DAQ-2025-002137

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

Department of
Environmental Quality

Tim Davis
Executive Director

DIVISION OF AIR QUALITY
Bryce C. Bird
Director

Air Quality Board
Kim Frost, Chair
Michelle Bujdoso, Vice-Chair
Tim Davis
Seth Lyman
Colton Norman
Sonja Norton
John Rasband
Jeff Silvestrini
Dave Spence
Bryce C. Bird,
Executive Secretary

SPENCER J. COX
Governor

DEIDRE HENDERSON
Lieutenant Governor
DAQ-033-25

UTAH AIR QUALITY BOARD MEETING
TENTATIVE AGENDA

Wednesday, May 7, 2025 - 1:30 p.m.
195 North 1950 West, Room 1015
Salt Lake City, Utah 84116

Board members may be participating electronically. Interested persons can participate telephonically by
dialing 1-475-299-8810 using access code: 449-801-632#, or via the Internet at meeting link:
meet.google.com/dpm-oqgm-nzk

I. Call-to-Order

II. Date of the Next Air Quality Board Meeting: June 4, 2025

III. Approval of the Minutes for February 5, 2025, Board Meeting.

IV. Propose for Final Adoption: Amendment to Section R307-110-17. Section IX, Control Measures
for Area and Point Sources, Part H, Emission Limits; and Amendments to Utah State
Implementation Plan, Section IX.H.11 and Section IX.H.12: Emission Limitations and Operating
Practices. Presented by Ana Williams.

V. Five-Year Review: R307-122. General Requirements: Heavy Duty Vehicle Tax Credit.
Presented by Jazmine Lopez.

VI. Propose for Public Comment: Amend R307-230. NOx Emission Limits for Natural Gas-Fired
Water Heaters. Presented by Glade Sowards.

VII. Informational Items.
A. Grants and Incentives Update. Presented by Lisa Burr.
B. Air Toxics. Presented by Leonard Wright.
C. Compliance. Presented by Harold Burge, Rik Ombach, and Chad Gilgen.
D. Monitoring. Presented by Sally Lloyd.
E. Other Items to be Brought Before the Board.
F. Board Meeting Follow-up Items.

In compliance with the Americans with Disabilities Act, individuals with special needs (including auxiliary communicative aids
and services) should contact LeAnn Johnson, Office of Human Resources at [phone], TDD [phone] or by email
at [e-mail].
ITEM 4

195 North 1950 West • Salt Lake City, Utah Mailing Address: P.O. Box 144820 • Salt Lake City, Utah 84114-4820 Telephone [phone] • Fax [phone] • T.D.D. 800 346-3128 www.deq.utah.gov Printed on 100% recycled paper
State of Utah

Department of
Environmental Quality

Tim Davis Executive Director
DIVISION OF AIR QUALITY Bryce C. Bird Director
SPENCER J. COX Governor DEIDRE HENDERSON Lieutenant Governor
DAQ-040-25
M E M O R A N D U M TO: Air Quality Board
THROUGH: Bryce C. Bird, Executive Secretary THROUGH: Jazmine Lopez, Rules Coordinator FROM: Ana Williams, Environmental Scientist DATE: April 24, 2025 SUBJECT: PROPOSE FOR FINAL ADOPTION: Amendment to Section R307-110-17. Section IX, Control Measures for Area and Point Sources, Part H, Emission Limits; and Amendments
to Utah State Implementation Plan, Section IX.H.11 and Section IX.H.12: Emission Limitations and Operating Practices. ______________________________________________________________________________________
On November 6, 2020, the Environmental Protection Agency (EPA) proposed “Approval and Promulgation of Implementation Plans; State of Utah; Salt Lake City and Provo, Utah PM2.5
Redesignations to Attainment and Utah State Implementation Plan Revisions.” (85 FR 71023). This proposal included approval of Utah’s moderate and serious State Implementation Plans (SIPs) for the 2006 24-hr PM2.5 standard for the Salt Lake City nonattainment area (SLC NAA) and the Provo NAA. EPA
received adverse public comments regarding how best available control technology (BACT) was addressed for the four major point source refineries included in the SLC NAA. Over the past four years, the division has worked closely with EPA and the refineries to address the comments, resulting in these “Part H” SIP amendments. The proposed amendments to Part H that are incorporated in the SIP through Section R307-110-17 result in the change of specific emission limitations for five major industrial sources located within the serious PM2.5 NAAs, as well as a clarification in the Recordkeeping and Reporting General Requirements for all major industrial sources located within the serious PM2.5 NAAs. These emission limitations serve to fulfill Utah’s statutory obligations under Section 189(b) of the Clean Air Act (CAA).
The emission limitations proposed in this rulemaking will replace the existing source-wide PM2.5, nitrogen oxides (NOx), and sulfur dioxide (SO2) limitations originally adopted by the Air Quality Board on January 2, 2019, for four major industrial sources: Big West Oil LLC Refinery, Chevron Products Company –
DAQ-040-25 Page 2

Salt Lake Refinery, HF Sinclair Woods Cross Refinery, and Tesoro Refining and Marketing Company LLC Marathon Refinery: Salt Lake City Refinery. The existing source-wide PM2.5, NOx, and SO2 limitations are being removed at the direction of the EPA as they determined that the limitations did not meet the definition of BACT. Emissions at the sources will continue to be controlled and meet BACT requirements through the existing “Petroleum Refineries” requirements found in Section IX.H.11. General Requirements in conjunction with the new NOx emission limitations that have been added to Section IX.H.12. Source-Specific Emission Limitations for each of the listed refineries. Details regarding the additional analysis that identified the proposed emission limitations and supporting information surrounding these proposed changes can be found in the documentation associated with the proposed revisions. Amendments were also made to Hexcel’s Part H requirements and there is an additional memo
in this package that includes details. On February 5, 2025, the Utah Air Quality Board approved the proposed amendments for a 30-day public
comment period. This public comment period began on March 1, 2025, and ended on March 31, 2025. During this time, the division received written comments from four commenters.
The division has reviewed and evaluated all comments received during this 30-day public comment period in accordance with the Utah Administrative Rulemaking Act, Utah Code § 63G-3-301(11)(b). All written comments received by the division have been posted on its webpage where they can be viewed in their entirety. A summary of comments received, and the division’s responses can be found in Appendix A. The comments received came from impacted stakeholders, and included:
● Requested changes to proposed limits and deadlines;
● Requested changes to stack testing frequency;
● Requested additional language added for flexibility;
● Requested clarifying language added to Part H and the background SIP documentation; and
● Requested language changes to the timing of stack testing. After review and consideration of comments, the following changes were made to the proposed
amendments:
● Additional clarifying language and minor editorial changes were added to Part H and the
background SIP documentation.
● The emission limits for the FCC Heater H-101 and Reformer Heaters H-621, 622, 624 Combined Stack at Big West Oil were increased from 0.1 lb/MMBtu and 0.05 lb/MMBtu, respectively, to 0.16 lb/MMBtu and 0.08 lb/MMBtu, respectively.
● The deadlines for the installation of stack testing ports and initial stack testing for the FCC Furnaces at Chevron were changed from December 31, 2025, to December 31, 2027.
● The stack testing frequency for two units at Marathon was changed from annually to every three years.
● The option for compliance with a Continuous Emissions Monitoring System (CEMs) instead of stack testing was added for each refinery.
● A numbering error by the division was corrected in Section IX.H.11, where proposed Conditions
IX.H.11.i and j were correctly moved to become Conditions IX.H.11.g.viii and ix. During the final stages of state rulemaking, EPA will propose rulemaking at the federal level, review
public comments, and finalize. This entire process must be complete by the end of the calendar year in 2025 to align with the projected modeling years included in the maintenance plan attainment demonstration and meet consent decree deadlines. The division and EPA have worked closely together during this process
with the intention of meeting deadlines.
DAQ-040-25 Page 3

Recommendation: Staff recommend the Board approve the amendments to Section R307-110-17; and amendments to Utah State Implementation Plan, Section IX.H.11 and Section IX.H.12: Emission Limitations and Operating Practices, for final adoption.
Page 1 of 4
APPENDIX A
Amendment to Section R307-110-17 Salt Lake City Nonattainment Area 2006 NAAQs PM2.5 SIP Responses to Public Comment
On February 5, 2025, the Utah Air Quality Board proposed the incorporation of amendments to the Salt Lake City Nonattainment Area (SLC NAA) Serious PM2.5 State Implementation Plan (SIP) by reference into R307-110-17 for a 30-day public comment period. This public comment period began on March 1, 2025, and ended on March 31, 2025. During this time, staff at the Utah Division of Air Quality (UDAQ, the Division) continued ongoing conversations with stakeholders, and received submissions of written comments from four commenters.
The Division has reviewed and evaluated all comments received during this 30-day public comment period in accordance with the Utah Administrative Rulemaking Act, Utah Code § 63G-3- 301(11)(b). All written comments received by the Division have been posted on its webpage where they can be viewed in their entirety. Below is a summation of comments and UDAQ responses: Comments received from Big West Oil LLC Refinery (BWO): 1) BWO Comment 1: “UDAQ proposed NOx limits for FCC Heater H-101 and the Reformer Heaters H-621, H-622, and H-624 based upon AP-42 emission factors for small boilers. UDAQ chose this basis due to site-specific data not being available for these process heaters. In March 2025, BWO conducted NOx performance testing on these units as required under proposed Part H.12.b.iii and to verify whether compliance with the proposed NOx limits under proposed Part H.12.b.i is achievable. This performance test report was submitted to Robert Sirrine on 3/26/2025 and is available upon request. The performance testing results indicate that the proposed NOx limits are not achievable. BWO proposed alternate limits for these heaters based on the performance test results: 0.16 lb/MMBtu for the FCC Heater H-101 and 0.08 lb/MMBtu for the
Reformer Heater H-621/622/624 (Combined Stack).” UDAQ Response: After reviewing the submitted information included with this public comment
and the “Review of stack test report received March 26, 2025” (Document ID DAQC-347-25) approved by Robert Sirrine (Environmental Scientist in the Major Source Compliance Section) through Harold Burge (Major Source Compliance Section Manager) on April 7, 2025, the
Division agrees with BWO that the proposed NOx limits need to be changed from 0.1 lb/MMBtu and 0.05 lb/MMBtu for the FCC Heater H-101 and Reformer Heaters H-621, 622, 624 Combined Stack, respectively, to 0.16 lb/MMBtu and 0.08 lb/MMBtu for the FCC Heater H-101 and Reformer Heaters H-621, 622, 624 Combined Stack, respectively. These limits are still in-line with the limits on similar emission units located across the refineries. The Division has revised the relevant portions of the SIP and Part H to reflect this change. Comments received from Chevron Products Company Salt Lake Refinery (Chevron):
2) Chevron Comment 1: “The Fluid Catalytic Cracking Unit (FCC) furnaces (F-32021 FCC Furnace #1 and F-32023 FCC Furnace #2) are not currently configured with stack testing ports. Due to unforeseen circumstances at the Refinery, the installation of the stack testing ports on those furnaces can no longer be safely completed during 2025. We request to adjust the initial compliance stack testing deadline to allow additional time to safely install the stack testing ports.”

Page 2 of 4
UDAQ Response: The Division has taken this comment into consideration and revised the relevant portions of the SIP and Part H to reflect this change.
3) Chevron Comment 2: “The proposed language regarding the timing of stack testing for the boilers and furnaces currently requires that ‘stack testing shall be performed at least once every three (3) years from the date of the last stack testing’. Requiring the timing of the stack testing to be based on the previous stack testing date will cause the testing dates to shift forward within the calendar year every time to ensure compliance. To maintain the Refinery in a safe posture while meeting required production rates for stack testing requires the predictability of the testing to be at the same time every year. This also provides greater flexibility during instances where periods of maintenance or process shutdowns would otherwise require moving planned testing forward. Additionally, there are several regulations that allow flexibility for the timing of stack testing…Based on the language in these regulations, we request that Subsection IX.H.12.d be
revised.” UDAQ Response: The Division appreciates Chevron providing additional information regarding
stack testing language in state and federal regulations, and the suggested wordings for changing this language. After additional review, the Division will be keeping the original proposed wording regarding stack testing timing. This language is in line with the Division’s current
standard language for stack testing both in existing permits and in the PM2.5 SIP and is similar to the previous stack testing language that had been included in the replaced PM2.5 SIP Source-wide Caps. To provide additional clarification on the timing, the Division has revised the wording in the relevant portions of Part H. Comments received from Tesoro Refining & Marketing Company LLC Marathon Refinery (Marathon): 4) Marathon Comment 1: “The following statement was deleted from the proposed amendment: ‘Stack testing is not required for natural gas/refinery fuel gas combustion equipment with a NOx CEMs.’ This statement provides clarity if a CEMs is added later as the method for demonstrating compliance versus stack testing. This language should be added to the end of the text…Tesoro also recommends that it be added to the IX.H.11.e as a new subsection ‘K’.” UDAQ Response: The Division appreciates this suggestion. After additional review of the suggested language and the replaced language originally included in PM2.5 SIP Source-wide Caps, the Division has taken this comment into consideration and revised the relevant portions of
the SIP and Part H to reflect this change. While the Division appreciates the suggestion to change this in the General Language of Section IX.H.11.e, changes to this section are beyond the scope of this SIP amendment.
5) Marathon Comment 2: “In this proposed amendment the testing for Tesoro is required annually from the date of the last stack test. This annual frequency is more stringent than the testing frequency of every three years listed in Tesoro’s PM10 SIP, the original PM2.5 SIP, and the Ozone SIP. Furthermore, the other three refineries (Big West, Chevron, and Holly Frontier Sinclair) amended PM2.5 SIP sections maintained the three year testing frequency. Tesoro is put at a competitive disadvantage with the addition of the more stringent testing frequency. Tesoro requests the testing frequency be changed back to every three years.” UDAQ Response: The stack testing frequency for Marathon was taken from the most recent Approval Order. After additional review of the last four years of stack testing data for these two
units, which have consistently been below the proposed limits, the Division agrees that the stack
Page 3 of 4
testing frequency for Marathon is more stringent than necessary and can be reduced to every three years. The Division has taken this comment into consideration and revised the relevant portions
of the SIP and Part H to reflect this change. 6) Marathon Comment 3: “Tesoro recommends adding additional text to this section for clarity.” UDAQ Response: The Division has made this change to the relevant portion of Part H. 7) Marathon Comment 4: “Tesoro requests the API separator listed in the table be renamed ‘Existing API Separator’. Tesoro is currently constructing a new API separator that will have a fixed roof vented to a control device. UDAQ Response: The Division has made this change to the relevant portion of Part H.
8) Marathon Comment 5: “UDAQ has not been consistent in establishing testing frequency required by dates in the PM10 SIP, PM2.5 SIP, nor Ozone SIP. For example, the following
sources in the PM2.5 SIP only require testing ‘every X years’: ATK, Compass, KUC, LHoist, Nucor, P&G. Other sources are required to test ‘every X years from the date of the last test’. Requiring a source to test X number of years exactly from the date of the last test requires a
source to substantially shorten the timeframe between each test in order to ensure completion of the test by a specific date. In order to maintain consistency across all regulated entities in the PM2.5 SIP and treat all sources the same UDAQ should establish a uniform definition of a required by test ‘date’…UDAQ should remove all references of ‘from the date of the last test’ for all sources in this proposed PM2.5 SIP and update section IX.H.11.e…with a uniform definition…and adding a provision…that would allow a source to request up to two 30-day extensions to complete the test event.” UDAQ Response: The Division appreciates the suggestions for consistency in stack testing frequency, as well as the suggested wording and recommendations for the stack testing frequency for specific sources and in Section IX.H.11 General Conditions. See UDAQ Response to Chevron
Comment 2 for an additional explanation regarding this language. While the Division appreciates the suggestion to change the General Language of Section IX.H.11.e, changes to this section are beyond the scope of this SIP amendment. Comments received from Utah Petroleum Association (UPA):
UPA comments 1, 2, 5, 6, and 7 were supportive comments in support of the proposed SIP Amendment and provided clarifying information relevant to the proposed SIP Amendment. The Division appreciates these comments, and no response was necessary for these comments. 9) UPA Comment 3: “UPA requests that a watermark be placed on each page of the petroleum refinery data supplied and included in appendices to UDAQ’s updated BACT determinations, to explain the context. Although this statement has been provided on the cover page of applicable appendices, UPA does not consider this to be adequate because cover pages may not be read, if read they may be forgotten, and they can easily be separated from the pages of data.” UDAQ Response: The Division appreciates this suggestion and has made this change to the
relevant portions of the SIP documentation.
Page 4 of 4
10) UPA Comment 4: “UPA requests that all subsequent stack tests after the initial test retain the original wording for the due dates, i.e., once every X number of years thereafter…This timing
gave petroleum refineries some measure of flexibility…UPA also requests that the SIP allow petroleum refineries to consider adding a Continuous Emissions Monitoring System (‘CEMS’) in the future, as a future alternative to stack testing.” UDAQ Response: The Division appreciates the additional information on flexibility regarding stack testing timing, as well as the suggested stack testing language. The original wording UPA references both in past SIPs and in the replaced PM2.5 SIP Source-wide Caps for the refineries, where specified, used the wording the Division has proposed. See UDAQ Response to Chevron Comment 2 for an additional explanation regarding this language. Regarding allowing CEMs as an alternative to stack testing, the Division appreciates this
suggestion. After additional review, the Division has taken this comment into consideration and revised the relevant portions of the SIP and Part H to reflect this change.
State of Utah
Administrative Rule Analysis
Revised May 2024

NOTICE OF SUBSTANTIVE CHANGE
TYPE OF FILING: CPR (Change in Proposed Rule)
Rule or Section Number: R307-110-17 Filing ID: Office Use Only
Date of Previous Publication (Only for CPRs): 03/01/2025

Agency Information
1. Title catchline: Environmental Quality, Air Quality
Building: Multi-Agency State Office Building
Street address: 195 N 1950 W
City, state: Salt Lake City, UT
Mailing address: PO Box 144820
City, state and zip: Salt Lake City, UT 84114-4820
Contact persons:
Name: Phone: Email:
Ana Williams 801-536-4153 [e-mail]
Jazmine Lopez 801-536-4050 [e-mail]

Please address questions regarding information on this notice to the persons listed above.

General Information
2. Rule or section catchline:
R307-110-17. Section IX, Control Measures for Area and Point Sources, Part H, Emission Limits.

3. Purpose of the new rule or reason for the change:
The purpose of the amendment to Section R307-110-17 is to amend the Utah State Implementation Plan, Subsections IX.H.11
and IX.H.12 Emission Limits and Operating Practices to comply with the Clean Air Act requirements for Serious PM2.5
nonattainment areas as listed in Title 40 Code of Federal Regulations, Part 51, Subpart Z (40 CFR 51 Subpart Z). Section
R307-110-17 incorporates amendments to Subsections IX.H.11 and IX.H.12 into the rule and shall be amended to change the
Board adoption date to the anticipated adoption date of the amended plan.

4. Summary of the new rule or change:
This rule change is in response to comments received from impacted stakeholders during the public comment process after the
Utah Air Quality Board proposed the amendments for a 30-day public comment period.

The following changes were made in response to public comments:
1) Emission limits for two units at Big West Oil have been increased.
2) The deadline for initial stack testing for two units at Chevron has been changed from 2025 to 2027.
3) The stack testing frequency for two units at Marathon has been changed from annually to every three years.
4) Additional clarifying language has been added to various conditions in Part H.

Fiscal Information
5. Provide an estimate and written explanation of the aggregate anticipated cost or savings to:
A) State budget:
This rule amendment is not expected to create additional costs or savings for the state government. These facilities are already
permitted and inspected under existing rules and have existing stack testing requirements in place. Inspectors will be able to
confirm compliance as part of normal stack testing processes.

B) Local governments:
This rule amendment is not expected to impact local governments; therefore, no costs or savings are anticipated.

C) Small businesses ("small business" means a business employing 1-49 persons):
This rule amendment is not expected to impact small businesses; therefore, no costs or savings are anticipated.

D) Non-small businesses ("non-small business" means a business employing 50 or more persons):
The Utah Division of Air Quality anticipates that these changes to the proposed rule will impact four non-small businesses. The
impacts are described below.

These changes will require new stack testing requirements on 11 emission units located across four non-small businesses.
Stack testing costs were calculated based on information submitted to the UDAQ as part of the BACT/BACM process in 2017 for
the PM2.5 Serious SIP. Assuming an average of $5,441 for stack testing costs, and accounting for inflation changes from 2017
to 2025, an average stack testing value of $7,071.38 was used. Stack tests will be required every three years, and start at
different times across the four non-small businesses.

Therefore, for 11 units, stack testing every three years across four non-small businesses, the estimated impact will be
$77,785.18 per testing period.

E) Persons other than small businesses, non-small businesses, state, or local government entities ("person" means any
individual, partnership, corporation, association, governmental entity, or public or private organization of any character other
than an agency):
This amendment does not apply to persons other than small businesses, non-small businesses, state, or local government
entities; therefore, no additional costs are expected because of these changes.

F) Compliance costs for affected persons (How much will it cost an impacted entity to adhere to this rule or its changes?):
Compliance costs will consist of additional stack testing for four non-small businesses. The impacts are described below.

Compliance costs are estimated at $77,785.18 every testing period for additional stack testing requirements.

G) Regulatory Impact Summary Table (This table only includes fiscal impacts that could be measured. If there are
inestimable fiscal impacts, they will not be included in this table. Inestimable impacts will be included in narratives above.)
Regulatory Impact Table
Fiscal Cost FY2025 FY2026 FY2027
State Government $0 $0 $0
Local Governments $0 $0 $0
Small Businesses $0 $0 $0
Non-Small Businesses $49,499.66 $0 $28,285.52
Other Persons $0 $0 $0
Total Fiscal Cost $49,499.66 $0 $28,285.52
Fiscal Benefits FY2025 FY2026 FY2027
State Government $0 $0 $0
Local Governments $0 $0 $0
Small Businesses $0 $0 $0
Non-Small Businesses $0 $0 $0
Other Persons $0 $0 $0
Total Fiscal Benefits $0 $0 $0
Net Fiscal Benefits $0 $0 $0
H) Department head comments on fiscal impact and approval of regulatory impact analysis:
The Executive Director of the Department of Environmental Quality, Tim Davis, has reviewed and approved this
regulatory impact analysis.

Citation Information
6. Provide citations to the statutory authority for the rule. If there is also a federal requirement for the rule, provide a
citation to that requirement:
Section 19-2-104

Incorporations by Reference Information
7. Incorporations by Reference (if this rule incorporates more than two items by reference, please include additional tables):
A) This rule adds or updates the following title of materials incorporated by references (a copy of materials incorporated
by reference must be submitted to the Office of Administrative Rules; if none, leave blank):
Official Title of Materials Incorporated
(from title page)
Section IX, Control Measures for Area and Point Sources, Part H, Emission Limits.
Publisher Division of Air Quality, Utah Department of Environmental Quality
Issue Date 05/07/2025

Public Notice Information
8. The public may submit written or oral comments to the agency identified in box 1. (The public may also request a
hearing by submitting a written request to the agency. See Section 63G-3-302 and Rule R15-1 for more information.)
A) Comments will be accepted until: 03/31/2025
B) A public hearing (optional) will be held:
Date (mm/dd/yyyy): Time (hh:mm AM/PM): Place (physical address or URL):
N/A
To the agency: If more than one hearing will take place, continue to add rows.

9. This rule change MAY become effective on: 06/30/2025
NOTE: The date above is the date the agency anticipates making the rule or its changes effective. It is NOT the effective date.

Agency Authorization Information
To the agency: Information requested on this form is required by Sections 63G-3-301, 63G-3-302, 63G-3-303, and 63G-3-402.
Incomplete forms will be returned to the agency for completion, possibly delaying publication in the Utah State Bulletin and
delaying the first possible effective date.
Agency head or
designee and title:
Bryce C. Bird, Director, Division of Air
Quality
Date: 04/21/2025

R307. Environmental Quality, Air Quality. 1
R307-110. General Requirements: State Implementation Plan. 2
R307-110-17. Section IX, Control Measures for Area and Point Sources, Part H, Emission Limits. 3
The Utah State Implementation Plan, Section IX, Control Measures for Area and Point Sources, 4
Part H, Emission Limits and Operating Practices, as most recently amended by the Utah Air Quality 5
Board on [February 5, 2025] May 7, 2025, pursuant to Section 19-2-104, is incorporated by reference and 6
made a part of Rule R307-110. 7
8
KEY: air pollution, PM10, PM2.5, ozone 9
Date of Last Change: 2025[February 5, 2025] 10
Notice of Continuation: December 1, 2021 11
Authorizing, and Implemented or Interpreted Law: 19-2-104 12
Page 1 of 1

M E M O R A N D U M

To: File: 11386 – Hexcel Corporation

Through: Jon L. Black, Major New Source Review Section Manager

From: Tad Anderson, Engineer, Major New Source Review Section

Date: January 2, 2025

Subject: PM2.5 SIP Condition Amendment Request

On June 11, 2024, Hexcel Corporation (Hexcel) met with UDAQ to discuss the feasibility of two of the
PM2.5 SIP conditions. The two conditions Hexcel is requesting a feasibility determination on pertain to
Ultra Low NOx Burners (condition H.12.f.iv) and De-NOx Water systems (condition H.12.f.v). Hexcel
submitted two letters on August 1, 2024 addressing the technical feasibility of Ultra Low NOx Burners
with flue gas recirculation on fiber lines 3, 4, and 7 and De-NOx Water Direct Fired Thermal Oxidizer on
fiber lines 13, 14, 15 and 16. UDAQ requested additional information for the technical feasibility.
Hexcel submitted the “SIP Conditions Amendment Request Additional Information” on December 5,
2024. This response addressed both conditions and included an updated BACM analysis. Each SIP
requested removal condition will be addressed individually below.

Condition H.12.f.iv
“Ultra Low NOx Burners with flue gas recirculation shall be installed on Fiber Lines 3, 4 and 7 to
control NOx emissions no later than December 31, 2024.”

Hexcel has submitted a “SIP Condition Amendment Request” on August 1, 2024 and additional
information submitted “SIP conditions Amendment Request Additional Information” on December 6,
2024, which contained a request to remove Condition H.12.f.iv (Ultra Low NOx Burners on fiber lines 3,
4 and 7) due to technical infeasibility.

The submitted documents describe the operational requirements for the thermal oxidizers on fiber lines 3,
4 and 7. The thermal oxidizers are used as a control device for hydrogen cyanide, ammonia and VOCs.
For the thermal oxidizer to operate correctly for the combustion of the hydrogen cyanide, the temperature
must be maintained at approximately 1,400 degrees Fahrenheit. With the addition of the flue gas
recirculation on the low NOx burners to lower the NOx emissions to 9 ppm, the flue gas recirculation
reduces the combustion temperatures (to approximately 1000 degrees Fahrenheit) to lower thermal NOx
creation. For this reason, flue gas recirculation is not technically feasible to be added to a thermal
oxidizer.

The burner size for the existing thermal oxidizers for fiber lines 3 (0.75 MMBtu/hr), 4 (2.0 MMBtu/hr)
and 7 (0.30 MMBtu/hr) are all below 5 MMBtu/hr. Hexcel hired an internationally reputed industrial
pollution control company to determine if the existing burners can be replaced with Ultra Low NOx
burners. The company contacted Honeywell, Fives and Access (burner manufacturers) to determine if
there were any burners that could operate at 1400 degrees Fahrenheit with a low NOx emissions rate. All
three burner companies had no burners at the existing size that could meet the 9 ppm and 1400 degrees
Fahrenheit.

DAQE-MN102370025-18
Page 2

The submitted “SIP conditions Amendment Request Additional Information” on December 6, 2024,
contained an updated BACM. The BACM included a top-down analysis of all the control technologies
for lowering NOx emissions. The BACM demonstrated that Low NOx burner and Ultra Low NOx burner
operation on the thermal oxidizer is technically infeasible. The replacement of the existing burner with a
direct fired thermal oxidizer is technically feasible. The lowest cost to replace the thermal oxidizer with a
direct fired thermal oxidizer is $94,398 per ton removed for fiber line #7 making the replacement
economically infeasible.

Condition H.12.f.v
“De-NOx Water Direct Fired Thermal Oxidizer (DFTO) shall be installed on Fiber Lines 13, 14, 15, and
16 to control NOx emissions no later than December 31, 2024.”

Hexcel has submitted a “SIP Condition Amendment Request” on August 1, 2024 and additional
information submitted “SIP conditions Amendment Request Additional Information” on December 6,
2024, which contained a request to remove Condition H.12.f.v (De-NOx Water Direct Fired Thermal
Oxidizer on fiber lines 13 thru 16) due to technical infeasibility.

The submitted documents described the operational implications from installing the De-NOx water
system to the DFTO. Hexcel has installed the De-NOx water system on Fiber Lines 13, 14, 15 and 16 to
meet the SIP requirements. Once installed and operating, Hexcel experienced the following operational
complications. Hexcel noticed “caking” in the baghouse located downstream of the system. The caking
of the baghouse decreases the removal efficiency and increases maintenance operations which increases
down time. Hexcel experienced an increase in natural gas usage on Fiber Lines 13, 14, 15 and 16, since
the De-NOx water system decreases the burner temperature. The increase in natural gas increases the
combustion emissions of all the associated fiber lines which leads to the formation of more NOx. In
March 2024, Hexcel stack tested the fiber lines and the testing indicated that the De-water system lowered
the destruction removal efficiency of hydrogen cyanide and ammonia. Hexcel hired an internationally
reputed industrial pollution control company to provide a technical analysis of why the De-NOx water
system was not working as designed. The industrial pollution control company concluded that, due to the
DFTO requiring a multi-stage combustion chamber configuration and the system not operating in a zero-
oxygen environment, the De-NOx water system is unable to achieve the designed NOx reductions. The
industrial pollution control company also concluded that the existing system would require extensive
retrofitting to the DFTO. For this reason, the implementation of the De-NOx water system to the DFTO
is not technically feasible.

The use of ultra-low NOx burners with flue gas recirculation and the installation of the De-NOx water
system were not included in the original conclusion for Hexcel’s PM2.5 SIP Evaluation Report and were
not considered as “PM2.5 SIP Specific Requirements” (Section 5 of the UTAH PM2.5 SIP SERIOUS
Evaluation Report dated July 1, 2018). Hexcel submitted a revised BACT analysis on June 19, 2018,
after the June Board meeting. The June 19th submittal revised the economic analysis, which resulted in
the costs of some of the equipment being considered economically feasible. UDAQ had originally
determined the equipment was not economically feasible based on the original economic analysis
received prior to the June meeting. Therefore, based on the revised information, UDAQ had incorporated
new requirements into the final draft as a consideration for ultra-low NOx burners and De-NOx water
system. The PM2.5 SIP modeling analysis had already been completed at this time and there was no need
to revisit the model as this was an assumed reduction in potential emissions which would not affect the
model. Therefore, the removal of the ultra-low NOx burners and De-NOx water system will not result in
an emission increase as these potential reductions in emissions were never considered in the original
modeling analysis performed for the PM2.5 Serious SIP demonstration.
DAQE-MN102370025-18
Page 3

Conclusion
The UDAQ has reviewed the submitted documentation and agrees that the Ultra-Low NOx burner
operation on the thermal oxidizer is technically infeasible, the replacement of the existing burner with a
direct fired thermal oxidizer is technically feasible and the cost to replace the thermal oxidizers with a
direct fired thermal oxidizer is economically infeasible.

The UDAQ will remove PM2.5 SIP conditions IX.H.12.f.iv and IX.H.12.f.v, amend the Utah PM2.5 SIP
Serious Evaluation Report for Hexcel Corporation to incorporate the cost analysis for replacing the
thermal oxidizers with direct fired thermal oxidizers, and update the technological feasibility analysis for
the implementation of a De-NOx water system to the DFTO.

ITEM 5

195 North 1950 West • Salt Lake City, Utah Mailing Address: P.O. Box 144820 • Salt Lake City, Utah 84114-4820 Telephone [phone] • Fax [phone] • T.D.D. 800 346-3128 www.deq.utah.gov Printed on 100% recycled paper
State of Utah

Department of
Environmental Quality

Tim Davis Executive Director
DIVISION OF AIR QUALITY Bryce C. Bird Director
SPENCER J. COX Governor DEIDRE HENDERSON Lieutenant Governor
DAQ-037-25
M E M O R A N D U M TO: Air Quality Board THROUGH: Bryce C. Bird, Executive Secretary FROM: Jazmine Lopez, Rules Coordinator DATE: April 18, 2025 SUBJECT: FIVE-YEAR REVIEW: R307-122. General Requirements: Heavy Duty Vehicle Tax Credit. ______________________________________________________________________________________
Utah Code Title 63G-3-305 requires each agency to review and justify each of its rules within five years of a rule’s original effective date or within five years of the filing of the last five-year review. This review
process is not a time to revise or amend the rules, but only to verify that the rule is still necessary and allowed under state and federal statute. As part of this process, we are required to identify any comments received during and since the last five-year review of each rule. This process is not the time to revisit those
comments or to respond to them. There have not been any comments received on R307-122. DAQ has completed the five-year review for rule R307-122, General Requirements: Heavy Duty Vehicle Tax Credit. The result of the five-year review is found in the attached Five-Year Notice of Review and Statement of Continuation form. Recommendation: Staff recommends the Board continue R307-122, General Requirements: Heavy Duty Vehicle Tax Credit, by approving the attached Five-Year Notice of Review and Statement of Continuation form to be filed with the Office of Administrative Rules.
State of Utah
Administrative Rule Analysis
Revised May 2024
NOTICE OF FIVE-YEAR REVIEW AND STATEMENT OF CONTINUATION
Rule Number: R307-122 Filing ID: Office Use Only
Effective Date: Office Use Only
Agency Information
1. Title catchline:Environmental Quality, Air Quality
Building: Multi Agency State Office Building
Street address: 195 N 1950 W
City, state Salt Lake City, UT
Mailing address: PO BOX 144820
City, state and zip: Salt Lake City, UT 84114-4820
Contact persons:
Name: Phone: Email:
Mat Carlile 385-306-6535 [e-mail]
Jazmine Lopez 801-536-4050 [e-mail]
Please address questions regarding information on this notice to the persons listed above.
General Information
2. Rule catchline:
R307-122. General Requirements: Heavy Duty Vehicle Tax Credit.
3. A concise explanation of the particular statutory provisions under which the rule is enacted and how these
provisions authorize or require this rule:
R307-122 is enacted under the authority granted by Utah Code Sections 59-7-618.1 and 59-10-1033.1, which establish the
income tax credits available for the purchase of qualified heavy-duty vehicles. Subsections 59-7-618.1(6)(a) and 59-10-
1033.1(6)(a) specifically require the purchaser to provide proof of a qualified purchase to the director to claim the tax credit.
Utah Code Section 19-2-104 grants the Air Quality Board the authority to make rules under Title 63G, Chapter 3, Utah
Administrative Rulemaking Act. This statutory authority empowers the Board to establish procedures through R307-122 to
ensure compliance with the requirements for claiming the income tax credit.
These statutory provisions collectively authorize the creation and continuation of R307-122 to define the necessary procedures
for demonstrating eligibility for the tax credit, ensuring that the process remains transparent, consistent, and aligned with
legislative intent.
4. A summary of written comments received during and since the last five-year review of this rule from interested
persons supporting or opposing this rule:
No written comments have been received since the previous review in August 2020.
5. A reasoned justification for continuation of this rule, including reasons why the agency disagrees with comments in
opposition to this rule, if any:
R307-122 remains essential to ensure proper administration of the income tax credits established under Utah Code Sections 59-
7-618.1 and 59-10-1033.1 for the purchase of qualified heavy-duty vehicles. The rule provides a clear framework for verifying
proof of qualified purchases, ensuring compliance with statutory requirements, and preventing misuse of tax credits.
By defining procedures for documentation and verification, R307-122 maintains accountability, promotes administrative
efficiency, and protects public funds. Continuation of the rule is necessary to uphold the integrity of the tax credit program and
fulfill the Air Quality Board’s statutory responsibility under Utah Code Section 19-2-104.
Agency Authorization Information
To the agency: Information requested on this form is required by Section 63G-3-305. Incomplete forms will be returned to the
agency for completion, possibly delaying publication in the Utah State Bulletin.
Agency head or
designee and title:
Bryce C. Bird, Director, Division of Air
Quality
Date: 04/08/2025
Reminder: Text changes cannot be made with this type of rule filing. To change any text, please file an amendment or a
nonsubstantive change.
R307. Environmental Quality, Air Quality. 1
R307-122. General Requirements: Heavy Duty Vehicle Tax Credit. 2
R307-122-1. Authorization and Purpose. 3
(1) This rule is authorized by Sections 59-7-618.1 and 59-10-1033.1. These statutes4
establish criteria and definitions used to determine eligibility for an income tax credit. 5
(2) Rule R307-122 establishes procedures to provide proof of a qualified purchase, in6
accordance with Subsections 59-7-618.1(6)(a) or 59-10-1033.1(6)(a), to the director for a qualified 7
heavy duty vehicle for which an income tax credit is allowed under Sections 59-7-618 or 59-10-8
1033. 9
10
R307-122-2. Definitions. 11
The following additional definitions apply to Rule R307-122. 12
"Heavy duty vehicle" means heavy duty vehicle as defined in Subsection 59-7-618.1(1)(c) 13
and 59-10-1033.1(1)(c). 14
"Original equipment manufacturer (OEM) vehicle" means original equipment 15
manufacturer (OEM) as defined in Subsection 19-1-402(8). 16
"Qualified heavy duty vehicle" means qualified heavy duty vehicle as defined in 17
Subsections 59-7-618.1(1)(e) and 59-10-1033.1(1)(e). 18
"Qualified purchase" means qualified purchase as defined in Subsections 59-7-618.1(1)(f) 19
and 59-10-1033.1(1)(f). 20
"Qualified taxpayer" means qualified taxpayer as defined in Subsections 59-7-618.1(1)(g) 21
and 59-10-1033.1(1)(g). 22
23
R307-122-3. Reservation of a Qualified Heavy Duty Vehicle Tax Credit. 24
(1) A qualified taxpayer shall reserve a qualified heavy-duty vehicle tax credit before25
submitting proof of qualified purchase to obtain approval from the division for the heavy duty 26
vehicle tax credit. A qualified taxpayer shall apply to reserve the tax credit on forms provided by 27
the division, which will include the following: 28
(a) the name of the qualified taxpayer and the qualified taxpayers registered name with the29
United States Department of Transportation (USDOT), 30
(b) the last four digits of the qualified taxpayer's social security number (SSN) or employer31
identification number (EIN), 32
(c) the qualified taxpayer's address, and33
(d) the qualified taxpayer's USDOT number.34
(2) The tax credit shall be reserved for the qualified taxpayer for up to 180 calendar days35
from the division's approval of the request to reserve the credit. 36
(3) If the qualified taxpayer does not meet all of the requirements of Rule R307-122-437
before 181 calendar days after the division's approval of the request to reserve the tax credit, the 38
tax credit will no longer be reserved for the qualified taxpayer. 39
40
R307-122-4. Proof of Qualified Purchase for a Qualified Heavy Duty Vehicle. 41
To demonstrate that a heavy duty vehicle is eligible for the tax credit, proof of qualified 42
purchase shall be made in accordance with Subsections 59-7-605(6)(a) or 59-10-1009(6)(a), by 43
submitting the following documents to the director: 44
(1)(a) a copy of the motor vehicle's window sticker, which includes its Vehicle 45
Identification Number (VIN), or equivalent manufacturer's documentation showing that the heavy 46
duty vehicle: 47
(i) is an OEM natural gas vehicle;48
(ii) has a 100% electric drivetrain; or49
Page 1 of 2
(iii) has a hydrogen-electric drivetrain; or 1
(b) a signed statement by either an Automotive Service Excellence (ASE)-certified 2
technician or Canadian Standards Association (CSA) America CNG Fuel System Inspector that 3
includes the VIN, the technician's ASE or CSA America certification number, and states that the 4
heavy duty vehicle: 5
(i) is an OEM natural gas vehicle; 6
(ii) has a 100% electric drivetrain; or 7
(iii) has a hydrogen-electric drivetrain; 8
(2) an original or copy of the purchase order, customer invoice, or receipt that includes the 9
name of the qualified taxpayer seeking the credit, the name of the seller of the heavy duty vehicle, 10
the VIN, purchase date, and price of the heavy duty vehicle; 11
(3) a copy of the current Utah vehicle registration in the name of the qualified taxpayer 12
seeking the credit; and 13
(4) the certification required under Subsections 59-7-618.1(2)(b) and 59-10-1033.1(2)(b). 14
15
KEY: air pollution, alternative fuels, tax credits, heavy duty vehicles 16
Date of Enactment or Last Substantive Amendment: August 3, 2017 17
Notice of Continuation: August 5, 2020 18
Authorizing, and Implemented or Interpreted Law: 19-2-104; 19-1-402; 59-7-618.1; 59-10-19
1033.1 20
Page 2 of 2

ITEM 6

195 North 1950 West • Salt Lake City, Utah Mailing Address: P.O. Box 144820 • Salt Lake City, Utah 84114-4820 Telephone [phone] • Fax [phone] • T.D.D. 800 346-3128 www.deq.utah.gov Printed on 100% recycled paper
State of Utah

Department of
Environmental Quality

Tim Davis Executive Director
DIVISION OF AIR QUALITY Bryce C. Bird Director
SPENCER J. COX Governor DEIDRE HENDERSON Lieutenant Governor
.DAQ-038-25
M E M O R A N D U M TO: Air Quality Board THROUGH: Bryce C. Bird, Executive Secretary THROUGH: Jazmine Lopez, Rules Coordinator FROM: Glade Sowards, Environmental Scientist DATE: April 21, 2025 SUBJECT: PROPOSE FOR PUBLIC COMMENT: Amend R307-230. NOx Emission Limits for
Natural Gas-Fired Water Heaters. ______________________________________________________________________________________
During the 2025 General Session, the Utah State Legislature passed House Bill 313 (H.B. 313), Construction Industry Amendments, which amended Utah State Code 19-2-107.7 to limit the applicability of the nitrogen oxide emission limits for natural gas-fired water heaters from applying statewide to only
PM2.5 and ozone nonattainment areas in the state. Rule R307-230 must be amended to reflect the applicability limitations found in Subsection 19-2-107.7(4) as amended in H.B. 313, which will go into effect on July 1, 2025.
Recommendation: Staff recommends the Board approve the amendments to R307-230, NOx Emission Limits for Natural Gas-Fired Water Heaters, for a 30-day public comment period.
State of Utah
Administrative Rule Analysis
Revised May 2024
NOTICE OF SUBSTANTIVE CHANGE
TYPE OF FILING: Amendment
Rule or Section Number: R307-230 Filing ID: Office Use Only
Date of Previous Publication (Only for CPRs): Click or tap to enter a date.

Agency Information
1. Title catchline: Environmental Quality, Air Quality
Building: Multi-Agency State Office Building
Street address: 195 N 1950 W
City, state: Salt Lake City, UT
Mailing address: PO Box 144820
City, state and zip: Salt Lake City, UT 84114-4820
Contact persons:
Name: Phone: Email:
Glade Sowards 801 536-4020 [e-mail]
Jazmine Lopez 801-536-4050 [e-mail]

Please address questions regarding information on this notice to the persons listed above.

General Information
2. Rule or section catchline:
R307-230. NOx Emission Limits for Natural Gas-Fired Water Heaters.

3. Purpose of the new rule or reason for the change:
During the 2025 General Session, the Utah State Legislature passed H.B.313, Construction Industry Amendments, which
amended Subsection 19-2-107.7 to limit the applicability of the NOx emission limits for natural gas-fired water heaters to only
ozone and PM2.5 nonattainment areas (instead of applying statewide). R307-230 is being amended to align with this statute
change.

4. Summary of the new rule or change:
This amendment adds clarifying language to the existing rule.

Fiscal Information
5. Provide an estimate and written explanation of the aggregate anticipated cost or savings to:
A) State budget:
There is no anticipated cost or savings to the State Budget associated with this rule amendment because this amendment only
adds clarifying language to the existing rule.

B) Local governments:
There may be a very small cost savings for local governments in attainment areas that purchase residential water heaters for
their facilities. Ultra-low NOx water heaters have a small estimated price premium over conventional water heaters estimated in
2018 to be $27.52 on average per unit.

C) Small businesses ("small business" means a business employing 1-49 persons):
There may be a very small cost savings for small businesses in attainment areas that purchase residential water heaters for
their facilities. Ultra-low NOx water heaters have a small estimated price premium over conventional water heaters estimated in
2018 to be $27.52 on average per unit.

D) Non-small businesses ("non-small business" means a business employing 50 or more persons):
There may be a very small cost savings for non-small businesses in attainment areas that purchase residential water heaters for
their facilities. Ultra-low NOx water heaters have a small estimated price premium over conventional water heaters estimated in
2018 to be $27.52 on average per unit.

E) Persons other than small businesses, non-small businesses, state, or local government entities ("person" means any
individual, partnership, corporation, association, governmental entity, or public or private organization of any character other
than an agency):
There may be a very small cost savings for persons in attainment areas that purchase residential water heaters for their
facilities. Ultra-low NOx water heaters have a small estimated price premium over conventional water heaters estimated in 2018
to be $27.52 on average per unit.

F) Compliance costs for affected persons (How much will it cost an impacted entity to adhere to this rule or its changes?):
There are no new compliance costs associated with this rule change, but there may be a small compliance cost savings for
parties located in attainment areas.

G) Regulatory Impact Summary Table (This table only includes fiscal impacts that could be measured. If there are
inestimable fiscal impacts, they will not be included in this table. Inestimable impacts will be included in narratives above.)
Regulatory Impact Table
Fiscal Cost FY2025 FY2026 FY2027
State Government $0 $0 $0
Local Governments $0 $0 $0
Small Businesses $0 $0 $0
Non-Small Businesses $0 $0 $0
Other Persons $0 $0 $0
Total Fiscal Cost $0 $0 $0
Fiscal Benefits FY2025 FY2026 FY2027
State Government $0 $0 $0
Local Governments $0 $0 $0
Small Businesses $0 $0 $0
Non-Small Businesses $0 $0 $0
Other Persons $0 $0 $0
Total Fiscal Benefits $0 $0 $0
Net Fiscal Benefits $0 $0 $0
H) Department head comments on fiscal impact and approval of regulatory impact analysis:
The Executive Director of the Department of Environmental Quality, Tim Davis, has reviewed and approved this regulatory
impact analysis.

Citation Information
6. Provide citations to the statutory authority for the rule. If there is also a federal requirement for the rule, provide a
citation to that requirement:
Section 19-2-101
Section 19-2-104
Section 19-2-107.7 Subsection 19-2-107.7(4)

Incorporations by Reference Information
7. Incorporations by Reference (if this rule incorporates more than two items by reference, please include additional tables):
A) This rule adds or updates the following title of materials incorporated by references (a copy of materials incorporated
by reference must be submitted to the Office of Administrative Rules; if none, leave blank):
Official Title of Materials Incorporated
(from title page)
Utah State Code, Utah Air Conservation Act, Subsection 19-2-107.7(4)
Publisher Utah State Legislature
Issue Date Effective date: July 1, 2025
Issue or Version

B) This rule adds or updates the following title of materials incorporated by references (a copy of materials incorporated
by reference must be submitted to the Office of Administrative Rules; if none, leave blank):
Official Title of Materials Incorporated
(from title page)

Publisher
Issue Date
Issue or Version

Public Notice Information
8. The public may submit written or oral comments to the agency identified in box 1. (The public may also request a
hearing by submitting a written request to the agency. See Section 63G-3-302 and Rule R15-1 for more information.)
A) Comments will be accepted until: June 30, 2025
B) A public hearing (optional) will be held:
Date (mm/dd/yyyy): Time (hh:mm AM/PM): Place (physical address or URL):
06/17/2025 02:00 PM - 03:00 PM A public hearing is set for Tuesday, June 17, 2025.

Further details may be found below. The hearing will be cancelled should
no request for one be made by Friday, June 13, 2025, at 10AM MT. The
final status of the public hearing will be posted on Friday, June 13,
after 10:00AM MT. The status of the public hearing may be checked at the
following website location under the corresponding rule.

https://deq.utah.gov/public-notices-archive/air-quality-rule-plan-changes-
open-public-comment

Interested Persons can participate in person or electronically, via the
internet.

In Person:

MASOB
195 N. 1950 W. Salt Lake City, UT, 84116,
First Floor, Air Quality Board Room 1015

Virtual Attendance:

Time zone: America/Denver

Google Meet joining info

Video call link:: https://meet.google.com/wrh-ftdy-vwm

Join by phone:
(US) [phone]
PIN: 189 080 935#

To the agency: If more than one hearing will take place, continue to add rows.

9. This rule change MAY become effective on: August 6, 2025
NOTE: The date above is the date the agency anticipates making the rule or its changes effective. It is NOT the effective date.

Agency Authorization Information
To the agency: Information requested on this form is required by Sections 63G-3-301, 63G-3-302, 63G-3-303, and 63G-3-402.
Incomplete forms will be returned to the agency for completion, possibly delaying publication in the Utah State Bulletin and
delaying the first possible effective date.
Agency head or
designee and title:
Bryce C. Bird, Director, Division of Air
Quality
Date: 4/17/2025

R307. Environmental Quality, Air Quality. 1
R307-230. NOx Emission Limits for Natural Gas-Fired 2
Water Heaters. 3
R307-230-1. Purpose. 4
The purpose of R307-230 is to reduce emissions of nitrogen oxides (NOx) from natural 5
gas-fired water heaters. 6
7
R307-230-2. Applicability. 8
R307-230 applies to the sale or installation of natural gas-fired water heaters on or after 9
July 1, 2018, as limited by Subsection 19-2-107.7(4). 10
11
R307-230-3. Emission Limits and Requirements. 12
(1) The State Construction and Fire Codes Act, Subsection 15A-6-102, Enacted by13
Chapter 236, 2017 General Session, is hereby incorporated by reference. 14
(2) Manufacturers shall use the South Coast Air Quality Management District Method15
100.1 to comply with the NOx emission limits. 16
17
KEY: water heaters, natural gas, NOx, air 18
quality 19
Date of Last Change: August 3, 2017 20
Notice of Continuation: July 12, 2022 21
Authorizing, and Implemented or Interpreted Law: 19-2-101; 19-2-104; 19-2-107.7 22
Page 1 of 1

ITEM 7
Air Toxics

195 North 1950 West • Salt Lake City, Utah
Mailing Address: P.O. Box 144820 • Salt Lake City, Utah 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

DAQA-108-25

M E M O R A N D U M

TO: Air Quality Board

FROM: Bryce C. Bird, Executive Secretary

DATE: February 4, 2025

SUBJECT: Air Toxics, Lead-Based Paint, and Asbestos (ATLAS) Section Compliance Activities –
January 2025
______________________________________________________________________________________

Asbestos Demolition/Renovation NESHAP Inspections 12
Asbestos AHERA Inspections 11
Asbestos State Rules Only Inspections 4
Asbestos Notification Forms Accepted 170
Asbestos Telephone Calls 391
Asbestos Individuals Certifications Approved 88
Asbestos Company Certifications 9
Asbestos Alternate Work Practices Approved 4
Lead-Based Paint (LBP) Inspections 9
LBP Notification Forms Approved 3
LBP Telephone Calls 61
LBP Letters Prepared and Mailed 0
LBP Courses Reviewed/Approved 0
LBP Course Audits 1
LBP Individual Certifications Approved 12
DAQA-108-25
Page 2

LBP Firm Certifications 21
Notices of Violation Sent 0
Compliance Advisories Sent 6
Warning Letters Sent 6
Settlement Agreements Finalized 0

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

Department of
Environmental Quality

Tim Davis
Interim Executive Director

DIVISION OF AIR QUALITY
Bryce C. Bird
Director

SPENCER J. COX
Governor

DEIDRE HENDERSON
Lieutenant Governor
DAQA-161-25

M E M O R A N D U M

TO: Air Quality Board

FROM: Bryce C. Bird, Executive Secretary

DATE: March 4, 2025

SUBJECT: Air Toxics, Lead-Based Paint, and Asbestos (ATLAS) Section Compliance Activities –
February 2025
______________________________________________________________________________________

Asbestos Demolition/Renovation NESHAP Inspections 10
Asbestos AHERA Inspections 10
Asbestos State Rules Only Inspections 7
Asbestos Notification Forms Accepted 142
Asbestos Telephone Calls 411
Asbestos Individuals Certifications Approved 130
Asbestos Company Certifications 12
Asbestos Alternate Work Practices Approved 1
Lead-Based Paint (LBP) Inspections 4
LBP Notification Forms Approved 2
LBP Telephone Calls 76
LBP Letters Prepared and Mailed 3
LBP Courses Reviewed/Approved 0
LBP Course Audits 3
LBP Individual Certifications Approved 26
DAQA-161-25
Page 2

LBP Firm Certifications 17
Notices of Violation Sent 0
Compliance Advisories Sent 3
Warning Letters Sent 2
Settlement Agreements Finalized 0

195 North 1950 West • Salt Lake City, Utah
Mailing Address: P.O. Box 144820 • Salt Lake City, Utah 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

Tim Davis
Interim Executive Director

DIVISION OF AIR QUALITY
Bryce C. Bird
Director

DAQA-263-25

M E M O R A N D U M

TO: Air Quality Board

FROM: Bryce C. Bird, Executive Secretary

DATE: April 2, 2025

SUBJECT: Air Toxics, Lead-Based Paint, and Asbestos (ATLAS) Section Compliance Activities –
March 2025
______________________________________________________________________________________

Asbestos Demolition/Renovation NESHAP Inspections 26
Asbestos AHERA Inspections 26
Asbestos State Rules Only Inspections 8
Asbestos Notification Forms Accepted 173
Asbestos Telephone Calls 349
Asbestos Individuals Certifications Approved 109
Asbestos Company Certifications 13
Asbestos Alternate Work Practices Approved 1
Lead-Based Paint (LBP) Inspections 2
LBP Notification Forms Approved 2
LBP Telephone Calls 82
LBP Letters Prepared and Mailed 19
LBP Courses Reviewed/Approved 0
LBP Course Audits 2
LBP Individual Certifications Approved 29
DAQA-263-25
Page 2

LBP Firm Certifications 18
Notices of Violation Sent 0
Compliance Advisories Sent 11
Warning Letters Sent 1
Settlement Agreements Finalized 4
Penalties Agreed to:
Daw Construction Group LLC/Mitchell Curtis $2,250.00
New Element Construction/Stephanie Juncker $312.50
A-1 Abatement/Tyler Crook $1,500.00
ServiceMaster of Salt Lake/Robert M Fairbanks $2,300.00
Total: $6,362.50
Compliance

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

Department of
Environmental Quality

Kimberly D. Shelley
Executive Director

DIVISION OF AIR QUALITY
Bryce C. Bird
Director

SPENCER J. COX
Governor

DEIDRE HENDERSON
Lieutenant Governor
DAQC-127-25

M E M O R A N D U M

TO: Air Quality Board

FROM: Bryce C. Bird, Executive Secretary

DATE: February 5, 2025

SUBJECT: Compliance Activities – January 2025
_____________________________________________________________________________________

ACTIVITIES:
Activity Monthly Total 36-Month Average
Inspections 85 63
On-Site Stack Test & CEM Audits 1 5
Stack Test & RATA Report Reviews 52 38
Emission Report Reviews 24 20
Temporary Relocation Request Reviews 5 6
Fugitive Dust Control Plan Reviews 115 122
Soil Remediation Report Reviews 1 2
Open Burn Permits Issued 235 654
Miscellaneous Inspections1 11 16
Complaints Received 15 21
Wood Burning Complaints Received 8 3
Breakdown Reports Received 0 1
Compliance Actions Resulting from a Breakdown 0 0
VOC Inspections (Gas station vapor recovery) 0 0
Warning Letters Issued 2 2
Notices of Violation Issued 0 0
Compliance Advisories Issued 6 6
No Further Action Letters Issued 3 2
Settlement Agreements Reached 2 2
Penalties Assessed $7,624 $196,556.85
1Miscellaneous inspections include, e.g., surveillance, complaint, on-site training, dust patrol, smoke patrol, open
burning, etc.
DAQC-127-25
Page 2

SETTLEMENT AGREEMENTS:
Party Amount
Rulon Harper Construction – Pit #12 $7,153
Staker Parson/Western Rock – Cedar City $471

UNRESOLVED NOTICES OF VIOLATION:
Party Date Issued
Citation Oil and Gas (in administrative litigation) 01/15/2020
Uinta Wax Operating (formerly CH4 Finley) 07/24/2020
Finley Resources 09/15/2022
Holcim 12/19/2023
Holcim 03/27/2024
Big West Oil 07/19/2024
Holcim 08/02/2024
Flowers Bakeries, LLC 09/17/2024
Big West Oil 10/01/2024

195 North 1950 West • Salt Lake City, Utah
Mailing Address: P.O. Box 144820 • Salt Lake City, Utah 84114-4820
Telephone [phone] • Fax [phone] • T.D.D. 800 346-3128
www.deq.utah.gov
Printed on 100% recycled paper
State of Utah

Department of
Environmental Quality

Tim Davis
Interim Executive Director

DIVISION OF AIR QUALITY
Bryce C. Bird
Director

SPENCER J. COX
Governor

DEIDRE HENDERSON
Lieutenant Governor
DAQC-263-25

M E M O R A N D U M

TO: Air Quality Board

FROM: Bryce C. Bird, Executive Secretary

DATE: March 7, 2025

SUBJECT: Compliance Activities – February 2025
_____________________________________________________________________________________

ACTIVITIES:
Activity Monthly Total 36-Month Average
Inspections 86 64
On-Site Stack Test & CEM Audits 1 5
Stack Test & RATA Report Reviews 18 39
Emission Report Reviews 38 20
Temporary Relocation Request Reviews 6 6
Fugitive Dust Control Plan Reviews 136 121
Soil Remediation Report Reviews 1 2
Open Burn Permits Issued 402 660
Miscellaneous Inspections1 23 16
Complaints Received 34 21
Wood Burning Complaints Received 6 3
Breakdown Reports Received 0 1
Compliance Actions Resulting from a Breakdown 0 0
VOC Inspections (Gas station vapor recovery) 0 0
Warning Letters Issued 1 2
Notices of Violation Issued 1 0
Compliance Advisories Issued 2 6
No Further Action Letters Issued 1 2
Settlement Agreements Reached 3 2
Penalties Assessed $4,087 $196,477.76
1Miscellaneous inspections include, e.g., surveillance, complaint, on-site training, dust patrol, smoke patrol, open
burning, etc.
DAQC-263-25
Page 2

SETTLEMENT AGREEMENTS:
Party Amount
Whitaker Construction – Plymouth $471
Lakeview Rock Products $1,456
Intrepid Potash – Wendover $2,160

UNRESOLVED NOTICES OF VIOLATION:
Party Date Issued
Citation Oil and Gas (in administrative litigation) 01/15/2020
Ovintiv Production Inc. 07/14/2020
Uinta Wax Operating (formerly CH4 Finley) 07/24/2020
Finley Resources 09/15/2022
Holcim 12/19/2023
Holcim 03/27/2024
Big West Oil 07/19/2024
Holcim 08/02/2024
Flowers Bakeries, LLC 09/17/2024
Big West Oil 10/01/2024
CKC Operations, LLC 02/18/2025
Green Natural Gas Ventures, LLC – Lisbon Valley 02/24/2025

195 North 1950 West • Salt Lake City, Utah
Mailing Address: P.O. Box 144820 • Salt Lake City, Utah 84114-4820
Telephone [phone] • Fax [phone] • T.D.D. 800 346-3128
www.deq.utah.gov
Printed on 100% recycled paper
State of Utah

Department of
Environmental Quality

Tim Davis
Interim Executive Director

DIVISION OF AIR QUALITY
Bryce C. Bird
Director

SPENCER J. COX
Governor

DEIDRE HENDERSON
Lieutenant Governor
DAQC-344-25

M E M O R A N D U M

TO: Air Quality Board

FROM: Bryce C. Bird, Executive Secretary

DATE: April 4, 2025

SUBJECT: Compliance Activities – March 2025
_____________________________________________________________________________________

ACTIVITIES:
Activity Monthly Total 36-Month Average
Inspections 71 64
On-Site Stack Test & CEM Audits 15 5
Stack Test & RATA Report Reviews 32 39
Emission Report Reviews 24 20
Temporary Relocation Request Reviews 11 6
Fugitive Dust Control Plan Reviews 148 120
Soil Remediation Report Reviews 2 2
Open Burn Permits Issued 744 671
Miscellaneous Inspections1 16 16
Complaints Received 32 21
Wood Burning Complaints Received 1 3
Breakdown Reports Received 3 1
Compliance Actions Resulting from a Breakdown 0 0
VOC Inspections (Gas station vapor recovery) 0 0
Warning Letters Issued 1 2
Notices of Violation Issued 0 0
Compliance Advisories Issued 2 6
No Further Action Letters Issued 2 2
Settlement Agreements Reached 2 2
Penalties Assessed $2,631 $196,415.79
1Miscellaneous inspections include, e.g., surveillance, complaint, on-site training, dust patrol, smoke patrol, open
burning, etc.
DAQC-344-25
Page 2

SETTLEMENT AGREEMENTS:
Party Amount
Deluxe Manufacturing Operations $471
Pepperidge Farm, Inc. $2,160

UNRESOLVED NOTICES OF VIOLATION:
Party Date Issued
Citation Oil and Gas (in administrative litigation) 01/15/2020
Ovintiv Production Inc. 07/14/2020
Uinta Wax Operating (formerly CH4 Finley) 07/24/2020
Finley Resources 09/15/2022
Holcim 12/19/2023
Holcim 03/27/2024
Big West Oil 07/19/2024
Holcim 08/02/2024
Big West Oil 10/01/2024
CKC Operations, LLC 02/18/2025
Green Natural Gas Ventures, LLC – Lisbon Valley 02/24/2025

Monitoring
Utah Division of Air Quality
0
10
20
30
40
50
60
70
80
90
100
12345678910111213141516171819202122232425262728293031
PM
2.
5
(µ
g
/
m
3)
Days
Utah 24-Hr PM2.5 Data January 2025
Brigham City Bountiful Copperview Erda
Harrisville Hawthorne Lindon Near road
Rose Park Roosevelt Spanish Fork Smithfield
Environmental Quality Vernal 24-hr Exceedence Value is 35 µg/m3 Heber
Exceedence Value is 35 µg/m3
*Environmental Quality (EQ) previously named Technical Support Center (TSC)
*
BG BV CV ED HB HV HW LN NR RP RS SF SM EQ V4
Arith Mean 67945681111988685
Max 24-hr Avg 19 21 25 14 16 18 22 29 30 27 35 29 13 24 18
98th percentile 18 19 23 12 12 16 20 29 27 24 33 27 13 23 17
Days of Data 29 31 31 31 31 31 31 31 31 31 31 31 31 31 31
Days >35 µg/m3 000000000010000
Utah Division of Air Quality
0
10
20
30
40
50
60
70
80
90
100
12345678910111213141516171819202122232425262728293031
PM
2.
5
(µ
g
/
m
3)
Days
Utah 24-Hr PM2.5 Data February 2025
Brigham City Bountiful Copperview Erda
Harrisville Hawthorne Lindon Near road
Rose Park Roosevelt Spanish Fork Smithfield
Environmental Quality Vernal 24-hr Exceedence Value is 35 µg/m3 Heber
Exceedence Value is 35 µg/m3
*Environmental Quality (EQ) previously named Technical Support Center (TSC)
*
BG BV CV ED HB HV HW LN NR RP RS SF SM EQ V4
Arith Mean 556545567644654
Max 24-hr Avg 14 11 13 26 7 12 12 13 17 15 26 8 21 13 11
98th percentile 12 10 12 18 7 12 10 12 16 14 17 7 17 11 10
Days of Data 28 28 28 25 28 24 28 28 28 28 28 28 28 28 28
Days >35 µg/m3 000000000000000
Utah Division of Air Quality
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
12345678910111213141516171819202122232425262728293031
PM
2.
5
(µ
g
/
m
3)
Days
Utah 24-Hr PM2.5 Data March 2025
Brigham City Bountiful Copperview Erda
Harrisville Hawthorne Lindon Near road
Rose Park Roosevelt Spanish Fork Smithfield
Environmental Quality Vernal 24-hr Exceedence Value is 35 µg/m3 Heber
Exceedence Value is 35 µg/m3
*Environmental Quality (EQ) previously named Technical Support Center (TSC)
*
BG BV CV ED HB HV HW LN NR RP RS SF SM EQ V4
Arith Mean 456444667645564
Max 24-hr Avg 29 25 28 25 11 27 24 22 26 26 8 21 27 24 12
98th percentile 19 20 23 15 10 20 21 20 22 21 7 17 20 18 9
Days of Data 31 31 31 31 31 31 31 31 31 31 31 31 31 31 31
Days >35 µg/m3 000000000000000
Utah Division of Air Quality
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
12345678910111213141516171819202122232425262728293031
PM
2.
5
(µ
g
/
m
3)
Days
Utah 24-Hr PM2.5 Data April 2025
Brigham City Bountiful Copperview Erda
Harrisville Hawthorne Lindon Near road
Rose Park Roosevelt Spanish Fork Smithfield
Environmental Quality Vernal 24-hr Exceedence Value is 35 µg/m3 Heber
Exceedence Value is 35 µg/m3
*Environmental Quality (EQ) previously named Technical Support Center (TSC)
*
BG BV CV ED HB HV HW LN NR RP RS SF SM EQ V4
Arith Mean 566555678766565
Max 24-hr Avg 16 14 14 13 11 14 13 14 15 17 15 14 12 16 15
98th percentile 13 13 13 12 10 13 13 14 15 15 14 14 11 14 14
Days of Data 23 23 23 23 23 23 23 23 23 23 23 23 23 23 23
Days >35 µg/m3 000000000000000
Utah Division of Air Quality
0
50
100
150
200
250
300
350
400
12345678910111213141516171819202122232425262728293031
PM
10
(µ
g
/
m
3)
Days
Utah 24-hr PM10 Data January 2025
Herriman #3 Hawthorne Harrisville Lindon Roosevelt Environmental Quality 24-hr Exceedance Value is 150 ug/m3
Exceedance Value is 150 ug/m3
*
*EnvironmentalQuality (EQ) previously named Technical Support Center (TSC)
H3 HW HV LN RS EQ
Arith Mean 15 21 12 23 13 28Max 24-hr Avg 43 43 31 90 42 92Days of Data 31 31 31 31 31 31Days >150 µg/m 3 000000
Utah Division of Air Quality
0.0
50.0
100.0
150.0
200.0
250.0
300.0
350.0
400.0
12345678910111213141516171819202122232425262728293031
PM
10
(µ
g
/
m
3)
Days
Utah 24-hr PM10 Data February 2025
Herriman #3 Hawthorne Harrisville Lindon Roosevelt Environmental Quality 24-hr Exceedance Value is 150 ug/m3
Exceedance Value is 150 ug/m3
*
*EnvironmentalQuality (EQ) previously named Technical Support Center (TSC)
H3 HW HV LN RS EQ
Arith Mean 19 17 13 15 12 25Max 24-hr Avg 94 56 65 46 55 91Days of Data 28 28 28 28 25 28
Days >150 µg/m 3 000000
Utah Division of Air Quality
0.0
50.0
100.0
150.0
200.0
250.0
300.0
350.0
400.0
12345678910111213141516171819202122232425262728293031
PM
10
(µ
g
/
m
3)
Days
Utah 24-hr PM10 Data March 2025
Herriman #3 Hawthorne Harrisville Lindon Roosevelt Environmental Quality 24-hr Exceedance Value is 150 ug/m3
Exceedance Value is 150 ug/m3
*
*Environmental Quality (EQ) previously named Technical Support Center (TSC)
H3 HW HV LN RS EQ
Arith Mean 18 17 13 17 12 24Max 24-hr Avg 108 83 100 79 62 97Days of Data 31 31 31 31 31 31
Days >150 µg/m 3 000000
Utah Division of Air Quality
0.0
50.0
100.0
150.0
200.0
250.0
300.0
350.0
400.0
12345678910111213141516171819202122232425262728293031
PM
10
(µ
g
/
m
3)
Days
Utah 24-hr PM10 Data April 2025
Herriman #3 Hawthorne Harrisville Lindon Roosevelt Environmental Quality 24-hr Exceedance Value is 150 ug/m3
Exceedance Value is 150 ug/m3
*
*EnvironmentalQuality (EQ) previously named Technical Support Center (TSC)
H3 HW HV LN RS EQ
Arith Mean 22 15 15 18 16 22Max 24-hr Avg 56 30 37 37 46 45Days of Data 23 23 23 23 23 23
Days >150 µg/m 3 000000
5.7
13.3
13.4
11.4
5.4 4.5
5.7
4.4 3.8
5.4
1.8 1.1 0.6 3.4
6.1 6.5
2.2 0.0 0.5
-4.0
2.2 1.5
3.52.5
-0.5
2.1 2.7
4.1 4.3
8.0
8.4
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
0.110
0.120
1 2 3 4 5 6 7 8 9 10111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature January 2025
Bountiful Copperview Erda Herriman #3 Harrisville Hawthorne Near Road Red Butte Rose Park Environmental Quality Exceed.TM*
*Environmental Quality (EQ) previously named Technical Support Center (TSC)
** Controlling Monitor
**
O3 JAN 2024 BV CV ED H3 HV HW NR RB RP EQ
Arith Mean .032 .032 .035 .033 .034 .029 .027 .037 .031 .029
8 -hr. Ozone 4th Max .040 .039 .040 .038 .041 .035 .035 .041 .037 .035
Days of Data 31 31 31 31 31 31 31 31 31 31
Days > 0.070 0000 000000
-1.4
4.8
4.4 6.0 3.7
1.8
2.0
-1.5
2.8
-1.1
4.4
0.3
-2.4
-1.30.3
2.0
5.8
-1.8
-4.9
-8.1
-7.6
0.7 -0.8 -0.2
-2.7 -1.7
-5.8 -4.7
-3.1
-0.4 -0.4
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.020
0.040
0.060
0.080
0.100
0.120
12345678910111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature January 2025
Price #2 Roosevelt Vernal Exceed.TM
P2 RS V4
Arith Mean .035 .036 .037
8 -hr. Ozone 4th Max .040 .045 .043
Days of Data 31 31 31
Days > 0.070 000
0.5
7.6
7.4
3.62.7 3.5
1.9 0.0
1.7
0.1
1.3
0.7
-2.6
0.6 3.2
5.0
1.3
-2.7
-2.4
-6.5
-1.2
-0.4
-0.3
3.7
-0.5
0.5 1.0
2.5 4.0 4.8 5.1
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
0.110
0.120
1 2 3 4 5 6 7 8 9 10111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature January 2025
Smithfield Exceed.TM
SM
Arith Mean .035
8 -hr. Ozone 4th Max .041
Days of Data 31
Days > 0.070 0
6.5
10.513.9
9.9
4.3 4.1
5.3 2.5 3.4 3.4 1.71.9
-0.5
1.4 3.2
6.9
5.2
-1.8
-1.5
-4.4
1.5 0.6 1.5
2.6 3.3 2.2
2.8 2.8
3.8 4.9
8.3
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
12345678910111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature January 2025
Lindon Spanish Fork Exceed.TM
LN SF
Arith Mean .030 .032
8 -hr. Ozone 4th Max .037 .036
Days of Data 31 31
Days > 0.070 00
9.6
13.6
13.2 14.111.4 12.1
8.1
10.1
7.3
8.2 9.16.9 7.0
9.0
11.3 12.4 10.7
6.3 7.1
2.7
5.7
11.4
8.1
9.6
7.0 9.4 8.8 8.4 9.0
12.7 11.9
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature January 2025
Enoch Hurricane Moab Exceed.TM
EN HC M7
Arith Mean .036 .038 .037
8 -hr. Ozone 4th Max .042 .043 .045
Days of Data 31 26 31
Days > 0.070 000
5.7
13.3
13.4
11.4
5.4 4.5 5.7 4.4 3.8 5.4
1.81.1 0.6
3.4
6.1 6.5
2.2
0.0 0.5
-4.0
2.2
1.5
3.5
2.5
-0.5 2.1
2.7
4.1 4.3
8.0 8.4
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
1 2 3 4 5 6 7 8 9 10111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature January 2025
Stations Monitoring the Inland Port Development
ZZ Lake Park Exceed.TM
*ZZ is located at the New Utah State Prison (1480 North 8000 West, SLC).
This site was previously named IP
*
ZZ LP
Arith Mean .035 .034
8 -hr. Ozone 4th Max .041 .039
Days of Data 31 31
Days > 0.070 00
0.5
7.6
7.4
3.62.7
3.5
1.9 0.0
1.7
0.1 1.30.7
-2.6
0.6
3.2 5.0
1.3
-2.7 -2.4
-6.5
-1.2
-0.4 -0.3
3.7
-0.5
0.5
1.0
2.5 4.0
4.8 5.1
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
1 2 3 4 5 6 7 8 9 10111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature January 2025
Brigham city Exceed.TM
BG
Arith Mean .034
8 -hr. Ozone 4th Max .040
Days of Data 31
Days > 0.070 0
1.9
6.88.6 8.2
1.0
2.0
1.0 -0.5
1.0
0.8
-0.3
0.0
-2.4
-1.7
2.7
6.0
3.2
-3.9 -2.8
-6.9
-1.1
-0.9 -0.1
3.7
-2.0
-2.2
-0.3
1.6 2.9
4.0
7.4
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature January 2025
Heber Exceed.TM
HB
Arith Mean .031
8 -hr. Ozone 4th Max .035
Days of Data 31
Days > 0.070 0
8.7
17.0 18.8 19.2
15.1
6.8
12.5
5.2 4.4 3.6
-3.0
-1.0
5.9
10.2
4.2
6.2 8.1 6.0 6.9
3.1
5.4
10.4
12.6
18.7
11.4
8.5
14.3 12.5
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
0.110
0.120
1 2 3 4 5 6 7 8 9 10111213141516171819202122232425262728293031
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u
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T
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p
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a
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(
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature February 2025
Bountiful Copperview Erda Herriman #3 Harrisville Hawthorne
Near Road Red Butte Rose Park Environmental Quality Exceed.TM
BV CV ED H3 HV HW
NR RB RP EQ
*
*Environmental Quality (EQ) previously named Technical Support Center (TSC)
** Controlling Monitor
**
O3 FEB 2025 BV CV ED H3 HV HW NR RB RP EQ
Arith Mean .038 .039 .039 .037 .038 .035 .035 .041 .038 .035
8 -hr. Ozone 4th Max .043 .042 .043 .047 .044 .039 .038 .044 .041 .039
Days of Data 28 28 28 28 28 28 28 28 28 28
Days > 0.070 0000000000
6.59.2
14.0
11.5
13.6 12.814.1
5.0
2.6 1.8 -0.9
-3.0
-5.6
2.1
5.4
2.4
7.9 6.3
4.4
1.8
7.7
7.2
10.7
16.7 14.6
7.4 9.9
13.4
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.020
0.040
0.060
0.080
0.100
0.120
12345678910111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature February 2025
Price #2 Roosevelt Vernal Exceed.TM
P2 RS V4
Arith Mean .044 .042 .043
8 -hr. Ozone 4th Max .049 .051 .047
Days of Data 28 28 28
Days > 0.070 000
5.1
12.5 14.6
17.0
13.5
0.3
8.9
-0.5 0.6 0.9
-4.1
-4.5 -5.4
4.7
2.0 0.4
5.8 3.5
3.20.7 2.2 0.1 3.0
9.9
7.0
4.5 5.0
5.8
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
0.110
0.120
12345678910111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature February 2025
Smithfield Exceed.TM
SM
Arith Mean .042
8 -hr. Ozone 4th Max .049
Days of Data 28
Days > 0.070 0
8.1
15.517.4 17.5
13.7 14.4
12.0
4.9 3.8 4.2
-2.2-1.7
4.2
8.2
3.0
5.7 6.4
5.7
5.9
3.4 3.5
6.6
13.0
17.3
12.8
8.5 11.5
13.6
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
12345678910111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature February 2025
Lindon Spanish Fork Exceed.TM
LN SF
Arith Mean .038 .038
8 -hr. Ozone 4th Max .042 .042
Days of Data 28 28
Days > 0.070 00
14.4
18.720.5
22.7
18.9 19.1
17.7 15.2
12.5 14.3
12.1
7.5
5.9
10.7
12.6 13.5
15.2
14.4 14.914.1
14.4 16.2
19.2
22.7 23.9
16.6
19.7
21.2
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature February 2025
Enoch Hurricane Moab Exceed.TM
EN HC M7
Arith Mean .042 .041 .046
8 -hr. Ozone 4th Max .046 .046 .050
Days of Data 28 28 28
Days > 0.070 000
8.7
17.018.8 19.2
15.1
6.8
12.5
5.2 4.4
3.6
-3.0
-1.0
5.9
10.2
4.2 6.2
8.1
6.0 6.9
3.1
5.4
10.4
12.6
18.7
11.4
8.5
14.3
12.5
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
1 2 3 4 5 6 7 8 9 10111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature February 2025
Stations Monitoring the Inland Port Development
ZZ Lake Park Exceed.TM
*ZZ is located at the New Utah State Prison (1480 North 8000 West, SLC).
This site was previously named IP
*
ZZ LP
Arith Mean .039 .040
8 -hr. Ozone 4th Max .043 .042
Days of Data 28 28
Days > 0.070 00
5.1
12.514.6
17.0
13.5
0.3
8.9
-0.5
0.6
0.9
-4.1-4.5 -5.4
4.7
2.0
0.4
5.8
3.5 3.2
0.7
2.2
0.1
3.0
9.9
7.0
4.5
5.0
5.8
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
1 2 3 4 5 6 7 8 9 10111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature February 2025
Brigham city Exceed.TM
BG
Arith Mean .038
8 -hr. Ozone 4th Max .043
Days of Data 28
Days > 0.070 0
5.0
13.4
13.2
14.6
11.7 11.1
9.4
2.5 1.1
2.3
-4.2-4.6
-1.6
5.0
2.0
-0.8
4.2
3.8
1.6 1.8
3.8
4.2
6.8
13.2
11.1
5.9
9.8
12.6
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
12345678910111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature February 2025
Heber Exceed.TM
HB
Arith Mean .042
8 -hr. Ozone 4th Max .048
Days of Data 28
Days > 0.070 0
14.2
18.7
10.1 10.2
11.4
7.4
5
9.5
16.1
17.6
17.615.6
11.9
6
7.4
15.7 17.5
2.5
8.5 9
13.2 14
15.3
18.8
21.1
25.4
23.7
14.4
11.5
14.1
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
0.11
0.12
12345678910111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature March 2025
Bountiful Copperview Erda Herriman #3 Harrisville Hawthorne
Near Road Red Butte Rose Park Environmental Quality Exceed.TM
BV CV ED H3 HV HW
NR RB RP EQ
*
*Environmental Quality (EQ) previously named Technical Support Center (TSC)
** Controlling Monitor
**
O3 March 2025 BV CV ED H3 HV HW NR RB RP EQ
Arith Mean .046 .046 .045 .048 .045 .041 .041 .046 .045 .045
8 -hr. Ozone 4th Max .051 .051 .050 .052 .050 .045 .045 .049 .050 .051
Days of Data 31 31 31 31 31 31 31 31 31 31
Days > 0.070 0000000000
14.4
16
8.2 11.3 8.5
6.2
5.2
8
11.7
15
15 14.2
10.7
5.7
6.5
13.6 15.3
6.7 7.410
10.1 12.8
14.8
19.4
19.5
22.4
21.9
16.9
10.4 11
14.5
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
0
0.02
0.04
0.06
0.08
0.1
0.12
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature March 2025
Price #2 Roosevelt Vernal Exceed.TM
P2 RS V4
Arith Mean .047 .048 .049
8 -hr. Ozone 4th Max .051 .053 .052
Days of Data 31 31 31
Days > 0.070 000
6.9
8.3
5.5
8
8.4
2.6 3.5
4.5
8.9
13.3 14.3
12
10.6
3
2
13.3 14.6
2.5
4
6.6 8.7
9.6 11.3
16.5
19.3
22.4
20.7
12.9
11.8
8.4 7.9
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
0.11
0.12
1 2 3 4 5 6 7 8 9 10111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature March 2025
Smithfield Exceed.TM
SM
Arith Mean .047
8 -hr. Ozone 4th Max .052
Days of Data 31
Days > 0.070 0
15.2
17.6
7.9 8.3
9.6
4.9
4.3
7.6
14.7 16.3 15.8
13.8
10.1
4.2
4.7
15.5 15.7 13.2
12.6
9.9
11.3 11.8
14
17.6
20.4
24.6
22.4
15.2
11.3
13.8 14.7
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature March 2025
Lindon Spanish Fork Exceed.TM
LN SF
Arith Mean .046 .043
8 -hr. Ozone 4th Max .051 .047
Days of Data 31 31
Days > 0.070 00
23.2
18.8
7.6
14.6
15.6
8.8 9.7
14.3
18.9
20.1
18.9
14.4
12.1
7.1
12.3
15.5
19.1
11.9 12.4
16.6
18.8
19.3
22.8
25.5
28.2
28.5 26.4
19.7
18.5
19.9 19.8
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature March 2025
Enoch Hurricane Moab Exceed.TM
EN HC M7
Arith Mean .048 .047 .045
8 -hr. Ozone 4th Max .056 .054 .053
Days of Data 31 31 31
Days > 0.070 000
14.2
18.7
10.1 10.2
11.4
7.4
5
9.5
16.1 17.6 17.615.6
11.9
6
7.4
15.7
17.5
2.5
8.59
13.2
14 15.3
18.8
21.1
25.423.7
14.4
11.5
14.1
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature March 2025
Stations Monitoring the Inland Port Development
ZZ Lake Park Exceed.TM
*ZZis located at the New Utah State Prison (1480 North 8000 West, SLC).
This site was previously named IP
*
ZZ LP
Arith Mean .045 .045
8 -hr. Ozone 4th Max .050 .051
Days of Data 31 31
Days > 0.070 00
6.9 8.3
5.5
8
8.4
2.6 3.5
4.5
8.9
13.3 14.312
10.6
3 2
13.3
14.6
2.5
4
6.6
8.7
9.6
11.3
16.5
19.3 22.4 20.7
12.9
11.8
8.4 7.9
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
12345678910111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature March 2025
Brigham city Exceed.TM
BG
Arith Mean .045
8 -hr. Ozone 4th Max .051
Days of Data 31
Days > 0.070 0
14.0 14.9
5.1
6.4
7.4
3.3
2.9
6.8
12.7
13.9
12.811.8
8.0
1.6
2.9
11.9
13.4
2.2
3.7
7.6
8.5
9.0
12.0
16.5
19.9 21.7 19.9
14.9
9.1
10.5 10.3
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
12345678910111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature March 2025
Heber Exceed.TM
HB
Arith Mean .050
8 -hr. Ozone 4th Max .055
Days of Data 31
Days > 0.070 0
6.8
8.2
8.7
10.1
12.5
16.7
21.7
20.5 21.3
27.1 28.6
23.1
15
18.4
22.3
20.3
13.3
8.6
12.7
18.7 17.5
19.9
21.5
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
0.110
0.120
1 2 3 4 5 6 7 8 9 10111213141516171819202122232425262728293031
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature April 2025
Bountiful Copperview Erda Herriman #3 Harrisville Hawthorne
Near Road Red Butte Rose Park Environmental Quality Exceed.TM
BV CV ED H3 HV HW
NR RB RP EQ
*
*EnvironmentalQuality (EQ) previously named Technical Support Center (TSC)
** Controlling Monitor
**
O3 March 2025 BV CV ED H3 HV HW NR RB RP EQ
Arith Mean .053 .053 .051 .055 .052 .047 .046 .052 .052 .053
8 -hr. Ozone 4th Max .059 .059 .055 .061 .058 .053 .051 .058 .056 .057
Days of Data 23 23 23 23 23 23 23 23 23 23
Days > 0.070 0000000000
5.6
6
6.9 8.4
9.6
14.8
19.4
19.520.8 21.3
25.5 24.3
19.1
17
21.1 19.5
12.8
6.2
10.5
16.8
17.6 20.3
20.8
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
0.000
0.020
0.040
0.060
0.080
0.100
0.120
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature April 2025
Price #2 Roosevelt Vernal Exceed.TM
P2 RS V4
Arith Mean .055 .056 .056
8 -hr. Ozone 4th Max .061 .063 .065
Days of Data 23 23 23
Days > 0.070 000
4.6
6.5 8.7 9.8
12.9
15.1
18.3
17.2
19
22.3
23.8
20
13.1
17.6
21
20.8
12
7.5
12.1
15.8
14.9
17.1 19
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
0.110
0.120
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature April 2025
Smithfield Exceed.TM
SM
Arith Mean .053
8 -hr. Ozone 4th Max .057
Days of Data 23
Days > 0.070 0
4.5
7.5
6
8.9
12
15
19.9
19.7
21.1
25.5
26.8
23.3
15.1
18.2
22.6
19.6
13.2
8.6
12.3
18.2 18
20.7 22
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature April 2025
Lindon Spanish Fork Exceed.TM
LN SF
Arith Mean .053 .050
8 -hr. Ozone 4th Max .059 .056
Days of Data 23 23
Days > 0.070 00
14.9
11.4
11.7
14.8
16.9
20.7
23.7
26
28.5 30.7
30.3
27.8
26.2
27 27.1
25.7
19.3
11.5
17.7
22.5
25.4
26.4 25.8
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature April 2025
Enoch Hurricane Moab Exceed.TM
EN HC M7
Arith Mean .052 .051 .052
8 -hr. Ozone 4th Max .058 .056 .056
Days of Data 23 23 23
Days > 0.070 000
6.8 8.2
8.7
10.1
12.5
16.7
21.7 20.5
21.3
27.1 28.6
23.1
15
18.4
22.3
20.3
13.3
8.6
12.7
18.7 17.5 19.9
21.5
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature April 2025
Stations Monitoring the Inland Port Development
ZZ Lake Park Exceed.TM
*ZZis located at the New Utah State Prison (1480 North 8000 West, SLC).
This site was previously named IP
*
ZZ LP
Arith Mean .048 .053
8 -hr. Ozone 4th Max .055 .059
Days of Data 23 23
Days > 0.070 00
4.6 6.58.7 9.8
12.9
15.1
18.3 17.2
19 22.3 23.8
20
13.1
17.6
21
20.8
12
7.5
12.1
15.8 14.9 17.1
19
-10
-5
0
5
10
15
20
25
30
35
40
45
50
55
60
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature April 2025
Brigham city Exceed.TM
BG
Arith Mean .054
8 -hr. Ozone 4th Max .059
Days of Data 23
Days > 0.070 0
3.5 4.7
5.8 6.2
10.0
13.6
17.2
17.5
18.8
23.5 24.3
21.1
14.9
19.6 19.6
18.9
7.8
5.7
10.8
15.1
15.8 17.2
19.5
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
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Days
Highest 8-hr Ozone Concentration & Daily Maximum Temperature April 2025
Heber Exceed.TM
HB
Arith Mean .056
8 -hr. Ozone 4th Max .063
Days of Data 23
Days > 0.070 0