a sudden and unavoidable failure of process or air pollution control equipment or of a process to operate in a normal or usual manner;
(ii) The malfunction did not result fro m operator error or neglect, or from improper operation or maintenance procedures;
(iii) The excess emissions were not part of a recurring pattern indicative of inadequate design, operation, or maintenance;
(iv) Steps were taken in an expeditious fashion to correct conditions leading to the malfunction, and the amount and duration of the excess emissions caused by the malfunction were minimized to the maximum extent practicable;
(v) All possible steps were taken to minimize the impact of the excess emissions o n ambient air quality;
(vi) All emissions monitoring systems were kept in operation if at all possible; and
(vii) The owner or operator’s actions in response to the excess emissions were documented by properly signed, contemporaneous operating logs, or other relevant
evidence.
(i) Regional Haze Best Available Retrofit Technology limits for this plant are in addition to the requirements of paragraphs (a) through (h) of this section. All definitions and testing and monitoring methods of this section apply to th e limits in this paragraph (i) except as indicated in paragraphs (i)(1) through (4) of this section. The interim NO x emission limit in paragraph (i)(2)(ii) of this section shall be effective 180 days after re

- start of the unit after installation of
add

- on post

- combustion NO x controls for that unit and until the plant

- wide limit goes into effect. The plant

- wide NO x limit shall be effective no later than 5 years after October 23, 2012. The owner or operator may elect to meet the plant

- wide limit early to remo ve the individual unit limits. Particulate limits for Units 4 and 5 shall be effective 60 days after restart following the scheduled major outage for Units 4 and 5 in 2013 and 2014.
(1) Particulate Matter from Units 4 and 5 shall be limited to 0.015 lb/MMB tu for each unit

. Particulate matter testing shall be performed in accordance with paragraph ( e )(3 ) of this
section. as measured by the average of three test runs with each run collecting a minimum of 60 dscf of sample gas and with a duration of at least 120 minutes. Sampling shall be performed according to 40 CFR Part 60 Appendices A

- 1 through A

- 3, Methods 1 through 4Page 12 of 13

and Method 5 or Method 5e. The averaging time for any other demonstration of the particulate matter compliance or exceedance shall be based on a 6

- hour average. Particulate testing shall be performed annually as required by paragraph ( e )( 3 ) of this section. This test with 120 minute test runs may be substituted and used to demonstrate compliance with the particulate limits in paragraph (d)(2) of this section.
(2) Plant

- wide nitrogen oxide emission limits.
(i) The plant

- wide nitrogen oxide limit, expressed as nitrogen d ioxide (NO 2 ), shall be 0.11 lb/MMBtu as averaged over a rolling 30

- calendar day period. NO x emissions for each calendar day shall be determined by summing the hourly emissions measured as pounds of NO 2 for all operating units. Heat input for each calendar day shall be determined by adding together all hourly heat inputs, in millions of Btu, for all operating units. Each day the rolling 30

- calendar day average shall be determined by adding together that day’s and the preceding 29 days’ pounds of NO 2 and dividing that total pounds of NO 2 by the sum of the heat input during the same 30

- day period. The results shall be the rolling 30

- calendar day

- average pound per million Btu emissions of NO x . (ii) The interim NO x limit for the first 750 MW boiler retro fitted with add

- on post

combustion NO x control shall be 0.11 lb/MMBtu, based on a rolling average of 30 successive boiler operating days.
(iii) Schedule for add

- on post

- combustion NO x controls installation
(A) Within 4 years of the effective date of this r ule, FCPP shall have installed add

on post

- combustion NO x controls on at least 750 MW (net) of generation to meet the interim emission limit in paragraph (i)(2)(ii) (A) of this section.
(B) Within 5 years of the effective date of this rule, FCPP shall have installed add

on post

- combustion NO x controls on all 2060 MW (net) of generation to meet the plant

- wide emission limit for NO x in paragraph (i)(2)(i) of this section.
(iv) Testing and monitoring shall use the 40 CFR part 75 monitors and meet the 40 CFR

par t 75 quality assurance requirements. In addition to these 40 CFR part 75 requirements, relative accuracy test audits shall be performed for both the NO x pounds per hour measurement and the heat input measurement. These shall have relative
accuracies of les s than 20 percent. This testing shall be evaluated each time the 40 CFR part 75 monitors undergo relative accuracy testing.
(v) If a valid NO x pounds per hour or heat input is not available for any hour for a unit, that heat input and NO x pounds per hour s hall not be used in the calculation of the 30 day plant

- wide rolling average.
(vi) Upon the effective date of the plant

- wide NO x average, the owner or operator shall have installed CEMS and COMS software that complies with the requirements of this
section.
(3 ) In lieu of meeting the NO x requirements of paragraph (i)(2) of this section, FCPP may choose to permanently shut down Units 1, 2, and 3 by January 1, 2014 and meet the requirements of this paragraph to control NO x emissions from Units 4 and 5. By Jul y 31,Page 13 of 13

2018, Units 4 and 5 shall be retrofitted with add

- on post

- combustion NO x controls to reduce
NO x emissions. Units 4 and 5 shall each meet a 0.098 lb/MMBtu emission limit for NO x expressed as NO 2 based on a rolling average of 30 successive boiler opera ting days. A ′′ boiler operating day ′′ is defined as any 24

- hour period between 12:00 midnight and the following midnight during which any fuel is combusted at any time at the steam generating unit.
Emissions from each unit shall be measured with the 40 CFR part 75 continuous NO x monitor system and expressed in the units of lb/MMBtu and recorded each hour. A valid
hour of NO x data shall be determined per 40 CFR part 75. For each boiler operating day, every valid hour of NO x lb/MMBtu measurement shall be avera ged to determine a daily average. Each daily average shall be averaged with the preceding 29 valid daily averages to determine the 30 boiler operating day rolling average. The NO x monitoring system shall meet the data requirements of 40 CFR 60.49Da(e)(2) (at least 90 percent valid hours for all operating hours over any 30 successive boiler operating days). Emission testing using 40 CFR part 60 Appendix A Method 7E may be used to supplement any missing data d ue to continuous monitor problems. The 40 CFR part 75 requirements for bias adjusting and data substitution do not apply for adjusting the data for this emission limit.
(4) By January 1, 2013, the owner or operator shall submit a letter to the Regional
Adm inistrator updating EPA of the status of lease negotiations and regulatory approvals required to comply with paragraph (i)(3) of this section. By December 31, 2013, the owner or operator shall notify the Regional Administrator by letter whether it will com ply with paragraph (i)(2) of this section or whether it will comply with paragraph (i)(3) of this section and shall submit a plan and time table for compliance with either paragraph (i)(2) or (3) of this section. The owner or operator shall amend and submi t this amended plan to the Regional Administrator as changes occur.
(5) The owner or operator shall follow the requirements of 40 CFR part 71 for submitting an application for permit revision to update its Part 71 operating permit after it achieves complia nce with paragraph (i)(2) or (3) of this section.
(j) Dust. Each owner or operator shall operate and maintain the existing dust suppression methods for controlling dust from the coal handling and ash handling and storage facilities. Within ninety (90) days after promulgation of this paragraph, the owner or operator shall develop a dust control plan and submit the plan to the Regional Administrator. The owner or operator shall comply with the plan once the plan is submitted to the Regional Administrator. The owner or operator shall amend the plan as requested or needed. The plan shall include a description of the dust suppression methods for controlling dust from the coal handling and storage facilities, ash handling, storage, and landfills, and road sweeping activities. Within 18 months of promulgation of this paragraph each owner or operator shall not emit dust with opacity greater than 20 percent from any crusher, grinding mill, screening operation, belt conveyor, or truck loading or unloading operation.

(k ) Emission limitati ons from August 17, 2015 Consent Decree. The emission limitations and other requirements fro m this paragraph (k)

, originally contained in a Consent Decree filed onPage 14 of 13

August 17, 2015 in the United States District Court for the District of New Mexico, are in addition to the requirements in paragraphs (a) through (j) of this section.

(1) Definitions . Every term expressly defined in this paragraph (k) shall have the meaning given that term herein. Every other term used in this paragraph (k) t hat is also a term used under the Act or in a federal regulation implementing the Act shall mean what such term means under the Act or those regulations.

(i) A “30

- Day Rolling Average NOx Emission Rate” for a Unit shall b e expressed in
lb/MM Btu and calcula ted in accordance with the following procedure: first, sum the total pounds of NOx emitted from the Unit during the current Unit Operating Day and the previous twenty nine (29) Unit Operating Days; second, sum the total h eat input to
the Unit in MM Btu duri ng the current Unit Operating Day and the previous twenty

- nine (29) Unit Operating Days; and third, divide the total number of pounds of NOx emitted during the thirty (30) Unit Operating Days by the total heat input during the thirty (30) Unit Operating Da ys. A new 30

- Day Rolling Average NOx Emission Rate shall be calculated for each new Unit Operating Day. Each 30

- Day Rolling Average NOx Emission Rate shall include all emissions that occur during all periods within any Unit Operating Day, including emissio ns from startup, shutdown, and Malfunction

.

(ii) A “30

- Day Rolling Average SO 2 Removal Efficiency” means the percent reduction
in the mass of SO 2 achieved by a Unit’s FGD system over a thirty (30) Unit Operating Day period and shall be calculated as follows: step one, sum the total pounds of SO 2 emitted as measured at the outlet of the FGD system for the Unit during the current Unit Operating Day a nd the previous twenty

- nine (29) Unit Operating Days as measured at the outlet of the FGD system for that Unit; step two, sum the total pounds of SO 2 delivered to the inlet of the FGD system for the Unit during the current Unit Operating Day and the previo us twenty

- nine (29) Unit Operating Days as measured at the inlet to the FGD system for that Unit (this shall be calculated by measuring the ratio of the
lb/ MMBtu SO 2 inlet to the lb/ MMBtu SO 2 outlet and multiplying the outlet pounds of
SO 2 by that ratio); step three, subtract the outlet SO 2 emissions calculated in step one
from the inlet SO 2 emissions calculated in step two; step four, divide the remainder calculated in step three by the inlet SO 2 emissions calculated in step two; and step five, multiply th e quotient calculated in step four by 100 to express as a percentage of removal efficiency. A new 30

- Day Rolling Average SO 2 Removal Efficiency shall be calculated for each new Unit Operating Day, and shall include all emissions that occur during all perio ds within each Unit Operating Day, including emissions from startup, shutdown,
and Malfunction

.

(iii) “Annual Tonnage Limitation” means the limitation on the number of tons of the pollutant in question that may be emitted from FCPP during the relevant cale ndar year (i.e., January 1 through December 31), and shall include all emissions of the pollutant emitted during periods of startup, shutdown and Malfunction.Page 15 of 13

(iv) “Baghouse” means a full stream (fabric filter) particulate emissions control device.

(v) “Clean Air Act” and “the Act” mean the federal Clean Air Act, 42 USC 7401

- 7671q, and its implementing regulations.

(vi) “CEMS” and “Continuous Emission Monitoring System,” mean, for obligations involving the monitoring of NOx and SO 2 emissions under this p aragraph (k) , the
devices defined in 40 CFR 72.2, and the SO 2 monitors required by this paragraph (k) for determining compliance with the 30

- Day Rolling Average SO 2 Removal Efficiency requirement set forth in this p aragraph (k)

.

(vii) “Continuous Operation ,” “Continuously Operate,” and “Continuously Operating” mean that when a pollution control technology or combustion control is required to be used at a Unit pursuant to this paragraph (k) (including, but not limited to, SCR, FGD, or Baghouse), it shall be operated at all times such Unit is in operation, consistent with the technological limitations, manufacturers’ specifications, good engineering and maintenance practices, and good air pollution control practices for minimizing
emiss ions (as defined in 40 C FR 60.11(d)) for such equipment and the Unit.

(viii) “Day” means calendar day unless otherwise specified in this paragraph (k)

.

(ix) “Emission Rate” means, for a given pollutant, the number of pounds of that pollutant emitted per million British thermal units of heat input (“lb/ MMBtu ”), measured in
accordance with this paragraph (k)

.

(x) “Flue Gas Desulfurization System” and “FGD” mean a pollution control device that employs flue gas desulfurization technology, including an absorber utilizing lime slurry,
for the reduction of SO 2 emissions.

(xi) “Fossil Fuel” means any hydrocarbon fuel, including coal, petroleum coke, petroleum oil, or natural gas.

(xii) “lb/ MMBtu ” means one pound of a pollutant per million British thermal units of heat input.

(xiii) “Make

- Right Vendor Guarantee” means, for an SCR, a guarantee offered by an SCR vendor that covers the SCR, including the catalyst, ammonia injection system, and support structure, under operating conditions (excluding any Malfunctions) above minimum operating t emperature for the SCR, the achievement of which is demonstrated solely during two performance tests: one performance test no later than 90 Days after initial operation of the SCR, and one performance test after no fewer than 16,000 hours of SCR operation, but no later than December 31, 2020 regardless of the number of operating hours achieved. If the SCR does not meet the guarantee in one of these twoPage 16 of 13

performance tests, a Make

- Right Vendor Guarantee requires the SCR vendor to repair, replace, or correct th e SCR to meet the specified guaranteed Emission Rate, which is demonstrated by successful achievement of a performance test.

(xiv) “Malfunction” means any sudden, infrequent, and not reasonably preventable failure of air pollution control equipment, proces s equipment, or a process to operate in a normal or usual manner. Failures that are caused in part by poor maintenance or careless operation are not Malfunctions.

(xv) “NOx Allowance” means an authorization or credit to emit a specified amount of NOx that is allocated or issued under an emissions trading or marketable permit program of any kind established under the Clean Air Act or an applicable implementation plan.
Alt hough no NOx Allowance program is applicable to FCPP as of the promulgation of this paragraph (k) , this definition of “NOx Allowance” includes authorizations or credits that may be allocated or issued under emissions trading or marketable permit programs

t hat may become applicable to FCPP in the future.

(xvi) “Operating Day” means any Day on which a Unit fires Fossil Fuel.

(xvii) “PM” means total filterable particulate matter, measured in accordance with the provisions of this paragraph (k)

.

(xviii) “PM CEM S” and “PM Continuous Emission Monitoring System” mean, for obligations involving the monitoring of PM emissions under this paragraph (k) , the equipment that samples, analyzes, measures, and provides, by readings taken at frequent intervals, an electronic and/or paper record of PM emissions.

(xix) “Removal Efficiency” means, for a given pollutant, the percentage of that pollutant removed by the applicable emission control device, measured in accordan ce with the provisions of this paragraph (k).

(xx) “Select ive Catalytic Reduction” and “SCR” mean a pollution control device that destroys NOx by injecting a reducing agent (e.g., ammonia) into the flue gas that, in the presence of a catalyst (e.g., vanadium, titanium, or zeolite), converts NOx into molecular
nit rogen and water.

(xxi) “Semi

- annual reports” are periodic reports that are submitted to EPA within 60 days after the end of each half of the calendar year.

(xxii) “ SO 2 Allowance” means an authorization to emit a specified amount of SO 2 that is allocated or issued under an emissions trading or marketable permit program of any kind established under the Clean Air Act or an applicable implementation plan, including as defined at 42 USC 7651a(3).Page 17 of 13

(xxiii) “Surrender” means to permanently sur render SO 2 Allowances so that such SO 2 Allowances can never be used to meet any compliance requirement under the Clean Air
Act or this paragraph (k)

.

(xxiv ) “Unit” means, solely for purposes of this paragraph (k) , collectively, the coal pulverizer, station ary equipment that feeds coal to the boiler, the boiler that produces steam for the steam turbine, the steam turbine, the generator, equipment necessary to operate the generator, steam turbine and boiler, and all ancillary equipment, including pollution co ntrol equipment, at or serving a coal

- fired steam electric generating unit at
FCPP.

(xxv) “Wet Stack” means a stack designed to be capable of use with a saturated gas stream constructed with liner material(s) consisting of one or more of the following: carbon steel with a protective lining (organic resin, fluoroelastomers, borosilicate glass blocks or a thin cladding of a corrosion

- resistant alloy), fiberglass

- reinforced plastic,
solid corrosion

- resistant alloy, or acid

- resistant brick and mortar.

(2) NO x Emission Limitations and Control Requirements

(i) The owner or operator shall install and commence Continuous Operation of an SCR
on or FCPP Unit 5 by no later than March 31, 2018. Commencing no later than 30 Operating Days thereafter, the owner or operator shall Continuously Operate the SCR
so as to achieve and maintain a 30

- Day Rolling Average NOx Emission Rate of no greater than 0.080 lb/ MMBtu , subject to the petition process paragraph (k)( 2 )(iii).

(ii) The owner or operator shall ins tall and commence Continuous Operation of an SCR
on the FCPP Unit 4 by no later than July 31, 2018. Commencing no later than 30 Operating Days thereafter, the owner or operator shall Continuously Operate the SCR
so as to achieve and maintain a 30

- Day Rolli ng Average NOx Emission Rate of no greater than 0.080 lb/ MMBtu , subject to the petition process in paragraph (k)( 2 )(iii)

.

(iii) At any time after March 31, 2019 but before December 31, 2020, the owner or operator may submit to EPA a petition for a proposed revision to the 30

- Day Rolling Average NOx Emission Rate of 0.080 lb/ MMBtu for either or both of the FCPP Units. The petition must demonstrate all of the following:

(A) That the design of the SCR system met the following parameters:

(1) The SCR system was designed to meet a NOx emission rate of 0.049
lb/ MMBtu , on an hourly average basis, under normal operating conditions once the minimum operating temperature of the SCR catalyst is achieved; andPage 18 of 13

(2) The owners or operators obtained a Make

- Right Vendor G uarantee for a NOx
emission rate of 0.049 lb/ MMBtu ;

(B) That best efforts have been taken to achieve the 30

- Day Rolling Average NOx
Emission Rate of 0.080 lb/ MMBtu . Best efforts includes but is not limited to exhausting the Make

- Right Vendor Guarantee and obtaining independent outside support from a registered professional engineer expert in SCR design. To demonstrate best efforts have been taken, the petition shall also include:

(1) the request for bid for the subject SCR;

(2) winning bid documents, incl uding all warranties and design information;

(3) NOx, NH 3 , and heat rate CEMS data and all related stack tests;

(4) daily coal quality data, including sulfur, ash, and heat content;

(5) operating and maintenance logs documenting all exceedances of the 0.080
lb/ MMBtu 30

- Day Rolling Average NOx Emission Rate and measures taken to correct them;

(6) vendor certification pursuant to a Make

- Right Vendor Guarantee that the
0.080 lb/ MMBtu 30

- Day Rolling Average NOx Emission Rate cannot be met by
the SCR as desi gned;

(7) a signed and sealed report by a registered professional engineer expert in SCR design confirming the 0.080 lb/ MMBtu 30

- Day Rolling Average NOx Emission Rate cannot be met by the SCR as designed; and

(8) affidavits documenting causes of failure to meet the 0.080 lb/ MMBtu 30Day Rolling Average NOx Emission Rate, signed and sealed by a licensed professional engineer;

(C) That the SCR system was properly operated and maintained pursuant to the manufacturer’s specifications for achieving and Continuous ly Operating to meet the design NOx emission rate of 0.049 lb/ MMBtu ; and

(D) That the owner or operator Continuously Operated the SCR and maximized the percent of flue gas or water bypassed around the economizer during any startup and
shutdown events in a manner to attain minimum operating temperature as quickly as reasonably possible during startup and to maintain minimum operating temperature during shutdowns as long as reasonably possible;Page 19 of 13

(E) That the owner or operator Continuously Operated the SCR and controlled the percent of flue gas or water bypassed around the economizer to maintain minimum operating temperature during load changes

.

(iv) In any petition submitted pursuant to paragraph (k)( 2 )(iii)

, the owner or oper ator shall include an alternate 30

- Day Rolling Average NOx Emission Rate, but in no event

may the owner or operator s propose a 30

- Day Rolling Average NOx Emission Rate
more than 0.085 lb/ MMBtu

. T he owner or operator shall also submit all studies, reports, and/or recommendations from the vendor and contractor(s) required by this p aragraph
and paragraph (k)( 2 )(iii) , evaluating each measure undertaken in an effort to meet a 30

- Day Rolling Average NOx Emission Rate of no greater than 0.080 lb/ MMBtu

. The

owner o r operator shall also deliver with each submission all pertinent documents and data that support or were considered in preparing such submission, as well as all data pertaining to the performance of the SCR in question since August 17, 2015 and the operati onal history of the Unit since August 17, 2015

.

(v) In addition to meeting the emissions rates set forth in paragraphs (k)( 2 )(i) and (k)( 2 )(ii), all Units at FCPP, collectively, shall not emit NOx in excess of the following Annual Tonnage Limitation: 31,060 tons of NOx per year in 2016 and 2017; 12,165 tons of NOx per year in 2018; and 4,968 tons of NOx per year in 2019 and thereafter

. H owever, if the 30

- Day Rolling Average NOx Emission Rate of 0.080 lb/ MMBtu required under Paragraphs (k)( 2 )(i) and (k) ( 2 )(ii) is revised pursuant to the petition process set forth in paragraphs (k)( 2 )(iii) and (k)( 2 )(iv), the annual NOx tonnage
limitations set forth as follows shall increase by the ratio of the new NOx rate in
lb/ MMBtu determined pursuant to paragraphs (k )( 2 )(iii) and (k)( 2 )(iv) divided by 0.080
lb/ MMBtu

.

(vi) In determining the 30

- Day Rolling Average NOx Emission Rate, t he owner or operator shall use CEMS in accordance with the procedures of 40 CFR p art 75, except that NOx
emissions data for the 30

- Day Ro lling Average NOx Emission Rate need not be bias adjusted and the missing data substitution procedures of 40 CFR p art 75 shall not apply. Diluent capping (i.e., 5 percent CO2) will be applied to the NOx emission calculation for any hours where the measured CO2 concentration is less than 5 percent following the procedures in 40 CFR p art 75, Appendix F, Section 3.3.4.1. The owner or operator s shall report semiannually all hours where diluent capping procedures were applied during the reporting period

.

(vii) For purposes of determining compliance with the Annual Tonnage Limitations in paragraph (k)(2)(v)

, the o wner s or operators shall use CEMS in accordance with the procedures specified in 40 CFR Part 75.

(viii) The owner or operator shall not sell, trade, or transfer any surplus NOx Allowances
allocated to FCPP that would otherwise be available for sale or trade as a result of the actions taken by the owner or operator s to comply with the requirements of this rule

.Page 20 of 13

(3) SO 2 Emission Limitations and Control Requirements

(i) Beginning on August 17, 2015

, the owner or operator shall c ontinuously o perate the existing FGDs at FCPP Unit 4 and Unit 5 so as to emit SO 2 from FCPP at an amount no greater than 10.0% of the potential c ombustion concentration assuming all of the sulfur in
the coal is converted to SO 2 . Compliance with this emissions standard shall be determined on a rolling 365

- Operating Day basis using the applicable methodologies set forth in paragraph (e)(2). The first day for determining compliance with this emissions standard shall be 365 Days after August 17, 2015 . The requirements of this paragraph shall remain in effect
until the owner or operator s achieve compliance with the requirements set forth in paragraphs (k )( 3 )(ii) and (k)( 3 )(iii)

.

(ii) By no later than March 31, 2018, the owner or operator s shall convert the existing ductwork and stack at FCPP Unit 5 to a Wet Stack, so as to eliminate the need to bypass flue gas around the FGD absorbers for reheat purposes. Commencing no later than 30 Operating Days thereafter, the owner or operator s shall c ontinuously o perate the existing
FGD at F CPP Unit 5 so as to achieve and maintain a 30

- Day Rolling Average SO 2 Removal Efficiency of at least 95.0%.

(iii) By no later tha n July 31, 2018, the owner or operator s shall convert the existing
ductwork and stack at FCPP Unit 4 to a Wet Stack, so as to eliminate the need to bypass flue gas around the FGD absorbers for reheat purposes. Commencing no later than 30 Operating Days thereafter, the owner or operator s shall Continuously Operate the existing
FGD at FCPP Unit 4 so as to a chieve and maintain a 30

- Day Rolling Average SO 2 Removal Efficiency of at least 95.0%.

(iv) In addition to meeting the emissions rates set forth in paragraphs (k)( 3 )(i), (k)( 3 )(ii) and (k)(3 )(iii), all Units at FCPP, collectively, shall not emit SO 2 in exc ess of the following Annual Tonnage Limitations: 13,300 tons of SO 2 per year in 2016 and 2017; 8,300 tons of
SO 2 per year in 2018; 6,800 tons of SO 2 per year in 2019 and thereafter.

(v) By each of the dates by which the owner or operator must comply with the 30

- Day Rolling Average SO 2 Removal Efficiency required under paragraphs (k)( 3 )(ii) and (k)( 3 )(iii)

, The owners or operator s shall install, certify, maintain, and operate FGD inlet
SO 2 and any associated diluent CEMS with respect to th at Unit in accordance with the requirements of paragraph (e)(1).

(vi) In determining the 30

- Day Rolling Average SO 2 Removal Efficiency, the owner or operator shall use CEMS in accordance with the procedures of 40 CFR p art 75, except that
SO 2 emissions data for the 30

- Day Rolling Average SO 2 Removal Efficiency need not be bias adjusted and the missing data substitution procedures of 40 CFR p art 75 shall not apply. Diluent capping (i.e., 5 percent CO2) will be applied to the SO 2 emission calculation for any
h ours where the measured CO2 concentration is less than 5 percent following the procedures
in 40 CFR p art 75, Appendix F, Section 3.3.4.1. The owners or operator s shall submit aPage 21 of 13

semi

- annual report that includes all hours where diluent capping procedures were applied during the reporting period

.

(vii) For purposes of determining compliance with the Annual Tonnage Limitations in Table 2, The owners or operators shall use CEMS in accordance with the procedures specified in
40 CFR p art 75.

(4) Use and Surrender of SO 2 Allowances

(i) The owner or operator shall not use SO 2 Allowances to comply with any requirement of paragraph (k) , including by claiming compliance with any emission limitation required paragraph (k) by using, tendering, or otherwise applying SO 2 Allowances to offset any
excess emissions.

(ii) Except as provided in paragraph (k)

, the owner or operator shall not sell, bank, trade, or transfer any SO 2 Allowances allocated to FCPP.

(iii) Beginning with ca lendar year 2015, and continuing each calendar year thereafter, the owner or operator shall s urrender to EPA, or transfer to a non

- profit third party selected by the owners or operator s for Surrender, all SO 2 Allowances allocated to FCPP for that
calendar year that the owner or operator do es not need in order to meet their own federal and/or state Clean Air Act statutory or regulatory requirements for the FCPP Units.

(iv) Nothing in paragraph (k)( 4 ) shall prevent the owners or operator s from purchasing or

o therwise obtaining SO 2 Allowances from another source for purposes of complying with Clean Air Act requirements to the extent otherwise allowed by law.

(v) For any given calendar year, provided that FCPP is in compliance for that calendar year
with all emissions limitations for SO 2 set forth in this section, nothing in paragraph (k), including the provisions of paragraphs (k)( 4 )(ii) and (k)( 4 )(iii) pertainin g to the Use and
Surrender of SO 2 Allowances, shall preclude the owner or operator from selling, trading, or transferring SO 2 Allowances allocated to FCPP that become available for sale or trade that calendar year solely as a result of:

(1) T he installatio n and operation of any pollution control technology or technique at Unit 4 or Unit 5 that is not otherwise required by p aragraph (k) ; or

(2) Achievement and maintenance of a 30

- Day Rolling Average SO 2 Removal Efficiency at Unit 4 or Unit 5 at a higher remo val efficiency than the 30

- Day Rolling Average SO 2 Removal Efficiency required by p aragraph (k)( 3 ) ; so long as the owner or operator submits a semi

- annual report of the generation of such surplus SO 2 Allowances
that occur after August 17, 2015

.Page 22 of 13

(vii) The o wner or operator shall s urrender, or transfer to a non

- profit third party selected by the owners or operator s for s urrender, all SO 2 Allowances required to be s urrendered pursuant to paragraph (k)( 4 )(iii) by April 30 of the immediately following calendar year. Surrender need not include the specific SO 2 Allowances that were allocated to FCPP, so long as the owners or operator s surrender SO 2 Allowances that are from the same year and that are equal to the nu mber required to be surrendered under paragraph (k)( 4 )(vii)

.

(viii) If any SO 2 Allowances are transferred directly to a non

- profit third party, the owner or operator shall include a description of such transfer in the next semi

- annual report submitted
to E PA. Such report shall:

(1) provide the identity of the non

- profit third

- party recipient(s) of the SO 2 Allowances and a listing of the serial numbers of the transferred SO 2 Allowances; and

(2) include a certification by the third

- party recipient(s) certify ing under the penalty of
law that the recipient(s) will not sell, trade, or otherwise exchange any of the allowances and will not use any of the SO 2 Allowances to meet any obligation imposed by any
environmental law. The certification must also include a s tatement that the recipient understands that there are significant penalties for submitting false, inaccurate or incomplete information to the United States.

(3) No later than the third semi

- annual report due after the transfer of any SO 2 Allowances, The owner or operator shall include a statement that the third

- party recipient(s) Surrendered the SO 2 Allowances for permanent surrender to EPA in accordance with the provisions of paragraph (k)( 4 )(ix) within one (1) year after the owners or operator s transferred the SO 2 Allowances to them. The owner or operator shall not have complied with the SO 2 Allowance Surrender requirements of subp aragraph (k)(4 )(viii) until all third

- party recipient(s) shall have actually Surrendered
the transferred SO 2 Allowa nces to EPA.

(ix) For all SO 2 Allowances surrendered to EPA, t he owner or operator or the third

- party recipient(s) (as the case may be) shall first submit an SO 2 Allowance transfer request form
to the EPA Office of Air and Radiation’s Clean Air Markets Div ision directing the transfer
of such SO 2 Allowances to the EPA Enforcement Surrender Account or to any other EPA account that EPA may direct in writing. Such SO 2 Allowance transfer requests may be made in an electronic manner using the EPA’s Clean Air Mark ets Division Business System or similar system provided by EPA. As part of submitting these transfer requests, the owners or operator s or the third

- party recipient(s) shall irrevocably authorize the transfer of these
SO 2 Allowances and identify

-- by name of account and any applicable serial or other
identification numbers or station names

-- the source and location of the SO 2 Allowances being surrendered.

(5) PM Emission Reduction RequirementsPage 23 of 13

(i) The owner or operator shall operate each FCPP Unit in a manner consistent with good air pollution control practice for minimizing PM emissions, as set forth in paragraph (g). In addition, with respect to FCPP Units 4 and 5, the owners or operator s shall, at a minimum,
to the e xtent practicable:

(1) operate each compartment of the Baghouse for each Unit (except the compartment provided as a spare compartment under the design of the baghouse), regardless of whether those actions are needed to comply with opacity limits;

(2) repair any failed Baghouse compartment at the next planned Unit outage (or unplanned outage of sufficient length);

(3) maintain and replace bags on each Baghouse as needed to achieve the required collection efficiency;

(4) inspect for and repair during the next planned Unit outage (or unplanned outage of sufficient length) any openings in Baghouse casings, ductwork, and expansion joints to minimize air leakage; and

(5) ensure that a bag leak detection program is developed and implemented to detect
leaks and promptly repair any identified leaks.

(ii) The owner or operator shall Continuously Operate a Baghouse at FCPP Unit 4 and Unit
5 so as to achieve and maintain a filterable PM Emission Rate no greater than 0.0150
lb/ MMBtu

.

(iii) Once in each calendar y ear, the owner or operator shall conduct stack tests for PM at FCPP Units 4 and 5. Alternatively, following the installation and operation of PM CEMS as required by paragraph (k)( 6 ) of this paragraph (k)

, The owners or operator s may seek
written approval t o forego stack testing and instead demonstrate continuous compliance with an applicable filterable PM Emission Rate using CEMS on a 24

- hour rolling average
basis.

(iv) Unless EPA approves a request to demonstrate continuous compliance using CEMS
under para graph (k)( 5 )(iii) to determine compliance with the PM Emission Rate established
in subp aragraph (k)( 5 )(ii)

, the owners or operator s shall use the reference methods and procedures (filterable portion only) specified in 40 CFR p art 60, App. A

- 3, Method 5,
Method 5 as described in s ubpart UUUUU, Table 5, or App. A

- 6, Method 17 (provided that Method 17 shall only be used for stack tests conducted prior to conversion of an FCPP Unit to a Wet Stack), or alternative stack tests or met hods that are requested by The owners or operator s and approved by EPA. Each test shall consist of three separate runs performed under representative operating conditions not including periods of startup, shutdown, or Malfunction. The sampling time for eac h run shall be at least 120 minutes and the volumePage 24 of 13

of each run shall be at least 1.70 dry standard cubic meters (60 dry standard cubic feet). The owners or operator s shall calculate the PM Emission Rate from the stack test results in
accordance with 40 CFR 60.8(f). The results of each PM stack test shall be submitted to EPA and NNEPA within 60 Days of completion of each test.

(v) Once each calendar year

, the owner or operator shall conduct a PM stack test for condensable PM at FCPP Units 4 and 5, using the reference methods and procedures set forth at 40 C.F.R. Part 51, Appendix M, Method 202 and as set forth in paragraph (iv) . This test shall be conducted under as similar operating conditions and as close in time as reasonably possible as the test for filte rable PM in paragraph (k)( 5 )(iv) . Each test shall consist of three separate runs performed under representative operating conditions not including periods of startup, shutdown, or Malfunction. The sampling time for each run shall
be at least 120 minutes an d the volume of each run shall be at least 1.70 dry standard cubic meters (60 dry standard cubic feet). The owner or operator shall calculate the number of pounds of condensable PM emitted in lb/ MMBtu of heat input from the stack test results in
accordance with 40 CFR 60.8(f). The results of the PM stack test conducted pursuant to this paragraph shall not be used for the purpose of determining compliance with the PM Emission Rates required by paragraph (k) . The results of each PM stack test shall be
submitt ed to EPA within sixty (60) Days of completion of each test. If EPA approves a request to demonstrate continuous compliance with an applicable PM Emission Rate at a Unit using PM CEMS under paragraph (k)( 5 )(iii) , annual stack testing for condensable PM
usi ng the reference methods and procedures set forth at 40 CFR p art 51, Appendix M, Method 202 is not required for that Unit.

(6) PM CEMS

(i) The owner or operator shall install, correlate, maintain, and operate a PM CEMS for FCPP Unit 4 and FCPP Unit 5 as specified below. The PM CEMS shall comprise a continuous particle mass monitor measuring particulate matter concentration, directly or
indi rectly, on an hourly average basis and a diluent monitor used to convert the concentration to units expressed in lb/ MMBtu . The PM CEMS installed at each Unit must be appropriate for the anticipated stack conditions and capable of measuring PM
concentratio ns on an hourly average basis. Each PM CEMS shall complete a minimum of one cycle of operations (sampling, analyzing and data recording) for each successive 15

- minute period. The owners or operators shall maintain, in an electronic database, the hourly

a verage emission values of all PM CEMS in lb/ MMBtu . Except for periods of monitor malfunction, maintenance

, or repair, the owner or operator shall continuously operate the PM CEMS at all times when the Unit it serves is operating.

(ii) By no later than Feb ruary 16, 2017, the owner or operator shall ensure that the PM CEMS are installed, correlated, maintained and operated at FCPP Units 4 and 5.

(iii) The owner or operator shall ensure that performance specification tests on the PM CEMS are conducted, and s hall ensure compliance with the PM CEMS installation plan andPage 25 of 13

QA/QC protocol submitted to and approved by EPA. The PM CEMS shall be operated in accordance with the approved plan and QA/QC protocol.

(iv) T he data recorded by the PM CEMS during Unit operati on, expressed in lb/ MMBtu on a 3

- hour, 24

- hour, and 30

- Day rolling average basis, shall be included in the semiannual report submitted to EPA in electronic format (Microsoft Excel

- compatible)

.

(v) Notwithstanding any other provision of paragraph (k) , excee dances of the PM Emission Rate that occur as a result of detuning emission controls as required to achieve the high level PM test runs during the correlation testing shall not be considered a violation of the requirements of this section ; provided, however , that the owners or operator s shall make best efforts to keep the high level PM test runs during such correlation testing below the applicable PM Emission Rate.

(vi) S tack testing conducted pursuant to paragraph (k)(5)(iv) shall be the compliance method
f

or the PM Emission Rates established by paragraph (k)(5) , unless EPA approves a request
under paragraph (k)(5)(iii) , in which case PM CEMS shall be used to demonstrate continuous compliance with an applicable PM Emission Rate on a 24

- hour rolling average
b asis. Data from PM CEMS shall be used, at a minimum, to monitor progress in reducing
PM emissions on a continuous basis.

(7) Reporting. The owner or operator shall submit all notifications , petitions, and reports under paragraph (k), unless otherwise specified, to EPA and Navajo Nation EPA in accordance with paragraph (f)

.