DAQ-2024-008607

DAQE-AN157060004-24

{{$d1 }}

Cobi Lane
Duncan Aviation, Incorporated
262 South 3800 West
Provo, UT 84601
[e-mail]

Dear Mr. Lane:

Re: Approval Order: Administrative Amendment to Approval Order DAQE-AN157060003-20 to
Correct Order of Conditions
Project Number: N157060004

The attached Approval Order (AO) is issued pursuant to the Division of Air Quality conducting
an administrative amendment of this source and its respective AO. Duncan Aviation, Incorporated
must comply with the requirements of this AO, all applicable state requirements (R307), and Federal
Standards.

The project engineer for this action is Christine Bodell, who can be contacted at [phone] or
[e-mail]. Future correspondence on this AO should include the engineer's name as well as the
DAQE number shown on the upper right-hand corner of this letter. No public comments were received on
this action.

Sincerely,

{{$s }}

Bryce C. Bird
Director

BCB:CB:jg

cc: Utah County Health Department

195 North 1950 West • Salt Lake City, UT
Mailing Address: P.O. Box 144820 • Salt Lake City, UT 84114-4820
Telephone [phone] • Fax [phone] • T.D.D. [phone]
www.deq.utah.gov
Printed on 100% recycled paper
State of Utah

SPENCER J. COX
Governor

DEIDRE HENDERSON
Lieutenant Governor

Department of
Environmental Quality

Kimberly D. Shelley
Executive Director

DIVISION OF AIR QUALITY
Bryce C. Bird
Director

June 20, 2024

STATE OF UTAH
Department of Environmental Quality
Division of Air Quality

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APPROVAL ORDER
DAQE-AN157060004-24
Administrative Amendment to Approval Order
DAQE-AN157060003-20 to Correct Order of Conditions

Prepared By
Christine Bodell, Engineer
[phone]
[e-mail]

Issued to
Duncan Aviation, Incorporated - Aircraft Maintenance, Repair, and Overhaul
(MRO) Complex

Issued On
{{$d2 }}

Issued By

{{$s }}

Bryce C. Bird
Director
Division of Air Quality
June 20, 2024

TABLE OF CONTENTS

TITLE/SIGNATURE PAGE ....................................................................................................... 1
GENERAL INFORMATION ...................................................................................................... 3
CONTACT/LOCATION INFORMATION ............................................................................... 3
SOURCE INFORMATION ........................................................................................................ 3
General Description ................................................................................................................ 3
NSR Classification .................................................................................................................. 3
Source Classification .............................................................................................................. 3
Applicable Federal Standards ................................................................................................. 4
Project Description.................................................................................................................. 4
SUMMARY OF EMISSIONS .................................................................................................... 4
SECTION I: GENERAL PROVISIONS .................................................................................... 5
SECTION II: PERMITTED EQUIPMENT .............................................................................. 5
SECTION II: SPECIAL PROVISIONS ..................................................................................... 7
PERMIT HISTORY ................................................................................................................... 11
ACRONYMS ............................................................................................................................... 12

DAQE-AN157060004-24
Page 3

GENERAL INFORMATION

CONTACT/LOCATION INFORMATION

Owner Name Source Name
Duncan Aviation, Incorporated Duncan Aviation, Incorporated - Aircraft
Maintenance, Repair, and Overhaul (MRO)
Complex

Mailing Address Physical Address
262 South 3800 West 262 South 3800 West
Provo, UT 84601 Provo, UT 84601

Source Contact UTM Coordinates
Name: Cobi Lane 438,136 m Easting
Phone: [phone],453,558 m Northing
Email: [e-mail] Datum NAD83
UTM Zone 12

SIC code 4581 (Airports, Flying Fields, & Airport Terminal Services)

SOURCE INFORMATION
General Description
Duncan Aviation, Incorporated is an aircraft maintenance, repair, and overhaul site. The site operations
include airframe maintenance, aircraft on ground (AOG) emergency, avionics installation, interior and
paint refurbishment, and other engineering services. Emissions on site are generated through stripping,
sanding, painting, and detail work on the interior and exterior of aircraft. The on-site fuel storage tanks
will also contribute to source emissions.

Eleven (11) small booths, in a separate building, are used for painting, finishes, cabinetry, upholstery,
completions, and structural processes. Filters, air recirculation, and High-Volume, Low-Pressure (HVLP)
spray guns control emissions in the booths. Duncan Aviation, Incorporated operates two (2) paint hangar
bays and sixteen (16) small operation booths consisting of painting, sanding, and gluing. Aircraft will be
parked in the hangar, where a stripping solution depaints the aircraft. Once the aircraft is depainted, it is
primed, painted, and allowed to air-dry in the hangar. The hangars are controlled via a crossdraft and
downdraft system.

NSR Classification
Administrative Amendment
Source Classification
Located in Southern Wasatch Front O3 NAA, Provo UT PM2.5 NAA
Utah County
Airs Source Size: B

DAQE-AN157060004-24
Page 4

Applicable Federal Standards
MACT (Part 63), A: General Provisions
MACT (Part 63), CCCCCC: National Emission Standards for Hazardous Air Pollutants for
Source Category: Gasoline Dispensing Facilities
MACT (Part 63), HHHHHH: National Emission Standards for Hazardous Air Pollutants: Paint
Stripping and Miscellaneous Surface Coating Operations at Area Sources

Project Description
This administrative amendment is to Approval Order DAQE-AN157060003-20, dated November 12,
2020. In Section II.B (Requirements and Limitations) of the AO, the conditions are listed out of order. A
new Approval Order will be issued to correct the minor administrative error and incorporate updated
language and formatting. No changes to equipment or emissions are being made.

SUMMARY OF EMISSIONS

The emissions listed below are an estimate of the total potential emissions from the source. Some
rounding of emissions is possible.

Criteria Pollutant Change (TPY) Total (TPY)
CO2 Equivalent 0 7126.90
Carbon Monoxide 0 4.73
Nitrogen Oxides 0 4.38
Particulate Matter - PM10 0 0.66
Particulate Matter - PM2.5 0 0.66
Sulfur Dioxide 0 0.09
Volatile Organic Compounds 0 32.02

Hazardous Air Pollutant Change (lbs/yr) Total (lbs/yr)
Ethyl Benzene (CAS #100414) 0 520
Ethylene Glycol (CAS #107211) 0 900
Generic HAPs (CAS #GHAPS) 0 480
Glycol Ethers (CAS #EDF109) 0 1040
Hexane (CAS #110543) 0 1660
Methyl Isobutyl Ketone (Hexone) (CAS #108101) 0 1400
Toluene (CAS #108883) 0 2740
Xylenes (Isomers And Mixture) (CAS #1330207) 0 2520
Change (TPY) Total (TPY)
Total HAPs 0 5.63

DAQE-AN157060004-24
Page 5

SECTION I: GENERAL PROVISIONS

I.1 All definitions, terms, abbreviations, and references used in this AO conform to those used in
the UAC R307 and 40 CFR. Unless noted otherwise, references cited in these AO conditions
refer to those rules. [R307-101]

I.2 The limits set forth in this AO shall not be exceeded without prior approval. [R307-401]

I.3 Modifications to the equipment or processes approved by this AO that could affect the
emissions covered by this AO must be reviewed and approved. [R307-401-1]

I.4 All records referenced in this AO or in other applicable rules, which are required to be kept by
the owner/operator, shall be made available to the Director or Director's representative upon
request, and the records shall include the two-year period prior to the date of the request.
Unless otherwise specified in this AO or in other applicable state and federal rules, records
shall be kept for a minimum of two (2) years. [R307-401-8]

I.5 At all times, including periods of startup, shutdown, and malfunction, owners and operators
shall, to the extent practicable, maintain and operate any equipment approved under this AO,
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. All maintenance
performed on equipment authorized by this AO shall be recorded. [R307-401-4]

I.6 The owner/operator shall comply with UAC R307-107. General Requirements: Breakdowns.
[R307-107]

I.7 The owner/operator shall comply with UAC R307-150 Series. Emission Inventories.
[R307-150]

SECTION II: PERMITTED EQUIPMENT

II.A THE APPROVED EQUIPMENT

II.A.1 Duncan Aviation
Aircraft Maintenance, Repair, and Overhaul Complex

II.A.2 Two (2) Paint Bays
Downdraft Paint Bay: PPH1
Control: RTO, 3-stage particulate filters, downdraft ventilation
Total Volume: 250,000 CFM

Crossdraft Paint Bays: PPH2
Control: RTO, 3-stage filters, cross-draft ventilation
Total Volume: 150,000 CFM

MACT Applicability: Subpart HHHHHH

DAQE-AN157060004-24
Page 6

II.A.3 Small Booths: Six (6) Paint Booths
Booths:
(1) PPTPB1
(2) PACPB1
(3) PFNPB1
(4) PUPPB1
(5) PITPB1
(6) PVSPB1

Controls:
3-stage particulate filters (control efficiency: 99%)
Full roof and four (4) walls or within an enclosed room
HVLP, or electrostatic spray gun paint application

MACT Applicability: Subpart HHHHHH

II.A.4 Small Booths: Two (2) Paint Booths
(1) PFNPB3
(2) PFNPB2

Controls:
Single-stage particulate filters (control efficiency: 99%)
Full roof and four (4) walls or within an enclosed room
HVLP, or electrostatic spray gun paint application

MACT Applicability: None

II.A.5 Sanding Operations
Tables (all tables and controls vent internally):
(1) Finish Shop
(2) Structures Shop
(3) Interior Completions
(4) Building 2
(5) Upholstery

Additional controls:
Downdraft table with filters and dust collectors
MACT Applicability: Subpart HHHHHH

II.A.6 Small Booths: Three (3) Glue Booths
Booths:
(1) PCBGB1
(2) PUPGB1
(3) PITGB1

Controls:
Negative pressure air system
Two-stage particulate filter

MACT Applicability: Subpart HHHHHH

II.A.7 Concentrator Regenerative Thermal Oxidizer (RTO)
Fuel: Natural Gas
Includes: Emergency Bypass
Maximum Rating: 10.5 MMBtu/hr

DAQE-AN157060004-24
Page 7

II.A.8 Spray Guns
Style: HVLP or electrostatic

II.A.9 Three (3) Storage Tanks
Fuel: Jet Fuel
Maximum Capacity: 30,000 gallons each
MACT and NSPS Applicability: None

II.A.10 Storage Tanks
Fuel: Diesel and Unleaded Gas
Maximum Capacity: Equal to or less than 600 gallons each
MACT Applicability: Subpart CCCCCC

II.A.11 Miscellaneous Equipment
Four (4) Boilers
Fuel: Natural Gas
Maximum Rating: < 5 MMBtu/hr, each
MACT and NSPS Applicability: None

One (1) Wastewater Evaporator
Fuel: Natural Gas
Maximum Rating: < 5 MMBtu/hr
MACT and NSPS Applicability: None

SECTION II: SPECIAL PROVISIONS

II.B REQUIREMENTS AND LIMITATIONS

II.B.1 Site wide Limits and Requirements
II.B.1.a Unless otherwise specified in this AO, the owner/operator shall not allow visible emissions to
exceed 20% opacity. [R307-401-8]

II.B.1.a.1 Opacity observations of emissions from stationary sources shall be conducted in accordance with
40 CFR 60, Appendix A, Method 9. [R307-401-8]

DAQE-AN157060004-24
Page 8

II.B.1.b The owner/operator shall not allow plant-wide emissions of VOCs and HAPs from the paint
hangers and painting, sanding, finishing, and glue booths to exceed the following values:

A. 32.02 tons per rolling 12-month period for VOCs.

B. 0.83 tons per rolling 12-month period for Hexane.

C. 1.37 tons per rolling 12-month period for Toluene.

D. 1.26 tons per rolling 12-month period for Xylene.

E. 0.70 tons per rolling 12-month period for Methyl Isobutyl Ketone.

F. 0.52 tons per rolling 12-month period for Glycol Ether.

G. 0.09 tons per rolling 12-month period for Chromium.

H. 1720 pounds (0.86 tons) per rolling 12-month period for all other cumulative
HAPs.

[R307-401-8]

II.B.1.b.1 The owner/operator shall calculate a new 12-month total by the 20th day of each month using
data from the previous 12 months. The owner/operator shall use a mass-balance method to
calculate emissions from evaporative sources. The owner/operator may use the following
equations with applicable units to comply with the mass-balance method:

VOC = (% VOC by Weight)/100 x [Density (lb/gal)] x Gal Consumed x 1 ton/2000 lb x EF*

HAP = (% HAP by Weight)/100 x [Density (lb/gal)] x Gal Consumed x 1 ton/2000 lb x EF*

* EF is the applicable emission factor provided on the manufacture’s SDS sheet.

When the RTO is used for emission reductions, the owner/operator may use the following
equations to determine emission totals after control:

VOCs = [VOCs determined by mass-balance method] x [1 - 85%].

HAPs = [HAPs determined by mass-balance method] x [1 - 85%].

[R307-401-8]

II.B.1.b.2 The owner/operator shall use a mass-balance method to quantify any amount of VOCs and
HAP(s) reclaimed. The owner/operator shall subtract the amount of VOCs and HAP(s) reclaimed
from the quantities calculated above to provide the monthly total emissions of VOCs and HAPs.
[R307-401-8]

DAQE-AN157060004-24
Page 9

II.B.1.b.3 The owner/operator shall keep records of each month of the following for each material used:

A. Name of the VOC- and HAPs- emitting material, such as: paint, adhesive,
solvent, thinner, reducers, chemical compounds, toxics, isocyanates, etc.

B. Density of each material used (pounds per gallon).

C. Percent by weight of all VOC and HAP in each material used.

D. Gallons of each VOC- and HAP- emitting material used.

E. The applicable EF provided on the manufacture SDS sheet of each material
used.

F. The amount of VOC and HAP emitted by each material used.

G. The amount of VOC and HAP reclaimed from each material used.

H. The total amount of VOCs and/or HAP emitted monthly from all materials used.

[R307-401-8]

II.B.1.c Except when in use, the owner/operator shall store VOC/HAPs-containing materials and
VOC/HAPs-laden rags in covered containers. [R307-355-7, R307-401-8]

II.B.2 Small Booths Requirements
II.B.2.a The owner/operator shall ensure each small booth is equipped with a set of paint arrestor
particulate filters, or equivalent, to control particulate emissions. All air exiting small booths
shall pass through this control system before being vented to the atmosphere (outside
building/operation). [R307-401-8]

II.B.2.b The owner/operator shall not allow visible emissions from small booth operations to exceed 10%
opacity. [R307-401-8]

II.B.3 Tank Requirements
II.B.3.a The owner/operator shall operate and maintain all tanks in accordance with the manufacturer's
instructions. [R307-401-8]

II.B.4 Paint Requirements
II.B.4.a The owner/operator shall route all primers and topcoats, defined below, through the RTO once
use meets or exceeds 200 gallons per rolling 12-month period:

A. Primers in excess of 4.5 pounds per gallon of VOCs.

B. Topcoats in excess of 3.5 pounds per gallon of VOCs.

Applications exempt from the 200-gallon limitation are defined in R307-355-3.

[R307-355-3, R307-355-5, R307-355-9]

II.B.4.a.1 Records for materials that do not pass through the RTO shall be maintained in a log indicating
the volume and date of products used. [R307-355-6, R307-401-8]

II.B.4.a.2 Compliance shall be determined on a rolling 12-month total. Based on the last day of each
month, a new 12-month total shall be calculated using data from the previous 12 months.
Monthly product inventories shall be made no later than 20 days after the end of each calendar
month. [R307-401-8]

DAQE-AN157060004-24
Page 10

II.B.4.b The owner/operator shall ensure all applications of primer and topcoats are applied via a HVLP,
or Electrostatic Spray. Exceptions to this condition for hand applications are as follows: HVLP
or Electrostatic may be substituted with hand application in instances where a spray gun is
unable to properly reach limited access space; fillers within the coating adversely impacting the
HVLP or Electrostatic applicator; stenciling, lettering, or identification markers applied; a hand-
held spray applied; for touch-ups and repairs; or the application of specialty coatings.
[R307-355-6]

II.B.5 RTO Requirements
II.B.5.a The owner/operator shall ensure the RTO system operates at all times, when the Downdraft Paint
Bay and Crossdraft Paint Bays are in use for priming, top coat, and stripping applications, except
when the cumulative airflow is below 25,000 CFM. [R307-401-8]

II.B.5.b The owner/operator shall operate the RTO for no less than three (3) hours during curing
applications. These hours shall begin at the start of the curing operation. [R307-401-8]

II.B.5.c The owner/operator shall operate the RTO at a temperature above 1,350 degrees Fahrenheit
while the concentrator wheels are in operation. [R307-401-8]

II.B.5.c.1 The owner/operator shall maintain a log of RTO inspections indicating, at minimum, the date
and temperature of the RTO during operations. [R307-401-8]

II.B.5.c.2 The owner/operator shall maintain records of the RTO operating parameters, verified by the
manufacturer, indicating the following programmed operations:

A. Curing application times: The RTO shall be programmed to run for no less than
three (3) hours for curing applications.

B. Bypass temperature: The bypass shall only open when temperature reaches 1600
degrees Fahrenheit or higher.

[R307-401-8]

II.B.5.d The owner/operator shall verify the capture and control efficiency of the RTO using methods of
verification compliant with R307-355-9 within no less than 3 months from the issuance of this
AO. [R307-355-9]

II.B.5.e The owner/operator shall maintain and operate the RTO according to manufacturer's
specifications for the life of the RTO. Records of inspection schedules, monitoring,
recordkeeping, and key parameters, as identified by the manufacturer, shall be kept for a
minimum of two (2) years. [R307-355-9]

II.B.5.f The owner/operator shall not allow visible emissions from the RTO to exceed 10% opacity.
[R307-401-8]

II.B.6 Spray Gun Requirements
II.B.6.a The owner/operator shall ensure all operators of spray guns are certified for the proper spray
application of surface coatings and the proper setup and maintenance of spray equipment.
[40 CFR 63, Subpart HHHHHH, R307-401-8]

II.B.6.b The owner/operator shall ensure spray gun cleaning is done in a manner that prevents atomized
mists or spraying of cleaning solvents beyond the cleaning solvent container. [40 CFR 63,
Subpart HHHHHH, R307-401-8]

DAQE-AN157060004-24
Page 11

PERMIT HISTORY

This Approval Order shall supersede (if a modification) or will be based on the following documents:

Supersedes AO DAQE-AN157060003-20 dated November 12, 2020

DAQE-AN157060004-24
Page 12

ACRONYMS

The following lists commonly used acronyms and associated translations as they apply to this document:

40 CFR Title 40 of the Code of Federal Regulations
AO Approval Order
BACT Best Available Control Technology
CAA Clean Air Act
CAAA Clean Air Act Amendments
CDS Classification Data System (used by Environmental Protection Agency to classify
sources by size/type)
CEM Continuous emissions monitor
CEMS Continuous emissions monitoring system
CFR Code of Federal Regulations
CMS Continuous monitoring system
CO Carbon monoxide
CO2 Carbon Dioxide
CO2e Carbon Dioxide Equivalent - Title 40 of the Code of Federal Regulations Part 98,
Subpart A, Table A-1
COM Continuous opacity monitor
DAQ/UDAQ Division of Air Quality
DAQE This is a document tracking code for internal Division of Air Quality use
EPA Environmental Protection Agency
FDCP Fugitive dust control plan
GHG Greenhouse Gas(es) - Title 40 of the Code of Federal Regulations 52.21 (b)(49)(i)
GWP Global Warming Potential - Title 40 of the Code of Federal Regulations Part 86.1818-
12(a)
HAP or HAPs Hazardous air pollutant(s)
ITA Intent to Approve
LB/YR Pounds per year
MACT Maximum Achievable Control Technology
MMBTU Million British Thermal Units
NAA Nonattainment Area
NAAQS National Ambient Air Quality Standards
NESHAP National Emission Standards for Hazardous Air Pollutants
NOI Notice of Intent
NOx Oxides of nitrogen
NSPS New Source Performance Standard
NSR New Source Review
PM10 Particulate matter less than 10 microns in size
PM2.5 Particulate matter less than 2.5 microns in size
PSD Prevention of Significant Deterioration
PTE Potential to Emit
R307 Rules Series 307
R307-401 Rules Series 307 - Section 401
SO2 Sulfur dioxide
Title IV Title IV of the Clean Air Act
Title V Title V of the Clean Air Act
TPY Tons per year
UAC Utah Administrative Code
VOC Volatile organic compounds

DAQE-

RN157060004
May 13, 2024

Cobi Lane
Duncan Aviation, Inc.
262 South 3800 West
Provo, UT 84601
[e-mail]

Dear Cobi Lane,

Re: Engineer Review - 10-Year Review and Permit Updates:
Administrative Amendment to Approval Order DAQE-AN157060003-20 to Correct Order of
Conditions
Project Number: N157060004

The DAQ requests a company representative review and sign the attached Engineer Review (ER). This
ER identifies all applicable elements of the New Source Review (NSR) permitting program. Duncan
Aviation, Inc. should complete this review within 10 business days of receipt.

Duncan Aviation, Inc. should contact Christine Bodell at [phone] if there are questions or
concerns with the review of the draft permit conditions. Upon resolution of your concerns, please email
Christine Bodell at [e-mail] the signed cover letter. Upon receipt of the signed cover letter,
the DAQ will prepare an Approval Order (AO) for signature by the DAQ Director.

If Duncan Aviation, Inc. does not respond to this letter within 10 business days, the project will move
forward without source concurrence. If Duncan Aviation, Inc. has concerns that cannot be resolved and
the project becomes stagnant, the DAQ Director may issue an Order prohibiting construction.

Approval Signature _____________________________________________________________
(Signature & Date)

195 North 1950 West • Salt Lake City, UT
Mailing Address: P.O. Box 144820 • Salt Lake City, UT 84114-4820
Telephone [phone] • Fax [phone] • T.D.D. [phone]
www.deq.utah.gov
Printed on 100% recycled paper
Department of
Environmental Quality

Kimberly D. Shelley Executive Director

DIVISION OF AIR QUALITY
Bryce C. Bird Director

State of Utah

SPENCER J. COX
Governor

DEIDRE HENDERSON
Lieutenant Governor

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 1
UTAH DIVISION OF AIR QUALITY
ENGINEER REVIEW

SOURCE INFORMATION

Project Number N157060004
Owner Name Duncan Aviation, Inc.
Mailing Address 262 South 3800 West
Provo, UT, 84601

Source Name Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and
Overhaul (MRO) Complex
Source Location 262 South 3800 West
Provo, UT 84601

UTM Projection 438,136 m Easting, 4,453,558 m Northing
UTM Datum NAD83
UTM Zone UTM Zone 12
SIC Code 4581 (Airports, Flying Fields, & Airport Terminal Services)

Source Contact Cobi Lane
Phone Number [phone]
Email [e-mail]

Billing Contact Cobi Lane
Phone Number [phone]
Email [e-mail]

Project Engineer Christine Bodell, Engineer
Phone Number [phone]
Email [e-mail]

Notice of Intent (NOI) Submitted April 22, 2024
Date of Accepted Application April 22, 2024

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 2
SOURCE DESCRIPTION

General Description
Duncan Aviation is an aircraft maintenance, repair, and overhaul site. The site operations include
airframe maintenance, aircraft on ground (AOG) emergency, avionics installation, interior and
paint refurbishment, and other engineering services. Emissions on site are generated through
stripping, sanding, painting, and detail work on the interior and exterior of aircraft. The on-site
fuel storage tanks will also contribute to source emissions.

Eleven small booths, in a separate building, are used for painting, finishes, cabinetry, upholstery,
completions, and structural processes. Filters, air re-circulation, and High-Volume, Low-Pressure
(HVLP) spray guns control emissions in the booths. Duncan Aviation, Inc. operates two paint
hangar bays and sixteen small operation booths consisting of painting, sanding, and gluing.
Aircraft will be parked in the hangar, where a stripping solution depaints the aircraft. Once the
aircraft is depainted, it is primed, painted, and allowed to air-dry in the hangar. The hangars are
controlled via a crossdraft and downdraft system.

NSR Classification:
10 Year Review

Source Classification
Located in Southern Wasatch Front O3 NAA, Provo UT PM2.5 NAA
Utah County
Airs Source Size: B

Applicable Federal Standards
MACT (Part 63), A: General Provisions
MACT (Part 63), CCCCCC: National Emission Standards for Hazardous Air Pollutants for
Source Category: Gasoline Dispensing Facilities
MACT (Part 63), HHHHHH: National Emission Standards for Hazardous Air Pollutants: Paint
Stripping and Miscellaneous Surface Coating Operations at Area Sources

Project Proposal
Administrative Amendment to Approval Order DAQE-AN157060003-20 to Correct Order of
Conditions

Project Description
This administrative amendment is to Approval Order DAQE-AN157060003-20, dated November
12, 2020. In Section II.B (Requirements and Limitations) of the AO, the conditions are listed out
of order. A new Approval Order will be issued to correct the minor administrative error and
incorporate updated language and formatting. No changes to equipment or emissions are being
made.

EMISSION IMPACT ANALYSIS
This is an administrative amendment to correct the order of conditions in the current AO. No changes to
equipment or emissions are being made at this time. Therefore, modeling is not required. [Last updated April
22, 2024]

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 3
SUMMARY OF EMISSIONS

The emissions listed below are an estimate of the total potential emissions from the source. Some
rounding of emissions is possible.

Criteria Pollutant Change (TPY) Total (TPY)
CO2 Equivalent 0 7126.90
Carbon Monoxide 0 4.73
Nitrogen Oxides 0 4.38
Particulate Matter - PM10 0 0.66
Particulate Matter - PM2.5 0 0.66
Sulfur Dioxide 0 0.09
Volatile Organic Compounds 0 32.02

Hazardous Air Pollutant Change (lbs/yr) Total (lbs/yr)
Ethyl Benzene (CAS #100414) 0 520
Ethylene Glycol (CAS #107211) 0 900
Generic HAPs (CAS #GHAPS) 0 480
Glycol Ethers (CAS #EDF109) 0 1040
Hexane (CAS #110543) 0 1660
Methyl Isobutyl Ketone (Hexone) (CAS #108101) 0 1400
Toluene (CAS #108883) 0 2740
Xylenes (Isomers And Mixture) (CAS #1330207) 0 2520
Change (TPY) Total (TPY)
Total HAPs 0 5.63

Note: Change in emissions indicates the difference between previous AO and proposed modification.

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 4
Review of BACT for New/Modified Emission Units

1. BACT review regarding Administrative Amendment
This is an administrative amendment to correct the order of conditions in the current AO. No
changes to equipment or emissions are being made at this time. Therefore, a BACT analysis is not
required. [Last updated April 22, 2024]

SECTION I: GENERAL PROVISIONS

The intent is to issue an air quality AO authorizing the project with the following recommended
conditions and that failure to comply with any of the conditions may constitute a violation of the
AO. (New or Modified conditions are indicated as “New” in the Outline Label):

I.1 All definitions, terms, abbreviations, and references used in this AO conform to those used in
the UAC R307 and 40 CFR. Unless noted otherwise, references cited in these AO conditions
refer to those rules. [R307-101]

I.2 The limits set forth in this AO shall not be exceeded without prior approval. [R307-401]

I.3 Modifications to the equipment or processes approved by this AO that could affect the
emissions covered by this AO must be reviewed and approved. [R307-401-1]

I.4 All records referenced in this AO or in other applicable rules, which are required to be kept by
the owner/operator, shall be made available to the Director or Director's representative upon
request, and the records shall include the two-year period prior to the date of the request.
Unless otherwise specified in this AO or in other applicable state and federal rules, records
shall be kept for a minimum of two (2) years. [R307-401-8]

I.5 At all times, including periods of startup, shutdown, and malfunction, owners and operators
shall, to the extent practicable, maintain and operate any equipment approved under this AO,
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.
All maintenance performed on equipment authorized by this AO shall be recorded. [R307-
401-4]

I.6 The owner/operator shall comply with UAC R307-107. General Requirements: Breakdowns.
[R307-107]

I.7 The owner/operator shall comply with UAC R307-150 Series. Emission Inventories. [R307-
150]

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 5
SECTION II: PERMITTED EQUIPMENT
The intent is to issue an air quality AO authorizing the project with the following recommended
conditions and that failure to comply with any of the conditions may constitute a violation of the
AO. (New or Modified conditions are indicated as “New” in the Outline Label):

II.A THE APPROVED EQUIPMENT

II.A.1 Duncan Aviation
Aircraft Maintenance, Repair, and Overhaul Complex

II.A.2 Two (2) Paint Bays
Downdraft Paint Bay: PPH1
Control: RTO, 3-stage particulate filters, downdraft ventilation
Total Volume: 250,000 CFM

Crossdraft Paint Bays: PPH2
Control: RTO, 3-stage filters, crossdraft ventilation
Total Volume: 150,000 CFM

MACT Applicability: Subpart HHHHHH

II.A.3 Small Booths: Six (6) Paint Booths
Booths:
(1) PPTPB1
(2) PACPB1
(3) PFNPB1
(4) PUPPB1
(5) PITPB1
(6) PVSPB1

Controls:
3- stage particulate filters (control efficiency: 99%)
Full roof and 4 walls or within an enclosed room
HVLP or electrostatic spray gun paint application

MACT Applicability: Subpart HHHHHH

II.A.4 Small Booths: Two (2) Paint Booths
(1) PFNPB3
(2) PFNPB2

Controls:
Single stage particulate filters (control efficiency: 99%)
Full roof and 4 walls or within an enclosed room
HVLP or electrostatic spray gun paint application

MACT Applicability: None

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 6
II.A.5 Sanding Operations
Tables (All tables and controls vent internally):
(1) Finish Shop
(2) Structures Shop
(3) Interior Completions
(4) Building 2
(5) Upholstery

Additional controls:
Downdraft table with filters and dust collectors
MACT Applicability: Subpart HHHHHH

II.A.6 Small Booths: Three (3) Glue Booths
Booths:
(1) PCBGB1
(2) PUPGB1
(3) PITGB1

Controls:
Negative pressure air system
Two stage particulate filter

MACT Applicability: Subpart HHHHHH

II.A.7 Concentrator Regenerative Thermal Oxidizer (RTO)
Fuel: Natural Gas
Includes: Emergency Bypass
Maximum Rating: 10.5 MMBtu/hr

II.A.8 Spray Guns
Style: HVLP or electrostatic

II.A.9 Three (3) Storage Tanks
Fuel: Jet Fuel
Maximum Capacity: 30,000 gallons each
MACT and NSPS Applicability: None

II.A.10 Storage Tanks
Fuel: Diesel and Unleaded Gas
Maximum Capacity: Equal to or less than 600 gallons each
MACT Applicability: Subpart CCCCCC

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 7
II.A.11 Miscellaneous Equipment
Four (4) Boilers
Fuel: Natural Gas
Maximum Rating: < 5 MMBtu/hr, each
MACT and NSPS Applicability: None

One (1) Wastewater Evaporator
Fuel: Natural Gas
Maximum Rating: < 5 MMBtu/hr
MACT and NSPS Applicability: None

SECTION II: SPECIAL PROVISIONS
The intent is to issue an air quality AO authorizing the project with the following recommended
conditions and that failure to comply with any of the conditions may constitute a violation of the
AO. (New or Modified conditions are indicated as “New” in the Outline Label):

II.B REQUIREMENTS AND LIMITATIONS

II.B.1 Site wide Limits and Requirements
II.B.1.a
NEW
Unless otherwise specified in this AO, the owner/operator shall not allow visible emissions to
exceed 20% opacity. [R307-401-8]

II.B.1.a.1
NEW
Opacity observations of emissions from stationary sources shall be conducted in accordance
with 40 CFR 60, Appendix A, Method 9. [R307-401-8]

II.B.1.b
NEW
The owner/operator shall not allow plant wide emissions of VOCs and HAPs from the paint
hangers and painting, sanding, finishing, and glue booths to exceed the following values:

A. 32.02 tons per rolling 12-month period for VOCs

B. 0.83 tons per rolling 12-month period for Hexane

C. 1.37 tons per rolling 12-month period for Toluene

D. 1.26 tons per rolling 12-month period for Xylene

E. 0.70 tons per rolling 12-month period for Methyl Isobutyl Ketone

F. 0.52 tons per rolling 12-month period for Glycol Ether

G. 0.09 tons per rolling 12-month period for Chromium

H. 1720 pounds (0.86 tons) per rolling 12-month period for all other cumulative HAPs

[R307-401-8]

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 8
II.B.1.b.1
NEW
The owner/operator shall calculate a new 12-month total by the 20th day of each month using
data from the previous 12 months. The owner/operator shall use a mass-balance method to
calculate emissions from evaporative sources. The owner/operator may use the following
equations with applicable units to comply with the mass-balance method:

VOC = (% VOC by Weight)/100 x [Density (lb/gal)] x Gal Consumed x 1 ton/2000 lb x EF*

HAP = (% HAP by Weight)/100 x [Density (lb/gal)] x Gal Consumed x 1 ton/2000 lb x EF*

* EF is the applicable emission factor provided on the manufacture SDS sheet.

When the RTO is used for emission reductions, the owner/operator may use the following
equations to determine emission totals after control.

VOCs = [VOCs determined by mass-balance method] x [1 - 85%]

HAPs = [HAPs determined by mass-balance method] x [1 - 85%]

[R307-401-8]

II.B.1.b.2
NEW
The owner/operator shall use a mass-balance method to quantify any amount of VOCs and
HAP(s) reclaimed. The owner/operator shall subtract the amount of VOCs and HAP(s)
reclaimed from the quantities calculated above to provide the monthly total emissions of
VOCs and HAPs. [R307-401-8]

II.B.1.b.3
NEW
The owner/operator shall keep records of each month of the following, for each material used:

A. Name of the VOC and HAPs emitting material, such as: paint, adhesive, solvent,
thinner, reducers, chemical compounds, toxics, isocyanates, etc.

B. Density of each material used (pounds per gallon)

C. Percent by weight of all VOC and HAP in each material used

D. Gallons of each VOC and HAP emitting material used

E. The applicable EF provided on the manufacture SDS sheet of each material
used

F. The amount of VOC and HAP emitted by each material used

G. The amount of VOC and HAP reclaimed from each material used

H. The total amount of VOCs and/or HAP emitted monthly from all materials used.

[R307-401-8]

II.B.1.c Except when in use, the owner/operator shall store VOC/HAPs-containing materials and
VOC/HAPs-laden rags in covered containers. [R307-355-7, R307-401-8]

II.B.2 Small Booths Requirements

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 9
II.B.2.a The owner/operator shall ensure each small booth is equipped with a set of paint arrestor
particulate filters, or equivalent, to control particulate emissions. All air exiting small booths
shall pass through this control system before being vented to the atmosphere (outside
building/operation). [R307-401-8]

II.B.2.b The owner/operator shall not allow visible emissions from small booth operations to exceed
10% opacity. [R307-401-8]

II.B.3 Tank Requirements
II.B.3.a The owner/operator shall operate and maintain all tanks in accordance with the manufacturer's
instructions. [R307-401-8]

II.B.4 Paint Requirements
II.B.4.a
NEW
The owner/operator shall route all primers and topcoats, defined below, through the RTO once
use meets or exceeds 200 gallons per rolling 12-month period:

A. Primers in excess of 4.5 pounds per gallon of VOCs

B. Topcoats in excess of 3.5 pounds per gallon of VOCs

Applications exempt from the 200-gallon limitation are defined in R307-355-3.

[R307-355-3, R307-355-5, R307-355-9]

II.B.4.a.1 Records for materials that do not pass through the RTO shall be maintained in a log indicating
the volume and date of products used. [R307-355-6, R307-401-8]

II.B.4.a.2 Compliance shall be determined on a rolling 12-month total. Based on the last day of each
month, a new 12-month total shall be calculated using data from the previous 12 months.
Monthly product inventories shall be made no later than 20 days after the end of each calendar
month. [R307-401-8]

II.B.4.b The owner/operator shall ensure all applications of primer and topcoats are applied via a
HVLP or Electrostatic Spray. Exceptions to this condition for hand applications are as
follows: HVLP or Electrostatic may be substituted with hand application in instances where a
spray gun is unable to properly reach limited access space; fillers within the coating adversely
impacting the HVLP or Electrostatic applicator; stenciling, lettering, or identification markers
applied; a hand-held spray applied; for touch-ups and repairs; or the application of specialty
coatings. [R307-355-6]

II.B.5 RTO Requirements
II.B.5.a The owner/operator shall ensure the RTO system operates at all times, when the Downdraft
Paint Bay and Crossdraft Paint Bays are in use for priming, top coat, and stripping
applications except when the cumulative airflow is below 25,000 CFM. [R307-401-8]

II.B.5.b The owner/operator shall operate the RTO for no less than three hours during curing
applications. These hours shall begin at the start of the curing operation. [R307-401-8]

II.B.5.c The owner/operator shall operate the RTO at a temperature above 1,350 degrees Fahrenheit
while the concentrator wheels are in operation. [R307-401-8]

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 10
II.B.5.c.1 The owner/operator shall maintain a log of RTO inspections indicating, at minimum, the date
and temperature of the RTO during operations. [R307-401-8]

II.B.5.c.2
NEW
The owner/operator shall maintain records of the RTO operating parameters, verified by the
manufacturer, indicating the following programed operations:

A. Curing application times: The RTO shall be programmed to run for no less than three
hours for curing applications.

B. Bypass temperature: The bypass shall only open when temperature reaches 1600
degrees Fahrenheit or higher.

[R307-401-8]

II.B.5.d The owner/operator shall verify the capture and control efficiency of the RTO using methods
of verification compliant with R307-355-9 within no less than 3 months from the issuance of
this AO. [R307-355-9]

II.B.5.e The owner/operator shall maintain and operate the RTO according to manufacturer's
specifications for the life of the RTO. Records of inspection schedules, monitoring,
recordkeeping, and key parameters, as identified by the manufacturer, shall be kept for a
minimum of two years. [R307-355-9]

II.B.5.f The owner/operator shall not allow visible emissions from the RTO to exceed 10% opacity.
[R307-401-8]

II.B.6 Spray Gun Requirements
II.B.6.a The owner/operator shall ensure all operators of spray guns are certified for the proper spray
application of surface coatings and the proper setup and maintenance of spray equipment. [40
CFR 63 Subpart HHHHHH, R307-401-8]

II.B.6.b The owner/operator shall ensure spray gun cleaning is done in a manner that prevents
atomized mists or spraying of cleaning solvents beyond the cleaning solvent container. [40
CFR 63 Subpart HHHHHH, R307-401-8]

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 11
PERMIT HISTORY

When issued, the approval order shall supersede (if a modification) or will be based on the
following documents:

Supersedes AO DAQE-AN157060003-20 dated October 12, 2020

REVIEWER COMMENTS

1. Comment regarding Federal Subpart Applicability:
40 CFR 60 Subpart Kb for Volatile Organic Liquid (VOL) Storage Vessels (including Petroleum
Liquids Storage Vessels)
This Subpart applies to storage tanks with a design capacity greater than or equal to 75 m3 (19,812.9
gallons) but less than 151 m3 containing a VOL that, as stored, has a maximum true vapor pressure
equal to or greater than 27.6 kPa but less than 76.6 kPa. Duncan Aviation stores jet fuel on site in a
30,000-gallon tank; jet fuel has a vapor pressure of 0.199 kPa less than 27.6 kPa. Therefore, NSPS
Subpart Kb does not apply to this source.

40 CFR 63 Subpart CCCCCC for Hazardous Air Pollutants for Source Category: Gasoline
Dispensing Facilities
This Subpart applies to gasoline dispensing facilities (GDF) which dispense gasoline into fuel tanks
of motor vehicles. MACT Subpart CCCCCC applies to this facility. A GDF with a monthly
throughput of less than 10,000 gallons of gasoline must meet recordkeeping and best practices as
outlined in section 63.11116. No other requirements are necessary under this subpart.

40 CFR 63 Subpart HHHHHH- National Emission Standards for Hazardous Air Pollutants: Paint
Stripping and Miscellaneous Surface Coating Operations at Area Sources
This Subpart applies to new or reconstructed sources, constructed on or after January 9, 2008, that
perform applications of coatings to mobile equipment including mobile repair and refinishing
operations. Subject coatings are defined as a material spray-applied to a substrate for functional
purposes. Spray applications are defined as coatings applied using a hand-held device that creates an
atomized mist of a coating and is deposited on a substrate. Duncan Aviation uses high-volume low-
pressure (HVLP) spray equipment to paint aircrafts on site. Therefore, MACT Subpart HHHHHH
applies to this facility. [Last updated April 22, 2024]

2. Comment regarding Title V Applicability:
Title V of the 1990 Clean Air Act (Title V) applies to the following:

1. Any major source
2. Any source subject to a standard, limitation, or other requirement under Section 111 of the Act,
Standards of Performance for New Stationary Sources;
3. Any source subject to a standard or other requirement under Section 112 of the Act, Hazardous
Air Pollutants.
4. Any Title IV affected source.

This facility is not a major source and is not a Title IV source. The facility is not subject to 40 CFR
60 (NSPS) and/or 40 CFR 61 (NESHAP) regulations. The facility is subject to 40 CFR 63 (MACT)
Subparts A, HHHHHH, and CCCCCC. However, MACT Subpart HHHHHH and Subpart CCCCCC
each specifically exempt sources from the obligation to obtain a Title V permit, if the sources are not
otherwise required for a Title V permit. No such reasons exist. Therefore, this facility is not a Title V

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 12
source. [Last updated April 22, 2024]

Engineer Review N157060004: Duncan Aviation, Inc.- Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
May 13, 2024
Page 13
ACRONYMS
The following lists commonly used acronyms and associated translations as they apply to this
document:
40 CFR Title 40 of the Code of Federal Regulations
AO Approval Order
BACT Best Available Control Technology
CAA Clean Air Act
CAAA Clean Air Act Amendments
CDS Classification Data System (used by EPA to classify sources by size/type)
CEM Continuous emissions monitor
CEMS Continuous emissions monitoring system
CFR Code of Federal Regulations
CMS Continuous monitoring system
CO Carbon monoxide
CO2 Carbon Dioxide
CO2e Carbon Dioxide Equivalent - 40 CFR Part 98, Subpart A, Table A-1
COM Continuous opacity monitor
DAQ/UDAQ Division of Air Quality
DAQE This is a document tracking code for internal UDAQ use
EPA Environmental Protection Agency
FDCP Fugitive dust control plan
GHG Greenhouse Gas(es) - 40 CFR 52.21 (b)(49)(i)
GWP Global Warming Potential - 40 CFR Part 86.1818-12(a)
HAP or HAPs Hazardous air pollutant(s)
ITA Intent to Approve
LB/HR Pounds per hour
LB/YR Pounds per year
MACT Maximum Achievable Control Technology
MMBTU Million British Thermal Units
NAA Nonattainment Area
NAAQS National Ambient Air Quality Standards
NESHAP National Emission Standards for Hazardous Air Pollutants
NOI Notice of Intent
NOx Oxides of nitrogen
NSPS New Source Performance Standard
NSR New Source Review
PM10 Particulate matter less than 10 microns in size
PM2.5 Particulate matter less than 2.5 microns in size
PSD Prevention of Significant Deterioration
PTE Potential to Emit
R307 Rules Series 307
R307-401 Rules Series 307 - Section 401
SO2 Sulfur dioxide
Title IV Title IV of the Clean Air Act
Title V Title V of the Clean Air Act
TPY Tons per year
UAC Utah Administrative Code
VOC Volatile organic compounds

Christine Bodell <[e-mail]>
Duncan Aviation, Inc. - Aircraft Maintenance, Repair, and Overhaul (MRO) Complex
6 messages
Christine Bodell <[e-mail]>Wed, Apr 17, 2024 at 12:32 PM
To: [e-mail]
Cc: Chad Gilgen <[e-mail]>
Good Morning Mr. Walker,
I have come across Approval Order (AO) DAQE-AN157060003-20, dated November 12, 2020 (see attached), for Duncan Aviation, Inc.'s
Aircraft Maintenance, Repair, and Overhaul (MRO) Complex in Provo.The most recent compliance inspection has you listed as a contact.
I noticed that the conditions in Section II.B are out of order. I will be re-issuing the Approval Order to correct this, at no cost to Duncan
Aviation. Before I move forward with this, can you please advise if everything else on the Approval Order is still accurate?
Thank you,
Christine
--
Christine Bodell
Environmental Engineer
Email | [e-mail]
Phone| [phone]
Emails to and from this email address may be considered public records and
thus subject to Utah GRAMA requirements
DAQE-AN157060003-20.pdf
541K
Chad Gilgen <[e-mail]>Wed, Apr 17, 2024 at 3:13 PM
To: Bruce Jensen <[e-mail]>
Cc: Christine Bodell <[e-mail]>, Todd Walker <[e-mail]>
Hello Bruce,
Please see the following email from Christine Bodell with our permitting group. I wanted to forward this to your attention since my most
recent correspondence has been with you rather than Todd to make sure Christine's inquiry is getting to the right point of contact.
Thanks,
Chad
Chad Gilgen | Manager | Minor Source Compliance
385-306-6500 (cell)
Emails to and from this email address may be considered public records and thus subject to Utah GRAMA requirements.
[Quoted text hidden]
DAQE-AN157060003-20.pdf
541K
Todd Walker <[e-mail]>Thu, Apr 18, 2024 at 8:14 PM
To: Chad Gilgen <[e-mail]>, Bruce Jensen <[e-mail]>
Cc: Christine Bodell <[e-mail]>
Thanks Chad
Sent via the Samsung Galaxy S22 5G, an AT&T 5G smartphone
Get Outlook for Android
From: Chad Gilgen <[e-mail]>
Sent: Wednesday, April 17, 2024 3:13:51 PM
To: Bruce Jensen <[e-mail]>
Cc: Chrisne Bodell <[e-mail]>; Todd Walker <[e-mail]>
Subject: Fwd: Duncan Aviaon, Inc. - Aircra Maintenance, Repair, and Overhaul (MRO) Complex

[Quoted text hidden]
Bruce Jensen <[e-mail]>Fri, Apr 19, 2024 at 8:06 AM
To: Chad Gilgen <[e-mail]>
Cc: Christine Bodell <[e-mail]>, Todd Walker <[e-mail]>
Hi Chad,
Thank you for forwarding that to me Chad. There is a change to this that I wanted to let you know about. Our source
contact for this facility has changed. Previously it was...
Chad Doehring
[phone]
[e-mail]
Our new Source Contact for our Provo facility is
Cobi Lane
[phone]
[e-mail]
That looks like the only change to this. Please connue to send emails to me for the Provo facility.
Have a great weekend.
Thank you,
Bruce

Bruce Jensen 
Environmental Supervisor
DIRECT: [phone] | CELL: [phone]
www.DuncanAviation.aero
From: Chad Gilgen <[e-mail]>
Sent: Wednesday, April 17, 2024 3:13 PM
To: Bruce Jensen <[e-mail]>
Cc: Chrisne Bodell <[e-mail]>; Todd Walker <[e-mail]>
Subject: Fwd: Duncan Aviaon, Inc. - Aircra Maintenance, Repair, and Overhaul (MRO) Complex

[Quoted text hidden]
Christine Bodell <[e-mail]>Mon, Apr 22, 2024 at 8:29 AM
To: Bruce Jensen <[e-mail]>
Cc: Chad Gilgen <[e-mail]>, Todd Walker <[e-mail]>
Good Morning Bruce,
Thank you for the information. So just to confirm - everything else on the current Approval, including the equipment, is still accurate?
If so, I will proceed with add the new contact and reissue the Approval Order with updated language and formatting.
Thank you,
Christine
[Quoted text hidden]
Bruce Jensen <[e-mail]>Mon, Apr 22, 2024 at 9:11 AM
To: Christine Bodell <[e-mail]>
Cc: Chad Gilgen <[e-mail]>, Todd Walker <[e-mail]>, Nate Hansen
<[e-mail]>
There is one more thing to change in this Approval Order regarding the equipment that was overlooked earlier.
ILA.4 Small Booths: Two (2) Paint Booths
 PFNPB3 is small paint booth that doesn't exist yet. It is a downdra paint booth that we plan to build in the future in our
Cabinet/Finish Shop as we get busier. The floor was built so that we can add it later, but there's nothing there now.
That should be it.
Thank you and have a great day.
Bruce

Bruce Jensen 
Environmental Supervisor
DIRECT: [phone] | CELL: [phone]
www.DuncanAviation.aero
From: Chrisne Bodell <[e-mail]>
Sent: Monday, April 22, 2024 8:29 AM
To: Bruce Jensen <[e-mail]>
Cc: Chad Gilgen <[e-mail]>; Todd Walker <[e-mail]>
Subject: Re: Duncan Aviaon, Inc. - Aircra Maintenance, Repair, and Overhaul (MRO) Complex

[Quoted text hidden]