DAQ-2024-010968

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DAQC-CI100550001-24
Site ID 10055 (B1)

MEMORANDUM

TO: FILE – KILGORE COMPANIES, LLC – Hyrum Pit

THROUGH: Chad Gilgen, Minor Source Compliance Section Manager

FROM: Daniel Riddle, Environmental Scientist

DATE: October 9, 2024

SUBJECT: FULL COMPLIANCE EVALUATION, Minor, Cache County

INSPECTION DATE: June 12, 2024

SOURCE LOCATION: 410 North 800 East
Hyrum, UT 84319

SOURCE CONTACTS: Bryan Jorgensen, Environmental Director
801-597-4471, [e-mail]

OPERATING STATUS: Operating normally at the time of inspection.

PROCESS DESCRIPTION: Asphalt plant: Aggregate for the hot plant is produced on site by
the crushing plant. Aggregate is taken from the stock piles and
placed in feed-bins by a front-end loader. It is then conveyed
from an appropriate feed bin and screened. It is also at this point
where lime may be added to the aggregate. Next, the conveyor
belt transports the aggregate to the rotary dryer. When needed,
recycled asphalt (RAP) is loaded into the feed bin, conveyed
over a vibrating screen, and fed directly into the lower end of the
drum dryer. Asphalt oil is mixed in and the blend is conveyed to
a storage silo which gravity feeds to transfer trucks. When the
capacity of the silo is reached, the plant is shut down (hot stop).
The facility is only brought back on-line when the level of the
asphalt reaches a low point in the storage silo. The emissions
from the aggregate rotary dryer and drum mixer are fed through
a baghouse before being vented to the atmosphere. A water
truck circulates between this facility and others each day to water
haul roads and operational areas to control fugitive dust.

Aggregate plant: Material is pushed down the face, loaded by
front end loader to the hopper, and drops to a conveyor. The
material then passes through the crusher, screened, and crushed
again, if needed, to produce required size product. Material
processed by this plant is used in the asphalt and batch plants and
also shipped off site as needed.

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Batch plant: Washed sand, washed aggregate, cement powder,
and water are used to produce concrete. The weigh hopper
weighs out sand, aggregate material, and cement powder before
transfer into a concrete mixer truck with water. The mixer truck
mixes the cement while it is being delivered to a local customer.

APPLICABLE REGULATIONS: Approval Order (AO) DAQE-AN100550003-20, dated
September 15, 2020

NSPS (Part 60) OOO: Standards of Performance for Nonmetallic
Mineral Processing Plants,
NSPS (Part 60) I: Standards of Performance for Hot Mix Asphalt
Facilities

SOURCE EVALUATION:

Name of Permittee: Permitted Location:

Kilgore Companies, LLC
Hyrum Pit

7057 West 2100 South 410 North 800 East
Salt Lake City, UT 84128 Hyrum, UT 84319

SIC Code: 1442: (Construction Sand & Gravel)

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]
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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]

Status: In Compliance. No limits set forth in this AO have been exceeded. The source
stated that there have been no modifications to the equipment or processes. The equipment
appeared to be properly operated and maintained according to manufacturer
recommendations. Records are kept as required and were made available after the
inspection. No breakdowns have been reported since the previous inspection. 2023
emissions are reported below.

Section II: SPECIAL PROVISIONS

II.A The approved installations shall consist of the following equipment:

II.A.1 Hyrum Aggregate, Asphalt, & Concrete Plant

II.A.2 Aggregate Plant
Crushing, screening, hauling, conveying, and storing

II.A.3 One (1) Jaw Crusher
Capacity: 400 TPH
NSPS Applicability: Subpart OOO

II.A.4 One (1) Cone Crusher
Capacity: 400 TPH
NSPS Applicability: Subpart OOO

II.A.5 One (1) Vertical Shaft Impactor Crusher
Capacity: 400 TPH
NSPS Applicability: Subpart OOO

II.A.6 Four (4) Triple Deck Screen
Size: 8' x 20'
Capacity: 400 TPH Each
NSPS Applicability: Subpart OOO

II.A.7 One (1) Elevated Screen
Capacity: 400 TPH Each
NSPS Applicability: Subpart OOO

II.A.8 Aggregate Conveyors
NSPS Applicability: Subpart OOO

II.A.9 Miscellaneous Equipment
feeders, stackers, wash screws, wash screens, etc.

II.A.10 Water Heater
Burner Rating: Less than 5 MMBtu/hr
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Fuel: Natural Gas
Listed for information purposes only

II.A.11 Asphalt Plant
Production of Hot Mix Asphalt

II.A.12 One (1) Asphalt Mix Drum
Capacity: 400 TPH
Control: Baghouse
NSPS Applicability: Subpart I

II.A.13 Two (2) Scalping Screen
Size: 6' x 20'
Capacity: 400 TPH
NSPS Applicability: Subpart OOO

II.A.14 One (1) Hot Oil Heater
Rating: < 0.25 MMBtu/hr
Control: Low NOx Burner

II.A.15 One (1) Waste Oil Storage Tank
Maximum Capacity: 15,000 gallons

II.A.16 Two (2) Asphalt Oil Storage Tanks
Maximum Capacity: 30,000 gallons Each
NSPS Applicability: Subpart I

II.A.17 One (1) Lime Silo
Maximum Capacity: 40 Tons
Control: Bin Vent
NSPS Applicability: Subpart I

II.A.18 Three (3) Asphalt Storage Silos
Maximum Capacity: 300 Tons Each
NSPS Applicability: Subpart I

II.A.19 Three (3) Diesel Storage Tanks
Maximum Capacity: 47,000 Gallons Total

II.A.20 One (1) Concrete Batch Plant
Capacity: 220 cubic yards/hour
Control: Baghouse

II.A.21 One (1) Cement Storage Silo
Capacity: 4,000 cf
Control: Bin Vents

II.A.22 One (1) Cement Storage Silo
Capacity: 3,125 cf
Control: Bin Vents

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II.A.23 One (1) Flyash Storage Silo
Capacity: 2,400 cf
Control: Bin Vent

Status: In Compliance. No unapproved equipment was observed at the time of inspection.

• Condition II.A.3 - the jaw crusher is no longer on site
• Condition II.A.18 - only 2 asphalt storage silos are on site
• Condition II.A.21 – this silo is oriented vertically
• Condition II.A.22 – this silo is oriented horizontally
• Two Cat C27 2014 725 kW generators are permitted on site through a
temporary relocation. These were not observed at the time of inspection.
The source stated that they are currently running at this site. See
DAQC-623-24 for more information.

II.B Requirements and Limitations

II.B.1 Site Wide Requirements

II.B.1.a The owner/operator shall only conduct aggregate operations between 6:00 AM and 10:00 PM each day. [R307-401-8]
II.B.1.a.1 Records of aggregate operations shall be kept for all periods when the plant is in operation.
Supervisor monitoring and maintaining of an operations log shall determine hours of operation.
[R307-401-8]

Status: In Compliance. Kilgore Companies, LLC maintains an operations log for
aggregate operations. Reviewing these logs with source contacts demonstrated aggregate
operations only occur between 6 am and 10 pm.

II.B.1.b The owner/operator shall not allow visible emissions from any baghouse, bin vent, dust collector
or fabric filter to exceed 10% opacity. [R307-401-8]

Status: In Compliance. There were no visible emissions observed from any baghouse, bin
vent, dust collector, or fabric filter to exceed 10% opacity during this inspection. See the
attached VEO Form.

II.B.1.c Unless otherwise specified in this AO, the owner/operator shall not allow visible emissions from
any source on site to exceed 20% opacity. [R307-312, R307-401-8]

II.B.1.c.1 Unless otherwise specified in this AO, opacity observations of visible emissions from stationary
sources shall be conducted according to 40 CFR 60, Appendix A, Method 9. [R307-312]

Status: In Compliance. There were no visible emissions observed onsite to exceed 20%
opacity during this inspection. See the attached VEO form.

II.B.2 Aggregate Pit Requirements

II.B.2.a The owner/operator shall not produce more than 1,290,229 tons of processed aggregate material
per rolling 12-month period. [R307-401-8]
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II.B.2.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
of production shall be kept for all periods when the plant is in operation. Production shall be
determined by scale house records or vendor receipts. The records of production shall be kept on
a daily basis. Production shall be determined by supervisor monitoring and maintaining of an
operations log. [R307-401-8]

Status: In Compliance. For the rolling 12-month period from May 2023 – April 2024, a
total of 927,753 tons of aggregate material was processed. See attachments for more
information.

II.B.2.b Visible emissions from the following emission points shall not exceed the following values:

A. Crushers - 12% opacity
B. Screens - 7% opacity
C. All Conveyor Transfer Points - 7% opacity. [R307-312, R307-401-8]

Status: In Compliance. No visible emissions were observed from the crushers, screens, and
all the conveyor transfer points to exceed the AO limits. See the attached VEO form.

II.B.2.c The owner/operator shall install water sprays on all crushers, all screens, all conveyor transfer
points, and all conveyor drop points to control emissions. Sprays shall operate as required to
ensure the opacity limits in this AO are not exceeded. [R307-401-8]

Status: In Compliance. Water sprays are installed as required.

II.B.2.d The owner/operator shall perform monthly periodic inspections to check that water is flowing to
discharge spray nozzles associated with each crusher, screen, and conveyor. If the
owner/operator finds that water is not flowing properly during an inspection of the water spray
nozzles, the owner/operator shall initiate corrective action within 24 hours and complete
corrective action as expediently as practical. [40 CFR 60 Subpart OOO, R307-401-8]

II.B.2.d.1 Records of the water sprays inspections shall be kept and maintained in a logbook for all periods
when the plant is in operation. The records shall include the following items:

A. Date the inspections were made
B. Any corrective actions taken
C. Control mechanism used if sprays are not operating. [40 CFR 60 Subpart OOO,
R307-401-8]

Status: In Compliance. Kilgore Companies, LLC conducts monthly periodic inspections to
ensure that water is flowing to spray nozzles associated with each crusher, screen, and
conveyor as required by this AO Condition. Inspection logs were observed during a
meeting with source contacts on June 18, 2024, and were determined to meet all
requirements of this condition.

II.B.2.e The owner/operator shall conduct an initial performance test for all crushers, screens, and
conveyor transfer points on site within 60 days after achieving maximum production rate but not
later than 180 days after initial startup. Performance tests shall meet the limitations specified in
Table 3 of Subpart OOO. Records of initial performance tests shall be kept and maintained on
site for the lifetime of the equipment. [40 CFR 60 Subpart OOO, R307-401-8]
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II.B.2.e.1 Initial performance tests for fugitive emission limits shall be conducted according to 40 CFR
60.675(c). The owner/operator may use methods and procedures specified in 40 CFR 60.675(e)
as an alternative. [40 CFR 60 Subpart OOO, R307-401-8]

II.B.2.e.2 The owner/operator shall submit written reports of the results of all performance tests conducted
to demonstrate compliance with 40 CFR 60.672 to the Director, attn.: Compliance Section. The
submission shall be postmarked no later than 180 days from the date of this AO or no later than
180 days from equipment start-up, whichever is later. [40 CFR 60 Subpart OOO, R307-401-8]

Status: In Compliance. The Initial Performance tests for all crushers, screens, and
conveyor transfer points were conducted on August 23, 2019, and are included in previous
memos from the DAQ.

II.B.3 All Haul Roads and Fugitive Dust Sources Requirements

II.B.3.a The owner/operator shall not allow visible emissions from haul roads and fugitive dust sources to
exceed 20% opacity on site and 10% at the property boundary. [R307-309-5]
II.B.3.a.1 Visible emission determinations for fugitive dust from haul roads and operational areas shall use procedures similar to Method 9. The normal requirement for observations to be made at 15-second intervals over a six-minute period, however, shall not apply. Visible emissions shall be measured at the densest point of the plume but at a point not less than one-half vehicle length behind the vehicle and not less than one-half the height of the vehicle. [R307-309-5] Status: In Compliance. There were no visible emissions observed from the haul roads and operational areas during this inspection. Watering records were viewed at the time of inspection and again during a meeting with source contacts on June 18, 2024.
II.B.3.b The owner/operator shall comply with a FDCP consistent with R307-309-6. [R307-309-6,
R307-401-8]

Status: In Compliance. Kilgore Companies, LLC maintains a Fugitive Dust Compliance
Plan, and most recently updated it in August of 2022. See DAQC-CI100550001-22 for
more information.

II.B.3.c The owner/operator shall ensure the entry haul road is paved for no less than 0.59 miles in
length. [R307-401-8]

II.B.3.c.1 The paved road length shall be determined through source records or GPS measurements.
[R307-401-8]

Status: In Compliance. The paved portion of the entry haul road is 0.6 miles in length.
This was discussed and proven in images during a meeting with source contacts on
June 18, 2024.
II.B.3.d The owner/ operator shall sweep and apply water to the on-site paved roads as necessary to maintain the listed opacity requirements. [R307-401-8] Status: In Compliance. Kilgore Companies, LLC sweeps and applies water to the on-site paved roads as necessary to maintain the listed opacity requirements as required by this AO. Watering records are maintained in the water truck. Watering records were reviewed during a meeting with source contacts on June 18, 2024. Records were determined to meet all requirements of this condition.
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II.B.3.e The owner/operator shall use a chemical suppressant and water application on unpaved haul
roads to maintain the opacity limits listed in this AO. [R307-401-8]

II.B.3.e.1 Records of treatments shall include:

A. The date, time, and location of applications.
B. The volume of chemical suppressant applied (as applicable).
C. The volume of water applied. [R307-401-8]

II.B.3.e.2 Records of water application shall be kept for all periods when the plant is in operation.
[R307-401-8]

Status: In Compliance. Kilgore Companies, LLC waters unpaved haul roads to comply
with the opacity requirements in this AO. Watering records were reviewed during a
meeting with source contacts on June 18, 2024. Records were determined to meet all
requirements of this condition.

II.B.4 Hot Mix Asphalt Plant Operating Requirements

II.B.4.a The owner/operator shall not produce more than 380,000 tons of hot mix asphalt per rolling
12-month period and 6,000 tons per day. [R307-401-8]

II.B.4.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. To
determine compliance with the daily limitation the owner/operator shall maintain a log of hot
mix asphalt operations. Records of production shall be kept for all periods when the plant is in
operation. Production and daily output shall be determined by the belt scale on the initial feeder,
vendor receipts, or other methods approved by the Director. The records of production and daily
output shall be kept on a daily basis. [R307-401-8]

Status: In Compliance. For the rolling 12-month period from May 2023 – April 2024, a
total of 132,971 tons of hot mix asphalt was produced. The absolute maximum production
during this time period was 2,039 tons. Records were reviewed during a meeting with
source contacts on June 18, 2024. See the attached spreadsheet.

II.B.4.b The owner/operator shall use natural gas, propane, fuel oil, or on-specification used oil as
defined in R315-15, or any combination thereof as fuel in the hot mix asphalt plant.
[R307-401-8]

Status: In Compliance. Kilgore Companies, LLC uses only natural gas in the Asphalt
Plant.

II.B.4.c The sulfur content of any fuel oil burned in the hot mix asphalt plant shall not exceed 15 ppm by
weight. [R307-401-8]

II.B.4.c.1 The sulfur content shall be determined by ASTM Method D2880-71, D4294-89, or approved
equivalent. Certification of fuel oil shall be either by the owner/operator's own testing or by test
reports from the fuel oil marketer. [R307-203-1, R307-401-8]

II.B.4.c.2 The owner/operator shall keep and maintain records of the test certification of sulfur content in
fuel oil. Records of the test certifications shall be kept for all periods when the plant is in
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operation. [R307-203-1, R307-401-8]

Status: In Compliance. A fuel invoice from Parkland, dated February 21, 2020, showing
the purchase of ULSD fuel was observed during a meeting with source contacts on
June 18, 2024.

II.B.4.d The owner/operator shall use a baghouse to control process streams from the asphalt plant drum.
The baghouse shall be sized to handle at least 69,000 ACFM. All exhaust air from the drum shall
be routed through the baghouse before being vented to the atmosphere. [R307-401-8]

Status: In Compliance. A baghouse controls the process stream from the asphalt plant
drum. All exhaust air is routed through the baghouse before venting to the atmosphere.

II.B.4.e The owner/operator shall install a manometer or magnehelic pressure gauge to measure the
differential pressure across the baghouse. The static pressure differential across the baghouse
shall be between 2.0 to 6.0 inches of water column. [R307-401-8]

II.B.4.e.1 The pressure gauge shall be located such that an inspector/operator can safely read the indicator
at any time. The pressure gauge shall measure the pressure drop in 1-inch water column
increments or less. The pressure gauge shall be calibrated according to the manufacturer's
instructions at least once every 12 months. [R307-401-8]

II.B.4.e.2 The owner/operator shall record the reading of the pressure gauge at least once per operating day.
[R307-401-8]

Status: In Compliance. A magnehelic reading recorded on June 12, 2024, showed a
pressure of 2.6 inches of water column. Calibration records and daily checks were
reviewed during a meeting with source contacts on June 18, 2024. See attachments for
checks from June 2024 as well as the location of the gauge.

II.B.4.f The owner/operator shall equip the lime silo with a fabric filter, a baghouse, a bin vent, or a dust
collector to control particulate emissions generated during filling of the silos. [R307-401-8]

Status: In Compliance. According to Kilgore Companies, LLC, the lime silo is equipped
with a baghouse at the top of the silo to control particulate emissions generated during
filling of the silos, as required. See the attached email correspondence.

II.B.4.g PM10 and PM2.5 emissions from the asphalt plant baghouse shall not exceed:

Pollutant: lb/hr Grains/dscf
(68 F, 29.92 in Hg)
Pit Run Material:

PM10 6.17 0.024
PM2.5 6.17 0.024
TSP 7.71 0.030

Recycled Pit Run Asphalt Pavement Mix:

PM10 7.20 0.028
PM2.5 7.20 0.028
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TSP 9.00 0.035.
[40 CFR 60 Subpart I, R307-312, R307-401-8]

II.B.4.g.1 Stack testing to show compliance with the emission limitations stated in the above condition
shall be performed as specified below:

Emission Point: Drum Mixer exhaust passing through the baghouse

Pollutant Testing Status Test Frequency

TSP * #

PM10 and PM2.5 ** @

* Initial compliance testing was conducted.

** Initial test is not required unless specified by the Director.

# Initial test is required. Subsequent tests shall only be performed for PM10 and PM2.5.

@ Test every five years or sooner if required by the Director. Tests may be required if the
source is suspected to be in violation with other conditions of this AO. [R307-165, R307-401-8]

Status: In Compliance. The most recent stack test prior to the date of inspection was
conducted on August 23, 2019. Results were 0.0018 gr/dscf and 0.2298 lb/hr for PM10 and
PM2.5. See the Stack Testing review in DAQC-1644-19 for more information. New stack
testing was conducted on July 9, 2024. A final result is still being processed by the DAQ.
See the attached email correspondence.

II.B.4.g.2 A. Notification:

At least 30 days prior to conducting any emission testing required under any part of UAC, R307,
the owner or operator shall notify the Director of the date, time and place of such testing and
shall submit a source test protocol to the Director. The source test protocol shall outline the
proposed test methodologies, stack to be tested, and procedures to be used. If directed by the
Director, the owner/operator shall attend a pretest conference. The pretest conference shall
include representation from the owner/operator, the tester, and the Director.

B. Reporting:

Upon completion of the DAQ accepted testing methods, the owner/operator shall submit a copy
of the results from each performance test as conducted to the Director within 60 days after the
test has been completed.

C. Sample Location:

The emission point shall be designed to conform to the requirements of 40 CFR 60, Appendix A,
Method 1, or other methods as approved by the Director. An Occupational Safety and Health
Administration (OSHA) or Mine Safety and Health Administration (MSHA) approved access
shall be provided to the test location.

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D. Volumetric Flow Rate:
40 CFR 60, Appendix A, Method 2 or other EPA approved testing method, as acceptable to the
Director.

E. TSP

TSP emissions shall be determined by 40 CFR 60, Appendix A, Method 5 or other EPA
approved testing method, as acceptable to the Director

F. PM10

The following methods shall be used to measure filterable particulate emissions: 40 CFR 51,
Appendix M, Method 201 or Method 201A, or other EPA-approved testing method, as
acceptable to the Director. If other approved testing methods are used which cannot measure the
PM10 fraction of the filterable particulate emissions, all of the filterable particulate emissions
shall be considered PM10.

G. PM2.5

Filterable PM2.5 emissions shall be determined by 40 CFR 51, Appendix M, Method 201A, or
other EPA approved testing method, as acceptable to the Director.

The following methods shall be used to measure condensable particulate emissions: 40 CFR 51,
Appendix M, Method 202, or other EPA-approved testing method, as acceptable to the Director.

The condensable particulate emissions shall not be used for compliance demonstration, but shall
be used for inventory purposes.

H. Calculations

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

I. Test Conditions

All tests shall be conducted in accordance with R307-165-4. [R307-165, R307-401-8]

II.B.4.g.3 New Source Operation

For a new source/emission point, the production rate during all compliance testing shall be no
less than 90% of the maximum production rate (rated capacity) of the plant. If the maximum AO
allowable production rate has not been achieved at the time of the test, the following procedure
shall be followed:

A. Testing shall be at no less than 90% of the production rate achieved to date.

B. If the test is passed, the new maximum allowable production rate shall be 110% of the
tested achieved rate. This new maximum allowable production rate shall be less than
90% of the allowed maximum production rate. This new allowable maximum
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production rate shall remain in effect until successfully tested at a higher rate.
C. The owner/operator shall request a higher production rate when necessary. Testing at no
less than 90% of the higher rate shall be conducted. A new maximum production rate
(110% of the new rate) will then be allowed if the test is successful. This process may
be repeated until the maximum AO production rate is achieved.

Existing Source Operation

For an existing source/emission point, the production rate during all compliance testing
shall be no less than 90% of the maximum production achieved in the previous three (3)
years. [R307-401-8]

Status: In Compliance. See the Stack Testing review in DAQC-1644-19 for more
information on the stack test from August 23, 2019. New stack testing was conducted on
July 9, 2024. A final result is still being processed by the DAQ. See the attached email
correspondence.

II.B.4.h The owner/operator shall comply with the limitations and compliance requirements under
R307-312-5 for burning a fuel other than natural gas or liquefied petroleum gas (LPG).
[R307-312]

Status: Not Applicable. Kilgore Companies, LLC uses only natural gas in the asphalt
plant.

II.B.5 Concrete Batch Plant

II.B.5.a The owner/operator shall not produce more than 168,986 cubic yards per rolling 12-month
period. [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
of production shall be kept for all periods when the plant is in operation. Production shall be
determined by production records, vendor or sales receipts, or other methods approved by the
Director. The records of production shall be kept on a monthly basis. [R307-401-8]

Status: In Compliance. For the rolling 12-month period from May 2023 – April 2024,
82,015 cubic yards of concrete were produced. See the attached spreadsheet.
II.B.5.b The owner/operator shall not allow visible emissions from the concrete batch plant to exceed 7% opacity. [R307-312] Status: In Compliance. There were no visible emissions observed during this inspection. See the attached VEO Form.
II.B.5.c The owner/ operator shall control emissions from on-site storage silos with bin vents.
[R307-401-8]

Status: In Compliance. The vertical storage silos are equipped with bin vents as required.

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Section III: APPLICABLE FEDERAL REQUIREMENTS

In addition to the requirements of this AO, all applicable provisions of the following federal programs
have been found to apply to this installation. This AO in no way releases the owner or operator from any
liability for compliance with all other applicable federal, state, and local regulations including
UAC R307.

NSPS (Part 60) OOO: Standards of Performance for Nonmetallic Mineral Processing Plants

Status: In Compliance. Initial performance tests for all crushers, screens, and conveyor transfer points
were conducted on August 23, 2019. Monthly inspections of spray nozzles are conducted and recorded.
Nozzle spray inspection records were reviewed during a meeting with source contacts on June 18, 2024.

NSPS (Part 60) I: Standards of Performance for Hot Mix Asphalt Facilities

Status: In Compliance. The most recent stack test prior to the date of inspection was conducted on
August 23, 2019. See the Stack Testing review in DAQC-1644-19. New stack testing was conducted on
July 9, 2024.

AREA SOURCE RULES EVALUATION:

The following Area Source Rules were evaluated during this inspection:

Emission Standards: Sulfur Content of Fuels [R307-203]

Status: In Compliance. A fuel invoice from Parkland, dated February 21, 2020, showing the
purchase of ULSD fuel was observed during a meeting with source contacts on June 18, 2024.

Emission Standards: Fugitive Emissions and Fugitive Dust [R307-205]

Status: In Compliance. There were no visible fugitive dust emissions observed at the time of
inspection. The source takes steps to minimize fugitive dust by watering roads. See the attached
VEO form.

Stationary Sources [R307-210]

Status: In Compliance. Compliance with this area source rule is satisfied by compliance with Federal
Requirements NSPS (Part 60) Subparts OOO and I. See Section III above for more information.

Solvent Cleaning [R307-304]

Status: In Compliance. Kilgore Companies, LLC does solvent cleaning that uses Safety-Kleen
Premium Solvent for the cleaning of tools, equipment, and machinery. The solvent has a VOC
content of 6.4-6.7 lb/gal with a VOC composite vapor pressure of 0.5 mmHG at 20 degrees Celsius.
See attachments for email correspondence and SDS.

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Nonattainment and Maintenance Areas for PM10: Emissions and Fugitive Emissions and Fugitive Dust
[R307-309]

Status: In Compliance. No fugitive dust emissions were observed at the time of inspection. See the
attached VEO form.

EMISSION INVENTORY:

Listed before are the Actual Emissions Inventory provided from Kilgore Companies, LLC – Hyrum Pit
for the 2023 emissions year. A comparison of the estimated total potential emissions (PTE) on AO:
DAQE-AN100550003-20, dated September 15, 2020, is provided. PTE are supplied for supplemental
purposes only.

Criteria Pollutant PTE tons/yr Actuals tons/yr
CO2 Equivalent 59817.00 N/A
Carbon Monoxide 26.35 9.40604
Nitrogen Oxides 10.66 2.561
Particulate Matter - PM10 28.63 26.39303
Particulate Matter - PM2.5 13.18 9.99323
Sulfur Dioxide 11.02 0.22517
Volatile Organic Compounds 9.37 3.28503

Hazardous Air Pollutant PTE lbs/yr Actuals lbs/yr
Acetaldehyde (CAS #75070) 500 N/A
Formaldehyde (CAS #50000) 1220 420
Generic HAPs (CAS #GHAPS) 740 N/A
Hexane (CAS #110543) 360 N/A
Naphthalene (CAS #91203) 260 N/A
Toluene (CAS #108883) 1120 N/A

PREVIOUS ENFORCEMENT
ACTIONS: No enforcement actions within the past five years.

COMPLIANCE STATUS &
RECOMMENDATIONS: In regards to Approval Order (AO) DAQE-AN100550003-20,
dated September 15, 2020: In Compliance with the conditions in
AO DAQE-AN100550003-20, dated September 15, 2020. The
facility appears to be well-maintained and operated.

HPV STATUS: Not Applicable.

RECOMMENDATION FOR
NEXT INSPECTION: Inspect at typical interval. Request to view as many records as
possible on site with Kilgore's SharePoint software. Request
other records over email. Make sure to check the magnehelic
15
reading on the baghouse and ask to see the solvent cleaning
system.

NSR RECOMMENDATIONS: Add Safety-Kleen solvent cleaner to equipment list.

ATTACHMENTS: VEO form, email correspondence, rolling 12-month totals,
magnehelic checks, gauge picture, SDS, DAQ email.
Daniel Riddle <[e-mail]>
10055 - follow up to air quality inspection
12 messages
Daniel Riddle <[e-mail]>Wed, Jun 12, 2024 at 2:36 PM
To: Bryan Jorgensen <[e-mail]>, [e-mail]
Bryan,
Today I met with Bob and Justin at Kilgore Companies' plant in Hyrum, Utah. Things looked pretry good - here are the
records I require to complete my inspection report:
From AO 100550003-20:
Condition II.B.1.a.1 - record demonstrating no aggregate operations occur before 6 am or after 10 pm
Condition II.B.2.a - production of aggregate (May 2023 - April 2024)
Condition II.B.2.d.1 - record of monthly nozzle spray inspections
Condition II.B.3.b - copy of most recent FDCP
Condition II.B.3.c - record demonstrating the haul road is paved for at least 0.59 miles
Condition II.B.3.e.1 - records of seeping, watering, or using chemical suppressant on paved haul roads
Condition II.B.4.a - total production of hot mix asphalt (May 2023 - April 2024) as well as demonstrating that tonnage
never exceeds 6000 in a single day
Condition II.B.4.c - ULSD invoice or proof of purchase
Condition II.B.4.e.1 - record of annual calibration of magnehelic pressure gauge
Condition II.B.4.e.2 - record of daily check of pressure gauge
Condition II.b.4.a - production of concrete (May 2023 - April 2024)
Please provide these records by June 19, 2024 and let me know if you have any questions.
Thanks,
Daniel
Bryan Jorgensen <[e-mail]>Wed, Jun 12, 2024 at 2:47 PM
To: Daniel Riddle <[e-mail]>, "[e-mail]" <[e-mail]>
Hey Daniel,

Would you be able to have a Teams call or version of? I can show you this on our environmental system we
have and where our folks should be able to show you the information while you are onsite? I’m available
tomorrow after 11:00 if that works for you.

Thanks,

Bryan Jorgensen
Environmental Director – West Region
M [phone]
O [phone]
E [e-mail]

9/25/24, 10:19 AM State of Utah Mail - 10055 - follow up to air quality inspection
https://mail.google.com/mail/u/0/?ik=3e54b7a6bd&view=pt&search=all&permthid=thread-a:r274736092921752833&simpl=msg-a:r-710144338013684…1/5
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Daniel Riddle <[e-mail]>Wed, Jun 12, 2024 at 3:11 PM
To: Bryan Jorgensen <[e-mail]>
Cc: [e-mail]
I could do tomorrow at 3 pm - if not let's do Tuesday at 11?
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Bryan Jorgensen <[e-mail]>Wed, Jun 12, 2024 at 3:13 PM
To: Daniel Riddle <[e-mail]>
Cc: "[e-mail]" <[e-mail]>
Tomorrow at 3:00 works for me. I can send you a TEAMS invite, or if you use another system them send me
one.
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Daniel Riddle <[e-mail]>Wed, Jun 12, 2024 at 11:44 PM
To: Bryan Jorgensen <[e-mail]>
Teams work for me
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Bryan Jorgensen <[e-mail]>Thu, Jun 13, 2024 at 2:35 PM
To: Daniel Riddle <[e-mail]>
Hey Daniel,

I apologize, but I’ve had something come up that is taking me a different direction today. Could we
reschedule for next Tuesday at 11:00 as you had proposed as an alternative?
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9/25/24, 10:19 AM State of Utah Mail - 10055 - follow up to air quality inspection
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From: Daniel Riddle <[e-mail]>
Sent: Wednesday, June 12, 2024 2:37 PM
To: Bryan Jorgensen <[e-mail]>; [e-mail]
Subject: 10055 - follow up to air quality inspecon
[Quoted text hidden]
Daniel Riddle <[e-mail]>Thu, Jun 13, 2024 at 2:58 PM
To: Bryan Jorgensen <[e-mail]>
Sure - sounds good to me.
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Daniel Riddle <[e-mail]>Thu, Aug 29, 2024 at 11:13 AM
To: Bryan Jorgensen <[e-mail]>, Tyler Hodson <[e-mail]>
Bryan and Tyler,
I had used our meeting on June 18, 2024 where I viewed your records in my initial memo for this site. My manager
reviewed my submission, but he still wants physical records for some conditions. Here are the physical copies he has
requested to include in my memo:
From AO 100550003-20:
Condition II.B.2.A - rollin 12 showing numbers for each individual month - you can send it in a similar format that
you used for site 10031 (attached below)
Condition II.B.4.a - rolling 12 showing each individual month and a few days showing that production doesn't
exceed 6000 tons in any individual day
Condition II.B.4.e - could you send me a reading of the magnehelic gauge from June 12, 2024? Or else a number
from your most recent check on the gauge, and a picture of where it is located.
Condition II.B.5.a - rolling 12 for concrete showing individual months
As a reminder, the 12-month interval we were using for this site was May 2023 - April 2024.
A question regarding Condition II.B.4.f - is the lime silo equipped with a fabric filter, a baghouse, a bin vent or a
dust silo? This condition says it can be equipped with any of these, and I don't recall observing which it was at the
time of my inspection.
A previous inspection memo noted a parts washer on site for vehicle and equipment products. What chemical is
being used with the parts washer? Is any solvent cleaning being conducted separate from the parts washer (with
rags, brushes, etc?) The rules I'm determining compliance for are R307-304 and R307-335. It's possible that only
one of these rules applies to this facility, but I'm attaching both rules if you want to review them.
Finally, regarding DAQC-623-24, issued June 27, 2024 (after the date of my inspection on June 12, 2024) - could
you let me know about the status of these two generators? Are they on site and being used now?
Thank you - if possible, please respond with these records by September 6, 2024. Let me know if you have any
questions.
Daniel
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DAQ-2024-008642.pdf
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Tyler Hodson <[e-mail]>Tue, Sep 10, 2024 at 5:11 PM
To: Daniel Riddle <[e-mail]>, Bryan Jorgensen <[e-mail]>
Daniel,

Thank you for your patience in getting these records sent over. I am attaching a couple documents to show
compliance with the regulations referenced in your email:
The first document contains:
Page 1 is for Conditions II.B.2.A, II.B.4.a, II.B.5.a
Page 2 is the mag gauge readings from June
Page 3 is a picture of the magnehelic gauge from where it sits on the control panel
The second document is the SDS sheet for Safety-Kleen Solvent
Please see section 9 for the VOC content. The SDS shows that the content of VOCs is 6.4-6.7
lb/gal or 770-800 g/l, which falls under the Tools, equipment and machinery category in R307-
304-5(1). According to the SDS, the solvent also qualifies under section (2) of R307-304-5 as it
has a VOC composite vapor pressure of 0.5 mmHg at room temperature.
In reference to the other items mentioned in your email:
The Lime Silo has a filtration system at the top of the silo.
The two C27 generators from DAQC-623-24 are currently up and running at the site.

Please let us know if you have any other questions.

Thank you,

Tyler Hodson
Administrative Environmental Manager
[phone]
[e-mail]
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From: Daniel Riddle <[e-mail]>
9/25/24, 10:19 AM State of Utah Mail - 10055 - follow up to air quality inspection
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Daniel Riddle <[e-mail]>Thu, Sep 12, 2024 at 2:46 PM
To: Tyler Hodson <[e-mail]>
Cc: Bryan Jorgensen <[e-mail]>
Thanks for sending this information. I'll let you know if I need anything else.
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Tyler Hodson <[e-mail]>Wed, Sep 25, 2024 at 10:06 AM
To: Daniel Riddle <[e-mail]>
Cc: Bryan Jorgensen <[e-mail]>
Daniel,

I got your voicemail yesterday and was able to speak with the hot plant manager out at Hyrum this morning
to confirm the information about the filtration system on the lime silo, To be more specific about the filtration
system on the lime silo, it is a baghouse. While this is not our plant, here is an example of a similar setup
lime silo with a baghouse on top:

The red box is a baghouse filtration system, which is what our lime silo at Hyrum also uses.
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Daniel Riddle <[e-mail]>Wed, Sep 25, 2024 at 10:19 AM
To: Tyler Hodson <[e-mail]>
Cc: Bryan Jorgensen <[e-mail]>
Thank you for the clarification.
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9/25/24, 10:19 AM State of Utah Mail - 10055 - follow up to air quality inspection
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Apr-24 93,022 927,753 8,328 82,015 2,403 132,971 6 401
Mar-24 58,537 834,731 4,450 73,687 0 130,568 0 N/A
Feb-24 32,241 776,194 1,706 69,237 0 130,568 0 N/A
Jan-24 21,213 743,953 2,538 67,531 0 130,568 0 N/A
Dec-23 67,355 722,740 4,733 64,993 1,319 130,568 1 1,319
Nov-23 102,985 655,385 8,437 60,260 20,914 129,249 15 1,394
Oct-23 94,757 552,400 10,306 51,824 21,854 108,335 14 1,561
Sep-23 113,184 457,643 9,120 41,518 30,581 86,481 15 2,039
Aug-23 93,247 344,459 9,508 32,398 17,721 55,900 21 844
Jul-23 72,204 251,212 7,190 22,890 13,702 38,179 14 979
Jun-23 103,203 179,008 9,171 15,700 15,067 24,477 17 886
May-23 75,805 75,805 6,529 6,529 9,410 9,410 16 588
Yes Yes Yes Yes
168,986 R12
Tons 380,000
Month
Production
HMA Plant
Natural Gas
(Tons)
In Compliance?
AO
Production
Limits
R12
Tons 1,290,229 R12
Cubic Yards
HMA Days of
Operation
HMA Tons
per day
Daily
Tons 6,000
Kilgore Companies, LLC DBA
Kilgore Contracting
Hyrum Agg Pit
Hyrum RMX Batch Plant
Hyrum HMA Plant
410 North 800 East
Hyrum, UT 84319
FDCP# - 17643
AO# DAQE-AN100550001-19
Rolling 12
HMA Plant
Natural Gas
(Tons)
Month /
Year
Monthly
Production
Aggs / Pit
(Tons)
Rolling 12
Aggs / Pit
(Tons)
Monthly
Production
RMX Plant
(Cubic Yards)
Rolling 12
RMX Plant
(Cubic Yards)
168,986
9,4109,410
15,06715,067
13,70213,702
17,72117,721
86,481
130,568
129,249
108,335
Enter Your Name Here Enter the date of Mag Gauge
Reading Record Daily Mag Gauge Reading
Justin Harris 6/27/2024 2.1
Justin Harris 6/25/2024 1.9
Justin Harris 6/24/2024 2
Justin Harris 6/20/2024 2
Justin Harris 6/18/2024 2.4
Justin Harris 6/13/2024 2.6
Justin Harris 6/12/2024 2.6
Justin Harris 6/11/2024 2.6
Justin Harris 6/9/2024 2.2
Justin Harris 6/7/2024 2.7
Justin Harris 6/5/2024 2.2
Justin Harris 6/4/2024 2.4
June
6/13/20246/13/2024
6/18/2024
1.91.9