DAQ-2025-001767

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DAQC-297-25
Site ID 11408 (B1)

MEMORANDUM

TO: FILE – TEXAS INSTRUMENTS

THROUGH: Harold Burge, Major Source Compliance Section Manager

FROM: Jeremiah R. Marsigli, Environmental Scientist

DATE: March 21, 2025

SUBJECT: FULL COMPLIANCE EVALUATION, Major, Utah County,
FRS ID# UT0000004904900177

INSPECTION DATE: March 13, 2025

SOURCE LOCATION: 4000 North Flash Drive, Lehi, UT 84043-3175

MAILING ADDRESS: 4000 North Flash Drive, Lehi, UT 84043-3175

SOURCE CONTACT(S): Mark Illum, Environmental Engineer: [phone]

OPERATING STATUS: Operating normally

PROCESS DESCRIPTION:

Texas Instruments manufactures solid-state electronic devices, mainly semi conductors. The basic
production elements of fabrication are utilized. The source operates with additional support services such
as steam generation boilers, emergency back-up generators, and wastewater treatment.

Fabrication: Sliced silicon wafers are shipped to the source in transport trucks. The wafers are chemically
cleaned to remove any particles or contaminants. The cleaning solvent is an acid and is controlled by an
acid scrubber. Any final acid waste is cycled through the facility industrial wastewater treatment system.

After cleaning, several layers of silicon dioxide, silicon nitride, or polycrystalline silicon are grown on a
wafer through a chemical diffusion process. The process is usually accomplished in a vacuum chamber at
elevated temperatures. Several chemicals containing VOC's and HAP's are used in the process. These are
routed to the water treatment plant or to one of several VOC abatement systems. The wafer production
phase ends with an electrical test probe to test for correct function.

Acid and ammonia scrubbers: The used acid or ammonia solution is routed through the scrubber by first
entering a packed chamber and encountering a flue gas stream that is either cross-flow or counter-flow to
the contacting liquid. The contaminated contacting liquid is sprayed over the chamber packing for
efficient mass transfer of the flue gas components. Removal of acid is controlled by maintaining a
minimum pH value of 6.0, having a minimum of 5' of packing media, and a minimum flow rate of 6 gpm
per square foot.

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VOC abatement system: Uses a honeycomb-like wheel (aka rotors) to adsorb and remove VOC's from the
process air streams. The desorption air is heated and passed over the units. This will cause the adsorbed
VOC's to volatize after which it is routed to a thermal oxidizer. The destruction of VOC's is controlled by
maintaining temperature of the thermal oxidizer at 1,250-1,500 degrees Fahrenheit and maintaining a
minimum exhaust flow rate.

Support operations: Natural gas boilers equipped with low NOx burners operate to supply steam for
general heating and humidification. An industrial wastewater treatment plant is used to treat the
wastewater and bring it to acceptable levels for discharge to the public system. Storage and dispensing of
gasoline and diesel fuel takes place in several tanks at the source. Painting and welding to support
construction and equipment maintenance occurs in the shop area. Emergency generators are
maintained at the source for back-up power.

APPLICABLE
REGULATIONS: Approval Order DAQE-AN114080020-23, issued May 31, 2023.

SOURCE INSPECTION
EVALUATION:

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 othe1wise, references cited in these AO conditions refer
to those rules. [R307- l O1]
Status: This is not an inspection item.
I.2 The limits set forth in this AO shall not be exceeded without prior approval. [R307-401]
Status: In compliance. No limit exceedances were found during this inspection.
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]
Status: In compliance. No unapproved modifications were discovered.
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]
Status: In compliance. All requested records have been made available.

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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]
Status: In compliance. The source appeared to be operated and maintained in a manner consistent with good air pollution control practices. Texas Instruments utilizes SAP software for their preventative maintenance program. Maintenance records are kept.
I.6 The owner/operator shall comply with UAC R307-l07. General Requirements: Breakdowns.
[R307-107]
Status: In compliance. The company is aware of the breakdown rule and reports when necessary.
I.7 The owner/operator shall comply with UAC R307-l 50 Series. Emission Inventories.
[R307- l 50]
Status: In compliance. Emission inventories have been submitted as required.
Section II: SPECIAL PROVISIONS
II.A.I Lehi Facility Semiconductor Manufacturing Facility
II.A.2 Emergency Generator
Location: Building 10
Unit ID: 1OEG-01
Capacity: 1850 HP Applicability: Subpart ZZZZ
II.A.3 Emergency Generator Location: Building 11
Unit ID: l IEG-01 Capacity: 896 HP Applicability: Subpart ZZZZ
II.A.4 Emergency Generator
Location: Building 20
Unit ID: 20EG-01 Capacity: 115 HP Applicability: Subpart ZZZZ
II.A.5 (8) Boilers Location: Building 30
Unit ID: 30BLR-01 thru 08
Capacity: 25.1 MMBtu/hr (each) Controls: Low NOx Burners (30 ppm NOx)
30 BLR-01 thru 03, 07 and 08 are equipped with FGR Applicability: Subpart De

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II.A.6 (4) Boilers Location: Building 30
Unit ID: 30BLR-09 thru 12
Capacity: 25.2 MMBtu/hr (each)
Controls: Low NOx Burners (30 ppm NOx for 09 and 10, 9 ppm NOx for 11 and 12)
30 BLR-09 and 10 are equipped with FGR
Applicability: Subpart De I.A.7 (2) Emergency Generator
Location: Building 30 Unit ID: 30EG-01 and 02
Capacity: 1817 HP (each) Applicability: Subpart ZZZZ II.A.8 (4) Cooling Towers Location: Building 30
Unit ID: 30CT-0l and 04 Controls: Drift eliminator (each)
II.A.9 (2) Acid Scrubbers Location: Building 31
Unit ID: 31SCRA-01 and 02 II.A.IO Water Treatment Plant Lime Silo Baghouse
Location: Building 31
Unit ID: 3 lSILO-BH-01
II.A.11 (2) VOC Abatement Units Location: Building 40 Unit ID: 40VOC-01 and 02
Control: Roto concentrators with thermal oxidizer Thermal Oxidizer Capacity: Less than 5 MMBtu/hr (each)
II.A.12 (4) VOC Abatement Units Location: Building 40
Unit ID: 40CSE-01 thru 04
Control: Thermal oxidizer Thermal Oxidizer Capacity: Less than 5 MMBtu/hr (each)
II.A.13 (8) Acid Scrubbers Location: Building 40
Unit ID: 40SCRA-01 thru 08
II.A.14 (5) Ammonia Scrubbers Location: Building 40
Unit ID: 40SCRC-01 thru 05
II.A.15 Emergency Generator
Location: Building 40 Unit ID: 40EG-01
Capacity: 1863 HP
Applicability: Subpart IIII

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II.A.16 Emergency Generator Location: Building 40 Unit ID: 40EG-02 Capacity: 1863 HP Applicability: Subpart ZZZZ
II.A.17 (4) VOC Abatement Units Location: Building 50
Unit ID: 50VOC-01 and 02
Control: Roto concentrators with thermal oxidizer Thermal Oxidizer Capacity: Less than 5 MMBtu/hr
II.A.18 (16) Acid Scrubbers Location: Building 50 Unit ID: 50SCRA-0l thru 16
II.A.19 (6) Ammonia Scrubbers Location: Building 50
Unit ID: 50SCRC-01 thru 06
II.A.20 (3) Emergency Generators
Location: Building 50 Unit
ID: 50EG-01 thru 03 Capacity: 1818 HP (each)
Applicability: Subpart ZZZZ
II.A.21 (2) Acid Scrubbers Location: Building 51
Unit ID: 51SCRA-0l and 02
II.A.22 Emergency Generator
Location: Building 51 Unit ID: 51EG-01 Capacity: 263 HP Applicability: Subpart ZZZZ
II.A.23 (2) Solvent Waste Tanks Location: Building 51
Unit ID: 51SWF-01 and 02 Capacity: 10,000 (each)
II.A.24 (2) Solvent Waste Tanks Location: Building 51
Unit ID: 51SWP-01 and 02 Capacity: 10,000 (each)
II.A.25 (6) Acid Scrubbers Location: Building 60
Unit ID: 60SCRA-05 and 10
II.A.26 Emergency Generator Location: Building 60 Unit ID: 60EG-01 Capacity: 896 HP Applicability: Subpart ZZZZ
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II.A.27 Emergency Generator Location: Building 60 Unit ID: 60EG-01 Capacity: 2206 HP Applicability: Subpart IIII
II.A.28 Emergency Generator Location: Building 61 Unit ID: 61EG-0l Capacity: 755 HP Applicability: Subpart IIII
II.A.29 Cooling Tower Location: Building 61 Unit ID: 61CT-01
Controls: Drift eliminator
II.A.30 (6) VOC Abatement Units (NEW) Location: Building 70 Unit ID: 70VOC-01 thru 06
Control: Roto concentrators with thermal oxidizer Thermal
Oxidizer Capacity: Less than 5 MMBtu/hr (each)
II.A.31 (14) Boilers (NEW) Location: Building 70
Unit ID: 70BLR-0l thru 14 Capacity: 25.2 MMBtu/hr (each) Applicability: Subpart De
II.A.32 (17) Acid Scrubbers (NEW) Location: Building 70
Unit ID: 70SCRA-0l and 17
II.A.33 (11) Ammonia Scrubbers (NEW) Location: Building 70
Unit ID: 70SCRC-01 thru 11
II.A.34 (11) Emergency Generators (NEW)
Location: Building 70 Unit ID: 70EG-01 thru 11 Capacity: 2206 HP (each) Applicability: Subpart IIII
II.A.35 Water Treatment Plant (NEW) Lime Silo Baghouse Location: Building 70 Unit ID: 70SILO-BH-01
II.A.36 (4) Solvent Storage Tanks (NEW) Location: Building 70
Unit ID: 70SWF-01 thru 04 Capacity: 10,000 (each)
II.A.37 (4) Cooling Towers (NEW)
Location: Building 70 Unit ID: 70CT-01 and 04 Controls: Drift eliminator (each)
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II.A.38 Gasoline Storage Tank
Location: Building 99
Unit ID: 99GASTK Capacity: 2000 gal
II.A.39 Diesel Storage Tank
Location: Building 99 Unit ID: 99DSLTK
Capacity: 2000 gal
II.A.40 Emergency Generator
Location: Building 101 Unit ID: l0IEG-01 Capacity: 109 HP Applicability: Subpart ZZZZ
II.A.41 Misc. Natural Gas Combustion Sources
All-natural gas operated equipment with a capacity less than 5 MMBtu/hr.
II.A.42 Fugitive VOC and Chemical Emissions Chemical storage areas
Wastewater treatment
Chemical container rinsing and decontamination
Material warehouse Bulk gas plant
Chillers and refrigeration systems
II.A.43 Misc. Operations
Ground maintenance operations
Vehicle maintenance Road Maintenance
Minor abrasive blasting Minor metal plating
Status: In compliance. No unapproved equipment was observed. A pit is being excavated for the second manufacturing facility.

SECTION II: SPECIAL PROVISIONS
II.B REQUIREMENTS AND LIMITATIONS
II.B.1 Site Wide Requirements II.B.l.a Visible emissions from the following emission points shall not exceed the following values:
A. All baghouses - 10% opacity
B. All packed bed scrubbers - I 0% opacity
C. All boilers - 10% opacity
D. All diesel engines - 20% opacity
E. All other points - 20% opacity
[R307-401-8]
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II.B.l.a.l Opacity observations of emissions from stationary sources shall be conducted according to 40 CFR 60, Appendix A, Method 9. [R307-401-8]
Status: In compliance. No visible emissions were observed coming from any point during this inspection. No fugitive dust was observed. Dirt in the open pit excavation area and haul roads appeared sufficiently wet. II.B.l.b The plant wide emissions of VOCs and HAPs from manufacturing and associated operations shall not exceed:
A. 132.26 tons of VOCs per rolling 12-month period
B. 22.42 tons of hydrogen fluoride per rolling 12-month period
C. 6.36 tons of hydrogen chloride per rolling 12-month period
D. 6.92 tons of chlorine per rolling 12-month period
E. 4.01 tons of Hexane per rolling 12-month period. [R307-401-8]
II.B.1.b.1 Compliance with the limitations shall be determined on a rolling 12-month total. No later than
45 days after the end of each month, a new 12-month total shall be calculated using data from the previous 12 months. [R307-401-8]
II.B.1.b.2 VOC and HAP emissions from the non-combustion sources shall be determined by maintaining a record of VOC- and HAPs- containing materials used each month. The record shall include the following data for each item used:
A. Name of the VOC- and HAPs- emitting material, such as paint,
adhesive, solvent, thinner, reducers, chemical compounds, toxics, isocyanates, etc.
B. Weight and process where the material is used in pounds per gallon
C. Percent by weight of all VOCs and HAPs for each individual material
used. The recommended source of the information is from the
manufacturer's material/chemical Safety Data Sheet (SDS). The
owner/operator shall obtain SDS data from manufacturer and retain information on site
D. The amount of VOCs emitted from controlled manufacturing processes shall
be calculated by the following procedure:
VOC emissions= (VOC Process Chemical Usage) x (Volatility Estimate) x (1-DRE/100)
Where: DRE= Destruction Removal Efficiency of the VOC abatement systems= 98.5%
Volatility Estimate= An estimate of VOC chemical volatility to be verified at least one time
per year by subtracting the amount of VOC-containing materials collected as waste from the
amount of VOC-containing materials used in the manufacturing processes.
E. The amount of HAPs emitted from controlled manufacturing process shall
be calculated by the following procedure:
For aqueous chemicals containing HAPs:
HAP emissions= (HAP Process Chemical Usage) x (Volatility Estimate) x (l-DRE/100)
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Where:
DRE= Destruction Removal Efficiency of the acid scrubber system= 85% for HCl and 95%
for HF
Volatility Estimate= 1.0% for HF and 1.5% for HCl
For gaseous chemicals containing HAPs or HAP precursors:
HAP Emissions= (HAP or HAP Precursor Chemical Usage) x (Amount Consumed in Process) x (Decomp) x (l-DRE/100)
Where:
DRE= Destruction Removal Efficiency of the acid scrubber system= 85% for HCl, 95% for HF
and 50% for Cb
The factors "Amount Consumed in Process" and "Decomp" will be based on available data,
actual measurements, mass balances, knowledge of the process, or engineering judgment.
F. The cumulative total of the 12 previous months VOC and HAPs emissions shall
not exceed the amount specified above.
[R307-401-8]
Status: In compliance. During the 12-month period ending February 28, 2025, emissions were calculated and recorded as: VOCs – 5.64 tons HF – 1.09 tons HCl – 0.35 tons CL2 – 0.09 tons Hexane – 0.47 tons Texas Instruments maintains spreadsheets to track product use and emissions through the manufacturing process, and accounts for portions of product being recycled back into the processes, to waste, to control devices, etc. II.B.1.c TI shall submit a Title V application to obtain an operating permit within 12 months after the unit(s) making the source subject to the Title V permitting program are operational. At the
time the source is subject to the Title V permitting program TI will be subject to 40 CFR 63, Subpart BBBBB (National Emission Standards for Hazardous Air Pollutants for
Semiconductor Manufacturing) and 40 CFR 63, Subpart DDDDD (National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and
Institutional Boilers and Process Heaters). [R307-401-8]
Status: Not applicable. Construction of the second manufacturing facility has not begun. II.B.2 Boiler Requirements II.B.2.a Natural gas used to fuel all the boilers at the Lehi Facility shall not exceed 4,064 MMscf per
rolling 12-month period. [R307-401-8]
II.B.2.a.1 Compliance with the natural gas limit shall be determined on a rolling 12-month basis. No later than 45 days after the end of each month, a new 12-month total shall be calculated using data
from the previous 12 months. Records of fuel combusted shall be kept for all periods when
the plant is in operation. Fuel combusted by the boilers shall be determined from natural gas
flow meters on each boiler. [R307-401-8]
Status: In compliance. Records indicated that 650.5 MMscf was used in boilers during the 12-month period ending December 31, 2024.
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II.B.3 Scrubber Requirements II.B.3.a Packed-bed acid scrubbers shall operate within the following limits:
A. A design exhaust gas flow ranging up to a maximum of 44,000 acfm depending on the name-plate for the scrubber
B. The scrubber liquid pH shall be greater than or equal to six. The pH shall be measured continuously. The scrubber liquid pH shall be recorded daily and
maintained in a daily log.
[R307-401-8]
II.B.3.a.1 The owner/operator shall install, calibrate, maintain, and operate a monitoring device for
continuous measurements. Calibration shall be performed according to the manufacturer's
instructions. [R307-401-8]
Status: In compliance. Packed-bed acid scrubbers are designed for a maximum exhaust gas flow up to 44,000 acfm. Scrubber liquid pH is continuously monitored and is recorded in daily logs. Calibrations/instrument checks are performed according to manufacturer recommendations. Spot checks of instantaneous readings and historic trend lines indicated compliance with pH minimums. II.B.3.b Packed-bed wet ammonia scrubbers shall operate within the following limits:
A. Scrubbers shall have a design exhaust gas flow rate up to a maximum of 20,000
acfm
B. The scrubber liquid pH shall be less than or equal to seven. The pH shall be
measured continuously. The scrubber liquid pH shall be recorded daily and maintained in a daily log.
[R307-401-8]
II.B.3.b.l The owner/operator shall install, calibrate, maintain, and operate a monitoring device for the
continuous measurements. Calibration shall be performed according to the manufacturer's
instructions. [R307-401-8]
Status: In compliance. Packed-bed wet ammonia scrubbers are designed for a maximum exhaust gas flow up to 22,000 acfm. Scrubber liquid pH is continuously monitored and is recorded in daily logs. Calibrations/instrument checks are performed according to manufacturer recommendations. Spot checks of instantaneous readings and historic trend lines indicated compliance with pH maximums. II.B.4 VOC Abatement Units Requirements II.B.4.a.1 The VOC Abatement Systems (including thermal oxidizers with or without rotor concentrators) shall maintain a combustion chamber temperature greater than 1,250 degrees Fahrenheit.
The exhaust gas flow shall not exceed 34,000 acfm depending on the nameplate for the
unit. [R307-401-8]
Status: In compliance. VOC abatement systems are operated with a minimum temperature of 1,250 degrees. Alarm setpoints notify operators if an excursion is being approached. Electronic records are kept. Historic trendlines and instantaneous readings were spot checked during this inspection with no deviations noticed. II.B.4.b The combustion chamber temperature for the VOC abatement systems shall be continuously monitored with equipment located such that an inspector/operator can safely read the output
at any time. The temperature reading shall be accurate to within 1% of full scale.
[R307-401-8]
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II.B.4.b.1 Daily records of readings shall be maintained. The instrument shall be inspected for
functionality, replaced, or calibrated during scheduled maintenance per manufacturer's recommendations. [R307-401-8]
II.B.4.b.2 The sum of voe abatement bypass hours (from the voe abatement systems) shall not exceed 713 hours per rolling 12-month period. [R307-401-8]
Status: In compliance. VOC abatement systems are operated with a minimum temperature of 1,250 degrees. Alarm setpoints notify operators if an excursion is being approached. Electronic records are kept and temperature is logged daily. Historic trendlines and instantaneous readings were spot checked during this inspection with no deviations noticed. Calibrations/instrument checks are performed according to manufacturer recommendations. 124.55 hours of bypass were recorded during the 12-month period ending February 28, 2025. II.B.5 Emergency Generator Requirements II.B.5.a 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. [R307-401-8]
II.B.5.a.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 and time the emergency engine was used
B. The duration of operation in hours
C. The reason for emergency engine usage.
[R307-401-8]
II.B.5.a.2 To determine the duration of operation, the owner/operator shall install a non-resettable hour meter for each emergency engine. [R307-401-8]
Status: In compliance. Generator operation is recorded on a spreadsheet. Generators operate for 1/2 hour per month for preventative maintenance and readiness testing. No generator was operated for more than 100 hours for non-emergency use. II.B.5.b The owner/operator shall only use diesel fuel (e.g. fuel oil #1, #2, or diesel fuel oil additives) as
fuel in each emergency engine. [R307-401-8]
II.B.5.b.1 The owner/operator shall only combust diesel fuel that meets a sulfur content of 15 ppm or less.
[R307-401-8]
II.B.5.b.2 To demonstrate compliance with the 15 ppm requirement, the owner/operator shall maintain
records of diesel fuel purchase invoices or obtain certification of sulfur content from the
diesel fuel supplier. The diesel fuel purchase invoices shall indicate the diesel fuel requirements. [R307-401-8]
Status: In compliance. Fuel trip tickets are kept on record. The most recent fuel oil delivery was #2 USLD from Reladyne.

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II.B.5.c For emergency generator engines located in building 70, only two emergency generator engines
can operate for testing and maintenance at any one time between 8:00 AM and 5:00
PM. [R307-401-8]
Status: Not applicable. This building has not been constructed.
EMISSION INVENTORY: Taken from DAQ’s 2023 emissions inventory database (SLEIS):

Pollutant Emissions (Tons/yr)

PM10 9.31
PM2.5 4.75
SO2 0.374
NOX 17.40
CO 22.05
VOC 6.49
NH3 5.99

PREVIOUS ENFORCEMENT
ACTION: None during the previous five years.

COMPLIANCE STATUS &
RECOMMENDATIONS: Texas Instruments should be found in compliance with the conditions of
the Approval Order evaluated during this inspection.

HPV STATUS: Not applicable

COMPLIANCE
ASSISTANCE: None required.

RECOMMENDATION
FOR NEXT INSPECTION: Inspect as usual

ATTACHMENT: VEO sheet