DAQ-2024-011117

DAQE-AN103670031-24

{{$d1 }}

Stewart Hogan
Asahi Refining USA, Inc.
4601 West 2100 South
West Valley City, UT 84120
[e-mail]

Dear Mr. Hogan:

Re: Approval Order: Modification to Approval Order DAQE-AN103670030-24 to Add One (1)
Emergency Engine and One (1) Electric Furnace
Project Number: N103670031

The attached Approval Order (AO) is issued pursuant to the Notice of Intent (NOI) received on July 26,
2024. Asahi Refining USA, Inc. 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: Salt Lake 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

October 7, 2024

STATE OF UTAH
Department of Environmental Quality
Division of Air Quality

{{#s=Sig_es_:signer1:signature}}
{{#d1=date1_es_:signer1:date:format(date, "mmmm d, yyyy")}}
{{#d2=date1_es_:signer1:date:format(date, "mmmm d, yyyy"):align(center)}}

APPROVAL ORDER
DAQE-AN103670031-24
Modification to Approval Order DAQE-AN103670030-24 to Add
One (1) Emergency Engine and One (1) Electric Furnace

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

Issued to
Asahi Refining USA, Inc. - Precious Metals Refinery

Issued On
{{$d2 }}

Issued By

{{$s }}

Bryce C. Bird
Director
Division of Air Quality

October 7, 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 ................................................................................................. 3
Project Description.................................................................................................................. 4
SUMMARY OF EMISSIONS .................................................................................................... 4
SECTION I: GENERAL PROVISIONS .................................................................................... 5
SECTION II: PERMITTED EQUIPMENT .............................................................................. 5
SECTION II: SPECIAL PROVISIONS ..................................................................................... 8
PERMIT HISTORY ................................................................................................................... 11
ACRONYMS ............................................................................................................................... 12

DAQE-AN103670031-24
Page 3

GENERAL INFORMATION

CONTACT/LOCATION INFORMATION

Owner Name Source Name
Asahi Refining USA, Inc. Asahi Refining USA, Inc. - Precious Metals Refinery

Mailing Address Physical Address
4601 West 2100 South 4601 West 2100 South
West Valley City, UT 84120 West Valley City, UT 84120

Source Contact UTM Coordinates
Name: Stewart Hogan 415,495 m Easting
Phone: [phone],508,700 m Northing
Email: [e-mail] Datum NAD83
UTM Zone 12
SIC code 3339 (Primary Smelting & Refining of Nonferrous Metals, Except Copper & Aluminum)

SOURCE INFORMATION
General Description
Asahi Refining USA, Inc. (Asahi) currently operates a precious metals refinery in West Valley City, Salt
Lake County. Mined doré and scrap are melted and tested for purity using small electric induction
furnaces and then separated depending on gold and silver content. Separation is achieved by using various
inorganic chemicals and electrolytic methods. Silver is poured into anode molds and then placed into the
electrolytic cells. The cells contain silver nitrate solution, and the low voltage current causes silver crystal
to form onto a cathode plate. The silver crystal is scraped off and collected.

NSR Classification
Minor Modification at Minor Source
Source Classification
Located in Northern Wasatch Front O3 NAA, Salt Lake City UT PM2.5 NAA, Salt Lake County SO2
NAA
Salt Lake County
Airs Source Size: B
Applicable Federal Standards
NSPS (Part 60), A: General Provisions
NSPS (Part 60), JJJJ: Standards of Performance for Stationary Spark Ignition Internal
Combustion Engines
MACT (Part 63), A: General Provisions
MACT (Part 63), ZZZZ: National Emissions Standards for Hazardous Air Pollutants for
Stationary Reciprocating Internal Combustion Engines
DAQE-AN103670031-24
Page 4

Project Description
Asahi has requested to add one (1) new electric tilt furnace. The new electric tilt furnaces will have the
same control technologies as the existing electric tilt furnaces: a nanofilter baghouse made by UAS or the
combination of the venturi scrubber, WESP II, and scrubber #359. Asahi is not requesting to increase any
production and/or operational limits. No emissions are increasing as a result of the new electric furnace.
Equipment ID # II.A.15 has been updated to reflect the additional electric tilt furnace.

Asahi is also requested to add one (1) EPA-certified, 850 horsepower (550 kW) natural gas-fired
emergency generator engine to provide power to the existing scrubbers and other critical equipment
during a loss of line power.

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)
Ammonia 0 0.06
CO2 Equivalent 0 994.70
Carbon Monoxide 0.07 0.80
Lead 0 0.01
Nitrogen Oxides 0.04 4.35
Particulate Matter - PM10 0 2.01
Particulate Matter - PM2.5 0 2.01
Sulfur Dioxide 0 6.11
Volatile Organic Compounds 0.07 0.16

Hazardous Air Pollutant Change (lbs/yr) Total (lbs/yr)
Chlorine (CAS #7782505) 0 800
Formaldehyde (CAS #50000) 31 31
Generic HAPs (CAS #GHAPS) 10 10
Hexane (CAS #110543) 0 20
Hydrochloric Acid (Hydrogen Chloride) (CAS #7647010) 0 1600
Lead (CAS #7439921) 0 20
Selenium & Compounds (CAS #253) 0 60
Change (TPY) Total (TPY)
Total HAPs 0.02 1.27

DAQE-AN103670031-24
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] I.8 The owner/operator shall submit documentation of the status of construction or modification to the Director within 18 months from the date of this AO. This AO may become invalid if construction is not commenced within 18 months from the date of this AO 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. [R307-401-18]

SECTION II: PERMITTED EQUIPMENT
II.A THE APPROVED EQUIPMENT
II.A.1 Metal Refinery
Precious Metals Refinery Plant.
II.A.2 Wastewater Treatment Wastewater effluent treatment. Process controlled by scrubber #760.
II.A.3 Electrolytic Cells
Silver electrolytic cell (refining of silver). Process controlled by scrubber #761.

DAQE-AN103670031-24
Page 6

II.A.4 Electrolytic Cells Gold electrolytic cell (refining of gold). Process controlled by scrubber #359. II.A.5 Wet Circuit Gold refinery wet circuits (part of the gold refining process). Process controlled by scrubber
#359.
II.A.6 Chlorination Gold chloride electrolytic production (refining of gold). Process controlled by scrubber #359. II.A.7 Slime Washing Silver anode slime washing process (recovery of gold). Process controlled by scrubber #248.

II.A.8 Wet Chlorides Treatment Hydrometallurgical process for silver chlorides sludge processing (recovery of gold). Controlled by scrubber #359. II.A.9 Fabric-Filter Baghouse
Four (4) fabric-filter baghouses
One baghouse controls emissions from the sweeps preparation process. Two baghouses control
emissions from the melt room furnaces, the electric tilt furnaces, and the electric push-out
furnaces. One baghouse controls the ashing furnace (Item II.A.25).
II.A.10 Boiler One (1) boiler, natural gas-fueled, rated less than 5 MMBtu/hr. II.A.11 Dust Collector
Dust collector for welding fume and grinding dust control in maintenance shop.

II.A.12 Electrostatic Precipitator One (1) wet-electrostatic precipitator (ID: WESP II).
II.A.13 Chlorination Furnaces Four (4) electric-induction chlorination furnaces. Process controlled by venturi scrubber, WESP
II, and scrubber #359.

II.A.14 Melt Furnaces Two (2) melt-room furnaces, natural gas-fueled, rated less than 5 MMBtu/hr each. Process controlled by a nanofilter baghouse made by UAS or the combination of the venturi scrubber, WESP II, and scrubber #359.
II.A.15 Tilt Furnaces (One (1) New)
Nine (9) electric-tilt furnaces. Process controlled by a nanofilter baghouse made by UAS or the combination of the venturi scrubber, WESP II, and scrubber #359.

II.A.16 Push-out Furnaces Four (4) electric push-out furnaces. Process controlled by baghouse or the combination of the venturi scrubber, WESP II, and scrubber #359.
II.A.17 Combustion Afterburner
One (1) incinerator, natural gas-fueled, rated less than 5 MMBtu/hr.

II.A.18 Nitrate Plant Silver nitrate plant (recovery of silver). Process controlled by scrubber #248.
DAQE-AN103670031-24
Page 7

II.A.19 Slime Plant Slime plant (recovery of gold). Process controlled by scrubber #248. II.A.20 Drying Cabinets Five (5) electric drying cabinets. Process controlled by the combination of the venturi scrubber,
WESP II, and scrubber #359.
II.A.21 Drying Cabinet One (1) drying cabinet, natural gas-fueled, rated less than 5 MMBtu/hr. II.A.22 Wet Scrubbers Four (4) packed bed wet scrubbers (ID: 760, 359, 248, 761).

II.A.23 Venturi Scrubber One (1) venturi scrubber attached to WESP II as a pre-scrubber.
II.A.24 Tank System Silver reduction tanks (recovery of silver). Process controlled by scrubber #248.

II.A.25 Ashing Furnace One (1) dental scrap ashing furnace. Process controlled by baghouse (Item II.A.9) and activated carbon adsorption system (Item II.A.26).
II.A.26 Activated Carbon Adsorption System One (1) activated carbon adsorption system controls the ashing furnace (Item II.A.25).

II.A.27 Emergency Generator Engine Rating: 60 kW Manufacture Year: Pre-2006 Fuel: Natural Gas NSPS Subpart Applicability: None MACT Subpart Applicability: Subpart ZZZZ II.A.28 Emergency Engine (New)
Rating: 850 hp (550 kW)
Manufacture Year: 2022 Fuel: Natural Gas

NSPS Subpart Applicability: Subpart JJJJ MACT Subpart Applicability: Subpart ZZZZ

DAQE-AN103670031-24
Page 8

SECTION II: SPECIAL PROVISIONS
II.B REQUIREMENTS AND LIMITATIONS

II.B.1 Site-Wide Requirements
II.B.1.a The owner/operator shall not allow visible emissions from the following emission points to
exceed the following values:

A. All fabric filter baghouse exhaust stacks - 10%.

B. All electrostatic precipitator exhaust stacks - 10%.

C. All scrubber exhaust stacks - 10%.

D. All incinerator exhaust stacks - 10%.

E. All boiler exhaust stacks - 10%.

F. All other points - 20%.

[R307-401-8]

II.B.1.a.1 Opacity observations of emissions from stationary sources shall be conducted according to 40 CFR 60, Appendix A, Method 9. [R307-401-8]
II.B.1.b The owner/operator shall not produce more than the following:

A. 12,000,000 troy ounces of gold per rolling 12-month period.

B. 60,000,000 troy ounces of silver per rolling 12-month period.

C. 400 tons of sweeps per rolling 12-month period.

[R307-401-8]

II.B.1.b.1 The owner/operator shall: A. Determine gold, silver, and sweeps production by company production records. B. Record gold and silver production on a daily basis and record sweeps production on a monthly basis. C. Use the gold and silver production data to calculate a new rolling 12-month total by the 20th day of each month using data from the previous 12 months. D. Use the sweeps production data to calculate a new rolling 12-month total by the 20th day of January, April, July, and October of each year using data from the previous 12 months. E. Keep the gold, silver, and sweeps production records for all periods the plant is in operation. [R307-401-8]

DAQE-AN103670031-24
Page 9

II.B.2 Baghouse Requirements II.B.2.a The owner/operator shall use baghouses to control particulate emissions from the sweeps
preparation process, melt room furnaces, electric tilt furnaces, electric push-out furnaces, and the ashing furnace. [R307-401-8]
II.B.2.b The owner/operator shall install a manometer or magnehelic pressure gauge to measure the static pressure differential across each baghouse. [R307-401-8] II.B.2.b.1 The pressure gauge shall be located such that an inspector/operator can safely read the indicator
at any time. [R307-401-8]
II.B.2.b.2 The pressure gauge shall measure the static pressure differential in 1-inch water column increments or less. [R307-401-8] II.B.2.c During operation of each baghouse, the owner/operator shall maintain the static pressure
differential within the range recommended by the manufacturer for normal operations.
[R307-401-8]
II.B.2.c.1 The owner/operator shall record the static pressure differential at least once per operating day while each baghouse is operating. [R307-401-8] II.B.2.c.2 The owner/operator shall maintain the following records of the static pressure differential:

A. Unit identification;
B. Manufacturer recommended static pressure differential range for the unit;
C. Daily static pressure differential readings;

D. Date of reading.
[R307-401-8]

II.B.2.d At least once every 12 months, the owner/operator shall calibrate each pressure gauge in accordance with the manufacturer's instructions or replace the pressure gauge. [R307-401-8]
II.B.2.d.1 The owner/operator shall maintain records of each pressure gauge calibrations and replacements. [R307-401-8]

DAQE-AN103670031-24
Page 10

II.B.3 Wet Scrubber Requirements II.B.3.a The owner/operator shall use the following scrubbers to control the following process streams.
Scrubber Process Stream Scrubber #248 silver anode slime washing process, silver nitrate plant, and slime
plant Scrubber #359 gold electrolytic cells, gold refinery wet circuits, gold chloride
electrolytic production, silver chlorides sludge processing, chlorination furnaces, melt furnaces, tilt furnaces, push-out furnaces, and drying cabinets
Scrubber #760 wastewater treatment tanks and laboratory
Scrubber #761 silver electrolytic cells
All exhaust air from the above-mentioned process streams shall be routed through the indicated
scrubber before being vented to the atmosphere.
[R307-401-8]

II.B.3.b During operation of each scrubber, the owner/operator shall maintain both the pressure drop and the liquid flow rate within the respective range recommended by the manufacturer for normal operations. [R307-401-8] II.B.3.b.1 The parameters shall be monitored with instruments located such that an inspector/operator can
safely read the output any time. [R307-401-8]

II.B.3.c The owner/operator shall record both the pressure drop and liquid flow rate at least once per operating day while each scrubber is operating. [R307-401-8]
II.B.3.c.1 The owner/operator shall maintain the following records of the pressure drop and liquid flow rate:

A. Unit identification;
B. Manufacturer recommended pressure drop and liquid flow rate range;
C. Daily pressure drop and liquid flow rate readings;

D. Date of reading.
[R307-401-8]

II.B.3.d At least once every 12 months, the owner/operator shall calibrate each instrument in accordance with the manufacturer's instructions or replace the instrument. [R307-401-8]
II.B.3.d.1 The owner/operator shall maintain records of each instrument calibrations and replacements.
[R307-401-8]

II.B.3.e The owner/operator shall install a scrubber (ID# 761) that is certified to meet a NOx emission reduction of no less than 24%. [R307-401-8]
II.B.3.e.1 To demonstrate compliance with the above condition, the owner/operator shall maintain records
of the manufacturer's emissions guarantee for the installed scrubber. [R307-401-8]

DAQE-AN103670031-24
Page 11

II.B.4 Emergency Engine Requirements II.B.4.a The owner/operator shall certify that the 850 hp (550 kW) natural gas-fired, emergency engine
installed on site has a NOx emission rate of 0.40 grams per horsepower hour (g/hp-hr) or less, a CO emission rate of 0.7 g/hp-hr or less, and a VOC emission rate of 0.7 g/hp-hr or less at the exhaust point. [R307-401-8]

II.B.4.a.1 To demonstrate compliance with the above condition, the owner/operator shall either: A. Purchase a stationary internal combustion engine which has obtained certification as defined in 40 CFR 1039.801; or B. Conduct an initial performance test according to 40 CFR part 1039. C. Maintain the manufacturer's emissions guarantee for the installed engine model. [R307-401-8]
II.B.4.b The owner/operator 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. [40 CFR 63 Subpart ZZZZ, R307-401-8]

II.B.4.b.1 To determine compliance with a rolling 12-month total, the owner/operator shall calculate a new 12-month total by the 20th day of each month using data from the previous 12 months. 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. [40 CFR 63 Subpart ZZZZ, R307-401-8]
II.B.4.c The owner/operator shall only use natural gas as fuel in each emergency engine. [R307-401-8]

PERMIT HISTORY

This Approval Order shall supersede (if a modification) or will be based on the following documents:
Supersedes AO DAQE-AN103670030-24 dated June 26, 2024 Is Derived From NOI dated July 26, 2024
DAQE-AN103670031-24
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-IN103670031-24

August 29, 2024

Stewart Hogan
Asahi Refining USA, Inc.
4601 West 2100 South
West Valley City, UT 84120
[e-mail]

Dear Mr. Hogan:

Re: Intent to Approve: Modification to Approval Order DAQE-AN103670030-24 to Add One (1)
Emergency Engine and One (1) Electric Furnace
Project Number: N103670031

The attached document is the Intent to Approve (ITA) for the above-referenced project. The ITA is
subject to public review. Any comments received shall be considered before an Approval Order (AO) is
issued. The Division of Air Quality is authorized to charge a fee for reimbursement of the actual costs
incurred in the issuance of an AO. An invoice will follow upon issuance of the final AO.

Future correspondence on this ITA should include the engineer's name, Christine Bodell, as well as the
DAQE number as shown on the upper right-hand corner of this letter. Christine Bodell, can be reached at
[phone] or [e-mail], if you have any questions.

Sincerely,

{{$s }}

Alan D. Humpherys, Manager
New Source Review Section

ADH:CB:jg

cc: Salt Lake 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

STATE OF UTAH
Department of Environmental Quality
Division of Air Quality

INTENT TO APPROVE
DAQE-IN103670031-24
Modification to Approval Order DAQE-AN103670030-24 to Add
One (1) Emergency Engine and One (1) Electric Furnace

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

Issued to
Asahi Refining USA, Inc. - Precious Metals Refinery

Issued On
August 29, 2024

{{$s }}

New Source Review Section Manager
Alan D. Humpherys
{{#s=Sig_es_:signer1:signature}}

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 ................................................................................................. 3
Project Description.................................................................................................................. 4
SUMMARY OF EMISSIONS .................................................................................................... 4
PUBLIC NOTICE STATEMENT............................................................................................... 4
SECTION I: GENERAL PROVISIONS .................................................................................... 5
SECTION II: PERMITTED EQUIPMENT .............................................................................. 6
SECTION II: SPECIAL PROVISIONS ..................................................................................... 8
PERMIT HISTORY ................................................................................................................... 11
ACRONYMS ............................................................................................................................... 12

DAQE-IN103670031-24
Page 3

GENERAL INFORMATION

CONTACT/LOCATION INFORMATION

Owner Name Source Name
Asahi Refining USA, Inc. Asahi Refining USA, Inc. - Precious Metals Refinery

Mailing Address Physical Address
4601 West 2100 South 4601 West 2100 South
West Valley City, UT 84120 West Valley City, UT 84120

Source Contact UTM Coordinates
Name: Stewart Hogan 415,495 m Easting
Phone: [phone],508,700 m Northing
Email: [e-mail] Datum NAD83
UTM Zone 12
SIC code 3339 (Primary Smelting & Refining of Nonferrous Metals, Except Copper & Aluminum)

SOURCE INFORMATION
General Description
Asahi Refining USA, Inc. (Asahi) currently operates a precious metals refinery in West Valley City, Salt
Lake County. Mined doré and scrap are melted and tested for purity using small electric induction
furnaces, and then separated depending on gold and silver content. Separation is achieved by using
various inorganic chemicals and electrolytic methods. Silver is poured into anode molds and then placed
into the electrolytic cells. The cells contain silver nitrate solution, and the low voltage current causes
silver crystal to form onto a cathode plate. The silver crystal is scraped off and collected.
NSR Classification
Minor Modification at Minor Source

Source Classification
Located in Northern Wasatch Front O3 NAA, Salt Lake City UT PM2.5 NAA, Salt Lake County SO2
NAA
Salt Lake County
Airs Source Size: B

Applicable Federal Standards
NSPS (Part 60), A: General Provisions
NSPS (Part 60), JJJJ: Standards of Performance for Stationary Spark Ignition Internal
Combustion Engines
MACT (Part 63), A: General Provisions
MACT (Part 63), ZZZZ: National Emissions Standards for Hazardous Air Pollutants for
Stationary Reciprocating Internal Combustion Engines
DAQE-IN103670031-24
Page 4

Project Description
Asahi has requested to add one (1) new electric tilt furnace. The new electric tilt furnaces will have the
same control technologies as the existing electric tilt furnaces: a nanofilter baghouse made by UAS or the
combination of the venturi scrubber, WESP II, and scrubber #359. Asahi is not requesting to increase any
production and/or operational limits. No emissions are increasing as a result of the new electric furnace.
Equipment ID # II.A.15 has been updated to reflect the additional electric tilt furnace.

Asahi is also requested to add one (1) EPA-certified, 850 horsepower (550 kW) natural gas-fired
emergency generator engine to provide power to the existing scrubbers and other critical equipment
during a loss of line power.

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)
Ammonia 0 0.06
CO2 Equivalent 0 994.70
Carbon Monoxide 0.07 0.80
Lead 0 0.01
Nitrogen Oxides 0.04 4.35
Particulate Matter - PM10 0 2.01
Particulate Matter - PM2.5 0 2.01
Sulfur Dioxide 0 6.11
Volatile Organic Compounds 0.07 0.16

Hazardous Air Pollutant Change (lbs/yr) Total (lbs/yr)
Chlorine (CAS #7782505) 0 800
Formaldehyde (CAS #50000) 31
Generic HAPs (CAS #GHAPS) 10
Hexane (CAS #110543) 0 20
Hydrochloric Acid (Hydrogen Chloride) (CAS #7647010) 0 1600
Lead (CAS #7439921) 0 20
Selenium & Compounds (CAS #253) 0 60
Change (TPY) Total (TPY)
Total HAPs 0.02 1.27

PUBLIC NOTICE STATEMENT

The NOI for the above-referenced project has been evaluated and has been found to be consistent with the requirements of UAC R307. Air pollution producing sources and/or their air control facilities may not be
constructed, installed, established, or modified prior to the issuance of an AO by the Director.
A 30-day public comment period will be held in accordance with UAC R307-401-7. A notification of the
intent to approve will be published in the Salt Lake Tribune and Deseret News on September 1, 2024.
During the public comment period the proposal and the evaluation of its impact on air quality will be available for the public to review and provide comment. If anyone so requests a public hearing within 15
DAQE-IN103670031-24
Page 5
days of publication, it will be held in accordance with UAC R307-401-7. The hearing will be held as
close as practicable to the location of the source. Any comments received during the public comment period and the hearing will be evaluated. The proposed conditions of the AO may be changed as a result of the comments received.

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.

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] I.8 The owner/operator shall submit documentation of the status of construction or modification to the Director within 18 months from the date of this AO. This AO may become invalid if construction is not commenced within 18 months from the date of this AO 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. [R307-401-18]

DAQE-IN103670031-24
Page 6

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.
II.A THE APPROVED EQUIPMENT II.A.1 Metal Refinery Precious Metals Refinery Plant
II.A.2 Wastewater Treatment Wastewater effluent treatment. Process controlled by scrubber #760 II.A.3 Electrolytic Cells Silver electrolytic cell (refining of silver). Process controlled by scrubber #761.
II.A.4 Electrolytic Cells Gold electrolytic cell (refining of gold). Process controlled by scrubber #359. II.A.5 Wet Circuit Gold refinery wet circuits (part of the gold refining process). Process controlled by scrubber #359.
II.A.6 Chlorination Gold chloride electrolytic production (refining of gold). Process controlled by scrubber #359. II.A.7 Slime Washing Silver anode slime washing process (recovery of gold). Process controlled by scrubber #248.
II.A.8 Wet Chlorides Treatment Hydrometallurgical process for silver chloride sludge processing (recovery of gold). Controlled by scrubber #359. II.A.9 Fabric-Filter Baghouse Four (4) fabric-filter baghouses One baghouse controls emissions from the sweeps preparation process. Two baghouses control emissions from the melt room furnaces, the electric tilt furnaces, and the electric push-out furnaces. One baghouse controls the ashing furnace (Item II.A.26).
II.A.10 Boiler One (1) boiler, natural gas-fueled, rated less than 5 MMBtu/hr II.A.11 Dust Collector Dust collector for welding fume and grinding dust control in the maintenance shop
II.A.12 Electrostatic Precipitator One (1) wet-electrostatic precipitator (ID: WESP II) II.A.13 Chlorination Furnaces Four (4) electric-induction chlorination furnaces. Process controlled by venturi scrubber, WESP II, and scrubber #359.
DAQE-IN103670031-24
Page 7

II.A.14 Melt Furnaces Two (2) melt-room furnaces, natural gas-fueled, rated less than 5 MMBtu/hr each. Process controlled by a nanofilter baghouse made by UAS or the combination of the venturi scrubber, WESP II, and scrubber #359.
II.A.15 Tilt Furnaces (One (1) New) Nine (9) electric-tilt furnaces. Process controlled by a nanofilter baghouse made by UAS or the combination of the venturi scrubber, WESP II, and scrubber #359.

II.A.16 Push-out Furnaces Four (4) electric push-out furnaces. Process controlled by baghouse or the combination of the venturi scrubber, WESP II, and scrubber #359. II.A.17 Combustion Afterburner One (1) incinerator, natural gas-fueled, rated less than 5 MMBtu/hr

II.A.18 Nitrate Plant Silver nitrate plant (recovery of silver). Process controlled by scrubber #248.
II.A.19 Slime Plant Slime plant (recovery of gold). Process controlled by scrubber #248.

II.A.20 Drying Cabinets Five (5) electric drying cabinets. Process controlled by the combination of the venturi scrubber, WESP II, and scrubber #359.
II.A.21 Drying Cabinet One (1) drying cabinet, natural gas-fueled, rated less than 5 MMBtu/hr.

II.A.22 Wet Scrubbers Four (4) packed bed wet scrubbers (ID: 760, 359, 248, 761)
II.A.23 Venturi Scrubber
One (1) venturi scrubber is attached to WESP II as a pre-scrubber.
II.A.24 Tank System Silver reduction tanks (recovery of silver). Process controlled by scrubber #248. II.A.25 Ashing Furnace
One (1) dental scrap-ashing furnace. Process controlled by baghouse (Item II.A.9) and activated
carbon adsorption system (Item II.A.27).
II.A.26 Activated Carbon Adsorption System One (1) activated carbon adsorption system controls the ashing furnace (Item II.A.26)
II.A.27 Emergency Generator Engine
Rating: 60 kW
Manufacture Year: Pre-2006
Fuel: Natural Gas

NSPS Subpart Applicability: None
MACT Subpart Applicability: Subpart ZZZZ

DAQE-IN103670031-24
Page 8

II.A.28 Emergency Engine Rating: 850 hp (550 kW) Manufacture Year: 2022 Fuel: Natural Gas NSPS Subpart Applicability: Subpart JJJJ MACT Subpart Applicability: Subpart ZZZZ

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. II.B REQUIREMENTS AND LIMITATIONS
II.B.1 Site-Wide Requirements II.B.1.a The owner/operator shall not allow visible emissions from the following emission points to exceed the following values: A. All fabric filter baghouse exhaust stacks - 10%. B. All electrostatic precipitator exhaust stacks - 10%. C. All scrubber exhaust stacks - 10%. D. All incinerator exhaust stacks - 10%. E. All boiler exhaust stacks - 10%. F. All other points - 20%. [R307-401-8]
II.B.1.a.1 Opacity observations of emissions from stationary sources shall be conducted according to 40 CFR 60, Appendix A, Method 9. [R307-401-8] II.B.1.b The owner/operator shall not produce more than the following: A. 12,000,000 troy ounces of gold per rolling 12-month period. B. 60,000,000 troy ounces of silver per rolling 12-month period. C. 400 tons of sweeps per rolling 12-month period. [R307-401-8]
DAQE-IN103670031-24
Page 9

II.B.1.b.1 The owner/operator shall: A. Determine gold, silver, and sweeps production by company production records. B. Record gold and silver production on a daily basis and record sweeps production on a monthly basis. C. Use the gold and silver production data to calculate a new rolling 12-month total by the 20th day of each month using data from the previous 12 months. D. Use the sweeps production data to calculate a new rolling 12-month total by the 20th day of January, April, July, and October of each year using data from the previous 12 months. E. Keep the gold, silver, and sweeps production records for all periods the plant is in operation. [R307-401-8]
II.B.2 Baghouse Requirements
II.B.2.a The owner/operator shall use baghouses to control particulate emissions from the sweeps preparation process, melt room furnaces, electric tilt furnaces, electric push-out furnaces, and the ashing furnace. [R307-401-8]
II.B.2.b The owner/operator shall install a manometer or magnehelic pressure gauge to measure the static pressure differential across each baghouse. [R307-401-8]

II.B.2.b.1 The pressure gauge shall be located such that an inspector/operator can safely read the indicator at any time. [R307-401-8]
II.B.2.b.2 The pressure gauge shall measure the static pressure differential in 1-inch water column
increments or less. [R307-401-8]
II.B.2.c During the operation of each baghouse, the owner/operator shall maintain the static pressure differential within the range recommended by the manufacturer for normal operations. [R307-401-8]
II.B.2.c.1 The owner/operator shall record the static pressure differential at least once per operating day
while each baghouse is operating. [R307-401-8]
II.B.2.c.2 The owner/operator shall maintain the following records of the static pressure differential: A. Unit identification; B. Manufacturer-recommended static pressure differential range for the unit; C. Daily static pressure differential readings; D. Date of reading. [R307-401-8]
II.B.2.d At least once every 12 months, the owner/operator shall calibrate each pressure gauge in
accordance with the manufacturer's instructions or replace the pressure gauge. [R307-401-8]

II.B.2.d.1 The owner/operator shall maintain records of each pressure gauge calibrations and replacements. [R307-401-8]
DAQE-IN103670031-24
Page 10

II.B.3 Wet Scrubber Requirements II.B.3.a The owner/operator shall use the following scrubbers to control the following process streams:
Scrubber Process Stream Scrubber #248 silver anode slime washing process, silver nitrate plant, and slime
plant Scrubber #359 gold electrolytic cells, gold refinery wet circuits, gold chloride
electrolytic production, silver chlorides sludge processing, chlorination furnaces, melt furnaces, tilt furnaces, push-out furnaces, and drying cabinets
Scrubber #760 wastewater treatment tanks and laboratory
Scrubber #761 silver electrolytic cells
All exhaust air from the above-mentioned process streams shall be routed through the indicated
scrubber before being vented to the atmosphere.
[R307-401-8]

II.B.3.b During operation of each scrubber, the owner/operator shall maintain both the pressure drop and the liquid flow rate within the respective range recommended by the manufacturer for normal operations. [R307-401-8] II.B.3.b.1 The parameters shall be monitored with instruments located such that an inspector/operator can
safely read the output any time. [R307-401-8]

II.B.3.c The owner/operator shall record both the pressure drop and liquid flow rate at least once per operating day while each scrubber is operating. [R307-401-8]
II.B.3.c.1 The owner/operator shall maintain the following records of the pressure drop and liquid flow rate:

A. Unit identification;
B. Manufacturer recommended pressure drop and liquid flow rate range;
C. Daily pressure drop and liquid flow rate readings;

D. Date of reading.
[R307-401-8]

II.B.3.d At least once every 12 months, the owner/operator shall calibrate each instrument in accordance with the manufacturer's instructions or replace the instrument. [R307-401-8]
II.B.3.d.1 The owner/operator shall maintain records of each instrument’s calibrations and replacements.
[R307-401-8]

II.B.3.e The owner/operator shall install a scrubber (ID# 761) that is certified to meet a NOx emission reduction of no less than 24%. [R307-401-8]
II.B.3.e.1 To demonstrate compliance with the above condition, the owner/operator shall maintain records
of the manufacturer's emissions guarantee for the installed scrubber. [R307-401-8]

DAQE-IN103670031-24
Page 11

II.B.4 Emergency Engine Requirements II.B.4.a The owner/operator shall certify that the 850 hp (550 kW) natural gas-fired, emergency engine
installed on site has a NOx emission rate of 0.40 grams per horsepower hour (g/hp-hr) or less, a CO emission rate of 0.7 g/hp-hr or less, and a VOC emission rate of 0.7 g/hp-hr or less at the exhaust point. [R307-401-8]

II.B.4.a.1 To demonstrate compliance with the above condition, the owner/operator shall either: A. Purchase a stationary internal combustion engine which has obtained certification as defined in 40 CFR 1039.801; or B. Conduct an initial performance test according to 40 CFR Part 1039. C. Maintain the manufacturer's emissions guarantee for the installed engine model. [R307-401-8]
II.B.4.b The owner/operator 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. [40 CFR 63 Subpart ZZZZ, R307-401-8]

II.B.4.b.1 To determine compliance with a rolling 12-month total, the owner/operator shall calculate a new 12-month total by the 20th day of each month using data from the previous 12 months. 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. [40 CFR 63 Subpart ZZZZ, R307-401-8]
II.B.4.c The owner/operator shall only use natural gas as fuel in each emergency engine. [R307-401-8]

PERMIT HISTORY

This Approval Order shall supersede (if a modification) or will be based on the following documents:
Supersedes AO DAQE-AN103670030-24 dated June 26, 2024 Is Derived From NOI dated July 26, 2024
DAQE-IN103670031-24
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

The Salt Lake Tribune
Publication Name:
The Salt Lake Tribune
Publication URL:
Publication City and State:
Salt Lake City, UT
Publication County:
Salt Lake
Notice Popular Keyword Category:
Notice Keywords:
asahi
Notice Authentication Number:
202409031007427971237
1761527914
Notice URL:
Back
Notice Publish Date:
Sunday, September 01, 2024
Notice Content
NOTICE A Notice of Intent for the following project submitted in accordance with R307-401-1, Utah Administrative Code (UAC), has been
received for consideration by the Director: Company Name: Asahi Refining USA, Inc. Location: Asahi Refining USA, Inc. - Precious Metals
Refinery – 4601 West 2100 South, West Valley City, UT Project Description: Asahi Refining USA, Inc. (Asahi) currently operates a precious
metals refinery in West Valley City, Salt Lake County. Mined doré and scrap are melted and tested for purity using small electric induction
furnaces, and then separated depending on gold and silver content. Separation is achieved by using various inorganic chemicals and
electrolytic methods. Silver is poured into anode molds and then placed into the electrolytic cells. The cells contain silver nitrate solution, and
the low voltage current causes silver crystal to form onto a cathode plate. The silver crystal is scraped off and collected. Asahi has requested
to add one (1) new electric tilt furnace. The new electric tilt furnaces will have the same control technologies as the existing electric tilt
furnaces: a nanofilter baghouse made by UAS or the combination of the venturi scrubber, WESP II, and scrubber #359. Asahi is not
requesting to increase any production and/or operational limits. No emissions are increasing as a result of the new electric furnace.
Equipment ID # II.A.15 has been updated to reflect the additional electric tilt furnace. Asahi is also requested to add one (1) EPA-certified,
850 horsepower (550 kW) natural gas-fired emergency generator engine to provide power to the existing scrubbers and other critical
equipment during a loss of line power. The completed engineering evaluation and air quality impact analysis showed the proposed project
meets the requirements of federal air quality regulations and the State air quality rules. The Director intends to issue an Approval Order
pending a 30-day public comment period. The project proposal, estimate of the effect on local air quality and draft Approval Order are
available for public inspection and comment at the Utah Division of Air Quality, 195 North 1950 West, Salt Lake City, UT 84116. Written
comments received by the Division at this same address on or before October 1, 2024, will be considered in making the final decision on the
approval/disapproval of the proposed project. Email comments will also be accepted at [e-mail]. If anyone so requests to the
Director in writing within 15 days of publication of this notice, a hearing will be held in accordance with R307-401-7, UAC. Under Section 19-
1-301.5, a person who wishes to challenge a Permit Order may only raise an issue or argument during an adjudicatory proceeding that was
raised during the public comment period and was supported with sufficient information or documentation to enable the Director to fully
consider the substance and significance of the issue. Date of Notice: September 1, 2024 SLT0029156
Back

DAQE-NN103670031-24

August 29, 2024

Salt Lake Tribune and Deseret News
Legal Advertising Dept.
P.O. Box 704055
West Valley City, UT 84170
Acct #9001399880

RE: Legal Notice of Intent to Approve

This letter will confirm the authorization to publish the attached NOTICE in the Salt Lake Tribune and
Deseret News on September 1, 2024.

Please mail the invoice and affidavit of publication to the Utah State Department of Environmental
Quality, Division of Air Quality, P.O. Box 144820, Salt Lake City, Utah 84114-4820. If you have any
questions, contact Jeree Greenwood, who may be reached at [phone].

Sincerely,

{{$s }}

Jeree Greenwood
Office Technician

Enclosure

cc: Salt Lake County
cc: Wasatch Front Regional Council

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

DAQE-NN103670031-24
Page 2
NOTICE

A Notice of Intent for the following project submitted in accordance with R307-401-1, Utah
Administrative Code (UAC), has been received for consideration by the Director:

Company Name: Asahi Refining USA, Inc.
Location: Asahi Refining USA, Inc. - Precious Metals Refinery – 4601 West 2100 South,
West Valley City, UT
Project Description: Asahi Refining USA, Inc. (Asahi) currently operates a precious metals refinery in
West Valley City, Salt Lake County. Mined doré and scrap are melted and tested
for purity using small electric induction furnaces, and then separated depending
on gold and silver content. Separation is achieved by using various inorganic
chemicals and electrolytic methods. Silver is poured into anode molds and then
placed into the electrolytic cells. The cells contain silver nitrate solution, and the
low voltage current causes silver crystal to form onto a cathode plate. The silver
crystal is scraped off and collected.

Asahi has requested to add one (1) new electric tilt furnace. The new electric tilt
furnaces will have the same control technologies as the existing electric tilt
furnaces: a nanofilter baghouse made by UAS or the combination of the venturi
scrubber, WESP II, and scrubber #359. Asahi is not requesting to increase any
production and/or operational limits. No emissions are increasing as a result of
the new electric furnace. Equipment ID # II.A.15 has been updated to reflect the
additional electric tilt furnace.

Asahi is also requested to add one (1) EPA-certified, 850 horsepower (550 kW)
natural gas-fired emergency generator engine to provide power to the existing
scrubbers and other critical equipment during a loss of line power.

The completed engineering evaluation and air quality impact analysis showed the proposed project meets
the requirements of federal air quality regulations and the State air quality rules. The Director intends to
issue an Approval Order pending a 30-day public comment period. The project proposal, estimate of the
effect on local air quality and draft Approval Order are available for public inspection and comment at the
Utah Division of Air Quality, 195 North 1950 West, Salt Lake City, UT 84116. Written comments
received by the Division at this same address on or before October 1, 2024, will be considered in making
the final decision on the approval/disapproval of the proposed project. Email comments will also be
accepted at [e-mail]. If anyone so requests to the Director in writing within 15 days of
publication of this notice, a hearing will be held in accordance with R307-401-7, UAC.

Under Section 19-1-301.5, a person who wishes to challenge a Permit Order may only raise an issue or
argument during an adjudicatory proceeding that was raised during the public comment period and was
supported with sufficient information or documentation to enable the Director to fully consider the
substance and significance of the issue.

Date of Notice: September 1, 2024

{{#s=Sig_es_:signer1:signature}}

DAQE-

RN103670031 August 15, 2024 Stewart Hogan Asahi Refining USA, Inc. 4601 West 2100 South West Valley City, UT 84120
[e-mail] Dear Stewart Hogan,
Re: Engineer Review: Modification to Approval Order DAQE-AN103670030-24 to Add One (1) Emergency Engine
and One (1) Electric Furnace Project Number: N103670031
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 permitting program. Asahi Refining USA, Inc. should complete this review within 10 business days of receipt.
Asahi Refining USA, 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 ITA for a 30-day public comment period. At the completion of the comment period, the DAQ will address any comments and will prepare an Approval Order (AO) for signature by the DAQ Director.
If Asahi Refining USA, Inc. does not respond to this letter within 10 business days, the project will move forward without source concurrence. If Asahi Refining USA, 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 N103670031: Asahi Refining USA, Inc.- Precious Metals Refinery August 15, 2024 Page 1
UTAH DIVISION OF AIR QUALITY
ENGINEER REVIEW

SOURCE INFORMATION
Project Number N103670031 Owner Name Asahi Refining USA, Inc. Mailing Address 4601 West 2100 South West Valley City, UT, 84120 Source Name Asahi Refining USA, Inc.- Precious Metals Refinery Source Location 4601 West 2100 South West Valley City, UT 84120
UTM Projection 415,495 m Easting, 4,508,700 m Northing UTM Datum NAD83 UTM Zone UTM Zone 12
SIC Code 3339 (Primary Smelting & Refining of Nonferrous Metals, Except Copper & Aluminum)
Source Contact Stewart Hogan Phone Number [phone] Email [e-mail]
Billing Contact Stewart Hogan Phone Number 801-924-6089 Email [e-mail] Project Engineer Christine Bodell, Engineer Phone Number [phone] Email [e-mail]
Notice of Intent (NOI) Submitted July 26, 2024 Date of Accepted Application July 31, 2024

Engineer Review N103670031: Asahi Refining USA, Inc.- Precious Metals Refinery August 15, 2024 Page 2
SOURCE DESCRIPTION General Description
Asahi Refining USA, Inc. (Asahi) currently operates a precious metals refinery in West Valley City, Salt Lake County. Mined doré and scrap are melted and tested for purity using small electric induction furnaces and then separated depending on gold and silver content. Separation is
achieved by using various inorganic chemicals and electrolytic methods. Silver is poured into anode molds and then placed into the electrolytic cells. The cells contain silver nitrate solution, and the low voltage current causes silver crystal to form onto a cathode plate. The silver crystal is
scraped off and collected. NSR Classification:
Minor Modification at Minor Source Source Classification
Located in , Northern Wasatch Front O3 NAA, Salt Lake City UT PM2.5 NAA, Salt Lake County SO2 NAA, Salt Lake County Airs Source Size: B Applicable Federal Standards NSPS (Part 60), A: General Provisions NSPS (Part 60), JJJJ: Standards of Performance for Stationary Spark Ignition Internal
Combustion Engines MACT (Part 63), A: General Provisions MACT (Part 63), ZZZZ: National Emissions Standards for Hazardous Air Pollutants for
Stationary Reciprocating Internal Combustion Engines Project Proposal
Modification to Approval Order DAQE-AN103670030-24 to Add One (1) Emergency Engine and One (1) Electric Furnace
Project Description Asahi Refining Inc. (Asahi) has requested to add one (1) new electric tilt furnace. The new electric tilt furnaces will have the same control technologies as the existing electric tilt furnaces: a
nanofilter baghouse made by UAS or the combination of the venturi scrubber, WESP II, and scrubber #359. Asahi is not requesting to increase any production and/or operational limits. No emissions are increasing as a result of the new electric furnace. Equipment ID # II.A.15 has been updated to reflect the additional electric tilt furnace. Asahi is also requested to add one (1) EPA-certified, 850 horsepower (550 kW) natural gas-fired emergency generator engine to provide power to the existing scrubbers and other critical equipment during a loss of line power.
EMISSION IMPACT ANALYSIS Asahi does not meet the criteria pollutant modeling thresholds outlined in R307-410-4 or the HAPs thresholds outlined in R307-410-5. Therefore, modeling is not required. [Last updated July 29, 2024]

Engineer Review N103670031: Asahi Refining USA, Inc.- Precious Metals Refinery August 15, 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) Ammonia 0 0.06
CO2 Equivalent 0 994.70
Carbon Monoxide 0.07 0.80
Lead 0 0.01
Nitrogen Oxides 0.04 4.35
Particulate Matter - PM10 0 2.01 Particulate Matter - PM2.5 0 2.01 Sulfur Dioxide 0 6.11
Volatile Organic Compounds 0.07 0.16

Hazardous Air Pollutant Change (lbs/yr) Total (lbs/yr)
Chlorine (CAS #7782505) 0 800
Formaldehyde (CAS #50000) 31 Generic HAPs (CAS #GHAPS) 10 Hexane (CAS #110543) 0 20
Hydrochloric Acid (Hydrogen Chloride) (CAS #7647010) 0 1600
Lead (CAS #7439921) 0 20
Selenium & Compounds (CAS #253) 0 60
Change (TPY) Total (TPY)
Total HAPs 0.02 1.27 Note: Change in emissions indicates the difference between previous AO and proposed modification.

Engineer Review N103670031: Asahi Refining USA, Inc.- Precious Metals Refinery August 15, 2024 Page 4
Review of BACT for New/Modified Emission Units 1. BACT review regarding New Electric Tilt Furnace
All the existing electric tilt furnaces on site are controlled by a nanofilter baghouse made by UAS or the combination of the venturi scrubber, WESP II, and scrubber #359. The new electric tilt furnace is used for producing silver grain. Silver production limits are not increasing. Additionally,
the new equipment will operate under existing emissions limitations and be controlled by a nanofilter baghouse made by UAS or the combination of the venturi scrubber, WESP II, and scrubber #359. This is considered BACT. [Last updated July 31, 2024]
2. BACT review regarding New Natural Gas-Fired Emergency Engine The proposed emergency engine will result in less than 0.01 tpy each of NOx, CO, PM10, PM2.5,
VOCs, SO2, and HAPs. One way of reducing overall engine emissions is to install newer equipment that meets EPA's emission standards. 40 CFR 60 Subpart JJJJ requires owners and operators of emergency natural gas-fired engines manufactured after 2009 with a rating greater than 130 hp to meet the following
emissions standards: NOx - 2.0 g/hp-hr; CO - 4.0 g/hp-hr; VOC - 1.0 g/hp-hr. The source has elected to install an engine with the following emission rates: NOx - 0.4 g/hp-hr; CO - 0.7 g/hp-hr; VOC - 0.7 g/hp-hr. Each emission rate is lower than the rates required by NSPS Subpart JJJJ. The engine will not exceed 100 hours of operation per year for maintenance and testing purposes. The potential to emits are based on 100 hours of emergency use per engine. Due to the inconsistent
and low volume of air pollutants emitted from the engine during testing and maintenance, additional add-on controls such as use of an SCR (selective catalytic reduction) or OC (oxidation catalyst) system to control PM10, PM2.5, VOCs, and HAPs are cost prohibitive.
BACT for the engine is to limit visible emissions at or below 10% opacity. [Last updated July 31,
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]

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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]
I.8 The owner/operator shall submit documentation of the status of construction or modification
to the Director within 18 months from the date of this AO. This AO may become invalid if construction is not commenced within 18 months from the date of this AO 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. [R307-401-18]

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 Metal Refinery Precious Metals Refinery Plant

II.A.2 Wastewater Treatment Wastewater effluent treatment. Process controlled by scrubber #760
II.A.3 Electrolytic Cells Silver electrolytic cell (refining of silver). Process controlled by scrubber #761.
II.A.4 Electrolytic Cells Gold electrolytic cell (refining of gold). Process controlled by scrubber #359.

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II.A.5 Wet Circuit Gold refinery wet circuits (part of the gold refining process). Process controlled by scrubber #359.
II.A.6 Chlorination
Gold chloride electrolytic production (refining of gold). Process controlled by scrubber #359. II.A.7 Slime Washing Silver anode slime washing process (recovery of gold). Process controlled by scrubber #248.

II.A.8 Wet Chlorides Treatment Hydrometallurgical process for silver chlorides sludge processing (recovery of gold). Controlled by scrubber #359.
II.A.9 Fabric-Filter Baghouse
Four (4) fabric-filter baghouses One baghouse controls emissions from the sweeps preparation process. Two baghouses control emissions from the melt room furnaces, the electric tilt furnaces, and the electric push-out furnaces. One baghouse controls the ashing furnace (Item II.A.26).

II.A.10 Boiler One (1) boiler, natural gas-fueled, rated less than 5 MMBtu/hr
II.A.11 Dust Collector Dust collector for welding fume and grinding dust control in maintenance shop

II.A.12 Electrostatic Precipitator One (1) wet-electrostatic precipitator (ID: WESP II)
II.A.13 Chlorination Furnaces Four (4) electric-induction chlorination furnaces. Process controlled by venturi scrubber, WESP II, and scrubber #359. II.A.14 Melt Furnaces Two (2) melt-room furnaces, natural gas-fueled, rated less than 5 MMBtu/hr each. Process
controlled by a nanofilter baghouse made by UAS or the combination of the venturi scrubber, WESP II, and scrubber #359.
II.A.15 Tilt Furnaces (One New)
Nine (9) electric-tilt furnaces. Process controlled by a nanofilter baghouse made by UAS or the combination of the venturi scrubber, WESP II, and scrubber #359.
II.A.16 Push-out Furnaces Four (4) electric push-out furnaces. Process controlled by baghouse or the combination of the venturi scrubber, WESP II, and scrubber #359.
II.A.17 Combustion Afterburner One (1) incinerator, natural gas-fueled, rated less than 5 MMBtu/hr

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II.A.18 Nitrate Plant Silver nitrate plant (recovery of silver). Process controlled by scrubber #248. II.A.19 Slime Plant Slime plant (recovery of gold). Process controlled by scrubber #248.

II.A.20 Drying Cabinets Five (5) electric drying cabinets. Process controlled by the combination of the venturi scrubber, WESP II, and scrubber #359.

II.A.21 Drying Cabinet One (1) drying cabinet, natural gas-fueled, rated less than 5 MMBtu/hr. II.A.22 Wet Scrubbers Four (4) packed bed wet scrubbers (ID: 760, 359, 248, 761)

II.A.23 Venturi Scrubber One (1) venturi scrubber attached to WESP II as a pre-scrubber.
II.A.24 Tank System Silver reduction tanks (recovery of silver). Process controlled by scrubber #248.
II.A.25 Ashing Furnace One (1) dental scrap ashing furnace. Process controlled by baghouse (Item II.A.9) and activated carbon adsorption system (Item II.A.27).

II.A.26 Activated Carbon Adsorption System One (1) activated carbon adsorption system controls the ashing furnace (Item II.A.26)
II.A.27 Emergency Generator Engine Rating: 60 kW Manufacture Year: Pre-2006 Fuel: Natural Gas
NSPS Subpart Applicability: None MACT Subpart Applicability: Subpart ZZZZ

II.A.28 NEW Emergency Engine Rating: 850 hp (550 kW) Manufacture Year: 2022
Fuel: Natural Gas NSPS Subpart Applicability: Subpart JJJJ MACT Subpart Applicability: Subpart ZZZZ

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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 Requirements
II.B.1.a The owner/operator shall not allow visible emissions from the following emission points to
exceed the following values: A. All fabric filter baghouse exhaust stacks - 10% B. All electrostatic precipitator exhaust stacks - 10%
C. All scrubber exhaust stacks - 10%
D. All incinerator exhaust stacks - 10% E. All boiler exhaust stacks - 10%
F. All other points - 20% [R307-401-8] II.B.1.a.1 Opacity observations of emissions from stationary sources shall be conducted according to 40 CFR 60, Appendix A, Method 9. [R307-401-8]

II.B.1.b The owner/operator shall not produce more than the following:
A. 12,000,000 troy ounces of gold per rolling 12-month period
B. 60,000,000 troy ounces of silver per rolling 12-month period C. 400 tons of sweeps per rolling 12-month period [R307-401-8]

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II.B.1.b.1 The owner/operator shall:
A. Determine gold, silver, and sweeps production by company production records
B. Record gold and silver production on a daily basis and record sweeps production
on a monthly basis
C. Use the gold and silver production data to calculate a new rolling 12-month total by
the 20th day of each month using data from the previous 12 months D. Use the sweeps production data to calculate a new rolling 12-month total by the
20th day of January, April, July and October of each year using data from the
previous 12 months.
E. Keep the gold, silver, and sweeps production records for all periods the plant is in
operation.
[R307-401-8]

II.B.2 Baghouse Requirements
II.B.2.a The owner/operator shall use baghouses to control particulate emissions from the sweeps
preparation process, melt room furnaces, electric tilt furnaces, electric push-out furnaces, and the ashing furnace. [R307-401-8]
II.B.2.b The owner/operator shall install a manometer or magnehelic pressure gauge to measure the
static pressure differential across each baghouse. [R307-401-8] II.B.2.b.1 The pressure gauge shall be located such that an inspector/operator can safely read the indicator at any time. [R307-401-8]

II.B.2.b.2 The pressure gauge shall measure the static pressure differential in 1-inch water column
increments or less. [R307-401-8] II.B.2.c During operation of each baghouse, the owner/operator shall maintain the static pressure differential within the range recommended by the manufacturer for normal operations. [R307-
401-8] II.B.2.c.1 The owner/operator shall record the static pressure differential at least once per operating day while each baghouse is operating. [R307-401-8]

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II.B.2.c.2 The owner/operator shall maintain the following records of the static pressure differential:
A. Unit identification;
B. Manufacturer recommended static pressure differential range for the unit; C. Daily static pressure differential readings; D. Date of reading. [R307-401-8] II.B.2.d At least once every 12 months, the owner/operator shall calibrate each pressure gauge in accordance with the manufacturer's instructions or replace the pressure gauge. [R307-401-8]

II.B.2.d.1 The owner/operator shall maintain records of each pressure gauge calibrations and replacements. [R307-401-8] II.B.3 Wet Scrubber Requirements II.B.3.a NEW The owner/operator shall use the following scrubbers to control the following process streams. Scrubber Process Stream Scrubber #248 silver anode slime washing process, silver nitrate plant, and slime
plant
Scrubber #359 gold electrolytic cells, gold refinery wet circuits, gold chloride
electrolytic production, silver chlorides sludge processing,
chlorination furnaces, melt furnaces, tilt furnaces, push-out
furnaces, and drying cabinets
Scrubber #760 wastewater treatment tanks and laboratory Scrubber #761 silver electrolytic cells All exhaust air from the above-mentioned process streams shall be routed through the indicated scrubber before being vented to the atmosphere.
[R307-401-8]
II.B.3.b During operation of each scrubber, the owner/operator shall maintain both the pressure drop
and the liquid flow rate within the respective range recommended by the manufacturer for normal operations. [R307-401-8]
II.B.3.b.1 The parameters shall be monitored with instruments located such that an inspector/operator
can safely read the output any time. [R307-401-8]
II.B.3.c The owner/operator shall record both the pressure drop and liquid flow rate at least once per operating day while each scrubber is operating. [R307-401-8]

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II.B.3.c.1 The owner/operator shall maintain the following records of the pressure drop and liquid flow rate: A. Unit identification; B. Manufacturer recommended pressure drop and liquid flow rate range;
C. Daily pressure drop and liquid flow rate readings;
D. Date of reading.
[R307-401-8]
II.B.3.d At least once every 12 months, the owner/operator shall calibrate each instrument in
accordance with the manufacturer's instructions or replace the instrument. [R307-401-8] II.B.3.d.1 The owner/operator shall maintain records of each instrument calibrations and replacements. [R307-401-8]
II.B.3.e The owner/operator shall install a scrubber (ID# 761) that is certified to meet a NOx emission
reduction of no less than 24%. [R307-401-8] II.B.3.e.1 To demonstrate compliance with the above condition, the owner/operator shall maintain records of the manufacturer's emissions guarantee for the installed scrubber. [R307-401-8]

II.B.4 Emergency Engine Requirements
II.B.4.a
NEW
The owner/operator shall certify that the 850 hp (550 kW) natural gas-fired, emergency engine
installed on site has a NOx emission rate of 0.40 grams per horsepower hour (g/hp-hr) or less, a CO emission rate of 0.7 g/hp-hr or less, and a VOC emission rate of 0.7 g/hp-hr or less at the exhaust point. [R307-401-8]

II.B.4.a.1 NEW To demonstrate compliance with the above condition, the owner/operator shall either: A. Purchase a stationary internal combustion engine which has obtained certification
as defined in 40 CFR 1039.801; or B. Conduct an initial performance test according to 40 CFR part 1039. C. Maintain the manufacturer's emissions guarantee for the installed engine model.
[R307-401-8]

II.B.4.b NEW The owner/operator 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. [40 CFR 63 Subpart ZZZZ, R307-401-8]

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II.B.4.b.1 NEW To determine compliance with a rolling 12-month total, the owner/operator shall calculate a new 12-month total by the 20th day of each month using data from the previous 12 months. 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 [40 CFR 63 Subpart ZZZZ, R307-401-8]
II.B.4.c NEW The owner/operator shall only use natural gas as fuel in each emergency engine. [R307-401-8]

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PERMIT HISTORY When issued, the approval order shall supersede (if a modification) or will be based on the
following documents: Supersedes AO DAQE-AN103670030-24 dated June 26, 2024
Is Derived From NOI dated July 26, 2024
REVIEWER COMMENTS

2. Comment regarding NSPS and MACT Applicability: 40 CFR 60 Subpart JJJJ- Standards of Performance for Stationary Spark Ignition Internal Combustion Engines
The facility includes one (1) existing 60 kW, natural gas-fired emergency stationary engine and one (1) new 850 hp, natural gas-fired emergency engine. The provisions of this subpart are applicable to owners and operators of stationary SI ICE that commence construction after June 12, 2006, where
the stationary SI ICE are manufactured post-2006. The one (1) existing 60 kW, natural gas-fired emergency stationary engine was installed prior to June 12, 2006. Therefore, NSPS Subpart JJJJ does not apply to this engine. The new 850 hp, natural gas-fired emergency engine was manufactured in 2022 and is expected to be installed in 2024 or 2025. Therefore, NSPS Subpart JJJJ applies to this engine. 40 CFR 63 Subpart ZZZZ - National Emissions Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines
The provisions of this subpart are applicable to owners/operators of stationary RICE at a major or area sources of HAP emissions. The provisions of MACT Subpart ZZZZ apply as the stationary reciprocating internal combustion engine (RICE) is at an area source of HAP emissions. The facility
includes one (1) existing 60 kW, natural gas-fired emergency stationary engine and one (1) new 850 hp, natural gas-fired emergency engine. Each engine is not designated as nonroad and not exempt and is therefore an affected source under this regulation. Therefore, MACT Subpart ZZZZ applies to each engine. [Last updated July 31, 2024]
3. Comment regarding Title V Applicability: Title V of the 1990 CAA (Title V) applies to the following:
A. Any major source B. Any source subject to a standard, limitation, or other requirement under Section 111 of the Act, Standards of Performance for New Stationary Sources
C. Any source subject to a standard or other requirement under Section 112 of the Act, Hazardous Air Pollutants
D. 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 61 (NESHAP) standards, but is subject to 40 CFR 60 (NSPS) Subparts A and JJJJ and 40 CFR 63 (MACT). Subparts A and ZZZZ regulations. NSPS Subpart JJJJ and MACT Subpart ZZZZ each specifically exempts sources from the obligation to obtain a permit under 40 CFR part 70 (Title V

Engineer Review N103670031: Asahi Refining USA, Inc.- Precious Metals Refinery August 15, 2024 Page 14
permit) if the source is not otherwise required by law to obtain a permit. There are no other reasons why this source would be required to obtain a part 70 permit; therefore, Title V does not apply to this
facility. [Last updated August 15, 2024]

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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
Equipment Details
Rating 850 hp = (634.4 kw)
Operational Hours 100 hours/year
Engine Type
Criteria Pollutant
Emission
Standards
(g/hp-hr)
Emission Factor
(lb/MMBtu)
Emission
Rate
(lbs/hr)
Emission
Total
(tons/year)Reference
NOX 0.4 0.75 0.04
CO 0.7 1.31 0.07
PM10 9.99E-03 0.06 0.00
PM2.5 9.99E-03 0.06 0.00
VOC 1.18E-01 0.70 0.04
SO2 5.88E-04 0.00 0.00
HAP 0.43 0.02 See Below
Green House Gas Pollutant
Global
Warming
Potential
Emission Factor
(lb/MMBtu)
Emission
Rate
(lbs/hr)
Emission
Total
(tons/year)Reference
CO2 (mass basis)1 1.10E+02 655 33
Methane (mass basis)25 1.25E+00 7 0CO2e42
Hazardous Air Pollutant
Emission
Rate
(lbs/hr)
Emission
Total
(tons/year)Reference
1,1,2,2-Tetrachloroethane 4.00E-05 2.38E-04 1.19E-05
1,1,2-Trichloroethane 3.18E-05 1.89E-04 9.46E-06
1,3-Butadiene 2.67E-04 1.59E-03 7.94E-05
1,3-Dichloropropene 2.64E-05 1.57E-04 7.85E-06
2,2,4-Trimethylpentane 2.50E-04 1.49E-03 7.44E-05
2-Methylnaphthalene 3.32E-05 1.98E-04 9.88E-06
Acenaphthene 1.25E-06 7.44E-06 3.72E-07
Acenaphthylene 5.53E-06 3.29E-05 1.65E-06
Acetaldehyde 8.36E-03 4.97E-02 2.49E-03
Acrolein 5.14E-03 3.06E-02 1.53E-03
Benzene 4.40E-04 2.62E-03 1.31E-04
Benzo(b)fluoranthene 1.66E-07 9.88E-07 4.94E-08
Benzo(e)pyrene 4.15E-07 2.47E-06 1.23E-07
benzo(g,h,i)perylene 4.14E-07 2.46E-06 1.23E-07
Biphenyl 2.12E-04 1.26E-03 6.31E-05
Carbon Tetrachloride 3.67E-05 2.18E-04 1.09E-05
Chlorobenzene 3.04E-05 1.81E-04 9.04E-06
Chloroform 2.85E-05 1.70E-04 8.48E-06
Chrysene 6.93E-07 4.12E-06 2.06E-07
Ethylbenzene 3.97E-05 2.36E-04 1.18E-05
Ethylene Dibromide 4.43E-05 2.64E-04 1.32E-05
Fluoranthene 1.11E-06 6.60E-06 3.30E-07
Fluorene 5.67E-06 3.37E-05 1.69E-06
Formaldehyde 5.28E-02 3.14E-01 1.57E-02
Methanol 2.50E-03 1.49E-02 7.44E-04
Methylene Chloride 2.00E-05 1.19E-04 5.95E-06
n-Hexane 1.11E-03 6.60E-03 3.30E-04
Naphthalene 7.44E-05 4.43E-04 2.21E-05
PAH 2.69E-05 1.60E-04 8.00E-06
Phenanthrene 1.04E-05 6.19E-05 3.09E-06
Phenol 2.40E-05 1.43E-04 7.14E-06
Pyrene 1.36E-06 8.09E-06 4.05E-07
Styrene 2.36E-05 1.40E-04 7.02E-06
Tetrachloroethane 2.48E-06 1.48E-05 7.38E-07
Toluene 4.08E-04 2.43E-03 1.21E-04
Vinyl Chloride 1.49E-05 8.87E-05 4.43E-06Xylene1.84E-04 1.09E-03 5.47E-05
Emission Factor
(lb/MMBtu)
Natural Gas-Fired Engines
AP-42 Table 3.2-1,
Table 3.2-2, &
Table 3.2-3
AP-42 Table 3.2-1,
Table 3.2-2, &
Table 3.2-3
(Some HAP do not
popluate based on
the type of engine
selected. AP-42 does
not list certain HAP
for certain types of
engines.)
Manufacturer Data,
AP-42 Table 3.2-1,
Table 3.2-2, &
Table 3.2-3
4-Stroke Lean-Burn
Emergency Engines should
equal 100 hours of
operation per year
Page 1 of 1 Version 1.1
February 21, 2019