DAQ-2024-011004

1
DAQC-CI156980001-24
Site ID 15698 (B1)

MEMORANDUM

TO: FILE – METRO READY MIX LLC – Talons Cove Concrete Batch Plant

THROUGH: Chad Gilgen, Minor Source Compliance Section Manager

FROM: Irene Tucker, Environmental Scientist

DATE: September 17, 2024

SUBJECT: FULL COMPLIANCE EVALUATION, Minor, Utah County

INSPECTION DATE: June 20, 2024

SOURCE LOCATION: 4103 East Spring Run Parkway
Eagle Mountain, UT 84005
SOURCE CONTACTS: Rob Carney, Plant Foreman, 702-539-0665,
[e-mail]

Tyler Hodson, Environmental Compliance Coordinator, 385-228-
3653, [e-mail]

Bryan Jorgensen, Environmental Manager, 801-250-0132, 801-
597-4471, [e-mail]

OPERATING STATUS: In operation

PROCESS DESCRIPTION: Metro Ready Mix is a concrete batch plant that combines both
Dry/Transit Mix and Wet/Central Mix capabilities. The dry
transit mix concrete batch plant weighs fine sand and coarse
gravel, Portland cement, and fly ash in a weigh hopper. All of
these ingredients are then routed, via a charging chute, into a
mixer truck. Water and admixtures are discharged through the
same charging chute into the mixer truck. The wet/central mix
plant combines the above ingredients with water and other
admixtures in a concrete mixer that is permanently installed at
the plant. The pre-mixed concrete is then routed, via a charging
chute, into a mixer truck for transportation to jobsite. Dust is
controlled by central collectors with filters that are electronically
monitored.

APPLICABLE REGULATIONS: Approval Order (AO) DAQE-ADAQE-AN156980002-17, dated
May 11, 2017
/ :
2
SOURCE EVALUATION:

Name of Permittee: Permitted Location:

Metro Ready Mix LLC - Talons Cove Concrete
Batch Plant

343 West 400 South 4103 East Spring Run Parkway
Salt Lake City, UT 84101 Eagle Mountain, UT 84005

SIC Code: 3273: (Ready-Mixed Concrete)

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]
Status: In Compliance. There were no modifications to the equipment or processes
approved by this AO. Metro Ready Mix did not exceed any limits set forth in this AO. Metro Ready Mix maintains records for at least two years, and also maintains records of
maintenance activities performed on approved equipment. Metro Ready Mix indicated that there were no breakdowns resulting in an emissions event. Metro Ready Mix is no longer required to submit an Emissions Inventory Report. Their combined PTE of PM10, NOx,
and SO2 is 24.96 tons per year (tpy), which is below the requirements in R307-150-3(3)(c).

Section II: SPECIAL PROVISIONS

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

II.A.1 Talons Cove Concrete Batch plant Concrete Batch Plant
3
II.A.2 Concrete Batch Plant One (1) central mix concrete batch plant with transit mix capability with combined capacity of 200 cubic yards per hour
II.A.3 Concrete Plant Baghouse One (1) baghouse
II.A.4 Associated Silos For cement and supplement Controlled with dust collectors
II.A.5 Associated Bins For sand and aggregate Controlled with dust collectors
II.A.6 Conveyors Miscellaneous conveyors
II.A.7 Water Heater One natural gas-fired water heater rated at 9.0 MMBtu per hour Controlled with low NOx burners
II.A.8 Diesel Storage Tank One (1) diesel fuel storage tank with a capacity of 12,000 gallons
II.A.9 Mobile Equipment Wheeled loaders, haul trucks, and water truck Listed for information purposes In Compliance. There was no new or unapproved equipment observed onsite. There are dust collectors on the silos. See the attachment for additional information.

II.B Requirements and Limitations
II.B.1 All new equipment shall be subject to the following requirements II.B.1.a 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] Status: Not applicable. This facility had been operating as Alta View Concrete for many years. II.B.1.b Unless otherwise specified in this AO, the owner/operator shall not allow visible emissions from any source to exceed 20% opacity on site and 10% opacity at the property boundary. [R307-201-3, R307-309-5] II.B.1.b.1 Unless otherwise specified in this AO, opacity observations of emissions from stationary sources shall be conducted according to 40 CFR 60, Appendix A, Method 9. [R307-309-4] Status: In Compliance. There were no visible emissions observed during this inspection onsite or at the property boundary. The opacity observations were conducted according to 40 CFR 60, Appendix A, Method 9. See the attachment for additional information.

4
II.B.2 The concrete batch plants shall be subject to the following requirements II.B.2.a The concrete batch plants shall not produce more than 290,000 cubic yards of concrete per rolling 12-month period. [R307-401-8] 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 twentieth 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 sales records. The records of production shall be kept on a daily basis. [R307-401-8] Status: In Compliance. The rolling 12-month concrete production of the records reviewed from June 2023 to May 2024, indicated 75,176 cubic yards. Metro Ready Mix determined daily records of concrete production from all periods when the plant was in operation and also from scale house or sales records. See the attachment for additional information. II.B.2.b The owner/operator shall use a baghouse to control emissions from the weigh hopper loading of the concrete batch plants. Displaced air from the hopper shall pass through the baghouse before being vented to the atmosphere. [R307-401-8] Status: In Compliance. A baghouse controls emissions from the weigh hopper during loading of the concrete batch plant. Displaced air from the hopper is routed through the baghouse before being vented to the atmosphere. II.B.2.c The owner/operator shall install a fabric filter device on all material storage silos and bins associated with the concrete batch plant. Displaced air from the silos shall pass through the fabric filter devices before being vented to the atmosphere. [R307-401-8] Status: In Compliance. There is a fabric filter device on all material storage silos and bins associated with the concrete batch plant. Displaced air from the silos is routed through the fabric filter devices before being vented to the atmosphere. II.B.2.d The owner/operator shall not consume more than 19.3 MMscf of natural gas per rolling 12-month period in the hot water heater. [R307-401-8] II.B.2.d.1 To determine compliance with a rolling 12-month total the owner/operator shall calculate a new 12-month total by the twentieth day of each month using data from the previous 12 months. Records of consumption shall be kept for all periods when the plant is in operation. Consumption shall be determined by utility billing statement. The records of consumption shall be kept on a monthly basis. [R307-401-8] Status: In Compliance. The records reviewed of the rolling 12-month natural gas consumption from June 2023 to May 2024, indicated 75,176 cubic yards. Metro Ready Mix determined monthly records of natural gas consumption from all periods when the plant was in operation and also from the utility billing statement. II.B.2.e Visible emissions from the following emission points shall not exceed the following values: A. The concrete batch plant baghouse - 7% opacity B. All material storage silos and bins - 10% opacity C. The conveyor transfer points - 7% opacity D. The conveyor drop points - 20% opacity E. The water heater exhaust - 10% opacity. [R307-312, R307-401-8] Status: In Compliance. There were no visible emissions observed during this inspection from the concrete batch plant baghouse, the material storage silos and bins, the conveyor transfer points, and the conveyor drop points. The opacity observations were conducted according to 40 CFR 60, Appendix A, Method 9. See the attachment for additional information.
5
II.B.3 All loader routes shall be subject to the following requirements II.B.3.a The owner/operator shall use water application to maintain opacity limits listed in this AO. The owner/operator may stop applying water to the loader routes and wheeled-vehicle operational areas when the temperature is below freezing. [R307-401-8] II.B.3.a.1 Records of water application shall be kept for all periods when the plant is in operation. The records shall include the following items: A. Date and time treatments were made B. Number of treatments made and quantity of water applied C. Rainfall amount received, if any D. Records of temperature, if the temperature is below freezing. [R307-401-8] Status: In Compliance. During this inspection, unpaved haul roads and other unpaved operational areas were being watered to control fugitive dust. Metro Ready Mix has a retention pond with recyclable water used to water unpaved haul roads and unpaved operational areas. See the attachment for additional information. Metro Ready Mix maintains records of water and chemical treatment to control fugitive dust. Water treatment records were reviewed from June 2023 through May 2024. Records reviewed also indicated that magnesium chloride treatment was last applied to control fugitive dust in April 2024. II.B.3.b The owner/operator shall not allow visible emissions from loader routes and operation areas on site to exceed 20% opacity on site and 10% opacity at the property boundary. [R307-309-5, R307-401-8] II.B.3.b.1 Visible emission determinations for fugitive dust emissions from loader routes and loader operation 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 1/2 vehicle length behind the vehicle and not less than 1/2 the height of the vehicle. [R307-309-4, R307-401-8] Status: In Compliance. There were no visible emissions observed during this inspection from loader routes and loader operation areas. The operational areas are paved in concrete. The opacity observations were conducted according to 40 CFR 60, Appendix A, Method 9. See the attachment for additional information. II.B.4 All haul road and fugitive dust sources shall be subject to the following requirements II.B.4.a The owner/operator shall cover all haul roads with road-base material and shall use water and chemical suppressant application to maintain opacity limits listed in this AO. The owner/operator may stop applying water and chemical suppressant to the haul roads when the temperature is below freezing. [R307-401-8]

6
II.B.4.a.1 Records of water and chemical suppressant application shall be kept for all periods when the plant is in operation. The records shall include the following items: A. Date and time treatments were made B. Number of treatments made, dilution ratio, and quantity applied C. Rainfall amount received, if any D. Records of temperature, if the temperature is below freezing. [R307-401-8] Status: In Compliance. During this inspection, the unpaved gravel road base haul roads and other unpaved operational areas were being watered to control fugitive dust. Metro Ready Mix has a retention pond with recyclable water used to water unpaved haul roads and unpaved operational areas. See the attachment for additional information. Metro Ready Mix maintains records of water and chemical treatment to control fugitive dust. Water treatment records were reviewed from June 2023 through May 2024. Records reviewed also indicated that magnesium chloride treatment was last applied to control fugitive dust in April 2024. II.B.4.b Mobile equipment speed limitation: The speed of mobile equipment (trucks, front-end loaders, etc.) shall not exceed 15 miles per hour. The speed limit shall be posted, at a minimum, on site at the beginning of the haul road so that it is clearly visible from the haul road. [R307-401-8] II.B.4.c The owner/operator shall not allow visible emissions from haul roads and fugitive dust sources on site to exceed 20% opacity on site and 10% opacity at the property boundary. [R307-309-5, R307-401-8] II.B.4.c.1 Visible emission determinations for fugitive dust emissions from haul-road traffic and mobile equipment in 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 1/2 vehicle length behind the vehicle and not less than 1/2 the height of the vehicle. [R307-309-5, R307-401-8] Status: In Compliance. The posted speed limit for all mobile equipment and haul-road traffic indicated 10 miles per hour. See the attachment for additional information. There were no visible emissions observed during this inspection onsite from haul-road traffic and mobile equipment. The opacity observations were conducted according to 40 CFR 60, Appendix A, Method 9. See the attachment for additional information. II.B.4.d The combined area occupied by all storage piles on site shall not exceed 2.0 acres. [R307-401-8] II.B.4.d.1 To determine compliance with the total acres of the storage piles, the owner/operator shall measure the total area of the storage piles at least once every six months and shall maintain a record of the total acres of the storage piles. To determine the acres of the storage piles on site, the owner/operator shall use a handheld GPS unit and travel around the base of each storage pile on site to calculate the area of each storage pile on site. Records of the total acres of the storage piles shall contain the following: A. Date of measurements B. Size of each storage pile on site C. Total acres of all storage piles combined. [R307-401-8]

7
II.B.4.e The combined disturbed areas on site shall not exceed 10.0 acres. [R307-401-8] II.B.4.e.1 To determine compliance with the total acres of the disturbed areas, the owner/operator shall measure the total disturbed areas at least once every six months and shall maintain a record of the total acres of the disturbed areas. To determine the acres of the disturbed areas on site, the owner/operator shall use a handheld GPS unit and travel around the base of each disturbed area on site to calculate the area of each disturbed area on site. Records of the total acres of the disturbed areas shall contain the following: A. Date of measurements B. Size of each disturbed area on site C. Total acres of all disturbed areas combined. [R307-401-8] Status: In Compliance. According to the GPS results for June 24, 2024, the combined area occupied by all storage piles indicated 0.37 acres, and the combined disturbed areas from the GPS results reviewed indicated 6.21 acres. II.B.4.f The owner/operator shall install water sprays on all unenclosed conveyor drop points on site. The owner/operator shall apply water from conveyor sprays and water trucks to all storage piles on site to control fugitive emissions. Sprays shall operate as required to maintain the opacity limits listed in this AO when the temperature is above freezing. [R307-401-8] II.B.4.g The owner/operator shall comply with all applicable requirements of R307-309 for Fugitive Emission and Fugitive Dust sources on site. [R307-309] II.B.4.h The owner/operator shall comply with an FDCP acceptable to the Director for control of all dust sources associated with the equipment listed in II.A of this AO. The owner/operator shall submit an FDCP to the Director, attention: Compliance Section, for approval within 30 days of the date of this AO. If the owner/operator has an approved FDCP in place, it shall comply with the most current FDCP approved by the Director. [R307-309] Status: In Compliance. Water sprays have been installed on conveyor drop points and recycled water from the retention pond is used on storage piles to control fugitive emissions. The posted haul road speed limit indicated 10 miles per hour. Metro Ready Mix maintains a Fugitive Dust Control Plan dated January 30, 2019. Metro Ready Mix maintains records of water and chemical treatment to control fugitive dust. Water treatment records were reviewed from June 2023 through May 2024. Metro Ready Mix last applied magnesium chloride to control fugitive dust in April 2024.

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.

8
AREA SOURCE RULES EVALUATION:

The following Area Source Rules were evaluated during this inspection:

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

Status: In Compliance. Metro Ready Mix maintains a Fugitive Dust Control Plan dated January 30,
2019. Metro Ready Mix maintains records of water and chemical treatment to control fugitive dust.
Water treatment records were reviewed from June 2023 through May 2024. Metro Ready Mix last
applied magnesium chloride to control fugitive dust in April 2024. Water sprays have been installed
on conveyor drop points, and recycled water from the retention pond is used on storage piles to
control fugitive emissions.
R307-312 - Aggregate Processing Operations for PM2.5 Nonattainment Areas
Status: In Compliance. There were no visible emissions observed during this inspection from the concrete batch plant baghouse, the material storage silos and bins, the conveyor transfer points, and
the conveyor drop points. The opacity observations were conducted according to 40 CFR 60, Appendix A, Method 9. See the attachment for additional information.
EMISSION INVENTORY: Not applicable. Metro Ready Mix is no longer required to submit an Emissions Inventory Report. Their combined PTE of PM10, NOx, and SO2 is 24.96 tpy, which is below the requirements in R307-150-3(3)(c).
Listed below is the estimated total potential emissions (PTE) on AO:
DAQE-ADAQE-AN156980002-17-17, dated May 11, 2017, is provided. PTE are supplied for
supplemental purposes only.

Criteria Pollutant PTE tons/yr Actuals tons/yr
CO2 Equivalent 1163.00
Carbon Monoxide 0.81
Nitrogen Oxides 0.48
Particulate Matter - PM10 24.47
Particulate Matter - PM10 (Fugitives) 22.26
Particulate Matter - PM2.5 3.13
Particulate Matter - PM2.5 (Fugitives) 2.31
Sulfur Dioxide 0.01
Volatile Organic Compounds 0.09
Hazardous Air Pollutant PTE lbs/yr Actuals lbs/yr
Generic HAPs (CAS #GHAPS) 60

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

COMPLIANCE STATUS &
RECOMMENDATIONS: Metro Ready Mix is in compliance with the conditions in
Approval Order (AO) DAQE-AN156980002-17, dated May 11,
2017. Metro Ready Mix maintains good housekeeping practices.

9
HPV STATUS: Not Applicable.

RECOMMENDATION FOR
NEXT INSPECTION: Inspect as usual. Required PPE includes steel-toe booths, hard
hat, safety glasses, and reflective vest.

NSR RECOMMENDATIONS: None at this time.

ATTACHMENTS: Applicable Supporting Documentation Included