ARIZONA DEPARTMENT OF ENVIRONMENTAL QUALITY

TV Renewal Permit No. 53399 Page 1 of 109 May 31, 2012 APS-Cholla Generating Station AIR QUALITY CLASS I PERMIT

COMPA NY: Arizona Public Service Company
FACILITY: Cholla Generating Station
PERMIT #: 53399
DATE ISSUED: May 31, 2012 EXPIRY DATE: May 31, 2017

_____________________________________________________________________________________

SUMMARY

This Class I, Title V Air Quality Renewal Permit is issued to Arizona Public Service Company for the continued operation of the Cholla Generating Station. The facility is located approximately two miles east of the town of Joseph City on Interstate 40, in Navajo County, Arizona, a nd approximately 200 miles
northeast of Phoenix. This permit renews Permit #33500.

The Cholla Power Plant operates four pulverized coal -fired, steam boilers whic h generate approximately 1,160 megawatts of electricity. Each unit is a tang entially-fired, dry bottom furnace. Natural gas and diesel fuel are used as startup and stabilization fuels. Unit 4 is permitted to co-fire used oil/used oil fuel for energy recovery purposes. Unit 1, 3 and 4 are each equipped with fabric filter devices and Unit 2 is equipped with a mechanical dust collector for controlli ng particulate matter emissions. In addition, Unit 1 is equipped with a tray tower absorber system, Unit 2 is equipped with a four module flooded-disk scrubbers and four absorber towers, and Units 3 and 4 have spray tower absorber for controlling sulfur dioxide (SO 2 ) emissions. All four units are retrofitted with low-NO

x burners (LNBs) and over-fire air systems to reduce NO

x emissions.

The Cholla Generating Station is classified as a Class I, Major Source, pursuant to Arizona Administrative Code (A.A.C.) R18-2-101.64. The po tential emission rates of the following pollutants are greater than 100 tons per year: particulate matter, sulfur dioxide, nitrogen oxides, and carbon monoxide. The Cholla Power Plant is also subject to the Acid Rain Program of the Clean Air Act. This Class I permit is issued in accordance with Title V of the Clean Air Act, and Title 49, Chapter 3 of the Arizona Revised Statutes. All definitions, terms, and conditi ons used in this permit conform to those in the A.A.C. R18-2-101 et. seq. and 40 Code of Federal Regula tions (CFR), except as otherwise defined in this permit. Unless noted otherwise, references cited in the permit conditions refer to the A.A.C. All terms and conditions in this permit are enforceable by the Administrator of the United States Environmental Protection Agency (U.S. EPA), except for those terms a nd conditions that have been designated as "State requirements".TV Renewal Permit No. 53399 Page 2 of 109 May 31, 2012 APS-Cholla Generating Station TABLE OF CONTENTS

ATTACHMENT “A”: GENERAL PROVISIONS.................................................................................. 4

I. PERMIT EXPIRATI ON AND RENEWAL.................................................................................... 4

II. COMPLIANCE WITH PERMIT CONDITIONS ........................................................................... 4

III. PERMIT REVISION, REOPENING, REVOCATION AND REISSUANCE, OR

TERMINATION FOR CAUSE....................................................................................................... 4

IV. POSTING OF PERMIT.......................................................................................................... ......... 5

V. FEE PAYMENT ................................................................................................................. ............. 5

VI. ANNUAL EMISSION INVENTORY QUESTIONNAIRE ........................................................... 5

VII. COMPLIANCE CERTIFICATION ............................................................................................... 5

VIII. CERTIFICATION OF TRUTH, ACCURACY, AND COMPLETENESS .................................... 6

IX. INSPECTION AND ENTRY ....................................................................................................... ... 6

X. PERMIT REVISION PURSUANT TO FEDERAL HAZARDOUS AIR POLLUTANT

STANDARD...................................................................................................................... .............. 7

XI. ACCIDENTAL RELEASE PROGRAM......................................................................................... 7

XII. EXCESS EMISSIONS, PERMIT DEVIATIONS, AND EMERGENCY REPORTING ............... 7

XIII. RECORD KEEPING REQUIREMENTS ..................................................................................... 11

XIV. REPORTING REQUIREMENTS ................................................................................................. 11

XV. DUTY TO PROVIDE INFORMATION....................................................................................... 11

XVI. PERMIT AMENDMENT OR REVISION.................................................................................... 12

XVII. FACILITY CHANGE WITHOUT REVISION ............................................................................ 12

XVIII. TESTING REQUIREMENTS .................................................................................................... ... 13

XIX. PROPER TY RIGHTS........................................................................................................... ......... 14

XX. SEVERABIL ITY CLAUSE ........................................................................................................ .. 14

XXI. PERMIT SHIELD............................................................................................................. ............. 14

XXII. PROTECTION OF STRATOSPHERIC OZONE ......................................................................... 14

XXIII. NSPS AND NESHAP REQUIREMENTS.................................................................................... 14

ATTACHMENT “B” PERMIT SPECIFIC CONDITIONS................................................................. 15

I. GENERAL REQUIREMENTS .................................................................................................... 15

II. STEAM BOILER UNIT 1 ....................................................................................................... ..... 17

III. STEAM BOILER UNIT 2....................................................................................................... ...... 28

IV. STEAM BOILER UNIT 3........................................................................................................ ..... 50

V. STEAM BOILER UNIT 4......................................................................................................... .... 66

VI. COOLING TOWERS 3 AND 4 .................................................................................................... 8 4

VII. COAL PREPARATION PLANT .................................................................................................. 85

VIII. FLY ASH HANDLING FACILITY.............................................................................................. 87

IX. LIME HANDLING AND SLAKING ........................................................................................... 88TV Renewal Permit No. 53399 Page 3 of 109 May 31, 2012 APS-Cholla Generating Station X. FUGITIVE DUST REQUIREMENTS.......................................................................................... 90

XI. MOBILE SOURCE REQUIREMENTS........................................................................................ 91

XII. OTHER PERIODIC ACTIVITY REQUIREMENTS .................................................................. 92

XIII. INTERNAL COMBUSTION ENGINES ...................................................................................... 96

XIV. MERCURY REQUIREMENTS ................................................................................................... 97

ATTACHMENT “C”: EQUIPMENT LIST......................................................................................... 100

ATTACHMENT “D”: ACID RAIN PROVISIONS ............................................................................ 105

ATTACHMENT “E”: COMPLIANC E ASSURANCE MONITORING.......................................... 106TV Renewal Permit No. 53399 Page 4 of 109 May 31, 2012 APS-Cholla Generating Station 

### ATTACHMENT “A”: GENERAL PROVISIONS

AIR QUALITY CONTROL PERMIT NO. 53399

FOR
APS–CHOLLA GENERATING STATION

I. PERMIT EXPIRATION AND RENEWAL [ARS § 49-426.F, A.A.C. R 18-2-304.C.2, and -306.A.1]

A. This permit is valid for a period of five y ears from the date of issuance of Permit No.

53399.

B. The Permittee shall submit an application for re newal of this permit at least 6 months, but not more than 18 months, prior to the date of permit expiration.

II. COMPLIANCE WITH PERMIT CONDITIONS [A.A.C. R18-2-306.A.8.a and b]

A. The Permittee shall comply with all conditi ons of this perm it including all applicable requirements of the Arizona air quality statutes and air quality rules. Any permit noncompliance constitutes a violation of the Arizona Revised Statutes and is grounds for enforcement action; for permit termination, re vocation and reissuance, or revision; or for denial of a permit renewal application. In addition, noncompliance with any federally enforceable requirement constitutes a violation of the Clean Air Act.

B. It shall not be a defense for a Permittee in an enforcement action that it would have been

necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this permit.

III. PERMIT REVISION, REOPENING, REVOCATION AND REISSUANCE, OR

TERMI NATION FOR CAUSE [A.A.C. R18-2-306.A.8.c, -321.A.1, and -321.A.2]

A. The permit may be revised, reope ned, revoked and reissued, or terminated for cause. The filing of a request by the Permittee for a permit revision, revocation and reissuance, termination, or of a notification of planned changes or anticipated noncompliance does not stay any permit condition.

B. The permit shall be reopened and revised un der any of the following circumstances

1. Additional applicable requirements under th e Clean Air Act beco me applicable to the Class I source. Such a reopening shall only occur if there are three or more years remaining in the permit term. Th e reopening shall be completed no later than 18 months after promulgation of th e applicable requirement. No such reopening is required if the e ffective date of the requirement is later than the date on which the permit is due to expire, unl ess an application for renewal has been submitted pursuant to A.A.C. R18-2- 322.B. Any permit revision required pursuant to this subparagraph shall comply with the provisions in A.A.C. R18-2- 322 for permit renewal and shall reset the five-year permit term.

2. Additional requirements, including excess emissions requirements, become applicable to an affected source under the acid rain program. Upon approval by the Administrator, excess emissions offset plans shall be deemed to be incorporated into the Class I permit.

3. The Director or the Administrator determines that the permit contains a material
mistake or that inaccurate statements we re made in establishing the emissions standards or other terms or conditions of the permit.TV Renewal Permit No. 53399 Page 5 of 109 May 31, 2012 APS-Cholla Generating Station 4. The Director or the Administrator determ ines that the per mit needs to be revised or revoked to assure compliance with the applicable requirements.

C. Proceedings to reopen and reissue a permit, in cluding appeal of a ny final action relating to a permit reopening, shall follow the same pr ocedures as apply to initial permit issuance and shall, except for reopenings under Cond ition III.B.1 above, affect only those parts of the permit for which cause to reopen exists . Such reopenings shall be made as expeditiously as practicable. Permit reopenings for reasons ot her than those stated in
Condition III.B.1 above shall not result in a resetting of the five-year permit term.

IV. POSTING OF PERMIT [A.A.C. R18-2-315]

A. The Permittee shall post this permit or a certificate of permit issuance where the facility
is located in s uch a manner as to be clearly visible and accessible. All equipment covered by this permit shall be clearly marked with one of the following:

1. Current permit number; or

2. Serial number or other equipment ID number that is also listed in the permit to identify that piece of equipment.

B. A copy of the complete perm it shall be kept on site.

V. FEE PAYMENT [A.A.C. R18-2-306.A.9 and -326]

The Permittee shall pay fees to the Director pur suant to ARS § 49-426(E) and A.A.C. R18-2-326.

VI. ANNUAL EMISSION INVENTORY QUESTIONNAIRE [A.A.C. R18-2-327.A and B]

A. The Permittee shall complete and submit to th e Director an annua l emissions inventory questionnaire. The questionnaire is due by March 31st or ninety days after the Director makes the inventory form available each year , whichever occurs later, and shall include emission information for the previous calendar year.

B. The questionnaire shall be on a form provided by the Director and shall include the
inform ation required by A.A.C. R18-2-327.

VII. COMPLIANCE CERTIFICATION [A.A.C. R18-2-309.2.a, -309.2.c-d, and -309.5.d]

A. The Permittee shall submit a compliance certifi cation to the Director semiannually, which describes the compliance status of the source with respect to each permit condition. The
first certification shall be submitted no la ter than May 15th, and shall report the compliance status of the source during the pe riod between October 1st of the previous year and March 31st of the current year. The second certification shall be submitted no later than November 15th, and shall report the compliance status of the source during the period between April 1st and September 30th of the current year.

The compliance certifications shall include the following:

1. Identification of each term or condition of the permit that is the basis of the certification;

2. Identification of the methods or ot her means used by the Permittee for determining the compliance status with each term and condition during the certification period;TV Renewal Permit No. 53399 Page 6 of 109 May 31, 2012 APS-Cholla Generating Station 3. The status of compliance with the term s and conditions of this permit for the period covered by the certification, based on the methods or means designated in
Condition VII.A.2 above. The certificati ons shall identify each deviation and take it into account for consideration in the compliance certification;

4. For emission units subject to 40 CFR Part 64, the certification shall also identify as possible exceptions to compliance any period during which compliance is required and in which an excursion or exceedance defined under 40 CFR Part 64 occurred;

5. All instances of deviations from pe rmit requirements reported pursuant to
Condition XII.B of this att achment; and

6. Other facts the Director may require to determine the compliance status of the

source.

B. A copy of all compliance certifications shall also be subm itted to the EPA Administrator.

C. If any outstanding compliance schedule exists

, a progress report shall be submitted with the semi-annual compliance certificati ons required in Condition VII.A above.

VIII. CERTIFICATION OF TRUTH, ACCURACY AND COMPLETENESS

[A.A.C. R18-2-304.H ]

Any document required to be submitted by th is permit, including reports, shall contain a certification by a responsible official of truth, accuracy, and completeness. This certification shall state that, based on information and belief fo rmed after reasonable inquiry, the statements and information in the document are true, accurate, and complete.

IX. INSPECTION AND ENTRY [A.A.C. R18-2-309.4]

A. Upon presentation of proper credentials, the Permittee shall allow the Director or the authorized representative of the Director to:

B. Enter upon the Permittee’s premises where a s ource is located, emissions-related activity is conducted, or where records are required to be kept under the conditions of the permit;

C. Have access to and copy, at reasonable times, any records that are required to be kept under the conditions of the permit;

D. Inspect, at reasonable times, any facilities, equipment (including m onitoring and air pollution control equipment), practices, or op erations regulated or required under the permit;

E. Sample or monitor, at reasonable times, s ubstances or parameters for the purpose of assuring compliance with the per mit or other applicable requirements; and

F. Record any inspection by use of written, electronic, magnetic and photographic media.

X. PERMIT REVISION PURSUANT TO FEDERAL HAZARDOUS AIR POLLUTANT
STAND ARD [A.A.C. R18-2-304.C]

If this source becomes subject to a standard promulgated by the Administrator pursuant to Section 112(d) of the Act, then the Permittee shall, within twelve months of the date on which theTV Renewal Permit No. 53399 Page 7 of 109 May 31, 2012 APS-Cholla Generating Station standard is promulgated, submit an applica tion for a permit revision demonstrating how the source will comply with the standard.

XI. ACCIDENTAL RELEASE PROGRAM [40 CFR Part 68]

If this source becomes subject to the provisions of 40 CFR Part 68, then the Permittee shall comply with these provisions according to th e time line specified in 40 CFR Part 68.

XII. EXCESS EMISSIONS, PERMIT DEVIATIONS, AND EMERGENCY REPORTING

A. Excess Emissions Reporting [A.A.C. R18-2-310.01.A and -310.01.B]

1. Excess emissions shall be reported as follows:

a. The Permittee shall report to the Direct or any emissions in excess of the limits established by this permit. Su ch report shall be in two parts as specified below:

(1) Notification by telephone or facsimile within 24 hours of the
time when the Permittee first learned of the occurrence of excess emissions including all available information from Condition
XII.A.1.b below.

(2) Detailed written notification by submission of an excess

em issions report within 72 hours of the notification pursuant to Condition XII.A.1.a.(1) above.

b. The report shall contain the following information:

(1) Identity of each stack or other e mission point where the excess emissions occurred;

(2) Magnitude of the excess emissions expressed in the units of the applicable emission li mitati on and the operating data and calculations used in determining the magnitude of the excess emissions;

(3) Date, time and duration, or expected duration, of the excess emissions;

(4) Identity of the equipment from which the excess emissions

e manated;

(5) Nature and cause of such emissions;

(6) If the excess emissions were the result of a malfunction, steps taken to remedy the m alfunction a nd the steps taken or planned to prevent the recurrence of such malfunctions; and

(7) Steps taken to limit the excess emissions; if the excess emissions resulted from start-up or malfunction, the report shall contain a list of the steps taken to comply with the permit procedures.

2. In the case of continuous or recurring excess emissions, the notification requirem ents of this section shall be satisfied if the source provides the required
notification after excess emissions are first detected and includes in such
notification an estimate of the time th e excess emissions will continue. Excess emissions occurring after the estimated time period or changes in the nature of the emissions as originally reported shall require additional notification pursuant
to Condition XII.A.1 above. [A.A.C. R18-2-310.01.C]TV Renewal Permit No. 53399 Page 8 of 109 May 31, 2012 APS-Cholla Generating Station B. Permit Deviations Reporting [A.A.C. R18-2-306.A.5.b]

The Permittee shall promptly report deviations from permit requirements, including those attributable to upset conditions as defined in the permit, the probable cause of such deviations, and any corrective actions or pr eventive measures taken. Prompt reporting shall mean that the report was submitted to th e Director by certified mail, facsimile, or hand delivery within two working days of the time when emission limitations were exceeded due to an emergency or within two working days of the time when the owner or operator first learned of the occurrence of a deviation from a permit requirement.

C. Emergency Provision [A.A.C. R18-2-306.E]

1. An “emergency” means any situati on arising from sudde n and reasonable
unforeseeable events beyond the control of the source, including acts of God, that require immediate corrective action to restore normal operation, and that causes the source to exceed a technology-based emission limitation under the permit, due to unavoidable increases in emissions attributable to the emergency. An emergency shall not include noncompliance to the extent caused by improperly designed equipment, lack of preventativ e maintenance, careless or improper operation, or operator error.

2. An emergency constitutes an affirmativ e defense to an actio n brought for noncompliance with such technology-based emission limitations if Condition
XII.C.3 is met.

3. The affirmative defense of emergency shall be demonstrated through properly signed, contemporaneous operating logs , or other relevant evidence that:

a. An emergency occurred and that the Permittee can identify the cause(s) of the emergency;

b. The permitted facility was being properly operated at the time;

c. During the period of the emergency, the Per mittee took all reasonable steps
to minimize levels of emissions that exceeded the emissions standards or other requirements in the permit; and

d. The Permittee submitted notice of the emergency to the Director by
certified mail, facsimile, or hand deliv ery within two working days of the time when emission limitations were exceeded due to the emergency. This notice shall contain a description of the emergency, any steps taken to mitigate emissions, and corrective action taken.

4. In any enforcement proceeding, the Perm ittee s eeking to establish the occurrence of an emergency has the burden of proof.

5. This provision is in addition to any emergency or upset provision contained in

any applicable requirement.

D. Compliance Schedule [ARS § 49-426.I.5]

For any excess emission or permit deviation that cannot be corrected within 72 hours, the Permittee is required to submit a compliance schedule to the Director within 21 days of such occurrence. The compliance schedul e shall include a schedule of remedial measures, including an enforceable sequence of actions with milestones, leading to compliance with the permit terms or conditions that have been violated.

E. Affirmative Defenses for Excess Emissions Due to Malfunctions, Startup, and Shutdown
[A.A.C. R18-2-310]

1. ApplicabilityTV Renewal Permit No. 53399 Page 9 of 109 May 31, 2012 APS-Cholla Generating Station This rule establishes affirmative defen ses for certain emissions in excess of an
emission standard or limitation and a pplies to all emission standards or limitations except for standards or limitations:

a. Promulgated pursuant to Sections 111 or 112 of the Act;

b. Promulgated pursuant to Titles IV or VI of the Clean Air Act;

c. Contained in any Prevention of Significant Deterioration (PSD) or New Source Review (NSR) permit issued by the U.S. EP A;

d. Contained in A.A.C. R18-2-715.F; or

e. Included in a permit to meet the re quirements of A.A.C. R18-2-4 06.A.5.

2. Affirmative Defense for Malfunctions

E missions in excess of an applicable emission limitation due to malfunction shall
constitute a violation. When emissions in excess of an applicable emission limitation are due to a malfunction, the Pe rmittee has an affirmative defense to a civil or administrative enforcement proceedi ng based on that violation, other than a judicial action seeking injunctive relief, if the Permittee has complied with the reporting requirements of A.A.C. R18-2- 310.01 and has demonstrated all of the following:

a. The excess emissions resulted from a sudden and unavoidable breakdown of process eq uipment or air pollution control equipment beyond the reasonable control of the Permittee;

b. The air pollution control equipment, process equipment, or processes were at all times maintained and operated in a manner consistent with good practice for minimizing emissions;

c. If repairs were required, the repairs we re made in an expeditious fashion when the applicable emission limitations were being exceeded. Off-shift
labor and overtime were utilized wher e practicable to ensure that the repairs were made as expeditiously as possible. If off-shift labor and overtime were not utilized, the Permittee satisfactorily demonstrated that the measures were impracticable;

d. The amount and duration of the excess emissions (including any bypass operation) were minimized to the maximum extent practicable during periods of such emissions;

e. All reasonable steps were taken to minimize the impact of the excess

em issions on ambient air quality;

f. The excess emissions were not part of a recurring pattern indicative of inadequate design, operatio n, or maintenance;

g. During the period of excess emissions there were no exceedances of the
relevant am bient air quality standards established in Title 18, Chapter 2,
Article 2 of the Arizona Administrative Code that could be attributed to the emitting source;

h. The excess emissions did not stem from any activity or event that could
have been fo reseen and avoided, or planned, and could not have been avoided by better operations and maintenance practices;

i. All emissions monitoring systems we re kept in operation if at all practicable; and

j. The Permittee's actions in response to the excess emissions were
docum ented by contemporaneous records.TV Renewal Permit No. 53399 Page 10 of 109 May 31, 2012 APS-Cholla Generating Station 3. Affirmative Defense for Startup and Shutdown

a. Except as provided in Condition XII. E.3.b below, a nd unless otherwise provided for in the applicable requi rement, emissions in excess of an applicable emission limitation due to startup and shutdown shall
constitute a violation. When emi ssions in excess of an applicable emission limitation are due to startup and shutdown, the Permittee has an
affirmative defense to a civil or administrative enforcement proceeding based on that violation, other than a judicial action seeking injunctive relief, if the Permittee has complied with the reporting requirements of A.A.C. R18-2-310.01 and has demonstrated all of the following:

(1) The excess emissions could not have been prevented through careful and prudent plan ning and design;

(2) If the excess emissions were the result of a bypass of control equipm ent, the bypass was unavoida ble to prevent loss of life, personal injury, or severe damage to air pollution control equipment, production equipment, or other property;

(3) The air pollution control equipment, process equipment, or

processe s were at all times maintained and operated in a manner consistent with good practice for minimizing emissions;

(4) The amount and duration of the excess em issions (including any bypass operation) were minimized to the maximum extent practicable during periods of such emissions;

(5) All reasonable steps were taken to minimize the impact of the

excess emissions on ambient air quality;

(6) During the period of excess emissions there were no
exceedances of the relevant am bient air quality standards established in Title 18, Chapter 2, Article 2 of the Arizona Administrative Code that could be attributed to the emitting

source;
(7) All emissions monitoring systems we re kept in operation if at all practicable; and

(8) Contemporaneous records documented the Permittee’s actions in response to the exces s emissions.

b. If excess emissions occur due to a ma lfunction duri ng routine startup and shutdown, then those instances shall be treated as other malfunctions subject to Condition XII.E.2 above.

4. Affirmative Defense for Malfuncti ons during Scheduled Maintenance

If excess emissions occur due to a malf unction during scheduled maintenance, then those instances will be treated as other malfunctions subject to Condition
XII.E.2 above.

5. Demonstration of Reasonable and Practicable Measures

For an affirmative defen se under Cond ition XII.E.2 or XII.E.3 above, the Permittee shall demonstrate, through subm ission of the data and information required by Condition XII.E and A.A.C. R18-2-310.01, that all reasonable and practicable measures within the Permittee’ s control were implemented to prevent
the occurrence of the excess emissions.TV Renewal Permit No. 53399 Page 11 of 109 May 31, 2012 APS-Cholla Generating Station XIII. RECORD KEEPING REQUIREMENTS [A.A.C. R18-2-306.A.4]

A. The Permittee shall keep records of all requi red m onitoring information including, but not limited to, the following:

1. The date, place as defined in the permit, and time of sampling or measurements;

2. The date(s) analyses were performed;

3. The name of the company or entit y that performed the analyses;

4. A description of the analytical techniques or methods used;

5. The results of such analyses; and

6. The operating conditions as existing at the time of sampling or measurement.

B. The Permittee shall retain records of all requi red m onitoring data and support information for a period of at least 5 years from the date of the monitoring sample, measurement, report, or application. Support informa tion includes all calibration and maintenance records and all original strip-chart recordings or other data recordings for continuous monitoring instrumentation, and copies of all reports required by the permit.

C. All required records shall be maintained either in an unchangeable electronic format or in a handwritten logbook utilizing indelible ink.

XIV. REPORTING REQUIREMENTS [A.A.C. R18-2-306.A.5.a]

The Permittee shall submit the following reports:

A. Compliance certifications in accordance with Section VII of Attachment “A”.

B. Excess emission; permit deviation, and emergency reports in accordance with Section XII
of Attach ment “A”.

C. Other reports required by any condition of Attachment “B”.

XV

. DUTY TO PROVIDE INFORMATION [A.A.C. R18-2-304.G and -306.A.8.e]

A. The Permittee shall furnish to the Director, w ithin a reasonable ti me, any information that the Director may request in writing to determine whether cause exists for revising, revoking and reissuing, or terminating the pe rmit, or to determine compliance with the permit. Upon request, the Permittee shall also furnish to the Director copies of records required to be kept by the permit. For in formation claimed to be confidential, the Permittee shall furnish an additional copy of such records directly to the Administrator along with a claim of confidentiality.

B. If the Permittee has failed to submit any relevant facts or has submitted incorrect
inform ation in the permit application, the Permittee shall, upon becoming aware of such failure or incorrect submittal, promptly s ubmit such supplementary facts or corrected
information.

XVI. PERMIT AMENDMENT OR REVISION [A.A.C. R18-2-318, -319, and -320]

The Permittee shall apply for a permit amendment or revision for changes to the facility which do not qualify for a facility change without revision under Section XVII, as follows:TV Renewal Permit No. 53399 Page 12 of 109 May 31, 2012 APS-Cholla Generating Station A. Administrative Permit Amendment (A.A.C. R18-2-318);

B. Minor Permit Revision (A.A.C. R18-2-319); and

C. Significant Permit Revision (A.A.C. R18-2-320)

The applicabilit y and requirements for such ac tion are defined in the above referenced regulations.

XVII. FACILITY CHANGE WITHOUT A PERMIT REVISION [A.A.C. R18-2-306.A.4 and -317]

A. The Permittee may make changes at the permitted source without a permit revision if all
of the followi ng apply:

1. The changes are not modifications under any provision of Title I of the Act or under ARS § 49-401.01(24);

2. The changes do not exceed the emissions allowable under the permit whether expressed the rein as a rate of emissions or in terms of total emissions;

3. The changes do not violate any applicable requirem ents or trigger any additional applicable requirements;

4. The changes satisfy all requirements for a minor permit revision under A.A.C.

R18-2-31 9.A; and

5. The changes do not contravene federally enforceable per mit terms and conditions that are monitoring (including test methods), record keeping, reporting, or compliance certification requirements.

B. The substitution of an item of process or pollu tion control equipm ent for an identical or substantially similar item of process or pollution control equipment shall qualify as a change that does not require a permit revision, if it meets all of the requirements of
Conditions XVII.A and XVII.C of this attachment.

C. For each change under Conditions XVII.A and XVII.B above, a written notice by certified mail or hand delivery shall be received by the Director and the Administrator a minimum of 7 working days in advance of the change. Notifications of changes associated with emergency conditions, such as malfunctions necessitating the replacement of equipment, may be provided less than 7 working days in advance of the change, but must be provided as far in advan ce of the change as possible or, if advance notification is not practicable, as soon after the change as possible.

D. Each notification shall include:

1. When the proposed change will occur;

2. A description of the change;

3. Any change in emissions of regulated air pollutants; and

4. Any permit term or condition that is no longer applicable as a result of the change.

E. The permit shield described in A.A.C. R18- 2-325 shall not apply to any change made under this Section, other than implementati on of an alternate to Conditions XVII.A and
XVII.B above.TV Renewal Permit No. 53399 Page 13 of 109 May 31, 2012 APS-Cholla Generating Station F. Except as otherwise provided for in the perm it, making a change from one alternative operating scenario to another as provided under A.A.C. R18-2-306.A.11 shall not require any prior notice under this Section.

G. Notwithstanding any other part of this Section, the Director may require a permit to be revised for any change that, when considered together with any other changes submitted by the same source under this Section over the term of the permit, do not satisfy
Condition XVII.A above.

XVIII. TESTING REQUIREMENTS [A.A.C. R18-2-312]

A. The Permittee shall conduct performance tests as sp ecified in the permit and at such other times as may be required by the Director.

B. Operational Conditions during Testing

Tests shall be conducted during operation at the maximum possible capacity of each unit under representative operational conditions unl ess other conditions are required by the applicable test method or in this permit. With prior written approval from the Director, testing may be performed at a lower rate. Operations during periods of start-up, shutdown, and malfunction (as defined in A.A.C. R18-2-101) shall not constitute representative operational conditions unless ot herwise specified in the applicable
standard.

C. Tests shall be conducted and data reduced in acco rdance with the test methods and procedures contained in the Arizona Testi ng Manual unless modified by the Director pursuant to A.A.C. R18-2-312.B.

D. Test Plan

At least 14 calendar da ys prior to performing a test, the Permittee shall submit a test plan
to the Director in accordance with A.A.C. R 18-2-312.B and the Arizona Testing Manual. This test plan must include the following:

1. Test duration;

2. Test location(s);

3. Test method(s); and

4. Source operation and other parameters th at may affect test results.

E. Stack Sampling Facilities

The Perm ittee shall provide, or cause to be provided, performance testing facilities as
follows:

1. Sampling ports adequate for test methods applicable to the facility;

2. Safe sampling platform(s);

3. Safe access to sampling platform(s); and

4. Utilities for sampling and testing equipment.

F. Interpretation of Final Results

Each perfor mance test shall consist of thr ee separate runs using the applicable test
method. Each run shall be conducted for th e time and under the conditions specified in the applicable standard. For the purpose of determining compliance with an applicableTV Renewal Permit No. 53399 Page 14 of 109 May 31, 2012 APS-Cholla Generating Station standard, the arithmetic mean of the results of th e three runs shall apply. In the event that a sample is accidentally lost or conditions occur in which one of the three runs is required
to be discontinued because of forced shutdow n, failure of an irreplaceable portion of the sample train, extreme meteorological c onditions, or other circumstances beyond the Permittee’s control, compliance may, upon the Director’s approval, be determined using
the arithmetic mean of the results of the other two runs. If the Director or the Director’s designee is present, tests may only be stoppe d with the Director’s or such designee’s approval. If the Director or the Director’s designee is not present, tests may only be stopped for good cause. Good cause includes: forced shutdown, failure of an irreplaceable portion of the sample train, extreme meteorological conditions, or other circumstances beyond the Perm ittee’s control. Termination of any test without good
cause after the first run is commenced shall constitute a failure of the test. Supporting documentation, which demonstrates good cause, must be submitted.

G. Report of Final Test Results

A written report of the results of all performance tests shall be submitted to the Director within 45 days after the test is performed . The report shall be submitted in accordance with the Arizona Testing Manual and A.A.C. R18-2-312.A.

XIX. PROPERTY RIGHTS [A.A.C. R18-2-306.A.8.d]

This permit does not convey any property rights of any sort, or any exclusive privilege.

XX. SEVERABILITY CLAUSE [A.A.C. R18-2-306.A.7]

The provisions of this permit are severable. In th e event of a challenge to any portion of this permit, or if any portion of this permit is he ld invalid, the remaining permit conditions remain
valid and in force.

XXI. PERMIT SHIELD [A.A.C. R18-2-325]

Compliance with the conditions of this permit sh all be deemed compliance with all applicable requirements identified in the portions of this perm it subtitled “Permit Shield”. The permit shield shall not apply to minor revisions pursuant to Condition XVI.B of this attachment and any facility changes without a permit revision pursuant to Section XVII of this attachment.

XXII. PROTECTION OF STRATOSPHERIC OZONE [40 CFR Part 82]

If this source becomes subject to the provisions of 40 CFR Part 82, then the Permittee shall comply with these provisions accordingly.

XXIII. NSPS AND NESHAP REQUIREMENTS [40 CFR Part 60, Part 63]

For all equipment subject to a New Source Pe rformance Standard/National Emissions Standards for Hazardous Air Pollutants, the Permittee shal l comply with all applicable requirements contained in Subpart A of Title 40, Part 60 and Part 63 of the Code of Federal Regulations.TV Renewal Permit No. 53399 Page 15 of 109 May 31, 2012 APS-Cholla Generating Station 

### ATTACHMENT "B": SPECIFIC CONDITIONS

AIR QUALITY CONTROL TI TLE V PERMIT NO. 53399

FOR Arizona Public Service – Cholla Generating Station

I. GENERAL REQUIREMENTS

A. Definitions

1. Startup for Steam Boiler Units 2, 3 and 4: Startup means the setting in operation
of a stea m boiler unit for any purpose. Fo r opacity purposes, startup begins when any forced draft, induced draft, or booster induced draft fan of the unit is turned on for any purpose. [40 CFR 60.2]

2. Shutdown for Steam Boiler Units 2, 3 and 4: Shutdown means the cessation of operation of a steam boiler unit for any purpose. For opacity purposes, shutdown begins when the unit begins to drop load to go off line and ends when all fans of
the unit are turned off. [40 CFR 60.2]

3. Malfunction for Steam Boiler Units 2, 3 and 4: Malfunction means any sudden
and unavoida ble failure of air pollution c ontrol equipment, process equipment or a process to operate in a normal and us ual manner, but does not include failures that are caused by poor maintenance, careless operation or any other upset condition or equipment breakdown which could have been prevented by the
exercise of reasonable care. [40 CFR 60.2]

4. Boiler operating day means a 24-hour period during which fossil fuel is

co mbusted in a steam generating unit for the entire 24 hours. [40 CFR 60.41a]

B. For the purpose of this permit, unless otherwise speci fied in the appli cable standards, for any facility subject to the new source pe rformance standards from 40 CFR Part 60, compliance with such standards other than opacity standards shall be determined in accordance with performance te sts. The performance tests shall be conducted and data
reduced in accordance with the test methods and procedures contained in the subsection “Performance Testing Requirements” of each applicable section. [40 CFR 60.11(a) and 8(b)]

C. For the purpose of this permit, for any fac ility subject to the new source performance
standards from 40 CFR Part 60, compliance with the opacity standards shall be determined by conducting observations in acco rdance with EPA Reference Method 9, or any alternative method that is approved by the Director and the Administrator, unless the Permittee elects to submit continuous opacity monitoring system data for compliance with the opacity standards. [40 CFR 60.11(b)]

D. For the purpose of submitting compliance certifications or establishing whether or not the

Perm ittee has violated or is in violation of any new source performance standards from 40 CFR Part 60, subsumed under this attachment, nothing in this attachment shall preclude the use, including the exclusive use, of any credible evidence or information,
relevant to whether a source would have been in compliance with such standards if the appropriate performance or compliance t est or procedure had been performed. [40 CFR 60.11(g)]TV Renewal Permit No. 53399 Page 16 of 109 May 31, 2012 APS-Cholla Generating Station E. For the purpose of this permit, the EPA Refe rence Method 9 readi ng shall be defined as an average of 24 consecutive opacity observations recorded at 15-second intervals. A set is composed of any 24 consecutive observations . Sets need not be consecutive in time and in no case shall two sets overlap. For each set of 24 observations, calculate the average by summing the opacity of the 24 observations and dividing this sum by 24. [A.A.C. R18-2-306.A.3.c and 40 CFR 60, Appendix A, Method 9, Section 2.5]

F. The Permittee shall have on staff a person that is certified in EPA Reference Method 9.
[A.A.C. R18-2-306.A.3.c]

G. Within fourteen (14) calendar days after th e com pliance certifications required by Section
VII of Attachment "A" have been submitte d, the Permittee shall submit summary reports of all monitoring activities required in this attachment performed in the six months prior to the date of the report. [A.A.C. R18-2-306.A.5.a]

H. For the purposes of this permit, Visible Emissions Observation Procedure shall refer to the following methodology:

1. The Permittee shall continue to comply with the a pproved visual observation plan. The observation plan shall identify a central lookout station or multiple observation points, as appropriate, from where point and/or non-point sources, and where applicable, fugitive emissions, shall be monitored. When multiple observation points are used, all the point and/or non-point sources, and where applicable, fugitive emissions, associated with each observation point shall be specifically identified within the observation plan.

2. A certified EPA Reference Method 9 observe r shall conduct a visual survey of visible emissions from point or non-point sources, and where applicable, fugitive emissions, in accordance with the ob servation plan, under normal representative operating conditions. The survey shall be conducted at the frequency specified in the permit condition that refers to this procedure. The Permittee shall keep a record of the name of the observer, the date and time on which the observation was made, the location(s) of the observation, and the results of the observation.

3. If the observer sees a plume from a point or non-point source or a fugitive

e missions source that on an instantaneous basis appears to exceed the applicable opacity standard, then the observer shall, if practicable, take a six-minute EPA Reference Method 9 observation of the plume.

4. If the six-minute opacity of the plume is less than the applicable opacity standard, the observer shall make a record of the following:

a. Location, date, and time of the observation;

b. The results of the EPA Reference Method 9 observation; and

c. The name of the observer.

5. If the six-minute opacity of the plume ex ce eds the applicable opacity standard, then the Permittee shall do the following:

a. Adjust or repair the controls or e quip ment to reduce opacity to below the applicable opacity standard;

b. Record corrective actions;TV Renewal Permit No. 53399 Page 17 of 109 May 31, 2012 APS-Cholla Generating Station c. Report as an excess emission in accordance with Section XII of
Attach ment “A” of this permit; and

d. Conduct a six-minute EPA Reference Method 9 observation reading within 48 hours after taking corrective action. The results of this observation including date, time, name of the observer, and location shall
be recorded.

6. Any changes to the observation plan shall be made only with the prior approval
of the Director.

I

. The conditions of this attachment shall appl y to equipment identified in Attachment “C” of this permit. In the event that after the date of permit issuance , the Permittee identifies pollutant emitting equipment or air pollution control equipment existing at the plant at the time of permit issuance, but not included in th e permit application for this permit, or if
the Permittee identifies errors in Attachment “C” of this permit, the Permittee shall follow the appropriate administrative procedur es as set forth in Article 3 of Title 18, Chapter 2 of the Arizona Administrative Code to include such equipment in the permit or
to correct such errors. [A.A.C. R18-2-304.G]

II. STEAM BOILER UNIT 1

A Applicability

This section applies to Unit 1 boiler as d escribed in Attachment “C” of this permit.

B. Fuel Limitation

The Perm ittee shall burn only the foll owing fuels in Steam Boiler Unit 1:

1. Coal;

2. Natural Gas for startup and stabilization.

[Installation Permit No. 1002] C. Particulate Matter & Opacity

1. Emission Limits/Standards

a. Opacity

The Permittee shall not cause, allow or permit to be emitted into the atmosphere any plume or effluent from the stack of Steam Boiler Unit 1, the opacity of which exceeds 20 percent, measured in accordance with
EPA Reference Method 9. Where th e presence of uncombined water is the only reason for an exceedance of the visible emissions requirement,
such exceedance shall not constitute a violation. [A.A.C. R18-2-702.B.3 and C]

b. Particulate Matter

The Permittee shall not cause, allow or permit the emission of particulate
matter from the stack of Steam Boiler Unit 1 in excess of the amounts calculated by the following equation and rounded off to two decimal places:

E = 1.02 Q 0.769TV Renewal Permit No. 53399 Page 18 of 109 May 31, 2012 APS-Cholla Generating Station Where:

E = the maximum allowable partic ulate matter emissions rate in pounds-mass per hour

Q = the heat input in million Btu per hour [A.A.C. R18-2-703.C.1 and D]

c. Definition of Heat Input

For the pur pose of Conditions II.C.1.b of this Attachment, “heat input” is defined as the aggregate heat content of all fuels whose products of combustion pass through a stack or other outlet. The heat content of
solid fuel shall be determined in accordance with A.A.C. R18-2-311.
[A.A.C. R18-2-703.B]

2. Air Pollution Control Requirements

The Permittee shall, at all times, including periods of startup, shutdown and malfunction, to the extent practicable, operate and maintain Steam Boiler Unit 1
and the fabric filter control device in a manner consistent with good air pollution control practice for minimizing particulate matter emissions . The Permittee shall inspect and maintain the fabric f ilter control device in accordance with manufacturer specifications. [A.A.C. R18-2-306.A.2 and A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics ]

3. Monitoring & Recordkeeping Requirements

Continuous Monitoring for Opacity

a. The Permittee shall calibrate, maintain, and operate a continuous opacity monitoring system (COMS) for monitoring opacity at the fabric filter baghouse outlet of Steam Boiler Unit 1
[A.A.C. R18-2-313, A.A.C. R18-2-331.A.3.c] [Material Permit Condition identifie d by underline and italics]

b. The COMS shall meet the following requirements under 40 CFR 60, Appendix B, Performance Specification 1, Specification and Test Procedures for Opacity Continuous Emission Monitoring Systems in Stationary Sources [A.A.C. R18-2-313.D.1.a]

(1) Apparatus

(2) Installation Specifications

(3) Design and Performance Specifications

(4) Design Specifications Verification Procedure

(5) Performance Specifications Verification Procedure

(6) Equations

c. Quality Assurance Requirements

i. Calibration Checks

The Per mittee shall record the zer o and span drift in accordanceTV Renewal Permit No. 53399 Page 19 of 109 May 31, 2012 APS-Cholla Generating Station with the method prescribed by the manufacturer's recommended zero and span check at least once daily unless the manufacturer has recommended adjustments at shorter intervals, in which case
such recommendations shall be followed. [A.A.C. R18-2-313.D.6]

ii. Zero and Span Drift Adjustments

(1) The Permittee shall adjust th e zero or span whenever the
24 hour zero drift or 24 hour calibration drift limits of 2% opacity are exceeded. [A.A.C. R18-2-313.D.6]

(2) The system shall allow for the amount of excess zero and span drift measured at the 24-hour interval checks to be recorded and quantified. [A.A.C. R18-2-313.D.6]

(3) The optical surfaces exposed to the effluent gases shall
be clean ed prior to performing the zero and span drift adjustments except that for sy stems using automatic zero adjustments. [40 CFR 60, Appendix B, PS1, 5.1.6]

(4) The optical surfaces shall be cleaned when the

cu mulative automatic zero compensation exceeds 4% opacity. [ 40 CFR 60, Appendix B, PS1, 5.1.7]

iii. Minimum Frequency of Operation

Except durin g periods of system breakdowns, repairs, calibration checks, and zero and span adjustments, the COMS shall be in continuous operation and shall complete a minimum of one cycle of sampling and analyzing for each successive 15-second period and one cycle of data recording for each successive 6- minute period. [A.A.C. R18-2-313.E.2]

iv. Data Reduction Procedures

(1) The Permittee shall reduce all data from the COMS to 6-
minute avera ges. Six-minute opacity averages shall be calculated from 24 or more data points equally spaced over each 6-minute period.

(2) Data recorded during pe r iods of system breakdowns, repairs, calibration checks, and zero and span adjustments shall not be included in the data averages computed under the previous Condition. An arithmetic or integrated average of all data may be used.
[A.A.C. R18-2-313.E]

d. The Permittee shall comply with a ll the recordkeeping requirements of 40 CFR Part 75 Subparts F. [A.A.C. R18-2-306.A.4 and 5] 4. Reporting Requirements

a. Quarterly Reporting Requirements

i. The Permittee shall submit to the Director a written report of all

e mission exceedances for each calendar quarter and the natureTV Renewal Permit No. 53399 Page 20 of 109 May 31, 2012 APS-Cholla Generating Station and cause of the exceedances, if known, postmarked by the 30th day following the end of each calendar quarter. The averaging period used for data reporting shall correspond to the averaging period specified in the emission standard. The required report shall include, as a minimum, the data stipulated in this
subsection. [A.A.C. R18-2-313.E.1]

ii. For opacity measurements, the summary shall consist of the magnitude in actual percent opacity of all six minute opacity averages greater than any applicable standards for each hour of operation of the facility. Average values may be obtained by integration over the averaging period or by arithmetically averaging a minimum of four equally spaced, instantaneous opacity measurements per minute. Any time periods exempted shall be deleted before determining any averages in excess of opacity standards. [A.A.C. R18-2-313.E.2]

iii. The date and time identifying each period during which the
continuo us emission monitoring system was inoperative, except for zero and span checks and the nature of system repair or adjustment shall be reported. The Director may require proof of continuous emission monitoring system performance whenever system repairs or adjustments have been made.
[A.A.C. R18-2-313.E.4] b. Emission Deviations Reporting Requirements

In addition to Condition II.C.4.a above, the Permittee shall report emissions exceeding an emission limitation or standard as deviations in accordance with Section XII.B of Attachment “A” of this permit. [A.A.C. R18-2-306.A.5.b]

c. When no emission exceedances/deviations have occurred and the
continuo us emission monitoring system(s) have not been inoperative, repaired, or adjusted, such informati on shall be included in the quarterly
report. [A.A.C. R18-2-306.A.5.b and 313.E.5]

d. The Permittee shall comply with all reporting requi rements of 40 CFR Part 75 Subparts G. [A.A.C. R18-2-306.A.4 and 5]

5. Performance Testing Requirements

a. Opacity

The Permittee shall perform an annual opacity observation of the stack of
Steam Boiler Unit 1 in accordance with EPA Reference Method 9.
[A.A.C. R18-2-312.A]

b. Particulate Matter

The Permittee shall conduct annual performance test during operation at the nominal rated capacity of the unit using Reference Method 5 listed in Appendices to 40 CFR Part 60 to determine compliance with the particulate matter emissions standard specified in Condition II.C.1.b from
the stack of Steam Boiler Unit 1. [A.A.C. R18-2-311.A, 312.A, 703.B and 703.K]TV Renewal Permit No. 53399 Page 21 of 109 May 31, 2012 APS-Cholla Generating Station 6. Compliance Assurance Monito ring for Particulate Matter

The Permittee shall conduct compliance assurance monitoring as required in Attachment “E” of this permit for Steam Boiler Unit 1. [40 CFR Part 64]

7. Permit Shield

Compliance with the terms of this Sec tion shall be deemed compliance with the applicable requirements prescribed under A. A.C. R18-2-702.B.3, 702.C, 703, for the affected source subject to this Section. [A.A.C. R18-2-325

D. Sulfur Dioxide

1. Emission Limitations/Standards

a. The Permittee shall not cause, allow, or permit emissions of more than 1.0 pounds of sulfur dioxi de maxi mum three hour average, per million Btu (430 nanograms per joule) heat input from the stack of Steam Boiler
Unit 1. [A.A.C. R18-2-703.G.1]

b. The Permittee shall achieve at least 80 percent sulfur dioxide removal efficiency from the Steam Boiler Unit 1 and associated control device on a 30 successive boiler operating day rolling average. [Installation Permit No. 1247, Attachment “B”, Condition II.B]

2. Air Pollution Control Requirements

The Permittee shall, at all times, including periods of startup, shutdown and malfunction, to the extent practicable, operate and maintain Steam Boiler Unit 1
and the tray tower absorber in a manner consistent with good air pollution control practice for minimizing sulfur dioxide emissions . The Permittee shall inspect and maintain the fabric f ilter control device in accordance with manufacturer specifications. [A.A.C. R18-2-306.A.2 and A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

3. Monitoring and Recordkeeping Requirements

Continuous Monitoring for SO 2 and O 2 /CO 2

a. The Permittee shall calibrate, maintain, and operate a continuous emission monitoring systems (CEMS) for measuring sulfur dioxide emissions and diluent oxygen/carbon dioxide ( O 2 /CO 2) at both the inlet and outlet of the sulfur dioxide control device. [A.A.C. R18-2-703.J, A.A.C. R18-2-331.A.3.c] [Material Permit Condi tion identified by underline and italics ]

b. The Permittee shall record SO 2 and O 2 /CO 2 CEMS data during all periods of operation of Steam Boiler Unit 1 including periods of startup, shutdown, malfunction or emergenc y conditions, except for continuous monitoring system breakdown, repairs, calibration checks, and zero and span adjustments. [A.A.C. R18-2-703.J]

c. The continuous emission monitoring systems for SO 2 and O 2 /CO 2 shall meet the following requirements: [A.A.C. R18-2-313]TV Renewal Permit No. 53399 Page 22 of 109 May 31, 2012 APS-Cholla Generating Station i. 40 CFR Part 75, Appendix A, “Specification and Test
Procedures”

(1) Installation and measurement location

(2) Equipment specifications

(3) Performance specifications

(4) Data acquisition and handling systems

(5) Calibration gas

(6) Certifications tests and procedures

(7) Calculations

ii. 40 CFR Part 75, Appendix B, “Quality Assurance and Quality
Control Proce dure”

(1) Quality control program

(2) Frequency of testing

iii. Data Reduction

The Per mittee shall comply with the data reduction requirements of 40 CFR Part 75.10(d)(1).

iv. 40 CFR Part 75, Appendix F, “Conversion Procedures”

The Permittee shall convert all hourly pollutant and diluent data to the applicable emissions standard utilizing the procedures of 40 CFR Part 75, Appendix F.

d. Sulfur Dioxide Emissions Missing Data Supplemental Procedures
[A.A.C. R18-2-306.A.3.c]

The Permittee shall obtain the SO 2 emission data for at least 18 hours in at least 22 out of 30 successive boiler operating days. If this minimum data requirement cannot be met with the continuous monitoring system in use, the Permittee shall supplement SO 2 emission data with other monitoring systems approved by the Director or the following reference methods and procedures:

i. Reference Method 6 shall be used to determine the SO 2 concentration at the same location as the SO 2 monitor.

ii. The emission rate correction factor, integrated bag sampling and analy sis procedure of Reference Method 3B shall be used to
determine the O 2 /CO 2 concentration at the same location as the
O 2 /CO 2 monitor.

iii. The procedures in Reference Method 19 shall be used to

co mpute each 1-hour average concentration in ng/J (pounds per million Btu).TV Renewal Permit No. 53399 Page 23 of 109 May 31, 2012 APS-Cholla Generating Station iv. As alternatives, the referen ce methods and procedures described in 40 CFR 49Da(j) may be used.

e. The Permittee shall comply with a ll the recordkeepi ng requirements of 40 CFR Part 75 Subparts G. [A.A.C. R18-2-306.A.4]

4. Reporting Requirements

a. Quarterly Reporting Requirements

i. The Permittee shall submit to the Director a written report of all

e mission exceedances for each calendar quarter and the nature and cause of the exceedances, if known, postmarked by the 30th day following the end of each calendar quarter. The averaging period used for data reporting shall correspond to the averaging period specified in the emission standard. The required report shall include, as a minimum, the data stipulated in this
subsection. [A.A.C. R18-2-313.E.1]

ii. For gaseous measurements the summary shall consist of

e mission averages in the units of the applicable standard for each averaging period during which the applicable standard was
exceeded. [A.A.C. R18-2-313.E.3]

iii. For SO 2 removal efficiency, the summary shall include the 30- day rolling average of the removal efficiency for each day in the
quarter. [Installation Permit No. 1247]

iv. The date and time identifying each period during which the
continuo us emission monitoring system was inoperative, except for zero and span checks and the nature of system repair or adjustment shall be reported. The Director may require proof of continuous emission monitoring system performance whenever system repairs or adjustments have been made.
[A.A.C. R18-2-313.E.4] b. Emission Deviations Reporting Requirements

In addition to Condition II.D.4.a above, the Permittee shall report emissions exceeding an emission limitation or standard as deviations in accordance with Section XII.B of Attachment “A” of this permit. [A.A.C. R18-2-306.A.5.b]

c. When no emission exceedances/deviations have occurred and the
continuo us emission monitoring system(s) have not been inoperative, repaired, or adjusted, such informati on shall be included in the quarterly
report. [A.A.C. R18-2-306.A.5.b and 313.E.5]

d. The Permittee shall comply with all the reporting requirem ents of 40 CFR Part 75 Subparts G. [A.A.C. R18-2-306.A.5]

5. Performance Testing Requirements

a. The Permittee use the applicable reference methods given in the Appendices to 40 CFR Part 60 to determine compliance with the standard
of sulfur dioxide emissions from th e stack of Steam Boiler Unit 1, asTV Renewal Permit No. 53399 Page 24 of 109 May 31, 2012 APS-Cholla Generating Station specified in Condition II.D.1.a of this Attachment. The performance test using such reference methods sha ll be conducted annually and during operation at the nominal rated capacity of the unit. [A.A.C. R18-2-311.A, 312.A, 703.B and 703.K]

b. To determine compliance with th e 30 successive boiler operating day rolling average SO 2 removal efficiency specified in Condition II.D.1.b of this Attachment, the Permittee sha ll calculate average daily removal efficiency using the 1-hour average CEMS data and Reference Method
19. The Permittee shall accumula te the average daily removal efficiencies at the end of each boiler operating day for the last 30 successive boiler operating days to calculate the 30-day rolling average removal efficiency and to determine compliance with the standard of 80% removal efficiency. [A.A.C. R18-2-306.A.3.c]

c. The Permittee shall obtain SO 2 emission data for at least 18 hours in at least 22 out of 30 successive boiler operating days. If the Permittee has not obtained the required minimum quantity of data, compliance of
Steam Boiler Unit 1 with the SO 2 emission requirements under Condition II.D.1.b of this Attachment for the day on which the 30-day period ends shall be determined by following th e applicable procedures in Section 7
of EPA Reference Method 19.
[A.A.C. R18-2-306.A.3.c] 6. Permit Shield

Compliance with the terms of this Sec tion shall be deemed compliance with the applicable requirements prescribed under A.A.C. R18-2-703.G.1 and Installation Permit #1247 for the affected source subject to this Section.
[A.A.C. R18-2-325] E. Nitrogen Oxides

1. Air Quality Control Requirements

At all times including periods of startup, shutdown a nd malfunction, to the extent practicable, the Permittee shall operate and maintain Steam Boiler Unit 1 and
associated low NO

x burners in a manner consistent with good air pollution control practice for minimizing nitrogen oxides emissions . The Permittee shall inspect and maintain the fabric filter control device in accordance with manufacturer specifications. [A.A.C. R18-2-306.A.2 and A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

F. Carbon Monoxide

1. Emission Limits/Standards

a. At all times, excluding periods of startup and shutdown, the Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 1, any gases which contain carbon monoxide in excess
of:

i. 0.15 lb per million Btu heat input derived from combustion of fuel, based on a 30-da y rolling average. [A.A.C. R18-2-406.A.4]

ii. 0.75 lb per million Btu heat input derived from combustion of fuel, on an hourly basis. [A.A.C. R18-2-406.A.5]TV Renewal Permit No. 53399 Page 25 of 109 May 31, 2012 APS-Cholla Generating Station b. During periods of startup and shutdown, the Permittee shall not cause to be discharged into the atmosphere fro m the stack of Steam Boiler Unit 1, any gases which contain carbon monoxide in excess of 250 pounds per
hour. [A.A.C. R18-2-406.A.5]

2. Air Quality Control Requirements [A.A.C. R18-2-406.A.4]

a. At all times, including periods of startup, shutdown and malfunction, to the extent practicable, the Permittee shall operate and maintain Steam
Boiler Unit 1 and associated low NO

x burners in a manner consistent with good combustion practices fo r minimizing carbon monoxide

emissions

. A.A.C. R18-2-306.A.3.a, 331.A.3.c and 406.A.4] [Material Permit Condition identified by underline and italics]

b. For the purpose of this Section, the good combustion practices shall include, but is not limited to, the following components:

i. Good air/fuel mixing in the combustion zone;

ii. High temperatures and low oxygen levels in the primary

co mbustion zone;

iii. Overall excess oxygen levels high enough to complete

co mbustion while maximizing boiler thermal efficiency; and

iv. Sufficient residence time to complete combustion.

c. Determination of whether the good combustion practices are being implemented for minimizing boiler carbon monoxide emissions will be
based on information available to th e Director which may include, but not limited to, monitoring results, re view of operation and maintenance procedures and records, and inspection of the source.

3. Monitoring, Recordkeeping and Reporting Requirements

a. The Permittee shall install, calibrate , maintain, and operate a continuous emission monitoring system (CEMS) at each affected steam boiler unit

, and record the output of the system, for measuring carbon monoxide (CO) and diluent (O 2 /CO 2 ) emissions from exhaust of the boiler’s stack

. The output of the CEMS shall be expressed in pounds CO per million Btu heat input.
[ A.A.C. R18-2-306.A.3.a, 331.A.3.c and 406.A.4] [Material Permit Condition identified by underline and italics]

b. The existing diluent (O 2 /CO 2 ) continuous monitoring systems required under Sections III.E.3, IV.E.3 or V.E.3 of Attachment “B” of the permit may be used to satisfy the require ment for monitoring of diluent
emissions.

c. All continuous monitoring systems shall meet the following requirem ents: [A.A.C. R18-2-306.A.3.a and 406.A.4]

i. 40 CFR Part 75, Appendix A "Specification and Test
Procedures" for installation of the NO

x monitor shall be used for CO monitor by substituting NO

x for CO. Due to normalTV Renewal Permit No. 53399 Page 26 of 109 May 31, 2012 APS-Cholla Generating Station combustion variability, a dual range CO monitor shall be installed. The RATA specification shall be measured with 2 decimal places in lb CO per million BTU.

ii. 40 CFR Part 75, Appendix A, “Specification and Test
Procedures” f or CO and O 2 /CO 2 monitors

(1) Installation and measurement location

(2) Equipment specifications

(3) Performance specifications

(4) Data acquisition and handling systems

(5) Calibration gas

(6) Certifications tests and procedures

(7) Calculations

iii. 40 CFR Part 75, Appendix B, “Quality Assurance and Quality
Control Proce dure”

(1) Quality assurance/quality control program

(2) Frequency of testing

iv. 40 CFR Part 60 Appendix “F”, Quality Assurance Procedure for CO monitor for determining with pounds per hour emission rate
under Condition XIV.A.2 of this Attachment.

v. Data Reduction

The Permittee shall comply with the data reduction requirements of 40 CFR Part 75.10(d)(1).

vi. Missing Data Substitution

(1) The Permittee shall, in processing any CO emission data gaps throu ghout operation, comply with the appropriate provisions in 40 CFR Part 75, Subpart D, “Missing Data
Substitution Procedures” and Appendix C, “Missing Data Estimation Procedures”. For the purpose of this Section, when monitor data availability reaches below 80%, all CO emission data ga ps shall be substituted using a CO emission rate not less than 0.75 lb per million Btu heat input derived from combustion of fuel.

(2) The Permittee may elect to supplement CO emission data
with the fo llowing USEPA reference methods and procedures:

(a) Reference Method 10 shall be used to determine
the CO conce ntration at the same location as the
CO monitor.

(b) The emission rate correction factor, integrated bag sam pling and analysis procedure ofTV Renewal Permit No. 53399 Page 27 of 109 May 31, 2012 APS-Cholla Generating Station Reference Method 3B shall be used to determine
the O 2 /CO 2 concentration at the same location as
the O 2 /CO 2 monitor.

(c) The procedures in Reference Method 19 shall be
used to com pute each 1-hour average concentration in ng/J (pounds per million Btu).

(d) As Method 19 does not provide conversion
factors for carbon m onoxide, a conversion factor
of 7.269×10 -8 shall be used to convert parts per million (ppm) to pounds per standard cubic foot (lb/scf).

vii. 40 CFR Part 75, Appendix F, “Conversion Procedures”

The Perm ittee shall convert all hour ly pollutant and diluent data to the applicable emissions sta ndard utilizing the procedures of 40 CFR Part 75, Appendix F.

d. Except for system breakdowns, repair s, calibration checks, and zero and span adjustments, each continuous m onitoring system prescribed in this Section shall complete a minimum of one cycle of operation (sampling, analyzing, and data recording) for each successive 15-minute period. [A.A.C. R18-2-306.A.3.a and 406.A.4]

e. CO Emissions Compliance Determination [A.A.C. R18-2-406.A.4 and 5]

i. The Permittee shall use CO emission data measured and recorded by the continuous m onitoring systems prescribed in this Section to demonstrate compliance with the carbon
monoxide emission standards set forth in Condition XIV.A of
this Attachment.

ii. Compliance with Condition II.F.1.a.i of this Attachment shall be based on the average e mission rate for 30 successive calendar days. A new 30-day average carbon monoxide emission rate shall be determined at the end of each calendar day by calculating the arithmetic average of all hourly carbon monoxide emission rates for the past 30 successive calendar days, except for data obtained during periods of startup, shutdown, or
malfunction.

iii. The following shall be consid ered periods of excess emissions:

(1) Any calendar day for which the 30-day rolling average
CO emissio n rate, excluding periods of startup, shutdown, or malfunction, as determined by the applicable continuous monitoring systems in accordance with Condition II.F.3.e.ii above exceeds the 30-day average CO emission limit set forth in Condition
II.F.1.a.i of this Attachment.

(2) Any hour for which the hourly CO emission rate, excluding periods of startup, shutdown or malfunction, as measured by the applicable continuous monitoring systems of this Section exceeds the hourly CO emission
limit set forth in Condition II.F.1.a.ii of this Attachment.TV Renewal Permit No. 53399 Page 28 of 109 May 31, 2012 APS-Cholla Generating Station (3) Any periods of startup, shutdown or malfunction, for which the CO emissions rate for any unit exceeds the
emission limit set forth in Condition II.F.1.b of this
Attachment.

iv. All excess emissions shall be reported in accordance with Section XII, Attach ment “A” of the permit. [A.A.C. R18-2-306.A.5.b and 310.01]

f. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monito ring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other in formation required by this part recorded in a permanent form suitable for inspection. The file shall be retained for at least five years follo wing the date of such measurements, maintenance, reports, and records. [A.A.C. R18-2-306.A.4.a and 406.A.4]

III. STEAM BOILER UNIT 2

A. Applicability

This section applies to Unit 2 boiler as d escribed in Attachment “C” of this permit.

B. Fuel Limitation

The Perm ittee shall burn only the foll owing fuels in Steam Boiler Unit 2:

1. Coal;

2. No. 2 fuel oil for startup and stabilization. [Installation Permit No. 1037] C. Operation Procedures

1. Startup

a. The Permittee shall place in service, th e Venturi scrubbers and absorbers of the unit within one hour of startup of the boiler-induced draft fans and forced draft fans and before fires are in the boiler.

b. Upon installation of the lime slurry Flue Gas Desulfurization (FGD) system on Unit 2, during startups the fabric filter shall be placed in service before startup of any boiler forced draft or induced draft fan. The fabric filter may be removed from service just prior to igniting oil fires (startup fuel) but must be returned to service before coal fires are placed in the boiler. The FGD system shall be placed in service after the fabric filter is placed in service, and before coal fires are in the boiler

. [40 CFR 60.11(d) and A.A.C. R18-2-331.A.3.e] [Material Permit Condi tion identified by underline and italics ] 2. Shutdown

a. The Permittee shall keep the Venturi scrubbers and absorbers of the unit in service after fires in the boiler are out and shall not be taken out of service until just prior to the boiler fo rced draft fans and induced draft fans being turned off.TV Renewal Permit No. 53399 Page 29 of 109 May 31, 2012 APS-Cholla Generating Station b. Upon installation of the lime slurry Flue Gas Desulfurization (FGD) system on Unit 2, during shutdowns the fabric filter shall remain in service until after the boiler forced draft fans and induced draft fans have been turned off. The FGD system s hall remain in service until coal fires
in the boiler are out

. [40 CFR 60.11(d), A.A.C. R18-2-331.A.3.a] [Material Permit Condition identified by underline and italics]

3. Malfunction

a. Any malfunction of the Venturi scrubbers unit that exceeds four hours, and if fires are in the boiler, the Pe rmittee shall reduce the unit’s load so that the Venturi scrubbers in service can properly process and treat the volume of flue gas being produced. If a malfunction makes it impossible to properly process and treat the volum e of flue gas being produced, the
unit shall be shut down. [40 CFR 60.11(d)]

b. Any malfunction of the FGD unit that exceeds four hours, and if fires are in the boiler, the Permittee shall reduce the unit’s load so that the FGD in service can properly process and trea t the volume of flue gas being produced. If a malfunction makes it impossible to properly process and treat the volume of flue gas being produced, the unit shall be shut down. [40 CFR 60.11(d)]

4. Emergency [PSD Permit No. M170843S1-98]

During emergency conditions as defined in 40 CFR 60.41Da, Steam Boiler Unit 2 with a malfunctioning flue gas desulfurization (FGD) system may be operated if sulfur dioxide emissions are minimized by:

a. Operating all operable flue gas desulfurization system modules, and bringing back into operation any malfunctioned module as soon as repairs are completed; [40 CFR 60.48Da(d)(1), A.A.C. R18-2-331.A.3.a] [Material Permit Condition identifie d by underline and italics]

b. Bypassing flue gases around only those flue gas desulfurization system modules that have been taken out of operation because they were incapable of any sulfur dioxide emission reduction or which would have suffered significant physical damage if they had remained in operation ; and [40 CFR 60.48Da(d)(2), A.A.C. R18-2-331.A.3.a] [Material Permit Condition identifie d by underline and italics]

c. Designing, constructing, and operating a spare FGD system module for
Steam Boiler Unit 2 , the Permittee shall demonstrate the capability of the spare FGD system in accord ance with 40 CFR 60.48Da(d)(3). [40 CFR 60.48Da(d)(3), A.A.C. R18-2-331.A.3.a] [Material Permit Condition identified by underline and italics]

D. Particulate Matter & Opacity

1. Emission Limits/Standards

a. Opacity

The opacity of emissions from the st ack of Steam Boiler Unit 2 shall not be greater than 20 percent at all times except for periods of startup,TV Renewal Permit No. 53399 Page 30 of 109 May 31, 2012 APS-Cholla Generating Station shutdown, and malfunction as defined in Conditions I.A.1, 2 and 3 of this Attachment, and for one six-minute period per hour of not more than 27 percent opacity. Opacity readings of portions of plumes which contain condensed, uncombined water vapor shall not be used for purposes of determining compliance with the opacity standard

. [40 CFR 60.42(a)(2), 60.11(c) and 60.11(e)(1), A.A.C. R18-2-331.A.3.a] [Material Permit Condition identified by underline and italics]

b. Particulate Matter

The Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 2, any gases which contain particulate matter in excess of 43 nanogram per joule heat input (0.10 lb per million Btu) derived from fossil fuel. [40 CFR 60.42(a)(1)]

2. Air Pollution Control Requirements

a. Until the installation of fabric filters on Unit 2, the Permittee shall at all times, including periods of startup, shutdown, and malfunction and to the extent practicable, continue to operate and maintain Steam Boiler Unit 2
and its mechanical dust collectors and Venturi scrubbers in a manner consistent with good air pollution control practice for minimizing particulate matter emissions . The Permittee shall inspect and maintain
the dust collectors and scrubbers in accordance with manufacturer specifications. [40 CFR 60.11(d) and A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics ]

b. Upon the installation of the fabric filters on Unit 2, the Permittee shall at all times, including periods of startup, shutdown, and malfunction and to the extent practicable, continue to operate and maintain Steam Boiler
Unit 2 and the fabric filter control device in a manner consistent with good air pollution control practice for minimizing particulate matter

emissions . The Permittee shall inspect and maintain the fabric filter control device in accordance with manufacturer specifications. [40 CFR 60.11(d) and A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

3. Monitoring, Recordkeepin g & Reporting Requirements

Continuous Monitoring for Opacity

a. The Permittee shall calibrate , maintain, and operate a continuous opacity monitoring system (COMS) at the f abric filter outlet for measuring the opacity of emissions. [40 CFR 60.45(a), A.A.C. R18-2-331.A.3.c] [Material Permit Condi tion identified by underline and italics]

b. The COMS shall meet the following requirements:

i. 40 CFR 60, Appendix B, Performance Specification 1, “Specificatio n and Test Procedures for Opacity Continuous Emission Monitoring Systems in Stationary Sources”
[40 CFR 60.13] (1) Apparatus

(2) Installation Specifications

(3) Design and Performance SpecificationsTV Renewal Permit No. 53399 Page 31 of 109 May 31, 2012 APS-Cholla Generating Station (4) Design Specifications Verification Procedure

(5) Performance Specifications Verification Procedure

(6) Equations

ii. Quality assurance requirements:

(1) Calibration Checks

The Perm ittee shall check the zero (or low-level value between 0 and 20% of span value) and span calibration drifts at least once daily in accordance with a written procedure. [40 CFR 60.13(d)(1)]

(2) Zero and Span Drift Adjustments

(a) The zero and span shall, as a minimum, be adjusted whenever the 24-hr zero drift or 24-hr span drift exceeds 4% opacity. [40 CFR 60.13(d)(1)]

(b) The system shall allow for the amount of excess zero and span drift m easured at the 24-hour interval checks to be recorded and quantified. [40 CFR 60.13(d)(1)]

(c) The optical surfaces exposed to the effluent gases shall b e cleaned prior to performing the zero and span drift adjustments, except for systems using automatic zero adjustments. [40 CFR 60.13(d)(1)]

(d) For systems using automatic zero adjustments, the optical surfaces shall be cleaned when the cumulative automatic zero compensation exceeds 4% opacity. [40 CFR 60.13(d)(1)]

(3) System Checks

A method for producing a simulated zero opacity condition and an upscale (span) opacity condition using a certified neutral density filte r or other related technique to produce a known obscuration of the light beam to provide a system check of the analyzer internal optical surfaces and all electronic circuitry including the lamp and photo detector assembly shall be used by the
Permittee. [40 CFR 60.13(d)(2)]

(4) Minimum Frequency of Operation

Except during periods of system breakdowns, repairs, calibration checks, and zero and span adjustments, the COMS shall be in continuous operation and shall complete a minimum of one cycle of sampling and analyzing for each successive 10-second period and oneTV Renewal Permit No. 53399 Page 32 of 109 May 31, 2012 APS-Cholla Generating Station cycle of data recording for each successive 6-minute period. [40 CFR 60.13(e)(1)]

(5) Data Reduction Procedures [40 CFR 60.13(h)]

(a) The Permittee shall reduce all data from the
COMS to 6-minute averages. Six-minute opacity averages shall be calculated from 36 or more data points equally spaced over each 6- minute period.

(b) Data recorded during periods of system breakdowns, repairs, calibration checks, and zero and span adjustments shall not be included in the data averages computed under the previous Condition. An arithmetic or integrated average of all data may be used.

4. Recordkeeping and Reporting Requirements

a. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monitoring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other information required by this section recorded in a permanent form suitable for inspection. The file shall be retained for at least five years following the date of such measurements, maintenance, reports and records. [40 CFR 60.7(f)]

b. The Permittee shall comply with all t he recordkeeping and reporting requirements specified in 40 CFR Part 75 Subparts F and G, respectively.
[40 CFR 60.7]

c. The Permittee shall record in a perm anent log for each shutdown, the date and time Steam Boiler Unit 2 intends to begin dropping load to go off line. The log shall be retained fo r at least five (5) years following the
date of each shutdown. [A.A.C. R18-2-306.A.4]

d. Quarterly Excess Emissions and Monitoring System Performance Reports

i. The Permittee shall submit an excess emissions and monitoring systems performance (MSP) report and/or a summary report form to the Department for every calendar quarter, unless the
total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting period and the continuous monitoring system downtime for the reporting period is less than 5 per cent of the total operating time for the reporting period, in which case only the summary report
form shall be submitted and the excess emissions report need not be submitted unless requested by the Department. All quarterly reports shall be postmarked by th e 30th day following the end of each calendar quarter. [40 CFR 60.7(c), & (d), 60.45(g), 60.51Da(j) and 60.51Da(k)]TV Renewal Permit No. 53399 Page 33 of 109 May 31, 2012 APS-Cholla Generating Station ii. The summary report form submission required in the preceding
Condition III.D.4.d.i shall be in the for mat specified in 40 CFR 60.7(d). Each excess emission and MSP report shall include the following information: [40 CFR 60.7(c)]

(1) The magnitude of excess emissions computed, any
conversion f actor(s) used, and the date and time of commencement and completion of each time period of excess emissions. The process operating time during the reporting period.

(2) Specific identification of each period of excess

e missions that occurs duri ng startups, shutdowns, and
malfunctions of the steam boiler unit. The nature and cause of any malfunction (if known), the corrective action taken or preventative measures adopted.

(3) The date and time identifying each period during which
the contin uous monitoring system was inoperative except for zero and span checks and the nature of the system repairs or adjustments.

(4) When no excess emissions have occurred or the
continuo us monitoring system(s) have not been inoperative, repaired, or adjusted, such information shall be stated in the report.
e. Definitions

Opacity excess emissions are defined as any six-minute period during which the average opacity of emissions from Steam Boiler Unit 2 stack exceeds 20 percent opacity as measured by a continuous opacity monitor, except that one six-minute average per hour of up to 27 percent opacity need not be reported. [40 CFR 60.45(g)(1)]

f. Emission deviations reporting requirements

In addition to the quarterl y repor ting required under Condition III.D.4.d above, the Permittee shall report em issions exceeding an emission
limitation or standard as deviations in accordance with Section XII.B of Attachment “A” of this permit. [A.A.C. R18-2-306.A.5.b]

5. Performance Testing Requirements

a. Opacity

The Permittee shall perform an annual opacity observation of the stack of
Steam Boiler Unit 2 in accordance with EPA Reference Method 9. [40 CFR 60.8(a) and 46(b)(3)] b. Particulate Matter

The Permittee shall perform annual performance tests for particulate matter emissions from the stack of Steam Boiler Unit 2, using the following reference methods and procedures: [40 CFR 60.8(a)]TV Renewal Permit No. 53399 Page 34 of 109 May 31, 2012 APS-Cholla Generating Station i. Reference Method

EPA Reference Method 5 or 5B hall be used to determine the particulate matter concentration (C) at the stack of Steam Boiler
Unit 2. [40 CFR 60.46(b)(2)]

ii. Emission Rate

For the purpose of compliance determination, the emission rate (E) of PM shall be computed for each run using the following equation: [40 CFR 60.46(d)(1)]

E = C Fd (20.9)/(20.9 - %O 2 )

Or

E = C F

c (100/%CO 2 )

E = emission rate of pollutant, ng/J (1b/million Btu).

C = concentration of pollutant, ng/dscm (1b/dscf).

%O 2 = oxygen concentration, percent dry basis.

%CO 2 = carbon monoxide concentration, percent dry basis.

Fd = factor as determined from Method 19

F
c = factor as determined in a ppropriate sections of Method 19.

iii. The Permittee may conduct the annual performance tests using alternatives described in 40 CFR 60.46(d).

6. Compliance Assurance Monito ring for Particulate Matter

The Permittee shall conduct the complia nce assurance monitoring required in Attachment “E” of this permit for Steam Boiler Unit 2. [40 CFR Part 64]

7. Permit Shield

Co mpliance with the terms of this Sec tion shall be deemed compliance of the affected sources subject to this Section with the applicable requirements prescribed under 40 CFR 60.42, 40 CFR 60.42, 40 CFR 60.45, 40 CFR 60.46, 40 CFR 60.46, 40 CFR 60.46, and 40 CFR Part 64. [A.A.C. R18-2-325]

E. Sulfur Dioxide Standard

1. Emission Limitations/Standards

a. The Permittee shall not cause to be discharged into the atmosphere from
Stea m Boiler Unit 2 any gases which contain sulfur dioxide in excess of 0.8 pounds per million Btu heat input; and [PSD Permit No. M170843S1-98, Attach ment “B”, Condition XII.B.1]TV Renewal Permit No. 53399 Page 35 of 109 May 31, 2012 APS-Cholla Generating Station b. The Permittee shall not cause to be discharged into the atmosphere from
Stea m Boiler Unit 2, any gases which contain sulfur dioxide in excess of 10 percent of the potential combustion concentration (90 percent
reduction ). [PSD Permit No. M170843S1-98, Attachment “B”, Condition XII.B.1]

c. The sulfur dioxide emission standards required under Conditions
III.E.1.a and b above shall apply at all times except during periods of startup, shutdown, or when emergency conditions, as defined in 40 CFR 60.41Da, exist and emergency procedures under Condition III.C.4 of this Attachment are implemented. [PSD Permit No. M170843S1-98]

2. Air Pollution Control Requirements

a.. Until the installation of lime slurry Flu e Gas Desulfurization (FGD), the Permittee shall at all times, including periods of startup, shutdown, and malfunction and to the extent practicable, continue to operate and
maintain Steam Boiler Unit 2 and its lime thiosulfate Venturi flooded disc scrubbers (Venturi scrubbers) and absorbers in a manner consistent with good air pollution control practice for minimizing sulfur dioxide

emissions . The Permittee shall inspect and maintain the scrubbers and absorbers in accordance with manufacturer specifications. [40 CFR 60.11(d) and PSD Permit No. M170843S1-98, Attachment “B”, Condition XVI and A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

b. Upon the installation of lime slurry Flue Gas Desulfurization (FGD), following, the Permittee shall at all times, including periods of startup, shutdown, and malfunction and to the extent practicable, continue to

operate and maintain Steam Boiler Unit 2 and the lime slurry FGD in a manner consistent with good air pollution control practice for minimizing sulfur dioxide emissions . The Permittee shall inspect and
maintain the FGD control device in accordance with manufacturer specifications. [40 CFR 60.11(d) and PSD Permit No. M170843S1-98, Attachment “B”, Condition XVI and A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics] 3. Monitoring Requirements

Continuous Monitoring for SO 2 and O 2 /CO 2 [PSD Permit No. M170843S1-98, A ttachment “B”, Condition XV.A]

a. The Permittee shall calibrate , maintain, and operate a CEMS, and record the output of the system, for measuring sulfur dioxide emissions. The sulfur dioxide emissions shall be monitored at both the inlet and outlet of the sulfur dioxide control device

. [Material Permit Condition identified by underline and italics]

b. The Permittee shall calibrate , maintain, and operate a continuous monitoring system, and record the output of the system, for measuring
the O 2 /CO 2 content of the flue gases at each location where SO 2 emissions are monitored. [40 CFR 60.49Da(d), A.A.C. R18-2-331.A.3.c] [Material Permit Condi tion identified by underline and italics]

c. The Permittee shall operate the SO 2 and O 2 /CO 2 continuous monitoring systems and record data during all periods of operation of Steam Boiler Unit 2 including periods of startup, shutdown, malfunction or emergencyTV Renewal Permit No. 53399 Page 36 of 109 May 31, 2012 APS-Cholla Generating Station conditions, except for continuous mon itoring system breakdown, repairs, calibration checks, and zero and span adjustments. [40 CFR 60.49Da(e)]

d. The Permittee shall obtain the SO 2 emission data for at least 18 hours in at least 22 out of 30 successive boiler operating days. [40 CFR 60.49Da(f)]

e. The continuous emission monitoring systems for SO 2 , and O 2 /CO 2 shall meet the following requirements:

i. 40 CFR Part 75, Appendix A, “Specification and Test
Procedures” [40 CFR 60.13]

(1) Installation and measurement location

(2) Equipment specifications

(3) Performance specifications

(4) Data acquisition and handling systems

(5) Calibration gas

(6) Certifications tests and procedures

(7) Calculations

ii. 40 CFR Part 75, Appendix B, “Quality Assurance and Quality
Control Proce dure” [40 CFR 60.13]

(1) Quality control program

(2) Frequency of testing

iii. Data Reduction [40 CFR 60.13(h)]

The Permittee shall comply with the data reduction requirements of 40 CFR Part 75.10(d)(1).

iv. 40 CFR Part 75, Appendix F, “Conversion Procedures”
[A.A.C. R18-2-306.A.3.a]

The Permittee shall convert all hourly pollutant and diluent data to the applicable emissions standard utilizing the procedures of 40 CFR Part 75, Appendix F.

f. Sulfur Dioxide Emissions Missing Data Supplemental Procedures [40 CFR 60.49Da(f), (h) a nd (j) and PSD Permit No. M170843S1-98, Attachment “B”, Condition XV.A]

If the minimum data requirement sp ecified in Condition III.E.3.d above cannot be met with the continuous monitoring system in use, the Permittee shall supplement SO 2 emission data with other monitoring systems approved by the Director or the following reference methods and procedures:TV Renewal Permit No. 53399 Page 37 of 109 May 31, 2012 APS-Cholla Generating Station i. Reference Method 6 shall be used to determine the SO 2 concentration at the same location as the SO 2 monitor.

ii. The emission rate correction factor, integrated bag sampling and analy sis procedure of Reference Method 3B shall be used to
determine the O 2 /CO 2 concentration at the same location as the
O 2 /CO 2 monitor.

iii. The procedures in Reference Method 19 shall be used to

co mpute each 1-hour average concentration in ng/J (pounds per million Btu).

iv. As alternatives, the referen ce methods and procedures described in 40 CFR 49Da(j) may be used.

4. Recordkeeping and Reporting Requirements

a. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monitoring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other information required by this section recorded in a permanent form suitable for inspection. The file shall be retained for at least five years following the date of such measurements, maintenance, reports and records. [40 CFR 60.7(f)]

b. The Permittee shall comply with all t he recordkeeping and reporting requirements specified in 40 CFR Part 75 Subparts F and G, respectively.
[40 CFR 60.7]

c. The Permittee shall record in a perm anent log for each shutdown, the date and time Steam Boiler Unit 2 intends to begin dropping load to go off line. The log shall be retained fo r at least five (5) years following the
date of each shutdown. [A.A.C. R18-2-306.A.4]

d. Quarterly excess emissions and monitoring system performance reports

i. The Permittee shall submit an excess emissions and monitoring systems performance (MSP) report and/or a summary report form to the Department for every calendar quarter, unless the
total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting period and the continuous monitoring system downtime for the reporting period is less than 5 per cent of the total operating time for the reporting period, in which case only the summary report
form shall be submitted and the excess emissions report need not be submitted unless requested by the Department. All quarterly reports shall be postmarked by th e 30th day following the end of each calendar quarter. [40 CFR 60.7(c) and (d), 45(g), 51Da(j) and 51Da(k)]

ii. The summary report form submission required in the preceding Condition III.E.4.d shall be in the format specified in 40 CFRTV Renewal Permit No. 53399 Page 38 of 109 May 31, 2012 APS-Cholla Generating Station 60.7(d). Each excess emission and MSP report shall include the following information: [40 CFR 60.7(c)]

(1) The magnitude of excess emissions computed, any
conversion f actor(s) used, and the date and time of commencement and completion of each time period of excess emissions. The process operating time during the reporting period.

(2) Specific identification of each period of excess

e missions that occurs duri ng startups, shutdowns, and
malfunctions of the steam boiler unit. The nature and cause of any malfunction (if known), the corrective action taken or preventative measures adopted.

(3) The date and time identifying each period during which
the contin uous monitoring system was inoperative except for zero and span checks and the nature of the system repairs or adjustments.

(4) When no excess emissions have occurred or the
continuo us monitoring system(s) have not been inoperative, repaired, or adjusted, such information shall be stated in the report.

e. Excess Emissions Definition

Unless otherwise specified, SO 2 excess emissions are defined as any 30 successive boiler operating days for which, except for data obtained during startup, shutdown, or emergency conditions, the arithmetic average of all hourly emission rates for sulfur dioxide exceeds the applicable standard of 0.8 pounds per million Btu heat input, or the percentage sulfur dioxide reduction falls below the applicable standard of 90 percent, as required in Condition III.E.1 of this attachment. The percentage sulfur dioxide reduction is determined based on the average inlet and average outlet SO 2 emission rates for the 30 successive boiler operating days. [40 CFR 60.48Da(e), (g) and PSD Permit No. M170843S1-98, Att achment “B”, Condition XII.A]

f. Emission deviations reporting requirements

In addition to the quarterly reporting required under Condition III.E.4.d above, the Permittee shall report em issions exceeding an emission
limitation or standard as deviations in accordance with Section XII.B of Attachment “A” of this permit. [A.A.C. R18-2-306.A.5.b]

g. Subpart Da Reporting Requir em ents for Sulfur Dioxide [PSD Permit No. M170843S1-98, Atta chment "B", Condition XV.B.6]

The Permittee shall include in the quarterly reports required under Condition III.E.4.d above, the following additional information in regard
to sulfur dioxide:

i. For sulfur dioxide, the following information shall be reported to the Director for each 24-hour period: [40 CFR 60.51Da(b)]TV Renewal Permit No. 53399 Page 39 of 109 May 31, 2012 APS-Cholla Generating Station (1) Calendar date;

(2) Average sulfur dioxide emission rates (ng/J or lb/million Btu) for each 30 successive boiler operating days, ending with the last 30-day period in the quarter; reasons for non-compliance with the emission standards; and description of corrective actions taken.

(3) Percent reduction of the potential combustion
concentration of sulfur dioxide for each 30 successive boiler operating days, ending with the last 30-day period in the quarter; reasons for non-compliance with the emission standards; and description of corrective actions
taken.

(4) Identification of the boiler operating days for which pollutant or diluents’ data have not been obtained b y an approved method for at least 18 hours of operation of the facility; justification for not obtaining sufficient data; and description of corrective actions taken.

(5) Identification of the time when emissions data have been
excluded from the calculation of average emission rates because of startup, shutdown, emergency conditions, or other reasons, and justification for excluding data for reasons other than startup, shutdown, or emergency
conditions.

(6) Identification of “F” factor used for calculations, method
of determ ination, and type of fuel combusted.

(7) Identification of times when hourly averages have been
obtained based on m anual sampling methods.

(8) Identification of the times when the pollutant
concentration exceeded full span of the continuous

m onitoring system.

(9) Description of any modifications to the continuous

m onitoring system which could affect the ability of the continuous monitoring system to comply with Performance Specification 2 or 3.

ii. For the purpose of SO 2 emission reporting, minimum quantity of
SO 2 emission data requires that the available data from CEMS for each boiler operating day be at least 18 hours in at least 22 out of 30 successive boiler operating days. If the minimum quantity of emissions data is not obtained for any 30 successive boiler operating days, the following information shall be reported to the Director for that 30-day period: [40 CFR 60.49Da(f) and 51Da(c)]

(1) The number of hourly averages available for the outlet

e mission rates (n

o ) and the inlet emission rates (n i ) as applicable.TV Renewal Permit No. 53399 Page 40 of 109 May 31, 2012 APS-Cholla Generating Station (2) The standard deviation of hourly averages for the outlet

e mission rates (s

o ) and inlet emission rates (s i ) as applicable.

(3) The lower confidence limit for the mean outlet emission rate (Eo*) an d the upper confidence limit for the mean inlet emission rate (Ei*) as applicable.

(4) The applicable potential combustion concentration.

(5) The ratio of the upper confidence limit for the mean
outlet em ission rate (Eo*) and the allowable emission rate (E std ) as applicable.

iii. If the sulfur dioxide standards under Condition III.E.1.a and b of
this attach ment are exceeded during emergency conditions because of control system malfunction, the Permittee shall submit a signed statement: [40 CFR 60.51Da(d)]

(1) Indicating if emergency conditions existed and requirem ents under Condition III.C.4 (Emergency Procedures) of this Attachment were met during each period, and

(2) Listing the following information:

(a) Time periods the emergency condition existed;

(b) Electrical output and demand on the owner or operator' s electric utility system and the affected facility;

(c) Amount of power purchased from interconnected neigh boring utility companies during the emergency period;

(d) Percent reduction in emissions achieved;

(e) Atmospheric emission rate (ng/J) of the pollutant discharged; and

(f) Actions taken to correct control system
malfunction.

iv. If fuel pretreatment credit to ward the sulfur dioxide em ission standard is claimed, the Permittee shall submit a signed

statement: [40 CFR 60.51Da(e)]

(1) Indicating what percentage cleaning credit was taken for
the calendar quarter, and whether the credit was determined in accordance with the provisions of III.E.5 of this attachment and Method 19 (appendix A); andTV Renewal Permit No. 53399 Page 41 of 109 May 31, 2012 APS-Cholla Generating Station (2) Listing the quantity, heat content, and date each pretreated fuel shipment was received during the previous quarter; the name and location of the fuel pretreatment facility; and the total quantity and total heat content of all fuels received at the affected facility during the previous quarter.

v. For any periods for which sulfur dioxide emissions data are not available, the Per mittee shall submit a signed statement indicating if any changes were made in operation of the emission control system during the period of data unavailability. Operations of the control system and affected facility during periods of data unavailability are to be compared with operation of the control system and affected facility before and following the period of data unavailability. [40 CFR 60.51Da(f)]

vi. The Permittee shall submit a signed statement indicating
whether: [40 CFR 60.51Da(h)]

(1) The required sulfur dioxide continuous monitoring

sy stem calibration, span, and drift checks or other periodic audits have or ha ve not been performed as specified.

(2) The data used to show compliance was or was not
obtained in accordance with approved methods and procedures of this section a nd is representative of plant performance.

(3) The minimum data requirements have or have not been met; or, the minim um data requirements have not been
met for errors that were unavoidable.

(4) Compliance with the standards has or has not been achieved during the reporting period.

5. Compliance Demonstration Requirements

Compliance determination procedures and methods

a. The Permittee shall determine compliance with the SO 2 standards specified in Conditions III.E.1.a and b of this Attachment as follows:

i. The percent of potential SO 2 emissions (%Ps) to the atmosphere shall be computed using the following equation: [40 CFR 60.50Da(c)(1)]

%Ps=[(100 - %Rf) (100 - %Rg)]/100

where:

%Ps=percent of potential SO 2 emissions, percent

%Rf=percent reduction from fuel pretreatment, percent

%Rg=percent reduction by SO 2 control system, percentTV Renewal Permit No. 53399 Page 42 of 109 May 31, 2012 APS-Cholla Generating Station ii. The procedures in EPA Reference Method 19 may be used to
deter mine percent reduction (%Rf) of sulfur by such processes as fuel pretreatment (physical coal cleaning, hydro desulphurization of fuel oil, etc.), coal pulverizers, and bottom and fly ash
interactions. This determ ination is optional. [40 CFR 60.50Da(c)(2)]

iii. The procedures in EPA Refere nce Method 19 shall be used to determine the percent SO 2 reduction (%Rg) of any SO 2 control
system. [40 CFR 60.50Da(c)(3)]

iv. The appropriate procedures in EPA Reference Method 19 shall
be used to determine the emission rate. [40 CFR 60.50Da(c)(4)]

v. The continuous monitoring system required in Condition III.E.3.
of this Attachment shall be used to determine the concentrations
of SO 2 and O 2 /CO 2

. [40 CFR 60.50Da(c)(5)]

b. Compliance with the sulfur dioxide emission lim itations and percentage reduction requirements under Conditions III.E.1.a and b of this Attachment shall be based on the average emission rate for 30 successive boiler operating days. A separate performance test shall be completed at the end of each boiler operating day, and a new 30 day average emission
rate for sulfur dioxide and a new percent reduction for sulfur dioxide shall be calculated to show compliance with the standards. [40 CFR 60.48Da(e)]

c. Compliance shall be determined by calculating the a rithmetic average of all hourly emission rates for SO 2 for the 30 successive boiler operating days, except for data obtained during startup, shutdown, or the emergency conditions defined in 40 CFR 60.41a. Compliance with the percentage reduction requirement for SO 2 shall be determined based on the average inlet and average outlet SO 2 emission rates for the 30 successive boiler operating days. [40 CFR 60.48Da(g)]

d. The Permittee shall obtain SO 2 emission data for at least 18 hours in at least 22 out of 30 successive boiler operating days. If the Permittee has not obtained the minimum quantity, compliance of Steam Boiler Unit 2
with the SO 2 emission requirements under Conditions III.E.1.a and b of this attachment for the day on which the 30 day period ends may be determined by the Director by following the applicable procedures in
section 7 of EPA Reference Method 19. [40 CFR 60.48Da(h)]

6. Permit Shield

Co mpliance with the terms of this Sec tion shall be deemed compliance of the affected sources subject to this Section with the applicable requirements prescribed under PSD Permit No.M170843S1-98 for SO 2

. [A.A.C. R18-2-325]

F. Nitrogen Oxide Standard

1. Emission Limitations/Standards

a. CoalThe Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 2 any gases which contain nitrogen oxides, expressed as NO 2 in excess of 300 nanogram per joule heat input (0.70 lb per million Btu) derived from solid fossil fuel. [40 CFR 60.44(a) and 44(a)(3)] b. Combination Fuels

The Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 2, wh en different fossil fuels are burned simultaneously in any combination, any gases which contain nitrogen oxides in excess of the applicable standard (in ng/J) derived using the following proration formula: [40 CFR 60.44(b)]



### zyxw z(300) y(130) x(86) w(260) PS NOx 

###    



Where:
PS NOx = prorated standard for nitrogen oxides when burning different fuels simultaneously, in nanograms per joule heat input derived
from all fossil fuels fired or from all fossil fuels and wood residue fired; w = percentage of total heat input derived from lignite;

x = percentage of total heat input derived from gaseous fossil fuel;

y = percentage of total heat input derived from liquid fossil fuel;

and

z = percentage of total heat input derived from solid fossil fuel (except lignite).

2. Air Quality Control Requirements

At all times including periods of startup, shutdown and malfunction, to the extent practicable, the Permittee shall operate and maintain Steam Boiler Unit 2 and
associated low NO

x burners in a manner consistent with good air pollution control practice for minimizing nitrogen oxides emissions . The Permittee shall inspect and maintain the low-NO

x burners in accordance with manufacturer specifications. [A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

3. Monitoring Requirements

a. The Permittee shall calibrate , maintain

, and operate a CEMS for measuring the nitrogen oxides emissions. [40 CFR 60.45(a), A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

b. The continuous emission monitoring systems for NO

x , shall meet the following requirements:

i. 40 CFR Part 75, Appendix A, “Specification and Test
Procedures” [40 CFR 60.13]

(1) Installation and measurement location

TV Renewal Permit No. 53399 Page 43 of 109 May 31, 2012 APS-Cholla Generating StationTV Renewal Permit No. 53399 Page 44 of 109 May 31, 2012 APS-Cholla Generating Station (2) Equipment specifications

(3) Performance specifications

(4) Data acquisition and handling systems

(5) Calibration gas

(6) Certifications tests and procedures

(7) Calculations

ii. 40 CFR Part 75, Appendix B, “Quality Assurance and Quality
Control Procedure”

(1) Quality control program

(2) Frequency of testing [40 CFR 60.13]

iii. Data Reduction

The Permittee shall comply with the data reduction requirements of 40 CFR Part 75.10(d)(1). [40 CFR 60.13(h)]

iv. 40 CFR Part 75, Appendix F, “Conversion Procedures”

The Perm ittee shall convert all hourly pollutant and diluent data to the applicable emissions standard utilizing the procedures of 40 CFR Part 75, Appendix F. [40 CFR 60.45(a), A.A.C. R18-2-306.A.3.a]

4. Recordkeeping and Reporting Requirements

a. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monitoring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other information required by this section recorded in a permanent form suitable for inspection. The file shall be retained for at least five years following the date of such measurements, maintenance, reports and records. [40 CFR 60.7(f)]

b. The Permittee shall comply with all t he recordkeeping and reporting requirements specified in 40 CFR Part 75 Subparts F and G, respectively.
[40 CFR 60.7]

c. The Permittee shall record in a perm anent log for each shutdown, the date and time Steam Boiler Unit 2 intends to begin dropping load to go off line. The log shall be retained fo r at least five (5) years following the
date of each shutdown. [A.A.C. R18-2-306.A.4]

d. Quarterly excess emissions and monitoring system performance reports

i. The Permittee shall submit an excess emissions and monitoring systems performance (MSP) report and/or a summary report form to the Department for every calendar quarter, unless the
total duration of excess emissions for the reporting period is lessTV Renewal Permit No. 53399 Page 45 of 109 May 31, 2012 APS-Cholla Generating Station than 1 percent of the total operating time for the reporting period and the continuous monitoring system downtime for the reporting period is less than 5 per cent of the total operating time for the reporting period, in which case only the summary report
form shall be submitted and the excess emissions report need not be submitted unless requested by the Department. All quarterly reports shall be postmarked by th e 30th day following the end of each calendar quarter. [40 CFR 60.7(c) and (d), 45(g), 51Da(j) and 51Da(k)]

ii. The summary report form submission required in the preceding
Condition III .F.3.b.i shall be in the format specified in 40 CFR 60.7(d). Each excess emission and MSP report shall include the following information: [40 CFR 60.7(c)]

(1) The magnitude of excess emissions computed, any
conversion f actor(s) used, and the date and time of commencement and completion of each time period of excess emissions. The process operating time during the reporting period.

(2) Specific identification of each period of excess

e missions that occurs duri ng startups, shutdowns, and
malfunctions of the steam boiler unit. The nature and cause of any malfunction (if known), the corrective action taken or preventative measures adopted.

(3) The date and time identifying each period during which
the contin uous monitoring system was inoperative except for zero and span checks and the nature of the system repairs or adjustments.

(4) When no excess emissions have occurred or the
continuo us monitoring system(s) have not been inoperative, repaired, or adjusted, such information shall be stated in the report.

e. Excess Emissions Definitions

NO

x excess emissions for Steam Boiler Unit 2 are defined as any threehour period during which the average NO

x emissions (arithmetic average of three contiguous one-hour periods), as measured by a continuous emissions monitoring system, exceed the applicable standards specified
in Condition III.F.1 of this Attachment. [40 CFR 60.45(g)(3)]

f. Emission deviations reporting requirements

In addition t o the quarterly reporting required under Condition III.F.4.d above, the Permittee shall report em issions exceeding an emission
limitation or standard as deviations in accordance with Section XII.B of Attachment “A” of this permit. [A.A.C. R18-2-306.A.5.b]

5. Performance Testing Requirements

The Perm ittee shall perform annual perfo rmance tests for nitrogen oxidesTV Renewal Permit No. 53399 Page 46 of 109 May 31, 2012 APS-Cholla Generating Station emissions from the stack of Steam Boile r Unit 2, using the following reference methods and procedures: [40 CFR 60.8(a)]

a. Reference Method

EPA Reference Method 7 shall be used to determine the nitrogen oxides concentration (C) at the stack of Steam Boiler Unit 2. [40 CFR 60.46(b)(5)]

b. Emission Rate

For the purpose of co mpliance determination, the emission rate (E) of
PM or NO

x shall be computed for each run using the following equation: [40 CFR 60.46(d)(1)]

E = C Fd (20.9)/(20.9 - %O 2 )
Or

E = C F

c (100/%CO 2 )

E = emission rate of pollutant, ng/J (1b/million Btu).

C = concentration of pollutant, ng/dscm (1b/dscf).

%O 2 = oxygen concentration, percent dry basis.

%CO 2 = carbon monoxide concentration, percent dry basis.

Fd = factor as determined from Method 19

F
c = factor as determined in a ppropriate sections of Method 19.

c. The Permittee may conduct the annual performance tests using alternatives described in 40 CFR 60.46(d).

6. Permit Shield

Co mpliance with the terms of this Sec tion shall be deemed compliance of the affected source subject to this Section with the applicable requirements prescribed under 40 CFR 60.44, 40 CFR 60.44, 40 CFR 60.44, and 40 CFR

60.45. [A.A.C. R18-2-325]

G. Carbon Monoxide

1. Emission Limitations/Standards



### a. At all times, excluding periods of startup and shutdown, the Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 2, any gases which contain carbon monoxide in excess
of:

i 0.15 lb per million Btu heat input derived from combustion of fuel, based on a 30-day rolling average. [A.A.C. R18-2-406.A.4]

ii. 0.75 lb per million Btu heat input derived from combustion of fuel, on an hourly basis. [A.A.C. R18-2-406.A.5]

b. During periods of startup and shutdown, the Permittee shall not cause to be discharged into the atmosphere fro m the stack of Steam Boiler Unit 2,TV Renewal Permit No. 53399 Page 47 of 109 May 31, 2012 APS-Cholla Generating Station any gases which contain carbon monoxide in excess of 350 pounds per
hour. [A.A.C. R18-2-406.A.5]

2. Air Quality Control Requirements [A.A.C. R18-2-406.A.4]

a. At all times, including periods of startup, shutdown and malfunction, to the extent practicable, the Permittee shall operate and maintain Steam
Boiler Unit 2 and associated low NO

x burners in a manner consistent with good combustion practices fo r minimizing carbon monoxide

emissions. A.A.C. R18-2-306.A.3.a, 331.A.3.c and 406.A.4] [Material Permit Condition identified by underline and italics]

b. For the purpose of this Section, the good combustion practices shall include, but is not limited to, the following components:

i. Good air/fuel mixing in the combustion zone;

ii. High temperatures and low oxygen levels in the primary

co mbustion zone;

iii. Overall excess oxygen levels high enough to complete

co mbustion while maximizing boiler thermal efficiency; and

iv. Sufficient residence time to complete combustion.

c. Determination of whether the good combustion practices are being implemented for minimizing boiler carbon monoxide emissions will be
based on information available to th e Director which may include, but not limited to, monitoring results, re view of operation and maintenance procedures and records, and inspection of the source.

3. Monitoring, Recordkeeping and Reporting Requirements

a. The Permittee shall install, calibrate , maintain, and operate CEMS at each affected steam boiler unit , and record the output of the system, for measuring carbon monoxide (CO) and diluents (O 2 /CO 2 ) emissions from exhaust of the boiler’s stack . The output of the CEMS shall be expressed in pounds CO per million Btu heat input.
[ A.A.C. R18-2-306.A.3.a, 331.A.3.c and 406.A.4] [Material Permit Condition identified by underline and italics]

b. The existing diluents (O 2 /CO 2 ) continuous monitoring systems required under Sections III.E of Attachment “B” of the permit may be used to satisfy the requirement for monitoring of diluents emissions.

c. All continuous monitoring systems shall meet the following requirem ents: [A.A.C. R18-2-306.A.3.a and 406.A.4]

i. 40 CFR Part 75, Appendix A "Specification and Test
Procedures" for installation of the NO

x monitor shall be used for CO monitor by substituting NO

x for CO. Due to normal combustion variability, a dual range CO monitor shall be installed. The RATA specification shall be measured with 2 decimal places in lb CO per million BTU.

ii. 40 CFR Part 75, Appendix A, “Specification and TestTV Renewal Permit No. 53399 Page 48 of 109 May 31, 2012 APS-Cholla Generating Station Procedures” for CO and O 2 /CO 2 monitors

(1) Installation and measurement location

(2) Equipment specifications

(3) Performance specifications

(4) Data acquisition and handling systems

(5) Calibration gas

(6) Certifications tests and procedures

(7) Calculations

iii. 40 CFR Part 75, Appendix B, “Quality Assurance and Quality
Control Proce dure”

(1) Quality assurance/quality control program

(2) Frequency of testing

iv. 40 CFR Part 60 Appendix “F”, Quality Assurance Procedure for CO monitor for determining with pounds per hour emission rate
under Condition III.G.1.b of this Attachment.

v. Data Reduction

The Permittee shall comply with the data reduction requirements of 40 CFR Part 75.10(d)(1).

vi. Missing Data Substitution

(1) The Permittee shall, in processing any CO emission data gaps throu ghout operation, comply with the appropriate provisions in 40 CFR Part 75, Subpart D, “Missing Data
Substitution Procedures” and Appendix C, “Missing Data Estimation Procedures”. For the purpose of this Section, when monitor data availability reaches below 80%, all CO emission data ga ps shall be substituted using a CO emission rate not less than 0.75 lb per million Btu heat input derived from combustion of fuel.

(2) The Permittee may elect to supplement CO emission data
with the fo llowing USEPA reference methods and procedures:

(a) Reference Method 10 shall be used to determine
the CO conce ntration at the same location as the
CO monitor.

(b) The emission rate correction factor, integrated bag sam pling and analysis procedure of
Reference Method 3B shall be used to determine
the O 2 /CO 2 concentration at the same location as
the O 2 /CO 2 monitor.

(c) The procedures in Reference Method 19 shall be
used to com pute each 1-hour averageTV Renewal Permit No. 53399 Page 49 of 109 May 31, 2012 APS-Cholla Generating Station concentration in ng/J (pounds per million Btu).

(d) As Method 19 does not provide conversion
factors for carbon m onoxide, a conversion factor
of 7.269×10 -8 shall be used to convert parts per million (ppm) to pounds per standard cubic foot (lb/scf).

vii. 40 CFR Part 75, Appendix F, “Conversion Procedures”

The Perm ittee shall convert all hour ly pollutant and diluent data to the applicable emissions sta ndard utilizing the procedures of 40 CFR Part 75, Appendix F.

d. Except for system breakdowns, repair s, calibration checks, and zero and span adjustments, each continuous m onitoring system prescribed in this Section shall complete a minimum of one cycle of operation (sampling, analyzing, and data recording) for each successive 15-minute period. [A.A.C. R18-2-306.A.3.a and 406.A.4]

e. CO Emissions Compliance Determination [A.A.C. R18-2-406.A.4 and 5]

i. The Permittee shall use CO emission data measured and recorded by the continuous m onitoring systems prescribed in this Section to demonstrate compliance with the carbon
monoxide emission standards set forth in Condition III.G.1 of
this Attachment.

ii. Compliance with Condition III.G.1.a.i of this Attachment shall be based on the average e mission rate for 30 successive calendar days. A new 30-day average carbon monoxide emission rate shall be determined at the end of each calendar day by calculating the arithmetic average of all hourly carbon monoxide emission rates for the past 30 successive calendar days, except for data obtained during periods of startup, shutdown, or
malfunction.

iii. The following shall be consid ered periods of excess emissions:

(1) Any calendar day for which the 30-day rolling average
CO emissio n rate, excluding periods of startup, shutdown, or malfunction, as determined by the applicable continuous monitoring systems in accordance with Condition III.G.3.e.ii above exceeds the 30-day average CO emission limit set forth in Condition
III.G.1.a.i of this Attachment.

(2) Any hour for which the hourly CO emission rate, excluding periods of startup, shutdown or malfunction, as measured by the applicable continuous monitoring systems of this Section exceeds the hourly CO emission
limit set forth in Condition III.G.1.a.ii of this
Attachment.

(3) Any periods of startup, shutdown or malfunction, for which the CO emissions rate for any unit exceeds theTV Renewal Permit No. 53399 Page 50 of 109 May 31, 2012 APS-Cholla Generating Station emission limit set forth in Condition III.G.1.b of this
Attachment.

iv. All excess emissions shall be reported in accordance with Section XII, Attach ment “A” of the permit. [A.A.C. R18-2-306.A.5.b and 310.01]

f. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monito ring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other in formation required by this part recorded in a permanent form suitable for inspection. The file shall be retained for at least five years follo wing the date of such measurements, maintenance, reports, and records. [A.A.C. R18-2-306.A.4.a and 406.A.4] IV. STEAM BOILER UNIT 3

A. Applicability

This section applies to Unit 3 boiler as d escribed in Attachment “C” of this permit.

B. Fuel Limitation [Installation Permit No. 1037]

The Permittee shall burn only the foll owing fuels in Steam Boiler Unit 3:

1. Coal.

2. No. 2 fuel oil for startup and stabilization.

C. Operation Procedures

1. Startup

During startups of Steam Boiler Unit 3, the fabric filter shall be placed in service before startup of any boiler forced dr aft or induced draft fan. The fabric filter may be removed from service just pr ior to igniting oil fires (startup fuel) but must be returned to service before coal fires are placed in the boiler. The FGD system shall be placed in service aft er the fabric filter is placed in service, and before coal fires are in the boiler

. [40 CFR 60.11(d) and A.A.C. R18-2-331.A.3.e] [Material Permit Condi tion identified by underline and italics ] b. Shutdown

During shutdowns of Steam Boiler Unit 3 the fabric filter shall remain in servi ce until after the boiler forced draft fans and induced draft fans have been turned off. The FGD system shall remain in se rvice until coal fires in the boiler are out

. [40 CFR 60.11(d) and A.A.C. R18-2-331.A.3.e] [Material Permit Condi tion identified by underline and italics] c. Malfunction

For Steam Boiler Unit 3 with any malfunction of its fabric filter that exceeds four hours, if fires are in the boiler, the Permittee shall reduce the unit’s load so that the fabric filter compartments in service can properly process and treat theTV Renewal Permit No. 53399 Page 51 of 109 May 31, 2012 APS-Cholla Generating Station volume of flue gas being produced. If a malfunction makes it impossible to properly process and treat the volume of fl ue gas being produced, the unit shall
be shut down. [40 CFR 60.11(d)]

D. Particulate Matter & Opacity

1. Emission Limits/Standards

a. Opacity

The opacity of emissions from the st ack of Steam Boiler Unit 3 shall not be greater than 20 percent at all times except for periods of startup, shutdown, and malfunction as defined in Conditions I.A.1, 2 and 3 of this Attachment, and for one six-minute period per hour of not more than 27 percent opacity. Opacity readings of portions of plumes which contain condensed, uncombined water vapor shall not be used for purposes of determining compliance with the opacity standard

. [40 CFR 60.42(a)(2), 60.11(c), 60.11( e)(1) and A.A.C. R18-2-331.A.3.a] [Material Permit Condition identified by underline and italics ]

b. Particulate Matter

The Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 3, any gases which contain particulate matter in excess of 43 nanogram per joule heat input (0.10 lb per million Btu) derived from fossil fuel. [40 CFR 60.42(a)(1)]

2. Air Pollution Control Requirements

At all times, including periods of startup, shutdown, and malfunction, the Permittee shall, to the extent practicable, operate and maintain Steam Boiler
Unit 3 and the fabric filter control device in a manner consistent with good air pollution control practice for minimizing particulate matter emissions . The Permittee shall inspect and maintain the fa bric filter control device in accordance with manufacturer specifications. [40 CFR 60.11(d) and A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

3. Continuous Monitoring

a. The Permittee shall calibrate , maintain, and operate COMS at the fabric filter outlet for measuring the opacity of emissions

. [40 CFR 60.45(a), A.A.C. R18-2-331.A.3.c] [Material Permit Condi tion identified by underline and italics]

b. The continuous opacity monitori ng sy stem shall meet the following requirements:

i. 40 CFR 60, Appendix B, Performance Specification 1, “Specificatio n and Test Procedures for Opacity Continuous Emission Monitoring Systems in Stationary Sources”
[40 CFR 60.13] (1) Apparatus

(2) Installation Specifications

(3) Design and Performance Specifications

(4) Design Specifications Verification ProcedureTV Renewal Permit No. 53399 Page 52 of 109 May 31, 2012 APS-Cholla Generating Station (5) Performance Specifications Verification Procedure

(6) Equations

ii. Quality assurance requirements:

(1) Calibration Checks

The Perm ittee shall check the zero (or low-level value between 0 and 20% of span value) and span calibration drifts at least once daily in accordance with a written procedure. [40 CFR 60.13(d)(1)]

(2) Zero and Span Drift Adjustments

(a) The zero and span shall, as a minimum, be adjusted whenever the 24-hr zero drift or 24-hr span drift exceeds 4% opacity. [40 CFR 60.13(d)(1)]

(b) The system shall allow for the amount of excess zero and span drift measured at the 24-hour interval checks to be recorded and quantified. [40 CFR 60.13(d)(1)]

(c) The optical surfaces exposed to the effluent

gases shall be cleaned prior to performing the zero and span drift adjustments, except for systems using automatic zero adjustments. [40 CFR 60.13(d)(1)]

(d) For systems using automatic zero adjustments, the optical s urfaces shall be cleaned when the cumulative automatic zero compensation exceeds 4% opacity. [40 CFR 60.13(d)(1)]

(3) System Checks

A method for producing a simulated zero opacity condition and an upscale (span) opacity condition using a certified neutral density filte r or other related technique to produce a known obscuration of the light beam to provide a system check of the analyzer internal optical surfaces and all electronic circuitry including the lamp and photo detector assembly shall be used by the
Permittee. [40 CFR 60.13(d)(2)]

(4) Minimum Frequency of Operation

Except during periods of system breakdowns, repairs, calibration checks, and zero and span adjustments, the COMS shall be in continuous operation and shall complete a minimum of one cycle of sampling and analyzing for each successive 10-second period and one cycle of data recording for each successive 6-minute period. [40 CFR 60.13(e)(1)]TV Renewal Permit No. 53399 Page 53 of 109 May 31, 2012 APS-Cholla Generating Station (5) Data Reduction Procedures [40 CFR 60.13(h)]

(a) The Permittee shall reduce all data from the
COMS to 6-m inute averages. Six-minute opacity averages shall be calculated from 36 or more data points equally spaced over each 6- minute period.

(b) Data recorded during periods of system breakdowns, repairs, calibration che cks, and zero and span adjustments shall not be included in the data averages computed under the previous Condition. An arithmetic or integrated average of all data may be used.

4. Recordkeeping and Reporting Requirements

a. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monitoring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other information required by this section recorded in a permanent form suitable for inspection. The file shall be retained for at least five years following the date of such measurements, maintenance, reports and records. [40 CFR 60.7(f)]

b. The Permittee shall comply with all t he recordkeeping and reporting requirements of 40 CFR Part 75 Subparts F and G, respectively.
[40 CFR 60.7] c. The Permittee shall record in a permanent log for each shutdown, the date and time Steam Boiler Unit 3 intends to begin dropping load to go off line. The log shall be retained fo r at least five (5) years following the
date of each shutdown. [A.A.C. R18-2-306.A.4]

d. Quarterly excess emissions and monitoring system performance reports

i. The Permittee shall submit an excess emissions and monitoring systems performance (MSP) report and/or a summary report form to the Department for every calendar quarter, unless the
total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting period and the continuous monitoring system downtime for the reporting period is less than 5 per cent of the total operating time for the reporting period, in which case only the summary report
form shall be submitted and the excess emissions report need not be submitted unless requested by the Department. All quarterly reports shall be postmarked by th e 30th day following the end of each calendar quarter. [40 CFR 60.7(c) and (d), 45(g), 51Da(j) and 51Da(k)]

ii. The summary report form submission required in the preceding
Condition IV.D.4.d.i shall be in the format specified in 40 CFR 60.7(d). Each excess emission and MSP report shall include the following information: [40 CFR 60.7(c)]TV Renewal Permit No. 53399 Page 54 of 109 May 31, 2012 APS-Cholla Generating Station (1) The magnitude of excess emissions computed, any
conversion f actor(s) used, and the date and time of commencement and completion of each time period of excess emissions. The process operating time during the reporting period.

(2) Specific identification of each period of excess

e missions that occurs duri ng startups, shutdowns, and
malfunctions of the steam boiler unit. The nature and cause of any malfunction (if known), the corrective action taken or preventative measures adopted.

(3) The date and time identifying each period during which
the contin uous monitoring system was inoperative except for zero and span checks and the nature of the system repairs or adjustments.

(4) When no excess emissions have occurred or the
continuo us monitoring system(s) have not been inoperative, repaired, or adjusted, such information shall be stated in the report.

iii. Definitions

Periods of excess emissions and monitoring systems (MS) downtime that shall be reported are defined as follows:

Opacity excess emissions are defined as any six-minute period during which the average opacity of emissions from Steam Boiler Unit 3 fabric filter outlet exceeds 20 percent opacity as measured by a continuous opacity monito r, except that one six-minute average per hour of up to 27 percent opacity need not be reported. [ 40 CFR 60.45(g)(1)] iv. Emission deviations reporting requirements

In addition to the quarterly reporting required under Condition
IV.D.4.d above, the Permittee shall report emissions exceeding
an emission limitation or standard as deviations in accordance with Section XII.B of Attachment “A” of this permit. [A.A.C. R18-2-306.A.5.b] 5. Performance Testing Requirements

a. The Permittee shall perform an annua l opacity observation of the stack of
Steam Boiler Unit 3 in accordance with EPA Reference Method 9. [40 CFR 60.8(a) and 46(b)(3)]

b. The Permittee shall perform annual pe rformance tests for emissions of particulate matter from the stack of Steam Boiler Unit 3, using the following reference methods and procedures: [40 CFR 60.8(a)]

i. Reference Method

EPA Reference Method 5 or 5B shall be used to determine the particulate matter concentration (C) at the stack of Steam Boiler
Unit 3. [40 CFR 60.46(b)(2)]TV Renewal Permit No. 53399 Page 55 of 109 May 31, 2012 APS-Cholla Generating Station ii. Emission Rate

For the purpose of compliance determination, the emission rate (E) of PM shall be computed for each run using the following equation: [40 CFR 60.46(d)(1)]

E = C F d (20.9)/(20.9 - %O 2 )

Or

E = C F

c (100/%CO 2 )

E = emission rate of pollutant, ng/J (1b/million Btu).

C = concentration of pollutant, ng/dscm (1b/dscf).

%O 2 = oxygen concentration, percent dry basis.

%CO 2 = carbon monoxide concentration, percent dry basis.

Fd = factor as determined from Method 19

F
c = factor as determined in a ppropriate sections of Method 19.

iii. The Permittee may conduct the annual performance tests using alternatives described in 40 CFR 60.46(d).

c. Used Oil and Used Oil Fuel Testing

The Permittee shall perform a semian nual sample test for the used oil and/or used oil fuel to be burned for flash point and concentrations (ppm) of Arsenic, Cadmium, Chromium, Lead, and PCBs, using the analytical methods specified in EPA Publica tion SW-846, Third Edition (document number 955-001-00000-1). All sample tests shall be conducted in the laboratories certified by the Arizona Department of Health Services.
[A.R.S. §49-426.G.2] 6. Compliance Assurance Monito ring for Particulate Matter

The Permittee shall conduct the complia nce assur ance monitoring required in Attachment “E” of this permit for Steam Boiler Unit 3. [40 CFR Part 64]

7. Permit Shield

Co mpliance with the terms of this Secti on shall be deemed compliance with the applicable requirements prescribed under 40 CFR 60.42, 40 CFR 60.42, 40 CFR 60.45, 40 CFR 60.45, 40 CFR 60.46 for the affected source subject to this
Section. A.A.C. R18-2-325]

E. Sulfur Dioxide

1. Emission Standards/Limitations

The Permittee shall not cause to be discha rged into the atmosphere from the stack of Steam Boiler Unit 3 any gases which c ontain sulfur dioxide in excess of 340 nanogram per joule heat input (0.8 po unds per million Btu) derived from both solid and liquid fossil fuel.
[A.A.C. R18-2-903.1, A.A.C. R 18-2-903.4, 40 CFR 60.43(a)(1)]TV Renewal Permit No. 53399 Page 56 of 109 May 31, 2012 APS-Cholla Generating Station 2. Control Requirements

The Permittee shall operate and maintain at all times

, including periods of startup, shutdown and malfunction, to the extent practicable , Steam Boiler Unit
3 and the lime slurry FGD system in a manner consistent with good air pollution control practice for minimizing sulfur dioxide emissions . The Permittee shall inspect and maintain the FGD control device in accordance with manufacturer specifications. [40 CFR 60.11(d) and A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

3. Continuous Monitoring SO 2 Emissions, and O 2 /CO 2 Content [PSD Permit No. M170843S1-98, Atta chment “B”, Condition XV.A]

a. The Permittee shall calibrate , maintain, and operate a CEMS, and record the output of the system, for measuring sulfur dioxide emissions from the stack of Steam Boiler Unit 3. [40 CFR 60.49 Da(b), A.A.C. R18-2-331.A.3.c] [Material Permit Condition identified by underline and italics]

b. The Permittee shall calibrate , maintain, and operate a continuous monitoring system, and record the output of the system, for measuring
the O 2 /CO 2 content of the flue gases at the location where SO 2 emissions
are monitored. [40 CFR 60.49Da(d), A.A.C. R18-2-331.A.3.c] [Material Permit Condi tion identified by underline and italics]

c. The Permittee shall operate the SO 2 and O 2 /CO 2 continuous monitoring systems and record data during all periods of operation of Steam Boiler Unit 3 including periods of startup, shutdown, malfunction, or emergency conditions, except for continuous mon itoring system breakdown, repairs, calibration checks, and zero and span adjustments. [40 CFR 60.49 Da(e)]

d. The continuous emission monitoring systems for SO 2 , and O 2 /CO 2 shall meet the following requirements:

i. 40 CFR Part 75, Appendix A, “Specification and Test
Procedures”
[40 CFR 60.13] (1) Installation and measurement location

(2) Equipment specifications

(3) Performance specifications

(4) Data acquisition and handling systems

(5) Calibration gas

(6) Certifications tests and procedures

(7) Calculations

ii. 40 CFR Part 75, Appendix B, “Quality Assurance and Quality
Control Procedure” [40 CFR 60.13]

(1) Quality control program

(2) Frequency of testingTV Renewal Permit No. 53399 Page 57 of 109 May 31, 2012 APS-Cholla Generating Station iii. Data Reduction

The Permittee shall comply with the data reduction requirements of 40 CFR Part 75.10(d)(1). [40 CFR 60.13]

iv. 40 CFR Part 75, Appendix F, “Conversion Procedures”

The Permittee shall convert all hourly pollutant and diluent data to the applicable emissions standard utilizing the procedures of 40 CFR Part 75, Appendix F. [A.A.C. R18-2-306.A.3.a ]

e. Sulfur Dioxide Emissions Missing Data Supplemental Procedures

In addition to the requirements specified in the preceding Condition IV.E.3.d of this Attachment, the Permittee shall obtain the SO 2 emission
data for at least 18 hours in at least 22 out of 30 successive boiler operating days. If this minimum data requirement cannot be met with the continuous monitoring system in use, the Permittee shall supplement
SO 2 emission data with other monitoring systems approved by the Director or the following reference methods and procedures: [40 CFR 60.49Da(f), (h) and (j) and PSD Permit No. M170843S1-98, Attachment “B”, Condition XV.A]

i. Reference Method 6 shall be used to determine the SO 2 concentration at the same location as the SO 2 monitor.

ii. The emission rate correction factor, integrated bag sampling and analy sis procedure of Reference Method 3B shall be used to
determine the O 2 /CO 2 concentration at the same location as the
O 2 /CO 2 monitor.

iii. The procedures in Reference Method 19 shall be used to

co mpute each 1-hour average concentration in ng/J (pounds per million Btu).

iv. As alternatives, the referen ce methods and procedures described in 40 CFR 49Da(j) may be used.

4. Recordkeeping and Reporting Requirements

a. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monitoring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other information required by this section recorded in a permanent form suitable for inspection. The file shall be retained for at least five years following the date of such measurements, maintenance, reports and records. [40 CFR 60.7(f)]

b. The Permittee shall comply with all t he recordkeeping and reporting requirements of 40 CFR Part 75 Subparts F and G, respectively.
[40 CFR 60.7]

c. The Permittee shall record in a perm anent log for each shutdown, the date and time Steam Boiler Unit 3 intends to begin dropping load to goTV Renewal Permit No. 53399 Page 58 of 109 May 31, 2012 APS-Cholla Generating Station off line. The log shall be retained fo r at least five (5) years following the
date of each shutdown. [A.A.C. R18-2-306.A.4]

d. Quarterly excess emissions and monitoring system performance reports

i. The Permittee shall submit an excess emissions and monitoring systems performance (MSP) report and/or a summary report form to the Department for every calendar quarter, unless the
total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting period and the continuous monitoring system downtime for the reporting period is less than 5 per cent of the total operating time for the reporting period, in which case only the summary report
form shall be submitted and the excess emissions report need not be submitted unless requested by the Department. All quarterly reports shall be postmarked by th e 30th day following the end of each calendar quarter. [40 CFR 60.7(c) and (d), 45(g), 51Da(j) and 51Da(k)]

ii. The summary report form submission required in the preceding
Condition IV.E.4.d.i shall be in the format specified in 40 CFR 60.7(d). Each excess emission and MSP report shall include the following information: [40 CFR 60.7(c)]

(1) The magnitude of excess emissions computed, any
conversion f actor(s) used, and the date and time of commencement and completion of each time period of excess emissions. The process operating time during the reporting period.

(2) Specific identification of each period of excess

e missions that occurs duri ng startups, shutdowns, and
malfunctions of the steam boiler unit. The nature and cause of any malfunction (if known), the corrective action taken or preventative measures adopted.

(3) The date and time identifying each period during which
the contin uous monitoring system was inoperative except for zero and span checks and the nature of the system repairs or adjustments.

(4) When no excess emissions have occurred or the
continuo us monitoring system(s) have not been inoperative, repaired, or adjusted, such information shall be stated in the report.

e. Definitions

Periods of excess emissions and monitoring systems (MS) downtime that shall be reported are defined as follows:

SO 2 excess emissions are defined as any three-hour period during which, the average SO 2 emissions from Steam Boiler Unit 3 stack (arithmetic average of three contiguous one-hour periods) as measured by a continuous monitoring system ex ceed 0.8 pounds per million Btu forboth solid and liquid fossil fuel, as speci fied in Condition IV.E.3 of this
Attachment. [40 CFR 60.45(g)(2)] f Emission deviations reporting requirements

In addition to the quarterly reporting required under Condition IV.C.4.d above, the Permittee shall report emissions exceeding an emission
limitation or standard as deviations in accordance with Section XII.B of Attachment “A” of this permit. [A.A.C. R18-2-306.A.5.b]

5. Compliance Demonstration Requirements

The Perm ittee shall use the continuous monitoring system described in Condition IV.E.3.a of this Attachment to demonstrate compliance with the 0.8 pound per
million Btu sulfur dioxide emission limitations in Condition IV.E.1 of this Attachment on a 3-hour rolling average basis. [A.A.C. R18-2-306.A.3.c]

6. Permit Shield

Co mpliance with the terms of this Secti on shall be deemed compliance with the applicable requirements prescribed under A.A.C. R18-2-903.4, A.A.C.R18-2- 903.1, 40 CFR 60.43(a)(1), 40 CFR 60.49Da, 40 CFR 60.45(g)(2), and PSD Permit No.M170843S1-98 for the affected source subject to this Section.
[A.A.C. R18-2-325] F. Nitrogen Oxides

1. Emission Limits/Standards

a. Coal

The Perm ittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 3 any gases which contain nitrogen oxides, expressed as NO 2 in excess of 300 nanogram per joule heat input (0.70 lb per million Btu) derived from solid fossil fuel. [60 CFR 60.44(a)(3)]

b. Combination Fuels

The Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 3, wh en different fossil fuels are burned simultaneously in any combination, any gases which contain nitrogen oxides in excess of the applicable standard (in ng/J) derived using the following proration formula: [40 CFR 60.44(b)]



### zyxw z(300) y(130) x(86) w(260) PS NOx 

###    



Where:

PS NOx = prorated standard for nitrogen oxides when burning different fuels simultaneously, in nanograms per joule heat input derived
from all fossil fuels fired or from all fossil fuels and wood residue fired;

w = percentage of total heat input derived from lignite;

TV Renewal Permit No. 53399 Page 59 of 109 May 31, 2012 APS-Cholla Generating StationTV Renewal Permit No. 53399 Page 60 of 109 May 31, 2012 APS-Cholla Generating Station x = percentage of total heat i nput derived from gaseous fossil fuel;

y = percentage of total heat i nput derived from liquid fossil fuel; and

z = percentage of total heat input derived from solid fossil fuel (except lignite).

2. Air Quality Control Requirements

At all times including periods of startup, shutdown and malfunction, to the extent practicable, the Permittee shall operate and maintain Steam Boiler Unit 3 and
associated low NO

x burners in a manner consistent with good air pollution control practice for minimizing nitrogen oxides emissions . The Permittee shall inspect and maintain the low NO

x burners in accordance with manufacturer specifications. [A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

3. Monitoring, Recordkeeping and Reporting Requirements

a. The Permittee shall calibrate , maintain, and operate CEMS for measuring nitrogen oxide (NO

x ) emissions from the stack of Steam Boiler
Unit 3. [A.A.C. R18-2-306.A.3.c, A.A.C. R18-2-331.A.3.c] [Material Permit Condi tion identified by underline and italics]

b. The continuous emission monitoring systems for NO

x shall meet the following requirements:

i. 40 CFR Part 75, Appendix A, “Specification and Test
Procedures”
[A.A.C. R18-2-306.A.3.c] (1) Installation and measurement location

(2) Equipment specifications

(3) Performance specifications

(4) Data acquisition and handling systems

(5) Calibration gas

(6) Certifications tests and procedures

(7) Calculations

ii. 40 CFR Part 75, Appendix B, “Quality Assurance and Quality
Control Procedure” [A.A.C. R18-2-306.A.3.c]

(1) Quality control program

(2) Frequency of testing

iii. Data Reduction

The Permittee shall comply with the data reduction requirements of 40 CFR Part 75.10(d)(1). [A.A.C. R18-2-306.A.3.c]

iv. 40 CFR Part 75, Appendix F, “Conversion Procedures”

The Permittee shall convert all hourly pollutant and diluent dataTV Renewal Permit No. 53399 Page 61 of 109 May 31, 2012 APS-Cholla Generating Station to the applicable emissions standard utilizing the procedures of 40 CFR Part 75, Appendix F. [A.A.C. R18-2-306.A.3.c]

4. Recordkeeping and Reporting Requirements

a. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monitoring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other information required by this section recorded in a permanent form suitable for inspection. The file shall be retained for at least five years following the date of such measurements, maintenance, reports and records. [40 CFR 60.7(f)]

b. The Permittee shall comply with all t he recordkeeping and reporting requirements of 40 CFR Part 75 Subparts F and G, respectively.
[40 CFR 60.7]

c. The Permittee shall record in a perm anent log for each shutdown, the date and time Steam Boiler Unit 3 intends to begin dropping load to go off line. The log shall be retained fo r at least five (5) years following the
date of each shutdown. [A.A.C. R18-2-306.A.4]

d. Quarterly excess emissions and monitoring system performance reports

i. The Permittee shall submit an excess emissions and monitoring systems performance (MSP) report and/or a summary report form to the Department for every calendar quarter, unless the
total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting period and the continuous monitoring system downtime for the reporting period is less than 5 per cent of the total operating time for the reporting period, in which case only the summary report
form shall be submitted and the excess emissions report need not be submitted unless requested by the Department. All quarterly reports shall be postmarked by th e 30th day following the end of each calendar quarter. [40 CFR 60.7(c) and (d), 45(g), 51Da(j) and 51Da(k)]

ii. The summary report form submission required in the preceding
Condition IV.F.3.d.i shall be in the format specified in 40 CFR 60.7(d). Each excess emission and MSP report shall include the following information: [40 CFR 60.7(c)]

(1) The magnitude of excess emissions computed, any
conversion f actor(s) used, and the date and time of commencement and completion of each time period of excess emissions. The process operating time during the reporting period.

(2) Specific identification of each period of excess

e missions that occurs duri ng startups, shutdowns, and
malfunctions of the steam boiler unit. The nature andTV Renewal Permit No. 53399 Page 62 of 109 May 31, 2012 APS-Cholla Generating Station cause of any malfunction (if known), the corrective action taken or preventative measures adopted.

(3) The date and time identifying each period during which
the contin uous monitoring system was inoperative except for zero and span checks and the nature of the system repairs or adjustments.

(4) When no excess emissions have occurred or the
continuo us monitoring system(s) have not been inoperative, repaired, or adjusted, such information shall be stated in the report.

iii. Emission deviations reporting requirements

In addition t o the quarterly reporting required under Condition
IV.F.3.d above, the Permittee shall report emissions exceeding
an emission limitation or standard as deviations in accordance with Section XII.B of Attachment “A” of this permit. [A.A.C. R18-2-306.A.5.b] 5. Performance Testing Requirements

The Perm ittee shall perform annual perfor mance tests for emissions of nitrogen oxides from the stack of Steam Boiler Unit 3, using the following reference methods and procedures: [40 CFR 60.8(a)]

a. Nitrogen Oxides

EPA Reference Method 7 shall be used to determine the nitrogen oxides concentration (C) at the stack of Steam Boiler Unit 3. [40 CFR 60.46(b)(5)]

b. Emission Rate

For the purpose of co mpliance determination, the emission rate (E) of
NO

x shall be computed for each r un using the follo wing equation: [40 CFR 60.46(d)(1)]

E = C F d (20.9)/(20.9 - %O 2 )

Or

E = C F

c (100/%CO 2 )

E = emission rate of pollutant, ng/J (1b/million Btu).

C = concentration of pollutant, ng/dscm (1b/dscf).

%O 2 = oxygen concentration, percent dry basis.

%CO 2 = carbon monoxide concentration, percent dry basis.

Fd = factor as determined from Method 19

F
c = factor as determined in a ppropriate sections of Method 19.

c. The Permittee may conduct the annual performance tests using alternatives described in 40 CFR 60.46(d).TV Renewal Permit No. 53399 Page 63 of 109 May 31, 2012 APS-Cholla Generating Station 6. Permit Shield

Co mpliance with the terms of this Section shall be deemed compliance with the applicable requirements prescribed under A.A.C. R18-2-903.4, 40 CFR 60.42, 40 CFR 60.44, 40 CFR 60.44, 40 CFR 60.46, 40 CFR 60.46 for the affected source subject to this Section. [A.A.C. R18-2-325]

G. Carbon Monoxide

1. Emission Limitations/Standards



### a. At all times, excluding periods of startup and shutdown, the Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 3, any gases which contain carbon monoxide in excess
of:

i 0.15 lb per million Btu heat input derived from combustion of fuel, based on a 30-day rolling average. [A.A.C. R18-2-406.A.4]

ii. 0.75 lb per million Btu heat input derived from combustion of fuel, on an hourly basis. [A.A.C. R18-2-406.A.5]

b. During periods of startup and shutdown, the Permittee shall not cause to be discharged into the atmosphere fro m the stack of Steam Boiler Unit 3, any gases which contain carbon monoxide in excess of 350 pounds per
hour. [A.A.C. R18-2-406.A.5]

2. Air Quality Control Requirements [A.A.C. R18-2-406.A.4]

a. At all times, including periods of startup, shutdown and malfunction, to the extent practicable, the Permittee shall operate and maintain Steam
Boiler Unit 3 and associated low NO

x burners in a manner consistent with good combustion practices fo r minimizing carbon monoxide

emissions. A.A.C. R18-2-306.A.3.a, 331.A.3.c and 406.A.4] [Material Permit Condition identified by underline and italics]

b. For the purpose of this Section, the good combustion practices shall include, but is not limited to, the following components:

i. Good air/fuel mixing in the combustion zone;

ii. High temperatures and low oxygen levels in the primary

co mbustion zone;

iii. Overall excess oxygen levels high enough to complete

co mbustion while maximizing boiler thermal efficiency; and

iv. Sufficient residence time to complete combustion.

c. Determination of whether the good combustion practices are being implemented for minimizing boiler carbon monoxide emissions will be
based on information available to th e Director which may include, but not limited to, monitoring results, re view of operation and maintenance procedures and records, and inspection of the source.TV Renewal Permit No. 53399 Page 64 of 109 May 31, 2012 APS-Cholla Generating Station 3. Monitoring, Recordkeeping and Reporting Requirements

a. The Permittee shall install, calibrate , maintain, and operate CEMS at each affected steam boiler unit , and record the output of the system, for measuring carbon monoxide (CO) and diluent (O 2 /CO 2 ) emissions from exhaust of the boiler’s stack . The output of the CEMS shall be expressed in pounds CO per million Btu heat input.
[ A.A.C. R18-2-306.A.3.a, 331.A.3.c and 406.A.4] [Material Permit Condition identified by underline and italics]

b. The existing diluent (O 2 /CO 2 ) continuous monitoring systems required under Sections IV.E. of Attachment “B” of the permit may be used to satisfy the requirement for monitoring of diluent emissions.

c. All continuous monitoring systems shall meet the following requirem ents: [A.A.C. R18-2-306.A.3.a and 406.A.4]

i. 40 CFR Part 75, Appendix A "Specification and Test
Procedures" for installation of the NO

x monitor shall be used for CO monitor by substituting NO

x for CO. Due to normal combustion variability, a dual range CO monitor shall be installed. The RATA specification shall be measured with 2 decimal places in lb CO per million BTU.

ii. 40 CFR Part 75, Appendix A, “Specification and Test
Procedures” f or CO and O 2 /CO 2 monitors

(1) Installation and measurement location

(2) Equipment specifications

(3) Performance specifications

(4) Data acquisition and handling systems

(5) Calibration gas

(6) Certifications tests and procedures

(7) Calculations

iii. 40 CFR Part 75, Appendix B, “Quality Assurance and Quality
Control Proce dure”

(1) Quality assurance/quality control program

(2) Frequency of testing

iv. 40 CFR Part 60 Appendix “F”, Quality Assurance Procedure for CO monitor for determining with pounds per hour emission rate
under Condition IV.G.1.b of this Attachment.

v. Data Reduction

The Permittee shall comply with the data reduction requirements of 40 CFR Part 75.10(d)(1).TV Renewal Permit No. 53399 Page 65 of 109 May 31, 2012 APS-Cholla Generating Station vi. Missing Data Substitution

(1) The Permittee shall, in processing any CO emission data gaps throu ghout operation, comply with the appropriate provisions in 40 CFR Part 75, Subpart D, “Missing Data
Substitution Procedures” and Appendix C, “Missing Data Estimation Procedures”. For the purpose of this Section, when monitor data availability reaches below 80%, all CO emission data ga ps shall be substituted using a CO emission rate not less than 0.75 lb per million Btu heat input derived from combustion of fuel.

(2) The Permittee may elect to supplement CO emission data
with the fo llowing USEPA reference methods and procedures:

(a) Reference Method 10 shall be used to determine
the CO conce ntration at the same location as the
CO monitor.

(b) The emission rate correction factor, integrated bag sam pling and analysis procedure of
Reference Method 3B shall be used to determine
the O 2 /CO 2 concentration at the same location as
the O 2 /CO 2 monitor.

(c) The procedures in Reference Method 19 shall be
used to com pute each 1-hour average concentration in ng/J (pounds per million Btu).

(d) As Method 19 does not provide conversion
factors for carbon m onoxide, a conversion factor
of 7.269×10 -8 shall be used to convert parts per million (ppm) to pounds per standard cubic foot (lb/scf).

vii. 40 CFR Part 75, Appendix F, “Conversion Procedures”

The Perm ittee shall convert all hour ly pollutant and diluent data to the applicable emissions sta ndard utilizing the procedures of 40 CFR Part 75, Appendix F.

d. Except for system breakdowns, repair s, calibration checks, and zero and span adjustments, each continuous m onitoring system prescribed in this Section shall complete a minimum of one cycle of operation (sampling, analyzing, and data recording) for each successive 15-minute period. [A.A.C. R18-2-306.A.3.a and 406.A.4]

e. CO Emissions Compliance Determination [A.A.C. R18-2-406.A.4 and 5]

i. The Permittee shall use CO emission data measured andTV Renewal Permit No. 53399 Page 66 of 109 May 31, 2012 APS-Cholla Generating Station recorded by the continuous m onitoring systems prescribed in this Section to demonstrate compliance with the carbon
monoxide emission standards set forth in Condition IV.G.1 of
this Attachment.

ii. Compliance with Condition IV.G.1.a.i of this Attachment shall be based on the average e mission rate for 30 successive calendar days. A new 30-day average carbon monoxide emission rate shall be determined at the end of each calendar day by calculating the arithmetic average of all hourly carbon monoxide emission rates for the past 30 successive calendar days, except for data obtained during periods of startup, shutdown, or
malfunction.

iii. The following shall be consid ered periods of excess emissions:

(1) Any calendar day for which the 30-day rolling average
CO emissio n rate, excluding periods of startup, shutdown, or malfunction, as determined by the applicable continuous monitoring systems in accordance with Condition IV.G.3.e.ii above exceeds the 30-day average CO emission limit set forth in Condition
IV.G.1.a.i of this Attachment.

(2) Any hour for which the hourly CO emission rate, excluding periods of startup, shutdown or malfunction, as measured by the applicable continuous monitoring systems of this Section exceeds the hourly CO emission
limit set forth in Condition IV.G.1.a.ii of this
Attachment.

(3) Any periods of startup, shutdown or malfunction, for which the CO emissions rate for any unit exceeds the
emission limit set forth in Condition IV.G.1.b of this
Attachment.

iv. All excess emissions shall be reported in accordance with Section XII, Attach ment “A” of the permit. [A.A.C. R18-2-306.A.5.b and 310.01]

f. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monito ring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other in formation required by this part recorded in a permanent form suitable for inspection. The file shall be retained for at least five years follo wing the date of such measurements, maintenance, reports, and records. [A.A.C. R18-2-306.A.4.a and 406.A.4]

V. STEAM BOILER UNIT 4

A. Applicability

This section applies to Unit 4 boiler as d escribed in Attachment “C” of this permit.TV Renewal Permit No. 53399 Page 67 of 109 May 31, 2012 APS-Cholla Generating Station B. Fuel Requirements

1. Fuel Limitation [Installation Permit No. 1085]

The Permittee shall burn only the foll owing fuels in Steam Boiler Unit 4:

a. Coal;

b. No. 2 fuel oil for startup and stabilization;

c. Co-firing of coal and used oil or used oil fuel subject to the requirements
set forth in C onditions V.B.2.a and b of this Attachment below.

2. Used Oil and Used Oil Fuel

a. Specifications

The used oil or used oil fuel a llowed to be burned shall meet the following conditions: [A.R.S. §49-426.G.1]

i. The flash point of the oil shall not fall below 100 °F;

ii. The oil shall not have following constituents in excess of the following all owable levels:

(1) Arsenic 5 ppm

(2) Cadmium 2 ppm

(3) Chromium 10 ppm

(4) Lead 100 ppm

(5) PCBs 2 ppm

(6) Total Halogens 1000 ppm

b. Limitations [A.R.S. §49-426.G.1]

(1) The Permittee shall not burn used oil and/or used oil fuel at a feed rate greater than twent y (20) gallons per minute while cofiring with coal in Steam Boiler Unit 4 at a minimum of 230 gross MW; and

(2) The Permittee shall not burn used oil and/or used oil fuel in excess of 200,000 gallons per year.

C. Operation Procedures

a. Startup

During startups of Steam Boiler Unit 4, the fabric filter shall be placed in service before startup of any boiler forced dr aft or induced draft fan. The fabric filter may be removed from service just pr ior to igniting oil fires (startup fuel) but must be returned to service before coal fires are placed in the boiler. TheTV Renewal Permit No. 53399 Page 68 of 109 May 31, 2012 APS-Cholla Generating Station lime slurry FGD system of the unit shall be placed in service after the fabric filter is placed in service, and before coal fires are in the boiler

. [40 CFR 60.11(d) and A.A.C. R18-2-331.A.3.e] [Material Permit Condi tion identified by underline and italics ] b. Shutdown

During shutdowns of Steam Boiler Unit 4, the fabric filter shall remain in service until after the boiler forced draft f ans and induced dra ft fans have been turned off. The lime slurry FGD system of the unit shall remain in service until coal fires in the boiler are out

. [40 CFR 60.11(d) and A.A.C. R18-2-331.A.3.e] [Material Permit Condi tion identified by underline and italics ] c. Malfunction

For Steam Boiler Unit 4 with any malfunction of its fabric filter that exceeds four hours, if fires are in the boiler, Pe rmittee shall reduce the unit’s load so that the fabric filter compartments in service can properly process and treat the volume of flue gas being produced. If a malfunction makes it impossible to properly process and treat the volume of fl ue gas being produced, the unit shall
be shut down. [40 CFR 60.11(d)]

D. Particulate Matter & Opacity

1. E mission Limits/Standards

a. Opacity

The opacity of emissions from the stack of Steam Boiler Unit 4 shall not be greater than 20 percent at all times except for periods of startup, shutdown, and malfunction as defined in Conditions I.A.1, 2 and 3 of this Attachment, and for one six-minute period per hour of not more than 27 percent opacity. Opacity readings of portions of plumes which contain condensed, uncombined water vapor shall not be used for purposes of determining compliance with the opacity standard

. [40 CFR 60.42(a)(2), 60.11(c) and 60.11(e)(1) and A.A.C. R18-2-331.A.3.a] [Material Permit Condition identified by underline and italics ]

b. Particulate Matter

The Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 4 any gases which contain particulate matter in excess of 43 nanogram per joule heat input (0.10 lb per million Btu) derived from fossil fuel. [40 CFR 60.42(a)(1)]

2. Air Pollution Control Requirements

At all times, including periods of startup, shutdown, and malfunction, the Permittee shall, to the extent practicable, operate and maintain Steam Boiler
Unit 4 and the fabric filter control device in a manner consistent with good air pollution control practice for minimizing particulate matter emissions . The Permittee shall inspect and maintain the fa bric filter control device in accordance with manufacturer specifications. [40 CFR 60.11(d) and A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]TV Renewal Permit No. 53399 Page 69 of 109 May 31, 2012 APS-Cholla Generating Station 3. Continuous Monitoring

a. The Permittee shall calibrate , maintain, and operate COMS for measuring the opacity of emissions. [40 CFR 60.45(a) and A. A.C. R18-2-331.A.3.c] [Material Permit Condition identifie d by underline and italics]

b. The continuous opacity monitori ng sy stem shall meet the following requirements:

i. 40 CFR 60, Appendix B, Performance Specification 1, “Specificatio n and Test Procedures for Opacity Continuous Emission Monitoring Systems in Stationary Sources”
[40 CFR 60.13] (1) Apparatus

(2) Installation Specifications

(3) Design and Performance Specifications

(4) Design Specifications Verification Procedure

(5) Performance Specifications Verification Procedure

(6) Equations

ii. Quality assurance requirements:

(1) Calibration Checks

The Perm ittee shall check the zero (or low-level value between 0 and 20% of span value) and span calibration drifts at least once daily in accordance with a written procedure. [40 CFR 60.13(d)(1)]

(2) Zero and Span Drift Adjustments

(a) The zero and span shall, as a minimum, be adjusted whenever the 24-hr zero drift or 24-hr span drift exceeds 4% opacity. [40 CFR 60.13(d)(1)]

(b) The system shall allow for the amount of excess zero and span drift measured at the 24-hour interval checks to be recorded and quantified. [40 CFR 60.13(d)(1)]

(c) The optical surfaces exposed to the effluent

gases shall be cleaned prior to performing the zero and span drift adjustments, except for systems using automatic zero adjustments. [40 CFR 60.13(d)(1)]

(d) For systems using automatic zero adjustments, the optical s urfaces shall be cleaned when the cumulative automatic zero compensation exceeds 4% opacity. [40 CFR 60.13(d)(1)]TV Renewal Permit No. 53399 Page 70 of 109 May 31, 2012 APS-Cholla Generating Station (3) System Checks

A method for producing a simulated zero opacity condition and an upscale (span) opacity condition using a certified neutral density filte r or other related technique to produce a known obscuration of the light beam to provide a system check of the analyzer internal optical surfaces and all electronic circuitry including the lamp and photo detector assembly shall be used by the
Permittee. [40 CFR 60.13(d)(2)]

(4) Minimum Frequency of Operation

Except during periods of system breakdowns, repairs, calibration checks, and zero and span adjustments, the COMS shall be in continuous operation and shall complete a minimum of one cycle of sampling and analyzing for each successive 10-second period and one cycle of data recording for each successive 6-minute period. [40 CFR 60.13(e)(1)]

(5) Data Reduction Procedures [40 CFR 60.13(h)]

(a) The Permittee shall reduce all data from the
COMS to 6-m inute averages. Six-minute opacity averages shall be calculated from 36 or more data points equally spaced over each 6- minute period.

(b) Data recorded during periods of system breakdowns, repairs, calibration che cks, and zero and span adjustments shall not be included in the data averages computed under the previous Condition. An arithmetic or integrated average of all data may be used.

4. Recordkeeping and Reporting Requirements

a. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monitoring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other information required by this section recorded in a permanent form suitable for inspection. The file shall be retained for at least five years following the date of such measurements, maintenance, reports and records. [40 CFR 60.7(f)]

b. The Permittee shall comply with all t he recordkeeping and reporting requirements of 40 CFR Part 75 Subparts F and G, respectively.
[40 CFR 60.7]

c. The Permittee shall record in a perm anent log for each shutdown, the date and time Steam Boiler Unit 4 intends to begin dropping load to goTV Renewal Permit No. 53399 Page 71 of 109 May 31, 2012 APS-Cholla Generating Station off line. The log shall be retained fo r at least five (5) years following the
date of each shutdown. [A.A.C. R18-2-306.A.4]

d. Quarterly excess emissions and monitoring system performance reports

i. The Permittee shall submit an excess emissions and monitoring systems performance (MSP) report and/or a summary report form to the Department for every calendar quarter, unless the
total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting period and the continuous monitoring system downtime for the reporting period is less than 5 per cent of the total operating time for the reporting period, in which case only the summary report
form shall be submitted and the excess emissions report need not be submitted unless requested by the Department. All quarterly reports shall be postmarked by th e 30th day following the end of each calendar quarter. [40 CFR 60.7(c) and (d), 45(g), 51Da(j) and 51Da(k)]

ii. The summary report form submission required in the preceding
Condition V.D.4.d.i shall be in the format specified in 40 CFR 60.7(d). Each excess emission and MSP report shall include the following information: [40 CFR 60.7(c)]

(1) The magnitude of excess emissions computed, any
conversion f actor(s) used, and the date and time of commencement and completion of each time period of excess emissions. The process operating time during the reporting period.

(2) Specific identification of each period of excess

e missions that occurs duri ng startups, shutdowns, and
malfunctions of the steam boiler unit. The nature and cause of any malfunction (if known), the corrective action taken or preventative measures adopted.

(3) The date and time identifying each period during which
the contin uous monitoring system was inoperative except for zero and span checks and the nature of the system repairs or adjustments.

(4) When no excess emissions have occurred or the
continuo us monitoring system(s) have not been inoperative, repaired, or adjusted, such information shall be stated in the report.

iii. Definitions

Periods of excess emissions and monitoring systems (MS) downtime that shall be reported are defined as follows:

Opacity excess emissions are defined as any six-minute period during which the average opacity of emissions from Steam Boiler Unit 4 stack exceeds 20 percent opacity as measured by a continuous opacity monitor, except that one six-minute averageTV Renewal Permit No. 53399 Page 72 of 109 May 31, 2012 APS-Cholla Generating Station per hour of up to 27 percent opacity need not be reported. [40 CFR 60.45(g)(1)] e. Emission deviations reporting requirements

In addition to the quarterly repor ting required under Condition V.C.3.d above, the Permittee shall report emissions exceeding an emission
limitation or standard as deviations in accordance with Section XII.B of Attachment “A” of this permit. [A.A.C. R18-2-306.A.5.b]

5. Performance Testing Requirements

a. Opacity

The Permittee shall perform an annual opacity observation of the stack of
Steam Boiler Unit 4 in accordance with EPA Reference Method 9. [40 CFR 60.8(a) and 46(b)(3)] b. Particulate Matter

The Permittee shall perform annual performance tests for emissions of particulate matter from the stack of Steam Boiler Unit 4, using the following reference methods and procedures: [40 CFR 60.8(a)]

i. Reference Method

EPA Reference Method 5 or 5B shall be used to determine the particulate matter concentration at the stack of Steam Boiler
Unit 4. [40 CFR 60.46(b)(2)]

ii. Emission Rate [40 CFR 60.46(b)(1)]

For the purpose of compliance determination, the emission rate (E) of PM shall be computed for each run using the following equation:

E = C F d (20.9)/(20.9 - %O 2 )

Or

E = C F

c (100/%CO 2 )

E = emission rate of pollutant, ng/J (1b/million Btu).

C = concentration of pollutant, ng/dscm (1b/dscf).

%O 2 = oxygen concentration, percent dry basis.

%CO 2 = carbon monoxide concentration, percent dry basis.

F d = factor as determined from Method 19

F
c = factor as determined in a ppropriate sections of Method 19.

c. The Permittee may conduct the annual performance tests using alternatives described in 40 CFR 60.46(d).

6. Compliance Assurance Mo nitoring f or Particulate Matter

The Permittee shall conduct complian ce assurance monitoring as required inTV Renewal Permit No. 53399 Page 73 of 109 May 31, 2012 APS-Cholla Generating Station Attachment “E” of this permit for Steam Boiler Unit 4. [40 CFR Part 64]

7. Used Oil and Used Oil Fuel Testing

The Permittee shall perform a semiannual samp le test for the used oil and/or used oil fuel to be burned for flash point and concentrations (ppm) of Arsenic, Cadmium, Chromium, Lead, and PCBs, using the analytical methods specified in EPA Publication SW-846, Third Editio n (document number 955-001-00000-1). All sample tests shall be conducted in the laboratories certified by the Arizona Department of Health Services. [A.R.S. §49-426.G.2]

8. Permit Shield

Co mpliance with the terms of this Secti on shall be deemed compliance with the applicable requirements prescribed under 40 CFR 60.42, 40 CFR 60.45, and 40 CFR 60.46 and 40 CFR Part 64 for the affected source subject to this Section.
[A.A.C. R18-2-325] E. Sulfur Dioxide

1. Emission Limits/Standards

The Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 4 any gases whic h contain sulfur dioxide in excess of 340 nanograms per joule heat input (0.8 pounds per million Btu) derived from solid or liquid fossil fuel. [A.A.C. R18-2-903.1 and 40 CFR 60.43(a)(1)]

2. Air Pollution Control Requirements

At all times, including periods of startup, shutdown, and malfunction, the Permittee shall, to the extent practicable, operate and maintain Steam Boiler
Unit 4 and the lime slurry FGD system in a manner consistent with good air pollution control practice for minimizing sulfur dioxide emissions . The Permittee shall inspect and maintain the FGD control device in accordance with manufacturer specifications. [Installation Permit No. 1247, 40 CFR 60. 11(d) and A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics ]

3. Continuous Monitoring SO 2 and O 2 /CO 2 Content

a. The Permittee shall calibrate, ma intain, and operate CEMS for measuring sulfur dioxide and O 2 /CO 2 emissions from the stack of Steam
Boiler Unit 4. [40 CFR 60.45(a) and A. A.C. R18-2-331.A.3.c] [Material Permit Condi tion identified by underline and italics]

b. The continuous emission monitoring systems for SO 2 and O 2 /CO 2 shall meet the following requirements:

i. 40 CFR Part 75, Appendix A, “Specification and Test
Procedures”
[A.A.C. R18-2-306.A.3.c]

(1) Installation and measurement location

(2) Equipment specifications

(3) Performance specificationsTV Renewal Permit No. 53399 Page 74 of 109 May 31, 2012 APS-Cholla Generating Station (4) Data acquisition and handling systems

(5) Calibration gas

(6) Certifications tests and procedures

(7) Calculations

ii. 40 CFR Part 75, Appendix B, “Quality Assurance and Quality
Control Procedure”

(1) Quality control program

(2) Frequency of testing

[A.A.C. R18-2-306.A.3.c]

iii. Data Reduction

The Permittee shall comply with the data reduction requirements
of 40 CFR Pa rt 75.10(d)(1). [ A.A.C. R18-2-306.A.3.c ]

iv. 40 CFR Part 75, Appendix F, “Conversion Procedures”
[A.A.C. R18-2-306.A.3.c]

The Permittee shall convert all hourly pollutant and diluent data to the applicable emissions standard utilizing the procedures of 40 CFR Part 75, Appendix F.

4. Recordkeeping and Reporting Requirements

a. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monitoring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other information required by this section recorded in a permanent form suitable for inspection. The file shall be retained for at least five years following the date of such measurements, maintenance, reports and records. [40 CFR 60.7(f)]

b. The Permittee shall comply with all t he recordkeeping and reporting requirements of 40 CFR Part 75 Subparts F and G, respectively.
[40 CFR 60.7]

c. The Permittee shall record in a perm anent log for each shutdown, the date and time Steam Boiler Unit 4 intends to begin dropping load to go off line. The log shall be retained fo r at least five (5) years following the
date of each shutdown. [A.A.C. R18-2-306.A.4]

d. Quarterly excess emissions and monitoring systems performance reports

i. The Permittee shall submit an excess emissions and monitoring systems performance (MSP) report and/or a summary report form to the Department for every calendar quarter, unless the
total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting period and the continuous monitoring system downtime for theTV Renewal Permit No. 53399 Page 75 of 109 May 31, 2012 APS-Cholla Generating Station reporting period is less than 5 per cent of the total operating time for the reporting period, in which case only the summary report
form shall be submitted and the excess emissions report need not be submitted unless requested by the Department. All quarterly reports shall be postmarked by th e 30th day following the end of each calendar quarter. [40 CFR 60.7(c) and (d) and 45(g)]

ii. The summary report form submission required in the preceding
Condition V.E.4.d.i shall be in the format specified in 40 CFR 60.7(d). Each excess emission and MSP report shall include the following information: [40 CFR 60.7(c)]

(1) The magnitude of excess emissions computed, any
conversion f actor(s) used, and the date and time of commencement and completion of each time period of excess emissions. The process operating time during the reporting period.

(2) Specific identification of each period of excess

e missions that occurs duri ng startups, shutdowns, and malfunctions of the affected facility. The nature and cause of any malfunction (if known), the corrective action taken or preventative measures adopted.

(3) The date and time identifying each period during which
the contin uous monitoring system was inoperative except for zero and span checks and the nature of the system repairs or adjustments.

(4) When no excess emissions have occurred or the
continuo us monitoring system(s) have not been inoperative, repaired, or adjusted, such information shall be stated in the report.

iii. Definitions

Periods of excess emissions and monitoring systems (MS) downtime that shall be reported is defined as follows:

SO 2 excess emissions are defined as any three-hour period during which the average SO 2 emissions from Steam Boiler Unit 4 stack (arithmetic average of three contiguous one-hour periods) as measured by a continuous monitoring system exceed 0.8 pound per million Btu, as specified in Condition V.E.3 of
this Attachment. [40 CFR 60.45(g)(2)]

e. Emission deviations reporting requirements

In addition to the quarterly repor ting required under Condition V.E.4.d above, the Permittee shall report emissions exceeding an emission
limitation or standard as deviations in accordance with Section XII.B of Attachment “A” of this permit. [A.A.C. R18-2-306.A.5.b]TV Renewal Permit No. 53399 Page 76 of 109 May 31, 2012 APS-Cholla Generating Station 5. Performance Testing Requirements

The Perm ittee shall perform annual perform ance tests for emissions of sulfur dioxide from the stack of Steam Boiler Unit 4, using the following reference methods and procedures: [40 CFR 60.8(a)]

a. Reference Method

EPA Reference Method 6 shall be used to determine the SO 2 concentration at the stack of Steam Boiler Unit 4. [40 CFR 60.46(b)(4)]

b. Emission Rate [40 CFR 60.46(b)(1)]

For the purpose of compliance determination, the emission rate (E) of
SO 2 shall be computed for each r un using the following equation:

E = C F d (20.9)/(20.9 - %O 2 )
Or

E = C F

c (100/%CO 2 )

E = emission rate of pollutant, ng/J (1b/million Btu).

C = concentration of pollutant, ng/dscm (1b/dscf).

%O 2 = oxygen concentration, percent dry basis.

%CO 2 = carbon monoxide concentration, percent dry basis.

F d = factor as determined from Method 19

F
c = factor as determined in a ppropriate sections of Method 19.

c. The Permittee may conduct the annual performance tests using alternatives described in 40 CFR 60.46(d).

6. Permit Shield

Co mpliance with the terms of this Secti on shall be deemed compliance with the applicable requirements prescribed under 40 CFR 60.43, 40 CFR 60.45, 40 CFR 60.46 and Installation permit #1247 for the affected sources subject to this
Section. [A.A.C. R18-2-325]

F. Nitrogen Oxide(s)

1. Emis sion Standards/Limitations

a. Coal

The Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 4 any gases which contain nitrogen oxides, expressed as NO 2 in excess of 300 nanogram per joule heat input (0.70 lb per million But) derived from solid fossil fuel. [40 CFR 60.44(a)(3)]

b. Combination Fuels

The Permittee shall not cause to be discharged into the atmosphere fromthe stack of Steam Boiler Unit 4, wh en different fossil fuels are burned simultaneously in any combination, any gases which contain nitrogen oxides in excess of the applicable standard (in ng/J) derived using the following prorating formula: [40 CFR 60.44(b)]



### zyxw z(300) y(130) x(86) w(260) PS NOx 

###    



Where:
PS NOx = prorated standard for nitrogen oxides when burning different fuels simultaneously, in nanograms per joule heat input derived
from all fossil fuels fired or from all fossil fuels and wood residue fired; w = percentage of total heat input derived from lignite;

x = percentage of total heat input derived from gaseous fossil fuel;

y = percentage of total heat in put derived from liquid fossil fuel; and

z = percentage of total heat input derived from solid fossil fuel (except lignite).

2. Air Quality Control Requirements

At all times including periods of startup, shutdown and malfunction, to the extent practicable, the Permittee shall operate and maintain Steam Boiler Unit 4 and
associated low NO

x burners in a manner consistent with good air pollution control practice for minimizing nitrogen oxides emissions . The Permittee shall inspect and maintain the low NO

x burners in accordance with manufacturer specifications. [A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

3. Continuous Monitoring NO

x Emissions

a. The Permittee shall calibrate , maintain and operate CEMS for measuring nitrogen oxide (NO

x ) emissions from the stack of Steam Boiler Unit 4.
[A.A.C. R18-2-306.A.3.c, A.A.C. R18-2-331.A.3.c] [Material Permit Condi tion identified by underline and italics]

b. The continuous emission monitoring systems for NO

x shall meet the following requirements:

i. 40 CFR Part 75, Appendix A, “Specification and Test
Procedures” [A.A.C. R18-2-306.A.3.c]

(1) Installation and measurement location

(2) Equipment specifications

(3) Performance specifications

(4) Data acquisition and handling systems

(5) Calibration gas

(6) Certifications tests and procedures

(7) Calculations

TV Renewal Permit No. 53399 Page 77 of 109 May 31, 2012 APS-Cholla Generating StationTV Renewal Permit No. 53399 Page 78 of 109 May 31, 2012 APS-Cholla Generating Station ii. 40 CFR Part 75, Appendix B, “Quality Assurance and Quality
Control Proce dure” [A.A.C. R18-2-306.A.3.c]

(1) Quality control program

(2) Frequency of testing

iii. Data Reduction [A.A.C. R18-2-306.A.3.c]

The Permittee shall comply with the data reduction requirements of 40 CFR Part 75.10(d)(1).

iv. 40 CFR Part 75, Appendix F, “Conversion Procedures”
[A.A.C. R18-2-306.A.3.c]

The Permittee shall convert all hourly pollutant and diluent data to the applicable emissions standard utilizing the procedures of 40 CFR Part 75, Appendix F.

4. Recordkeeping and Reporting Requirements

a. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monitoring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other information required by this section recorded in a permanent form suitable for inspection. The file shall be retained for at least five years following the date of such measurements, maintenance, reports and records. [40 CFR 60.7(f)]

b. The Permittee shall comply with all t he recordkeeping and reporting requirements of 40 CFR Part 75 Subparts F and G, respectively.
[40 CFR 60.7]

c. The Permittee shall record in a perm anent log for each shutdown, the date and time Steam Boiler Unit 4 intends to begin dropping load to go off line. The log shall be retained fo r at least five (5) years following the
date of each shutdown. [A.A.C. R18-2-306.A.4]

d. Quarterly excess emissions and monitoring systems performance reports

i. The Permittee shall submit an excess emissions and monitoring systems performance (MSP) report and/or a summary report form to the Department for every calendar quarter, unless the
total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting period and the continuous monitoring system downtime for the reporting period is less than 5 per cent of the total operating time for the reporting period, in which case only the summary report
form shall be submitted and the excess emissions report need not be submitted unless requested by the Department. All quarterly reports shall be postmarked by th e 30th day following the end of each calendar quarter. [40 CFR 60.7(c) and (d) and 45(g)]TV Renewal Permit No. 53399 Page 79 of 109 May 31, 2012 APS-Cholla Generating Station ii. The summary report form submission required in the preceding
Condition V.F.4.d.i shall be in the format specified in 40 CFR 60.7(d). Each excess emission and MSP report shall include the following information: [40 CFR 60.7(c)]

(1) The magnitude of excess emissions computed, any
conversion f actor(s) used, and the date and time of commencement and completion of each time period of excess emissions. The process operating time during the reporting period.

(2) Specific identification of each period of excess

e missions that occurs duri ng startups, shutdowns, and malfunctions of the affected facility. The nature and cause of any malfunction (if known), the corrective action taken or preventative measures adopted. (3) The date and time identifying each period during which
the contin uous monitoring system was inoperative except for zero and span checks and the nature of the system repairs or adjustments.

(4) When no excess emissions have occurred or the
continuo us monitoring system(s) have not been inoperative, repaired, or adjusted, such information shall be stated in the report.

f. Emission deviations reporting requirements

In addition to the quarterly reporting required under Condition V.F.4.d above, the Permittee shall report emissions exceeding an emission
limitation or standard as deviations in accordance with Section XII.B of Attachment “A” of this permit. [A.A.C. R18-2-306.A.5.b]

5. Performance Testing Requirements

The Perm ittee shall perform annual perfor mance tests for emissions of nitrogen oxides from the stack of Steam Boiler Unit 4, using the following reference methods and procedures: [40 CFR 60.8(a)]

a. Reference Method

EPA Reference Method 7 shall be used to determine the NO

x concentration at the stack of Steam Boiler Unit 4. [40 CFR 60.46(b)(5)]

b. Emission Rate [40 CFR 60.46(b)(1)]

For the purpose of compliance determination, the emission rate (E) of
NO

x shall be computed for each r un using the following equation:

E = C F d (20.9)/(20.9 - %O 2 )

Or

E = C F

c (100/%CO 2 )TV Renewal Permit No. 53399 Page 80 of 109 May 31, 2012 APS-Cholla Generating Station E = emission rate of pollutant, ng/J (1b/million Btu).

C = concentration of pollutant, ng/dscm (1b/dscf).

%O 2 = oxygen concentration, percent dry basis.

%CO 2 = carbon monoxide concentration, percent dry basis.

F d = factor as determined from Method 19

F
c = factor as determined in a ppropriate sections of Method 19.

c. The Permittee may conduct the annual performance tests using alternatives described in 40 CFR 60.46(d).

6. Permit Shield

Co mpliance with the terms of this Secti on shall be deemed compliance with the applicable requirements prescribed under 40 CFR 60.44, and 40 CFR 60.46 for the affected source subject to this Section. [A.A.C. R18-2-325]

G. Carbon Monoxide

1. Emission Limitations/Standards



### a. At all times, excluding periods of startup and shutdown, the Permittee shall not cause to be discharged into the atmosphere from the stack of Steam Boiler Unit 4, any gases which contain carbon monoxide in excess
of:

i 0.15 lb per million Btu heat input derived from combustion of fuel, based on a 30-day rolling average. A.A.C. R18-2-406.A.4 ]

ii. 0.75 lb per million Btu heat input derived from combustion of fuel, on an hourly basis. [A.A.C. R18-2-406.A.5]

b. During periods of startup and shutdown, the Permittee shall not cause to be discharged into the atmosphere fro m the stack of Steam Boiler Unit 4, any gases which contain carbon monoxide in excess of 400 pounds per
hour. [A.A.C. R18-2-406.A.5]

2. Air Quality Control Requirements [A.A.C. R18-2-406.A.4]

a. At all times, including periods of startup, shutdown and malfunction, to the extent practicable, the Permittee shall operate and maintain Steam
Boiler Unit 4 and associated low NO

x burners in a manner consistent with good combustion practices fo r minimizing carbon monoxide

emissions. A.A.C. R18-2-306.A.3.a, 331.A.3.c and 406.A.4] [Material Permit Condition identified by underline and italics]

b. For the purpose of this Section, the good combustion practices shall include, but is not limited to, the following components:

i. Good air/fuel mixing in the combustion zone;

ii. High temperatures and low oxygen levels in the primary

co mbustion zone;TV Renewal Permit No. 53399 Page 81 of 109 May 31, 2012 APS-Cholla Generating Station iii. Overall excess oxygen levels high enough to complete combustion while maximizing boiler thermal efficiency; and

iv. Sufficient residence time to complete combustion.

c. Determination of whether the good combustion practices are being implemented for minimizing boiler carbon monoxide emissions will be
based on information available to th e Director which may include, but not limited to, monitoring results, re view of operation and maintenance procedures and records, and inspection of the source.

3. Monitoring, Recordkeeping and Reporting Requirements

a. The Permittee shall install, calibrate , maintain, and operate CEMS at each affected steam boiler unit , and record the output of the system, for measuring carbon monoxide (CO) and diluent (O 2 /CO 2 ) emissions from exhaust of the boiler’s stack . The output of the CEMS shall be expressed in pounds CO per million Btu heat input.
[ A.A.C. R18-2-306.A.3.a, 331.A.3.c and 406.A.4] [Material Permit Condition identified by underline and italics]

b. The existing diluent (O 2 /CO 2 ) continuous monitoring systems required under Sections V.E. of Attachment “B” of the permit may be used to satisfy the requirement for monitoring of diluent emissions.

c. All continuous monitoring systems shall meet the following requirem ents: [A.A.C. R18-2-306.A.3.a and 406.A.4]

i. 40 CFR Part 75, Appendix A "Specification and Test
Procedures" for installation of the NO

x monitor shall be used for CO monitor by substituting NO

x for CO. Due to normal combustion variability, a dual range CO monitor shall be installed. The RATA specification shall be measured with 2 decimal places in lb CO per million BTU.

ii. 40 CFR Part 75, Appendix A, “Specification and Test
Procedures” f or CO and O 2 /CO 2 monitors

(1) Installation and measurement location

(2) Equipment specifications

(3) Performance specifications

(4) Data acquisition and handling systems

(5) Calibration gas

(6) Certifications tests and procedures

(7) Calculations

iii. 40 CFR Part 75, Appendix B, “Quality Assurance and Quality
Control Proce dure”

(1) Quality assurance/quality control program

(2) Frequency of testingTV Renewal Permit No. 53399 Page 82 of 109 May 31, 2012 APS-Cholla Generating Station iv. 40 CFR Part 60 Appendix “F”, Quality Assurance Procedure for CO monitor for determining with pounds per hour emission rate
under Condition V.G.1.b of this Attachment.

v. Data Reduction

The Permittee shall comply with the data reduction requirements of 40 CFR Part 75.10(d)(1).

vi. Missing Data Substitution

(1) The Permittee shall, in processing any CO emission data gaps throu ghout operation, comply with the appropriate provisions in 40 CFR Part 75, Subpart D, “Missing Data
Substitution Procedures” and Appendix C, “Missing Data Estimation Procedures”. For the purpose of this Section, when monitor data availability reaches below 80%, all CO emission data ga ps shall be substituted using a CO emission rate not less than 0.75 lb per million Btu heat input derived from combustion of fuel.

(2) The Permittee may elect to supplement CO emission data
with the fo llowing USEPA reference methods and procedures:

(a) Reference Method 10 shall be used to determine
the CO conce ntration at the same location as the
CO monitor.

(b) The emission rate correction factor, integrated bag sam pling and analysis procedure of
Reference Method 3B shall be used to determine
the O 2 /CO 2 concentration at the same location as
the O 2 /CO 2 monitor.

(c) The procedures in Reference Method 19 shall be
used to com pute each 1-hour average concentration in ng/J (pounds per million Btu).

(d) As Method 19 does not provide conversion
factors for carbon m onoxide, a conversion factor
of 7.269×10 -8 shall be used to convert parts per million (ppm) to pounds per standard cubic foot (lb/scf).

vii. 40 CFR Part 75, Appendix F, “Conversion Procedures”

The Perm ittee shall convert all hour ly pollutant and diluent data to the applicable emissions sta ndard utilizing the procedures of 40 CFR Part 75, Appendix F.

d. Except for system breakdowns, repair s, calibration checks, and zero and span adjustments, each continuous m onitoring system prescribed in thisTV Renewal Permit No. 53399 Page 83 of 109 May 31, 2012 APS-Cholla Generating Station Section shall complete a minimum of one cycle of operation (sampling, analyzing, and data recording) for each successive 15-minute period. [A.A.C. R18-2-306.A.3.a and 406.A.4]

e. CO Emissions Compliance Determination [A.A.C. R18-2-406.A.4 and 5]

i. The Permittee shall use CO emission data measured and recorded by the continuous m onitoring systems prescribed in this Section to demonstrate compliance with the carbon
monoxide emission standards set forth in Condition IV.G.1 of
this Attachment.

ii. Compliance with Condition V.G.1.a.i of this Attachment shall be based on the average e mission rate for 30 successive calendar days. A new 30-day average carbon monoxide emission rate shall be determined at the end of each calendar day by calculating the arithmetic average of all hourly carbon monoxide emission rates for the past 30 successive calendar days, except for data obtained during periods of startup, shutdown, or
malfunction.

iii. The following shall be consid ered periods of excess emissions:

(1) Any calendar day for which the 30-day rolling average
CO emissio n rate, excluding periods of startup, shutdown, or malfunction, as determined by the applicable continuous monitoring systems in accordance with Condition V.G.3.e.ii above exceeds the 30-day average CO emission limit set forth in Condition
V.G.1.a.i of this Attachment.

(2) Any hour for which the hourly CO emission rate, excluding periods of startup, shutdown or malfunction, as measured by the applicable continuous monitoring systems of this Section exceeds the hourly CO emission
limit set forth in Condition V.G.1.a.ii of this Attachment.

(3) Any periods of startup, shutdown or malfunction, for which the CO emissions rate for any unit exceeds the
emission limit set forth in Condition V.G.1.b of this
Attachment.

iv. All excess emissions shall be reported in accordance with Section XII, Attach ment “A” of the permit. [A.A.C. R18-2-306.A.5.b and 310.01]

f. The Permittee shall maintain a f ile o f all measurements, including continuous monitoring system, monitoring device, and performance testing measurements; all continuous monitoring system performance evaluations; all continuous monito ring system or monitoring device calibration checks; adjustments a nd maintenance performed on these systems or devices; and all other in formation required by this part recorded in a permanent form suitable for inspection. The file shall be retained for at least five years follo wing the date of such measurements, maintenance, reports, and records. [A.A.C. R18-2-306.A.4.a and 406.A.4]TV Renewal Permit No. 53399 Page 84 of 109 May 31, 2012 APS-Cholla Generating Station VI. COOLING TOWERS 3 AND 4

A. Applicability

This section applies to Cooling Towers #3 and #4 as described in Attachment “C” of this permit.

B. Opacity Requirements

1. Emission Limits

The Perm ittee shall not cause, allow or permit to be emitted into the atmosphere any plume or effluent from Cooling Tower 3 or 4 the opacity of which exceeds 20 percent, measured in accordance with EPA Reference Method 9. Where the presence of uncombined water is the onl y reason for an exceedance of any visible emissions requirements, such exceedance shall not constitute a violation. [A.A.C. R18-2-702.B.3 and C]

2. Monitoring, Recordkeeping and Reporting Requirements

The Perm ittee shall conduct a weekly Vi sible Emissions Observation Procedure for the cooling towers consistent with C ondition I.H of this Attachment.
[A.A.C. R18-2-306.A.3.c] 3. Permit Shield

Compliance with this Section shall be deemed compliance with A.A.C. R18-2-
702.B and C for the affect ed sources subject to this Section. [A.A.C. R18-2-325]

C. Particulate Matter

1. Emission Limits/Standards

The Permittee shall not cause, allow or permit the emission of particulate matter from Cooling Tower 3 or 4 in excess of the amounts calculated by the following equation: [A.A.C. R18-2-730.A.1(b)]

E = 55.0 P 0.11 – 40

Where:

E = The maximum allowable particul ate emissions rate in pounds-mass per hour;

P = The process weight rate in tons-mass per hour. The total process weight from all similar units employing a similar type process shall be used in determining the maximum allowable emission of particulate matter.

2. Monitoring, Recordkeeping and Reporting Requirements

The Permittee shall conduct a weekly Visible Emissions Observation Procedure for the cooling towers consistent with Condition I.H of this Attachment.
[A.A.C. R18-2-306.A.3.c] 3. Permit Shield

Compliance with this Section shall be deemed compliance with A.A.C. R18-2-TV Renewal Permit No. 53399 Page 85 of 109 May 31, 2012 APS-Cholla Generating Station 730.A.1(b) for the affected sources subject to this Section. [A.A.C. R18-2-325]

VII. COAL PREPARATION PLANT

A. Equipment Subject to A.A.C Rules

1. Applicability

This section is applicable to all equipm ent in the Coal Preparation Plant except the Coal Handling System -New Track as described in the equipment list in Attachment “C” of this permit.

2. Opacity

a. Emission Limits/Standards

The Permittee shall not cause, allow or permit to be emitted into the atmosphere any plume or effluent from the equipment covered by this section, the opacity of which exceeds 20 percent, measured in accordance with EPA Reference Method 9. Where the presence of uncombined water is the only reason for an exceedance of any visible emissions requirements, such exceedance shall not constitute a violation. [A.A.C. R18-2-702.B.3 and C]

b. Monitoring, Recordkeeping and Reporting Requirements

The Permittee shall conduct a week ly Visible Emissions Observation Procedure for any point source, non-point sources, or fugitive emissions for the equipment covered by this S ection consistent with Condition I.H
of this Attachment. [A.A.C. R18-2-306.A.3.c]

3. Particulate Matter

a

. Emission Limits/Standards [A.A.C. R18-2-716.B & D]

The Permittee shall not cause, allow or permit the discharge of particulate matter into the atmosphere in any one hour from the equipment covered by this section in total quantities in excess of the amounts calculated by the following equation:

E = 55.0 P 0.11 – 40

Where:

E = The maximum allowable particulate emissions rate in poundsmass per hour.

P = The process weight rate in t ons-mass per hour. The total process weight from all similar units employing a similar type process shall be used in determining the maximum allowable emissions of particulate matter.

b. Air Pollution Control Requirements

i. The Permittee shall operate and maintain waterTV Renewal Permit No. 53399 Page 86 of 109 May 31, 2012 APS-Cholla Generating Station spraying/chemical dust suppression at the feeders during railcar unloading, at the screen feeders during screening, and at the coal piles during stockpiling in a manner consistent with good air pollution control practice for minimizing particulate matter emissions from the coal preparation plant

. [Installation Permit No. 1160 & A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

ii. The Permittee shall operate and maintain dust collectors for Crusher Tower #1, Crusher Tower #2, and Transfer Tower #3, in a manner consistent with goo d air pollution control practice for minimizing particulate emissions. [Installation Permit No. 1160 & A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

iii. The water spraying/chemical dust suppressing system and dust collectors for the coal preparation plant shall be operated and
maintained in accordan ce with the manufacturer’s specifications. These specifications shall be on file and shall be readily available for inspection by the Department.
[A.A.C. R18-2-306.A.3.c]

iv. The Permittee shall maintain records of emissions control equipment maintenance performed on the water spraying/chemical dust suppressing system and dust collectors.
[A.A.C. R18-2-306.A.3.c] 4. Permit Shield

Compliance with the terms of this Sec tion shall be deemed compliance with
A.A.C. R18-2-702.B and 716.B and D and Installation Permit No. 1160 for the sources subject to this Section. [A.A.C. R18-2-325]

B. Equipment subject to New Source Performance Standards (New Track Unloading Hopper and Conveyor 12A)

1. Applicability

This section is applicable to all equi pment under the Coal Handling System – New Track as described in the equipment list in Attachment “C” of this permit.

2. Opacity

a. Emission Limitation/Standards

The Permittee shall not cause to be emitted to the atmosphere from the equipment covered by this section, ga ses which exhibit opacity greater 20

percent

. [40 CFR 60.252(c) & A.A.C. R18-2-331.A.3.f] [Material Permit Condition identified by underline and italics]

b. Air Pollution Control Requirements

The Permittee shall operate and maintain water spraying/chemical dust suppression at the feeders during rail car unloading and at the drop point of Conveyor 12A in a manner consistent with good air pollution control practice for minimizing particulate matter emissions.
[A.A.C. R18-2-306.A.2 & A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]TV Renewal Permit No. 53399 Page 87 of 109 May 31, 2012 APS-Cholla Generating Station c. Monitoring, Recordkeeping, and Reporting Requirements

i. The Permittee shall conduct a weekly Visible Emissions Observation Procedure for the equipment covered by this
Section consistent with Condition I.H of this Attachment.
[A.A.C. R18-2-306.A.3.c]

ii. The water spraying/chemical dust suppressing system and dust collectors for the coal preparation plant shall be operated and
maintained in accordance with th e manufacturer’s specifications. These specifications shall be on file and shall be readily available for inspection by the Department.
[A.A.C. R18-2-306.A.3.c]

iii. The Permittee shall maintain records of emissions control equipment maintenance performed on the water spraying/chemical dust suppressing system and dust collectors.
[A.A.C. R18-2-306.A.3.c]

d. Performance Testing Requirements

The Permittee shall conduct initial performance tests for opacity in accordance with the provisions of 40 CFR 60.8. [A.A.C. R18-2-312 ]

VIII. FLY ASH HANDLING FACILITY

A. Applicability

This section applies to fly ash handling equipm ent as described in Attachment “C” of this permit.

B. Opacity

1. Emission Limits/Standards

The Perm ittee shall not cause, allow or permit to be emitted into the atmosphere any plume or effluent from the fly ash s ilo vent the opacity of which exceeds 20 percent, measured in accordance with EPA Reference Method 9. Where the presence of uncombined water is the onl y reason for an exceedance of any visible emissions requirements, such exceedance shall not constitute a violation. [A.A.C. R18-2-702.B.3 and C]

2. Monitoring, Recordkeeping and Reporting Requirements

The Permittee shall conduct a weekly Visible Emissions Observation Procedure for any point/non-point sources, or fugitive emissions at the fly ash handling facility consistent with Condition I.H of this Attachment. [A.A.C. R18-2-306.A.3.c]

C. Particulate Matter

1. Emission Limits/Standards

The Perm ittee shall not cause, allow or permit the discharge of particulate matter into the atmosphere in any one hour fro m the fly ash silo baghouse exhaust vent in total quantities in excess of the amount s calculated by the following equation:TV Renewal Permit No. 53399 Page 88 of 109 May 31, 2012 APS-Cholla Generating Station E = 55.0 P 0.11 – 40

Where: E = the maximum allowable particulate emissions rate in pounds-mass per hour.

P = the process weight rate in tons-mass per hour. [A.A.C. R18-2-730.A.1.b and B] 2. Air Pollution Control Requirements

The Permittee shall operate and maintain at all times the baghouse in a manner consistent with good air pollution control practice for minimizing particulate matter emissions from the fly ash silo vent . The Permittee shall inspect and
maintain the fabric filter control device in accordance with manufacturer specifications. [Installation Permit No. 1244, A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

3. Monitoring, Recordkeeping and Reporting Requirements

a. The Permittee shall maintain and op erate the fly ash silo baghouse in
accordance with the manufacturer’s sp ecification. These specifications shall be on file and shall be readily available for inspection by the Department. [Installation Permit No. 1244]

b. The Permittee shall maintain reco rds of em issions control equipment maintenance performed on the fly ash silo baghouse. [Installation Permit No. 1244] D. Permit Shield

Compliance with the terms of this Section shall be deemed compliance with A.A.C. R18- 2-702.B, A.A.C. R18-2-730.A.1.b and B, and Installation Permit No. 1244 for the affected sources subject to this Section. [A.A.C. R18-2-325]

IX. LIME HANDLING AND SLAKING

A. Applicability

This section applies to Lime handling and Slaking equipment as described in Attachment “C” of this permit.

B. Opacity

1. Emission Limits/Standards

The Perm ittee shall not cause, allow or permit to be emitted into the atmosphere any plume or effluent from the lime s ilo baghouse exhaust vent or the lime slaking wet scrubber exhaust vent the op acity of which exceeds 20 percent,
measured in accordance with EPA Refere nce Method 9. Where the presence of uncombined water is the only reason for an exceedance of any visible emissions requirements, such exceedance shall not constitute a violation. [A.A.C. R18-2-702.B.3 and C]

2. Monitoring, Recordkeeping and Reporting Requirements

The Permittee shall conduct a weekly Visible Emissions Observation Procedure for any point/non-point sources, or fugitiv e emissions at the lime handling andTV Renewal Permit No. 53399 Page 89 of 109 May 31, 2012 APS-Cholla Generating Station slaking facility consistent with Condition I.H of this attachment.
[A.A.C. R18-2-306.A.3.c]

3. Permit Shield

Compliance with the terms of this Sec tion shall be deemed compliance with A.A.C. R18-2-702.B for the affected sources subject to this Section.
[A.A.C. R18-2-325] C. Particulate Matter

1. Emission Limits/Standards

The Permittee shall not cause, allow or permit the discharge of particulate matter into the atmosphere in any one hour from the lime silo baghouse exhaust vent or the lime slaking wet scrubber exhaust vent in total quantities in excess of the amounts calculated by the following equation: [A.A.C. R18-2-730.A.1.a and B]

E = 4.10 P 0.67

Where:

E = the maximum allowable particulate emissions rate in pounds-mass per hour.

P = the process weight rate in tons-mass per hour.

2. Air Pollution Control Requirements

The Permittee shall, during operation of the lime handling and slaking facility

, operate and maintain a wet scrubber on the vent of each operating lime slaker and a baghouse on the vent of each operating lime silo in a manner consistent with good air pollution control practice for minimizing particulate matter emissions from those vents

. The Permittee shall inspect and maintain the wet scrubber control device in accordance with manufacturer specifications. [Installation Permit No. 1247, A.A.C. R18-2-331.A.3.e] [Material Permit Condition identified by underline and italics]

3. Monitoring, Recordkeeping and Reporting Requirements
[A.A.C. R18-2-306.A.4] a. The Permittee shall maintain a nd operate the lime silos baghouse and
lime slaker vent wet scrubber in accordance with the manufacturer’s specification. These specifications shall be on file and shall be readily available for inspection by the Department.

b. The Permittee shall maintain reco rds of em issions control equipment maintenance performed on the lime silo baghouse and lime slaker vent
wet scrubber.

4. Permit Shield

Compliance with the terms of this Sec tion shall be deemed compliance with
A.A.C. R18-2-730.A.1.a and B and Insta llation Permit No. 1247 for the affected sources subject to this Section.
[A.A.C. R18-2-325]TV Renewal Permit No. 53399 Page 90 of 109 May 31, 2012 APS-Cholla Generating Station X. FUGITIVE DUST SOURCES

A. Emission Limits/Standards

1. Open Areas, Roadways & Streets, Storage Piles, and Material Handling

a. Opacity of emissions from any fugitive dust non-point source shall not be greater than 40% measured in accordance with the Arizona Testing Manual, Reference Method 9. [A.A.C. R18-2-614]

b. The Permittee shall not cause, allow or permit visible emissions from any fugitive dust point source, in excess of 20 percent opacity.
[A.A.C-R18-2-702.B]

c. The Permittee shall employ the following reasonable precautions to prevent excessive amounts of particulate matter from becoming airborne:

i. Keep dust and other types of air contaminants to a minimum in

an open area where constructi on operations, repair operations, demolition activities, clearing opera tions, leveling operations, or any earth moving or excavating activities are taking place, by good modern practices such as using an approved dust suppressant or adhesive soil st abilizer, paving, covering, landscaping, continuous wetting, detouring, barring access, or other acceptable means; [A.A.C. R18-2-604.A]

ii. Keep dust to a minimum from driveways, parking areas, and
vacant lots where motor vehicula r activity occurs by using an approved dust suppressant, or adhesive soil stabilizer, or by paving, or by barring access to the property, or by other acceptable means; [A.A.C. R18-2-604.B]

iii. Keep dust and other particulates to a minimum by employing dust suppressants, tem porary paving, detouring, wetting down or by other reasonable means when a roadway is repaired, constructed, or reconstructed; [A.A.C. R18-2-605.A]

iv. Take reasonable precautions, such as wetting, apply ing dust suppressants, or covering the load when transporting material likely to give rise to airborne dust; [A.A.C. R18-2-605.B]

v. Take reasonable precautions, such as the use of spray bars, wetting agents, dust suppr essants, covering the load, and hoods when crushing, handling, or conveying material likely to give rise to airborne dust; [A.A.C. R18-2-606]

vi. Take reasonable precautions such as chemical stabilization, wetting, or covering whe n organic or inorganic dust producing material is being stacked, piled, or otherwise stored;
[A.A.C. R18-2-607.A]

vii. Operate stacking and reclaiming machinery utilized at storage piles at all ti mes with a minimum fall of material, or with the use of spray bars and wetting agents; [A.A.C. R18-2-607.B]TV Renewal Permit No. 53399 Page 91 of 109 May 31, 2012 APS-Cholla Generating Station viii. Any other method as proposed by the Permittee and approved by
the Director. [A.A.C. R18-2-306.A.3.c]

2. Open Burning

Except as provided in A.A.C. R18-2-602.C(1), C(3), and C(4), and except when permitted to do so by either ADEQ or the local officer delegated the authority for issuance of open burning permits the Perm ittee shall not conduct open burning.
[A.A.C. R18-2-602]

B. Monitoring, Recordkeeping and Reporting Requirements

1. Open Areas, Roadways & Streets, Storage Piles and Material Handling

The Perm ittee shall maintain records of the dates on which any of the activities listed in Conditions X.A.1.c.i through viii of this Attachment were performed and control measures adopted. [A.A.C. R18-2-306.A.4]

2. Weekly Opacity Survey

The Perm ittee shall conduct a weekly Visible Emissions Observation Procedure for all fugitive dust sources at open areas, ro adways and streets, storage piles and material handling facilities consistent w ith Condition I.H of this Attachment.
[A.A.C. R18-2-306.A.3.c] 3. Open Burning

The monitoring requirements for open burning may be complied with by maintaining copies of all open burning permits on file. [A.A.C. R18-2-306.A.4]

C. Permit Shield

Co mpliance with the conditions of this Part shall be deemed compliance with A.A.C. R18-2-604.A, A.A.C. R18-2-604.B, A.A.C. R18-2-605, A.A.C. R18-2-606, A.A.C. R18- 2-607, A.A.C. R18-2-614 and A.A.C. R18-2-702.B. [A.A.C. R18-2-325]

XI. MOBILE SOURCE REQUIREMENTS

A. Applicability

The requirements of this Section are applicable to mobile sources which either move while emitting air contaminants or are freque ntly moved during the course of their
utilization but are not classified as motor vehi cles, agricultural vehicles, or agricultural equipment used in normal farm operations. Mobile sources shall not include portable
sources as defined in A.A.C. R18-2-101.90. [A.A.C.R18-2-801.A]

B. Particulate Matter and Opacity

1

. Emission Limitations/Standards

a. Off-Road Machinery

The Permittee shall not cause, allow, or permit to be emitted into the atmosphere from any off-road machinery, smoke for any period greater than ten consecutive seconds, the opacity of which exceeds 40%. Visible emissions when starting cold equipment shall be exempt from this requirement for the first ten minutes. Off-road machinery shall includeTV Renewal Permit No. 53399 Page 92 of 109 May 31, 2012 APS-Cholla Generating Station trucks, graders, scrapers, rollers, and other construction and mining machinery not normally driven on a completed public roadway. [A.A.C.R18-2-802.A and -802.B] b. Roadway and Site Cleaning Machinery

(1) The Permittee shall not cause, allow or permit to be emitted into the atmosphere from any roadwa y and site cleaning machinery smoke or dust for any period greater than ten consecutive seconds, the opacity of which exceeds 40%. Visible emissions when starting cold equipment shall be exempt from this requirement for the first ten minutes. [A.A.C.R18-2-804.A]

(2) The Permittee shall take reasona ble precautions, such as the use of dust suppressants, before the cleaning of a site, roadway, or alley. Earth or other materi al shall be removed from paved streets onto which earth or other material has been transported by trucking or earth moving equipment, erosion by water or by
other means. [A.A.C. R18-2-804.B]

c. Unless otherwise specified, no mobile source shall emit smoke or dust the opacity of which exceeds 40%. [A.A.C.R18-2-801.B]

2

. Recordkeeping Requirement

The Permittee shall keep a record of a ll emissions related maintenance activities performed on the Permittee's mobile sources stationed at the facility as per manufacturer's specifications. [A.A.C.R18-2-306.A.5.a]

3

. Permit Shield

Compliance with the conditions of this Part shall be deemed compliance with A.A.C. R18-2-801, A.A.C. R18-2-802.A, A.A.C. R18-2-802.B, A.A.C. R18-2-
804.A and A.A.C. R18-2-804.B. [A.A.C.R18-2-325]

XII. OTHER PERIODIC ACTIVITIES

A. Abrasive Blasting

1. Particulate Matter and Opacity

a. Emission Limitations/Standards

The Permittee shall not cause or allow sandblasting or other abrasive blasting without minimizing dust emis sions to the atmosphere through the use of good modern practices. Good modern practices include:

(1) Wet blasting;

(2) Effective enclosures with necessary dust collecting equipment;

(3) Any other method approved by the Director.
[A.A.C. R18-2-726] b. OpacityTV Renewal Permit No. 53399 Page 93 of 109 May 31, 2012 APS-Cholla Generating Station The Permittee shall not cause, allow or permit visible emissions from sandblasting or other abrasive blasting operations in excess of 20% opacity, as measured by EPA Reference Method 9. [A.A.C. R18-2-702.B]

2. Monitoring and Recordkeeping Requirement

Each time an abrasive blasting project is conducted, the Permittee shall log in indelible ink or in an electronic format, a record of the following:

a. The date the project was conducted;

b. The duration of the project; and

c. Type of control measures employed.
[A.A.C. R18-2-306.A.3.c] 3. Permit Shield

Compliance with the conditions of this Part shall be deemed compliance with
A.A.C. R18-2-726 and A.A.C. R18-2-702.B.
[A.A.C.R18-2-325]

B. Use of Paints

1

. Volatile Organic Compounds

a. Emission Limitations/Standards

While performing spray painting opera tions, the Permittee shall comply with the following requirements:

i. The Permittee shall not conduc t or cause to be conducted any spray painting operation without minimizing organic solvent emissions. Such operations, other than architectural coating and spot painting, shall be conducte d in an enclosed area equipped with controls containing no less than 96 percent of the overspray.
[A.A.C.R18-2-727.A]

ii. The Permittee or their designated contractor shall not either:

(1) Employ, apply, evaporate, or dry any architectural coating containing photochemically reactive solvents for industrial or commercial purposes; or

(2) Thin or dilute any architectural coating with a photochemically reactive solvent.
[A.A.C.R18-2-727.B]

iii. For the purposes of Condition XII.B.1.a.ii, a photochemically reactive solvent shall be any solv ent with an aggregate of more than 20 percent of its total volume composed of the chemical compounds classified in Conditions XII.B.1.a.iii.(1) through XII.B.1.a.iii(3) below, or which exceeds any of the following percentage composition limitations , referred to the total volume
of solvent:TV Renewal Permit No. 53399 Page 94 of 109 May 31, 2012 APS-Cholla Generating Station (1) A combination of the following types of compoundshaving an olefinic or cyclo-olefinic type of unsaturationhydrocarbons, alcohols, aldehydes, esters, ethers, or ketones: 5 percent.

(2) A combination of aromatic compounds with eight or more carbon atoms to the molecule except ethylbenzene: 8 percent.

(3) A combination of ethylbenzene, ketones having branched hydrocarbon structures, trichloroethylene or toluene: 20 percent.
[A.A.C.R18-2-727.C]

iv. Whenever any organic solvent or any constituent of an organic solvent may be classified from its chemical structure into more than one of the groups of organic compounds described in Conditions XII.B.1.a.iii.(1) thro ugh XII.B.1.a.iii(3) above, it shall be considered to be a member of the group having the least allowable percent of the total volume of solvents.
[A.A.C.R18-2-727.D]

b. Monitoring and Recordkeeping Requirements

i Each time a spray painting proj ect is conducted, the Permittee shall log in indelible ink, or in an electronic format, a record of the following:

(1) The date the project was conducted;

(2) The duration of the project;

(3) Type of control measures employed;

(4) Material Safety Data Sheet s for all paints and solvents used in the project; and

(5) The amount of paint consumed during the project.

ii. Architectural coating and spot painting projects shall be exempt from the recordkeeping requirements of Condition XII.B.1.b.i
above. [A.A.C. R18-2-306.A.3.c]

c. Permit Shield

Compliance with the conditions of this Part shall be deemed compliance
with A.A.C.R18-2-727. [A.A.C.R18-2-325]

2. Opacity

a. Emission Limitation/Standard

The Permittee shall not cause, allow or permit visible emissions from painting operations in excess of 20% opacity, as measured by EPA Reference Method 9. [ A.A.C. R18-2-702.B]TV Renewal Permit No. 53399 Page 95 of 109 May 31, 2012 APS-Cholla Generating Station b. Permit Shield

Compliance with the conditions of this Part shall be deemed compliance
with A.A.C. R18-2-702.B. [A.A.C. R18-2-325]

C. Demolition/Renovation - Hazardous Air Pollutants

1. Emission Limitation/Standard

The Permittee shall comply with all of the requirements of 40 CFR 61 Subpart M (National Emissions Standards for Haza rdous Air Pollutants - Asbestos).
[A.A.C. R18-2-1101.A.8]

2. Monitoring and Recordkeeping Requirement

The Permittee shall keep all required record s in a file. The required records shall
include the “NESHAP Notification fo r Renovation and Demolition Activities” form and all supporting documents. [A.A.C. R18-2-306.A.3.c]

3

. Permit Shield

Compliance with the conditions of this Part shall be deemed compliance with
A.A.C. R18-2-1101.A.8. [A.A.C. R18-2-325]

D. Solvent Degreasing

1. The Permittee shall process, store, use, and transport materials including solvents or volatile compounds in such a manner and by such means that they will not evaporate, leak, escape, or be otherwise discharged into the atmosphere so as to cause or contribute to air pollution. Where means are available to reduce effectively the contribution to air pollution from evaporation, leakage, or discharge, the installation and usage of such control methods, devices, or equipment shall be mandatory. [A.A.C. R18-2-730.F]

2. Permit Shield

Compliance with the conditions of this Part shall be deemed compliance with
A.A.C. R18-2-730.F. [A.A.C. R18-2-325]

E. Nonvehicle Air Conditioner Maintenance and/or Services

1. The Permittee shall comply with the applicable requirements of 40 CFR 82 - Subpart F (Protection of Stratospheric Ozone - Recycling and Emissions Reduction). [40 CFR 82, Subpart F]

2. The Permittee shall keep a record of a ll relevant paperwork to the applicable requirements of 40 CFR 82 - Subpart F on file. [A.A.C. R18-2-306.A.3.c]

3. Permit Shield

Compliance with the conditions of this Part shall be deemed compliance with
A.A.C. R18-2-1101.A.8. [A.A.C. R18-2-325]TV Renewal Permit No. 53399 Page 96 of 109 May 31, 2012 APS-Cholla Generating Station XIII. INTERNAL COMBUSTION ENGINES

A. Applicability

This Section applies to t he following inte rnal combustion engines as described in the equipment list in Attachment “C” of this permit.

B. Particulate Matter and Opacity

1. Emission Limits/Standards

a. The Permittee shall not cause or allow to be discharged into the

at mosphere from the internal co mbustion engines any smoke for any period greater than 10 consecutive seconds which exceeds 40% opacity. Visible emissions when starting cold equipment shall be exempt from this requirement for the first 10 minutes. [A.A.C. R18-2-719.E]

b. The Permittee shall not cause, allow or perm it the emission of particulate matter, caused by combustion of fu el, from the internal combustion engines having a heat input rate of 4200 million Btu per hour or less, in excess of the amounts calculated by the following equation:
[A.A.C. R18-2-719.C.1] E = 1.02Q 0.769

where:

E = the maximum allowable particul ate emissions rate in pounds-mass per hour

Q = the heat input in million BTU per hour.

c. For the purposes of Condition XIII.B.1.b above, the heat input shall be the aggregate heat content of all fuels whose products of co mbustion pass through a stack or other outlet. Compliance tests shall be conducted during operation at the normal rated capacity of each unit. The total heat input of all operation generators and internal combustion engines on a plant or premises shall be used for determining the maximum allowable amount of particulate matter which may be emitted.
[A.A.C. R18-2-719.B] 2. Monitoring, Recordkeeping and Reporting Requirements

The Perm ittee shall conduct a weekly Visible Emissions Observation Procedure consistent with Condition I.H of this Attachment, for any visible emissions emanating from all internal combustion engines subject to this Section.
[A.A.C. R18-2-306.A.3.c] C. Sulfur Dioxide

1. Emission Limits/Standards

a. The Permittee shall only burn low sulfur fuel oil in the internal combustion engines located at the facility. Low sulfur oil is defined as fuel oil containing less than 0. 90% by weight of sulfur.
[A.A.C.R18-2-719.H]

b. The Permittee shall not emit or cause to be em itted into the atmosphere any gases containing sulfur dioxide in excess of 1.0 pound per millionTV Renewal Permit No. 53399 Page 97 of 109 May 31, 2012 APS-Cholla Generating Station Btu heat input when low sulfur fuel oil is fired. [A.A.C.R18-2-719.F]

2. Monitoring, Recordkeeping and Reporting Requirements

a. The Permittee shall maintain record s o f the lower heating value of the fuel fired in the internal combustion engines. This may be accomplished by maintaining on record a copy of fuel supplier certifications that specify the lower heating value of the fuel. [A.A.C. R18-2-306.A.3.c and A.A.C. R18-2-719.I]

b. The Permittee shall report to the Director any daily period during which
the sulfur content of the fue l bei ng fired in the machine exceeds 0.8%. [A.A.C. R18-2-719.J and 306.A.3] D. Permit Shield

Compliance with the conditions of this Secti on shall be deem ed compliance with A.A.C. R18-2-719.B, A.A.C. R18-2-719.C.1, A.A.C. R18-2-719.E, A.A.C. R18-2-719.F, A.A.C. R18-2-719.H, A.A.C. R18-2-719.I, and A.A.C. R18-2-719.J. [A.A.C. R18-2-325]

XIV. MERCURY REQUIREMENTS

A. Applicability

1. The requirements in this section are state enforceable only. [Consent Order #A-19-09]

2

. The State Standards of Performance for Mercury Emissions from Coal-Fired Electric Steam Generating Units set forth in A.A.C. R18-2-734 shall not be enforceable until December 31, 2016.

B. Operation and Maintenance (O&M) Plan

The Permittee shall implement the followi ng Operation and Maintenance (O&M) plan, designed to achieve a minimum of 50 percen t reduction of total inlet mercury where “inlet mercury” means the average concentrati on of mercury in coal burned at the facility, as determined by ASTM methods, EPA appr oved methods or an alternative method approved by the Director.

1. The PM emissions CAM plan outlined in Attachment “E” of Permit No. 53399 shall serve as the operation and maintenance plan for the fabric filters for reduction of mercury emissions from Units 1, 3 and 4, and from Unit 2 after installation of the fabric filter system.

2. The Permittee shall annually inspect and maintain the fabric filter control devices in accordance with manufacturer’s specifications.

3. The Permittee shall operate and maintain at all times the lime s lurry flue gas desulfurization system on Units 1, 3 and 4, and on Unit 2 after the FGD is operational in a manner consistent with good air pollution control practice for minimizing mercury emissions

. [A.A.C. R18-2-306.A.3.c and -331.A.3.e] [Material permit conditions are indicated by underline and italics]

C. Monitoring, Recordkeeping, and Reporting Requirements [A.A.C. R18-2-306.A.3.c]

1. The Permittee shall analyze a representative sample from each train load of coalTV Renewal Permit No. 53399 Page 98 of 109 May 31, 2012 APS-Cholla Generating Station delivered to the facility, and shall calculate average monthly mercury concentration in coal in parts per billi on (ppb). Based on this analysis and the total amount of coal fired in Units 1, 2, 3 and 4, the Permittee shall determine pounds of inlet mercury for each unit every month (“Hg in”).

2. The Permittee shall install, calibrate , operate and maintain continuous emission monitoring system (CEMS) for mercury on Unit 4 in accordance with vendor specifications. [A.A.C. R18-2-306.A.3.c and -331.A.3.c] [Material perm it conditions are indicated by underline and italics]

3. The Permittee shall determine the merc ury emissions in the exhaust of Unit 4
boiler in pounds per GWHr, using the comp liance-certified CEMS DAHS. The data shall be averaged on a monthly basis and recorded. Based on this analysis and monthly gross megawatt output recorded by the CEMS for each Unit, the Permittee shall determine poun ds of mercury in exhaust for Units 1, 3 and 4 every month and every month on Unit 2 afte r the fabric filter is operational (“Hg out”).

4. As an option to the mercury CEMS, the Permittee may install and maintain a mercury sorbent trap system in the Unit 4 stack in accordance with vendor specifications. If a mercury sorbent trap system is used, the Permittee shall meet all of the following:

a. Sample the stack gas at a rate proportional to the stack gas volumetric flow rate. The Permittee shall by using the sample volume measured by the gas meter and the results of th e analyses of the sorbent traps, determine the average mercury concentr ation in the stack in micrograms per dry standard cubic meter.

b. Analyze the sorbent traps on-site or at a qualified off-site laboratory using a desorption analyzer. When an appropriate protocol is provided by US EPA, the Permittee shall calibrate the analyzer by using National
Institute of Standards and Tec hnology (NIST) traceable mercury
standards.

c. On monthly basis, the Permittee shall determine the pounds of mercury in the exhaust of Units 1, 3, and 4, and in the exhaust of the Unit 2 after the fabric filter system becomes operational.

5. At the end of each calendar year, the Permittee shall calculate and record the average calendar year mercury removal percentage based on the results of
Conditions XIV.C.1 and XIV.C.3. Until such time that a fabric filter system is operational on Unit 2, mercury removal fo r Unit 2 shall be considered as zero.

Annual mercury removal efficiency

= ( Σ “Hg in ” for Units 1, 3, 4 – Σ “Hg out” for Units 1, 3, 4) * 100

Σ “Hg in” for Units 1- 4

D. Significant Permit Revision Application Submittal

The Permittee shall submit an application for a significant permit revision required by A.A.C. R18-2-734(F) by no later than January 1, 2014. The application shall include the following elements: [Consent Order #A-19-09]TV Renewal Permit No. 53399 Page 99 of 109 May 31, 2012 APS-Cholla Generating Station 1. The State Mercury Standard and any amendments adopted by ADEQ to ensure that the State Mercury Standard is not incompatible with a MACT standard promulgated by EPA.

2. A control strategy for meeting the State Mercury Standard and any amendments adopted by ADEQ to ensure that the Stat e Mercury Standard is not incompatible with a MACT standard promulgated by EPA.

3. A demonstration that the control strategy is designed to meet the State Mercury Standard and any amendments adopted by ADEQ to ensure that the State Mercury Standard is not incompatible with a MACT standard promulgated by

EPA.

4. A proposal to comply with the State Mercury Standard by December 31, 2016, except as provided in A.A.C. R18-2-734(H), under the following conditions;

(a) For the purposes of applying the exception established in A.A.C. R18-2- 734(H), each date specified in that pr ovision shall be increased by three calendar years.

(b) The exception in A.A.C. R18-2-734(G) shall not apply.

### ATTACHMENT “C”: EQUIPMENT LIST

AIR QUALITY CONTROL PERMIT NO. 53399

FOR

ARIZONA PUBLIC SERVICE COMPANY–C HOLLA GENERATING STATION

Table C-1: Equipment List

Equipment Operating
Scenario Quantity Manufacturer Model/ Type Serial
Number Date
Installed Rated Capacity

UNIT 1
Boiler - Tangential fired
furnace Normal 1 Combustion Engineering R 19537 1961 865K lbs/hr steam flow @1925 psig @1005 degrees F at superheater outlet

Coal Mills - bowl
mills Normal 4 Combustion Engineering #633 60814 through
60817 1961 34,000 lbs/hr coal each

Absorber – Lime slurry Normal 2 URS Tray

Tower 2007 240,000 acfm each with combined
90% SO 2 removal

Fabric Filter Normal 1 Alstom Puls e Jet 2007 99.9% design efficiency

UNIT 2
Boiler - Tangential fired
furnace Normal 1 Combustion Engineering RR 7072 1974 2,015K lbs/hr steam @1990 psig @1005 degrees F at superheater
outlet

Coal Mills - bowl
mills Normal 5 Combustion Engineering #863 72806 through

72810 1974 94,400 lbs/hr coal each

Scrubber/Absorbe

r Normal 4 wet
Venturi
scrubber
modules

and 4
absorber

towers Research Cottrell
-- -- 1974 413,500 acfm each with combined
90% SO 2 and 98% PM removal.

Mechanical dust
collector Normal 1 Zurn
-- -- 1974 Approx. 70% efficiency @ 248,000- 332,000 lbs/hr gas flow. Emergency
Diesel Generator Normal 1 Beloit Power Systems -- 604588-

R1 1974 750 KW @ 480 volts

UNIT 3
Boiler - Tangential fired
furnace Normal 1 Combustion Engineering RR 9272 1975 2,015K lbs/hr steam @1990 psig @1005 degrees F at superheater
outlet

Coal Mills - bowl
mills Normal 5 Combustion Engineering #863 74817 through
74821 1975 94,400 lbs/hr coal each

Absorber – Lime slurry Normal 1 BPE1 Tray

Tower 2009 0.15 lbs/MMBtu design outlet
emissions rate

Fabric Filter Normal 1 Hamon Research
Cottrell Pulse Jet 2009 99.9% design efficiency

Emergency
Diesel Generator Normal 1 Beloit Power Systems -- 504588-

R2 1975 750 KW @ 480 volts

Cooling tower Normal 1 Marley 6516-3-6
forced
draft-7

cells -- 1975 140,000 gpm water flow

UNIT 4
Boiler - Tangential fired
furnace Normal 1 Combustion Engineering RR 5174 1978 2,830K lbs/hr steam @1990 psig @1005 degrees F at superheater
outlet

Coal Mills - bowl
mills Normal 5 Combustion Engineering #903 74840 through
74844 1978 108,000 lbs/hr coal each

TV Renewal Permit No. 53399 Page 100 of 109 March 28, 2012 APS – Cholla Generating StationAPS – Cholla Generating Station Equipment Operating
Scenario Quantity Manufacturer Model/ Type Serial
Number Date
Installed Rated Capacity

Absorber – Lime slurry Normal 1 BPE1 Tray

Tower 2008 0.15 lbs/MMBtu design outlet
emissions rate

Fabric Filter Normal 1 Hamon Research
Cottrell Pulse Jet 2008 99.9% design efficiency

Emergency
Diesel Generator Normal 1 Beloit Power Systems -- 504637-

R1 1978 900 KW @ 480 volts

Cooling tower Normal 1 Marley 6516-3-6
Forced
draft 11

cells -- 1978 145,000 gpm water flow

FLY ASH HANDLING SYSTEM

Fly ash Baghouse Normal 2 GE GE-154-
6-12P -- 1988 100% capacity pulse-jet baghouse, 154 bags per baghouse, 6"x12' bags

LIME SLAKING SYSTEM
Old & New Lime

Silo Baghouse Normal 1 Flex-Kleen 58 BVBS
25IIG W33793 1994 25 bags, pulse jet baghouse, 6"x6' bags

Old & New Lime
Slaker Vent Wet
Scrubber Normal 1 Ducon UW-4 IV
size 30 -- 1994 2500 inlet acfm @200 degree F

COAL WETTING SYSTEM
Coal Dust Suppression

System Normal 1 Nalco Nalco #
-- 1995 Chemical treatment and/or wetting
at each crusher and various transfer points as needed.

COAL HANDLING SYSTEM- NEW TRACK (New Source Performance Standards – Subpart Y Applicable)

NU1 – Rail Car Discharge Point Normal 1 Continental Conveyor -- -- 1974
Retrofitte
d in 2008 2,200

NU2 – Conveyor

12A Discharge Normal 1 Continental Conveyor -- -- 1974
Retrofitte
d in 2008 2,200

NU3 – Conveyor

12B Discharge Normal 1 Continental Conveyor -- -- 1974
Retrofitte
d in 2008 2,200

NU4 - Crusher

Tower #2 Discharge To Conveyor 32
North/South Normal 1 Continental Conveyor -- -- 1974
Retrofitte
d in 2008 2,200

NU5 – Crusher

Tower #2 Discharge To Conveyor 35 Normal 1 Continental Conveyor -- -- 1974 560

NU6 – Conveyor
32 North/South

Discharge Normal 1 Continental Conveyor -- -- 1974
Retrofitte
d in 2008 2,200

NU7- Transfer

Tower #3 Discharge To Conveyor 22 Normal 1 Continental Conveyor -- -- 1974 1,800

NU8 – Transfer
Tower #3 Discharge To Conveyor 33

East/West Normal 1 Continental Conveyor -- -- 1974 1,800

NU9 – Conveyor 22 Discharge to

Storage Pile Normal 1 Continental Conveyor -- -- 1974 1,800

COAL UNLOADING SYSTEM – OLD T RACK –(A.A.C. Rules Applicable)

TV Renewal Permit No. 53399 Page 101 of 109 March 28, 2012APS – Cholla Generating Station Equipment Operating
Scenario Quantity Manufacturer Model/ Type Serial
Number Date
Installed Rated Capacity

O1 – Old Track

Unloading

Hopper Inlet/Discharge Normal 2 Continental Conveyor -- -- 1961 560

O2 – Conveyor 11 Discharge To
Crusher Tower #1 Normal 1 Continental Conveyor -- -- 1961 560

O3- Conveyor 11

Discharge To Conveyor 21 Normal 1 Continental Conveyor -- -- 1961 560

O4 – Crusher

Tower #1 Discharge To Conveyor 31 Normal 1 Continental Conveyor -- -- 1961 560

O5 – Crusher

Tower #1 Discharge To Conveyor 35 Normal 1 Continental Conveyor -- -- 1961 560

O6 – Conveyor 21 Discharge to

Storage Pile Normal 1 Continental Conveyor -- -- 1961 560

COAL RECLAIM SYSTEM
RC1 – Reclaim Hopper Discharge Normal 1 Continental Conveyor -- -- 1974 1,800

RC2 – Conveyor 24 (E&W) Discharge To Conveyor 25

(E&W) Normal 1 Continental Conveyor -- -- 1974 1,800

R3 – Conveyor

25 (E&W) Discharge To
Crusher Tower #2 Normal 1 Continental Conveyor -- -- 1974 1,800

R4 – Crusher

Tower #2 Discharge To Conveyor 35 Normal 1 Continental Conveyor -- -- 1974 560

RC5 – Crusher

Tower #2 Discharge To Conveyor 32
North/South Normal 1 Continental Conveyor -- -- 1974 1,800

RC6 – Conveyor
32 North/South Discharge To
Transfer Tower
#3 Normal 1 Continental Conveyor -- -- 1974 1,800

RC7 – Transfer
Tower #3 Discharge To Conveyor 33

East/West Normal 1 Continental Conveyor -- -- 1974 1,800

COAL SILO FEED SYSTEM CF1 – Conveyor

31 Discharge Normal 1 Continental Conveyor -- -- 1961 560

CF2 – Conveyor

41 (A or B) Discharge Normal 1 Continental Conveyor -- -- 1974 560

CF4 – Conveyor

33 East/West Discharge To Conveyor 34 Normal 1 Continental Conveyor -- -- 1974 1,800

TV Renewal Permit No. 53399 Page 102 of 109 March 28, 2012APS – Cholla Generating Station Equipment Operating
Scenario Quantity Manufacturer Model/ Type Serial
Number Date
Installed Rated Capacity

North/South CF5 – Conveyor
34 North/South Discharge To Conveyor 42 (A&B) Normal 1 Continental Conveyor -- -- 1974 1,800

CF6 – Conveyor
34 North/South Discharge To Conveyor 43 (A&B) Normal 1 Continental Conveyor -- -- 1975 1,800

CF7 – Conveyor
34 North/South Discharge To Conveyor 36 (North & South) Normal 1 Continental Conveyor -- -- 1978 1,800

CF8 – Conveyor

36 (North & South) Discharge to Conveyor 44 (A&B) Normal 1 Continental Conveyor -- -- 1978 1,800

Dust Collector

(Unit 1 Silo
Ventilation & Conveyors, Tag

no. DC-01A) Normal 1 MAC Equipment 144MCF1 53-145, Style III 36307-
001-1 2002 Exhaust Fan Volumetric Flow Rate: 12,350 cfm; Static Pressure: 13.00” wg

Dust Collector

(Unit 2 Silo Ventilation, Tag

no. DC-02A) Normal 1 MAC Equipment 144MCF2 55-165, Style III 36307-
031-1 2002 Exhaust Fan Volumetric Flow Rate: 14,000 cfm; Static Pressure: 13.00” wg

Dust Collector (Unit 2 Transfer Conveyors, Tag

no. DC-02B) Normal 1 MAC Equipment 144MCF3 61-85, Style III 36307-
051-1 2002 Exhaust Fan Volumetric Flow Rate: 24,000 cfm; Static Pressure: 14.00” wg

Dust Collector

(Unit 3 Silo Ventilation, Tag

no. DC-03A) Normal 1 MAC Equipment 144MCF1 53-145, Style III 36307-
011-1 2002 Exhaust Fan Volumetric Flow Rate: 14,000 cfm; Static Pressure: 13.00” wg

Dust Collector (Unit 3 Transfer Conveyors, Tag

no. DC-03B) Normal 1 MAC Equipment 144MCF2 55-165, Style III 36307-
041-1 2002 Exhaust Fan Volumetric Flow Rate: 12,000 cfm; Static Pressure: 14.00” wg

Dust Collector

(Unit 4 Silo Ventilation, Tag

no. DC-04A) Normal 1 MAC Equipment 144MCF1 53-130, Style III 36307-
061-1 2002 Exhaust Fan Volumetric Flow Rate: 11,000 cfm; Static Pressure: 11.00” wg

Dust Collector (Unit 4 Transfer Conveyors, Tag

no. DC-04B) Normal 1 MAC Equipment 144MCF1 53-145, Style III 36307-
021-1 2002 Exhaust Fan Volumetric Flow Rate: 12,000 cfm; Static Pressure: 13.00” wg

Crusher Tower
Dust Collector Normal 1 MAC Equipment 144MCF4 94-430, Style III 118043-
001-1 2008 Exhaust Fan Volumetric Flow Rate: 36,450 cfm; Static Pressure: 13.00” wg

Transfer Tower
Dust Collector Normal 1 MAC Equipment 144MCF2 55-200, Style III 118043-
003-1 2008 Exhaust Fan Volumetric Flow Rate: 17,600 cfm; Static Pressure: 13.00” wg

TV Renewal Permit No. 53399 Page 103 of 109 March 28, 2012TV Renewal Permit No. 53399 Page 104 of 109 March 28, 2012 APS – Cholla Generating Station Table C-2: Stack Parameters

Identification Stack 1 Stack 2 Stack 3 Stack 4

Description Round Vertical Stack Round Vertical Stack Round Vertical
Stack Round Vertical
Stack Building Dimensions (boiler structure) 50 ft W100 ft L155 ft

H 100 ft W100 ft L217
ft H 100 ft W100 ft
L217 ft H 120 ft W100 ft
L247 ft H

Height 250 ft 550 ft 550 ft 550 ft

Inside Dimensions 11.25 ft 14.67 ft 17.15 ft 19.17 ft

Exit Gas Temperature 123 oF 170.8 oF 127 oF 127 oF

Exit Gas Velocity 48.74 ft/sec 68.0 ft/sec 63.23 ft/sec 74.59 ft/sec

Table C-3: Continuous Emission Monitors

Steam Unit NOx
Monitor SO 2 Monitor CO 2 Monitor Opacity Monitor Flow Monitor CO

Inlet: TML50 Inlet:TML20

Steam Unit 1 TML 41 Outlet: TML50 Outlet: TML20 TML Lighthawk

560 TML Ultraflow

150 TML
30U

Inlet: TML50 Inlet:TML20 Steam Unit 2 TML 41 Outlet: TML50 Outlet: TML20 Monitor Labs

550M TML Ultraflow

150 TML
30U

Steam Unit 3 TML 41 TML50 TML20 TML Lighthawk

560 TML Ultraflow

150 TML
30U

Steam Unit 4 TML 41 TML50 TML20 TML Lighthawk

560 TML Ultraflow

150 TML
30UTitle V Renewal Permit # 53399 Page 105 of 109 May 31, 2012 APS Cholla Generating Station 

### ATTACHMENT "D": PHASE II ACID RAIN PROVISIONS

AIR QUALITY CONTROL PERMIT NO. 53399

FOR

ARIZONA PUBLIC SERVICE COMPANY–C HOLLA GENERATING STATION

I. STATEMENT OF BASIS

Statutory and Regulatory Authorities: In accordance with Arizona Revised Statutes, Title 49, Chapter 3, Article 2, Section 426.N, and Titles IV and V of the Clean Air Act, the Arizona Department of Environmental Quality issues this Phase II Acid Rain Permit pursuant to Arizona Administrative Code, Title 18, Chapter 2, Article 3, Section 333 ( A.A.C. R18-2-333), “Acid Rain”.

II. SO 2 ALLOWANCE † ALLOCATIONS AND NOx REQUIREMENTS FOR EACH AFFECTED UNIT

Units 2012 2013 2014 2015 2016 2017 2018

Unit 1 2,034 2,034 2,034 2,034 2,034 2,034 2,034

Unit 2 5,067 5,067 5,067 5,067 5,067 5,067 5,067

Unit 3 4,858 4,858 4,858 4,858 4,858 4,858 4,858 SO 2 allowances under Tables 2, 3, or 4 of 40 CFR part 73

Unit 4 7,784 7,784 7,784 7,784 7,784 7,784 7,784

NO

x Emission Limit For each boiler Unit, NO

x emission rate for each year, determined in accordance with 40 CFR Part 75, shall not exceed the applicable emission limitation, under 40 CFR 76.7(a)(1) of 0.40 lb/MMBtu for tangentially fired boilers.

† As defined in 40 CFR §72.2, “Allo wance” means an authorization by the Administrator under the Acid Rain Program to emit up to one ton of sulfur dioxide during or after a specified calendar year.

III. COMMENTS, NOTES AND JUSTIFICATIONS

APS has earl y-elected for NO

x requirements on Units 1 through 4.

IV. PERMIT APPLICATION

The Perm ittee, and any other owners or operators of the units at this facility, shall comply with the requirements contained in the attached acid rain pe rmit application (OMB No. 2060-0258) signed by Mr. James Riley on March 17, 2011.Title V Renewal Permit # 53399 Page 106 of 109 May 31, 2012 APS Cholla Generating Station 

### ATTACHMENT "E": COMPLIANCE ASSURANCE MONITORING

AIR QUALITY CONTROL PERMIT NO. 53399

FOR

ARIZONA PUBLIC SERVICE COMPANY–C HOLLA GENERATING STATION

I. APPLICABILITY

The com pliance assurance monitoring (CAM) required unde r this attachment shall apply to Steam Boiler Units 1 through 4 for particulate matter emissions.

II. CAM PLAN

A. Steam Boiler Units

1. Applicability

The CAM plan is applicable to Unit 1, 3, and 4 boilers and for Unit 2 boiler, upon the installation and operation of fabric filter control system.

2. Indicator

The opacity of exhaust gases shall be an indicator of particulate matter emissions. [40 CFR 64.6(c)(1)(i)]

3. Monitoring Approach [40 CFR 64.6(c)(1)(i) and (ii)]

a. The COMS installed on outlet duct work of the fabric filter baghouses serving the boiler units shall be used to monitor opacity for each stack.

: b. Using COMS data, the Permittee shall calculate block 1-hour average opacities comprised of individual six minute averages excluding periods of boiler startup and
shutdown.

4. Excursion Determination

Block 1-hour average opacities of 8% or greater shall be considered an excursion. For any such excursion event, the Permittee shall initiate a mandatory investigation within 30 minutes, including inspection of the clean side of each in-service baghouse compartment for signs of dusting. If dusting is observed maintenance activities should be performed expeditiously. The Permittee shall keep record s of the investigation conducted with details of any corrective action taken. [40 CFR 64.6(c)(2)]

B. Steam Boiler Unit 2

1. Applicability

The section is applicable to Unit 2 until the fabric filter system is operational.

2. Primary Indicators

Until such time that the fabric filter system is operational on Unit 2, the flooded discTitle V Renewal Permit # 53399 Page 107 of 109 May 31, 2012 APS Cholla Generating Station pressure drop ( Δ p) and slurry flow shall be primar y indicators of Unit 2 Venturi scrubbers’ performance. [40 CFR 64.6(c)(1)(i)]

2. Monitoring Approach [40 CFR 64.6(c)(1)(i) and (ii)]

a. The Permittee shall measure the flooded disc Δ p an d slurry flow and collect four or more data points each hour.

b. The measurement instruments in use for Δ p and sl urry flow shall be calibrated, maintained, and operated using procedures that take into account manufacturer’s
recommendations.

3. Excursion Determination [40 CFR 64.6(c)(2)]

a. Using the flooded disc Δ p and slurry flow data, the Permittee shall calculate block 1-
hour Δ p and slurry flow average excluding periods of boiler startup and shutdown.

b. If at any point, excluding periods of bo iler startup and shutdown, the block 1-hour
Δ p average is less than 15 inches of water column or the block 1-hour slurry flow average is equal to or less than 4,0 00 gallons per minute per pump, then an
excursion has occurred and shall be recorded and reported accordingly.

c. The Permittee shall also record the opera tional status of Unit 2 boiler (i.e. load change increase or decrease) in conjunc tion with the excursion recordation.

III. CAM OPERATION REQUIREMENTS [40 CFR 64.7]

A

. Upon issuance of the permit, the Permittee shall conduct the monitoring for each affected control device in accordance with the CAM plan outlined in Section II of this attachment.

E. At all times, the Permittee shall maintain the monitoring, including but not limited to, maintaining

necess ary parts for routine repairs of the monitoring equipment.

F. Except for, as applicable, monitoring malfunctions, associated rep airs, and required quality assurance or control activities (including, as applicable, calibration checks and required zero and span adjustments), the Permittee shall conduct all monitori ng in continuous operation (or shall collect data at all required intervals) at all times that the pollutant-specific emissions unit is operating. Data recorded during monitoring malfunctions, associat ed repairs, and required quality assurance or control activities shall not be used for purposes of this Section, including data averages and calculations, or fulfilling a minimum data availability requirement, if applicable. The Permittee shall use all the data collected during all other periods in assessing the operation of the control device and associated control system. A monitoring malfunction is any sudden, infrequent, not reasonably preventable failure of the monitoring to provide vali d data. Monitoring failures that are caused in part by poor maintenance or careless operation are not malfunctions.

G. Upon detecting an excursion or exceedance, the Pe rmittee shall r estore operation of the pollutantspecific emissions unit (including the control device and associated capture system) to its normal or usual manner of operation as e xpeditiously as practicable in accordance with good air pollution control practices for minimizing emissions. The r esponse shall include minimizing the period of any startup, shutdown or malfunction and taking any necessary corrective actions to restore normal operation and prevent the likely recurrence of the ca use of an excursion or exceedance (other than those caused by excused startup or shutdown co nditions). Such actions may include initialTitle V Renewal Permit # 53399 Page 108 of 109 May 31, 2012 APS Cholla Generating Station inspection and evaluation, recording that operations returned to normal without operator action (such as through response by a computerized distributio n control system), or any necessary follow-up actions to return operation to within the i ndicator range, designated condition, or below the applicable emission limitation or standard, as applicable.

H. Determination of whether the Permittee has used acc eptable procedures in response to an excursion
or exceedance will be based on information availabl e, which may include but is not limited to, monitoring results, review of operation and mainte nance procedures and records, and inspection of the control device, associated cap ture system, and the process.

I. If the Permittee identifies a failure to achieve complia nce with an emission limitation or standard for which the approved monitoring did not provide an indica tion of an excursion or exceedance while providing valid data, or the results of compliance or performance testing document a need to modify the existing indicator ranges or designated cond itions, the Permittee shall promptly notify the Director and, if necessary, submit a proposed modification to the permit to address the necessary monitoring changes. Such a modification may includ e, but is not limited to, reestablishing indicator ranges or designated conditions, modifying the fre quency of conducting monitoring and collecting data, or the monitoring of additional parameters.

IV. QUALITY IMPROVEMENT PLAN (QIP) REQUIREMENTS [40 CFR 64.8]

A

. In the event that an accumulation of exceedanc es or excursions exceeds 5 percent duration of a pollutant-specific emissions unit's operating time for a reporting period based on the results of a
determination made under Condition III.E above, the Permittee sha ll develop and implement a QIP. The Director may otherwise specify the threshold at a higher or lower percent or rely on other criteria for purposes of indicating whether a pollutant -specific emissions unit is being maintained and operated in a manner consistent with good air pollution control practices.

B. The QIP shall include the following elements:

1. The Permittee shall maintain a written QIP, if re quired, and have it a vailable for inspection.

2. The plan initially shall incl ude procedur es for evaluating the control performance problems and, based on the results of the evaluation pro cedures, the Permittee shall modify the plan to include procedures for conducting one or more of the following actions, as appropriate:

a. Improved preventive maintenance practices;

b. Process operation changes;

c. Appropriate improvement s to control methods;

d. Other steps appropriate to correct control performance;

e. More frequent or improved monitoring (only in con junction with one or more steps a through d).

C. If a QIP is required, the Permittee shall develop and implement a QIP as expeditiously as practicable and shall notify the Director if the period for completing the improvements contained in the QIP exceeds 180 days from the date on which the n eed to implement the QIP was determined.

D. Following implementation of a QIP, upon any sub sequent determination pur suant to Condition III.E above, the Director may require that the Permittee make reasonable changes to the QIP if the QIP is
found to have:Title V Renewal Permit # 53399 Page 109 of 109 May 31, 2012 APS Cholla Generating Station 1. Failed to address the cause of the control device performance proble ms; or

2. Failed to provide adequate procedures for co rrecting control devic e performance problems as expeditiously as practicable in accordance w ith good air pollution control practices for minimizing emissions.

E. Implementation of a QIP shall not excuse the Pe rmittee from compliance with any existing emission limitation or standard, or any existing monitoring, testing, reporting or recordkeeping requirement that may apply under federal, state, or local law, or any other applicable requirements under the Act.

V. REPORTING AND RECORDKEEPING REQUIREMENTS [40 CFR 64.9]

A. Upon issuance of the permit, the Permittee sha ll submit monitoring reports pertaining to this attachment to the Director along with Condition I.H, Attachment “B” and in accordance with Section XII, Attachment “A” of the permit.

B. A report for monitoring under this attachment sha ll include, at a minimum, the information required under Condition I.H, Attachment “B” and Section XII, Attachment “A” of the permit, and the following information, as applicable:

1. Summary information on the number, duration and cause (including unknown cause, if applicable) of excursions or exceedance s, as applicable, and the corrective actions taken;

2. Summary information on the number, duration and cause (including unknown cause, if applicable) for m onitor downtime incidents (o ther than downtime associated with zero and span or other daily calibration checks, if applicable); and

3. A description of the actions taken to im ple ment a QIP during the reporting period as specified in Section IV above. Upon completion of a QIP, the Permittee shall include in the next summary report documentation that the impl ementation of the plan has been completed
and reduced the likelihood of similar leve ls of excursions or exceedances occurring.

4. The Permittee shall comply with the recordk eeping requirements specified in Section XIII, Attachment “A” of the permit. The Permittee shall maintain records of monitoring data, monitor performance data, corrective actions taken, any written quality improvement plan required pursuant to Section IV above and an y activities undertaken to implement a quality improvement plan, and other supporting informa tion required to be maintained under this section (such as data used to document the adequ acy of monitoring, or records of monitoring maintenance or corrective actions).

5. Instead of paper records, the Permittee may m aintain records on alternative media, such as microfilm, computer files, magnetic tape disks, or microfiche, provided that the use of such alternative media allows for expeditious insp ection and review, and does not conflict with other applicable recordkeeping requirements.

VI. PERMIT SHIELD [A.A.C. R18-2-325]

Compliance with the terms of this attachment shall be deemed compliance with 40 CFR Part 64.