DAQ-2024-008334

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DAQC-554-24
Site ID 10327 (B1)

MEMORANDUM

TO: FILE – INTERMOUNTAIN POWER SERVICE CORPORATION (IPP)

THROUGH: Harold Burge, Major Source Compliance Section Manager

FROM: Jeremiah Marsigli, Environmental Scientist

DATE: June 5, 2024

SUBJECT: FULL COMPLIANCE EVALUATION, Major, Millard County,
FRS ID# 0000004902700010

INSPECTION DATE: May 15, 2024

SOURCE LOCATION: 850 West Brush Wellman Road,
Delta, UT 84624-9546

SOURCE CONTACT(S): Mike Utley, Environmental Engineer [phone]
Mike Ferrell, Lead Environmental Technician [phone]

OPERATING STATUS: Unit #2 operating

PROCESS DESCRIPTION: Intermountain Power Service Corporation (IPP) operates the
Intermountain Generating Station (IGS) coal fired steam-electric
plant, consisting of two 450 MW units and ancillary facilities
located near Delta in Millard County.

Bituminous, sub-bituminous coals, and synfuel are used. The
fireball in the boiler heats water to steam. The steam is used to
turn turbines. The turbines are connected to an electric generator
that converts the energy to electricity. Gases from the coal
combustion exit the boiler to the baghouse for particulate
removal, go through the scrubber for SO2 removal, then exit the
stack. Steam is recycled and condensed to water as part of each
cycle.

APPLICABLE
REGULATIONS: Title V Operating Permit #2700010006, last revised
November 21, 2023

SOURCE INSPECTION
EVALUATION:

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SECTION I: GENERAL PROVISIONS

I.A Federal Enforcement.

All terms and conditions in this permit, including those provisions designed to limit the
potential to emit, are enforceable by the EPA and citizens under the Clean Air Act of 1990
(CAA) except those terms and conditions that are specifically designated as "State
Requirements." (R307-415-6b)

Status: This is not an inspection item.

I.B Permitted Activity(ies).

Except as provided in R307-415-7b(1), the permittee may not operate except in compliance
with this permit. (See also Provision I.E, Application Shield)

Status: In Compliance. The source appeared to be operating in compliance with the conditions of this
permit. See each condition below for more specific details.

I.C Duty to Comply.

I.C.1 The permittee must comply with all conditions of the operating permit. Any permit
noncompliance constitutes a violation of the Air Conservation Act and is grounds for any of
the following: enforcement action; permit termination; revocation and reissuance;
modification; or denial of a permit renewal application. (R307-415-6a(6)(a))

I.C.2 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. (R307-415-6a(6)(b))

I.C.3 The permittee shall furnish to the Director, within a reasonable time, any information that
the Director may request in writing to determine whether cause exists for modifying,
revoking and reissuing, or terminating this permit or to determine compliance with this
permit. Upon request, the permittee shall also furnish to the Director copies of records
required to be kept by this permit or, for information claimed to be confidential, the
permittee may furnish such records directly to the EPA along with a claim of
confidentiality. (R307-415-6a(6)(e))

I.C.4 This permit may be modified, revoked, reopened, and reissued, or terminated for cause.
The filing of a request by the permittee for a permit modification, revocation and
reissuance, or termination, or of a notification of planned changes or anticipated
noncompliance shall not stay any permit condition, except as provided under
R307-415-7f(1) for minor permit modifications. (R307-415-6a(6)(c))

Status: In Compliance. The source appeared to be operating in compliance with the conditions of this
permit. See each condition below for more specific details.

I.D Permit Expiration and Renewal.

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I.D.1 This permit is issued for a fixed term of five years and expires on the date shown under
"Enforceable Dates and Timelines" at the front of this permit. (R307-415-6a(2))

I.D.2 Application for renewal of this permit is due on or before the date shown under
"Enforceable Dates and Timelines" at the front of this permit. An application may be
submitted early for any reason. (R307-415-5a(1)(c))

I.D.3 An application for renewal submitted after the due date listed in I.D.2 above shall be
accepted for processing, but shall not be considered a timely application and shall not
relieve the permittee of any enforcement actions resulting from submitting a late
application. (R307-415-5a(5))

I.D.4 Permit expiration terminates the permittee's right to operate unless a timely and complete
renewal application is submitted consistent with R307-415-7b (see also Provision I.E,
Application Shield) and R307-415-5a(1)(c) (see also Provision I.D.2). (R307-415-7c(2))

Status: This permit has not expired.

I.E Application Shield.

If the permittee submits a timely and complete application for renewal, the permittee's
failure to have an operating permit will not be a violation of R307-415, until the Director
takes final action on the permit renewal application. In such case, the terms and conditions
of this permit shall remain in force until permit renewal or denial. This protection shall
cease to apply if, subsequent to the completeness determination required pursuant to
R307-415-7a(3), and as required by R307-415-5a(2), the applicant fails to submit by the
deadline specified in writing by the Director any additional information identified as being
needed to process the application. (R307-415-7b(2))

Status: This permit has not expired. Application for renewal is due by May 21, 2028.

I.F Severability.

In the event of a challenge to any portion of this permit, or if any portion of this permit is
held invalid, the remaining permit conditions remain valid and in force. (R307-415-6a(5))

Status: This is not an inspection item.

I.G Permit Fee.

I.G.1 The permittee shall pay an annual emission fee to the Director consistent with R307-415-9.
(R307-415-6a(7))

I.G.2 The emission fee shall be due on October 1 of each calendar year or 45 days after the source
receives notice of the amount of the fee, whichever is later. (R307-415-9(4)(a))

Status: In Compliance. Permit fees have been paid as invoiced.

I.H No Property Rights.

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This permit does not convey any property rights of any sort, or any exclusive privilege.
(R307-415-6a(6)(d))

Status: This is not an inspection item.

I.I Revision Exception.

No permit revision shall be required, under any approved economic incentives, marketable
permits, emissions trading and other similar programs or processes for changes that are
provided for in this permit. (R307-415-6a(8))

Status: This is not an inspection item.

I.J Inspection and Entry.

I.J.1 Upon presentation of credentials and other documents as may be required by law, the
permittee shall allow the Director or an authorized representative to perform any of the
following:

I.J.1.a Enter upon the permittee's premises where the source is located or emissions related
activity is conducted, or where records are kept under the conditions of this permit.
(R307-415-6c(2)(a))

I.J.1.b Have access to and copy, at reasonable times, any records that must be kept under
the conditions of this permit. (R307-415-6c(2)(b))

I.J.1.c Inspect at reasonable times any facilities, equipment (including monitoring and air
pollution control equipment), practice, or operation regulated or required under this
permit. (R307-415-6c(2)(c))

I.J.1.d Sample or monitor at reasonable times substances or parameters for the purpose of
assuring compliance with this permit or applicable requirements.
(R307-415-6c(2)(d))

I.J.2 Any claims of confidentiality made on the information obtained during an inspection shall
be made pursuant to Utah Code Ann. Section 19-1-306. (R307-415-6c(2)(e))

Status: In Compliance. Entry was allowed during this inspection. Records have been provided as
requested.

I.K Certification.

Any application form, report, or compliance certification submitted pursuant to this permit
shall contain certification as to its truth, accuracy, and completeness, by a responsible
official as defined in R307-415-3. This certification shall state that, based on information
and belief formed after reasonable inquiry, the statements and information in the document
are true, accurate, and complete. (R307-415-5d)

Status: In Compliance. All application forms, reports, or compliance certifications submitted
pursuant to this permit in the past year appeared to have contained certification as to its
truth, accuracy, and completeness by a responsible individual as defined in R307-415-3.
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I.L Compliance Certification.

I.L.1 Permittee shall submit to the Director an annual compliance certification, certifying
compliance with the terms and conditions contained in this permit, including emission
limitations, standards, or work practices. This certification shall be submitted no later than
the date shown under "Enforceable Dates and Timelines" at the front of this permit, and that
date each year following until this permit expires. The certification shall include all the
following (permittee may cross-reference this permit or previous reports):
(R307-415-6c(5))

I.L.1.a The identification of each term or condition of this permit that is the basis of the
certification;

I.L.1.b The identification of the methods or other means used by the permittee for
determining the compliance status with each term and condition during the
certification period. Such methods and other means shall include, at a minimum, the
monitoring and related recordkeeping and reporting requirements in this permit. If
necessary, the permittee also shall identify any other material information that must
be included in the certification to comply with section 113(c)(2) of the Act, which
prohibits knowingly making a false certification or omitting material information;

I.L.1.c The status of compliance with the terms and conditions of the permit for the period
covered by the certification, including whether compliance during the period was
continuous or intermittent. The certification shall be based on the method or means
designated in Provision I.L.1.b. The certification shall identify each deviation and
take it into account in the compliance certification. The certification shall also
identify as possible exceptions to compliance any periods during which compliance
is required and in which an excursion or exceedance as defined under 40 CFR Part
64 occurred; and

I.L.1.d Such other facts as the Director may require to determine the compliance status.

I.L.2 The permittee shall also submit all compliance certifications to the EPA, Region VIII, at the
following address or to such other address as may be required by the Director:
(R307-415-6c(5)(d))

Environmental Protection Agency, Region VIII
Office of Enforcement, Compliance and Environmental Justice
(mail code 8ENF)
1595 Wynkoop Street
Denver, CO 80202-1129

Status: In Compliance. The last certification was received by DAQ on March 4, 2024. This report
was reviewed under separate cover and found to meet the requirements of this condition.

I.M Permit Shield.

I.M.1 Compliance with the provisions of this permit shall be deemed compliance with any
applicable requirements as of the date of this permit, provided that:

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I.M.1.a Such applicable requirements are included and are specifically identified in this
permit, or (R307-415-6f(1)(a))

I.M.1.b Those requirements not applicable to the source are specifically identified and listed
in this permit. (R307-415-6f(1)(b))

I.M.2 Nothing in this permit shall alter or affect any of the following:

I.M.2.a The emergency provisions of Utah Code Ann. Section 19-1-202 and Section 19-2-
112, and the provisions of the CAA Section 303. (R307-415-6f(3)(a))

I.M.2.b The liability of the owner or operator of the source for any violation of applicable
requirements under Utah Code Ann. Section 19-2-107(2)(a)(xiii) and Section 19-2-
110 prior to or at the time of issuance of this permit. (R307-415-6f(3)(b)).
[R307-415-6f]

I.M.2.c The applicable requirements of the Acid Rain Program, consistent with the CAA
Section 408(a). (R307-415-6f(3)(c))

I.M.2.d The ability of the Director to obtain information from the source under Utah Code
Ann. Section 19-2-120, and the ability of the EPA to obtain information from the
source under the CAA Section 114. (R307-415-6f(3)(d))

Status: Permit shields are listed in Section III of this permit.

I.N Emergency Provision.

I.N.1 An "emergency" is any situation arising from sudden and reasonably unforeseeable events
beyond the control of the source, including acts of God, which situation requires immediate
corrective action to restore normal operation, and that causes the source to exceed a
technology-based emission limitation under this 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 preventive maintenance,
careless or improper operation, or operator error. (R307-415-6g(1))

I.N.2 An emergency constitutes an affirmative defense to an action brought for noncompliance
with such technology-based emission limitations if the affirmative defense is demonstrated
through properly signed, contemporaneous operating logs, or other relevant evidence that:

I.N.2.a An emergency occurred and the permittee can identify the causes of the emergency.
(R307-415-6g(3)(a))

I.N.2.b The permitted facility was at the time being properly operated.
(R307-415-6g(3)(b))

I.N.2.c During the period of the emergency the permittee took all reasonable steps to
minimize levels of emissions that exceeded the emission standards, or other
requirements in this permit. (R307-415-6g(3)(c))

I.N.2.d The permittee submitted notice of the emergency to the Director within two
working days of the time when emission limitations were exceeded due to the
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emergency. This notice must contain a description of the emergency, any steps
taken to mitigate emissions, and corrective actions taken. This notice fulfills the
requirement of Provision I.S.2.c below. (R307-415-6g(3)(d))

I.N.3 In any enforcement proceeding, the permittee seeking to establish the occurrence of an
emergency has the burden of proof. (R307-415-6g(4))

I.N.4 This emergency provision is in addition to any emergency or upset provision contained in
any other section of this permit. (R307-415-6g(5))

Status: In Compliance. No emergency events were reported or recorded during the 12-month period
preceding this inspection.

I.O Operational Flexibility.

Operational flexibility is governed by R307-415-7d(1).

Status: This is not an inspection item.

I.P Off-permit Changes.

Off-permit changes are governed by R307-415-7d(2).

Status: This is not an inspection item.

I.Q Administrative Permit Amendments.

Administrative permit amendments are governed by R307-415-7e.

Status: This is not an inspection item.

I.R Permit Modifications.

Permit modifications are governed by R307-415-7f.

Status: This is not an inspection item.

I.S Records and Reporting.

I.S.1 Records.

I.S.1.a The records of all required monitoring data and support information shall be
retained by the permittee for a period of at least five years from the date of the
monitoring sample, measurement, report, or application. Support information
includes all calibration and maintenance records, all original strip-charts or
appropriate recordings for continuous monitoring instrumentation, and copies of all
reports required by this permit. (R307-415-6a(3)(b)(ii))

I.S.1.b For all monitoring requirements described in Section II, Special Provisions, the
source shall record the following information, where applicable:
(R307-415-6a(3)(b)(i))
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I.S.1.b.1 The date, place as defined in this permit, and time of sampling or
measurement.

I.S.1.b.2 The date analyses were performed.

I.S.1.b.3 The company or entity that performed the analyses.

I.S.1.b.4 The analytical techniques or methods used.

I.S.1.b.5 The results of such analyses.

I.S.1.b.6 The operating conditions as existing at the time of sampling or
measurement.

I.S.1.c Additional record keeping requirements, if any, are described in Section II, Special
Provisions.

I.S.2 Reports.

I.S.2.a Monitoring reports shall be submitted to the Director every six months, or more
frequently if specified in Section II. All instances of deviation from permit
requirements shall be clearly identified in the reports. (R307-415-6a(3)(c)(i))

I.S.2.b All reports submitted pursuant to Provision I.S.2.a shall be certified by a
responsible official in accordance with Provision I.K of this permit.
(R307-415-6a(3)(c)(i)

I.S.2.c The Director shall be notified promptly of any deviations from permit requirements
including those attributable to upset conditions as defined in this permit, the
probable cause of such deviations, and any corrective actions or preventative
measures taken. Prompt, as used in this condition, shall be defined as written
notification within the number of days shown under "Enforceable Dates and
Timelines" at the front of this permit. Deviations from permit requirements due to
breakdowns shall be reported in accordance with the provisions of R307-107.
(R307-415-6a(3)(c)(ii))

I.S.3 Notification Addresses.

I.S.3.a All reports, notifications, or other submissions required by this permit to be
submitted to the Director are to be sent to the following address or to such other
address as may be required by the Director:

Utah Division of Air Quality
P.O. Box 144820
Salt Lake City, UT 84114-4820
Phone: [phone]

I.S.3.b All reports, notifications or other submissions required by this permit to be
submitted to the EPA should be sent to one of the following addresses or to such
other address as may be required by the Director:

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For annual compliance certifications:

Environmental Protection Agency, Region VIII
Office of Enforcement, Compliance and Environmental Justice
(mail code 8ENF)
1595 Wynkoop Street
Denver, CO 80202-1129

For reports, notifications, or other correspondence related to permit modifications,
applications, etc.:

Environmental Protection Agency, Region VIII
Air Permitting and Monitoring Branch (mail code 8ARDP-PM)
1595 Wynkoop Street
Denver, CO 80202-1129
Phone: [phone].

Status: In Compliance. Records are kept as required. No deviations have been recorded or reported.
Monitoring reports have been submitted every six months.

I.T Reopening for Cause.

I.T.1 A permit shall be reopened and revised under any of the following circumstances:

I.T.1.a New applicable requirements become applicable to the permittee and there is a
remaining permit term of three or more years. No such reopening is required if the
effective date of the requirement is later than the date on which this permit is due to
expire, unless the terms and conditions of this permit have been extended pursuant
to R307-415-7c(3), application shield. (R307-415-7g(1)(a))

I.T.1.b The Director or EPA determines that this permit contains a material mistake or that
inaccurate statements were made in establishing the emissions standards or other
terms or conditions of this permit. (R307-415-7g(1)(c))

I.T.1.c EPA or the Director determines that this permit must be revised or revoked to
assure compliance with applicable requirements. (R307-415-7g(1)(d))

I.T.1.d Additional applicable requirements are to become effective before the renewal date
of this permit and are in conflict with existing permit conditions.
(R307-415-7g(1)(e))

I.T.2 Additional requirements, including excess emissions requirements, become applicable to a
Title IV affected source under the Acid Rain Program. Upon approval by EPA, excess
emissions offset plans shall be deemed to be incorporated into this permit.
(R307-415-7g(1)(b))

I.T.3 Proceedings to reopen and issue a permit shall follow the same procedures as apply to initial
permit issuance and shall affect only those parts of this permit for which cause to reopen
exists. (R307-415-7g(2))

Status: This is not an inspection item.
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I.U Inventory Requirements.

An emission inventory shall be submitted in accordance with the procedures of R307-150,
Emission Inventories. (R307-150)

Status: In Compliance. Emission inventories have been submitted as required.

I.V Title IV and Other, More Stringent Requirements

Where an applicable requirement is more stringent than an applicable requirement of
regulations promulgated under Title IV of the Act, Acid Deposition Control, both
provisions shall be incorporated into this permit. (R307-415-6a(1)(b))

Status: This is not an inspection item.

SECTION II: SPECIAL PROVISIONS

II.A Emission Unit(s) Permitted to Discharge Air Contaminants.
(R307-415-4(3)(a) and R307-415-4(4))

II.A.1 Permitted Source
Source-wide

II.A.2 Unit #1 Coal-fired Boiler (EU#1)
Rated at 9,225 MM Btu/hr; fired on bituminous & subbituminous coals, non-limited synthetic coal-
derived fuels, and refined coal (synfuel); using diesel /NG during startup, shutdown, upset, flame
stabilization; equipped with low-NOx burners, over-fire air-ports (OFA) system, bag house, FGD
scrubber.

II.A.3 Unit #2 Coal-fired Boiler (EU #2)
Rated at 9,225 MM Btu/hr; fired on bituminous & subbituminous coals, non-limited synthetic coal-
derived fuels, and refined coal (synfuel); using diesel/NG during startup, shutdown, upset, flame
stabilization; equipped with low-NOx burners, OFA system, bag house, FGD scrubber.

II.A.4 Main Boilers (EU #1 and 2)
Includes EU 1 and 2.

II.A.5 Coal Car Unloading Dust Collector 1A (EU #3)
Rated at 73,500 cfm with an air to cloth ratio of 6.4 : 1.

II.A.6 Coal Car Unloading Dust Collector 1B (EU #4
Rated at 73,500 cfm with an air to cloth ratio of 6.4 : 1.

II.A.7 Coal Car Unloading Dust Collector 1C (EU #5)
Rated at 73,500 cfm with an air to cloth ratio of 6.4 : 1.

II.A.8 Coal Car Unloading Dust Collector 1D (EU #6)
Rated at 73,500 cfm with an air to cloth ratio of 6.4 : 1.

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II.A.9 Coal Truck Unloading Dust Collector 2 (EU #7)
Rated at 6,000 cfm with an air to cloth ratio of 6.12 : 1.

II.A.10 Coal Reserve Reclaim Dust Collector 3 (EU #8)
Rated at 8,000 cfm with an air to cloth ratio of 5.44 : 1.

II.A.11 Coal Transfer Building #1 Dust Collector 4 (EU #9)
Rated at 34,000 cfm with an air to cloth ratio of 6.4 : 1.

II.A.12 Coal Transfer Building #2 Dust Collector 5 (EU #10)
Rated at 26,000 cfm with an air to cloth ratio of 6.29 : 1.

II.A.13 Coal Transfer Building #4 Dust Collector 6 (EU #11)
Rated at 17,500 cfm with an air to cloth ratio of 6.3 : 1.

II.A.14 Coal Crusher Building Dust Collector 11 (EU #12)
Rated at 18,000 cfm with an air to cloth ratio of 6.53 : 1.

II.A.15 U1 Generation Building Coal Dust Collector 13A (EU #13)
Rated at 33,000 cfm with an air to cloth ratio of 6.25 : 1.

II.A.16 U1 Generation Building Coal Dust Collector 13B (EU #14)
Rated at 16,500 cfm with an air to cloth ratio of 5.99 : 1.

II.A.17 U2 Generation Building Coal Dust Collector 14A (EU #15)
Rated at 19,500 cfm with an air to cloth ratio of 6.5 : 1.

II.A.18 U2 Generation Building Coal Dust Collector 14B (EU #16)
Rated at 16,500 cfm with an air to cloth ratio of 5.99 : 1.

II.A.19 Coal Pile Active and Reserve (EU #17)
The active pile has an unsealed portion and the reserve pile has a sealed portion. No unit-specific
applicable requirements

II.A.20 Coal Stackout (EU #18)
Includes active reclaim and reserve reclaim stacker areas. No unit-specific applicable requirements.

II.A.21 Fuel Oil Tank 1A (EU #19)
675,000 gallons, installed in 1981. No unit-specific applicable requirements.

II.A.22 Fuel Oil Tank 1B (EU #20)
675,000 gallons, installed in 1981. No unit-specific applicable requirements.

II.A.23 Limestone Unloading Dust Collector 1A (EU #21)
Rated 6,250 cfm with an air to cloth ratio of 5.2 : 1.

II.A.24 Limestone Unloading Dust Collector 1B (EU #22)
Rated 6,250 cfm with an air to cloth ratio of 5.2 : 1.

II.A.25 Limestone Transfer Dust Collector 1 (EU #23)
Rated 4,000 cfm with an air to cloth ratio of 5.45 : 1.
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II.A.26 Limestone Reclaim Dust Collector 2 (EU #24)
Rated 8,000 cfm with an air to cloth ratio of 5.45 : 1.

II.A.27 Limestone Silo Bin Vent Filter (EU #25)
Rated at 750 cfm with an air to cloth ratio of 2.2 : 1.

II.A.28 Limestone Crusher Dust Collector 3 (EU #26)
Rated 6,000 cfm with an air to cloth ratio of 6.12 : 1.

II.A.29 Limestone Preparation Dust Collector 4 (EU #27)
Rated 16,500 cfm with an air to cloth ratio of 5.99 : 1.

II.A.30 Limestone Storage Pile (EU #28)
A long term storage reserve and emergency stockpile. No unit-specific applicable requirements.

II.A.31 Lime Silo Dust Collector 1 (EU #29)
Rated at 2,320 cfm with an air to cloth ratio of 8 : 1.

II.A.32 Lime Hopper Dust Collector 2 (EU #30)
Rated at 2,320 cfm with an air to cloth ratio of 8 : 1.

II.A.33 Soda Ash Silo Dust Collector 3 (EU #31)
Rated at 1,200 cfm with an air to cloth ratio of 4.1 : 1.

II.A.34 Soda Ash Hopper Dust Collector 4 (EU #32)
Rated at 1,200 cfm with an air to cloth ratio of 3.8 : 1.

II.A.35 Fly Ash Silo Bin Vent Filter 1A (EU #33)
Rated at 4,845 dscfm per compressor with an air to cloth ratio of 3 : 1.

II.A.36 Fly Ash Silo Bin Vent Filter 1B (EU #34)
Rated at 4,845 dscfm per compressor with an air to cloth ratio of 3 : 1.

II.A.37 Combustion Byproducts Stackout & Stockpile (EU #35)
Includes main and emergency storage areas for conditioned sludge. No unit-specific applicable
requirements.

II.A.38 Combustion Byproduct Landfill (EU #36)
Conditioned sludge landfill. No unit-specific applicable requirements.

II.A.39 Unit 1 Cooling Tower 1A (EU #37)
Evaporative cooling tower. No unit-specific applicable requirements.

II.A.40 Unit 1 Cooling Tower 1B (EU #38)
Evaporative cooling tower. No unit-specific applicable requirements.

II.A.41 Unit 2 Cooling Tower 1A (EU #39)
Evaporative cooling tower. No unit-specific applicable requirements.

II.A.42 Unit 2 Cooling Tower 1B (EU #40)
Evaporative cooling tower. No unit-specific applicable requirements.
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II.A.43 Coal Sample Preparation Building Dust Collector (EU #41)
Rated at 8,610 cfm with 16 filter bags.

II.A.44 Sandblast Facility Dust Collector (EU #42)
Rated at 24,000 cfm with air to cloth ratio of 6.1:1.

II.A.45 U1 Gen. Bldg. Vacuum Cleaning Dust Collector (EU #43)
Rated at 2,450 scfm, with the capacity of 10 cubic yards with air to cloth ratio of 3 :1.

II.A.46 U2 Gen. Bldg. Vacuum Cleaning Dust Collector (EU #44)
Rated at 2,450 scfm, with the capacity of 10 cubic yards with air to cloth ratio of 3 :1.

II.A.47 U1 Fabric Filter Vacuum Cleaning Dust Collector (EU #45)
Rated at 1,850 scfm, with the capacity of 3 cubic yards with air to cloth ratio of 3 :1.

II.A.48 U2 Fabric Filter Vacuum Cleaning Dust Collector (EU#46)
Rated at 1,850 scfm, with the capacity of 3 cubic yards with air to cloth ratio of 3 :1.

II.A.49 GSB Vacuum Cleaning Dust Collector (EU #47)
Rated at 1,850 scfm, with the capacity of 3 cubic yards with air to cloth ratio of 3 :1.

II.A.50 Emergency Diesel Generators (EU #49)
Includes Generators 1A, 1B and 1C each equipped with a 4,000 HP diesel engine.

II.A.51 Class IIIb Industrial Waste Landfill (EU #50)
Handles most of trash and garbage generated on site. No unit-specific applicable requirements.

II.A.52 Paved Haul Road (EU #51)
Used for coal and limestone transportation. No unit-specific applicable requirements.

II.A.53 Unpaved Haul Roads (EU #52)
Used for combustion byproducts and sanitary Landfills. No unit-specific applicable requirements.

II.A.54 Solvent Parts Washers (EU #53)
The largest washer contains approximately 30 gallons of nonhalogenated solvent in a solvent reservoir.
Each washer's solvent reservoir is isolated from the ambient air. No unit-specific applicable requirements.

II.A.55 Diesel Driven Fire Pump 1B (EU #54)
An engine rated at 290 HP.

II.A.56 Diesel Driven Fire Pump 1C (EU #55)
An engine rated at 290 HP.

II.A.57 Emergency Diesel Fire Pump (EU #75)
An engine rated at 290 HP, diesel fire pump located at the Intermountain Community Center, but operated
by IPP

II.A.58 Emergency Fire Pumps (EU #77)
Includes EU #54, #55, and #75, subject to 40 CFR 63 Subpart ZZZZ

14
II.A.59 Coal Conveyers (EU #58)
Includes belts 1A, 1B, 2A, 2B, 3, 4, 5A, 5B, 6, 7, 8, 9A, 9B, 15A, 15B, 18A, 18B, 30, 201, 202, and
stacker conveyor.

II.A.60 Dust Collector Group 1 (EU #Group 1)
Includes EUs #3, #4, #5, #6, #9, #10, #11, #12, #13, #14, #15, #16, and #27.

II.A.61 Dust Collector Group 2 (EU #Group 2)
Includes EUs #7, #8, #21, #22, #23, #24, #25, #26, #29, #30, #31, #32, #33, #34, #41, #42, #43, #44, #45,
#46, and #47.

II.A.62 Paint Booth/Shops (EU #59)
Used for small equipment painting, non-architectural painting on-site, and auto painting. No unit-specific
applicable requirements.

II.A.63 Coal Truck Receiving Grating (EU #61)
Covers the coal truck unloading hopper. No unit-specific applicable requirements.

II.A.64 Bulb Recycling Crusher (EU #62)
Crushes waste fluorescent lamps on-site. No unit-specific applicable requirements.

II.A.65 Laboratory Fume Hoods (EU #63)
For testing water, oil, coal and miscellaneous samples. No unit-specific applicable requirements.

II.A.66 Gasoline Tank (EU #64)
Used to fuel vehicles at the Converter Station (500 gallons), installed in 1981. No unit-specific applicable
requirements.

II.A.67 Diesel Tank (EU #65)
Feeds the emergency diesel generators (10,000 gallon), installed in 1981. No unit-specific applicable
requirements.

II.A.68 Diesel Day Tanks (EU #66)
Contains diesel fuel for the Emergency Diesel Generators and Emergency diesel fire pumps (largest is
560 gallon), installed in 1981. No unit-specific applicable requirements.

II.A.69 Mobile Oil Storage Tanks (EU #67)
Used as temporary storage for dielectric oil (5,000 -12,000 gallon), installed in 1981. No unit-specific
applicable requirements.

II.A.70 Turbine Lube Oil Unit (EU #68)
Used to store turbine lube oil (up to 40,000 gallons per unit), installed in 1981. No unit-specific applicable
requirements.

II.A.71 Underground Storage Diesel Tank (EU #69)
Non-commercial onsite fueling (20,000 gallons), installed in 1981. No unit-specific applicable
requirements.

II.A.72 Underground Storage Gasoline Tank (EU #70)
Non-commercial onsite fueling (6,000 gallons), installed in 1981. No unit-specific applicable
requirements.
15
II.A.73 Used Oil Tank (EU #71)
10,000 gallons, installed in 1981. No unit-specific applicable requirements.

II.A.74 Helper Cooling Tower 1C (EU #72)
Unit 1 evaporative helper cooling tower. No unit-specific applicable requirements.

II.A.75 Helper Cooling Tower 2C (EU #73)
Unit 2 evaporative helper cooling tower. No unit-specific applicable requirements.

II.A.76 ICS Cooling Towers (EU #74)
8 cooling towers used at the Intermountain Convertor Station and auxiliary equipment. No unit-specific
applicable requirements.

II.A.77 On Road Diesel Tank (EU #76)
Non-commercial Ultra Low Sulfur Highway Diesel fuel tank (500 gallons), installed in 2012. No unit-
specific applicable requirements.

Status: In Compliance. No unapproved equipment was observed.

II.B Requirements and Limitations

The following emission limitations, standards, and operational limitations apply to the permitted facility
as indicated:

II.B.1 Conditions on Permitted Source (Source-wide).

II.B.1.a Condition:

The permittee shall not discharge into the atmosphere from any abrasive blasting any air contaminant for
a period or periods aggregating more than three minutes in any one hour which is a shade or density
darker than 40%. [Origin: DAQE-AN103270030-22 and R307-206]. [R307-206, R307-401-8]

II.B.1.a.1 Monitoring:

Visible emission evaluation shall be conducted every six months in accordance with the
following procedure, if abrasive blasting operations are conducted.

(a) Visible emissions shall be measured using EPA Method 9. Visible emissions from
intermittent sources shall use procedures similar to Method 9, but the requirement for
observations to be made at 15 second intervals over a six-minute period shall not apply.

(b) Emissions from unconfined blasting shall be read at the densest point of the emission after a
major portion of the spent abrasive has fallen out, at a point not less than five feet nor more than
twenty-five feet from the impact surface from any single abrasive blasting nozzle.

(c) Emissions from unconfined blasting employing multiple nozzles shall be judged as a single
source unless it can be demonstrated by the permittee that each nozzle, evaluated separately,
meets the emission and performance standards provided for in R307-206-2 through 4.

(d) Emissions from confined blasting shall be read at the densest point after the air contaminant
leaves the enclosure. [R307-205-5]
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II.B.1.a.2 Recordkeeping:

Results of monitoring shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.1.a.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. All abrasive blasting has been confined. Visible emissions evaluations have been
performed and recorded every six months.

II.B.1.b Condition:

Emissions from sources of fugitive dust shall be minimized. Any haul road speeds established in the
plant shall be posted. [Origin: DAQE-AN0103270030-22]. [R307-205-5]

II.B.1.b.1 Monitoring:

Adherence to the most recently approved fugitive dust control plan shall be monitored to
demonstrate that appropriate measures are being implemented to control fugitive dust.

II.B.1.b.2 Recordkeeping:

Records of measures taken to minimize fugitive dust shall be maintained as described in
Provision I.S.1 of this permit.

II.B.1.b.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. Intermountain Power is following a fugitive dust control plan approved by DAQ
on January 14, 2005. Magnesium chloride is applied to haul roads annually. Water trucks operate
full time during the drier months. The plan includes a six-tiered dust control plan, with the final
tier being shutting down activity in order to minimize fugitive dust. Records of daily monitoring
were provided. Roads were sufficiently wetted and no fugitive dust was observed during this
inspection.

II.B.1.c Condition:

At all times, including periods of startup, shutdown, and malfunction, the permittee shall, to the extent
practicable, maintain and operate any permitted plant equipment, including associated air pollution
control equipment, in a manner consistent with good air pollution control practice for minimizing
emissions. Determination of whether acceptable operating and maintenance procedures are being used
will be based on information available to the Director which may include, but is not limited to,
monitoring results, opacity observations, review of operating and maintenance procedures, and inspection
of the source. [Origin: DAQE-AN0103270030-22]. [40 CFR 60 Subpart A, R307-401-8(2)]

17
II.B.1.c.1 Monitoring:

Records required for this permit condition will serve as monitoring.

II.B.1.c.2 Recordkeeping:

Records documenting scheduled and unscheduled maintenance shall be maintained. A copy of
all manufacturers' instructions, established operating instructions, or established maintenance
practices for pollution control equipment and pollution emitting equipment shall be kept on site.
These instructions shall be available to all employees who operate the equipment and shall be
made available to compliance inspectors upon their request. Records shall be maintained in
accordance with Provision I.S.1 of this permit.

II.B.1.c.3 Reporting:

In addition to the reports required in Section I of this permit, the following reports shall be
submitted:

(a) An annual projection of planned outages for steam boilers and associated pollution control
equipment shall be submitted to the Director not later than January 30 for each calendar year.

(b) Changes to the schedule of planned outages shall be reported to the Director within 96 hours
after the start of the outage.

(c) Maintenance outages shall be reported promptly or according to other applicable reporting
criteria in Provision I.S.

Status: In Compliance. The facilities appeared to be well maintained. A preventative maintenance
database called Maximo is in place and utilizes a work order program to track and record all
maintenance activities. Annual planned outage projections have been submitted to the Executive
Secretary. Unscheduled maintenance outages have been promptly reported. The permittee also
submits follow-up letters to document these unplanned outages.

II.B.1.d Condition:

A Risk Management Plan (RMP) developed in accordance with 40 CFR Part 68 shall be submitted to the
United States Environmental Protection Agency not later than the applicable date in 40 CFR 68.
[Origin: 40 CFR 68]. [40 CFR 68]

II.B.1.d.1 Monitoring:

A copy of the Risk Management Plan shall be available upon request along with a copy of the
transmittal letter to EPA.

II.B.1.d.2 Recordkeeping:

A copy of the Risk Management Plan shall be available to the Director upon request along with a
copy of the transmittal letter to EPA. Records shall be maintained in accordance with Provision
I.S.1.

18
II.B.1.d.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. A Risk Management Plan is in place. The most recent plan was submitted in April
2024.

II.B.1.e Condition:

The permittee shall comply with the applicable requirements for servicing of motor vehicle air
conditioners pursuant to 40 CFR 82, Subpart B - Servicing of Motor Vehicle Air Conditioners.
[Origin: 40 CFR 82.30(b)]. [40 CFR 82 Subpart B]

II.B.1.e.1 Monitoring:

The permittee shall certify, in the annual compliance statement required in Section I of this
permit, its compliance status with the requirements of 40 CFR 82, Subpart B.

II.B.1.e.2 Recordkeeping:

All records required in 40 CFR 82, Subpart B shall be maintained consistent with the
requirements of Provision S.1 in Section I of this permit.

II.B.1.e.3 Reporting:

All reports required in 40 CFR 82, Subpart B shall be submitted as required. There are no
additional reporting requirements except as outlined in Section I of this permit.

Status: In Compliance. The permittee certified compliance with this condition in the most recent annual
compliance certification.

II.B.1.f Condition:

The permittee shall comply with the applicable requirements for recycling and emission reduction for
class I and class II refrigerants pursuant to 40 CFR 82, Subpart F - Recycling and Emissions Reduction.
[Origin: 40 CFR 82.150(b)]. [40 CFR 82 Subpart F]

II.B.1.f.1 Monitoring:

The permittee shall certify, in the annual compliance statement required in Section I of this
permit, its compliance status with the requirements of 40 CFR 82, Subpart F.

II.B.1.f.2 Recordkeeping:

All records required in 40 CFR 82, Subpart F shall be maintained consistent with the
requirements of Provision S.1 in Section I of this permit.

19
II.B.1.f.3 Reporting:

All reports required in 40 CFR 82, Subpart F shall be submitted as required. There are no
additional reporting requirements except as outlined in Section I of this permit.

Status: In Compliance. The permittee certified compliance with this condition in the most recent annual
compliance certification.

II.B.1.g Condition:

The permittee shall submit documentation of the status of construction of the new combustion turbine
plant to the Director before December 22, 2023. AO DAQE-AN103270030-22 may become invalid if
construction is not commenced within 18 months from June 22, 2022 or if construction is discontinued
for 18 months or more. To ensure proper credit when notifying the Director, send the documentation to
the Director, attn.: NSR Section. [Origin: DAQE-AN103270030-22]. [R307-401-8]

II.B.1.g.1 Monitoring:

Records required for this permit condition will serve as monitoring.

II.B.1.g.2 Recordkeeping:

The permittee shall maintain a copy of each notification required by this permit condition in
accordance with Provision I.S.1 of this permit.

II.B.1.g.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. A status of construction notice was submitted in November 2022 but a copy could
not be found in DAQ source files. A copy is attached.

II.B.1.h Condition:

The equipment listed in Section II.A of this permit shall remain in operation until such time as the new
Combustion Turbine Plant is installed and operational. The new Combustion Turbine Plant will become
operational only after a reasonable shakedown period, not to exceed 180 days. At that time the listed
Equipment in Section II.A of this permit, except II.A 31 through 34, 51 through 58, 62, 64, 66 through 69,
73, 76, and 77, shall cease operations and be removed from service.

Conditions II.B.2, 3, 5, and 6 of this permit shall not apply to the permittee once the equipment has been
removed from service.

Condition II.B.7 shall apply to the dust collectors in II.A.31 through 34 only once the other dust collectors
listed in II.A.61 (Dust Collector Group 2) cease operations.

The permittee shall file a complete application to obtain an operating permit revision within 12 months
after commencing operation of the new Combustion Turbine plant as required by R307-415-5a(1)

[Origin: DAQE-AN103270030-22 and R307-415-5a(1)]. [R307-401-8, R307-415]
20
II.B.1.h.1 Monitoring:

Records required for this permit condition will serve as monitoring.

II.B.1.h.2 Recordkeeping:

Records documenting of the status of operation of the new Combustion Turbine Plant and the
copy of application to obtain an operating permit revision shall be maintained in accordance with
Provision I.S.1 of this permit.

II.B.1.h.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: Not Applicable at this time. The new Combustion Turbine Plant has not been fully constructed.

II.B.2 Conditions on Main Boilers (EU #1 and #2).

II.B.2.a Condition:

Emissions of NOx from each boiler shall not exceed 0.461 lb/MMBtu heat input, based on a 30-day
rolling average as determined by the arithmetic average of all hourly emission rates for the 30 successive
boiler operating days, at all times except during periods of startup, shutdown, or malfunction. [Origin:
DAQE-AN0103270030-22]. [40 CFR 60 Subpart Da, R307-401-8]

II.B.2.a.1 Monitoring:

(a) The permittee shall install, calibrate, maintain, and operate a continuous monitoring system,
and record the output of the system, for measuring nitrogen oxides emissions. The permittee
shall determine compliance in accordance with 40 CFR Part 60.48a, Compliance provision
(subparagraphs (b), (c), (e), (g) and (h), 60.49a, Emission monitoring (subparagraphs (c), (d), (e),
(f), (g), (h), (i), and (j)), and 60.50a, Compliance determination procedures and methods
(subparagraph (d)).

(b) Each continuous emission monitoring system shall meet the following requirements as
specified in 40 CFR Part 75 Appendix A, Specification and Test Procedures:

(1) Installation and Measurement Location
(2) Equipment Specifications (except the requirement for a low range in 2.1.1.2)
(3) Performance Specifications
(4) Data Acquisition and Handling Systems
(5) Calibration Gas

(c) The permittee shall implement a Quality Control program according to 40 CFR Part 75
Appendix B, Procedure 1, Quality Control Program, and Appendix B, Procedure 2, Frequency of
Testing, except Procedure 2.1.5, Procedure 2.2.3 and Procedure 2.3.2, which define the out-of
control periods for the daily, quarterly, semiannual and annual assessments, respectively. The
following requirements shall be used to define the out-of-control criteria for the emission data:

(1) 40 CFR Part 60, Appendix F, Procedure 4.3, Criteria for Excessive Calibration Drift
21
(2) CFR Part 60, Appendix F, Procedure 5.2, Excessive Audit Inaccuracy
(3) 40 CFR Part 60, Appendix F, Procedure 6, Calculations for CEMS Data Accuracy.

II.B.2.a.2 Recordkeeping:

(a) The permittee shall maintain a file of 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 and maintenance performed on these systems or devices; and all
other information required by applicable portions of 40 CFR Part 60, Subparts A and Da recorded
in a permanent form suitable for inspection. (40 CFR 60.7(f))

(b) The permittee shall maintain records of the occurrence and duration of any startup, shutdown,
or malfunction in the operation of the unit; any malfunction of the air pollution control
equipment; or any periods during which a continuous monitoring system or monitoring device is
inoperative (40 CFR 60.7(b) & (f) and R307-415-6a(3)(b)(ii)).

(c) Records shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.2.a.3 Reporting:

(a) The permittee shall submit excess emission reports required by 40 CFR 60.7(c) and (d) and 40
CFR 60.51a, Reporting requirements. A data assessment report required by Appendix F,
Procedure 1, Section 7 to 40 CFR Part 60 shall be submitted with the excess emission report.

(b) Relative Accuracy Test Audit notifications shall be made in accordance with R307-170,
Continuous Emission Monitoring System Program.

(c) The permittee shall submit notifications and reports to the Director as required by R307-170,
Continuous Emission Monitoring Systems Program.

(d) A copy of all reports required by 40 CFR Part 60 to be submitted to the Director (permitting
authority) shall also be submitted to USEPA, Region VIII, if requested. (40 CFR 60.4 and
60.7(c))

(e) The reports required in paragraphs a, b, and c above are considered prompt notification of
permit deviations required in provision I.S.2.c of this permit if all information required by
provision I.S.2.c is included in the report.

(f) Deviations from permit requirements due to unavoidable breakdowns shall be reported in
accordance with the provisions of R307-107.

Status: Not Evaluated. Continuous monitoring requirements are evaluated by DAQ’s CEM specialist.

II.B.2.b Condition:

Emissions of PM10 from each boiler shall not exceed 0.0184 lb/MMBtu at all times except during periods
of startup, shutdown, or malfunction. [Origin: DAQE-AN0103270030-22]. [40 CFR 60 Subpart Da,
R307-401-8]

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II.B.2.b.1 Monitoring:

(a) Opacity shall be used as a primary indicator and scrubber SO2 removal rate shall be used as a
secondary indicator to provide a reasonable assurance of compliance with the PM10 emission
limitation as specified below:

(1) Primary Indicator - Opacity

(i) Measurement Approach: Opacity shall be determined by using a COM located in the
ductwork just downstream of the baghouse and upstream of the SO2 scrubber.

(ii) Indicator Range: An excursion is defined as hourly block average opacity measurements in
excess of 45% as measured by a COM, except for periods of startup, shutdown, or malfunction.
Excursions trigger an inspection and review of baghouse performance as indicated by other
parameters (to confirm if opacity is valid and to determine baghouse operating deficiencies),
corrective action, and a reporting requirement. If hourly block average opacity is greater than
10% but less than 45% as measured by a COM, except for periods of startup, shutdown,
maintenance/planned outage or malfunction, the scrubber SO2 removal rate, as a secondary
indicator to show a reasonable assurance of compliance with the PM10 emission limitation, shall
be monitored simultaneously as specified in (A)(2) of this monitoring condition. Condition
II.B.2.b.1(a)(1)(ii) of this permit does not constitute a waiver, nor a shield against enforcement, of
condition II.B.2.e of this permit condition.

(iii) Performance Criteria:
(aa) Data Representativeness: Measurements made by a COM shall provide a direct indicator of
baghouse performance. Each COM shall be installed and operated in accordance with 40 CFR
60.47a, Emission Monitoring (subparagraphs (a), (e), (f), and (i), and 60.13, Monitoring
Requirements (subparagraphs (e) and (h), and meeting the quality assurance requirements
outlined at 40 CFR 60.13 (d) and (e); 40 CFR Part 60, Appendix B, Performance Specification 1,
and R307-170.
(bb) QA/QC Practices and Criteria: Each COM shall be operated, calibrated, and maintained to
meet 40 CFR 60, Appendix B, Performance Specification 1.
(cc) Monitoring Frequency: Opacity shall be monitored continuously and a data point recorded
every 10 seconds.
(dd) Data Collection Procedure: Opacity data shall be recorded and stored electronically.
(ee) Averaging Period: Use the 10-second opacity data to calculate 6-minute averages and the 6-
minute averages to calculate the hourly block average opacity.

(2) Secondary Indicator - Scrubber SO2 removal rate

(i) Measurement Approach: SO2 removal rate is measured directly by CEM, which provide the
single best indicator of wet scrubber performance.

(ii) Indicator Range: An excursion is defined as hourly block average opacity measurements in
excess of 10% as measured by a COM, except for periods of startup, shutdown, or malfunction,
and SO2 removal rate simultaneously below 90%, based upon a 24 hour rolling average.
Excursions trigger an inspection and review of baghouse and scrubber performance as indicated
by other parameters (to confirm if opacity is valid and to determine baghouse and scrubber
operating deficiencies), corrective action, and a reporting requirement.

23
(iii) Performance Criteria:
(aa) Data Representativeness: Measurements are made by a CEM located before and after the wet
flue gas desulfurization scrubber, providing a direct indicator of scrubber performance. Each
CEM shall be installed, calibrated, and maintained as required by the applicable performance
specification.
(bb) QA/QC Practices and Criteria: Each CEM shall be operated, calibrated, and maintained to
meet 40 CFR 60, Appendix B, Performance Specification 2.
(cc) Monitoring Frequency: SO2 removal rate shall be measured every 15 minutes whenever the
hourly block average opacity measured by COM exceeds 10%.
(dd) Data Collection Procedure: SO2 removal data shall be recorded and stored electronically.
(ee) Averaging Period: Use the 15-minute data to calculate hourly averages and the hourly
averages to calculate a 24-hour rolling average. A 24-hour average SO2 removal rate shall be
calculated for each 24-hour period during which the hourly block average opacity measured by
COM exceeds 10%.

(b) Stack testing shall be performed as specified below:

(1) Frequency. PM10 emissions shall be tested annually. The source may also be tested at any
time if directed by the Director.

(2) Notification. At least 30 days before the test, the source shall notify the Director of the date,
time, and place of testing and provide a copy of the test protocol. The source shall attend a
pretest conference if determined necessary by the Director.

(3) Methods.

(i) Sample Location - the emission point shall conform to the requirements of 40 CFR 60,
Appendix A, Method 1, and Occupational Safety and Health Administration (OSHA) approved
access shall be provided to the test location.

(ii) Compliance determination procedures and stack testing shall be performed according to 40
CFR 60, Appendix A, Method 5B.

(4) Calculations. To determine mass emission rates (lb/hr, etc.) the pollutant concentration as
determined by the appropriate methods above shall be multiplied by the volumetric flow rate and
any necessary conversion factors determined by the Director to give the results in the specified
units of the emission limitation.

(5) Production Rate During Testing. The production rate during all compliance testing shall be
no less than 90% of the maximum production achieved in the previous three (3) years.

II.B.2.b.2 Recordkeeping:

In addition to the recordkeeping requirement described in Provision I.S.1 of this permit,

(a) The permittee shall maintain a file of all stack testing and all other information required by
permit provision I.S.1 and applicable portions of 40 CFR Part 60, Subparts A and Da recorded in
a permanent form suitable for inspection. (40 CFR 60.7(f))

(b) The permittee shall maintain a file of all continuous opacity monitor (COM) measurements,
including performance testing measurements, all COM performance evaluations, all COM
24
calibration checks, all COMs adjustments and maintenance, and all other information required by
applicable portions of 40 CFR Part 60, Subparts A and Da recorded in a permanent form suitable
for inspection. (40 CFR 60.7(f)).

(c) The permittee shall maintain records of the occurrence and duration of any startup, shutdown,
or malfunction in the operation of the unit; or any malfunction of the air pollution control
equipment. (40 CFR 60.7(b)).

(d) The permittee shall maintain a file of the occurrence and duration of any excursion, corrective
actions taken, and any other supporting information required to be maintained under 40 CFR 64
(such as data used to document the adequacy of monitoring, or records of monitoring
maintenance or corrective actions). Instead of paper records, the permittee may maintain 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 inspection and review, and
does not conflict with other applicable recordkeeping requirements. (40 CFR 64.9(b)).

II.B.2.b.3 Reporting:

(a) The monitoring report required in Provision I.S.2 of this permit shall include, at a minimum,
the following information, as applicable:

(1) Summary information on the number, duration and cause (including unknown cause, if
applicable) of excursions or exceedances, as applicable, and the corrective actions taken;(40 CFR
64.9(a)(2)(i))

(2) Summary information on the number, duration and cause (including unknown cause, if
applicable) for monitor downtime incidents (other than downtime associated with zero and span
or other daily calibration checks, if applicable). (40 CFR 64.9(a)(2)(ii))

(b) The results of stack testing shall be submitted to the Director within 60 days of completion of
the testing. Reports shall clearly identify results as compared to permit limits and indicate
compliance status.

Status: In Compliance with stack testing requirements. Continuous monitoring requirements are
evaluated by DAQ’s CEM specialist.

Stack testing was last performed September 13-14, 2024. Test results were submitted to DAQ and
audited in DAQC-1326-23. DAQ calculated results for PM10 were 0.0036 lb/MMBtu from Unit 1,
and 0.0024 lb/MMBtu from Unit 2.

II.B.2.c Condition:

Emissions of SO2 from each boiler shall not exceed 0.138 lb/MMBtu, based on a 30-day rolling average
as determined by the arithmetic average of all hourly emission rates for the 30 successive boiler operating
days, at all times except for data obtained during emergency conditions and 40 CFR 60.48Da(d)
procedures are implemented. [Origin: DAQE-AN0103270030-22]. [40 CFR 60 Subpart Da, R307-401-8]

25
II.B.2.c.1 Monitoring:

(a) The permittee shall install, calibrate, maintain, and operate a continuous monitoring system,
and record the output of the system, for measuring sulfur dioxide emissions. The permittee shall
determine compliance in accordance with 40 CFR Part 60.48Da, Compliance provision
(subparagraph (c), (d), (e), and (h)), 60.49Da, Emission monitoring (subparagraph (b), (d), (e),
(f), (g), (h), (i) and (j)), and 60.50Da, Compliance determination procedures and methods
(subparagraph (c)).

(b) Each continuous emission monitoring system shall meet the following requirements as
specified in 40 CFR Part 75, Appendix A, Specification and Test Procedures:

(1) Installation and Measurement Location
(2) Equipment Specifications (except the requirement for a low range in 2.1.1.2)
(3) Performance Specifications
(4) Data Acquisition and Handling Systems
(5) Calibration Gas

(c) The permittee shall implement a Quality Control program according to 40 CFR Part 75,
Appendix B, Procedure 1, Quality Control Program and Appendix B, Procedure 2, Frequency of
Testing except Procedure 2.1.5, Procedure 2.2.3 and Procedure 2.3.2, which define the out-of
control periods for the daily, quarterly, semiannual and annual assessments, respectively. The
following requirements shall be used to define the out-of-control criteria for the emission data:

(1) 40 CFR Part 60, Appendix F, Procedure 4.3, Criteria for Excessive Calibration Drift
(2) 40 CFR Part 60, Appendix F, Procedure 5.2, Excessive Audit Inaccuracy
(3) 40 CFR Part 60, Appendix F, Procedure 6, Calculations for CEMS Data Accuracy.

II.B.2.c.2 Recordkeeping:

(a) The permittee shall maintain a file of 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 and maintenance performed on these systems or devices; and all
other information required by applicable portions of 40 CFR Part 60, Subparts A and Da recorded
in a permanent form suitable for inspection. (40 CFR 60.7(f))

(b) The permittee shall maintain records of the occurrence and duration of any startup, shutdown,
or malfunction in the operation of the unit; any malfunction of the air pollution control
equipment; or any periods during which a continuous monitoring system or monitoring device is
inoperative. (origin: 40 CFR 60.7(b) & (f) and R307-415-6a(3)(b)(ii)).

II.B.2.c.3 Reporting:

(a) The permittee shall submit excess emission reports required by 40 CFR 60.7(c) and (d) and 40
CFR 60.51a, Reporting requirements. A data assessment report required by Appendix F,
Procedure 1, Section 7 to 40 CFR Part 60 shall be submitted with the excess emission report.

(b) Relative Accuracy Test Audit notifications shall be made in accordance with R307-170,
Continuous Emission Monitoring System Program.

26
(c) The permittee shall submit notifications and reports to the Director as required by R307-170,
Continuous Emission Monitoring Systems Program.

(d) A copy of all reports required by 40 CFR Part 60 to be submitted to the Director (permitting
authority) shall also be submitted to USEPA, Region VIII, if requested. (40 CFR 60.4 and
60.7(c))

(e) The reports required in paragraphs a, b, and c above are considered prompt notification of
permit deviations required in provision I.S.2.c of this permit if all information required by
provision I.S.2.c is included in the report.

(f) Deviations from permit requirements due to unavoidable breakdowns shall be reported in
accordance with the provisions of R307-107.

Status: Not Evaluated. Continuous monitoring requirements are evaluated by DAQ’s CEM specialist.

II.B.2.d Condition:

Emissions of SO2 shall be no greater than 10 percent of the potential combustion concentration based on
the average inlet and average outlet SO2 emissions determined as the arithmetic average of all hourly
emission rates for the 30 successive boiler operating days for each boiler.
[Origin: 40 CFR 60.43Da(l)(2)(ii)]. [40 CFR 60 Subpart Da]

II.B.2.d.1 Monitoring:

(a) The permittee shall install, calibrate, maintain, and operate a continuous monitoring system,
and record the output of the system, for measuring sulfur dioxide emissions. The permittee shall
determine compliance in accordance with 40 CFR Part 60.48Da, Compliance provision
(subparagraph (c), (d), (e), (g) and (h)), 60.49Da, Emission monitoring (subparagraph (b), (d), (e),
(f), (g), (h), (i) and (j)), and 60.50Da, Compliance determination procedures and methods
(subparagraph (c)).

(b) SO2 inlet monitor shall meet the following requirements:
(1) 40 CFR Part 60, Appendix B, Specifications and Test Procedures for SO2 and NOx
Continuous Emission monitoring Systems in Stationary Sources
(2) 40 CFR Part 60, Appendix F, Quality Assurance Procedures

(c) The permittee shall implement a Quality Control program for the SO2 outlet monitors
according to 40 CFR Part 75, Appendix B, Procedure 1, Quality Control Program and Appendix
B, Procedure 2, Frequency of Testing except Procedure 2.1.5, Procedure 2.2.3 and Procedure
2.3.2, which define the out-of control periods for the daily, quarterly, semiannual and annual
assessments, respectively. The following requirements shall be used to define the out-of-control
criteria for the emission data:
(1) 40 CFR Part 60, Appendix F, Procedure 4.3, Criteria for Excessive Calibration Drift
(2) 40 CFR Part 60, Appendix F, Procedure 5.2, Excessive Audit Inaccuracy
(3) 40 CFR Part 60, Appendix F, Procedure 6, Calculations for CEMS Data Accuracy

(d) An "as-fired" fuel monitoring system (upstream of coal pulverizers) meeting the requirements
of Method 19 (40 CFR Part 60 Appendix A) may be used as an alternative method to determine
potential sulfur dioxide emissions in place of a continuous sulfur dioxide emission monitor at the
inlet to the sulfur dioxide control device. (60.49Da(b)(3)).
27
II.B.2.d.2 Recordkeeping:

(a) The permittee shall maintain a file of 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 and maintenance performed on these systems or devices; and all
other information required by applicable portions of 40 CFR Part 60, Subparts A and Da recorded
in a permanent form suitable for inspection. (40 CFR 60.7(f))

(b) The permittee shall maintain records of the occurrence and duration of any startup, shutdown,
or malfunction in the operation of the unit; any malfunction of the air pollution control
equipment; or any periods during which a continuous monitoring system or monitoring device is
inoperative (origin: 40 CFR 60.7(b) & (f) and R307-415-6a(3)(b)(ii)).

(c) Records shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.2.d.3 Reporting:

(a) The permittee shall submit excess emission reports required by 40 CFR 60.7(c) and (d) and 40
CFR 60.51a, Reporting requirements. A data assessment report required by Appendix F,
Procedure 1, Section 7 to 40 CFR Part 60 shall be submitted with the excess emission report.

(b) Relative Accuracy Test Audit notifications shall be made in accordance with R307-170,
Continuous Emission Monitoring System Program.

(c) The permittee shall submit notifications and reports to the Director as required by R307-170,
Continuous Emission Monitoring Systems Program.

(d) A copy of all reports required by 40 CFR Part 60 to be submitted to the Director (permitting
authority) shall also be submitted to USEPA, Region VIII, if requested. (40 CFR 60.4 and
60.7(c))

(e) The reports required in paragraphs a, b, and c above are considered prompt notification of
permit deviations required in provision I.S.2.c of this permit if all information required by
provision I.S.2.c is included in the report.

(f) Deviations from permit requirements due to unavoidable breakdowns shall be reported in
accordance with the provisions of R307-107.

Status: Not Evaluated. Continuous monitoring requirements are evaluated by DAQ’s CEM specialist.

II.B.2.e Condition:

Visible emissions shall be no greater than 20 percent opacity (six-minute average) for each boiler except
for one six-minute period per hour of not more than 27 percent opacity and except during periods of start-
up, shutdown, or malfunction. [Origin: DAQE-AN0103270030-22].
[40 CFR 60 Subpart Da, R307-401-8

28
II.B.2.e.1 Monitoring:

(a) The permittee shall determine compliance with the visible emission limit by periodic
monitoring using a continuous opacity monitoring (COM) system installed and operated in
accordance with 40 CFR 60.49Da, Emission monitoring (subparagraphs (a), (e), (f), and (i)), and
60.13, Monitoring requirements (subparagraphs (e) and (h)).

(b) Each continuous opacity monitoring system shall meet the following quality assurance
requirements:

(1) 40 CFR 60.13, Monitoring requirements (subparagraphs (d) and (f))
(2) 40 CFR Part 60, Appendix B, Performance Specification 1, Specifications and Test
Procedures or Opacity Continuous Emission Monitoring Systems in Stationary Sources
(3) R307-170, Continuous Emission Monitoring System Program.

II.B.2.e.2 Recordkeeping:

(a) The permittee shall maintain a file of 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 and maintenance performed on these systems or devices; and all
other information required by applicable portions of 40 CFR Part 60, Subparts A and Da recorded
in a permanent form suitable for inspection. (40 CFR 60.7(f))

(b) The permittee shall maintain records of the occurrence and duration of any startup, shutdown,
or malfunction in the operation of the unit; any malfunction of the air pollution control
equipment; or any periods during which a continuous monitoring system or monitoring device is
inoperative (40 CFR 60.7(b)).

(c) Records demonstrating compliance with this condition shall be maintained in accordance with
Provision I.S.1 of this permit.

II.B.2.e.3 Reporting:

(a) The permittee shall submit excess emission reports required by 40 CFR 60.7(c) and (d) and 40
CFR 60.51a, Reporting requirements. A data assessment report required by Appendix F,
Procedure 1, Section 7 to 40 CFR Part 60 shall be submitted with the excess emission report.

(b) The permittee shall submit notifications and reports to the Director as required by R307-170,
Continuous Emission Monitoring Systems Program.

(c) A copy of all reports required by 40 CFR Part 60 to be submitted to the Director (permitting
authority) shall also be submitted to USEPA, Region VIII, if requested. (40 CFR 60.4 and
60.7(c))

(d) The reports required in paragraphs a, and b above are considered prompt notification of
permit deviations required in provision I.S.2.c of this permit if all information required by
provision I.S.2.c is included in the report.

(e) Deviations from permit requirements due to unavoidable breakdowns shall be reported in
accordance with the provisions of R307-107.

Status:

Not Evaluated. Continuous monitoring requirements are evaluated by DAQ’s CEM specialist.
29
II.B.2.f Condition:

Emissions of CO shall be not greater than 1320 lbs/hour monthly block average from each boiler.
[Origin: DAQE-AN0103270030-22]. [R307-401-8]

II.B.2.f.1 Monitoring:

(a) Combustion flue gas percent O2 shall be monitored and recorded at least once per 15 minutes
at the exit path of each boiler. Measurements are weighted average results collected from several
sensors located in each boiler exit flue path. Calibrations shall be maintained within
manufacturer's recommendations.

(b) OFA operating condition shall be monitored and recorded at least once per 15 minutes.
Monitoring shall include OFA position and status: i.e., No OFA, 1/3 OFA, 2/3 OFA, throttled or
open. Operational status is measured by OFA system damper position.

(c) Using the data above and this formula, CO concentration (ppmdv) shall be calculated and
averaged hourly, except for periods of calibration, maintenance, or malfunction of the
instrumentation or data system. For periods of calibration, maintenance, or malfunction of
instrumentation or data collection system, missing data shall be back filled following procedures
similar to 40 CFR Part 75 Subpart D, and used for compliance determinations.

[Cppmvd] = n * (O2%)a

Where:

[Cppmvd] = concentration of CO in parts per million volume dry
n = curve specific factor obtained from the table below
O2% = percent O2 measured at the boiler stack exit
a = curve specific exponent obtained from the table below

Values for n and a factors
Position n a
No OFA 47259 -7.6817
1/3 OFA 66265 -7.9824
2/3 OFA - throttled 4029.2 -4.0112
2/3 OFA - full open 1372.4 -3.0919

(d) The hourly mass emission rates in lb per hour shall be calculated using the following formula
or any necessary conversion factors determined by the Director, to give the results in the
specified units of the emission limitation.

[Clb/hr] = [Cppmvd] * 2.59 * 10-9 * MW * Fd * 20.9/(20.9-O2%) * HI
where:

[Clb/hr] = pound per hour emission rate
[Cppmvd] = hourly average of CO emissions in parts per million
2.59*10-9 = conversion factor for pound per standard cubic feet
MW = molecular weight of CO
Fd = F factor to convert standard cubic feet per million Btu heat input.
30
O2% = hourly average of excess combustion oxygen, in percent
HI = heat input, in million Btu per hour

(e) By the 15th day of each month, the monthly average of CO emissions in lb/hr shall be
calculated by using the hourly average CO emission values in lb/hr.

II.B.2.f.2 Recordkeeping:

Results of monitoring shall be maintained in accordance with Provision I.S.1 of this permit and
the above required testing methods.

II.B.2.f.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: Not Evaluated. Continuous monitoring requirements are evaluated by DAQ’s CEM specialist.

II.B.2.g Condition:

The permittee must operate and maintain any affected source, including associated air pollution control
equipment and monitoring equipment, in a manner consistent with safety and good air pollution control
practices for minimizing emissions, at all times. Determination of whether such operation and
maintenance procedures are being used will be based on information available to the EPA Administrator
which may include, but is not limited to, monitoring results, review of operation and maintenance
procedures, review of operation and maintenance records, and inspection of the source.
[Origin: 40 CFR 63.10000(b)]. [40 CFR 63 Subpart UUUUU]

II.B.2.g.1 Monitoring:

Records required for this permit condition will serve as monitoring.

II.B.2.g.2 Recordkeeping:

The permittee shall keep the records described in 40 CFR 63.10032(a) through (j), as applicable.
[40 CFR 63.10032]

The permittee shall document activities performed to assure proper operation and maintenance.

Records shall be maintained in accordance with 40 CFR 63.10033 and
Provision I.S.1 of this permit.

II.B.2.g.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. The facilities appeared to be well maintained. A preventative maintenance
database called Maximo is in place and utilizes a work order program to track and record all
maintenance activities.
31
II.B.2.h Condition:

(1) The permittee shall comply with the following requirements for each affected emission unit:

(a) Emission of filterable particulate matter (PM) shall be no greater than 3.0E-02 lb/MMBtu or 3.0E-1
lb/MWh;
(b) Emission of HCl shall be no greater than 2.0E-03 lb/MMBtu or 2.0E-2 lb/MWh;
(c) Emission of mercury (Hg) shall be no greater than 1.2E0 lb/TBtu or 1.3E-2 lb/GWh;
(d) The permittee shall conduct a tune-up of the EGU burner and combustion controls at least each 36
calendar months, or each 48 calendar months if neural network combustion optimization software is
employed, as specified in 40 CFR 63.10021(e);
(e) The permittee shall comply with each operating limit in Table 4 of 40 CFR 63 Subpart UUUUU for
each affected EGU at the source;
(f) The permittee shall comply the emission and operating limits at all times except during periods of
startup and shutdown as defined in 40 CFR 63.10042. The permittee shall meet the work practice in
Table 3 of 40 CFR 63 Subpart UUUUU during periods of startup, or shutdown as defined in 40 CFR
63.10042;
(g). The permittee may use emissions averaging as described in 40 CFR 63.10009 as an alternative to
meet the requirements in (1)(a) of this section for filterable PM, SO2 , HF, HCl, non-Hg HAP metals, or
Hg on an EGU-specific basis.

(2) As provided in 40 CFR 63.6(g), the Director may approve use of an alternative to the work practice
standards in this section;

(3) The permittee may use the alternate SO2 limit in Table 2 of 40 CFR 63 Subpart UUUUU only if the
affected coal-fired EGU:

(a) Has a system using wet or dry flue gas desulfurization technology and SO2 CEM installed on the unit;
and
(b) At all times, the permittee operates the wet and dry flue gas desulfurization technology installed on
the unit consistent with 40 CFR 63.10000(b)

[Origin: 40 CFR 63.9991, 63.10000(a), 63.10009, 40 CFR 63 Subpart UUUUU Tables 2(1), 3, and 4].
[40 CFR 63 Subpart UUUUU]

II.B.2.h.1 Monitoring:

The permittee shall conduct the required applicable monitoring as required in 40 CFR 63 Subpart
UUUUU.

(a) PM: The permittee shall conduct a PM performance test on quarterly basis as required in 40
CFR 63 Subpart UUUUU Tables 5(1) and 7(4), as well as in 40 CFR 63.10006(c) and (f) through
(h). If the LEE status is established for PM, the permittee shall conduct a PM performance test
once every 36 calendar months to demonstrate continued LEE status as required in 40 CFR
63.10006(b). If the LEE status is lost, the permittee shall conduct quarterly performance tests and
the LEE status may be re-established in accordance with 40 CFR 63.10005(h)(1)(i).

(b) HCl: The permittee shall conduct a HCl performance test on quarterly basis as required in 40
CFR 63 Subpart UUUUU Tables 5(3) and 7(4), as well as in 40 CFR 63.10006(d) and (f) through
(h). If the LEE status is established for HCl, the permittee shall conduct a HCl performance test
32
once every 36 calendar months to demonstrate continued LEE status as required in 40 CFR
63.10006(b). If the LEE status is lost, the permittee shall conduct quarterly performance tests and
the LEE status may be re-established in accordance with 40 CFR 63.10005(h)(1)(i).

(c) Hg: The permittee shall operate a sorbent trap monitoring, in accordance with appendix A to
40 CFR 63 Subpart UUUUU

(1) The permittee may choose to use separate sorbent trap monitoring systems to comply with the
requirement: one sorbent trap monitoring system to demonstrate compliance with the numeric
mercury emission limits during periods other than startup or shutdown and the other sorbent trap
monitoring system to report average mercury concentration during startup periods or shutdown
periods.

(2) The permittee may choose to use one sorbent trap monitoring system to demonstrate
compliance with the mercury emissions limit at all times (including startup periods and shutdown
periods) and to report average mercury concentration. The permittee must follow the startup or
shutdown requirements that follow and as given in 40 CFR 63 Subpart UUUUU Table 3(3)

(3) The permittee shall calculate and record a 30-boiler operating day rolling average Hg
emission rate, in units of the standard, updated after each new boiler operating day in accordance
with Appendix A to 40 CFR 63 Subpart UUUUU. Each 30-boiler operating day rolling average
emission rate is the average of all of the valid hourly Hg emission rates in the preceding 30 boiler
operating dates. (40 CFR 63.10010(g) and 40 CFR 63.10021(b))

(4) If the LEE status is established for Hg in accordance with 40 CFR 63.10005(h)(3), the
permittee shall conduct a Hg performance test once every year in according with Table 5 of 40
CFR 63 Subpart UUUUU and 40 CFR 63.10007. If LEE status is lost, the permittee shall follow
the procedures required in 40 CFR 63.10006(b)(2).

(d) Tune-up: The permittee shall conduct periodic performance tune-ups as specified in 40 CFR
63.10021(e)(1) through (9) and Table 3(1).

(e) The permittee shall follow the startup or shutdown requirement as given in Table 3 to 40 CFR
63 Subpart UUUUU and in 40 CFR 63 Subpart 63.10021(h)(1) through (4). [40 CFR 63 Subpart
UUUUU].

II.B.2.h.2 Recordkeeping:

(a) The permittee shall maintain the applicable records required in 40 CFR 63.10032 (a) through
(i).

(b) The permittee shall maintain applicable records, in a manner suitable for expeditious review,
for a total of 5 years following the date of each occurrence, measurement, maintenance,
corrective action, report or record.

(c) The permittee shall keep records on-site for at least 2 years after the date of each occurrence,
measurement, maintenance, corrective action, report or record. The permittee can keep the
records off site for the remaining 3 years.

(d) Records shall be maintained in accordance with Provision I.S.1 of this permit.

33
II.B.2.h.3 Reporting:

(a) The permittee shall submit a Notification of Intent to conduct a performance test at least 30
days before the performance test is scheduled to be begin (40 CFR 63.10030(d));

(b) Permittee shall submit a Notification of Compliance Status with 60 days of completing a
performance test as required in 40 CFR 63.10030(e) and 40 CFR 63.9(h)(2)(i);

(c) Unless the Director has approved a different schedule, the permittee shall submit a semiannual
compliance report at the frequency as required in 40 CFR 63.10031 (b)(1) through (5);

(d) The compliance report must contain the information required in 40 CFR 63.10031 (c)(1)
through (9);

(e) The compliance report must contain excess emission as required in 40 CFR 63.10031 (d),
deviations as required in 40 CFR 63.10031(e), and performance test reports as required in 40
CFR 63.10031(f), as applicable.

(f) The compliance report must include the number, duration, and a brief description of each type
of malfunction which occurred during the reporting period and which caused or may have caused
an applicable emission limitation to be exceeded as required in 40 CFR 63.10031(g).

Status: In Compliance. The most recent tune-up of Boiler 1 was performed on July 13, 2023. The most
recent tune-up of Boiler 2 was performed on May 12, 2022.

Intermountain Power has achieved LEE status for PM and HCl. Stack testing was last conducted
of Unit 1 on January 9-10, 2024. Test results were submitted to DAQ and audited in DAQC-154-24.
DAQ calculated results for PM were 0.0021 lb/MMBtu and for HCl were 0.0001 lb/MMBtu.

Stack testing of Unit 2 was last conducted April 17-18, 2024. Intermountain Power has 60 days
from testing to submit results to DAQ. Previously, stack testing was conducted February 11-12,
2021. Test results were submitted to DAQ and audited in DAQC-890-21. DAQ calculated results
for PM were 0.0031 lb/MMBtu and for HCl were 0.0001 lb/MMBtu. The April 2024 testing was
conducted later than 36 months from the February 2021 test. The unit had been off line for several
months prior to April 2024 and was tested upon startup.

See condition II.B.2.i below for mercury testing requirements.

II.B.2.i Condition:

Emissions of mercury shall be no greater than either 6.5x10-7 lbs/MMBtu heat input or 10% of incoming
fuel-based mercury (90% control of total mercury emissions) for each boiler based on an annual
averaging period beginning January 1 and ending December 31. [Origin: R307-424-4 (State Only
Requirement)]. [R307-424-4]

II.B.2.i.1 Monitoring:

(a) The permittee shall monitor mercury by one of the following methods:

(1) install, calibrate, maintain and operate a continuous monitoring system for measuring
emissions in accordance with Appendix A to 40 CFR 63 Subpart UUUUU,
34
(2) perform 30-day Method 30B testing following the LEE provisions of 40 CFR 63 Subpart
UUUUU, or
(3) perform such other EPA-approved stack emission testing as approved by the Director.

(b) Each continuous emission monitoring system shall meet the quality assurance requirements of
R307-170, Continuous Emission Monitoring Systems Program and Appendix A to 40 CFR 63
Subpart UUUUU. Other monitoring shall follow standard reference methodology under EPA
protocol (EPA Reference Methods) as approved by the Director.

II.B.2.i.2 Recordkeeping:

(a) If compliance is determined with a Continuous Emission Monitoring System, the permittee
shall maintain a file of 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 and maintenance performed on these systems or devices.

(b) The permittee shall maintain records of the occurrence and duration of any startup, shutdown,
or malfunction in the operation of the unit; any malfunction of the air pollution control
equipment; or any periods during which a continuous monitoring system or monitoring device is
inoperative if compliance is determined with a Continuous Emission Monitoring System.

(c) Records shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.2.i.3 Reporting:

(a) If compliance is determined with a Continuous Emission Monitoring System, the permittee
shall submit notifications and reports to the Director as required by R307-170, Continuous
Emission Monitoring Systems Program and comply with the reporting provision in Appendix A
to 40 CFR 63 Subpart UUUUU.

(b) If compliance is determined with a Continuous Emission Monitoring System, upon
completion of each year's fourth quarterly report, an assessment shall be made for the entire
calendar year and reported to the Director within 30 days.

(c) If compliance is determined with a Continuous Emission Monitoring System, the reports
required in paragraph (a) above are considered prompt notification of permit deviations required
in provision I.S.2.c of this permit if all information required by provision I.S.2.c is included in the
report.

(d) If compliance is determined with a stack testing, results of required stack testing shall be
submitted to the Director within 45 days of completion of the testing. The submittal shall clearly
identify results and indicate compliance status. The annual compliance certification required by
Provision L in Section I of this permit shall use the most recent test results as a basis for stating
compliance status for this limitation.

Status:

In Compliance. Intermountain Power has chosen option (a)(2) to demonstrate compliance. LEE
status has been achieved and annual 30-day testing is being performed. Hg testing was last
performed August 24 through September 26, 2023. Test results were submitted to DAQ and
audited in DAQC-1233-23. DAQ calculated results were 2.1x10-7 lbs/MMBtu from Unit 1 and
1.7x10-7 lbs/MMBtu from Unit 2.
35
II.B.2.j Condition:

Sulfur content of the fuel oil combusted in the main boilers shall be no greater than 0.85 lb/MMBtu heat
input. [Origin: DAQE-AN103270030-22]. [R307-203-1, R307-401-8]

II.B.2.j.1 Monitoring:

Compliance with this limitation shall be determined either by testing the fuel monthly for the
following specifications: 1) Weight Percent Sulfur 2) Gross Heating Value (Btu per unit volume)
and 3) Density; by inspection of these specifications as provided by the vendor for each delivery
of fuel; or by direct vendor certification that all deliveries have met the sulfur content limit. All
specifications shall be ascertained in accordance with methods of American Society for Testing
and Materials.

Sulfur content in lbs/MMBtu shall be determined by the following equation:

S lbs/MMBtu = [(Weight percent sulfur/100) x Density (lb/gal)] / [(gross heating value (Btu/gal))
x (1 MMBtu/1,000,000 Btu)].

II.B.2.j.2 Recordkeeping:

Results of monitoring shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.2.j.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: The permittee operates their own analytical laboratory and analyzes fuel oil and coal weekly. No
deviations of the sulfur limit have been recorded or reported for either fuel.

II.B.2.k Condition:

The permittee may fuel-blend self-generated used oil with coal at the active coal pile reclaim structure
provided that self-generated used oil has not been mixed with hazardous waste. [Origin: DAQE-
AN103270030-22]. [R307-401-8]

II.B.2.k.1 Monitoring:

Each batch of used oil shall be tested as required by UAC R315-15-1-1.2 prior to energy
recovery.

II.B.2.k.2 Recordkeeping:

The record of the contaminant character of the used oil shall be maintained in accordance with
Provision I.S.1 of this permit.

36
II.B.2.k.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. IPP is blending used oil with coal at the active coal pile reclaim structure. Used oil
is sent to American West Analytical Laboratories for testing prior to energy recovery. Records of
analysis are maintained and were made available for review. A total of 8,250 gallons were applied
on March 27, 2024. Prior to this, used oil had not been applied since March 19, 2023.

II.B.3 Conditions on Emergency Diesel Generators (EU#49).

II.B.3.a Condition:

The permittee shall not operate each emergency engine on site for more than 100 hours per rolling 12-
month period during non-emergency situations. There is no time limit on the use of the engines during
emergencies. [Origin: DAQE-AN0103270030-22]. [R307-401-8]

II.B.3.a.1 Monitoring:

The permittee shall install a non-resettable hour meter for each emergency engine. The permittee
shall calculate a new 12-month total by the 20th day of each month using data from the previous
12 months. The permittee shall calculate a new 12-month total by the 20th day of each month
using data from the previous 12 months.

II.B.3.a.2 Recordkeeping:

Records documenting the operation of each emergency engine shall be kept in a log and shall
include the following:
A. The date the emergency engine was used
B. The duration of operation in hours
C. The reason for the emergency engine usage.

Results of monitoring shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.3.a.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. These generators are typically only fired for annual opacity observations. Hour
readings have been taken and recorded weekly. Generator use logs are kept. No generator has
operated for more than 100 hours in the 12-month rolling period preceding this inspection.

II.B.3.b Condition:

Visible emissions shall be no greater than 20 percent opacity except for start-up or shutdown and except
for operation not exceeding 3 minutes in any hour. [Origin: DAQE-AN0103270030-22]. [R307-401-8]

37
II.B.3.b.1 Monitoring:

Opacity observations of emissions shall be conducted annually in accordance with 40 CFR
Part 60, Appendix A, Method 9.

II.B.3.b.2 Recordkeeping:

Results of monitoring shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.3.b.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. Annual opacity observations have been performed and recorded.

II.B.3.c Condition:

The permittee shall only use diesel fuel (e.g. fuel oil #1, #2, or diesel fuel oil additives) as fuel in each
emergency engine and shall only combust diesel fuel that meets the definition of ultra-low sulfur diesel
(ULSD), which has a sulfur content of 15 ppm or less. [Origin: DAQE-AN103270030-22]. [R307-401-8]

II.B.3.c.1 Monitoring:

The permittee shall maintain records of diesel fuel purchase invoices or obtain certification of
sulfur content from the diesel fuel supplier. The diesel fuel purchase invoices shall indicate that
the diesel fuel meets the ULSD requirements.

II.B.3.c.2 Recordkeeping:

Results of monitoring shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.3.c.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. Only USLD is burned. Intermountain Power rarely fires these engines and hasn’t
purchased fuel in several years.

II.B.4 Conditions on Emergency Fire Pumps (EU #77)

II.B.4.a Condition:

The permittee shall not operate each emergency engine on site for more than 100 hours per rolling 12-
month period during non-emergency situations. There is no time limit on the use of the engines during
emergencies. [Origin: DAQE-AN0103270030-22]. [R307-401-8]

38
II.B.4.a.1 Monitoring:

The permittee shall install a non-resettable hour meter for each emergency engine. The permittee
shall calculate a new 12-month total by the 20th day of each month using data from the previous
12 months.

II.B.4.a.2 Recordkeeping:

Records documenting the operation of each emergency engine shall be kept in a log and shall
include the following:
A. The date the emergency engine was used
B. The duration of operation in hours
C. The reason for the emergency engine usage.

Results of monitoring shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.4.a.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. Hour readings have been taken and recorded weekly. Generator use logs are kept.
No generator has operated for more than 100 hours in the 12-month rolling period preceding this
inspection.

II.B.4.b Condition:

Visible emissions shall be no greater than 20 percent opacity except for start-up or shutdown and except
for operation not exceeding 3 minutes in any hour. [Origin: DAQE-AN0103270030-22]. [R307-401-8]

II.B.4.b.1 Monitoring:

Opacity observation of emissions shall be conducted annually in accordance with 40 CFR 60,
Appendix A, Method 9.

II.B.4.b.2 Recordkeeping:

Results of monitoring shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.4.b.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. Opacity observations have been performed and recorded annually.

39
II.B.4.c Condition:

At all times the permittee shall operate and maintain any affected source, including
associated air pollution control equipment and monitoring equipment, in a manner consistent with safety
and good air pollution control practices for minimizing emissions. The general duty to minimize
emissions does not require the permittee to make any further efforts to reduce emissions if levels required
by this standard have been achieved. Determination of whether such operation and maintenance
procedures are being used will be based on information available to the Director which may
include, but is not limited to, monitoring results, review of operation and maintenance procedures, review
of operation and maintenance records, and inspection of the source.
[40 CFR 63.6595(a)(1), 40 CFR 63.6605(b)]. [40 CFR 63 Subpart ZZZZ]

II.B.4.c.1 Monitoring:

Records required for this permit condition will serve as monitoring. [40 CFR 63 Subpart ZZZZ]

II.B.4.c.2 Recordkeeping:

The permittee shall keep the records described in 40 CFR 63.6655(a)(1)-(5) as applicable.
[40 CFR 63.6655(a)]
The permittee shall document activities performed to assure proper operation
and maintenance. Records shall be maintained in accordance with 40 CFR 63.6660 and
Provision I.S.1 of this permit.

II.B.4.c.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. The facilities appeared to be well maintained. A preventative maintenance
database called Maximo is in place and utilizes a work order program to track and record all
maintenance activities.

II.B.4.d Condition:

The permittee shall comply with the following operating limitations at all times for each
emergency affected emission unit:

(1) The permittee shall operate the affected emission unit according to the requirements in 40 CFR
63.6640(f)(1) through (4). Any operation other than emergency operation, maintenance and testing,
emergency demand response, and operation in non-emergency situations for 50 hours per year,
paragraphs 40 CFR 63.6640(f)(1) through (4), is prohibited. If the engine is not operated in accordance
with paragraphs 40 CFR 63.6640(f)(1) through (4), it will not be considered an emergency engine and
shall meet all requirements for non-emergency engines.

(2) The permittee shall meet the following requirements at all times, except during periods of startup:

(a) Change oil and filter every 500 hours of operation or annually, whichever comes first, except as
otherwise provided under II.B.4.d.(2)(d);

(b) Inspect air cleaner every 1,000 hours of operation or annually, whichever comes first;
40
(c) Inspect all hoses and belts every 500 hours of operation or annually, whichever comes first, and
replace as necessary;

(d) The permittee may opt to perform oil analysis procedures as outlined in 40 CFR 63 .6625(i) or (j) in
order to extend the specified oil change requirement found at II.B.4.d.(2)(a).

(3) During periods of startup, the permittee shall minimize the engine's time spent at idle and minimize
the engine's startup time to a period needed for appropriate and safe loading of the engine, not to
exceed 30 minutes, after which time the non-startup emission limitations apply.

(4) The permittee shall comply with the applicable general provisions in 40 CFR 63.1-15 as identified in
Table 8 of 40 CFR 63 Subpart ZZZZ.

[40 CFR 63.6595(a)(1), 40 CFR 63.6602, 40 CFR 63.6605(a), 40
CFR 63.6625(h), 40 CFR 63.6640(f), 40 CFR 63.6665, 40 CFR 63 Subpart ZZZZ Table 2c, 40 CFR 63
Subpart ZZZZ Table 8]. [40 CFR 63 Subpart ZZZZ]

II.B.4.d.1 Monitoring:

The permittee shall install a non-resettable hour meter if one is not already installed.
[40 CFR 63.6625(f)]

If an emergency engine is operating during an emergency and it is not possible to shut down the
engine in order to perform the work practice requirements on the required schedule, or if
performing the work practice on the required schedule would otherwise pose an unacceptable risk
under Federal, State, or local law, the work practice can be delayed until the emergency is over or
the unacceptable risk under Federal, State, or local law has abated. The work practice shall be
performed as soon as practicable after the emergency has ended or the unacceptable risk under
Federal, State, or local law has abated. [40 CFR 63 Subpart ZZZZ Table 2c Footnote 1]

The permittee shall demonstrate continuous compliance by operating and maintaining the
stationary RICE and after-treatment control device (if any) according to the manufacturer's
emission-related written operation and maintenance instructions or develop and follow their own
maintenance plan which must provide to the extent practicable for the maintenance and operation
of the engine in a manner consistent with good air pollution control practice for minimizing
emissions. [40 CFR 63.6625(e), 40 CFR 63.6640(a), 40 CFR 63 Subpart ZZZZ Table 6]

The permittee has the option of utilizing an oil analysis program in order to extend the specified
oil change requirement in accordance with 40 CFR 63.6625(i).
The permittee shall comply with the applicable general provisions in 40 CFR 63.1-15 as
identified in Table 8 of 40 CFR 63 Subpart ZZZZ. [40 CFR 63.6665].

II.B.4.d.2 Recordkeeping:

The permittee shall keep the records described in 40 CFR 63.6655(a)(1)-(5) as applicable. [40
CFR 63.6655(a)]

For each affected emission unit that does not meet the standards applicable to non-emergency
engines, the permittee shall keep records of the hours of operation of the engine that are recorded
through the non-resettable hour meter. The permittee shall document how many hours are spent
for emergency operation, including what classified the operation as emergency and how many
41
hours are spent for non-emergency operation. If the engines are used for demand response
operation, the permittee shall keep records of the notification of the emergency situation, and the
time the engine was operated as part of demand response. [40 CFR 63.6655(f)]

If additional hours are to be used for maintenance checks and readiness testing, the permittee
shall maintain records indicating that Federal, State, or local standards require maintenance and
testing of emergency RICE beyond 100 hours per year. [40 CFR 63.6640(f)(1)(ii)]

The permittee shall keep records that demonstrate continuous compliance with each applicable
operating limitation [including, but not limited to, the manufacturer's emission-related operation
and maintenance instructions or the permittee-developed maintenance plan]. [40 CFR 63.6655(d),
40 CFR 63 Subpart ZZZZ Table 6]

Records of the maintenance conducted shall be kept in order to demonstrate that the permittee
operated and maintained the affected emission unit and after-treatment control device (if any)
according to their own maintenance plan. [40 CFR 63.6655(e)]

The permittee shall comply with the applicable general provisions in 40 CFR 63.1-15 as
identified in Table 8 of 40 CFR 63 Subpart ZZZZ. [40 CFR 63.6665].

Records shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.4.d.3 Reporting:

The permittee shall report any failure to perform the work practice on the schedule required and
the Federal, State or local law under which the risk was deemed unacceptable.
[40 CFR 63 Subpart ZZZZ Table 2c Footnote 1]

The permittee shall comply with the applicable general provisions in 40 CFR 63.1-15 as
identified in 40 CFR 63 Subpart ZZZZ Table 8. [40 CFR 63.6665] The permittee shall also
report each instance in which it did not meet the applicable requirements in Table 8.
[40 CFR 63.6640(e)]

There are no additional reporting requirements for this provision except those specified in Section
I of this permit.

Status: In Compliance. The facilities appeared to be well maintained. A preventative maintenance
database called Maximo is in place and utilizes a work order program to track and record all
maintenance activities. Maintenance required by this condition has been included.

These engines are rarely fired, and no engine has operated in excess of the 50 hour limit for non-
emergency purposes.

II.B.4.e Condition:

The permittee shall only use diesel fuel (e.g. fuel oil #1, #2, or diesel fuel oil additives) as fuel in each
emergency fire pump and shall only combust diesel fuel that meets the definition of ultra-low sulfur
diesel (ULSD), which has a sulfur content of 15 ppm or less. [Origin: DAQE-AN103270030-22].
[R307-401-8]

42
II.B.4.e.1 Monitoring:

The permittee shall maintain records of diesel fuel purchase invoices or obtain certification of
sulfur content from the diesel fuel supplier. The diesel fuel purchase invoices shall indicate that
the diesel fuel meets the ULSD requirements.

II.B.4.e.2 Recordkeeping:

Results of monitoring shall be maintained in accordance with Provision I.S.1 of this permit.

II.B.4.e.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. Only USLD is burned. Intermountain Power rarely fires these engines and hasn’t
purchased fuel in several years.

II.B.5 Conditions on Coal Conveyers (EU #58).

II.B.5.a Condition:

Visible emissions shall be no greater than 20 percent opacity. [Origin: DAQE-AN0103270030-22].
[40 CFR 60 Subpart Y, R307-401-8]

II.B.5.a.1 Monitoring:

A visual observation of each affected emission unit shall be performed once each month that the
unit operates, by an individual trained on the observation procedures of 40 CFR 60, Appendix A,
Method 9. The individual is not required to be a certified visible emissions observer (VEO). If
any visible emissions are observed, an opacity determination of that emission unit shall be
performed by a certified VEO in accordance with 40 CFR 60, Appendix A, Method 9 within 24
hours of the initial observation.

II.B.5.a.2 Recordkeeping:

A log of opacity observations shall be maintained in accordance with Provision I.S.1 of this
permit. If an observation indicates visible emissions, a notation of those visible emissions shall
be made in the log. All data required by 40 CFR 60, Appendix A, Method 9 shall also be
maintained in accordance with Provision I.S.1 of this permit.

II.B.5.a.3 Reporting:

There are no reporting requirements for this provision except those specified in Section I of this
permit.

Status: In Compliance. Coal conveyors are covered. Visible observations are conducted and recorded
monthly. Coal conveyers were surveyed during this inspection and no fugitive emissions were
observed.

43
II.B.6 Conditions on Dust Collector Group 1 (EU #Group 1).

II.B.6.a Condition:

Except for times of start-up, shut-down, or malfunction, differential pressure at the indicated emission
points, at all times, shall be no greater than 12 inches of water gage and no less than 0.5 inches of water
gage. I f differential pressure is in the 0.5 to 2, or 10 to 12 range, a work order shall be written to
investigate. Dust collector may run in the 0.5 to 2 or 10 to 12 range if a reason is known
[Origin: DAQE-AN103270030-22]. [R307-401-8]

II.B.6.a.1 Monitoring:

(a) Measurement Approach: The permittee shall check the pressure drop across the baghouse or
to atmosphere (whichever is specified by the manufacture) to make sure that the pressure drop is
in the range.

(b) Indicator Range: An excursion is defined as a pressure drop less than 0.5 and greater than 12
in. H2O. Excursions trigger an inspection, corrective action, and a reporting requirement.

(c) Performance Criteria:

(1) Data Representativeness: Pressure taps shall be located at the dust collector inlet and outlet.
The gauge has a minimum accuracy of 0.25 in. H2O.

(2) QA/QC Practices and Criteria: The pressure gauge shall be calibrated annually.

(3) Monitoring Frequency: Differential pressure shall be measured continuously during
operation.

(4) Data Collection Procedure: Pressure drop shall be manually recorded monthly. (40 CFR
64.3).

II.B.6.a.2 Recordkeeping:

In addition to the recordkeeping requirement described in Provision I.S.1 of this permit, the
permittee shall maintain a file of the occurrence and duration of any excursion, corrective actions
taken, and any other supporting information required to be maintained under 40 CFR 64 (such as
data used to document the adequacy of monitoring, or records of monitoring maintenance or
corrective actions). Instead of paper records, the permittee may maintain 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 inspection and review, and does not conflict
with other applicable recordkeeping requirements. (40 CFR 64.9(b)).

44
II.B.6.a.3 Reporting:

In addition to the reporting requirement described in Provision I.S.2 of this permit, the monitoring
report shall include, at a minimum, the following information, as applicable:

(a) Summary information on the number, duration and cause (including unknown cause, if
applicable) of excursions or exceedances, as applicable, and the corrective actions taken;(40 CFR
64.9(a)(2)(i))

(b) Summary information on the number, duration and cause (including unknown cause, if
applicable) for monitor downtime incidents (other than downtime associated with zero and span
or other daily calibration checks, if applicable). (40 CFR 64.9(a)(2)(ii))

Status: In Compliance. The pressure drop on each baghouse is manually checked and recorded monthly.
Records indicated no excursions occurred during the prior 12 months. The pressure gauges have
been calibrated annually. In addition, a quarterly inspection and maintenance program is in place
and recorded. Excursions are reported with semi-annual monitoring reports.

II.B.6.b Condition:

Visible emissions shall be no greater than 20 percent opacity. [Origin: DAQE-AN0103270030-22].
[R307-401-8]

II.B.6.b.1 Monitoring:

(a) Measurement Approach: A visual observation of each affected unit shall be made at least
once each day using 40 CFR Part 60, Appendix A, Reference Method 22-like procedures.

(b) Indicator Range: An excursion is defined as the presence of visible emissions. If visible
emissions are noted, a Method 9 VEO shall be conducted to determine the percent opacity or
maintenance shall be performed on the affected unit to correct the problem.

(c) Performance Criteria:

(1) Data Representativeness: A visual observation shall be made in a facility-wide scan to
observe each applicable emission point.

(2) QA/QC Practices and Criteria: The observer shall be familiar with Reference Method 22 and
follow Method 22-like procedures.

(3) Monitoring Frequency: A facility-wide Method 22-like observation shall be performed daily,
of sufficient duration for all applicable dust collectors.

(4) Data Collection Procedure: The observation shall be documented by the observer. If
emissions are visible, subsequent action shall be noted.

45
II.B.6.b.2 Recordkeeping:

In addition to the recordkeeping requirement described in Provision I.S.1 of this permit, the
permittee shall maintain a file of the occurrence and duration of any excursion, corrective actions
taken, and any other supporting information required to be maintained under 40 CFR 64 (such as
data used to document the adequacy of monitoring, or records of monitoring maintenance or
corrective actions). Instead of paper records, the permittee may maintain 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 inspection and review, and does not conflict
with other applicable recordkeeping requirements. (40 CFR 64.9(b)).

II.B.6.b.3 Reporting:

In addition to the reporting requirement described in Provision I.S.2 of this permit, the monitoring
report shall include, at a minimum, the following information, as applicable:

(a) Summary information on the number, duration and cause (including unknown cause, if
applicable) of excursions or exceedances, as applicable, and the corrective actions taken; (40 CFR
64.9(a)(2)(i))

(b) Summary information on the number, duration and cause (including unknown cause, if
applicable) for monitor downtime incidents (other than downtime associated with zero and span
or other daily calibration checks, if applicable). (40 CFR 64.9(a)(2)(ii)).

Status: In Compliance. VEOs are conducted every day using Method 22-like procedures and recorded. No
visible emissions were observed coming from dust collectors during this inspection.

II.B.7 Conditions on Dust Collector Group 2 (EU #Group 2).

II.B.7.a Condition:

Visible emissions shall be no greater than 20 percent opacity. [Origin: DAQE-AN0103270030-22].
[R307-401-8]

II.B.7.a.1 Monitoring:

(a) Measurement Approach: A visual observation of each affected unit shall be made at least
once each day using 40 CFR Part 60, Appendix A, Reference Method 22-like procedures.

(b) Indicator Range: An excursion is defined as the presence of visible emissions. If visible
emissions are noted, a Method 9 VEO shall be conducted to determine the percent opacity or
maintenance shall be performed on the affected unit to correct the problem.

(c) Performance Criteria:

(1) Data Representativeness: A visual observation shall be made in a facility-wide scan to
observe each applicable emission point.

(2) QA/QC Practices and Criteria: The observer shall be familiar with Reference Method 22 and
follow Method 22-like procedures.

46
(3) Monitoring Frequency: A facility-wide Method 22-like observation shall be performed daily,
of sufficient duration for all applicable dust collectors.

(4) Data Collection Procedure: The observation shall be documented by the observer. If
emissions are visible, subsequent action shall be noted.

II.B.7.a.2 Recordkeeping:

In addition to the recordkeeping requirement described in Provision I.S.1 of this permit, the
permittee shall maintain a file of the occurrence and duration of any excursion, corrective actions
taken, and any other supporting information required to be maintained under 40 CFR 64 (such as
data used to document the adequacy of monitoring, or records of monitoring maintenance or
corrective actions). Instead of paper records, the permittee may maintain 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 inspection and review, and does not conflict
with other applicable recordkeeping requirements. (40 CFR 64.9(b)).

II.B.7.a.3 Reporting:

In addition to the reporting requirement described in Provision I.S.2 of this permit, the monitoring
report shall include, at a minimum, the following information, as applicable:

(a) Summary information on the number, duration and cause (including unknown cause, if
applicable) of excursions or exceedances, as applicable, and the corrective actions taken; (40 CFR
64.9(a)(2)(i))

(b) Summary information on the number, duration and cause (including unknown cause, if
applicable) for monitor downtime incidents (other than downtime associated with zero and span
or other daily calibration checks, if applicable). (40 CFR 64.9(a)(2)(ii)).

Status: In Compliance. VEOs are conducted every day using Method 22-like procedures and recorded. No
visible emissions were observed coming from dust collectors during this inspection.

II.C Emissions Trading.

Not applicable to this source.

II.D Alternative Operating Scenarios.

Not applicable to this source.

II.E Source-specific Definitions.

The following definitions apply to the permittee. They include terms not defined in state or federal rules
or clarify or expand on existing definitions.

II.E.1 Startup. Startup begins when the forced draft fans are turned on with the intent to bring the unit on line to
generate power and ends when the baghouse is in service. Startup of the baghouse must begin
immediately when the inlet temperature(s) of the baghouse(s) reach 210oF and less than 10 percent of the
boiler's heat input is being furnished by fuel oil.

47
II.E.2 Shutdown. Shutdown begins when the load is reduced with the intent of bringing the unit off line and
ends when the fuel and forced draft fans are turned off.

II.E.3 Downtime. Downtime is that time between the end of shutdown and the beginning of startup.

II.E.4 Maintenance Outage. The removal of a unit from service availability to perform work on specific
components that can be deferred beyond the end of the next weekend, but requires the equipment be
removed from service before the next planned outage. Typically, a Maintenance Outage may occur
anytime during the year, have a flexible start date, and may or may not have a predetermined duration.

II.E.5 Planned Outage. The removal of a unit from service availability for inspection and/or general overhaul of
one or more major equipment groups. This outage usually is scheduled well in advance.

EMISSION INVENTORY: The following was taken from DAQ’s 2022 emissions inventory
report (in tons/year):

PM10: 696.48
PM2.5: 648.58
SOx: 1,666.92
NOx: 7701.23
CO: 623.07
VOC: 74.94

PREVIOUS ENFORCEMENT
ACTIONS: None within the previous five years.

COMPLIANCE STATUS &
RECOMMENDATIONS: In Compliance with the conditions of Title V Operating Permit
2700010006 evaluated above.

HPV STATUS: Not Applicable.

COMPLIANCE
ASSISTANCE: None required.

RECOMMENDATION FOR
NEXT INSPECTION: Inspect as usual.

ATTACHMENT: VEO Form, status of construction notification

I ntermountain Power Service Corporation
November 7,2022
Mr. Bryce Bird, Director
Utah Division of Air QualitY
NSR Section
P.O. Box L4482O
Salt Lake City, Utah 84LL4-482O
Vio Emoiland Stondord Moil
Dear Director Bird:
IPP Renewal Project Status of Construction
pursuant to Approval Order DAQE-AN10327OO29-22, lntermountain Power Service Corporation ("lPSC")
is providing the Utah Division of Air Quality (UDAq with its "status of construction" notice for the IPP
Renewal Project. On October 14, IPA commenced construction on its new natural gas fired electricity
generating unit facility. This letter also serves as IPSC's notice under the Utah Administrative Code
("UAC") R3O7-401-18 that IPA has begun a continuous program of construction for the IPP Renewal
Project.
ln addition, the Project is subject to the notification requirements set forth in the New Source
performance Standards (NSPS), General Provisions 40 CFR 60.7(aX1). This letter serves as notice to
UDAQ and to the Environmental Protection Agency (EPA) that IPSC commenced construction on October
14,2022. After construction is completed, the turbine under construction will be subject to the
following NSPS:
o NSpS (part 60), Da: Standards of Performance for Electric Utility Steam Generating Units for Which
Construction is Commenced After September L8, L978
o NSPS (Part 50), KKKK: Standards of Performance for Stationary Combustion Turbines
o NSpS (Part 60), TTTT: Standards of Performance for Greenhouse Gas Emissions for Electric
Generating Units
lf you have any questions or comments, please contact Mr. Mike Utley, IPSC's Environmental Engineer,
at [phone], or [e-mail].
Sincerely,
/4* Zle L rr+F
Jon A. Finlinson
President and Chief Operations Officer
$f.ffiY/Hst:he
850 West Brush Wellman Road, Delta, Utah,84624 /Telephone: [phone] / F!.J.:14351 864-6670 / Fed. l.D. #87-0388573