AQ-2017-007-R323-324-REPORTTOTHEBOARDOFSUPERVISORS-2021-06-23.PDF

Executive Summary
of the Report to the Board of Supervisors
Prepared by the Maricopa County Air Quality Department
Board Hearing Date: June 23, 2021
Case Number/Title: AQ-2017-007:
Rule 323 (Fuel Burning Equipment from
Industrial/Commercial/Institutional (ICI) Sources)
Rule 324 (Stationary Reciprocating Internal
CombustionEngines (RICE))
Agenda Item: (Pending)
Supervisor Districts: All Districts
The Maricopa County Air Quality Department (MCAQD) complied with all statutory and county policies
throughout this rulemaking process. Per the Enhanced Regulatory Outreach Program (EROP) Policy: “In
addition to the required staff report, an executive summary of the report including an overview of
stakeholder input and staff responses will be provided to the Board of Supervisors at least one week prior to
any Board of Supervisors’ public hearing.”
Overview of the Report to the Board of Supervisors:
On May 4, 2016, portions of Maricopa County were designated as a moderate nonattainment area with
respect to the 2008 National Ambient Air Quality Standards for Ozone. Sections 182(b)(2) and 182(f) of the
Clean Air Act require jurisdictions that are classified as “moderate” or higher nonattainment to implement
reasonably available control technology (RACT) for all categories of volatile organic compound (VOC)
sources covered by a Control Technique Guideline document as well as for all major stationary sources of
NOX and VOCs that are located within the nonattainment area. The U.S. Environmental Protection Agency
(EPA) defines RACT as “the lowest emission limitation that a particular source is capable of meeting by the
application of control technology that is reasonably available considering technological and economic
feasibility.” The EPA provides guidance on RACT for sources of NOX through Alternative Control
Technology documents which offer State and local air pollution control authorities information that assists
in determining NOX-RACT for air quality rules. In addition, the EPA reviews state implementation plan
(SIP)-approved air quality rules from other air districts with ozone nonattainment areas to assist in
determining NOX-RACT for air quality rules.
In November 2016, Rules 323 and 324 were revised to implement RACT for sources of NOX. The revised
rules were submitted to the EPA in June of 2017, as part of the SIP Revision for the Maricopa County Air
Quality Department Ozone Rules contained in the Arizona SIP. The EPA reviewed Rules 323 and 324, and
provided the MCAQD with written rule approvability and rule improvement comments for the rules. EPA
staff informed MCAQD staff they would be using a conditional approval process to act on Rules 323 and
324, and the MCAQD would need to draft a commitment letter outlining revisions to Rules 323 and 324 to
address the rule approvability comments.
On January 28, 2019, the MCAQD submitted a Letter of Commitment for Conditional Approval of the
Maricopa County RACT SIP to the EPA. Later, on December 5, 2019, the MCAQD submitted a
supplemental commitment letter for Rule 324 to address additional rule approvability comments MCAQD
received after the original commitment letter was submitted. Based on the commitment letters, the EPA
published a proposed conditional approval of Rules 323 and 324 in the Federal Register on December 30,
2019 (Docket ID; EPA-R09-OAR-2019-0321). The proposed conditional approval rulemaking was available
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for a 30-day comment period, but no comments were received. The proposed conditional approval outlined
EPA’s official rule approvability comments (“rule deficiencies”) which precluded full approval of the rules
into the Arizona SIP.
EPA’s final conditional approval was published on July 20, 2020. The effective date of the final rule was
August 19, 2020. If the MCAQD, through the ADEQ, submits the rule revisions that the MCAQD has
committed to submit within 12 months and the EPA approves the submission, then the identified
deficiencies will be cured, and the rules will be approved as part of the Arizona SIP. Revisions addressing
the EPA’s identified deficiencies have been made to Rules 323 and 324 and are included in this report.
Overview of Stakeholder Input and Staff Responses:
During the rulemaking process, the MCAQD received written comments from four (4) stakeholders. The
stakeholders expressed neither support nor opposition for the rulemaking. The MCAQD evaluated the
comments and drafted responses. The stakeholder comments and the MCAQD responses to the comments
are listed below.
The following comments and responses are applicable to Rule 323:
Comment #1: This rule contains similar requirements for tracking fuel use and days/hours of operation. I
would like to request the same change as stated above (for R322, section 501.1 - This rule now requires
records of the type and amount of fuel used, sulfur content and days and hours of operation. I would like to
remove the requirement to track days and hours of operation and that fuel use be required to be tracked
monthly. Fuel tracking monthly makes the most sense since invoices are typically sent monthly (in the case
of natural gas). I have been unable to identify a reason to track days and hours of operation. This
information does not appear to be needed to determine compliance).
Response #1: The MCAQD considered your comment and deleted the requirement for days and hours of
operation. In addition, the MCAQD clarified that fuel usage be tracked monthly.
Comment #2: In Maricopa County’s (the County) workshop presentation, the County recommends
accepting the more stringent boiler tuning requirements and suggests requirements based rated capacity and
whether or not the source was at a major source. Concerning the County’s recommendations for altering
requirements based on rated capacity of the unit, [our Company] suggests an alternative. [Our Company]
has reviewed EPA’s comment and believe EPA was intending to apply RACT to “major source units” (units
emitting 100 tons/yr of NOx) and not a minor source unit at a “major source” as suggested by the County’s
proposed commitment. [Our Company] requests that RACT requirements only apply to major source units.
Applying a major source applicability limit would be consistent with EPA’s recommendation with Rule 322.
[Our Company] owns a Clayton Boiler rated at 11 MBtu/hr, which emits approximately 25 lbs per year.
[Our Company] has reviewed the examples for boiler tuning requirements and find them excessive in some
situations for simple and small units. Multiple items in the referenced boiler tuning requirements could not
work for this unit. [Our Company] doesn't support more stringent requirements for the smaller units. At a
minimum, there should be language that accommodate the size and design of the unit.
Response #2: The MCAQD considered your comment and developed a table that clearly outlines which
combustion units at a major source of NOx must comply with RACT requirements, see Table 323-1 in the
draft rule. Some smaller combustion units, units greater than 10 MMBtu/hour and less than or equal to 50
MMBtu/hour with annual heat input less than 220,000 therms, will not have to comply with RACT
requirements.
The following comments and responses are applicable to Rule 324:
Comment #1: The hours of operation for emergencies should be specified in this section and testing,
reliability and maintenance hours should be grouped together as non-emergency hours. Suggested language
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is: “Monthly and rolling twelve-month total hours of operation, emergency hours of operation, and non-
emergency hours of operation (including hours for testing, reliability, and maintenance).”
Response #1: The MCAQD considered your comment and revised the language in Section 502.2 to read as
follows: Operation Records: An owner or operator of a stationary RICE shall maintain records of the
monthly and 12-month rolling total hours of operation for each stationary RICE. For emergency engines,
the operation records shall also include:
a. Monthly and annual hours of operation for reliability related activities such as engine readiness,
calibration, or maintenance, or to prevent the occurrence of an unsafe condition during electrical system
maintenance; and
b. The number of operating hours for emergency use and an explanation for the emergency use.
Comment #2: We recently had several air permit inspections for our general permits that are for our
emergency generators. We have been having these inspections every other year for our facilities and not had
any major issues during the inspections. Each generator has a logbook that has a monthly record for the
checks that take place, any operation or other issues that occur. Historically, these records were used to
calculate the 12-month hours of operation to show compliance with permit conditions. However, during
our recent inspections, we were informed that we had not been keeping a monthly rolling record of hours
and that we needed to begin this for our general permitted sites. I've reviewed the permit and Rule 324 and
understand that this is required but seems like an unnecessary effort if we keep a monthly log of hours. The
previous 12 months can easily be calculated by taking March 2019 hours and subtracting March 2018 hours
to show the current 12 months of hours of operation. [Our Company] emergency generators typically run
less than a couple hours a month, often times even less than a couple hours. [Our Company] understands
the permit language and will do what is needed to maintain compliance. However, since our sites have been
inspected frequently and this has not previously been noted nor has it been noted as a compliance issue.
[Our Company] believes that for remote sites that also run very limited hours that the information needed
to determine hours of operation can be calculated from the on-site logbooks during inspections. Our
emergency generators are typically at unmanned facilities, have limited use and would require additional
effort and resources to collect and track this information. We hope to see this requirement addressed
through logbook information that is maintained at each site and not a requirement to create spreadsheets for
each generator (we have over 30 permitted sites). Since Rule 324 is currently being reviewed and possibly
amended we hope that this issue can be addressed during this process. We would like to see this section
clarified that for limited use, unmanned sites that the on-site logbook can be used to determine the 12-
month hours of operation.
Response #2: The MCAQD considered your comment and determined that records of the 12-month
rolling total hours of operation are needed to ensure compliance with emission and/or operation limits. The
information can be recorded in the logbook or using any other method as long as the required records are
maintained.
Comment #3: We have reviewed the language and our operations across our fleet. We are requesting the
following change to the verbiage (see below). We have engines from 15 different manufactures (some are no
longer in business) and only use a single qualified service provider. The use of one contractor to conduct
engine is preferred by our Supply Chain because of the clearance required to work at some of our sites as
well as safety hazards associated with our facilities. There are some service providers that have safety records
that prohibit them from working at our sites entirely.
An owner or operator of a stationary RICE shall maintain the stationary RICE in accordance with the
manufacturer's written instructions or in accordance with the written maintenance schedule provided by the
manufacturer’s authorized a qualified service provider. If the manufacturer's written instructions are not
available and the manufacturer’s authorized qualified service provider does not provide a written
maintenance schedule, the owner or operator shall conduct preventative maintenance according to the
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following schedule, including all of the following procedures, if the engine is so equipped, and if such
procedures are appropriate to the type of engine:
Response #3: The MCAQD considered your comment and revised the language in Section 302 to read as
follows: MAINTENANCE REQUIREMENTS: An owner or operator of a stationary RICE shall maintain
the stationary RICE in accordance with the manufacturer's written instructions or in accordance with the
maintenance schedule provided by the manufacturer’s authorized service provider. Alternatively, the owner
or operator shall conduct preventative maintenance according to the following schedule, including all of the
following tuning procedures, if the engine is so equipped, and if such procedures are appropriate to the type
of engine.
Comment #4: Thanks for the opportunity to provide comments in your chat room during the October 24,
2019 workshop. I notice of you could not accept a proposed comment [KB-A30] about changing the term
“manufacturer’s authorized service provider” with the term “qualified service provider” because this is not a
recognized term in use by the EPA. We agree with the commenters concern about the term “authorized
service provider” because the term in our opinion raises proprietary issues related to maintenance
documentation provided by engine and/or emergency generator manufacturers exclusively to authorized
dealerships. A regular maintenance provider may have authorizations from various engine manufacturers
but may not be able to get authorizations from for example emergency generator manufacturers who have
their own non-road engines installed. We suggest you consider alterative options and include language in
Section 302 about “or authorization from a manufacturer of a similar engine type” and “in accordance with
recommendations from the manufacturer of a similar engine type.”
Response #4: The MCAQD considered your comment and revised the language in Section 302 to read as
follows: MAINTENANCE REQUIREMENTS: An owner or operator of a stationary RICE shall maintain
the stationary RICE in accordance with the manufacturer's written instructions or in accordance with the
maintenance schedule provided by the manufacturer’s authorized service provider. Alternatively, the owner
or operator shall conduct preventative maintenance according to the following schedule, including all of the
following tuning procedures, if the engine is so equipped, and if such procedures are appropriate to the type
of engine.
Comment #5: I have a few comments for draft Rule 324, which deals explicitly with non-road engines. I
understand the purpose of tracking non-road engines and the amount of time they are onsite to ensure there
is no circumvention of the rules by using a non-road engine as a stationary engine. Unfortunately, the
record-keeping requirement can be quite burdensome for facilities with special events that use non-road
generators for a minimal amount of time. Almost all non-road generators are brought onto the site and
removed in less than a week, and many within 24 hours. Could there be a timeframe, such as seven days,
that if a non-road engine is brought onsite for more than seven days, then section 502.6 applies?
Additionally, the serial number requirement in Section 502.6 b. can be difficult to obtain depending on the
situation. Rental companies will have the make, model, and capacity readily available for the non-road
engines being rented, but not the specific serial number sent to the site. If the non-road engine is brought
onto the site for a single night event, it can be challenging to obtain the serial number for an event that lasts
three hours at night.
Response #5: The MCAQD considered your comments and revised the language in Section 502.6 to read
as follows: Nonroad Engine Records: An owner or operator of a nonroad engine shall maintain the
following records for each non-road engine: a. Date that each engine is brought to the stationary source; and
b. For engines located at a stationary source greater than 14 consecutive days: (1) Make, model, serial
number, and rated capacity (bhp hours) of the engine; and (2) Date of each instance in which the engine is
moved from its existing location, and the reason why the engine was moved; and (3) Fuel type and sulfur
content of the fuel. Additionally, the MCAQD revised the applicability language in Section 102.1.d to clarify
which nonroad engines are subject to the recordkeeping requirements in Rule 324. Section 102.1.d now
reads as follows: Any nonroad engine, with a rated bhp of greater than 125, that is located at a stationary
source that emits or has the potential to emit any regulated air pollutant greater than the permitting
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thresholds defined in Rule 100 of these rules. For the purpose of this Rule, a nonroad engine is any internal
combustion engine that by itself or in or on a piece of equipment is portable or transportable, meaning
designed to be and capable of being carried or moved from one location to another. Indicia of
transportability include but are not limited to, wheels, skids, carrying handles, dollies, trailers, or platforms.
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Report to the Board of Supervisors
Prepared by the Maricopa County Air Quality Department
Board of Health Meeting Date: April 26, 2021
Board Hearing Date: June 23, 2021
Case Number/Title: AQ-2017-007:
Rule 323 (Fuel Burning Equipment from
Industrial/Commercial/Institutional (ICI) Sources)
Rule 324 (Stationary Reciprocating Internal Combustion
Engines (RICE))
Agenda Item: (Pending)
Supervisor Districts: All Districts
Applicant: Staff
Request: Approve revisions to Rule 323 (Fuel Burning Equipment
from Industrial/Commercial/Institutional (ICI) Sources) and
Rule 324 (Stationary Reciprocating Internal Combustion
Engines (RICE)) of the Maricopa County Air Pollution
Control Regulations and approve submission of the revised
rules as a revision to the Arizona State Implementation Plan
(SIP).
On May 4, 2016, portions of Maricopa County were
designated as a moderate nonattainment area with respect to
the 2008 National Ambient Air Quality Standards for Ozone.
Sections 182(b)(2) and 182(f) of the Clean Air Act require
jurisdictions that are classified as “moderate” or higher
nonattainment to implement reasonably available control
technology (RACT) for all categories of volatile organic
compound (VOC) sources covered by a Control Technique
Guideline document as well as for all major stationary sources
of NOX and VOCs that are located within the nonattainment
area. EPA defines RACT as “the lowest emission limitation
that a particular source is capable of meeting by the
application of control technology that is reasonably available
considering technological and economic feasibility.”
In November 2016, Rules 323 and 324 were revised to
implement RACT for sources of NOX. The revised rules were
submitted to the EPA in June of 2017, as part of the SIP
Revision for the Maricopa County Air Quality Department
(MCAQD) Ozone Rules contained in the Arizona SIP. The
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EPA reviewed Rules 323 and 324, and provided the MCAQD
with written rule approvability and rule improvement
comments for the rules. EPA staff informed MCAQD staff
they would be using a conditional approval process to act on
Rules 323 and 324, and the MCAQD would need to draft a
commitment letter outlining revisions to Rules 323 and 324
to address the rule approvability comments.
On January 28, 2019, the MCAQD submitted a Letter of
Commitment for Conditional Approval of the Maricopa
County RACT SIP to the EPA. Later, on December 5, 2019,
the MCAQD submitted a supplemental commitment letter
for Rule 324 to address additional rule approvability
comments MCAQD received after the original commitment
letter was submitted. Based on the commitment letters, the
EPA published a proposed conditional approval of Rules 323
and 324 in the Federal Register on December 30, 2019. The
proposed conditional approval outlined EPA’s official rule
approvability comments (“rule deficiencies”) which precluded
full approval of the rules into the Arizona SIP.
EPA’s final conditional approval was published on July 20,
2020. The effective date of the final rule was August 19, 2020.
If the MCAQD, through the ADEQ, submits the rule
revisions that the MCAQD has committed to submit within
12 months of the effective date of the final rule and the EPA
approves the submission, then the identified deficiencies will
be cured, and the rules will be approved as part of the
Arizona SIP.
A description of each rule, the specific deficiencies associated
with each rule, the MCAQD’s proposed revisions to address
the deficiencies for each rule, and the draft rules with
strikethrough-underline are included in the two attached draft
Notices of Final Rulemaking.
Support/Opposition: During the rulemaking process, the MCAQD has received
written feedback from four (4) stakeholders. The stakeholders
did not express support nor opposition to the rulemaking.
Staff
Recommendation: Approve
Board of Health
Recommendation: Approve
Additional Comments: This rulemaking is following procedures identified in state
statutes and the Maricopa County Enhanced Regulatory
Outreach Program (EROP) Policy. The County Manager
briefed the Board of Supervisors regarding the rulemaking in
December 2017. The Board of Health Meeting to initiate
regulatory change for Rules 323 and 324 occurred on
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February 25, 2019. Stakeholder workshops for Rule 323 were
held on August 22, 2018 and September 23, 2020, and for
Rule 324 were held on August 22, 2018 and October 24,
2019. Notices of Proposed Rulemaking for the two rules were
posted on the EROP website on November 24, 2020. On
April 26, 2021, the Board of Health made a recommendation
to the Board of Supervisors to approve the revisions to Rules
323 and 324.
A newspaper notice of the Board of Supervisors public
hearing will be published in the Arizona Business Gazette on
May 20, 2021 and May 27, 2021. This regulatory change will
take effect immediately upon approval by the Board of
Supervisors.
Presented By: Philip A. McNeely, R.G., Director
Prepared By: Planning and Analysis Division
Attachments: Preamble required by Arizona Revised Statutes (A.R.S.) § 49-
471.07 (See the Draft Notice of Final Rulemaking)
Rule 323
Rule 324
Summary of the proposed regulatory change (See Item 4 of
the Draft Notice of Final Rulemaking)
Rule 323
Rule 324
Analysis of input received during the process and how that
input was responded to (See Item 9 of the Draft Notice of
Final Rulemaking)
Rule 323
Rule 324
Language of proposed regulatory change or amendment (See
the Draft Notice of Final Rulemaking)
Rule 323
Strikethrough-underline Version
Clean Version
Rule 324
Strikethrough-underline Version
Clean Version
Minutes from Board of Health meetings
Copies of all written and electronic Stakeholder input
EPA Region IX Air Division Technical Support Documents
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Return to list of attachments
DRAFT NOTICE OF FINAL RULEMAKING
MARICOPA COUNTY AIR POLLUTION CONTROL REGULATIONS
REGULATION III – CONTROL OF AIR CONTAMINANTS
RULE 323: FUEL BURNING EQUIPMENT FROM
INDUSTRIAL/COMMERCIAL/INSTITUTIONAL (ICI) SOURCES
The Maricopa County Air Quality Department (MCAQD) is proposing to amend Rule 323 (Fuel
Burning Equipment from Industrial/Commercial/Institutional (ICI) Sources). The Control Officer
is posting this Draft Notice of Final Rulemaking on the Maricopa County Enhanced Regulatory
Outreach Program (EROP) website as part of the Report to the Board of Supervisors, in accordance
with the Maricopa County EROP Policy. This notice includes the preamble, as prescribed in A.R.S.
§ 49-471.05, and the full text of the rule, including the intended actions to make new sections or
amend, repeal, or renumber the sections of the rule. This notice also includes a list of all previous
notices posted on the Maricopa County EROP website addressing the proposed rule and the
concise explanatory statement prescribed in A.R.S. § 49-471.07, subsection B.
PREAMBLE
1. Statutory authority for the rulemaking:
A.R.S. §§ 49-112, 49-474, 49-479 and 49-480
2. Name and address of department personnel with whom persons may communicate
regarding the rulemaking:
Name: Scott Kahldon or Kimberly Butler
Maricopa County Air Quality Department
Planning and Analysis Division
Address: 3800 N Central Avenue, Suite 1400
Phoenix, AZ 85012
Telephone: (602) 506-6010
Fax: (602) 506-6179
Email: AQPlanning@maricopa.gov
Submit Comments At: http://maricopa.gov/FormCenter/Regulatory-Outreach-17/Citizen-
Comments-94
3. Rulemaking process:
This rulemaking (AQ-2017-007-Rule 323) is following procedures identified in state statutes
and the Maricopa County EROP Policy:
County Manager Briefing: December 2017
Stakeholder Workshops: August 22, 2018
September 23, 2020
Board of Health Meeting to Initiate Regulatory Change: February 25, 2019
Notice of Proposed Rulemaking: November 24, 2020
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Return to list of attachments
Board of Health Meeting to Recommend Approval to
the Board of Supervisors: April 26, 2021
Board of Supervisors Formal Meeting to set the Public
Hearing: May 19, 2021
Board of Supervisors Public Hearing: June 23, 2021
4. Explanation of the rule, including the control officer's reasons for initiating the
rulemaking:
Rule 323 (Fuel Burning Equipment from Industrial/Commercial/Institutional (ICI) Sources)
limits emissions of nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), and
particulate matter (PM) from fuel burning equipment at industrial, commercial, and
institutional (ICI) sources. The MCAQD is proposing to revise Rule 323 to address rule
deficiencies identified by the U.S. Environmental Protection Agency (EPA) to secure full
approval of Rule 323 as a revision to the Arizona State Implementation Plan (SIP).
On May 4, 2016, portions of Maricopa County were designated as a moderate nonattainment
area with respect to the 2008 National Ambient Air Quality Standards for Ozone. Sections
182(b)(2) and 182(f) of the Clean Air Act require jurisdictions that are classified as
“moderate” or higher nonattainment to implement reasonably available control technology
(RACT) for all categories of volatile organic compound (VOC) sources covered by a Control
Technique Guideline document as well as for all major stationary sources of NOX and VOCs
that are located within the nonattainment area. EPA defines RACT as “the lowest emission
limitation that a particular source is capable of meeting by the application of control
technology that is reasonably available considering technological and economic feasibility.”
The EPA provides guidance on RACT for sources of NOX through Alternative Control
Technology (ACT) documents which offer State and local air pollution control authorities
information that assists in determining NOX-RACT for air quality rules. In addition, the
EPA reviews SIP-approved air quality rules from other air districts with ozone
nonattainment areas to assist in determining NOX-RACT for air quality rules.
In November 2016, Rule 323 was revised to implement RACT for sources of NOX. The
revised rule was submitted to the EPA in June of 2017, as part of the SIP Revision for the
Maricopa County Air Quality Department Ozone Rules contained in the Arizona SIP. The
EPA reviewed Rule 323 and provided the MCAQD with written rule approvability and rule
improvement comments for the rule. EPA staff informed MCAQD staff they would be
using a conditional approval process to act on Rule 323 and the MCAQD would need to
draft a commitment letter outlining revisions to Rule 323 to address the rule approvability
comments.
On January 28, 2019, the MCAQD submitted a Letter of Commitment for Conditional
Approval of the Maricopa County RACT SIP to the EPA. Based on the commitment letter,
the EPA published a proposed conditional approval of Rule 323 in the Federal Register on
December 30, 2019 (Docket ID; EPA-R09-OAR-2019-0321). The proposed conditional
approval rulemaking was available for a 30-day comment period, but no comments were
received. The proposed conditional approval references a Technical Support Document
(TSD) which includes a thorough review of Rule 323 and MCAQD’s commitments. The
TSD outlines EPA’s eight (8) official rule approvability comments (“rule deficiencies”)
which preclude full approval of the rule into the SIP as well as one (1) rule revision
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recommendation, which is not currently the basis for rule disapproval but is recommended
for this current proposed rulemaking for Rule 323. Revisions addressing both the EPA’s
identified deficiencies and recommendation have been made to the proposed draft Rule 323
(included in this notice). A link to EPA’s TSD is located under Section 5 of this notice.
EPA’s final conditional approval was published on July 20, 2020. The effective date of the
final rule was August 19, 2020. If the MCAQD, through the ADEQ, submits the rule
revisions that the MCAQD has committed to submit within 12 months and the EPA
approves the submission, then the identified deficiencies will be cured, and the rule will be
approved as part of the Arizona SIP.
Details about the EPA’s identified deficiencies and the MCAQD’s proposed remedies are
described below, followed by the EPA rule recommendation and the MCAQD’s proposed
revision to address the recommendation.
Deficiency 1:
The emergency fuel use exemptions in Section 104 are overly broad. To correct this, the
MCAQD should clarify in this section that emergency fuel is only allowed under natural gas
curtailments or natural gas emergencies. The MCAQD should further limit the total
allowable length of emergency fuel burning to be consistent with other jurisdictions (see,
Imperial County APCD Rule 400.1 Section D.3) Also, Rule 323 does not require that the
facility owner/operator notify the MCAQD when switching to emergency fuel, which Rule
322 “Power Plant Operations” (which regulates similar types of combustion equipment)
does. This is an enforceability issue. Finally, the language in section 104 exempting units
firing emergency for testing purposes could be interpreted to allow for the exemption during
any operating period so long as the there was a testing period. The MCAQD should clarify
that the exemptions only apply during the testing period.
Remedy 1:
The MCAQD is proposing to clarify the exemptions for emergency fuel use only apply
during natural gas curtailments and natural gas emergencies and for up to 36 cumulative
hours per year for testing, reliability, training, and maintenance purposes. The MCAQD is
proposing to add a requirement for the owner or operator to notify the MCAQD when
switching to emergency fuel. Also, the MCAQD is proposing to limit the total allowable
length of emergency fuel combustion during natural gas curtailments and natural gas
emergencies to 168 hours per year per combustion unit (for combustion units located at a
major stationary source of nitrogen oxides).
Deficiency 2:
All major sources of NOx must be subject to RACT limits or requirements. All turbines, and
all boilers rated larger than 100 MMBtu/hr must comply with the limits in section 304.
Boiler units rated between 10 MMBtu/hr and 100 MMBtu/hr may opt to comply with the
limits in section 304, or tune the units annually as required in section 304.1. The burner
maintenance requirements in section 304.1 are not RACT, as other jurisdictions regulating
units in this size category are able to achieve numeric limits (down to 5 MMBtu/hr in
Imperial County APCD Rule 400.2) or have more stringent tuning requirements (as seen in
Ventura County APCD Rule 74.15.1 and South Coast AQMD Rule 1146, Attachment A).
As the rule is written, major source units in the nonattainment area are only required to tune
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the engine instead of complying with a RACT NOx limit. MCAQD must clarify that larger
units (e.g. annual heat input rating of 50 MMBtu/hr or greater, and annual heat input of
220,000 therms or greater) shall comply with Rule 323 by meeting a NOx limit (as seen in
San Diego County APCD Rule 69.2).
Remedy 2:
The MCAQD is proposing to extend the NOX emission limits to units greater than 50
MMBtu/hr for combustion units located at major sources of NOx. The MCAQD is also
proposing to require combustion units rated greater than 10 MMBtu/hour and less than or
equal to 50 MMBtu/hr with annual heat input greater than or equal to 220,000 therms to
comply with the RACT emission limits or RACT tuning procedures for combustion units
located at major sources of NOx.
Deficiency 3:
The NOx limits of 42 ppmv for gas fuel-fired operations and 65 ppmv for liquid fuel-fired
operations for non-turbine combustion equipment in this rule are not consistent with other
jurisdictions limits and are not RACT. Limits in other ozone nonattainment jurisdictions,
such as Imperial County APCD Rule 400.2 and Sacramento Metropolitan AQMD, are set 30
ppmv and 40 ppmv for gas and liquid fuel-fired operations.
Remedy 3:
The MCAQD is proposing to add NOx emission limits for non-turbine combustion
equipment of 30 ppmvdc when burning gaseous fossil fuel and 40 ppmvdc when burning
liquid fossil fuel to meet RACT.
Deficiency 4:
Section 306 states that operators may comply with the limits in this rule by installing an ECS,
and notes that such systems must be properly operated and maintained in accordance with
an approved operations and maintenance plan. The rule language in section 306 could be
interpreted to mean that the installation of an ECS on its own would allow compliance with
the emission limits. However, an ECS that does not sufficiently reduce emissions could meet
section 306’s requirement without any verification for meeting the other section 300
requirements. The effectiveness of such a system in meeting the applicable emission
standards is unknown without a compliance determination requirement (which in section
503 only applies to sections 301-304, and only for units larger than 100 million Btu/hr).
MCAQD must include language that states that an ECS or combustion control system must
also be source tested to confirm compliance with the limit or create parametric monitoring
requirements to put in the operation and maintenance plan. Alternatively, the rule language
in section 306 should be clarified to not allow for the installation of an ECS to be an
alternative to compliance with the RACT limits in sections 301-304.
Remedy 4:
The MCAQD is proposing to revise Section 503.2 to require performance testing for any
unit that is subject to numeric emission limits in Section 301, 304 and/or 305. In addition,
MCAQD is proposing to add Section 307.2.d which will require an O&M plan to contain
12

operating parameters to ensure the owner or operator continues to operate the ECS in the
manner it was operated during the performance test.
Deficiency 5:
The operations and maintenance plan requirements are only approved by the Control
Officer in section 306.3. This constitutes unacceptable director’s discretion. In addition, the
rule allows the facility operator to change the operation and maintenance plan in section
306.3.d by submitting changes. MCAQD must revise this language to resolve these
enforceability questions, either by removing this discretion, including the EPA in approval of
these plans, or outlining clear criteria that must be met for approval. The operation and
maintenance plan must include the control equipment manufacturer’s operation and
maintenance guidelines. If the MCAQD chooses to revise section 306 so that installation of
an emission control system does not result in automatic compliance with the emission limits
in sections 301-304, then this discretion may be acceptable as a source test would be the
primary determinant of compliance with RACT requirements.
Remedy 5:
The MCAQD is proposing to add Section 307.2 which outlines clear criteria that must be
included in an O&M plan for approval by the Control Officer and also states that the O&M
Plan must include the manufacturer’s recommended maintenance procedures and
frequencies. In addition, MCAQD is proposing to revise Section 503 to require performance
tests for any units that are subject to a numeric emission limit.
Deficiency 6:
Section 503.2 specifies that boilers larger than 100 MMBtu/hr must source test triennially
but does not describe a testing frequency for other units. Other units must be tested at least
triennially. MCAQD must also cite the appropriate test method from the list in section 500.
Remedy 6:
The MCAQD is proposing to revise Section 503.2 to require any combustion unit that is
subject to numeric emission limits in Section 301, 304 and/or 305 to conduct performance
tests in accordance with Rule 270 at least once every 5 years. In addition, MCAQD is
proposing to add citations of the appropriate test methods in sections 503.2.a and 503.2.b.
Deficiency 7:
Section 200 of this rule and Maricopa’s Rule 100 General Provisions and Definitions does
not include a definition for “boiler,” which is used throughout this rule, and in the context
of definitions for “annual capacity factor,” “steam generating unit,” and others. For
purposes of enforceability, such a definition is necessary.
Remedy 7:
The MCAQD is proposing to add a definition of “boiler”.
Deficiency 8:
13

Section 200 also does not include a definition for “continuous emissions monitoring
system.” For purposes of enforceability, such a definition is necessary.
Remedy 8:
The MCAQD is proposing to add a definition of “continuous emissions monitoring
system”.
Recommendation 1:
Section 219 defines “steady state” This is defined as a “safe stable megawatt load”, which is
the incorrect measure for non-EGU sources like general ICI sources which may not output
power in megawatts.
Revision 1:
The MCAQD is proposing to remove the definition of “steady state”.
5. Studies relied on in the control officer's evaluation of or justification for the rule and
where the public may obtain or review the studies, all data underlying the studies,
any analysis of the studies and other supporting material.
United States Environmental Protection Agency Region IX Air Division (2019), Technical
Support Document for EPA’s Rulemaking for the Arizona State Implementation Plan
Regarding Rule 323, “Fuel Burning Equipment from Industrial/Commercial/Institutional
(ICI) Sources.”
https://www.regulations.gov/document?D=EPA-R09-OAR-2019-0321-0011
6. An economic, small business and consumer impact statement:
The following discussion addresses each of the elements required for an economic, small
business and consumer impact statement, as prescribed by A.R.S. §§ 41-1055, subsections A,
B and C, and 41-1035:
An identification of the proposed rulemaking, including all of the following:
This rulemaking is proposing to revise Rule 323.
(a) The conduct and its frequency of occurrence that the rule is designed to change.
The MCAQD is proposing to revise Rule 323 to remedy deficiencies identified by the
EPA. This rulemaking is required to secure approval of Rule 323 into the Arizona SIP.
The revisions are explained in more detail in Item #4 of this notice.
(b) The harm resulting from the conduct the rule is designed to change and the
likelihood it will continue to occur if the rule is not changed.
The MCAQD is proposing to revise Rule 323 to remedy deficiencies identified by the
EPA. This rulemaking is required to secure approval of Rule 323 into the Arizona SIP
and avoid sanctions and imposition of a Federal Implementation Plan (FIP) under the
Clean Air Act.
(c) The estimated change in frequency of the targeted conduct expected from the
rule change.
14

The MCAQD is proposing to revise Rule 323 to remedy deficiencies identified by the
EPA. This rulemaking is required to secure approval of Rule 323 into the Arizona SIP.
As with other rules, the MCAQD will use education, outreach, and other compliance
assurance tools to increase the number of people in compliance with the revised rule.
The MCAQD strives to achieve the highest possible compliance rates.
A brief summary of the information included in the economic, small business and
consumer impact statement.
The economic, small business and consumer impact statement addresses each of the
elements required for an economic, small business and consumer impact statement, as
prescribed by A.R.S. §§ 41-1055, subsections A, B, and C, and 41-1035.
Name and address of agency employees who may be contacted to submit or request
additional data on the information included in the economic, small business and
consumer impact statement.
Name: Scott Kahldon or Kimberly Butler
Maricopa County Air Quality Department
Planning and Analysis Division
Address: 3800 N Central Avenue, Suite 1400
Phoenix, AZ 85012
Telephone: (602) 506-6010
Fax: (602) 506-6179
Email: AQPlanning@maricopa.gov
Submit Comments At: http://maricopa.gov/FormCenter/Regulatory-Outreach-17/Citizen-
Comments-94
An identification of the persons who will be directly affected by, bear the costs of or
directly benefit from the proposed rulemaking.
This rulemaking will directly affect industrial, commercial, and institutional sources in
Maricopa County with combustion units that meet the applicability thresholds below:
(1) Each boiler or steam generating unit that has a maximum design rated heat input
capacity greater than 10 million (MM) British thermal units per hour (Btu/hr),
(2) Each stationary gas turbine with a heat input at peak load equal to or greater than 10
MMBtu/hr,
(3) Each co-generation steam generating unit with a heat input of greater than 10
MMBtu/hr, and
(4) Each indirect-fired process heater with a heat input greater than 10 MMBtu/hr.
A cost benefit analysis of the following:
(a) The probable costs and benefits to the implementing agency and other agencies
directly affected by the implementation and enforcement of the proposed
rulemaking.
This rulemaking should not impose any new costs on the MCAQD or on any other
agencies affected by the proposed rulemaking.
15

(b) The probable costs and benefits to a political subdivision of this state directly
affected by the implementation and enforcement of the proposed rulemaking.
This rulemaking should not impose any significant new costs on political subdivisions of
this state affected by the proposed rulemaking.
(c) The probable costs and benefits to businesses directly affected by the proposed
rulemaking, including any anticipated effect on the revenues or payroll
expenditures of employers who are subject to the proposed rulemaking.
The MCAQD is proposing to revise Rule 323 to remedy deficiencies identified by the
EPA. This rulemaking is required to secure approval of Rule 323 into the Arizona SIP
for RACT and avoid sanctions and imposition of a FIP under the Clean Air Act. This
rulemaking should not impose any significant new costs on businesses affected by the
proposed rulemaking. The MCAQD anticipates that increased clarity provided by the
Rule 323 revisions will provide a benefit to the regulated community; it will take less time
for sources subject to the rule to understand and comply with the rule, which leads to
increased compliance, and a decrease in costs of compliance to the regulated community.
A general description of the probable impact on private and public employment in
businesses, agencies and political subdivisions of this state directly affected by the
proposed rulemaking.
This rulemaking should have no impact on private or public employment in businesses,
agencies, and political subdivisions of this state.
A statement of the probable impact of the proposed rulemaking on small businesses.
The statement shall include:
(a) An identification of the small businesses subject to the proposed rulemaking.
Small businesses subject to this rulemaking are industrial, commercial, and institutional
sources in Maricopa County that have fuel burning equipment that meet the
requirements of Section 102 of the draft rule included in this notice.
(b) The administrative and other costs required for compliance with the proposed
rulemaking.
The MCAQD is proposing to revise Rule 323 to remedy deficiencies identified by the
EPA. This rulemaking is required to secure approval of Rule 323 into the Arizona SIP
for RACT and avoid sanctions and imposition of a FIP under the Clean Air Act.
The MCAQD does not anticipate the rule revisions will impose any significant new costs
on small businesses subject to the proposed rule.
(c) A description of the methods that the agency may use to reduce the impact on
small businesses.
i. Establish less stringent compliance or reporting requirements in the rule for
small businesses.
This rulemaking does not impose any significant new compliance requirements on
small businesses and does not establish any significant new reporting requirements
for small businesses.
16

ii. Establish less stringent schedules or deadlines in the rule for compliance or
reporting requirements for small businesses.
This rulemaking does not impose any significant new compliance requirements on
small businesses and does not establish any significant new reporting requirements
for small businesses.
iii. Consolidate or simplify the rule's compliance or reporting requirements for
small businesses.
This rulemaking does not impose any significant new compliance requirements on
small businesses and does not establish any significant new reporting requirements
for small businesses.
iv. Establish performance standards for small businesses to replace design or
operational standards in the rule.
This rulemaking is unlikely to impose any new design or operational requirements on
small businesses.
v. Exempt small businesses from any or all requirements of the rule.
This rulemaking does not impose any significant new requirements on small
businesses.
(d) The probable cost and benefit to private persons and consumers who are directly
affected by the proposed rulemaking.
This rulemaking should not result in any significant costs for private persons and
consumers.
A statement of the probable effect on state revenues.
The rulemaking will not impose increased monetary or regulatory costs on other state
agencies, political subdivisions of this state, persons, or individuals so regulated. Without
costs to pass through to customers, there is no projected change in consumer purchase
patterns and, thus, no impact on state revenues from sales taxes.
A description of any less intrusive or less costly alternative methods of achieving the
purpose of the proposed rulemaking, including the monetizing of the costs and
benefits for each option and providing the rationale for not using nonelected
alternatives.
The purpose of this rulemaking is to revise Rule 323 to remedy deficiencies identified by the
EPA. This rule making is required to secure approval of Rule 323 into the State
Implementation Plan (SIP) for RACT and avoid sanctions and imposition of a Federal
Implementation Plan (FIP) under the Clean Air Act.
A description of any data on which a rule is based with a detailed explanation of how
the data was obtained and why the data is acceptable data.
Not applicable.
7. The proposed effective date of the rule:
The proposed effective date of this rulemaking is June 23, 2021.
17

8. Such other matters as are prescribed by statute and that are applicable to the county
or to any specific rule or class of rules:
Under A.R.S. § 49-479(C), a county may not adopt a rule or ordinance that is more stringent
than the rules adopted by the Director of the Arizona Department of Environmental Quality
(ADEQ) for similar sources unless it demonstrates compliance with the applicable
requirements of A.R.S. §49-112.
§ 49-112 County regulation; standards
§ 49-112(A)
When authorized by law, a county may adopt a rule, ordinance or regulation that is more
stringent than or in addition to a provision of this title or rule adopted by the director or any
board or commission authorized to adopt rules pursuant to this title if all of the following
requirements are met:
1. The rule, ordinance or regulation is necessary to address a peculiar local condition.
2. There is credible evidence that the rule, ordinance or regulation is either;
(a) Necessary to prevent a significant threat to public health or the environment that
results from a peculiar local condition and is technically and economically feasible.
(b) Required under a federal statute or regulation or authorized pursuant to an
intergovernmental agreement with the federal government to enforce federal statutes
or regulations if the county rule, ordinance or regulation is equivalent to federal
statutes or regulation.
3. Any fee or tax adopted under the rule, ordinance or regulation does not exceed the
reasonable costs of the county to issue and administer the permit or plan approval
program.
§ 49-112(B)
When authorized by law, a county may adopt rules, ordinances or regulations in lieu of a
state program that are as stringent as a provision of this title or rule adopted by the director
or any board or commission authorized to adopt rules pursuant to this title if the county
demonstrates that the cost of obtaining permits or other approvals from the county will
approximately equal or be less than the fee or cost of obtaining similar permits or approvals
under this title or any rule adopted pursuant to this title. If the state has not adopted a fee or
tax for similar permits or approvals, the county may adopt a fee when authorized by law in
the rule, ordinance or regulation that does not exceed the reasonable costs of the county to
issue and administer that permit or plan approval program.
The MCAQD is in compliance with A.R.S. §§ 49-112 (A) and (B). Rule 323 meets A.R.S. §
49-112 (A) (1) by demonstrating that the rule is necessary to address a peculiar local
condition, in that Maricopa County fails to meet the 8-hour NAAQS for ozone. Rule 323
meets the requirements of A.R.S. § 49-112 (A) (2) (b), in that Maricopa County is required by
federal law to revise existing rules to address RACT for industrial, commercial, and
institutional sources that have fuel burning equipment. As there is no new fee or tax
associated with this proposed rulemaking, the MCAQD also affirms that Rule 323 meets the
requirements of A.R.S. § 49-112 (A) (3) and A.R.S. § 49-112 (B).
18

9. List of all previous notices posted to the Maricopa County EROP website addressing
the proposed rule and a concise explanatory statement, as prescribed by A.R.S. § 49-
471.07, subsection B:
(a) List of all previous notices posted to the Maricopa County EROP website
addressing the proposed rule:
Notice Date of Posting
Briefing Notification to County Manager: January 26, 2018
Notice of Stakeholder Workshop: August 03, 2018
September 09, 2020
Notice of Board of Health Meeting to Initiate February 08, 2019
Regulatory Change:
Notice of Proposed Rulemaking: November 24, 2020
Notice of Board of Health Meeting to Make
Recommendations to the Board of Supervisors: April 12, 2021
(b) The following discussion addresses each of the elements required for a concise
explanatory statement, as prescribed by A.R.S. § 49-471.07, subsection B:
i. A description of any change between the proposed rule or ordinance, the final
rule or ordinance or notice of final supplemental rule or ordinance.
The following changes were made after the Notice of Proposed Rulemaking was
published on November 24, 2020.
1. The MCAQD revised the definition of Parts Per Million By Volume Dry
(PPMVD) to be consistent between Rules 322, 323, and 324. The section was
revised as indicated below:
Section 219: PARTS PER MILLION BY VOLUME DRY(PPMVD): A unit
of proportion used to express concentration that is corrected to a dry basis.
2. Based off of staff comments, the MCAQD removed the oxygen corrections
“corrected to 15% oxygen” and “corrected to 3% oxygen” from the definition of
Parts Per Million By Volume Dry and placed them closer to the corresponding
emission limits to improve rule clarity. Section 304.2 and Section 305 were
revised as indicated below:
Section 304.2: RACT Emission Limits: Limit nitrogen oxide emissions to no
more than the following amounts:
a Stationary Gas Turbines:
(1) 42 ppmvd corrected to 15% oxygen calculated as nitrogen dioxide, when
burning gaseous fuel.
(2) 65 ppmvd corrected to 15% oxygen calculated as nitrogen dioxide, when
burning liquid fuel.
b. All Combustion Units Except Stationary Gas Turbines:
19

(1) 30 ppmvd corrected to 3% oxygen calculated as nitrogen dioxide, when
burning gaseous fuel.
(2) 40 ppmvd corrected to 3% oxygen calculated as nitrogen dioxide, when
burning liquid fuel.
Section 305: LIMITATIONS-CARBON MONOXIDE: An owner or operator
of any combustion unit with a heat input greater than 100 MMBtu/hr shall not
cause to be discharged into the atmosphere, carbon monoxide (CO), measured in
excess of 400 ppmvd corrected to 15% oxygen for Stationary Gas Turbines, and
corrected to 3% oxygen for all Combustion Units Except Stationary Gas
Turbines.
3. The MCAQD removed the language “in accordance with the requirements of
Rule 270 of these rules” in section 503.2. The section was revised as indicated
below:
Section 503.2: Source Test Requirements: The owner or operator of any
combustion unit that is subject to numeric emission limits in Section 301,
304 and/or 305 of this rule shall conduct performance tests at least once
every 5 years. The result of the performance test shall be the arithmetic mean
of the results of three test runs. Each test run shall have a minimum sample
time of one hour. In addition, the owner or operator shall comply with the
following requirements:
4. Based off of staff comments, the MCAQD added the language “Monthly
records” in section 501.1 and added the language “and amount” in section 501.2
to clarify tracking fuel use and standardizing language between the two sections.
Section 501.1 and Section 501.2 were revised as indicated below:
Section 501.1: Combustion Units: Monthly records of type and amount of
fuel used, and the sulfur content of any liquid fuel or waste derived fuel gas
combusted.
Section 501.2: Emergency Fuel Usage: Monthly records of type and amount
of emergency fuel used, the sulfur content of the fuel, dates and hours of
operation using emergency fuel, and nature of the emergency or purpose for
the use of the emergency fuel as stated in Sections 104.2 and 104.3. Yearly
records of the twelve month log of hours of operation using emergency fuel.
ii. A summary of the comments and arguments for and against the notice and the
county’s response to the comments and arguments.
Return to list of attachments
The following discussion evaluates the arguments for and against the rule and
includes responses to comments received on the proposed rule or the preamble in the
Notice of Proposed Rulemaking. The MCAQD received written comments from two
(2) stakeholders. All of the comments were reviewed and evaluated by the MCAQD.
Comment #1: This rule contains similar requirements for tracking fuel use and
days/hours of operation. I would like to request the same change as stated above (for
R322, section 501.1 - This rule now requires records of the type and amount of fuel
20

used, sulfur content and days and hours of operation. I would like to remove the
requirement to track days and hours of operation and that fuel use be required to be
tracked monthly. Fuel tracking monthly makes the most sense since invoices are
typically sent monthly (in the case of natural gas). I have been unable to identify a
reason to track days and hours of operation. This information does not appear to be
needed to determine compliance).
Response #1: The MCAQD considered your comment and deleted the requirement
for days and hours of operation. In addition, the MCAQD clarified that fuel usage be
tracked monthly.
Comment #2: In Maricopa County’s (the County) workshop presentation, the
County recommends accepting the more stringent boiler tuning requirements and
suggests requirements based rated capacity and whether or not the source was at a
major source. Concerning the County’s recommendations for altering requirements
based on rated capacity of the unit, APS suggests an alternative. APS has reviewed
EPA’s comment and believe EPA was intending to apply RACT to “major source
units” (units emitting 100 tons/yr of NOx) and not a minor source unit at a “major
source” as suggested by the County’s proposed commitment. APS requests that
RACT requirements only apply to major source units. Applying a major source
applicability limit would be consistent with EPA’s recommendation with Rule 322.
APS owns a Clayton Boiler rated at 11 MBtu/hr, which emits approximately 25 lbs
per year. APS has reviewed the examples for boiler tuning requirements and find
them excessive in some situations for simple and small units. Multiple items in the
referenced boiler tuning requirements could not work for this unit. APS doesn't
support more stringent requirements for the smaller units. At a minimum, there
should be language that accommodate the size and design of the unit.
Response #2: The MCAQD considered your comment and developed a table that
clearly outlines which combustion units at a major source of NOx must comply with
RACT requirements, see Table 323-1 in the draft rule. Some smaller combustion
units, units greater than 10 MMBtu/hour and less than or equal to 50 MMBtu/hour
with annual heat input less than 220,000 therms, will not have to comply with RACT
requirements.
Return to list of attachments
EXACT WORDING OF THE RULE
MARICOPA COUNTY
AIR POLLUTION CONTROL REGULATIONS
REGULATION III – CONTROL OF AIR CONTAMINANTS
RULE 323
FUEL BURNING EQUIPMENT FROM
INDUSTRIAL/COMMERCIAL/INSTITUTIONAL (ICI) SOURCES
INDEX
SECTION 100 – GENERAL
21

101 PURPOSE
102 APPLICABILITY
103 EXEMPTIONS
104 PARTIAL EXEMPTIONS
SECTION 200 – DEFINITIONS
201 ALTERNATIVE FUELS
202 ANNUAL HEAT INPUT
203 BOILER
202 204 COGENERATION STEAM GENERATING UNIT
205 COMBUSTION CONTROL SYSTEM
206 COMBUSTION UNIT
207 CONTINUOUS EMISSIONS MONITORING SYSTEM (CEMS)
203 208 CORRECTIVE ACTION PLAN (CAP)
204 DISTILLATE OIL
205 209 EMERGENCY FUEL
206 210 EMISSION CONTROL SYSTEM (ECS)
207 211 FOSSIL FUEL
212 GAS TURBINE
208 213 HEAT INPUT
214 LOW SULFUR OIL
209 215 NATURAL GAS CURTAILMENT
210 216 OPACITY
217 OPERATING HOUR
211 218 PARTICULATE MATTER EMISSIONS
219 PARTS PER MILLION BY VOLUME DRY (PPMVD)
212 220 PEAK LOAD
213 221 PROCESS HEATER
214 222 RATED HEAT INPUT CAPACITY
215 REGENERATIVE CYCLE GAS TURBINE
216 RESIDUAL OIL
217 SIMPLE CYCLE GAS TURBINE
218 223 STATIONARY GAS TURBINE
219 STEADY STATE
22

220 224 STEAM GENERATING UNIT
221 225 SULFUR OXIDES (SOX)
222 226 ULTRA LOW SULFUR OILDIESEL
223 227 UNCOMBINED WATER
224 228 WASTE DERIVED FUEL GAS
225 229 WATER HEATER
SECTION 300 – STANDARDS
301 LIMITATIONS - PARTICULATE MATTER
302 LIMITATIONS - OPACITY
303 LIMITATIONS - SULFUR IN FUEL
304 LIMITATIONS - NITROGEN OXIDES
305 LIMITATIONS - CARBON MONOXIDE
306 GOOD COMBUSTION PRACTICES FOR STATIONARY GAS TURBINES
306 307 REQUIREMENTS FOR AIR POLLUTION CONTROL EQUIPMENT ECS
AND ECS MONITORING EQUIPMENT
308 EMERGENCY FUEL USE NOTIFICATION
SECTION 400 – ADMINISTRATIVE REQUIREMENTS
401 COMPLIANCE SCHEDULE FOR PERFORMANCE TESTING
402 COMPLIANCE SCHEDULE FOR RACT TUNING PROCEDURE
SECTION 500 – MONITORING AND RECORDS
501 RECORDKEEPING AND REPORTING
502 RECORDS RETENTION
503 COMPLIANCE DETERMINATION DEMONSTRATION
504 COMPLIANCE DETERMINATION-TEST METHODS INCORPORATED BY
REFERENCE
APPENDIX A TO RULE 323
23

Adopted 07/02/2003; Revised 10/17/2007; Revised 11/02/2016; Revised MM/DD/YYYY
MARICOPA COUNTY
AIR POLLUTION CONTROL REGULATIONS
REGULATION III-CONTROL OF AIR CONTAMINANTS
RULE 323
FUEL BURNING EQUIPMENT FROM INDUSTRIAL/COMMERCIAL/INSTITUTIONAL (ICI)
SOURCES
SECTION 100 – GENERAL
101 PURPOSE: To limit the discharge of nitrogen oxides, sulfur oxides, carbon monoxide, and
particulate matter emissions into the atmosphere from fuel burning combustion equipment
units at industrial and/or commercial and/or institutional (ICI) sources.
102 APPLICABILITY: This rule applies to the following types of ICI combustion equipment
units that burns burn either fossil fuels or alternative fuels:
102.1 Each boiler or steam generating unit that has a maximum design rated heat input
capacity from fuels combusted in the generating unit of greater than 10 million (MM)
British thermal units per hour (Btu/hr)(2.9 Megawatts (MW)).
102.2 Each stationary gas turbine with a heat input at peak load equal to or greater than 2.9
megawatts (MW) 10 MMBtu/hr.
102.3 Each cogeneration steam generating unit with a heat input of greater than 10
MMBtu/hr.
102.4 Each indirect-fired process heater with a heat input greater than 10 MMBtu/hr.
102.5 NSPS & NESHAP: In addition to this rule, facilities may be subject to New Source
Performance Standards (NSPS) in Rule 360 and/or National Emission Standards for
Hazardous Air Pollutants (NESHAP) in Rule 370 of these rules.
103 EXEMPTIONS: This rule shall not apply to the following types of equipment:
103.1 Incinerators, crematories, or burn-off ovens; or
103.2 Dryers, cement and lime kilns; or
103.3 Direct-fired process heaters; or
103.4 Medical waste incinerators; or
103.5 Reciprocating internal combustion equipment engines; or
103.6 Combustion equipment used in power plant operations for the purpose of supplying
greater than one third of the electricity to any utility power distribution system for
sale; or
103.7 Combustion equipment associated with nuclear power plant operations; or
103.8 Water heaters used for the sole purpose of heating hot water for comfort or for
radiant heat; or
24

103.9 Municipal solid waste landfill enclosed combustors and non-enclosed flares.
104 PARTIAL EXEMPTIONS:
104.1 Stationary gas turbines listed in Section 102.2 of this rule that are used for any of the
following reasons shall be exempt from Sections 301.1, 301.2, 301, 304, and 305,
501.1, and 501.3 of this rule:
a. Used for firefighting; or
b. Used for flood control; or
c. Engaged by manufacturers in research and the development of equipment for
either gas turbine emission control techniques or gas turbine efficiency
improvements; or.
d. Fired with emergency fuel that is normally fired with natural gas, or
e. Fired with emergency fuel for 36 cumulative hours per year or less, per unit for
testing, reliability, training, and maintenance purposes as allowed by a permit
issued by the Control Officer for that source.
104.2 All steam generating units including cogeneration units and process heaters All
combustion units that are normally fired with natural gas that are used for any of the
following reasons as allowed by a permit issued by the Control Officer shall be
exempt from Sections 301, 304, 305, and 501.1 and 501.3 of this rule: while firing
emergency fuel during a natural gas curtailment or a natural gas emergency. For
combustion units located at a major stationary source of nitrogen oxides, this
exemption shall not exceed 168 hours per calendar year per combustion unit,
excluding hours of operation for testing, reliability, training, and maintenance.
a. Fired with an emergency fuel that is normally fired with natural gas; or
b. Firing any emergency fuel for testing, reliability, and maintenance purposes for
36 cumulative hours per year, per unit or less.
104.3 All combustion units that are normally fired with natural gas shall be exempt from
Sections 301, 304, 305, and 501.1 of this rule while firing emergency fuel for the
purposes of testing, reliability, training, and maintenance. This exemption shall not
exceed 36 hours per calendar year per combustion unit, excluding hours of operation
during natural gas curtailments and natural gas emergencies.
SECTION 200 – DEFINITIONS: For the purpose of this rule, the following definitions shall
apply, in addition to those definitions found in Rule 100 (General Provisions and Definitions) of these
rules. In the event of any inconsistency between any of the Maricopa County air pollution control
rules, the definitions in this rule take precedence.
201 ALTERNATIVE FUELS: Substitutes for traditional oil-derived and fossil-fuel derived
motor vehicle fuels including but not limited to biodiesel, propane, ethanol, or methanol, or
waste derived fuel gas.
202 ANNUAL HEAT INPUT: The actual total heat input of fuels combusted in a unit during
a calendar year, as calculated based on the amount of each fuel combusted and the higher
heating value of each fuel. Annual heat input shall not include the heat input from
25

emergency fuel combusted during natural gas curtailments and natural gas emergencies or
emergency fuel combusted for purposes of testing, reliability, training, and maintenance as
long as the usage limits in Sections 104.2 and 104.3 are not exceeded.
203 BOILER: A device that combusts any fossil fuel or alternative fuel and recovers thermal
energy to heat water or another material.
202 204 COGENERATION STEAM GENERATING UNIT: A steam or hot water generating
unit Any device that is fired with fossil fuels or alternative fuels and simultaneously produces
both useful thermal energy (such as heat or steam) and either electrical (or mechanical
energy) and thermal energy (such as heat or steam) from the same primary energy source.
205 COMBUSTION CONTROL SYSTEM: Equipment or technology, such as water
injection or low-NOX burners, that reduce the formation of nitrogen oxides during
combustion of fossil fuels or alternative fuels.
206 COMBUSTION UNIT: Any boiler, steam generating unit, stationary gas turbine,
cogeneration steam generating unit, or indirect-fired process heater listed in Section 102 of
this rule.
207 CONTINUOUS EMISSIONS MONITORING SYSTEM (CEMS): The total
equipment required to sample, analyze, measure, and provide a permanent record of
emissions by means of readings recorded at least once every 15 minutes (using an automated
data acquisition and handling system (DAHS)).
203 208 CORRECTIVE ACTION PLAN (CAP): A methodical procedure that is used to evaluate
and correct a turbine operational problem and that includes, at a minimum, improved
preventative maintenance procedures, improved ECS operating practices, possible
operational amendments, and progress reports.
204 DISTILLATE OIL: A petroleum fraction of fuel oil produced by distillation that complies
with the specifications for fuel oil numbers 1 or 2, as defined by the American Society for
Testing and Materials in ASTM D396-01, “Standard Specification for Fuel Oils.”
205 209 EMERGENCY FUEL: Fuel fired by a gas combustion unit, normally fueled by natural
gas, only during circumstances of unforeseen disruption or interruption in the supply of
natural gas to a unit that normally runs on natural gas. The inability to burn natural gas may
be one of the following, but is not limited to, natural gas emergency, natural gas curtailment,
or a breakdown of the delivery system. Fuel fired only for purposes of testing, reliability,
training, and maintenance or during circumstances such as a natural gas emergency or a
natural gas curtailment, or breakdown of delivery system such as an unavoidable interruption
of supply that makes it impossible to fire natural gas in the combustion unit. Fuel is not
considered emergency fuel if it is used to avoid either peak demand charges or high gas
prices during on-peak price periods or due to a voluntary reduction in natural gas usage.
206 210 EMISSION CONTROL SYSTEM (ECS): A system approved in writing by the Control
Officer, designed and operated in accordance with good engineering practice to reduce
emissions. Post-combustion systems that are approved in writing by the Control Officer and
are designed and operated in accordance with good engineering practice to reduce emissions
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from combustion equipment. A combustion control system is not an emission control
system.
207 211 FOSSIL FUEL: Naturally occurring carbonaceous substances from the ground such as
natural gas, petroleum, coal, and any form of solid, liquid or gaseous fuel derived from such
material for the purpose of creating energy.
212 GAS TURBINE: A rotary engine driven by the expansion of hot gases that are generated
by the combustion of fuel.
208 213 HEAT INPUT: Heat derived from the combustion of fuel not including the heat input
from preheated combustion air, recirculated flue gases, or exhaust gases from other sources,
such as gas turbines, internal combustion engines, and kilns.
214 LOW SULFUR OIL: Fuel oil containing less than or equal to 0.05% sulfur by weight.
209 215 NATURAL GAS CURTAILMENT: A shortage in the supply of natural gas, due solely to
limitations or restrictions in distribution pipelines by the utility supplying the gas and not due
to the cost of natural gas.
210 216 OPACITY: A condition of the ambient air, or any part thereof, in which an air contaminant
partially or wholly obscures the view of an observer.
217 OPERATING HOUR: A clock hour during which a unit combusts fuel, either for part of
the hour or for the entire hour.
211 218 PARTICULATE MATTER EMISSIONS: Any and all particulate matter emitted to the
ambient air as measured by applicable state and federal test methods.
219 PARTS PER MILLION BY VOLUME DRY (PPMVD): A unit of proportion used to
express concentration that is corrected to a dry basis.
212 220 PEAK LOAD: 100% of the manufacturer’s design capacity of a gas turbine at 288° Kelvin,
60% relative humidity, and 101.3 kilopascals pressure (ISO 3977 standard day reference
conditions and ratings).
213 221 PROCESS HEATER: An enclosed combustion device that uses controlled flame to
transfer heat to a process fluid or a process material that is not a fluid or to heat transfer
material for use in a process unit (not including the generation of steam). A process heater
may be either indirect or direct-fired, dependent upon whether the gases of combustion mix
with and exhaust to the same stack or vent (direct-fired) with gases emanating from the
process material or not (indirect-fired). Emissions from indirect-fired units consist entirely of
products of combustion while emissions from direct-fired units are unique to the given
process and may vary widely in any industrial process. A process heater is not an oven or
kiln used for drying, curing, baking, cooking, calcining, or vitrifying.
214 222 RATED HEAT INPUT CAPACITY: The heat input capacity in million Btu/hr. as
specified on the nameplate of the combustion unit. If the combustion unit has been altered
or modified so that its maximum heat input is different than the heat input capacity on the
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nameplate (design heat capacity), the maximum heat input shall be considered as the rated
heat input capacity.
215 REGENERATIVE CYCLE GAS TURBINE: Any stationary gas turbine that recovers
thermal energy from the exhaust gases and utilizes the thermal energy to preheat air prior to
entering the combustor unit.
216 RESIDUAL OIL: The heavier oils that remain after the distillate oils and lighter
hydrocarbons are distilled off in refinery operations. This includes crude oil or fuel oil
numbers 1 and 2 that have a nitrogen content greater than 0.05% by weight, and all fuel oil
numbers 4, 5 and 6, as defined by the American Society of Testing and Materials in ASTM
D396-01, “Standard Specifications for Fuel Oils”.
217 SIMPLE CYCLE GAS TURBINE: Any stationary gas turbine that does not recover heat
from the gas turbine exhaust gases to preheat the inlet combustion air to the gas turbine, or
that does not recover heat from the gas turbine exhaust gases to heat water or generate
steam.
218 223 STATIONARY GAS TURBINE: Any simple cycle gas turbine or regenerative gas turbine
that is not self-propelled or that is attached to a foundation.
219 STEADY STATE: A safe, stable megawatt load at which a unit with equipment in normal
operating conditions is capable of being held for an extended period of time, without
creating an unsafe or unstable operating condition.
220 224 STEAM GENERATING UNIT: An external combustion unit or boiler fired by fossil
fuel that is used to generate hot water or steam. The hot water or steam is then used as
energy for driving another process or piece of equipment. A device that combusts any fossil
fuel or alternative fuel and produces steam or heats water or heats any heat transfer medium.
221 225 SULFUR OXIDES (SOX): The sum of the oxides of sulfur emitted from the flue gas from
a combustion unit that are directly dependent upon the amount of sulfur in the fuel used.
222 226 ULTRA LOW SULFUR DIESEL OIL: Fuel oil containing less than or equal to 0.0015 %
sulfur by weight.
223 227 UNCOMBINED WATER: Condensed water containing no more than analytical trace
amounts of other chemical elements or compounds.
224 228 WASTE DERIVED FUEL GAS: A gaseous fuel that is generated from the biodegradation
of solid or liquid waste including, but not limited to, digester gas and landfill gas.
225 229 WATER HEATER: A closed vessel in which water is heated by combustion of fuel and
water is either withdrawn for use external to the vessel (at pressures not exceeding 160 psi
with all controls and devices preventing water temperatures from exceeding 210°F) or used
for radiant heat. Water heaters are usually no larger than 1 MM Btu/hr as opposed to
boilers, and do not reach temperatures of 220°F and higher that boilers can reach, and are
not manufactured to meet boiler codes.
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SECTION 300 – STANDARDS
301 LIMITATIONS – PARTICULATE MATTER: An owner or operator of any
combustion unit with either a rated heat input capacity or heat input greater than 100
MMBtu/hr shall not discharge, cause, or allow the discharge of particulate matter emissions,
caused by combustion of non-gaseous liquid fuels or a blend of liquid fuels with other fuels,
in excess of 0.10 pounds/MMBtu.
301.1 Limitation-Liquid Fuels: An owner or operator shall not discharge, cause or allow
the discharge of particulate matter emissions, caused by combustion of non-gaseous
liquid fuels or a blend of liquid fuels with other fuels in excess of 0.10 lbs. per
MMBtu, during steady state operations, from any combustion units listed in Sections
102.1, 102.3, and 102.4 of this rule with either a rated heat input capacity or heat
input of greater than 100 MM Btu/hr.
301.2 Particulate Matter Testing: A backhalf analysis shall be performed, using Reference
Method 202 referenced in Section 504.6 of this rule, each time a compliance test for
particulate matter emissions to meet the standards in Section 301.1 of this rule is
performed using Method 5. (The results of the Method 202 testing shall be used for
emissions inventory purposes).
301.3 Good Combustion Practices for Turbines: During steady state operations, an owner
or operator of a stationary gas turbine listed in Section 102.2 of this rule, regardless
of fuel type or size, shall use operational practices recommended by the
manufacturer and parametric monitoring that ensure good combustion control. One
of the following procedures may be used:
a. Monitor the maximum temperature differential across the combustion burners or
at locations around the back end of the turbine, dependent upon the particular
unit, to ensure no more than a 100 F difference using a thermocouple.
Differential temperatures across the burners to demonstrate good combustion
practices shall be measured from at least one minute data point during a
complete steady state operating hour. If a valid maximum temperature
differential of greater than 100F is observed across the burners, investigation
and corrective action shall be taken within three hours to reduce the temperature
difference to 100F or less; or
b. If the manufacturer recommends that the maximum numerical temperature
differential to ensure good combustion is a temperature that is greater than
100°F, then proof of this maximum alternate temperature shall be submitted to
the Control Officer. The procedure to measure the maximum temperature
differential listed above in Section 301.3(a) of this rule shall then be followed
using the alternate recommended maximum temperature differential after
approval by the Control Officer.
c. If a repetitive pattern of failure to meet the proper temperature differential of
100°F or to meet the alternate temperature differential recommended by the
manufacturer indicates that the turbine is not being operated in a manner
consistent with good combustion practices, then the Control Officer may require
the owner or operator to submit a Corrective Action Plan (CAP).
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302 LIMITATIONS – OPACITY: An owner or operator shall not discharge into the ambient
air from any single source of emissions any air contaminant, other than uncombined water,
in excess of 20% opacity.
303 LIMITATIONS – SULFUR IN FUEL: An owner or operator of any applicable
equipment listed in Section 102 of this rule combustion unit that burns liquid fuel oil or a
mixture or blend of fuel oil with any other fuels shall use only ultra low sulfur diesel oil. An
existing supply of low sulfur oil purchased or obtained prior to November 2, 2016 may be
used until depleted. An owner or operator using of any combustion unit that burns waste
derived fuel gas shall use only waste derived fuel gas that contains no more than 0.08%
sulfur by weight, alone or in combination with other fuels.
304 LIMITATIONS – NITROGEN OXIDES: An owner or operator of any combustion
unit shall comply with the subsections specified in Table 323-1.
TABLE 323-1
FOR COMBUSTION UNITS THAT ARE NOT THE OWNER OR
LOCATED AT A MAJOR SOURCE OF OPERATOR SHALL
NITROGEN OXIDES: COMPLY WITH:
Stationary gas turbines 304.1 and 304.2
Combustion units (>100 MMBtu/hr) except stationary gas 304.3
turbines
Combustion units (≤ 100 MMBtu/hr) except stationary gas 304.1 or 304.2 or 304.4*
turbines
FOR COMBUSTION UNITS THAT ARE THE OWNER OR
LOCATED AT A MAJOR SOURCE OF OPERATOR SHALL
NITROGEN OXIDES: COMPLY WITH:
Stationary gas turbines 304.1 and 304.2
Combustion units (> 100 MMBtu/hour) except stationary 304.3
gas turbines
Combustion units (> 50 MMBtu/hour and ≤ 100 304.2
MMBtu/hour) except stationary gas turbines
Combustion units (> 10 MMBtu/hour and ≤ 50 304.2 or 304.4*
MMBtu/hour with annual heat input ≥ 220,000 therms)
except stationary gas turbines
Combustion units (> 10 MMBtu/hour and ≤ 50 304.1 or 304.2 or 304.4*
MMBtu/hour with annual heat input < 220,000 therms)
except stationary gas turbines
* The RACT tuning procedures in Section 304.4 are not appropriate for combustion units equipped with Low-
NOX burners or burners utilizing a premix flame.
304.1 An owner or operator of any combustion equipment listed in Section 102 of this
rule, except gas turbines, with a heat input of greater than 10 MMBtu/hr to 100
MMBtu/hr shall comply either with Sections 304.1(a) or 304.1(b) of this rule. Gas
turbines are subject to both Sections 304.1(a) and 304.1(b) of this rule below:
a. 304.1 Baseline Monitoring and Annual Tuning:
a. Establish and record the initial optimal baseline concentrations for NOX and CO
within 90 days of the first usage of the combustion equipment unit utilizing the
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initial design burner specifications or manufacturer’s recommendations to ensure
good combustion practices. The initial design burner specifications or
manufacturer’s recommendations shall be kept onsite and available to the
Control Office upon request.
b. Tune the combustion unit annually in accordance with good combustion
practices or follow the manufacturer’s recommended procedure, if applicable.
The manufacturer’s recommended procedures shall be kept onsite and available
to the Control Officer upon request. For low emission burner systems that do
not provide accessibility for combustion chamber inspection, burner inspection,
or inspection of the flame pattern, an owner or operator shall provide
documentation from the manufacturer and follow the manufacturer’s
recommended procedure. If using good combustion practices the manufacturer’s
recommended tuning procedure is not available, the owner or operator shall tune
the combustion unit annually include the by following, at a minimum, the steps
listed in 304.1b.(1) – (5), if the combustion unit is so equipped, and if such
procedures are appropriate to the type of combustion unit:
(1) Inspect the burner system and clean and replace any components of the
burner as necessary to minimize emissions of NOX and CO; and
(2) Inspect the burner chamber for areas of impingement and remove if
necessary; and
(3) Inspect the flame pattern and make adjustments as necessary to optimize the
flame pattern; and
(4) Inspect the system controlling the air-to-fuel ratio and ensure that it is
correctly calibrated and functioning properly; and
(5) Measure the NOX and the CO concentration of the effluent stream after each
adjustment was made with a handheld portable monitor to ensure optimal
baseline concentrations are maintained. Using a portable monitor, measure
the NOX and CO concentration of the effluent stream after each adjustment
is made to ensure optimal baseline concentrations are maintained.
b. 304.2 RACT Emission Limits: Limit nitrogen oxide emissions to no more than the
following amounts:
(1) a. Stationary Gas Turbines:
(1) 42 ppmdv ppmvd corrected to 15% oxygen calculated as nitrogen dioxide,
when burning gaseous fuel. During steady state operations, this test result
using EPA Reference Method(s) 7 or other EPA-approved test method
designated by the Control Officer shall be based upon the arithmetic mean
of the results of three test runs. Each test run shall have a minimum sample
run time of one hour.
(2) (2) 65 ppmdv ppmvd corrected to 15% oxygen calculated as nitrogen dioxide,
when burning liquid fuel. During steady state operations, this test result using
EPA Reference Method(s) 7 or other EPA-approved test method designated
by the Control Officer shall be based upon the arithmetic mean of the results
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of three test runs. Each test run shall have a minimum sample run time of
one hour.
b. All Combustion Units Except Stationary Gas Turbines:
(1) 30 ppmvd corrected to 3% oxygen calculated as nitrogen dioxide, when
burning gaseous fuel.
(2) 40 ppmvd corrected to 3% oxygen calculated as nitrogen dioxide, when
burning liquid fuel.
c. For simple gas turbines, the nitrogen oxides shall be measured dry and corrected
to 15% oxygen, during steady state operations. For all other combustion
equipment, the nitrogen oxides shall be measured dry and corrected to 3%
oxygen.
304.2 304.3 Semi-Annual Tuning and RACT Emission Limits: An owner or operator of any
combustion equipment, listed in Section 102 of this rule, with a heat input greater
than 100 MMBtu/hr, shall:
a. Tune the equipment combustion unit every 6 months in accordance with good
combustion practices or a the manufacturer’s recommended procedure that at a
minimum includes the or in accordance with the procedures listed in Section
304.1(a) 304.1.b(1) through (5) of this rule and;
b. Meet the NOX RACT emission limits as stated in Section 304.1(b) 304.2 of this
rule.
304.4 RACT Tuning Procedures: Tune the combustion unit every 12 months using the
procedure in Appendix A of this rule that is appropriate for the combustion unit.
305 LIMITATIONS-CARBON MONOXIDE: An owner or operator of any equipment
listed in Section 102 of this rule combustion unit with a heat input greater than 100
MMBtu/hr shall not cause to be discharged into the atmosphere, carbon monoxide (CO),
measured in excess of 400 ppmv ppmvd corrected to 15% oxygen for Stationary Gas
Turbines, and corrected to 3% oxygen for all Combustion Units Except Stationary Gas
Turbines.at any time. During steady state operations, this test result, using EPA Reference
Method 10 or other EPA-approved test method designated by the Control Officer, shall be
based upon the arithmetic mean of the results of three test runs and shall be measured
during steady state compliance source testing. Each test run shall have a minimum sample
time of one hour. For simple gas turbines, the CO shall be measured dry and corrected to
15% oxygen, during steady state operations. For all other combustion equipment, the CO
shall be measured dry and corrected to 3% oxygen.
306 GOOD COMBUSTION PRACTICES FOR STATIONARY GAS TURBINES: The
owner or operator of any stationary gas turbine listed in Section 102.2 of this rule shall,
regardless of fuel type, use operational practices recommended by the manufacturer to
ensure good combustion control. The owner or operator of any stationary gas turbine listed
in Section 102.2 of this rule shall demonstrate good combustion control using the parametric
monitoring method listed below, or by operating a continuous emissions monitoring system
to demonstrate compliance with the limits in Sections 304 and 305 of this rule, as applicable.
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306.1 Monitor the maximum temperature differential across the combustion burners or at
locations around the back end of the turbine, dependent upon the particular unit, to
ensure no more than a 100F difference using a thermocouple. Differential
temperatures shall be measured and recorded at least once during every operating
hour. If a temperature differential of greater than 100F is observed across the
burners, investigation and corrective action shall be taken within three hours to
reduce the temperature difference to 100F or less.
306.2 If the manufacturer recommends that the maximum numerical temperature
differential to ensure good combustion is greater than 100°F, then proof of this
maximum alternate temperature differential shall be submitted to the Control
Officer. The procedure to measure the maximum temperature differential listed in
Section 306.1 of this rule shall then be followed using this alternate recommended
maximum temperature differential after approval by the Control Officer.
306.3 If the differential temperature exceeds 100°F, or the alternate temperature
differential recommended by the manufacturer and approved by the Control Officer,
during three consecutive operating hours, the operator shall comply with the
recordkeeping requirements in Section 501.3 of this rule. If this occurs more than 3
times in 3 months, the owner or operator shall notify the Control Officer in writing
within 2 business days and the Control Officer shall require the owner or operator to
submit a Corrective Action Plan (CAP).
306 307 REQUIREMENTS FOR AIR POLLUTION CONTROL EQUIPMENT ECS AND
ECS MONITORING EQUIPMENT: If an ECS is operated during a performance test
required by Section 503 of this rule, the owner or operator shall:
306.1 Emission Control System: For affected operations which may exceed any of the
applicable standards set forth in Sections 300 of this rule, an owner or operator may
comply by installing and operating an emission control system (ECS) or a
combustion control system which reduces emissions to below the applicable
standards in Section 300 of this rule.
306.2 307.1 Providing and Maintaining ECS Monitoring Devices: An owner or operator required
to use an approved ECS pursuant to this rule shall not do so without first providing,
properly installing, operating, and maintaining Properly install, operate, and maintain
in calibration and in good working order, devices for indicating temperatures,
pressures, transfer rates, rates of flow, or other operating conditions necessary to
determine if air pollution control equipment is functioning properly and is properly
maintained as described in an approved Operation and Maintenance (O&M) Plan.
306.3 O&M Plan Required for ECS:
a. General Requirements: An owner or operator shall provide and maintain an
O&M Plan for any ECS, any other emission processing equipment, and any ECS
monitoring devices that are used pursuant to this rule or an air pollution permit.
b. Approval by Control Officer: An owner or operator shall submit to the Control
Officer for approval the O&M Plans of each ECS and each ECS monitoring
device that is used pursuant to this rule.
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c. Initial Plans: An owner or operator that is required to have an O&M Plan
pursuant to this rule shall comply with all O&M Plans that the owner or operator
has submitted for approval, but which have not yet been approved, unless
notified by the Control Officer in writing. Once the initial plan has been
approved in writing by the Control Officer, an owner or operator shall comply
with this approved plan.
d. Revisions to Plan: If revisions to the initial plan have been approved by the
Control Officer in writing, an owner or operator shall comply with the revisions
to the initial plan. If revisions to the plan have not yet been approved by the
Control Officer in writing, then an owner or operator shall comply with the most
recent O&M plan on file at Maricopa County Air Quality Department.
e. Control Officer Modifications to Plan: After discussion with the owner or
operator, the Control Officer may modify the plan in writing prior to approval of
the initial O&M plan. An owner or operator shall then comply with the plan that
has been modified by the Control Officer.
307.2 Submit to the Control Officer for approval an Operation and Maintenance (O&M)
Plan for any ECS and any ECS monitoring devices that are used pursuant to this rule
or to an air pollution permit. The O&M Plan shall include:
a. ECS equipment manufacturer; and
b. ECS equipment model; and
c. ECS equipment identification number; and
d. Operating parameters that will be monitored to demonstrate continued operation
of the ECS in the manner the ECS was operated during the most recent
performance test; and
e. The manufacturer’s recommended maintenance procedures and frequencies or, if
the manufacturer’s recommended maintenance procedures are not available, a
maintenance plan based on good engineering practice to reduce emissions.
307.3 Provide and maintain readily available on-site at all times the O&M Plan(s) for any
ECS and ECS monitoring devices that are used under this rule or an air pollution
control permit.
307.4 Fully comply with all the identified actions and schedules provided in the most
recent version of the O&M Plan submitted to the Control Officer, unless notified by
the Control Officer in writing.
307.5 Submit a revised O&M Plan within 30 business days following receipt of the Control
Officer's notice that an O&M Plan for any ECS, including any ECS monitoring
device, is deficient or inadequate.
308 EMERGENCY FUEL USE NOTIFICATION: Each time a combustion unit is fired
with emergency fuel, the owner or operator shall provide written notification to the Control
Officer within 2 business days after combustion of emergency fuel begins. The written
notification shall include a description of the emergency that necessitated the use of
emergency fuel, the date that combustion of emergency fuel began, and the expected
34

duration of the emergency fuel usage. The written notification may be submitted by mail,
email, fax, commercial delivery or hand delivery.
SECTION 400 – ADMINISTRATIVE REQUIREMENTS
401 COMPLIANCE SCHEDULE FOR PERFORMANCE TESTING: The owner or
operator of any combustion unit that becomes subject to the emission limits in Section 304.2
of this rule on or after [insert date of rule adoption] shall comply with following compliance
schedules, as applicable, and the associated deadlines for demonstrating compliance.
401.1 Performance Test: The owner or operator shall demonstrate compliance with the
applicable emission limits within 6 months after the combustion unit becomes
subject to the emission limits in Section 304.2 of this rule. This requirement shall not
apply to a combustion unit if modifications to an ECS or installation of an ECS is
required to achieve compliance with the applicable emission limits and the owner or
operator is in compliance with the applicable schedule in Section 401.3 or 401.4 of
this rule.
401.1 401.2 O&M Plan: Any owner or operator employing an approved ECS on the effective
date of this rule If different operating parameters or ECS maintenance procedures or
schedules are used to achieve compliance with the emission limits in Section 304.2 of
this rule, the owner or operator of the combustion unit shall by July 2, 2017 file an
submit a revised O&M Plan with the Control Officer in accordance with Section
306.3 307 of this rule within 30 days after completion of the performance test
required by Section 401.1 of this rule.
401.2 401.3 Modifications to Existing ECS: Any owner or operator required to modify their If
it is necessary to modify an ECS equipment or system by either reconstructing or
adding on equipment for compliance with this rule, an owner or operator shall by
July 2, 2017 file a schedule for the modification with submit to the Control Officer a
schedule for modification of the ECS within 6 months after the combustion unit
becomes subject to the emission limits in Section 304.2 of this rule. The plan
schedule shall show how the ECS is to be used to achieve full compliance and shall
specify dates for completing increments of progress. Any and all ECS used to
achieve such compliance shall be in operation by November 2, 2018. The owner or
operator shall complete ECS modifications and demonstrate compliance with the
applicable NOX emission limits within 12 months after the combustion unit becomes
subject to the emission limits in Section 304.2 of this rule.
401.3 401.4 ECS Installation: An owner or operator required to install If installation of an ECS
for is necessary to achieve compliance with numeric emission limits in this rule, an
owner or operator shall by July 2, 2017 file a schedule for the installation with submit
to the Control Officer a schedule for installation of the ECS within 6 months after
the equipment becomes subject to the emission limits in Section 304.2 of this rule.
The ECS shall then be installed and in compliance by November 2, 2019 The owner
or operator shall complete the installation of an ECS and demonstrate compliance
with the applicable NOX emission limits within 36 months after the combustion unit
becomes subject to the emission limits in Section 304.2 of this rule.
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402 COMPLIANCE SCHEDULE FOR RACT TUNING PROCEDURE: The owner or
operator of any combustion unit that becomes subject to the requirements of Section 304.4
of this rule on or after [insert date of rule adoption] shall complete the RACT tuning
procedure within 6 months after the combustion unit becomes subject to Section 304.4 of
this rule.
SECTION 500 – MONITORING AND RECORDS
501 RECORDKEEPING AND REPORTING: An owner or operator subject to this rule of
a combustion unit shall comply with the requirements set forth in this section. Any records
and data required by this section shall be kept on site at all times in a consistent and
complete manner and be made available without delay to the Control Officer or his designee
upon request. Records shall consist of the following information:
501.1 Equipment Listed in Section 102 of this Rule Combustion Units: Monthly records
of type and amount Type of fuel used, amount of fuel used, and amount of the
sulfur content of any liquid fuel or waste derived fuel gas combusted in the fuel if
using liquid fuel, and the days and hours of operation.
501.2 Emergency Fuel Usage: Monthly records of type and amount of emergency fuel
used, the sulfur content of the fuel, dates and hours of operation using emergency
fuel, and nature of the emergency or purpose for the use of the emergency fuel as
stated in Sections 104.1 and 104.2 and 104.3. Yearly records of the twelve month log
of hours of operation in the emergency mode using emergency fuel.
501.3 Good Combustion Practice: Measurements of the temperature differential across
the burners of turbines per Section 301.3 306 of this rule, results of evaluation and
corrective action taken to reduce the temperature differential or a finding that the
temperature differential returned to the range listed in Sections 301.3(a) 306.1 or
301.3(b) 306.2 of this rule without any action by the owner or operator.
501.4 Baseline Monitoring and Annual Tuning Procedure: Date that the procedure
was performed on the particular combustion unit and at a minimum: stack gas
temperature, flame conditions, nature of the adjustment and results of the nitrogen
oxide and carbon monoxide concentrations obtained by using a handheld portable
monitor after each adjustment.
501.5 RACT Tuning Procedure: Date the procedure was performed, the final control
settings that reflect optimized combustion, the firing rate during the tuning
procedure, a record of all adjustments and cleaning procedures, and a record of all
operating parameters specified in Appendix A.
501.6 Operation & Maintenance Records: On each day an ECS operates, record the ECS
operating parameters described in the O&M Plan. Record all maintenance actions
taken within 24 hours of maintenance completion. An explanation shall be recorded
for any scheduled maintenance that is not performed during the period designated in
the O&M Plan.
501.7 Continuous Emission Monitoring Systems: All CEMS measurements, results of
CEMS performance evaluations, CEMS calibration checks, and adjustments and
maintenance performed on these systems.
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502 RECORDS RETENTION: Copies of reports, logs and supporting documentation
required by the Control Officer shall be retained for at least 5 years. Records and
information required by this rule shall also be retained for at least 5 years.
503 COMPLIANCE DETERMINATION DEMONSTRATION:
503.1 Sulfur In Fuel Verification:
a. Ultra Low Sulfur Oil: If the Control Officer requests documentation of the
sulfur content of the fuel to demonstrate the 0.0015% limit, the owner or
operator shall submit one of the following:
(1) Fuel receipts, or
(2) Contract specifications, or
(3) Pipeline meter tickets, or
(4) Fuel supplier information, or
(5) Purchase records, or
(6) Test results of the fuel for sulfur content Analytical results listing the sulfur
content of the fuel, the test method conducted, and evidence that
appropriate chain of custody procedures were followed.
The items listed above must provide accurate sulfur content values or and be
based on enforceable test methods as approved by the Administrator to
determine the sulfur content.
b. Waste Derived Fuel Gas: The owner or operator shall submit documentation
of the concentration of the sulfur level content of the waste derived fuel gas to
the Control Officer upon request. The sulfur content of gaseous fuels shall be
determined by South Coast Air Quality Management District Method 307-91
Determination of Sulfur in a Gaseous Matrix.
c. Purchase Documentation of Existing Low Sulfur Oil: The owner or
operator shall maintain documentation of the purchase date of any low sulfur oil
on site to demonstrate the oil was purchased prior to November 2, 2016.
503.2 Gaseous Emissions-Source Test Requirements: Boilers with a heat input capacity
of 100 MMBtu per hour or greater, must conduct all applicable performance (stack)
tests on a triennial basis. Triennial performance tests must be completed no more
than 37 months after the previous performance test. The owner or operator of any
combustion unit that is subject to numeric emission limits in Section 301, 304
and/or 305 of this rule shall conduct performance tests at least once every 5 years.
The result of the performance test shall be the arithmetic mean of the results of
three test runs. Each test run shall have a minimum sample time of one hour. In
addition, the owner or operator shall comply with the following requirements:
a. Nitrogen oxides shall be measured using EPA Reference Method 7 or 7E and
carbon monoxide shall be measured using EPA Reference Method 10, as
incorporated by reference in Section 504 of this rule. For stationary gas turbines,
nitrogen oxides and carbon monoxide shall be measured dry and corrected to
37

15% oxygen. For all other combustion units, nitrogen oxides and carbon
monoxide shall be measured dry and corrected to 3% oxygen.
b. Particulate matter shall be measured using EPA Reference Method 5, or another
EPA-approved test method designated by the Control Officer. A back-half
analysis shall be performed using Reference Method 202 each time a
performance test is required.
c. The owner or operator may demonstrate compliance with applicable emission
limits by conducting representative performance testing if all of the following
requirements are satisfied:
(1) All combustion units in the specified group were produced by the same
manufacturer, have the same model number or other manufacturer’s
designation in common, and have the same rated heat input capacity and
operating specifications;
(2) All combustion units in the specified group are operated and maintained in a
similar manner;
(3) At least one combustion unit or one-third of the combustion units in the
specified group, whichever is greater, are tested each time a performance test
is required;
(4) Each time a performance test is required, different combustion units are
tested so that all combustion units in the specified group are tested before
any combustion units in the specified group are retested; and
(5) If emissions from any combustion unit in the specified group exceed an
applicable emission limit the owner or operator shall conduct a performance
test on each unit in the specified group to demonstrate that each combustion
unit in the specified group is in compliance with the applicable emission
limit.
503.3 Gaseous Emissions-Continuous Emission Monitoring System (CEMS):
Compliance with the emission requirements specified in Sections 301 through 304
305 of this rule may also be determined using CEMS. Where the combustion unit(s)
are equipped with CEMS:
a. General: All CEMS must be installed according to the procedures specified in 40
CFR 60.13(g). All CEMS shall be installed such that a representative
measurement of emissions is obtained. Additional procedures for the location of
CEMS found in 40 CFR 60, Appendix B shall be used. The data recorder for
CEMS shall be in operation at all times the combustion unit is operated.
b. Cycle Time: An owner or operator of any combustion unit using a CEMS shall
ensure that the CEMS completes a minimum of one cycle of operation
(sampling, analyzing, and data recording) for each successive 15-minute period.
c. Calibration: Zero and span shall be checked once every 24 hours. The CEMS
shall be calibrated in accordance with the manufacturer's specifications.
d. Averaging: The data recorded during periods of calibration checks, zero and
span adjustments shall not be included in averaging for compliance
38

determinations. Compliance shall be determined on an hourly basis using the
average of the 3 three previous 1 1-hour average emissions concentrations. The
1-hour average emissions concentration shall be determined from at least two
data points recorded by the CEMS.
e. Accuracy Testing Quality Assurance: Accuracy testing of The owner or
operator of the CEMS shall be conducted using a relative accuracy test audit
pursuant to fully comply with 40 CFR 60, Appendix F.
504 COMPLIANCE DETERMINATION-TEST METHODS INCORPORATED BY
REFERENCE: The following test methods are approved for use for the purpose of
determining compliance with this rule. The test methods are incorporated by reference in
Rule 360 and Appendix G of the Maricopa County Air Pollution Control Regulations.
Alternative test methods as approved by the Administrator or other EPA-approved test
methods may be used upon written approval from the Control Officer. When more than
one test method is permitted for the same determination, an exceedance under any method
will constitute a violation. Copies of test methods referenced in this section are available at
the Maricopa County Air Quality Department.
504.1 EPA Reference Methods 1 (“Sample and Velocity Traverses for Stationary
Sources”), and 1 A (“Sample and Velocity Traverses for Stationary Sources with
Small Stacks and Ducts”) (40 CFR 60, Appendix A).
504.2 EPA Reference Methods 2 (“Determination of Stack Gas Velocity and Volumetric
Flow Rate”), 2A (“Direct Measurement of Gas Volume through Pipes and Small
Ducts”), 2C (“Determination of Stack Gas Velocity and Volumetric Flow Rate in
Small Stacks or Ducts”), and 2D (“Measurement of Gas Volumetric Flow Rates in
Small Pipes and Ducts”) (40 CFR 60, Appendix A).
504.3 EPA Reference Methods 3 (“Gas Analysis for the Determination of Dry Molecular
Weight”), 3A (“Determination of Oxygen and Carbon Dioxide Concentrations in
Emissions from Stationary Sources (Instrumental Analyzer Procedure)”), 3B (“Gas
Analysis for the Determination of Emission Rate Correction Factor of or Excess
Air”), and 3C (“Determination of Carbon Dioxide, Methane, Nitrogen and Oxygen
from Stationary Sources”) (40 CFR 60, Appendix A).
504.4 EPA Reference Method 4 (“Determination of Moisture Content in Stack Gases”)
(40 CFR 60, Appendix A).
504.5 EPA Reference Method 5 (“Determination of Particulate Emissions from Stationary
Sources”) (40 CFR 60, Appendix A)
504.6 EPA Reference Method 202 (“Dry Impinger Method for Determination of
Condensable Particulate Emissions from Stationary Sources”) (40 CFR 51, Appendix
M).
504.7 EPA Reference Methods 7 (“Determination of Nitrogen Oxide Emissions from
Stationary Sources”), 7A (“Determination of Nitrogen Oxide Emissions form
Stationary Sources”), 7B (“Determination of Nitrogen Oxide Emissions from
Stationary Sources – Ultraviolet Spectrometry”), 7C (“Determination of Nitrogen
Oxide Emissions from Stationary Sources – Alkaline-Permanganate Colorimetric
Method”), 7D (“Determination of Nitrogen Oxide Emissions from Stationary
39

Sources – Alkaline-Permanganate Chromatographic Method”), and 7E
(“Determination of Nitrogen Oxide Emissions from Stationary Sources –
Instrumental Analyzer Method Procedure”), (40 CFR 60, Appendix A).
504.8 EPA Reference Method 9, (“Visual Determination of the Opacity of Emissions from
Stationary Sources”) (40 CFR 60, Appendix A).
504.9 EPA Reference Method 10, (“Determination of Carbon Monoxide from Stationary
Sources”) (40 CFR 60, Appendix A).
504.10 EPA Reference Method 20, (“Determination of Nitrogen Oxides, Sulfur Dioxide,
and Diluent Emissions from Stationary Gas Turbines”) (40 CFR 60, Appendix A).
504.11 ASTM Method D2622-98 D2622-05, (“Standard Test Method for Sulfur in
Petroleum Products by Wavelength Dispersive X-Ray Fluorescence Spectrometry”).
504.12 ASTM Method D2880-96 (“Standard Specification for Gas Turbine Fuel Oils”).
504.13 ASTM Method D4294-02 or D4294-03, (“Standard Test Method for Sulfur in
Petroleum and Petroleum Products by Energy-Dispersive X-Ray Fluorescence
Spectrometry”).
504.14 ASTM Method D5504-01 or D5504-08, (“Standard Test Method for Determination
of Sulfur compounds in Natural Gas and Gaseous Fuels by Gas Chromatography
and Chemiluminescence”).
504.15 South Coast Air Quality Management District Method 307-94 307-91
(“Determination of Sulfur in a Gaseous Matrix”), revised 1994.
40

APPENDIX A TO RULE 323
RACT TUNING PROCEDURES
Nothing in these equipment tuning procedures shall be construed to require any act or omission that
would result in unsafe conditions or would be in violation of any regulation of requirement
established by Factory Mutual, Industrial Risk Insurers, National Fire Prevention Association, the
Industrial Commission of Arizona (Arizona Division of Occupational Safety and Health), the
Federal Occupational Safety and Health Administration, or other relevant regulations and
requirements. Steps in these procedures that are not applicable to specific combustion units may be
omitted.
Tuning Procedure for Forced Draft Fired Boilers, Steam Generating Units, and Process
Heaters:
1. Operate the combustion unit at the firing rate most typical of normal operation. If the
combustion unit experiences significant load variations during normal operation, operate it
at its average firing rate.
2. At this firing rate, record the stack gas temperature, oxygen concentration, and CO
concentration (for gaseous fuels) or smoke-spot number1 (for liquid fuels), and observe
flame conditions after operation stabilizes at the firing rate selected. If the excess oxygen in
the stack gas is at the lower end of the range of typical minimum values2, and if CO
emissions are low and there is no smoke, the combustion unit is probably operating at near
optimum efficiency at this particular firing rate. Complete the remaining steps in this
procedure to determine whether still lower oxygen levels are practical.
3. Increase combustion air flow to the furnace until stack gas oxygen levels increase by one to
two percent over the level measured in Step 2 and record the stack gas temperature, oxygen
concentration, CO concentration (for gaseous fuels) or smoke-spot number (for liquid
fuels), and observe flame conditions for these higher oxygen levels after boiler operation
stabilizes.
4. Decrease combustion air flow until the stack gas oxygen concentration is at the level
measured in Step 2. From this level, gradually reduce the combustion air flow, in small
increments. After each increment, record the stack gas temperature, oxygen concentration,
CO concentration (for gaseous fuels) and smoke-spot number (for liquid fuels). Also
observe the flame and record any changes in its condition.
5. Continue to reduce combustion air flow stepwise, until one of these limits is reached:
a. Unacceptable flame conditions, such as flame impingement on furnace walls or burner
parts, excessive flame carryover, or flame instability;
b. Stack gas CO concentrations greater than 400 ppm;
c. Smoking at the stack; or
1 The smoke-spot number shall be determined with ASTM D2156.
2 Typical minimum oxygen levels for boilers firing at high firing rates are 0.5 – 3% (gaseous fuels) and 2 – 4% (liquid
fuels).
41

d. Equipment related limitations, such as low windbox/furnace pressure differential, built
in air-flow limits, etc.
6. Develop an O2/CO curve (for gaseous fuels) or O2/smoke curve (for liquid fuels) using the
excess oxygen and CO or smoke-spot number data obtained at each combustion air flow
setting.
7. From the O2/CO curve or the O2/smoke curve, find and record the stack gas oxygen levels
where the CO emissions or smoke-spot number equal the following values:
Fuel Measurement Value
Gaseous CO Emissions 400 ppm
#1 & #2 oils Smoke-spot number Number 1
#4 oils Smoke-spot number Number 2
#5 oils Smoke-spot number Number 3
Other oils Smoke-spot number Number 4
8. The stack gas oxygen level recorded in Step 7 is the minimum excess oxygen level (or the
CO/smoke threshold). Compare the minimum excess oxygen level to the expected value
provided by the combustion unit manufacturer. If the minimum level is found to be
substantially higher than the value provided by the combustion unit manufacturer, burner
adjustments can probably be made to improve fuel and air mixing, thereby allowing
operation with less air.
9. Increase the minimum excess oxygen level identified in Step 7 by 0.5 to 2.0 percent and reset
burner controls to operate automatically at this higher stack gas oxygen level. This margin
above minimum oxygen level accounts for fuel variations, variations in atmospheric
conditions, load changes, and nonrepeatability or play in automatic controls.
10. If the load of the combustion unit varies significantly during normal operation, repeat Steps
1 through 8 for firing rates that represent the upper and lower limits of the range of the load.
Because control adjustments at one firing rate may affect conditions at other firing rates, it
may not be possible to establish the optimum excess oxygen level at all firing rates. If this is
the case, choose the burner control settings that give best performance over the range of
firing rates. If one firing rate predominates, settings should optimize conditions at that firing
rate.
11. Verify that the new settings can accommodate the sudden changes that may occur in daily
operation without adverse effects. Do this by increasing and decreasing load rapidly while
observing the flame and stack. If any of the conditions in Step 5 result, reset the combustion
controls to provide a slightly higher level of excess oxygen. Verify the new settings in a
similar manner. The final control settings that reflect combustion optimization shall be
recorded for future reference.
Natural Draft Fired Boilers, Steam Generating Units, and Process Heaters:
42

1. Verify that the combustion unit is operating at the lowest pressure or temperature setting
that will satisfy load demand. This pressure or temperature will be used as a basis for
comparative combustion analysis before and after tuning.
2. Verify that the combustion unit will operate for the minimum number of hours necessary to
perform the tuning procedure.
3. Verify that the size of air supply openings is in compliance with applicable codes and
regulations. Air supply openings must be fully open when the burner is firing and air flow
must be unrestricted.
4. Verify that the vent is in good condition, properly sized, and free from obstruction.
5. Perform a combustion analysis at both high and low fire, if possible. Record the following
data for each combustion analysis:
a. The concentration of CO and oxygen;
b. Inlet fuel pressure at burner at high and low firing rates;
c. Steam pressure, water temperature, process fluid temperature, or temperature entering
and leaving the combustion unit; and
d. Inlet fuel use rate, if a meter is available.
6. Clean all dirty burners or burner orifices. Verify that fuel filters and moisture traps are in
place, clean, and operating properly. Confirm proper location and orientation of burner
diffuser spuds, gas canes, etc. Replace or repair damaged or missing burner parts.
7. Remove external and internal sediment and scale from heating surfaces.
8. Verify that the necessary water or process fluid treatment is being used. Confirm flushing
and/or blowdown schedule.
9. Repair all leaks. In addition to the high-pressure lines, check the blow-off, drain, safety valve,
bypass lines, and if used, the feed pump.
10. Perform the following safety checks:
a. Test primary and secondary low water level controls;
b. Check operating and limit pressure and temperature controls;
c. Check pilot safety shut off operation;
d. Check safety valve pressure setting and verify that the setting is consistent with load
requirements; and
e. Check limit safety control and spill switch.
11. Adjust the combustion unit to fire at the maximum inlet fuel use rate; record fuel manifold
pressure.
43

12. Adjust draft and/or fuel pressure to obtain acceptable, clean combustion at high, medium,
and low firing rates. The CO concentration should not exceed 400 ppm at 3% oxygen.
13. Verify that light-offs are smooth and safe. Perform a reduced fuel pressure test at both high
and low firing rates in accordance with the manufacturer’s instructions.
14. Check and adjust the modulation controller. Verify proper, efficient, and clean combustion
through the range of firing rates. When optimum performance has been achieved, record all
data.
15. Perform a final combustion analysis on the warm combustion unit at high, medium, and low
firing rates, if possible. Record data obtained from the combustion analysis as well as the
following information:
a. Inlet fuel pressure at burner at high and low firing rates;
b. Pressure above draft hood or barometric damper at high, medium, and low firing rates.
c. Steam pressure, water temperature, or process fluid pressure or temperature entering and
leaving the combustion unit; and
d. Inlet fuel use rate if a meter is available.
44

Return to list of attachments
MARICOPA COUNTY
AIR POLLUTION CONTROL REGULATIONS
REGULATION III – CONTROL OF AIR CONTAMINANTS
RULE 323
FUEL BURNING EQUIPMENT FROM
INDUSTRIAL/COMMERCIAL/INSTITUTIONAL (ICI) SOURCES
INDEX
SECTION 100 – GENERAL
101 PURPOSE
102 APPLICABILITY
103 EXEMPTIONS
104 PARTIAL EXEMPTIONS
SECTION 200 – DEFINITIONS
201 ALTERNATIVE FUELS
202 ANNUAL HEAT INPUT
203 BOILER
204 COGENERATION STEAM GENERATING UNIT
205 COMBUSTION CONTROL SYSTEM
206 COMBUSTION UNIT
207 CONTINUOUS EMISSIONS MONITORING SYSTEM (CEMS)
208 CORRECTIVE ACTION PLAN (CAP)
209 EMERGENCY FUEL
210 EMISSION CONTROL SYSTEM (ECS)
211 FOSSIL FUEL
212 GAS TURBINE
213 HEAT INPUT
214 LOW SULFUR OIL
215 NATURAL GAS CURTAILMENT
216 OPACITY
217 OPERATING HOUR
218 PARTICULATE MATTER EMISSIONS
219 PARTS PER MILLION BY VOLUME DRY (PPMVD)
220 PEAK LOAD
45

221 PROCESS HEATER
222 RATED HEAT INPUT CAPACITY
223 STATIONARY GAS TURBINE
224 STEAM GENERATING UNIT
225 SULFUR OXIDES (SOX)
226 ULTRA LOW SULFUR OIL
227 UNCOMBINED WATER
228 WASTE DERIVED FUEL GAS
229 WATER HEATER
SECTION 300 – STANDARDS
301 LIMITATIONS - PARTICULATE MATTER
302 LIMITATIONS - OPACITY
303 LIMITATIONS - SULFUR IN FUEL
304 LIMITATIONS - NITROGEN OXIDES
305 LIMITATIONS - CARBON MONOXIDE
306 GOOD COMBUSTION PRACTICES FOR STATIONARY GAS TURBINES
307 REQUIREMENTS FOR ECS AND ECS MONITORING EQUIPMENT
308 EMERGENCY FUEL USE NOTIFICATION
SECTION 400 – ADMINISTRATIVE REQUIREMENTS
401 COMPLIANCE SCHEDULE FOR PERFORMANCE TESTING
402 COMPLIANCE SCHEDULE FOR RACT TUNING PROCEDURE
SECTION 500 – MONITORING AND RECORDS
501 RECORDKEEPING AND REPORTING
502 RECORDS RETENTION
503 COMPLIANCE DEMONSTRATION
504 COMPLIANCE DETERMINATION-TEST METHODS INCORPORATED BY
REFERENCE
APPENDIX A TO RULE 323
46

Adopted 07/02/2003; Revised 10/17/2007; Revised 11/02/2016; Revised MM/DD/YYYY
MARICOPA COUNTY
AIR POLLUTION CONTROL REGULATIONS
REGULATION III-CONTROL OF AIR CONTAMINANTS
RULE 323
FUEL BURNING EQUIPMENT FROM INDUSTRIAL/COMMERCIAL/INSTITUTIONAL (ICI)
SOURCES
SECTION 100 – GENERAL
101 PURPOSE: To limit the discharge of nitrogen oxides, sulfur oxides, carbon monoxide, and
particulate matter emissions into the atmosphere from fuel burning combustion units at
industrial and/or commercial and/or institutional (ICI) sources.
102 APPLICABILITY: This rule applies to the following types of combustion units that burn
either fossil fuels or alternative fuels:
102.1 Each boiler or steam generating unit that has a maximum design rated heat input
capacity greater than 10 million (MM) British thermal units per hour (Btu/hr).
102.2 Each stationary gas turbine with a heat input at peak load equal to or greater than 10
MMBtu/hr.
102.3 Each cogeneration steam generating unit with a heat input of greater than 10
MMBtu/hr.
102.4 Each indirect-fired process heater with a heat input greater than 10 MMBtu/hr.
102.5 NSPS & NESHAP: In addition to this rule, facilities may be subject to New Source
Performance Standards (NSPS) in Rule 360 and/or National Emission Standards for
Hazardous Air Pollutants (NESHAP) in Rule 370 of these rules.
103 EXEMPTIONS: This rule shall not apply to the following types of equipment:
103.1 Incinerators, crematories, or burn-off ovens; or
103.2 Dryers, cement and lime kilns; or
103.3 Direct-fired process heaters; or
103.4 Medical waste incinerators; or
103.5 Reciprocating internal combustion engines; or
103.6 Combustion equipment used in power plant operations for the purpose of supplying
greater than one third of the electricity to any utility power distribution system for
sale; or
103.7 Combustion equipment associated with nuclear power plant operations; or
103.8 Water heaters used for the sole purpose of heating water for comfort or for radiant
heat; or
103.9 Municipal solid waste landfill enclosed combustors and non-enclosed flares.
47

104 PARTIAL EXEMPTIONS:
104.1 Stationary gas turbines listed in Section 102.2 of this rule that are used for any of the
following reasons shall be exempt from Sections 301, 304, and 305, of this rule:
a. Used for firefighting; or
b. Used for flood control; or
c. Engaged by manufacturers in research and the development of equipment for
either gas turbine emission control techniques or gas turbine efficiency
improvements.
104.2 All combustion units that are normally fired with natural gas shall be exempt from
Sections 301, 304, 305, and 501.1 of this rule while firing emergency fuel during a
natural gas curtailment or a natural gas emergency. For combustion units located at a
major stationary source of nitrogen oxides, this exemption shall not exceed 168
hours per calendar year per combustion unit, excluding hours of operation for
testing, reliability, training, and maintenance.
104.3 All combustion units that are normally fired with natural gas shall be exempt from
Sections 301, 304, 305, and 501.1 of this rule while firing emergency fuel for the
purposes of testing, reliability, training, and maintenance. This exemption shall not
exceed 36 hours per calendar year per combustion unit, excluding hours of operation
during natural gas curtailments and natural gas emergencies.
SECTION 200 – DEFINITIONS: For the purpose of this rule, the following definitions shall
apply, in addition to those definitions found in Rule 100 (General Provisions and Definitions) of these
rules. In the event of any inconsistency between any of the Maricopa County air pollution control
rules, the definitions in this rule take precedence.
201 ALTERNATIVE FUELS: Substitutes for traditional oil-derived and fossil-fuel derived
motor vehicle fuels including but not limited to biodiesel, propane, ethanol, methanol, or
waste derived fuel gas.
202 ANNUAL HEAT INPUT: The actual total heat input of fuels combusted in a unit during
a calendar year, as calculated based on the amount of each fuel combusted and the higher
heating value of each fuel. Annual heat input shall not include the heat input from
emergency fuel combusted during natural gas curtailments and natural gas emergencies or
emergency fuel combusted for purposes of testing, reliability, training, and maintenance as
long as the usage limits in Sections 104.2 and 104.3 are not exceeded.
203 BOILER: A device that combusts any fossil fuel or alternative fuel and recovers thermal
energy to heat water or another material.
204 COGENERATION STEAM GENERATING UNIT: Any device that is fired with
fossil fuels or alternative fuels and simultaneously produces both useful thermal energy (such
as heat or steam) and either electrical or mechanical energy from the same primary energy
source.
205 COMBUSTION CONTROL SYSTEM: Equipment or technology, such as water
injection or low-NOX burners, that reduce the formation of nitrogen oxides during
combustion of fossil fuels or alternative fuels.
48

206 COMBUSTION UNIT: Any boiler, steam generating unit, stationary gas turbine,
cogeneration steam generating unit, or indirect-fired process heater listed in Section 102 of
this rule.
207 CONTINUOUS EMISSIONS MONITORING SYSTEM (CEMS): The total
equipment required to sample, analyze, measure, and provide a permanent record of
emissions by means of readings recorded at least once every 15 minutes (using an automated
data acquisition and handling system (DAHS)).
208 CORRECTIVE ACTION PLAN (CAP): A methodical procedure that is used to evaluate
and correct a turbine operational problem and that includes, at a minimum, improved
preventative maintenance procedures, improved ECS operating practices, possible
operational amendments, and progress reports.
209 EMERGENCY FUEL: Fuel fired only for purposes of testing, reliability, training, and
maintenance or during circumstances such as a natural gas emergency or a natural gas
curtailment, or breakdown of delivery system such as an unavoidable interruption of supply
that makes it impossible to fire natural gas in the combustion unit. Fuel is not considered
emergency fuel if it is used to avoid either peak demand charges or high gas prices during
on-peak price periods or due to a voluntary reduction in natural gas usage.
210 EMISSION CONTROL SYSTEM (ECS): Post-combustion systems that are approved in
writing by the Control Officer and are designed and operated in accordance with good
engineering practice to reduce emissions from combustion equipment. A combustion
control system is not an emission control system.
211 FOSSIL FUEL: Naturally occurring carbonaceous substances from the ground such as
natural gas, petroleum, coal, and any form of solid, liquid or gaseous fuel derived from such
material for the purpose of creating energy.
212 GAS TURBINE: A rotary engine driven by the expansion of hot gases that are generated
by the combustion of fuel.
213 HEAT INPUT: Heat derived from the combustion of fuel not including the heat input
from preheated combustion air, recirculated flue gases, or exhaust gases from other sources,
such as gas turbines, internal combustion engines, and kilns.
214 LOW SULFUR OIL: Fuel oil containing less than or equal to 0.05% sulfur by weight.
215 NATURAL GAS CURTAILMENT: A shortage in the supply of natural gas, due solely to
limitations or restrictions in distribution pipelines by the utility supplying the gas and not due
to the cost of natural gas.
216 OPACITY: A condition of the ambient air, or any part thereof, in which an air contaminant
partially or wholly obscures the view of an observer.
217 OPERATING HOUR: A clock hour during which a unit combusts fuel, either for part of
the hour or for the entire hour.
218 PARTICULATE MATTER EMISSIONS: Any and all particulate matter emitted to the
ambient air as measured by applicable state and federal test methods.
219 PARTS PER MILLION BY VOLUME DRY (PPMVD): A unit of proportion used to
express concentration that is corrected to a dry basis.
49

220 PEAK LOAD: 100% of the manufacturer’s design capacity of a gas turbine at 288° Kelvin,
60% relative humidity, and 101.3 kilopascals pressure (ISO 3977 standard reference
conditions and ratings).
221 PROCESS HEATER: An enclosed combustion device that uses controlled flame to
transfer heat to a process fluid or a process material that is not a fluid or to heat transfer
material for use in a process unit (not including the generation of steam). A process heater
may be either indirect or direct-fired, dependent upon whether the gases of combustion mix
with and exhaust to the same stack or vent (direct-fired) with gases emanating from the
process material or not (indirect-fired). Emissions from indirect-fired units consist entirely of
products of combustion while emissions from direct-fired units are unique to the given
process and may vary widely in any industrial process. A process heater is not an oven or
kiln used for drying, curing, baking, cooking, calcining, or vitrifying.
222 RATED HEAT INPUT CAPACITY: The heat input capacity as specified on the
nameplate of the combustion unit. If the combustion unit has been altered or modified so
that its maximum heat input is different than the heat input capacity on the nameplate
(design heat capacity), the maximum heat input shall be considered as the rated heat input
capacity.
223 STATIONARY GAS TURBINE: Any gas turbine that is not self-propelled or that is
attached to a foundation.
224 STEAM GENERATING UNIT: A device that combusts any fossil fuel or alternative fuel
and produces steam or heats water or heats any heat transfer medium.
225 SULFUR OXIDES (SOX): The sum of the oxides of sulfur emitted from the flue gas from
a combustion unit that are directly dependent upon the amount of sulfur in the fuel used.
226 ULTRA LOW SULFUR OIL: Fuel oil containing less than or equal to 0.0015 % sulfur by
weight.
227 UNCOMBINED WATER: Condensed water containing no more than analytical trace
amounts of other chemical elements or compounds.
228 WASTE DERIVED FUEL GAS: A gaseous fuel that is generated from the biodegradation
of solid or liquid waste including, but not limited to, digester gas and landfill gas.
229 WATER HEATER: A closed vessel in which water is heated by combustion of fuel and
water is either withdrawn for use external to the vessel (at pressures not exceeding 160 psi
with all controls and devices preventing water temperatures from exceeding 210°F) or used
for radiant heat. Water heaters are usually no larger than 1 MM Btu/hr and do not reach
temperatures of 220°F and higher.
SECTION 300 – STANDARDS
301 LIMITATIONS – PARTICULATE MATTER: An owner or operator of any
combustion unit with either a rated heat input capacity or heat input greater than 100
MMBtu/hr shall not discharge, cause, or allow the discharge of particulate matter emissions,
caused by combustion of non-gaseous liquid fuels or a blend of liquid fuels with other fuels,
in excess of 0.10 pounds/MMBtu.
50

302 LIMITATIONS – OPACITY: An owner or operator shall not discharge into the ambient
air from any single source of emissions any air contaminant, other than uncombined water,
in excess of 20% opacity.
303 LIMITATIONS – SULFUR IN FUEL: An owner or operator of any combustion unit
that burns fuel oil or a mixture or blend of fuel oil with any other fuels shall use only ultra
low sulfur oil. An existing supply of low sulfur oil purchased or obtained prior to November
2, 2016 may be used until depleted. An owner or operator of any combustion unit that burns
waste derived fuel gas shall use only waste derived fuel gas that contains no more than
0.08% sulfur by weight, alone or in combination with other fuels.
304 LIMITATIONS – NITROGEN OXIDES: An owner or operator of any combustion
unit shall comply with the subsections specified in Table 323-1.
TABLE 323-1
FOR COMBUSTION UNITS THAT ARE NOT THE OWNER OR
LOCATED AT A MAJOR SOURCE OF OPERATOR SHALL
NITROGEN OXIDES: COMPLY WITH:
Stationary gas turbines 304.1 and 304.2
Combustion units (>100 MMBtu/hr) except stationary gas 304.3
turbines
Combustion units (≤ 100 MMBtu/hr) except stationary gas 304.1 or 304.2 or 304.4*
turbines
FOR COMBUSTION UNITS THAT ARE THE OWNER OR
LOCATED AT A MAJOR SOURCE OF OPERATOR SHALL
NITROGEN OXIDES: COMPLY WITH:
Stationary gas turbines 304.1 and 304.2
Combustion units (> 100 MMBtu/hour) except stationary 304.3
gas turbines
Combustion units (> 50 MMBtu/hour and ≤ 100 304.2
MMBtu/hour) except stationary gas turbines
Combustion units (> 10 MMBtu/hour and ≤ 50 304.2 or 304.4*
MMBtu/hour with annual heat input ≥ 220,000 therms)
except stationary gas turbines
Combustion units (> 10 MMBtu/hour and ≤ 50 304.1 or 304.2 or 304.4*
MMBtu/hour with annual heat input < 220,000 therms)
except stationary gas turbines
* The RACT tuning procedures in Section 304.4 are not appropriate for combustion units equipped with Low-
NOX burners or burners utilizing a premix flame.
304.1 Baseline Monitoring and Annual Tuning:
a. Establish and record the initial optimal baseline concentrations for NOX and CO
within 90 days of the first usage of the combustion unit utilizing the initial design
burner specifications or manufacturer’s recommendations to ensure good
combustion practices. The initial design burner specifications or manufacturer’s
recommendations shall be kept onsite and available to the Control Office upon
request.
b. Tune the combustion unit annually in accordance with the manufacturer’s
recommended procedure. The manufacturer’s recommended procedures shall be
51

kept onsite and available to the Control Officer upon request. For low emission
burner systems that do not provide accessibility for combustion chamber
inspection, burner inspection, or inspection of the flame pattern, an owner or
operator shall provide documentation from the manufacturer and follow the
manufacturer’s recommended procedure. If the manufacturer’s recommended
tuning procedure is not available, the owner or operator shall tune the
combustion unit annually by following, at a minimum, the steps listed in
304.1b.(1) – (5), if the combustion unit is so equipped, and if such procedures are
appropriate to the type of combustion unit:
(1) Inspect the burner system and clean and replace any components of the
burner as necessary to minimize emissions of NOX and CO; and
(2) Inspect the burner chamber for areas of impingement and remove if
necessary; and
(3) Inspect the flame pattern and make adjustments as necessary to optimize the
flame pattern; and
(4) Inspect the system controlling the air-to-fuel ratio and ensure that it is
correctly calibrated and functioning properly; and
(5) Using a portable monitor, measure the NOX and CO concentration of the
effluent stream after each adjustment is made to ensure optimal baseline
concentrations are maintained.
304.2 RACT Emission Limits: Limit nitrogen oxide emissions to no more than the
following amounts:
a. Stationary Gas Turbines:
(1) 42 ppmvd corrected to 15% oxygen calculated as nitrogen dioxide, when
burning gaseous fuel.
(2) 65 ppmvd corrected to 15% oxygen calculated as nitrogen dioxide, when
burning liquid fuel.
b. All Combustion Units Except Stationary Gas Turbines:
(1) 30 ppmvd corrected to 3% oxygen calculated as nitrogen dioxide, when
burning gaseous fuel.
(2) 40 ppmvd corrected to 3% oxygen calculated as nitrogen dioxide, when
burning liquid fuel.
304.3 Semi-Annual Tuning and RACT Emission Limits:
a. Tune the combustion unit every 6 months in accordance with the manufacturer’s
recommended procedure or in accordance with the procedures listed in Section
304.1.b(1) through (5) of this rule and;
b. Meet the RACT emission limits as stated in Section 304.2 of this rule.
304.4 RACT Tuning Procedures: Tune the combustion unit every 12 months using the
procedure in Appendix A of this rule that is appropriate for the combustion unit.
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305 LIMITATIONS-CARBON MONOXIDE: An owner or operator of any combustion
unit with a heat input greater than 100 MMBtu/hr shall not cause to be discharged into the
atmosphere, carbon monoxide (CO), measured in excess of 400 ppmvd corrected to 15%
oxygen for Stationary Gas Turbines, and corrected to 3% oxygen for all Combustion Units
Except Stationary Gas Turbines.
306 GOOD COMBUSTION PRACTICES FOR STATIONARY GAS TURBINES: The
owner or operator of any stationary gas turbine listed in Section 102.2 of this rule shall,
regardless of fuel type, use operational practices recommended by the manufacturer to
ensure good combustion control. The owner or operator of any stationary gas turbine listed
in Section 102.2 of this rule shall demonstrate good combustion control using the parametric
monitoring method listed below, or by operating a continuous emissions monitoring system
to demonstrate compliance with the limits in Sections 304 and 305 of this rule, as applicable.
306.1 Monitor the maximum temperature differential across the combustion burners or at
locations around the back end of the turbine, dependent upon the particular unit, to
ensure no more than a 100F difference using a thermocouple. Differential
temperatures shall be measured and recorded at least once during every operating
hour. If a temperature differential of greater than 100F is observed across the
burners, investigation and corrective action shall be taken within three hours to
reduce the temperature difference to 100F or less.
306.2 If the manufacturer recommends that the maximum numerical temperature
differential to ensure good combustion is greater than 100°F, then proof of this
maximum alternate temperature differential shall be submitted to the Control
Officer. The procedure to measure the maximum temperature differential listed in
Section 306.1 of this rule shall then be followed using this alternate recommended
maximum temperature differential after approval by the Control Officer.
306.3 If the differential temperature exceeds 100°F, or the alternate temperature
differential recommended by the manufacturer and approved by the Control Officer,
during three consecutive operating hours, the operator shall comply with the
recordkeeping requirements in Section 501.3 of this rule. If this occurs more than 3
times in 3 months, the owner or operator shall notify the Control Officer in writing
within 2 business days and the Control Officer shall require the owner or operator to
submit a Corrective Action Plan (CAP).
307 REQUIREMENTS FOR ECS AND ECS MONITORING EQUIPMENT: If an ECS
is operated during a performance test required by Section 503 of this rule, the owner or
operator shall:
307.1 Properly install, operate, and maintain in calibration and in good working order,
devices for indicating temperatures, pressures, transfer rates, rates of flow, or other
operating conditions necessary to determine if air pollution control equipment is
functioning properly and is properly maintained.
307.2 Submit to the Control Officer for approval an Operation and Maintenance (O&M)
Plan for any ECS and any ECS monitoring devices that are used pursuant to this rule
or to an air pollution permit. The O&M Plan shall include:
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a. ECS equipment manufacturer; and
b. ECS equipment model; and
c. ECS equipment identification number; and
d. Operating parameters that will be monitored to demonstrate continued operation
of the ECS in the manner the ECS was operated during the most recent
performance test; and
e. The manufacturer’s recommended maintenance procedures and frequencies or, if
the manufacturer’s recommended maintenance procedures are not available, a
maintenance plan based on good engineering practice to reduce emissions.
307.3 Provide and maintain readily available on-site at all times the O&M Plan(s) for any
ECS and ECS monitoring devices that are used under this rule or an air pollution
control permit.
307.4 Fully comply with all the identified actions and schedules provided in the most
recent version of the O&M Plan submitted to the Control Officer, unless notified by
the Control Officer in writing.
307.5 Submit a revised O&M Plan within 30 business days following receipt of the Control
Officer's notice that an O&M Plan for any ECS, including any ECS monitoring
device, is deficient or inadequate.
308 EMERGENCY FUEL USE NOTIFICATION: Each time a combustion unit is fired
with emergency fuel, the owner or operator shall provide written notification to the Control
Officer within 2 business days after combustion of emergency fuel begins. The written
notification shall include a description of the emergency that necessitated the use of
emergency fuel, the date that combustion of emergency fuel began, and the expected
duration of the emergency fuel usage. The written notification may be submitted by mail,
email, fax, commercial delivery or hand delivery.
SECTION 400 – ADMINISTRATIVE REQUIREMENTS
401 COMPLIANCE SCHEDULE FOR PERFORMANCE TESTING: The owner or
operator of any combustion unit that becomes subject to the emission limits in Section 304.2
of this rule on or after [insert date of rule adoption] shall comply with following compliance
schedules, as applicable, and the associated deadlines for demonstrating compliance.
401.1 Performance Test: The owner or operator shall demonstrate compliance with the
applicable emission limits within 6 months after the combustion unit becomes
subject to the emission limits in Section 304.2 of this rule. This requirement shall not
apply to a combustion unit if modifications to an ECS or installation of an ECS is
required to achieve compliance with the applicable emission limits and the owner or
operator is in compliance with the applicable schedule in Section 401.3 or 401.4 of
this rule.
401.2 O&M Plan: If different operating parameters or ECS maintenance procedures or
schedules are used to achieve compliance with the emission limits in Section 304.2 of
this rule, the owner or operator of the combustion unit shall submit a revised O&M
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Plan in accordance with Section 307 of this rule within 30 days after completion of
the performance test required by Section 401.1 of this rule.
401.3 Modifications to Existing ECS: If it is necessary to modify an ECS by either
reconstructing or adding on equipment , an owner or operator shall submit to the
Control Officer a schedule for modification of the ECS within 6 months after the
combustion unit becomes subject to the emission limits in Section 304.2 of this rule.
The schedule shall show how the ECS is to be used to achieve full compliance and
shall specify dates for completing increments of progress. The owner or operator
shall complete ECS modifications and demonstrate compliance with the applicable
NOX emission limits within 12 months after the combustion unit becomes subject to
the emission limits in Section 304.2 of this rule.
401.4 ECS Installation: If installation of an ECS is necessary to achieve compliance with
numeric emission limits in this rule, an owner or operator shall submit to the Control
Officer a schedule for installation of the ECS within 6 months after the equipment
becomes subject to the emission limits in Section 304.2 of this rule. The owner or
operator shall complete the installation of an ECS and demonstrate compliance with
the applicable NOX emission limits within 36 months after the combustion unit
becomes subject to the emission limits in Section 304.2 of this rule.
402 COMPLIANCE SCHEDULE FOR RACT TUNING PROCEDURE: The owner or
operator of any combustion unit that becomes subject to the requirements of Section 304.4
of this rule on or after [insert date of rule adoption] shall complete the RACT tuning
procedure within 6 months after the combustion unit becomes subject to Section 304.4 of
this rule.
SECTION 500 – MONITORING AND RECORDS
501 RECORDKEEPING AND REPORTING: An owner or operator of a combustion unit
shall comply with the requirements set forth in this section. Any records and data required
by this section shall be kept on site at all times in a consistent and complete manner and be
made available without delay to the Control Officer or his designee upon request. Records
shall consist of the following information:
501.1 Combustion Units: Monthly records of type and amount of fuel used, and the
sulfur content of any liquid fuel or waste derived fuel gas combusted.
501.2 Emergency Fuel Usage: Monthly records of type and amount of emergency fuel
used, the sulfur content of the fuel, dates and hours of operation using emergency
fuel, and nature of the emergency or purpose for the use of the emergency fuel as
stated in Sections 104.2 and 104.3. Yearly records of the twelve month log of hours
of operation using emergency fuel.
501.3 Good Combustion Practice: Measurements of the temperature differential across
the burners of turbines per Section 306 of this rule, results of evaluation and
corrective action taken to reduce the temperature differential or a finding that the
temperature differential returned to the range listed in Sections 306.1 or 306.2 of this
rule without any action by the owner or operator.
501.4 Baseline Monitoring and Annual Tuning Procedure: Date that the procedure
was performed on the particular combustion unit and at a minimum: stack gas
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temperature, flame conditions, nature of the adjustment and results of the nitrogen
oxide and carbon monoxide concentrations obtained by using a portable monitor
after each adjustment.
501.5 RACT Tuning Procedure: Date the procedure was performed, the final control
settings that reflect optimized combustion, the firing rate during the tuning
procedure, a record of all adjustments and cleaning procedures, and a record of all
operating parameters specified in Appendix A.
501.6 Operation & Maintenance Records: On each day an ECS operates, record the ECS
operating parameters described in the O&M Plan. Record all maintenance actions
taken within 24 hours of maintenance completion. An explanation shall be recorded
for any scheduled maintenance that is not performed during the period designated in
the O&M Plan.
501.7 Continuous Emission Monitoring Systems: All CEMS measurements, results of
CEMS performance evaluations, CEMS calibration checks, and adjustments and
maintenance performed on these systems.
502 RECORDS RETENTION: Copies of reports, logs and supporting documentation
required by the Control Officer shall be retained for at least 5 years. Records and
information required by this rule shall also be retained for at least 5 years.
503 COMPLIANCE DEMONSTRATION:
503.1 Sulfur Verification:
a. Ultra Low Sulfur Oil: If the Control Officer requests documentation of the
sulfur content of the fuel to demonstrate the 0.0015% limit, the owner or
operator shall submit one of the following:
(1) Fuel receipts, or
(2) Contract specifications, or
(3) Pipeline meter tickets, or
(4) Fuel supplier information, or
(5) Purchase records, or
(6) Analytical results listing the sulfur content of the fuel, the test method
conducted, and evidence that appropriate chain of custody procedures were
followed.
The items listed above must provide accurate sulfur content values and be based
on enforceable test methods as approved by the Administrator to determine the
sulfur content.
b. Waste Derived Fuel Gas: The owner or operator shall submit documentation
of the sulfur content of the waste derived fuel gas to the Control Officer upon
request. The sulfur content of gaseous fuels shall be determined by South Coast
Air Quality Management District Method 307-91 Determination of Sulfur in a
Gaseous Matrix.
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c. Purchase Documentation of Existing Low Sulfur Oil: The owner or
operator shall maintain documentation of the purchase date of any low sulfur oil
on site to demonstrate the oil was purchased prior to November 2, 2016.
503.2 Source Test Requirements: The owner or operator of any combustion unit that is
subject to numeric emission limits in Section 301, 304 and/or 305 of this rule shall
conduct performance tests at least once every 5 years. The result of the performance
test shall be the arithmetic mean of the results of three test runs. Each test run shall
have a minimum sample time of one hour. In addition, the owner or operator shall
comply with the following requirements:
a. Nitrogen oxides shall be measured using EPA Reference Method 7 or 7E and
carbon monoxide shall be measured using EPA Reference Method 10, as
incorporated by reference in Section 504 of this rule. For stationary gas turbines,
nitrogen oxides and carbon monoxide shall be measured dry and corrected to
15% oxygen. For all other combustion units, nitrogen oxides and carbon
monoxide shall be measured dry and corrected to 3% oxygen.
b. Particulate matter shall be measured using EPA Reference Method 5, or another
EPA-approved test method designated by the Control Officer. A back-half
analysis shall be performed using Reference Method 202 each time a
performance test is required.
c. The owner or operator may demonstrate compliance with applicable emission
limits by conducting representative performance testing if all of the following
requirements are satisfied:
(1) All combustion units in the specified group were produced by the same
manufacturer, have the same model number or other manufacturer’s
designation in common, and have the same rated heat input capacity and
operating specifications;
(2) All combustion units in the specified group are operated and maintained in a
similar manner;
(3) At least one combustion unit or one-third of the combustion units in the
specified group, whichever is greater, are tested each time a performance test
is required;
(4) Each time a performance test is required, different combustion units are
tested so that all combustion units in the specified group are tested before
any combustion units in the specified group are retested; and
(5) If emissions from any combustion unit in the specified group exceed an
applicable emission limit the owner or operator shall conduct a performance
test on each unit in the specified group to demonstrate that each combustion
unit in the specified group is in compliance with the applicable emission
limit.
503.3 Gaseous Emissions-Continuous Emission Monitoring System (CEMS):
Compliance with the emission requirements specified in Sections 301 through 305 of
this rule may also be determined using CEMS. Where the combustion unit(s) are
equipped with CEMS:
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a. General: All CEMS must be installed according to the procedures specified in 40
CFR 60.13(g). All CEMS shall be installed such that a representative
measurement of emissions is obtained. Additional procedures for the location of
CEMS found in 40 CFR 60, Appendix B shall be used. The data recorder for
CEMS shall be in operation at all times the combustion unit is operated.
b. Cycle Time: An owner or operator of any combustion unit using a CEMS shall
ensure that the CEMS completes a minimum of one cycle of operation
(sampling, analyzing, and data recording) for each successive 15-minute period.
c. Calibration: Zero and span shall be checked once every 24 hours. The CEMS
shall be calibrated in accordance with the manufacturer's specifications.
d. Averaging: The data recorded during periods of calibration checks, zero and
span adjustments shall not be included in averaging for compliance
determinations. Compliance shall be determined on an hourly basis using the
average of the three previous 1-hour average emissions concentrations. The 1-
hour average emissions concentration shall be determined from at least two data
points recorded by the CEMS.
e. Quality Assurance: The owner or operator of the CEMS shall fully comply
with 40 CFR 60, Appendix F.
504 COMPLIANCE DETERMINATION-TEST METHODS INCORPORATED BY
REFERENCE: The following test methods are approved for use for the purpose of
determining compliance with this rule. The test methods are incorporated by reference in
Rule 360 and Appendix G of the Maricopa County Air Pollution Control Regulations.
Alternative test methods as approved by the Administrator or other EPA-approved test
methods may be used upon written approval from the Control Officer. When more than
one test method is permitted for the same determination, an exceedance under any method
will constitute a violation. Copies of test methods referenced in this section are available at
the Maricopa County Air Quality Department.
504.1 EPA Reference Methods 1 (“Sample and Velocity Traverses for Stationary
Sources”), and 1 A (“Sample and Velocity Traverses for Stationary Sources with
Small Stacks and Ducts”) (40 CFR 60, Appendix A).
504.2 EPA Reference Methods 2 (“Determination of Stack Gas Velocity and Volumetric
Flow Rate”), 2A (“Direct Measurement of Gas Volume through Pipes and Small
Ducts”), 2C (“Determination of Stack Gas Velocity and Volumetric Flow Rate in
Small Stacks or Ducts”), and 2D (“Measurement of Gas Volumetric Flow Rates in
Small Pipes and Ducts”) (40 CFR 60, Appendix A).
504.3 EPA Reference Methods 3 (“Gas Analysis for the Determination of Dry Molecular
Weight”), 3A (“Determination of Oxygen and Carbon Dioxide Concentrations in
Emissions from Stationary Sources (Instrumental Analyzer Procedure)”), 3B (“Gas
Analysis for the Determination of Emission Rate Correction Factor or Excess Air”),
and 3C (“Determination of Carbon Dioxide, Methane, Nitrogen and Oxygen from
Stationary Sources”) (40 CFR 60, Appendix A).
504.4 EPA Reference Method 4 (“Determination of Moisture Content in Stack Gases”)
(40 CFR 60, Appendix A).
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504.5 EPA Reference Method 5 (“Determination of Particulate Emissions from Stationary
Sources”) (40 CFR 60, Appendix A)
504.6 EPA Reference Method 202 (“Dry Impinger Method for Determination of
Condensable Particulate Emissions from Stationary Sources”) (40 CFR 51, Appendix
M).
504.7 EPA Reference Methods 7 (“Determination of Nitrogen Oxide Emissions from
Stationary Sources”) and 7E (“Determination of Nitrogen Oxide Emissions from
Stationary Sources – Instrumental Analyzer Procedure”), (40 CFR 60, Appendix A).
504.8 EPA Reference Method 9, (“Visual Determination of the Opacity of Emissions from
Stationary Sources”) (40 CFR 60, Appendix A).
504.9 EPA Reference Method 10, (“Determination of Carbon Monoxide from Stationary
Sources”) (40 CFR 60, Appendix A).
504.10 EPA Reference Method 20, (“Determination of Nitrogen Oxides, Sulfur Dioxide,
and Diluent Emissions from Stationary Gas Turbines”) (40 CFR 60, Appendix A).
504.11 ASTM Method D2622-05, (“Standard Test Method for Sulfur in Petroleum Products
by Wavelength Dispersive X-Ray Fluorescence Spectrometry”).
504.12 ASTM Method D2880-96 (“Standard Specification for Gas Turbine Fuel Oils”).
504.13 ASTM Method D4294-02 or D4294-03, (“Standard Test Method for Sulfur in
Petroleum and Petroleum Products by Energy-Dispersive X-Ray Fluorescence
Spectrometry”).
504.14 ASTM Method D5504-01 or D5504-08, (“Standard Test Method for Determination
of Sulfur compounds in Natural Gas and Gaseous Fuels by Gas Chromatography
and Chemiluminescence”).
504.15 South Coast Air Quality Management District Method 307-91 (“Determination of
Sulfur in a Gaseous Matrix”), revised 1994.
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APPENDIX A TO RULE 323
RACT TUNING PROCEDURES
Nothing in these equipment tuning procedures shall be construed to require any act or omission that
would result in unsafe conditions or would be in violation of any regulation of requirement
established by Factory Mutual, Industrial Risk Insurers, National Fire Prevention Association, the
Industrial Commission of Arizona (Arizona Division of Occupational Safety and Health), the
Federal Occupational Safety and Health Administration, or other relevant regulations and
requirements. Steps in these procedures that are not applicable to specific combustion units may be
omitted.
Tuning Procedure for Forced Draft Fired Boilers, Steam Generating Units, and Process
Heaters:
1. Operate the combustion unit at the firing rate most typical of normal operation. If the
combustion unit experiences significant load variations during normal operation, operate it
at its average firing rate.
2. At this firing rate, record the stack gas temperature, oxygen concentration, and CO
concentration (for gaseous fuels) or smoke-spot number3 (for liquid fuels), and observe
flame conditions after operation stabilizes at the firing rate selected. If the excess oxygen in
the stack gas is at the lower end of the range of typical minimum values4, and if CO
emissions are low and there is no smoke, the combustion unit is probably operating at near
optimum efficiency at this particular firing rate. Complete the remaining steps in this
procedure to determine whether still lower oxygen levels are practical.
3. Increase combustion air flow to the furnace until stack gas oxygen levels increase by one to
two percent over the level measured in Step 2 and record the stack gas temperature, oxygen
concentration, CO concentration (for gaseous fuels) or smoke-spot number (for liquid
fuels), and observe flame conditions for these higher oxygen levels after boiler operation
stabilizes.
4. Decrease combustion air flow until the stack gas oxygen concentration is at the level
measured in Step 2. From this level, gradually reduce the combustion air flow, in small
increments. After each increment, record the stack gas temperature, oxygen concentration,
CO concentration (for gaseous fuels) and smoke-spot number (for liquid fuels). Also
observe the flame and record any changes in its condition.
5. Continue to reduce combustion air flow stepwise, until one of these limits is reached:
a. Unacceptable flame conditions, such as flame impingement on furnace walls or burner
parts, excessive flame carryover, or flame instability;
b. Stack gas CO concentrations greater than 400 ppm;
c. Smoking at the stack; or
3 The smoke-spot number shall be determined with ASTM D2156.
4 Typical minimum oxygen levels for boilers firing at high firing rates are 0.5 – 3% (gaseous fuels) and 2 – 4% (liquid
fuels).
60

d. Equipment related limitations, such as low windbox/furnace pressure differential, built
in air-flow limits, etc.
6. Develop an O2/CO curve (for gaseous fuels) or O2/smoke curve (for liquid fuels) using the
excess oxygen and CO or smoke-spot number data obtained at each combustion air flow
setting.
7. From the O2/CO curve or the O2/smoke curve, find and record the stack gas oxygen levels
where the CO emissions or smoke-spot number equal the following values:
Fuel Measurement Value
Gaseous CO Emissions 400 ppm
#1 & #2 oils Smoke-spot number Number 1
#4 oils Smoke-spot number Number 2
#5 oils Smoke-spot number Number 3
Other oils Smoke-spot number Number 4
8. The stack gas oxygen level recorded in Step 7 is the minimum excess oxygen level (or the
CO/smoke threshold). Compare the minimum excess oxygen level to the expected value
provided by the combustion unit manufacturer. If the minimum level is found to be
substantially higher than the value provided by the combustion unit manufacturer, burner
adjustments can probably be made to improve fuel and air mixing, thereby allowing
operation with less air.
9. Increase the minimum excess oxygen level identified in Step 7 by 0.5 to 2.0 percent and reset
burner controls to operate automatically at this higher stack gas oxygen level. This margin
above minimum oxygen level accounts for fuel variations, variations in atmospheric
conditions, load changes, and nonrepeatability or play in automatic controls.
10. If the load of the combustion unit varies significantly during normal operation, repeat Steps
1 through 8 for firing rates that represent the upper and lower limits of the range of the load.
Because control adjustments at one firing rate may affect conditions at other firing rates, it
may not be possible to establish the optimum excess oxygen level at all firing rates. If this is
the case, choose the burner control settings that give best performance over the range of
firing rates. If one firing rate predominates, settings should optimize conditions at that firing
rate.
11. Verify that the new settings can accommodate the sudden changes that may occur in daily
operation without adverse effects. Do this by increasing and decreasing load rapidly while
observing the flame and stack. If any of the conditions in Step 5 result, reset the combustion
controls to provide a slightly higher level of excess oxygen. Verify the new settings in a
similar manner. The final control settings that reflect combustion optimization shall be
recorded for future reference.
Natural Draft Fired Boilers, Steam Generating Units, and Process Heaters:
1. Verify that the combustion unit is operating at the lowest pressure or temperature setting
that will satisfy load demand. This pressure or temperature will be used as a basis for
comparative combustion analysis before and after tuning.
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2. Verify that the combustion unit will operate for the minimum number of hours necessary to
perform the tuning procedure.
3. Verify that the size of air supply openings is in compliance with applicable codes and
regulations. Air supply openings must be fully open when the burner is firing and air flow
must be unrestricted.
4. Verify that the vent is in good condition, properly sized, and free from obstruction.
5. Perform a combustion analysis at both high and low fire, if possible. Record the following
data for each combustion analysis:
a. The concentration of CO and oxygen;
b. Inlet fuel pressure at burner at high and low firing rates;
c. Steam pressure, water temperature, process fluid temperature, or temperature entering
and leaving the combustion unit; and
d. Inlet fuel use rate, if a meter is available.
6. Clean all dirty burners or burner orifices. Verify that fuel filters and moisture traps are in
place, clean, and operating properly. Confirm proper location and orientation of burner
diffuser spuds, gas canes, etc. Replace or repair damaged or missing burner parts.
7. Remove external and internal sediment and scale from heating surfaces.
8. Verify that the necessary water or process fluid treatment is being used. Confirm flushing
and/or blowdown schedule.
9. Repair all leaks. In addition to the high-pressure lines, check the blow-off, drain, safety valve,
bypass lines, and if used, the feed pump.
10. Perform the following safety checks:
a. Test primary and secondary low water level controls;
b. Check operating and limit pressure and temperature controls;
c. Check pilot safety shut off operation;
d. Check safety valve pressure setting and verify that the setting is consistent with load
requirements; and
e. Check limit safety control and spill switch.
11. Adjust the combustion unit to fire at the maximum inlet fuel use rate; record fuel manifold
pressure.
12. Adjust draft and/or fuel pressure to obtain acceptable, clean combustion at high, medium,
and low firing rates. The CO concentration should not exceed 400 ppm at 3% oxygen.
13. Verify that light-offs are smooth and safe. Perform a reduced fuel pressure test at both high
and low firing rates in accordance with the manufacturer’s instructions.
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14. Check and adjust the modulation controller. Verify proper, efficient, and clean combustion
through the range of firing rates. When optimum performance has been achieved, record all
data.
15. Perform a final combustion analysis on the warm combustion unit at high, medium, and low
firing rates, if possible. Record data obtained from the combustion analysis as well as the
following information:
a. Inlet fuel pressure at burner at high and low firing rates;
b. Pressure above draft hood or barometric damper at high, medium, and low firing rates.
c. Steam pressure, water temperature, or process fluid pressure or temperature entering and
leaving the combustion unit; and
d. Inlet fuel use rate if a meter is available.
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Return to list of attachments
DRAFT NOTICE OF FINAL RULEMAKING
MARICOPA COUNTY AIR POLLUTION CONTROL REGULATIONS
REGULATION III – CONTROL OF AIR CONTAMINANTS
RULE 324: STATIONARY RECIPROCATING INTERNAL
COMBUSTION ENGINES (RICE)
The Maricopa County Air Quality Department (MCAQD) is proposing to amend Rule 324
(Stationary Reciprocating Internal Combustion Engines (RICE)). The Control Officer is posting this
Draft Notice of Final Rulemaking on the Maricopa County Enhanced Regulatory Outreach Program
(EROP) website as part of the Report to the Board of Supervisors, in accordance with the Maricopa
County EROP Policy. This notice includes the preamble, as prescribed in A.R.S. § 49-471.05, and
the full text of the rule, including the intended actions to make new sections or amend, repeal, or
renumber the sections of the rule. This notice also includes a list of all previous notices posted on
the Maricopa County EROP website addressing the proposed rule and the concise explanatory
statement prescribed in A.R.S. § 49-471.07, subsection B.
PREAMBLE
1. Statutory authority for the rulemaking:
A.R.S. §§ 49-112, 49-474, 49-479 and 49-480
2. Name and address of department personnel with whom persons may communicate
regarding the rulemaking:
Name: Scott Kahldon or Kimberly Butler
Maricopa County Air Quality Department
Planning and Analysis Division
Address: 3800 N Central Avenue, Suite 1400
Phoenix, AZ 85012
Telephone: (602) 506-6010
Fax: (602) 506-6179
Email: AQPlanning@maricopa.gov
Submit Comments At: http://maricopa.gov/FormCenter/Regulatory-Outreach-17/Citizen-
Comments-94
3. Rulemaking process:
This rulemaking (AQ-2017-007-Rule 324) is following procedures identified in state statutes
and the Maricopa County EROP Policy:
County Manager Briefing: December 2017
Stakeholder Workshops: August 22, 2018
October 24, 2019
Board of Health Meeting to Initiate Regulatory Change: February 25, 2019
Notice of Proposed Rulemaking: November 24, 2020
64

Return to list of attachments
Board of Health Meeting to Recommend Approval to
the Board of Supervisors: April 26, 2021
Board of Supervisors Formal Meeting to set the
Public Hearing: May 19, 2021
Board of Supervisors Public Hearing: June 23, 2021
4. Explanation of the rule, including the control officer's reasons for initiating the
rulemaking:
Rule 324 (Stationary Reciprocating Internal Combustion Engines [RICE]) limits emissions of
nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), particulate matter
(PM), and volatile organic compounds (VOC) from stationary reciprocating internal
combustion engines (such as electrical generators and mechanical pumps).
The MCAQD is proposing to revise Rule 324 to address rule deficiencies identified by the
U.S. Environmental Protection Agency (EPA) to secure full approval of Rule 324 as a
revision to the Arizona State Implementation Plan (SIP).
On May 4, 2016, portions of Maricopa County were designated as a moderate nonattainment
area with respect to the 2008 National Ambient Air Quality Standards for Ozone. Sections
182(b)(2) and 182(f) of the Clean Air Act require jurisdictions that are classified as
“moderate” or higher nonattainment to implement reasonably available control technology
(RACT) for all categories of VOC sources covered by a Control Technique Guideline
document as well as for all major stationary sources of NOX and VOCs that are located
within the nonattainment area. EPA defines RACT as “the lowest emission limitation that a
particular source is capable of meeting by the application of control technology that is
reasonably available considering technological and economic feasibility”. The EPA provides
guidance on RACT for sources of NOX through Alternative Control Technology (ACT)
documents which offer State and local air pollution control authorities information that
assists in determining NOX-RACT for air quality rules. In addition, the EPA reviews SIP-
approved air quality rules from other air districts with ozone nonattainment areas to assist in
determining NOX-RACT for air quality rules.
In November 2016, Rule 324 was revised to implement RACT for sources of NOX. The
revised rule was submitted to the EPA in June of 2017, as part of the SIP Revision for the
Maricopa County Air Quality Department Ozone Rules contained in the Arizona SIP. The
EPA reviewed Rule 324 and provided the MCAQD with written rule approvability and rule
improvement comments for the rule. EPA staff informed MCAQD staff they would be
using a conditional approval process to act on Rule 324 and the MCAQD would need to
draft a commitment letter outlining revisions to Rule 324 to address the rule approvability
comments.
On January 28, 2019, the MCAQD submitted a Letter of Commitment for Conditional
Approval of the Maricopa County RACT SIP to the EPA. Later, on December 5, 2019, the
MCAQD submitted a supplemental commitment letter to address additional rule
approvability comments MCAQD received after the original commitment letter was
submitted. Based on the commitment letters, the EPA published a proposed conditional
approval of Rule 324 in the Federal Register on December 30, 2019 (Docket ID; EPA-R09-
OAR-2019-0321). The proposed conditional approval rulemaking was available for a 30-day
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comment period, but no comments were received. The proposed conditional approval
references a Technical Support Document (TSD) which includes a thorough review of Rule
324 and MCAQD’s commitments. The TSD outlines EPA’s four (4) official rule
approvability comments (“rule deficiencies”) – which preclude full approval of the rule into
the SIP – as well as four (4) rule revision recommendations, which are not currently the basis
for rule disapproval but are recommended for this current proposed rulemaking for Rule
324. Revisions addressing both the EPA’s identified deficiencies and recommendations have
been made to the proposed draft Rule 324 (included in this notice). A link to EPA’s TSD is
located under Section 5 of this notice.
EPA’s final conditional approval was published on July 20, 2020. The effective date of the
final rule was August 19, 2020. If the MCAQD, through the ADEQ, submits the rule
revisions that the MCAQD has committed to submit within 12 months and the EPA
approves the submission, then the identified deficiencies will be cured, and the rule will be
approved as part of the Arizona SIP.
Details about the EPA’s identified deficiencies and the MCAQD’s proposed remedies are
described below, followed by the EPA rule recommendations and the MCAQD’s proposed
revisions to address the recommendations.
Deficiency 1:
The submitted rule’s current structure of applicability and emission limits does not clearly
outline a RACT limit for NOx and VOC emissions from all applicable IC engines. The
MCAQD should review similar source category regulations in other jurisdictions (San Diego
APCD Rule 69.4 and Yolo-Solano AQMD Rule 2.32) on how they structure clearer RACT
limits that may include similar or more stringent requirements or limits for engines otherwise
subject to federal requirements and standards in 40 CFR part 60, subparts IIII and JJJJ. We
understand that units may need to comply with more stringent Federal standards in some
cases, but a RACT limit would not interfere with a facility’s compliance with a more
stringent limit. The Clean Air Act requires that RACT limitations be approved into the
Federally-enforceable SIP. It is inappropriate to rely on requirements outside of the SIP,
such as NSPS standards found in 40 CFR Part 60.
Remedy 1:
The MCAQD is proposing to restructure the rule to clarify applicability and emission limits.
The MCAQD is proposing to retain existing SIP requirements for stationary RICE that are
not located at a major stationary source of nitrogen oxides. The MCAQD is proposing to
retain the existing numeric emission limits in SIP Rule 324 for non-emergency engines that
are located at a major stationary source of nitrogen oxides (because these limits are
consistent with RACT limits in other jurisdictions).
Deficiency 2:
The submitted rule only applies to engines rated greater than 250 bhp, and to engines greater
than 50 bhp when operating at a facility whose units sum to greater than 250 bhp. The
MCAQD should lower the applicability threshold to 50 bhp to be in line with other
jurisdictions’ RACT rules. The current rule also does not clearly state compliance
requirements for 50 bhp engines summed at a 250 bhp facility.
Remedy 2:
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The MCAQD is proposing to lower the applicability threshold to 50 bhp for stationary
RICE located at a major source of nitrogen oxides. The MCAQD is also proposing to clarify
what emission limits apply to non-emergency engines rated above 50 bhp that are located at
a major stationary source of nitrogen oxides.
Deficiency 3:
The submitted rule allows for flexibility in the treatment of replacement engines. In section
104.6, emergency engines that serve as backup to replace non-emergency engines may do so
until the non-emergency engine is repaired, but this time span is otherwise unbounded, and
may operate above RACT limits. The MCAQD should restrict the amount of time allowed
to operate that emergency engine, or the backup engine should be required to meet RACT
limits. Current rule provisions in sections 207 and 306 also allow for engines that are deemed
equivalent or identical to replace existing engines to be treated the same as the engine being
replaced, but there are no requirements for replacement engines to quantify emissions
equivalency or reductions.
Remedy 3:
The MCAQD is proposing to incorporate constraints on the amount of time an emergency
engine can be used to replace a non-emergency engine when the non-emergency engine has
failed, and to clarify in the definition for “emergency engine” the amount of time that is
allowed for emergency engine operations. The MCAQD is also proposing to remove
provisions related to equivalent replacement engines from Rule 324.
Deficiency 4:
The submitted rule does not specify a compliance determination interval for engines, beyond
at the Control Officer’s discretion. This provision is found in section 501.1b.
Remedy 4:
The MCAQD is proposing to include compliance determination intervals for non-
emergency engines located at both major sources and for those not located at major sources.
Recommendation 1:
Section 103.1(e) exempts stationary engines at a nuclear power plant used for safety reasons.
Please describe the engines used at these facilities and explain why such plants cannot use
compliant engines for safety applications.
Revision 1:
The MCAQD is proposing to change the full exemption to a partial exemption as outlined
under proposed section 108.
Recommendation 2:
Section 104 and section 205 provide special considerations for emergency engines. Please
explain why these engines need special consideration, when these engines already exist on
site. Please characterize the number of sources that have non-compliant engines and would
qualify under these partial exemptions.
Revision 2:
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The MCAQD has reviewed RACT rules for engines in other jurisdictions and determined
that many jurisdictions require maintenance for emergency engines. This is also consistent
with the NSPS and NESHAP for stationary engines (40 CFR 60.4211, 60.4243, and
63.6625(e)). Therefore, the MCAQD is proposing that engine maintenance is RACT for
emergency engines. In addition, MCAQD is also proposing to require an hour meter to
determine compliance with operating limits and fuel records to determine compliance with
fuel requirements.
Recommendation 3:
Section 105 describes a low use threshold that varies between 100-200 hours per year
depending on whether the engine is above or below a 1000 bhp threshold. How many
engines are in each size class, and why is this threshold a reasonable cut-point?
Revision 3:
MCAQD is proposing to limit the partial exemption in Section 105 to those low use non-
emergency engines that are onsite and in use before the date of rule adoption.
Recommendation 4:
Section 103.1.g exempts stationary engines used for training purposes. The term “training” is
undefined. Please define what activities constitute valid training with respect to engines in
this context.
Revision 4:
The MCAQD is proposing to remove this exemption. This exemption has not been used in
the past and training engines that operate less than 100 hours per year may still qualify for
the low-use exemption in Section 105 of this rule.
Additional revisions were made to address stakeholder and staff comments, which can be
discerned in the “strikeout and underline” version of the rule included in this notice and
described in all Stakeholder Workshop notices and workshop slides/presentations that are
posted on the EROP website.
5. Studies relied on in the control officer's evaluation of or justification for the rule and
where the public may obtain or review the studies, all data underlying the studies,
any analysis of the studies and other supporting material.
United States Environmental Protection Agency Region IX Air Division (2019). Technical
Support Document for EPA’s Rulemaking for the Arizona State Implementation Plan
Regarding Rule 324, “Stationary Reciprocating Internal Combustion Engines (RICE).
https://www.regulations.gov/document?D=EPA-R09-OAR-2019-0321-0012
6. An economic, small business and consumer impact statement:
The following discussion addresses each of the elements required for an economic, small
business and consumer impact statement, as prescribed by A.R.S. §§ 41-1055, subsections A,
B and C, and 41-1035:
An identification of the proposed rulemaking, including all of the following:
This rulemaking is proposing to revise Rule 324.
(a) The conduct and its frequency of occurrence that the rule is designed to change.
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The MCAQD is proposing to revise Rule 324 to remedy deficiencies identified by the
EPA. This rulemaking is required to secure approval of Rule 324 into the Arizona SIP.
The revisions are explained in more detail in Item #4 of this notice.
(b) The harm resulting from the conduct the rule is designed to change and the
likelihood it will continue to occur if the rule is not changed.
The MCAQD is proposing to revise Rule 324 to remedy deficiencies identified by the
EPA. This rulemaking is required to secure approval of Rule 324 into the Arizona SIP
and avoid sanctions and imposition of a Federal Implementation Plan (FIP) under the
Clean Air Act.
(c) The estimated change in frequency of the targeted conduct expected from the
rule change.
The MCAQD is proposing to revise Rule 324 to remedy deficiencies identified by the
EPA. This rulemaking is required to secure approval of Rule 324 into the Arizona SIP.
As with other rules, the MCAQD will use education, outreach, and other compliance
assurance tools to increase the number of people in compliance with the revised rule.
The MCAQD strives to achieve the highest possible compliance rates.
A brief summary of the information included in the economic, small business and
consumer impact statement.
The economic, small business and consumer impact statement addresses each of the
elements required for an economic, small business and consumer impact statement, as
prescribed by A.R.S. §§ 41-1055, subsections A, B, and C, and 41-1035.
Name and address of agency employees who may be contacted to submit or request
additional data on the information included in the economic, small business and
consumer impact statement.
Name: Scott Kahldon or Kimberly Butler
Maricopa County Air Quality Department
Planning and Analysis Division
Address: 3800 N Central Avenue, Suite 1400
Phoenix, AZ 85012
Telephone: (602) 506-6010
Fax: (602) 506-6179
Email: AQPlanning@maricopa.gov
Submit Comments At: http://maricopa.gov/FormCenter/Regulatory-Outreach-17/Citizen-
Comments-94
An identification of the persons who will be directly affected by, bear the costs of or
directly benefit from the proposed rulemaking.
This rulemaking will directly affect facilities in Maricopa County that have stationary
reciprocating internal combustion engines with a rated brake horsepower (rated bhp) of:
(1) Greater than 125, if the stationary RICE is not located at a major source of NOx
emissions,
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(2) Greater than 50, if the stationary RICE is not located at a major source of NOx
emissions and the maximum aggregated rated bhp of all stationary RICE at the
stationary source is more than 125 when all engines with a rated bhp of more than 50 are
aggregated,
(3) Greater than 50, if the stationary RICE is located at a major source of NOx emissions,
and
(4) Any nonroad engine, with a rated bhp of greater than 125, that is located at a stationary
source that emits or has the potential to emit any regulated air pollutant greater than the
permitting thresholds defined in Rule 100.
A cost benefit analysis of the following:
(a) The probable costs and benefits to the implementing agency and other agencies
directly affected by the implementation and enforcement of the proposed
rulemaking.
This rulemaking should not impose any new costs on the MCAQD or on any other
agencies affected by the proposed rulemaking.
(b) The probable costs and benefits to a political subdivision of this state directly
affected by the implementation and enforcement of the proposed rulemaking.
The MCAQD is proposing to revise Rule 324 to remedy deficiencies identified by the
EPA. This rulemaking is required to secure approval of Rule 324 into the Arizona SIP
for RACT and avoid sanctions and imposition of a FIP under the Clean Air Act. In
general, the majority of political subdivisions to which this rule applies will not incur
significant new costs based on the proposed revisions; however, some political
subdivisions may incur costs required to comply with the revised compliance
determination methods in Section 500, specifically the revised performance test
requirements. In current Rule 324, a political subdivision required to conduct a
performance test to demonstrate compliance under Section 500 must do so upon request
by the Control Officer. Under Section 500 in the proposed rule, a political subdivision
required to conduct a performance test to demonstrate compliance will have to do so at
least once every 5 years. For some political subdivisions, this may require new or
additional performance testing which will lead to increased costs. In addition, new or
additional performance testing may lead to increased cases of noncompliance, and for
those political subdivisions that are out of compliance, there will be increased costs to
come back into compliance.
(c) The probable costs and benefits to businesses directly affected by the proposed
rulemaking, including any anticipated effect on the revenues or payroll
expenditures of employers who are subject to the proposed rulemaking.
The MCAQD is proposing to revise Rule 324 to remedy deficiencies identified by the
EPA. This rulemaking is required to secure approval of Rule 324 into the Arizona SIP
for RACT and avoid sanctions and imposition of a FIP under the Clean Air Act. In
general, the majority of businesses to which this rule applies will not incur significant
new costs based on the proposed revisions; however, some businesses may incur costs
required to comply with the revised compliance determination methods in Section 500,
specifically the revised performance test requirements. In current Rule 324, a business
required to conduct a performance test to demonstrate compliance under Section 500
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must do so upon request by the Control Officer. Under Section 500 in the proposed
rule, a business required to conduct a performance test to demonstrate compliance will
have to do so at least once every 5 years. For some businesses, this may require new or
additional performance testing which will lead to increased costs. In addition, new or
additional performance testing may lead to increased cases of noncompliance, and for
those businesses that are out of compliance, there will be increased costs to come back
into compliance.
A general description of the probable impact on private and public employment in
businesses, agencies and political subdivisions of this state directly affected by the
proposed rulemaking.
This rulemaking should not have a significant impact on private or public employment in
businesses, agencies, and political subdivisions of this state.
A statement of the probable impact of the proposed rulemaking on small businesses.
The statement shall include:
(a) An identification of the small businesses subject to the proposed rulemaking.
Small businesses subject to this rulemaking are those facilities in Maricopa County that
have stationary reciprocating internal combustion engines that meet the requirements of
Section 102 of the draft rule included in this notice.
(b) The administrative and other costs required for compliance with the proposed
rulemaking.
In general, the majority of businesses to which this rule applies will not incur significant
new costs based on the proposed revisions; however, some businesses may incur costs
required to comply with the revised compliance determination methods in Section 500,
specifically the revised performance test requirements. In current Rule 324, a business
required to conduct a performance test to demonstrate compliance under Section 500
must do so upon request by the Control Officer. Under Section 500 in the proposed
rule, a business required to conduct a performance test to demonstrate compliance will
have to do so at least once every 5 years. For some businesses, this may require new or
additional performance testing which will lead to increased costs. In addition, new or
additional performance testing may lead to increased cases of noncompliance, and for
those businesses that are out of compliance, there will be increased costs to come back
into compliance.
(c) A description of the methods that the agency may use to reduce the impact on
small businesses.
i. Establish less stringent compliance or reporting requirements in the rule for
small businesses.
In general, this rulemaking does not impose any significant new compliance
requirements on small businesses and does not establish any significant new
reporting requirements for small businesses. However, some small businesses will be
required to comply with the revised compliance determination methods in Section
500, specifically the revised performance test requirements described above. For
some small businesses, this may require new or additional performance testing. Less
stringent performance testing requirements are not feasible because the revised
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testing requirements are required to remedy one of the deficiencies identified by the
EPA in the rule.
ii. Establish less stringent schedules or deadlines in the rule for compliance or
reporting requirements for small businesses.
In general, this rulemaking does not impose any significant new schedules or
deadlines for compliance and reporting requirements on small businesses. However,
some small businesses will be required to comply with the revised compliance
determination methods in Section 500, specifically the revised performance test
requirements described above. For some small businesses, this may require new or
additional performance testing. Less stringent performance testing requirements are
not feasible because the revised testing requirements are required to remedy one of
the deficiencies identified by the EPA in the rule.
iii. Consolidate or simplify the rule's compliance or reporting requirements for
small businesses.
In general, this rulemaking does not impose any significant new compliance
requirements on small businesses and does not establish any significant new
reporting requirements for small businesses. However, some small businesses will be
required to comply with the revised compliance determination methods in Section
500, specifically the revised performance test requirements described above. For
some small businesses, this may require new or additional performance testing. Less
stringent performance testing requirements are not feasible because the revised
testing requirements are required to remedy one of the deficiencies identified by the
EPA in the rule.
iv. Establish performance standards for small businesses to replace design or
operational standards in the rule.
In general, this rulemaking does not impose any significant new compliance
requirements on small businesses and does not establish any significant new
reporting requirements for small businesses. However, some small businesses will be
required to comply with the revised compliance determination methods in Section
500, specifically the revised performance test requirements described above. For
some small businesses, this may require new or additional performance testing. Less
stringent performance testing requirements are not feasible because the revised
testing requirements are required to remedy one of the deficiencies identified by the
EPA in the rule.
v. Exempt small businesses from any or all requirements of the rule.
This rulemaking contains some partial and full exemptions as outlined in sections
103-108 within this rule.
(d) The probable cost and benefit to private persons and consumers who are directly
affected by the proposed rulemaking.
This rulemaking should not result in any significant costs for private persons and
consumers.
A statement of the probable effect on state revenues.
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No significant effect on state revenues is expected by this rulemaking.
A description of any less intrusive or less costly alternative methods of achieving the
purpose of the proposed rulemaking, including the monetizing of the costs and
benefits for each option and providing the rationale for not using nonelected
alternatives.
The purpose of this rulemaking is to revise Rule 324 to remedy deficiencies identified by the
EPA. This rule making is required to secure approval of Rule 324 into the State
Implementation Plan (SIP) for RACT and avoid sanctions and imposition of a Federal
Implementation Plan (FIP) under the Clean Air Act.
A description of any data on which a rule is based with a detailed explanation of how
the data was obtained and why the data is acceptable data.
Not applicable.
7. The proposed effective date of the rule:
The proposed effective date of this rulemaking is June 23, 2021.
8. Such other matters as are prescribed by statute and that are applicable to the county
or to any specific rule or class of rules:
Under A.R.S. § 49-479(C), a county may not adopt a rule or ordinance that is more stringent
than the rules adopted by the Director of the Arizona Department of Environmental Quality
(ADEQ) for similar sources unless it demonstrates compliance with the applicable
requirements of A.R.S. §49-112.
§ 49-112 County regulation; standards
§ 49-112(A)
When authorized by law, a county may adopt a rule, ordinance or regulation that is more
stringent than or in addition to a provision of this title or rule adopted by the director or any
board or commission authorized to adopt rules pursuant to this title if all of the following
requirements are met:
1. The rule, ordinance or regulation is necessary to address a peculiar local condition.
2. There is credible evidence that the rule, ordinance or regulation is either;
(a) Necessary to prevent a significant threat to public health or the environment that
results from a peculiar local condition and is technically and economically feasible.
(b) Required under a federal statute or regulation or authorized pursuant to an
intergovernmental agreement with the federal government to enforce federal statutes
or regulations if the county rule, ordinance or regulation is equivalent to federal
statutes or regulation.
3. Any fee or tax adopted under the rule, ordinance or regulation does not exceed the
reasonable costs of the county to issue and administer the permit or plan approval
program.
§ 49-112(B)
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When authorized by law, a county may adopt rules, ordinances or regulations in lieu of a
state program that are as stringent as a provision of this title or rule adopted by the director
or any board or commission authorized to adopt rules pursuant to this title if the county
demonstrates that the cost of obtaining permits or other approvals from the county will
approximately equal or be less than the fee or cost of obtaining similar permits or approvals
under this title or any rule adopted pursuant to this title. If the state has not adopted a fee or
tax for similar permits or approvals, the county may adopt a fee when authorized by law in
the rule, ordinance or regulation that does not exceed the reasonable costs of the county to
issue and administer that permit or plan approval program.
The department is in compliance with A.R.S. §§ 49-112 (A) and (B). Rule 324 meets A.R.S. §
49-112 (A) (1) by demonstrating that the rule is necessary to address a peculiar local
condition, in that Maricopa County fails to meet the 8-hour NAAQS for ozone. Rule 324
meets the requirements of A.R.S. § 49-112 (A) (2) (b), in that Maricopa County is required by
federal law to revise existing rules to address RACT for the facilities that have stationary
reciprocating internal combustion engines. As there is no new fee or tax associated with this
proposed rulemaking, the department also affirms that Rule 324 meets the requirements of
A.R.S. § 49-112 (A) (3) and A.R.S. § 49-112 (B).
9. List of all previous notices posted to the Maricopa County EROP website addressing
the proposed rule and a concise explanatory statement, as prescribed by A.R.S. § 49-
471.07, subsection B:
(a) List of all previous notices posted to the Maricopa County EROP website
addressing the proposed rule:
Notice Date of Posting
Briefing Notification to County Manager: January 26, 2018
Notice of Stakeholder Workshop: August 03, 2018
October 09, 2019
Notice of Board of Health Meeting to Initiate
Regulatory Change: February 08, 2019
Notice of Proposed Rulemaking: November 24, 2020
Notice of Board of Health Meeting to Make
Recommendations to the Board of Supervisors: April 12, 2021
(b) The following discussion addresses each of the elements required for a concise
explanatory statement, as prescribed by A.R.S. § 49-471.07, subsection B:
i. A description of any change between the proposed rule or ordinance, the final
rule or ordinance or notice of final supplemental rule or ordinance.
The following changes were made after the Notice of Proposed Rulemaking was
published on November 24, 2020.
1. The MCAQD revised the definition of Part(s) Per Million, Dry Volume
(PPMDV) to be consistent between Rules 322, 323, and 324. The section was
revised as indicated below:
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Section 215: PARTS PER MILLION BY VOLUME DRY (PPMVD): A unit
of proportion used to express concentration that is corrected to a dry basis.
2. Based off of staff comments, the MCAQD removed the oxygen correction from
the definition of Part(s) Per Million, Dry Volume and placed it closer to the
corresponding emission limits in the rule to improve rule clarity. The MCAQD
added an asterisk to denote the phrase “ppmvd emission standards are corrected
to 15% oxygen” to the tables indicated below:
Table 324-1
Table 324-2
Table 324-3
3. The MCAQD revised the acronym “ppmdv” to “ppmvd” to match the revised
definition for Parts Per Million By Volume Dry (PPMVD). This revision was
added to the tables listed below.
Table 324-1
Table 324-2
Table 324-3
4. The MCAQD removed the language “in accordance with the requirements of
Rule 270 of these rules” in section 501.4. The section was revised as indicated
below:
Section 501.4: Performance Test Conditions: Performance tests shall be
conducted using the test methods listed in Section 503 of this rule. Testing for
stationary RICE shall be completed at either the maximum operating load or
no less than 80% of the rated bhp. If the owner or operator of an engine
demonstrates to the Control Officer that the engine cannot operate at these
conditions, then emissions source testing shall be performed at the highest
achievable continuous rated bhp or under the typical duty cycle or typical
operational mode of the engine. The result of the performance test shall be
the arithmetic mean of the results of three test runs. Each test run shall have a
minimum sample time of one hour.
5. Based off of stakeholder comments, the MCAQD revised the applicability
language in Section 102.1.d to clarify which nonroad engines are subject to the
recordkeeping requirements in Rule 324. This section was revised as indicated
below:
Section 102.1.d: Any nonroad engine, with a rated bhp of greater than 125,
that is located at a stationary source that emits or has the potential to emit any
regulated air pollutant greater than the permitting thresholds defined in Rule
100 of these rules. For the purpose of this Rule, a nonroad engine is any
internal combustion engine that by itself or in or on a piece of equipment is
portable or transportable, meaning designed to be and capable of being
carried or moved from one location to another. Indicia of transportability
include but are not limited to, wheels, skids, carrying handles, dollies, trailers,
or platforms.
In addition, the MCAQD revised the nonroad engine records requirements in
Section 502.6 to clarify the records specified in Section 502.6.b.(1), (2) and (3) are
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only required to be kept for those nonroad engines located at a stationary source
greater than 14 consecutive days. This section was revised as indicated below:
Section 502.6: Nonroad Engine Records: An owner or operator of a nonroad
engine shall maintain the following records for each non-road engine:
a. Date that each engine is brought to the stationary source; and
b. For engines located at a stationary source greater than 14 consecutive
days:
(1) Make, model, serial number, and rated capacity (bhp hours) of the
engine; and
(2) Date of each instance in which the engine is moved from its
existing location, and the reason why the engine was moved; and
(3) Fuel type and sulfur content of the fuel. Return to list of attachments
ii. A summary of the comments and arguments for and against the notice and the
county’s response to the comments and arguments.
The following discussion evaluates the arguments for and against the rule and
includes responses to comments received on the proposed rule or the preamble in the
Notice of Proposed Rulemaking. The MCAQD received written comments from four
(4) stakeholders. All of the comments were reviewed and evaluated by the MCAQD.
Comment #1: The hours of operation for emergencies should be specified in this
section and testing, reliability and maintenance hours should be grouped together as
non-emergency hours. Suggested language is: “Monthly and rolling twelve-month
total hours of operation, emergency hours of operation, and non-emergency hours of
operation (including hours for testing, reliability, and maintenance).”
Response #1: The MCAQD considered your comment and revised the language in
Section 502.2 to read as follows: Operation Records: An owner or operator of a
stationary RICE shall maintain records of the monthly and 12-month rolling total
hours of operation for each stationary RICE. For emergency engines, the operation
records shall also include:
a. Monthly and annual hours of operation for reliability related activities such as
engine readiness, calibration, or maintenance, or to prevent the occurrence of an
unsafe condition during electrical system maintenance; and
b. The number of operating hours for emergency use and an explanation for the
emergency use.
Comment #2: We recently had several air permit inspections for our general permits
that are for our emergency generators. We have been having these inspections every
other year for our facilities and not had any major issues during the inspections. Each
generator has a logbook that has a monthly record for the checks that take place, any
operation or other issues that occur. Historically, these records were used to calculate
the 12-month hours of operation to show compliance with permit conditions.
However, during our recent inspections, we were informed that we had not been
keeping a monthly rolling record of hours and that we needed to begin this for our
general permitted sites. I've reviewed the permit and Rule 324 and understand that
this is required but seems like an unnecessary effort if we keep a monthly log of
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hours. The previous 12 months can easily be calculated by taking March 2019 hours
and subtracting March 2018 hours to show the current 12 months of hours of
operation. The City of Chandler emergency generators typically run less than a couple
hours a month, often times even less than a couple hours. The City understands the
permit language and will do what is needed to maintain compliance. However, since
our sites have been inspected frequently and this has not previously been noted nor
has it been noted as a compliance issue. The City believes that for remote sites that
also run very limited hours that the information needed to determine hours of
operation can be calculated from the on-site logbooks during inspections. Our
emergency generators are typically at unmanned facilities, have limited use and would
require additional effort and resources to collect and track this information. We hope
to see this requirement addressed through logbook information that is maintained at
each site and not a requirement to create spreadsheets for each generator (we have
over 30 permitted sites). Since Rule 324 is currently being reviewed and possibly
amended we hope that this issue can be addressed during this process. We would like
to see this section clarified that for limited use, unmanned sites that the on-site
logbook can be used to determine the 12-month hours of operation.
Response #2: The MCAQD considered your comment and determined that records
of the 12-month rolling total hours of operation are needed to ensure compliance
with emission and/or operation limits. The information can be recorded in the
logbook or using any other method as long as the required records are maintained.
Comment #3: We have reviewed the language and our operations across our fleet.
We are requesting the following change to the verbiage (see below). We have engines
from 15 different manufactures (some are no longer in business) and only use a single
qualified service provider. The use of one contractor to conduct engine is preferred
by our Supply Chain because of the clearance required to work at some of our sites as
well as safety hazards associated with our facilities. There are some service providers
that have safety records that prohibit them from working at our sites entirely.
An owner or operator of a stationary RICE shall maintain the stationary RICE in
accordance with the manufacturer's written instructions or in accordance with the
written maintenance schedule provided by the manufacturer’s authorized a qualified
service provider. If the manufacturer's written instructions are not available and the
manufacturer’s authorized qualified service provider does not provide a written
maintenance schedule, the owner or operator shall conduct preventative maintenance
according to the following schedule, including all of the following procedures, if the
engine is so equipped, and if such procedures are appropriate to the type of engine:
Response #3: The MCAQD considered your comment and revised the language in
Section 302 to read as follows: MAINTENANCE REQUIREMENTS: An owner or
operator of a stationary RICE shall maintain the stationary RICE in accordance with
the manufacturer's written instructions or in accordance with the maintenance
schedule provided by the manufacturer’s authorized service provider. Alternatively,
the owner or operator shall conduct preventative maintenance according to the
following schedule, including all of the following tuning procedures, if the engine is so
equipped, and if such procedures are appropriate to the type of engine.
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Comment #4: Thanks for the opportunity to provide comments in your chat room
during the October 24, 2019 workshop. I notice of you could not accept a proposed
comment [KB-A30] about changing the term “manufacturer’s authorized service
provider” with the term “qualified service provider” because this is not a recognized
term in use by the EPA. We agree with the commenters concern about the term
“authorized service provider” because the term in our opinion raises proprietary
issues related to maintenance documentation provided by engine and/or emergency
generator manufacturers exclusively to authorized dealerships. A regular maintenance
provider may have authorizations from various engine manufacturers but may not be
able to get authorizations from for example emergency generator manufacturers who
have their own non-road engines installed. We suggest you consider alterative options
and include language in Section 302 about “or authorization from a manufacturer of a
similar engine type” and “in accordance with recommendations from the
manufacturer of a similar engine type.”
Response #4: The MCAQD considered your comment and revised the language in
Section 302 to read as follows: MAINTENANCE REQUIREMENTS: An owner or
operator of a stationary RICE shall maintain the stationary RICE in accordance with
the manufacturer's written instructions or in accordance with the maintenance
schedule provided by the manufacturer’s authorized service provider. Alternatively,
the owner or operator shall conduct preventative maintenance according to the
following schedule, including all of the following tuning procedures, if the engine is so
equipped, and if such procedures are appropriate to the type of engine.
Comment #5: I have a few comments for draft Rule 324, which deals explicitly with
non-road engines. I understand the purpose of tracking non-road engines and the
amount of time they are onsite to ensure there is no circumvention of the rules by
using a non-road engine as a stationary engine. Unfortunately, the record-keeping
requirement can be quite burdensome for facilities with special events that use non-
road generators for a minimal amount of time. Almost all non-road generators are
brought onto the site and removed in less than a week, and many within 24 hours.
Could there be a timeframe, such as seven days, that if a non-road engine is brought
onsite for more than seven days, then section 502.6 applies? Additionally, the serial
number requirement in Section 502.6 b. can be difficult to obtain depending on the
situation. Rental companies will have the make, model, and capacity readily available
for the non-road engines being rented, but not the specific serial number sent to the
site. If the non-road engine is brought onto the site for a single night event, it can be
challenging to obtain the serial number for an event that lasts three hours at night.
Response #5: The MCAQD considered your comments and revised the language in
Section 502.6 to read as follows: Nonroad Engine Records: An owner or operator of
a nonroad engine shall maintain the following records for each non-road engine: a.
Date that each engine is brought to the stationary source ; and b. For engines located
at a stationary source greater than 14 consecutive days: (1) Make, model, serial
number, and rated capacity (bhp hours) of the engine; and (2) Date of each instance
in which the engine is moved from its existing location, and the reason why the
engine was moved; and (3) Fuel type and sulfur content of the fuel. Additionally, the
MCAQD revised the applicability language in Section 102.1.d to clarify which
nonroad engines are subject to the recordkeeping requirements in Rule 324. Section
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102.1.d now reads as follows: Any nonroad engine, with a rated bhp of greater than
125, that is located at a stationary source that emits or has the potential to emit any
regulated air pollutant greater than the permitting thresholds defined in Rule 100 of
these rules. For the purpose of this Rule, a nonroad engine is any internal combustion
engine that by itself or in or on a piece of equipment is portable or transportable,
meaning designed to be and capable of being carried or moved from one location to
another. Indicia of transportability include but are not limited to, wheels, skids,
carrying handles, dollies, trailers, or platforms.
Return to list of attachments
EXACT WORDING OF THE RULE
MARICOPA COUNTY
AIR POLLUTION CONTROL REGULATIONS
REGULATION III - CONTROL OF AIR CONTAMINANTS
RULE 324
STATIONARY RECIPROCATING INTERNAL COMBUSTION ENGINES (RICE)
INDEX
SECTION 100 – GENERAL
101 PURPOSE
102 APPLICABILITY
103 EXEMPTIONS
104 PARTIAL EXEMPTIONS FOR EMERGENCY ENGINES
105 PARTIAL EXEMPTIONS FOR LOW USAGE NON-EMERGENCY ENGINES
106 PARTIAL EXEMPTION FOR NON-EMERGENCY ENGINES SUBJECT TO
40 CFR PART 63, SUBPART ZZZZ NONROAD ENGINES
107 PARTIAL EXEMPTION FOR NON-EMERGENCY ENGINES THAT ARE
LOCATED AT A MAJOR SOURCE OF NITROGEN OXIDES (NOX)
108 PARTIAL EXEMPTION FOR STATIONARY RICE THAT ARE LOCATED
AT A NUCLEAR POWER PLANT
SECTION 200 – DEFINITIONS
201 AFTERCOOLER/INTERCOOLER
202 ALTERNATIVE FUELS
202 203 COGENERATION UNIT
204 COMMISSIONING PERIOD
203 205 COMPRESSION-IGNITION ENGINE
204 DIESEL ENGINE
205 206 EMERGENCY ENGINE
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206 ENGINE FAMILY
207 EQUIVALENT REPLACEMENT ENGINE
207 GASOLINE
208 IDENTICAL REPLACEMENT ENGINE
209 LEAN-BURN ENGINE
210 LIQUEFIED PETROLEUM GAS (LPG)
210 211 LOCATION
212 LOW SULFUR OIL
213 NATURAL GAS
211 214 NON-EMERGENCY ENGINE
212 NONROAD INTERNAL COMBUSTION (IC) ENGINE
213 215 PARTS(S) PER MILLION, DRY BY VOLUME DRY (PPMDVD)
214 216 RATED BRAKE HORSEPOWER (RATED BHP)
217 RECONSTRUCTED
215 218 RICH-BURN ENGINE
216 219 SPARK-IGNITION ENGINE
217 220 STATIONARY RECIPROCATING INTERNAL COMBUSTION ENGINE
(RICE)
218 221 SULFUR OXIDES (SOX)
219 222 ULTRA LOW SULFUR OIL DIESEL
220 223 WASTE DERIVED FUEL GAS
SECTION 300 – STANDARDS
301 LIMITATIONS FOR STATIONARY RICE – FUEL REQUIREMENTS
302 GOOD COMBUSTION PRACTICES/TUNING PROCEDURES FOR
STATIONARY RICE MAINTENANCE REQUIREMENTS
303 LIMITATIONS FOR STATIONARY RICE - OPACITY
304 LIMITATIONS FOR NON-EMERGENCY ENGINES - 250 RATED BHP OR
GREATER
305 EFFICIENCY ALLOWANCE
306 305 EQUIVALENT REPLACEMENT ENGINE OR IDENTICAL
REPLACEMENT ENGINE
307 MODIFICATION TO A STATIONARY RICE
308 306 NON-RESETTING TOTALIZING HOUR METER
SECTION 400 – ADMINISTRATIVE REQUIREMENTS
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401 COMPLIANCE SCHEDULE-STATIONARY RICE BEING REMOVED FROM
SERVICE
402 COMPLIANCE SCHEDULE-NON-RESETTING TOTALIZING HOUR
METER
403 COMPLIANCE SCHEDULE-ENGINES AT A SOURCE THAT BECOMES A
MAJOR SOURCE
SECTION 500 – MONITORING AND RECORDS
501 COMPLIANCE DETERMINATION
502 RECORDKEEPING/RECORDS RETENTION
503 COMPLIANCE DETERMINATION-TEST METHODS INCORPORATED BY
REFERENCE
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Adopted 10/22/2003; Revised 10/17/2007; Revised 11/02/2016; Revised MM/DD/YYYY
MARICOPA COUNTY
AIR POLLUTION CONTROL REGULATIONS
REGULATION III – CONTROL OF AIR CONTAMINANTS
RULE 324
STATIONARY RECIPROCATING INTERNAL COMBUSTION ENGINES (RICE)
SECTION 100 – GENERAL
101 PURPOSE: To limit carbon monoxide (CO), nitrogen oxides (NOX), sulfur oxides (SOX),
volatile organic compounds (VOCs), and particulate matter (PM) emissions from stationary
reciprocating internal combustion engines (RICE).
102 APPLICABILITY:
102.1 This rule applies to: a spark-ignition engine or compression-ignition engine including
stationary RICE used in cogeneration, with a rated brake horsepower (rated bhp) of
greater than 250. This rule also applies to a combination of stationary RICE each
with a rated bhp greater than 50 used at a source, whose maximum aggregate rated
bhp is greater than 250.
a. Any stationary RICE, including stationary RICE used in cogeneration, with a
rated brake horsepower (rated bhp) of greater than 125, if the stationary RICE is
not located at a major source of NOX emissions;
b. Any stationary RICE, including stationary RICE used in cogeneration, with a
rated bhp of more than 50 if the stationary RICE is not located at a major source
of NOX emissions and the maximum aggregated rated bhp of all stationary RICE
at the stationary source is more than 125 when all engines with a rated bhp of
more than 50 are aggregated;
c. Any stationary RICE, including stationary RICE used in cogeneration, with a
rated brake horsepower (rated bhp) of greater than 50, if the stationary RICE is
located at a major source of NOX emissions; and
d. Any nonroad engine, with a rated bhp of greater than 125, that is located at a
stationary source that emits or has the potential to emit any regulated air
pollutant greater than the permitting thresholds defined in Rule 100 of these
rules. For the purpose of this Rule, a nonroad engine is any internal combustion
engine that by itself or in or on a piece of equipment is portable or transportable,
meaning designed to be and capable of being carried or moved from one
location to another. Indicia of transportability include but are not limited to,
wheels, skids, carrying handles, dollies, trailers, or platforms.
102.2 NSPS: In addition to this rule, a stationary RICE may be subject to New Source
Performance Standards (NSPS) in Rule 360 of these rules. A stationary RICE subject
to this rule that is also subject to the federal standards of performance set forth in 40
CFR Part 60, Subpart IIII for compression-ignition engines or 40 CFR Part 60,
Subpart JJJJ for spark-ignition engines shall comply with the most stringent
82

requirements. Whenever more than one provision in this rule applies to such engine
or whenever a provision in this rule and a provision in the federal standards apply to
such engine, the provision or combination of provisions resulting in the lowest rate
of emissions shall apply, unless otherwise specifically exempted or designated.
102.3 NSPS & NESHAP: In addition to this rule, a stationary RICE may be subject to
New Source Performance Standards (NSPS) in Rule 360 and/or National Emission
Standards for Hazardous Air Pollutants (NESHAP) in Rule 370 of these rules.
Whenever more than one provision in this rule applies to such engine or whenever a
provision in this rule and a provision in the federal standards apply to such engine,
the provision or combination of provisions resulting in the lowest rate of emissions
shall apply, unless otherwise specifically exempted or designated.
103.1 103 EXEMPTIONS: The following types of stationary RICE are exempt from all of the
requirements of this rule but shall comply with Rule 300 (Visible Emissions) of these rules:
a. A rotary engine, including gas turbines, jet engines.
b. 103.1 A stationary RICE used directly and exclusively for engine research including engine
development, and subsequent engine performance verification for the purpose of
either engine emission control techniques or engine efficiency improvements.
c. 103.2 A non-emergency engine when it is operated for purposes of performance
verification and testing by the owner or operator or by a manufacturer or distributor
of such equipment for the purpose of performance verification and testing at the
production facility.
d. 103.3 A compressed gas stationary RICE used for solar testing and research programs.
e. A stationary RICE operated as an emergency engine or other equipment at a nuclear
power plant that must run for safety reasons and/or operational tests to meet
requirements imposed by the Nuclear Regulatory Commission.
f. 103.4 A stationary RICE test stand used for evaluating engine performance.
g. A stationary RICE used for training purposes as long as the total number of hours of
the operation does not exceed 100 hours per calendar year per engine.
104 PARTIAL EXEMPTIONS FOR EMERGENCY ENGINES: A stationary RICE
operated as an emergency engine, as defined in this rule, for any of the following reasons
shall comply only with the provisions in Sections 301, 303, 306, 307, 400, 502.1 and 502.4 be
exempt from Sections 304, 501.1, 501.2, 501.3, and 501.4 of this rule when:
104.1 Used only for power when normal power service fails from the serving utility or if
onsite electrical transmission or onsite power generation equipment fails.
104.2 Used only for the emergency pumping of water resulting from a flood, fire, lightning
strikes, police action or for any other essential public services which affect public
health and safety.
104.3 Used for lighting airport runways.
104.4 Used for sewage overflow mitigation and/or prevention.
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104.5 Used for reliability-related activities such as engine readiness, calibration, or
maintenance or to prevent the occurrence of an unsafe condition during electrical
system maintenance, as long as the total number of hours of the operation for these
purposes does not exceed 100 hours per calendar year per engine as evidenced by an
installed non-resettable non-resetting totalizing hour meter. For the purposes of this
rule, hours of operation during the commissioning period do not count towards the
100 hour per calendar year limit on hours of operation for reliability-related activities.
104.6 Used as the non-emergency engine when the non-emergency engine has failed, but
only for such time as is needed to repair the non-emergency engine. For the purposes
of this exemption, if the non-emergency engine is not repaired and returned to service
within 12 months, or if the emergency engine is used as the non-emergency engine for
more than 50 hours, whichever occurs first, the emergency engine shall be reclassified
as a non-emergency engine and shall comply with all requirements of this rule that are
applicable to non-emergency engines.
104.7 Used to operate standby emergency water pumps for fire control that activate when
sensors detect low water pressure.
105 PARTIAL EXEMPTIONS FOR LOW USAGE NON-EMERGENCY ENGINES:
The following low usage non-emergency engines onsite and in use before [date of rule
adoption] shall comply only with the provisions in Sections 301, 303, 306, 307, 400, 502.1 and
502.4 be exempt from Sections 304, 501.1, 501.2, 501.3, 501.4, and 502.6 of this rule for:
105.1 Each engine with a rated bhp at or below 1000 that operates less than 200 hours per
calendar year as evidenced by an installed non-resettable non-resetting totalizing hour
meter.
105.2 Each engine with a rated bhp above 1000 that operates less than 100 hours per
calendar year as evidenced by an installed non-resettable non-resetting totalizing hour
meter.
106 PARTIAL EXEMPTION FOR NON-EMERGENCY ENGINES SUBJECT TO 40 CFR
PART 63, SUBPART ZZZZ NONROAD ENGINES: A stationary RICE subject to the
federal standards of performance set forth in 40 CFR Part 63, Subpart ZZZZ shall comply
only with the provisions in Sections 502.1, 502.2, and 502.3 of this rule. Each nonroad
engine shall comply with Rule 300 of these rules and Section 502.6 of this rule, but shall be
exempt from all other requirements of this rule.
107 PARTIAL EXEMPTION FOR NON-EMERGENCY ENGINES THAT ARE
LOCATED AT A MAJOR SOURCE OF NOX: A non-emergency engine that is located at
a major source of NOX shall not be required to comply with Section 501.2 of this rule during
the five year period beginning on January 1st of the year in which the engine was manufactured,
if the owner or operator provides documentation that the non-emergency engine is certified
by the manufacturer to comply with emission limits in 40 CFR 60 subpart IIII or 40 CFR 60
subpart JJJJ that are more stringent than the applicable emission limit(s) in Table 324-3 of
this rule, and provides documentation that the non-emergency engine is installed, operated,
and maintained in accordance with the manufacturer's specifications.
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108 PARTIAL EXEMPTION FOR STATIONARY RICE THAT ARE LOCATED AT
A NUCLEAR POWER PLANT: A stationary RICE that is located at a nuclear power
plant and is operated solely for the following reasons shall comply only with the provisions
in Sections 301, 302, 306, 402, 501.5, 502.1, 502.3, 502.4, and 502.5 of this rule:
108.1 Used for safety reasons and for operational tests required by the Nuclear Regulatory
Commission.
108.2 Used for power when normal power service fails from the serving utility or if onsite
electrical transmission or onsite power generation equipment fails.
108.3 Used for the emergency pumping of water resulting from a flood, fire, lightning
strikes, police action or for any other operation that is essential to public health and
safety.
108.4 Used to initiate operation of onsite emergency power generation equipment.
108.5 Used for reliability-related activities such as engine readiness, calibration, or
maintenance or to prevent the occurrence of an unsafe condition during electrical
system maintenance. Hours of operation for reliability-related activities shall not
exceed 100 hours per year unless the reliability-related activities are recommended or
required by the federal, state, or local government and the owner or operator maintains
records demonstrating that the reliability-related activities are recommended or
required.
SECTION 200 – DEFINITIONS: For the purpose of this rule, the following definitions shall
apply, in addition to those definitions found in Rule 100 (General Provisions and Definitions) of these
rules. In the event of any inconsistency between any of the Maricopa County Air Pollution Control
Rules, the definitions in this rule take precedence.
201 AFTERCOOLER/INTERCOOLER: A system that cools the engine intake air or air/fuel
mixture after the air exits the turbocharger and prior to the introduction into the cylinder,
thereby lowering NOX emissions.
202 ALTERNATIVE FUELS: Substitutes for oil-derived and fossil-fuel derived fuels,
including but not limited to biodiesel, propane, ethanol or methanol.
202 203 COGENERATION UNIT: A stationary RICE unit that burns fuel to simultaneously
produce electricity and heat in a single thermodynamic process and is usually located in close
proximity to the equipment requiring the heat energy.
204 COMMISSIONING PERIOD: The final phase of the stationary RICE construction process
during which all mechanical, electrical, and control systems for the RICE and all related
equipment are checked, and all performance measures specified in the purchase agreement are
confirmed. For the purposes of this rule, a stationary RICE may not be used for its intended
purpose or any other beneficial use during the commissioning period. If a non-emergency
engine subject to this rule is also subject to a condition in a Maricopa County Air Quality Permit
limiting total hours of operation, the hours of operation during the commissioning period shall
be included when determining compliance with the permitted limit on total hours of operation.
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203 205 COMPRESSION-IGNITION ENGINE: A stationary RICE with operating characteristics
wherein the principal mechanism of igniting the fuel and air mixture in the cylinders is the
compression of air in the cylinder until it is so hot that any fuel injected into the air or mixed
with the air ignites. In this type of engine, a separate ignition source, such as a spark plug, is not
used.
204 DIESEL ENGINE: A type of compression-ignition engine.
205 206 EMERGENCY ENGINE: A stationary RICE whose sole function is to provide back-up
power when electric power from the local utility is interrupted or when operated solely for any
of the reasons listed in Section 104 of this rule. An emergency engine, for the purposes of this
rule, shall not be used to supply standby power due to a voluntary reduction in power by a
utility or power company, supply power for distribution or sale to the grid, or supply power at
a source in order to avoid peak demand charges or high electric energy prices during on-peak
price periods and shall not exceed 500 hours of operation per calendar year including the 100
hours listed in Section 104.5 of this rule. A stationary RICE that meets all of the following
criteria:
206.1 Is operated solely for any of the reasons listed in Section 104 of this rule;
206.2 Does not exceed 500 hours of operation per any twelve consecutive months, including
the 100 hours per calendar year listed in Section 104.5 of this rule and including any
hours of operation that occur during the commissioning period; and
206.3 Is not operated to supply standby power due to a voluntary reduction in power by a
utility or power company, or to supply power for distribution or sale to the grid, or to
supply power at a source in order to avoid peak demand charges or high electric
energy prices during on-peak price periods.
206 ENGINE FAMILY: A group of stationary RICE with similar design features such as fuel type,
cooling medium, method of air aspiration, combustion chamber design including cylinder bore
and stroke, exhaust after treatment (if any), method of fuel admission, and method of control.
These engines are also expected to have similar emission and operating characteristics
throughout their useful lives.
207 EQUIVALENT REPLACEMENT ENGINE: A stationary RICE that is substituted for
another stationary RICE that is intended to perform the same or similar function as the original
stationary RICE and where all of the following conditions exist:
207.1 The equivalent replacement engine results in equal or lower air contaminant emissions
than the original stationary RICE; and
207.2 The equivalent replacement engine meets the emission control technology standards
contained in Section 304 of this rule; and
207.3 The rated bhp of the equivalent replacement engine does not exceed the rated bhp of
the original stationary RICE (or sum of original stationary RICE) by more than 20
percent, for the purpose of this rule. For every percentage point increase of the rated
bhp, there shall be an associated decrease in emissions of nitrogen oxides, expressed as
a mass per unit time, equal to or exceeding two percentage points.
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207 GASOLINE: Any fuel sold in any State for use in motor vehicles and motor vehicle
engines, or nonroad or stationary engines, and commonly or commercially known or sold as
gasoline.
208 IDENTICAL REPLACEMENT ENGINE: A stationary RICE that is substituted for
another stationary RICE that is intended to perform the same or similar function as the original
stationary RICE and where all of the following conditions exist:
208.1 The identical replacement engine results in equal or lower air contaminant emissions
than the original stationary RICE; and
208.2 The identical replacement engine meets the emission control technology standards
contained in Section 304 of this rule; and
208.3 The identical replacement engine has the same manufacturer type, model number, and
manufacturer’s rated bhp as the original stationary RICE.
209 LEAN-BURN ENGINE: A spark-ignition engine with an air-to-fuel operating range that
has more air present than is needed to burn the fuel present and cannot be adjusted to
operate with an exhaust oxygen concentration of less than or equal to 2%.
210 LIQUEFIED PETROLEUM GAS (LPG): Any liquefied hydrocarbon gas obtained as a
by-product in petroleum refining or natural gas production.
210 211 LOCATION: Any single site at a building, structure, facility or installation.
212 LOW SULFUR OIL: Fuel oil containing less than or equal to 0.05% sulfur by weight.
213 NATURAL GAS: A naturally occurring mixture of hydrocarbon and non-hydrocarbon
gases found in geologic formations beneath the Earth’s surface, of which the principal
constituent is methane.
211 214 NON-EMERGENCY ENGINE: A stationary RICE that is dedicated to a process or
processes for the purpose of supplying primary mechanical or electrical power not an
emergency engine.
212 NONROAD INTERNAL COMBUSTION (IC) ENGINE:
212.1 Equipment that meets the following requirements are nonroad IC engines:
a. An internal combustion engine that is (or will be) used in or on a piece of
equipment that is self-propelled or serves a dual purpose by both propelling itself
and performing another function (such as garden tractors, off-highway mobile
cranes, and bulldozers); or
b. An internal combustion engine that is (or will be) used in or on a piece of
equipment that is intended to be propelled while performing its function (such as
lawnmowers and string trimmers); or
c. An internal combustion engine that by itself or in or on a piece of equipment is
portable or transportable, meaning designed to be and capable of being carried
87

or moved from one location to another. Indicia of transportability include but
are not limited to, wheels, skids, carrying handles, dollies, trailers, or platforms.
212.2 The following are not nonroad IC engines:
a. An engine used to propel a motor vehicle, an aircraft, or equipment used solely
for competition; or
b. An engine regulated by a federal New Source Performance Standard
promulgated under Section 111 of the Clean Air Act; or
c. An engine otherwise included in Section 212.1(c) of this rule that remains or will
remain at a location for more than 12 consecutive months or a shorter period of
time for an engine located at a seasonal source. A location is any single site at a
building, structure, facility, or installation. Any engine (or engines) that replace(s)
an engine at a location and that is intended to perform the same or similar
function as the engine replaced will be included in calculating the consecutive
time period. An engine located at a seasonal source is an engine that remains at a
seasonal source during the full annual operating period of the seasonal source. A
seasonal source is a stationary source that remains in a single location on a
permanent basis (i.e. at least two years) and that operates at that single location
approximately three months (or more) each year. This paragraph does not apply
to an engine after the engine is removed from the location.
213 215 PARTS(S) PER MILLION, DRY BY VOLUME DRY (PPMDVD): A unit of
proportion used to express concentration that is corrected to a dry basis. A unit of
proportion equal to 10-6 that is measured on a dry basis (minus water) at 15% oxygen.
214 216 RATED BRAKE HORSEPOWER (RATED BHP): The maximum brake horsepower
(bhp) specified by the engine manufacturer for the engine application, usually listed on the
nameplate of the engine. If the engine has been altered so that the maximum brake
horsepower is different than the rated brake horsepower on the nameplate, then the maximum
brake horsepower shall be considered the rated brake horsepower.
217 RECONSTRUCTED: Repairs, changes, or improvements to a stationary RICE where the
fixed capital cost of the new and refurbished engine components exceeds 75% of the fixed
capital cost of purchasing an entirely new engine with the same brake horsepower rating; or
construction of an engine on a previously used engine block if the engine is constructed using
all new components except for the engine block. For the purposes of this rule, the cost of
installing emission controls (such as a diesel particulate filter, a three-way catalyst, or a selective
catalytic reduction system) is not included when determining whether or not an engine has
been reconstructed.
215 218 RICH-BURN ENGINE: A spark-ignition engine that is not a lean-burn engine.
216 219 SPARK-IGNITION ENGINE: A stationary RICE wherein the fuel is usually mixed with
intake air before introduction into the combustion chamber resulting in a relatively
homogeneous air/fuel mixture in the combustion chamber, at which time a spark plug, or
other device, then ignites the air/fuel mixture.
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217 220 STATIONARY RECIPROCATING INTERNAL COMBUSTION ENGINE
(RICE): A reciprocating, piston-driven internal combustion engine that is operated or
intended to be operated at one specific location for more than 12 consecutive months or
that is attached to a foundation at the location. An engine that replaces an engine at a
location and is intended to perform the same or similar function as the engine being replaced
will be included in calculating the consecutive time period. A stationary RICE is not a
nonroad engine.
218 221 SULFUR OXIDES (SOX): Oxides of sulfur calculated as equivalent sulfur dioxide.
219 222 ULTRA LOW SULFUR OIL DIESEL: Fuel oil containing less than or equal to 0.0015%
sulfur by weight.
220 223 WASTE DERIVED FUEL GAS: A gaseous fuel that is generated from the biodegradation
of solid or liquid waste including, but not limited to, digester gas and landfill gas.
SECTION 300 – STANDARDS:
301 LIMITATIONS FOR STATIONARY RICE – FUEL REQUIREMENTS: An owner or
operator of an engine a stationary RICE that meets the criteria listed in Section 102 of this
rule shall comply with either one of the following:
301.1 Use any fuel that contains no more than 0.0015% sulfur by weight, alone or in
combination with other fuels. Use ultra low sulfur oil, except as provided in Sections
301.1a or 301.1b of this rule.
a. Engines that are not subject to the 40 CFR 60 Subpart IIII or 40 CFR 63
Subpart ZZZZ may use existing low sulfur oil purchased (or otherwise obtained)
prior to November 2, 2016 until depleted.
b. Engines that are subject to 40 CFR 60 Subpart IIII or 40 CFR 63 Subpart ZZZZ
must also comply with the fuel requirements in the applicable subpart.
301.2 Use any waste derived fuel gas that contains no more than 0.08% sulfur by weight,
alone or in combination with other fuels.
301.3 Use gasoline that meets the sulfur standard of 80 ppm as a per-gallon cap.
301.4 Use natural gas, liquefied petroleum gas (LPG), or any alternative fuel that contains no
more than 0.05% sulfur by weight, alone or in combination with other fuels.
302 GOOD COMBUSTION PRACTICES/TUNING PROCEDURE MAINTENANCE
REQUIREMENTS FOR STATIONARY RICE: An owner or operator of an engine a
stationary RICE that meets the criteria listed in Section 102 of this rule shall conduct
preventative maintenance or tuning procedures as recommended by the engine manufacturer
maintain the stationary RICE in accordance with the manufacturer's written instructions or
in accordance with the maintenance schedule provided by the manufacturer’s authorized
service provider to ensure good combustion practices to minimize NOX emissions. A
handheld monitor may be used if so desired by the owner or operator for measurement of
NOX and CO concentrations in the effluent stream after each adjustment is made; this may
assist in determining that the proper adjustment has been made to minimize NOX and CO
emissions. A handheld monitor may be used by the Control Officer to determine
89

compliance with this section. Alternatively, the owner or operator shall conduct preventative
maintenance according to the following schedule, including include all of the following in
the tuning procedures, if the engine is so equipped, and if such procedures are appropriate to
the type of engine:.
302.1 Lubricating Oil and Filter: Change once every three months or after no more than
300 hours of operation, whichever occurs last.
302.2 Inlet Air Filter: Clean once every three months or after no more than 300 hours of
operation and replace every 1,000 hours of operation or every year, whichever occurs
last.
302.3 Fuel Filter: Clean once every year or replace (if cartridge type) once every 1,000
hours of operation, whichever occurs last.
302.4 Check and adjust the following once every year or after no more than 1,000 hours of
operation, whichever occurs last:
a. Intake and exhaust valves
b. Spark plugs (if so equipped)
c. Spark timing and dwell or fuel injection timing (if adjustable), and
d. Carburetor mixture (if adjustable).
302.5 Spark Plugs and Ignition Points: Replace after 3,000 hours of operation or every year
whichever occurs last
302.6 Coolant: Change after 3,000 hours of operation or every year whichever occurs last.
302.7 Exhaust System: Check for leaks and/or restrictions after 3,000 hours of operation
or every year whichever occurs last.
302.1 The following maintenance procedures shall be completed no less frequently than
every 300 hours of operation (for engines that operate 300 hours per year or more)
or at least once every 12 months (for engines that operate less than 300 hours per
year):
a. Clean the inlet air filter (if so equipped);
b. Change oil filter; and
c. Change the lubricating oil or conduct an oil analysis to determine Total Base
Number, viscosity, and percent water content. The lubricating oil must be
replaced within 2 business days after the analytical results are received if any of
the following condemning limits are exceeded:
(i) Total Base Number is less than 30% of the Total Base Number of the oil
when new;
(ii) Viscosity of the oil has changed by more than 20 percent from the viscosity
of the oil when new; or
(iii) Percent water content (by volume) is greater than 0.5.
302.2 The following maintenance procedures shall be completed no less frequently than
every 1,000 hours of operation (for engines that operate 1,000 hours per year or
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more) or at least once every 12 months (for engines that operate less than 1,000
hours per year):
a. Replace the inlet air filter;
b. Clean all fuel filters (except cartridge type fuel filters);
c. Replace cartridge type fuel filters;
d. Check and adjust the intake and exhaust valves;
e. Check and adjust the spark plugs (if so equipped);
f. Check and adjust the spark timing and dwell or fuel injection timing (if
adjustable); and
g. Check and adjust the carburetor mixture (if adjustable).
302.3 The following maintenance procedures shall be completed no less frequently than
every 3,000 hours of operation (for engines that operate 3,000 hours per year or
more) or at least once every 12 months (for engines that operate less than 3,000
hours per year):
a. Replace spark plugs and ignition points (if so equipped);
b. Change coolant (if so equipped); and
c. Check the exhaust system and repair all leaks and/or restrictions.
303 LIMITATIONS FOR STATIONARY RICE – OPACITY: An owner or operator of an
engine a stationary RICE that meets the criteria in Section 102 of this rule shall not discharge
into the ambient air from any such engine any air contaminant, other than uncombined
water, in excess of 20% opacity.
304 LIMITATIONS FOR NON-EMERGENCY ENGINES 250 RATED BHP OR
GREATER: In addition to meeting the standards in Sections 301, 302 and 303 of this rule,
an owner or operator of a non-emergency engine that meets the criteria in Section 102 of
this rule shall comply with Sections 304.1 or 304.2 of this rule.
304.1 Engine Requirements for Non-Emergency Engines Compression-Ignition
Engines That Are Not Located At A Major Source of NOX: The emissions in
parts per million by dry volume (ppmdv) or grams per bhp (g/bhp) from the non-
emergency engines shall comply with either Table 1 or Table 2 of this rule. An owner
or operator of a non-emergency compression-ignition engine that is rated above 250
bhp and is not located at a major source of NOX shall comply with the engine
requirements in Table 324-1, as applicable, depending on the date the engine was
manufactured or reconstructed (whichever occurred later) and the rated brake
horsepower of the engine:
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TABLE 324-1
COMPRESSION-IGNITION ENGINES
MANUFACTURED OR
MODIFIED
RECONSTRUCTED RATED BHP ENGINE REQUIREMENTS*
770 ppmvdv or 10 g/bhp-hr. NOX or
turbocharger with
aftercooler/intercooler or
Prior to October 22, 2003 250-399 4-degree injection timing retard delay
550 ppmvdv or 7.2 g/bhp-hr. NOX or
turbocharger with
400 plus aftercooler/intercooler or
Prior to October 22, 2003 More than 399 4-degree injection timing retard delay
530 ppmvdv or 6.9 g/bhp-hr. NOX; or
turbocharger with
aftercooler/intercooler or
4-degree injection timing retard;
On or after October 22, 2003 but >250 1,000 ppmvdv CO;
prior to July 11, 2005 More than 250 0.40 g/bhp-hr PM
* ppmvd emission standards are corrected to 15% oxygen.
304.2 Requirements for Non-Emergency Spark-Ignition Engines That Are Not
Located At A Major Source of NOX: An owner or operator of a non-emergency
spark-ignition engine that is rated above 250 bhp and is not located at a major source
of NOX shall comply with the engine requirements in Table 324-2, as applicable,
depending on the date the engine was manufactured or reconstructed (whichever
occurred later) and whether it is a lean-burn or rich-burn engine:
TABLE 324-2
SPARK-IGNITION ENGINES
LEAN-BURN ENGINES
VOLATILE
MANUFACTURED OXIDES OF ORGANIC CARBON
OR MODIFIED RATED NITROGEN COMPOUND MONOXIDE
RECONSTRUCTED BHP (NOX**) (VOC**) (CO**)
280 ppmvdv
or 4.0 g/bhp-
hr 800 ppmvdv or 5.0 4,500 ppmvdv
Prior to October 22, or three-way g/bhp-hr or three-way
2003 >250 catalyst* or three-way catalyst* catalyst*
On or after October 22, 110 ppmvdv 800 ppmdv or 5.0
2003 but prior to June or 1.5 g/bhp- g/bhp-hr
12, 2006 >250 hr Not Applicable 4,500 ppmvdv
RICH-BURN ENGINES
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VOLATILE
MANUFACTURED OXIDES OF ORGANIC CARBON
OR MODIFIED RATED NITROGEN COMPOUND MONOXIDE
RECONSTRUCTED BHP (NOX**) (VOC**) (CO**)
280 ppmvdv
or 4.0 g/bhp- 800 ppmvdv or 5.0 4,500 ppmvdv
Prior to October 22, hr or three- g/bhp-hr or three-way or three-way
2003 >250 way catalyst* catalyst* catalyst*
20 ppmvdv or 800 ppmdv or 5.0
On or after October 22, 0.30 g/bhp-hr g/bhp-hr or three-way 4,500 ppmvdv
2003 but prior to June or three-way catalyst* or three-way
12, 2006 >250 catalyst* Not Applicable catalyst*
* The three-way catalyst shall provide a minimum of 80% control efficiency for NOX and CO for those engines
fueled with natural gas, propane or gasoline. In addition, the three-way catalyst shall also provide a minimum of at
least 50% control efficiency for VOC for those engines fueled by gasoline.
** ppmvd emission standards are corrected to 15% oxygen.
304.3 Emission Limits for Non-Emergency Engines That Are Located At A Major
Source of NOX: An owner or operator of a non-emergency engine that is rated
above 50 bhp and is located at a major source of NOX shall comply with the engine
requirements in Table 324-3, as applicable, depending on the engine type:
TABLE 324-3
ENGINE TYPE NOX* VOC* CO* PM
110 ppmvd or 800 ppmvd or Not
Spark-Ignition Lean-Burn 1.5 g/bhp-hr 5.0 g/bhp-hr 4,500 ppmvd Applicable
20 ppmvd or 800 ppmvd or Not
Spark-Ignition Rich-Burn 0.30 g/bhp-hr 5.0 g/bhp-hr 4,500 ppmvd Applicable
530 ppmvd or Not
Compression-Ignition 6.9 g/bhp-hr Applicable 1,000 ppmvd 0.40 g/bhp-hr
* ppmvd emission standards are corrected to 15% oxygen.
304.2 Federal Standards of Performance for Non-Emergency Engines: An owner or
operator of an engine listed in Sections 304.2(a) or (b) of this rule shall comply with
the federal standards of performance for compression-ignition engines set forth in
40 CFR Part 60, Subpart IIII or spark-ignition engines set forth in 40 CFR Part 60,
Subpart JJJJ and in all accompanying appendices as incorporated by reference in Rule
360 (New Source Performance Standards) of these rules. Whenever more than one
provision in this rule applies to such engine or whenever a provision in this rule and
a pr7ovision in the federal standards apply to such engine, the provision or
combination of provisions resulting in the lowest rate of emissions shall apply, unless
otherwise specifically exempted or designated.
a. 40 CFR Part 60, Subpart IIII applies to all of the following non-emergency
compression-ignition engines:
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(1) Any stationary compression-ignition IC engine that was ordered after July 11,
2005 and manufactured after April 1, 2006.
(2) Any stationary compression-ignition IC engine that was modified or
reconstructed after July 11, 2005.
b. 40 CFR Part 60, Subpart JJJJ applies to the following non-emergency spark-
ignition engine:
(1) Any stationary spark-ignition engine that was ordered after June 12, 2006 and
manufactured on or after:
(a) July 1, 2007 for engines with a rated bhp greater than or equal to 500
(except lean burn engines with a rated bhp greater than or equal to 500
and less than 1,350)
(b) January 1, 2008 for lean burn engines with a rated bhp greater than or
equal to 500 and less than 1,350
(c) July 1, 2008 for engines with a rated bhp less than 500.
(2) Any stationary spark-ignition engine that was modified or reconstructed after
June 12, 2006.
305 EFFICIENCY ALLOWANCE: Each emission limit expressed in Tables 324-1 or 324-2 of
this rule may be multiplied by X, where X equals the engine efficiency (E) divided by a
reference efficiency of 30 percent. Engine efficiency shall be determined by one of the
following methods whichever is higher:
a. E = (Engine Output) X (100) ÷ (Energy Input) where Energy Input is determined by a
fuel measuring device accurate to +/- 5 % and is based upon the higher heating value
(HHV) of the fuel. Percent efficiency (E) shall be averaged over 15 consecutive minutes
and measured at peak load for the applicable engine.
b. E = (Manufacturers Rated Efficiency [Continuous] at (LHV) X (LHV) ÷ (HHV) where
LHV = the lower heating value of the fuel Engine efficiency (E) shall not be less than 30
percent; an engine with an efficiency lower than 30 percent shall be assigned an
efficiency of 30 percent for the purposes of this rule.
306 305 EQUIVALENT REPLACEMENT ENGINE OR IDENTICAL REPLACEMENT
ENGINE: An equivalent replacement engine or an identical replacement engine shall be
treated as the original stationary RICE that it replaces for the purposes of compliance with this
rule.
307 MODIFICATION TO A STATIONARY RICE: If a modification, including the contractual
obligation to undertake and complete an order for an engine, is made to a stationary RICE,
then such engine shall comply with all applicable provisions of this rule. The date of the
modification shall be the trigger for when the modification is subject to the provisions of
Section 304 of this rule. Whenever a provision in this rule and a provision in Section 304 of
this rule apply to such engine, the provision or combination of provisions resulting in the
lowest rate of emissions shall apply, unless otherwise specifically exempted or designated.
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308 306 NON-RESETTING TOTALIZING HOUR METER: The owner or operator of a
stationary RICE, subject to any provision of this rule, except for those engines being
removed from service under Section 401 of this rule, shall install, and operate, and maintain
a non-resetting totalizing hour meter. If the non-resetting totalizing hour meter is found to
be malfunctioning, operation of the engine shall cease until corrective action(s) can be
implemented or the function of the meter is restored the owner or operator shall:
306.1 Record hours of operation daily until the function of the hour meter is restored; and
306.2 Restore the function of the hour meter within two weeks. Or, if it is not possible to
restore the function of the hour meter within two weeks, the owner or operator shall
notify the Control Officer in writing and provide a schedule for restoration of the
function of the hour meter.
SECTION 400 – ADMINISTRATIVE REQUIREMENTS
401 COMPLIANCE SCHEDULE-STATIONARY RICE BEING REMOVED FROM
SERVICE: If a stationary RICE must be removed from service because such engine does
not comply with the emission limits listed in Section 300 of this rule, then the stationary
RICE shall be removed from service no later than November 2, 2017 [insert date one year
after rule adoption]. The stationary RICE that replaces such engine shall comply with all
applicable provisions of this rule and shall comply with Section 304 of this rule upon
installation.
402 COMPLIANCE SCHEDULE-NON-RESETTING TOTALIZING HOUR
METER: The owner or operator of a stationary RICE that is not equipped with a non-
resetting totalizing hour meter on [insert date of rule adoption], subject to any provision of
this rule, except for those engines and is not being removed from service under Section 401
of this rule, shall install, and operate, and maintain a non-resetting totalizing hour meter on
each such engine no later than November 2, 2017 [insert date one year after rule adoption].
403 COMPLIANCE SCHEDULE-ENGINES AT A SOURCE THAT BECOMES A
MAJOR SOURCE: If a non-emergency engine is located at a source that becomes a major
source of nitrogen oxides after [insert date of rule adoption], the owner or operator shall
demonstrate compliance with the emission limits in Table 324-3 within one year after the
source becomes a major source of nitrogen oxides.
SECTION 500 – MONITORING AND RECORDS
501 COMPLIANCE DETERMINATION:
501.1 Stationary RICE Non-Emergency Engines That Are Not Located At A Major
Source of NOX: An owner or operator of a stationary RICE non-emergency engine
which is subject to the requirements in Section 304.1 or 304.2 of this rule shall
demonstrate compliance with all of the using one of the following methods, as
applicable:
a. With Section 300 of this rule, by recordkeeping according to Section 502 of this
rule. Emission testing using the applicable test methods listed in Section 503 of
this rule shall be performed upon the request of the Control Officer. Provide
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documentation that the stationary RICE is certified by the manufacturer to
comply with emission limits in 40 CFR 60 Subpart IIII or 40 CFR 60 Subpart
JJJJ that are more stringent than the applicable emission limits in Table 324-1 or
324-2 of this rule, and provide documentation that the engine is installed,
operated, and maintained in accordance with the manufacturer's specifications.
b. With Section 304.2 of this rule, by one of the following: Conduct a performance
test in accordance with Section 501.4 of this rule at least once every 5 years. The
performance test shall demonstrate compliance with one of the following
requirements:
(1) A statement from the manufacturer that the engine meets the most stringent
emissions standards found in this rule or 40 CFR Parts 89, 90, and 1039
applicable to the engine and its model year at the time of manufacture. The
applicable emission limits in units of grams per brake horsepower-hour
(g/bhp-hr); or
(2) Emission testing using the applicable test methods listed in Section 503 of
this rule shall be performed upon the request of the Control Officer. The
applicable emission limits in units of ppmvd; or
(3) The three-way catalyst provides a minimum of 80% control efficiency for
NOX and CO for engines fueled with natural gas, propane or gasoline, and
the three-way catalyst also provides a minimum of 50% control efficiency for
VOC for engines fueled by gasoline.
c. With 40 CFR Part 60.4213, for a stationary RICE with a displacement of greater
than or equal to 30 liters per cylinder. Provide documentation that the non-
emergency compression-ignition engine was manufactured or reconstructed
(whichever occurred later) prior to October 22, 2003 and provide documentation
that the non-emergency compression-ignition engine is equipped with a
turbocharger with an aftercooler/intercooler.
d. Provide documentation that the non-emergency compression-ignition engine
was manufactured or reconstructed (whichever occurred later) prior to October
22, 2003 and:
(1) Provide documentation that the injection timing has been set at 4 degrees
below the factory setting for the engine. Written verification of the factory
set timing, along with documentation that the engine timing has been delayed
by 4 degrees must be submitted; or
(2) Provide documentation that the injection timing has been set at 4 degrees
below the manufacturer's standard timing of the engine. Written verification
of the manufacturer's standard timing of the engine prior to tuning for NOX
control, along with documentation that the timing has been delayed by 4
degrees must be submitted; or
(3) Provide documentation that the injection timing has been set at 16 degrees
below top dead center or less (if information regarding the manufacturer's
standard timing or factory set timing is not available).
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501.2 Non-Emergency Engines That Are Located At A Major Source of Nitrogen
Oxides: An owner or operator of a non-emergency engine which is subject to
emission limits in Section 304.3 of this rule shall demonstrate compliance by
conducting a performance test in accordance with Section 501.4 of this rule at least
once every 2 years. The performance test shall demonstrate compliance with the
applicable emission limits in units of grams per brake horsepower-hour (g/bhp-hr)
or ppmvd.
A statement from the manufacturer that the engine meets the most stringent
emissions standards found in this rule or 40 CFR Parts 89, 90, and 1039 applicable to
the engine and its model year at the time of manufacture.
(2)Emission testing using the applicable test methods listed in Section 503 of this
rule shall be performed upon the request of the Control With 40 CFR Part 60.4213,
for an engine family with a displacement of greater than or equal to 30 liters per
cylinder.
501.3 Representative Performance Testing: An owner or operator may demonstrate
compliance with the applicable emission limits or control efficiency requirements in
Table 324-1, Table 324-2, or Table 324-3 of this rule by conducting representative
performance testing in accordance with Section 501.4 of this rule, provided all of the
following requirements are satisfied:
a. The engines are located at the same stationary source;
b. The engines were produced by the same manufacturer, have the same model
number or other manufacturer's designation in common, and have the same
rated capacity and operating specifications;
c. The engines are operated and maintained in a similar manner;
d. At least one engine or one third of the engines in the specified group, whichever
is greater, are tested each time a performance test is required;
e. Each time a performance test is required, different engines are tested so that all
engines in the specified group are tested before any engines in the representative
group are retested; and
f. If emissions from any engine in the specified group exceed an applicable
emission limit, or if the control efficiency for any pollutant controlled by a three-
way catalyst is lower than the required control efficiency, the owner or operator
shall demonstrate that each engine in the specified group is in compliance with
the applicable limits by conducting a performance test on each engine in the
specified group.
501.4 Performance Test Conditions: Performance tests shall be conducted using the test
methods listed in Section 503 of this rule. Testing for stationary RICE shall be
completed at either the maximum operating load or no less than 80% of the rated bhp.
If the owner or operator of an engine demonstrates to the Control Officer that the
engine cannot operate at these conditions, then emissions source testing shall be
performed at the highest achievable continuous rated bhp or under the typical duty
cycle or typical operational mode of the engine. The result of the performance test
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shall be the arithmetic mean of the results of three test runs. Each test run shall have a
minimum sample time of one hour.
501.3 501.5 Ultra Low Sulfur Diesel Fuel-Sulfur Verification: If the Control Officer requests
documentation of the sulfur content of the fuel to demonstrate the 0.0015% limit,
the The owner or operator of an engine fueled with gasoline shall submit
documentation that gasoline was purchased within the United States. The owner or
operator of an engine fueled with diesel, natural gas, LPG, or an alternative fuel shall
submit one of the following documents listing the accurate sulfur content of the fuel
based on enforceable test methods as approved by the Administrator to determine
the sulfur content:
a. Fuel receipts, or
b. Contract specifications, or
c. Pipeline meter tickets, or
d. Fuel supplier information, or
e. Purchase records, or
f. Test results of the fuel for sulfur content.
The items listed above must provide accurate sulfur content values or be based on
enforceable test methods as approved by the Administrator to determine the sulfur
content.
501.4 501.6 Waste Derived Fuel Gas - Sulfur Verification: The owner or operator shall
submit documentation of the concentration of the sulfur level content of the waste
derived fuel gas to the Control Officer upon request. The sulfur content of gaseous
fuels shall be determined by South Coast Air Quality Management District Method
307-91 Determination of Sulfur in a Gaseous Matrix.
501.5 Test Method Conditions: The owner or operator shall use the test methods listed in
Section 503 of this rule to determine compliance with the limitations listed in Tables
1 or 2 of this rule. Testing for stationary RICE shall be completed under steady state
conditions at either the maximum operating load or no less than 80% of the rated bhp.
If the owner or operator of an engine demonstrates to the Control Officer that the
engine cannot operate at these conditions, then emissions source testing shall be
performed at the highest achievable continuous rated bhp or under the typical duty
cycle or typical operational mode of the engine.
502 RECORDKEEPING/RECORDS RETENTION: The owner or operator of a stationary
RICE subject to this rule shall comply with the following requirements and retain records for
at least 5 years:
502.1 Records Required for a Stationary RICE List: An owner or operator of a stationary
RICE, including emergency engines, non-emergency engines, and low usage non-
emergency engines, shall keep a record that includes an initial one time entry that lists
Maintain a list of stationary RICE that includes all of the following information for
each stationary RICE: the particular engine combustion type (compression-ignition, or
lean-burn spark-ignition, or rich burn, lean burn rich-burn spark-ignition);
manufacturer; model designation, rated bhp, serial number, and where the the location
of each engine is located on the site at the facility. If the equipment list associated with
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the current permit includes all of the required information for each stationary RICE
located at the facility, this requirement may be fulfilled by keeping a complete copy of
the current permit, including the equipment list, in a readily accessible location at the
facility where the engines are located, and by providing the equipment list to the
Control Officer upon request.
502.2 Monthly Records Required for Non-Emergency Engines Operation Records: An
owner or operator of a non-emergency engine stationary RICE shall maintain a
monthly record for non-emergency engines which shall include records of the monthly
and 12-month rolling total hours of operation for each stationary RICE. For
emergency engines, the operation records shall also include:
a. Hours of operation; and Monthly and annual hours of operation for reliability
related activities such as engine readiness, calibration, or maintenance, or to
prevent the occurrence of an unsafe condition during electrical system
maintenance; and
b. Type of fuel used, and The number of operating hours for emergency use and an
explanation for the emergency use.
c. Documentation verifying compliance with sulfur fuel content.
502.3 Annual Records Required for Non-Emergency Engines Maintenance Records: An
owner or operator of a non-emergency engine stationary RICE shall maintain an
annual record of the practices/procedures that are followed in order to comply with
Section 302 (Good Combustion Practices/Tuning Procedures for Stationary RICE) of
this rule records of all stationary RICE maintenance (including the date when
maintenance was performed and the maintenance procedures that were performed). If
an owner or operator of a non-emergency engine demonstrates compliance with the
requirements in Section 304.1 of this rule using the method specified in Section
501.1(d) of this rule, the maintenance record shall include documentation of the
injection timing setting each time maintenance is performed on the stationary RICE.
In addition, one of the following documents shall be available at all times at the facility
where the stationary RICE is located:
a. The manufacturer’s written instructions for operation and maintenance of each
stationary RICE;
b. A written maintenance schedule provided by the manufacturer’s authorized service
provider; or
c. A written maintenance plan indicating which of the tuning procedures listed in
Section 302 of this rule are applicable to each stationary RICE.
502.4 Fuel Records: Required for an Emergency Engine or a Low Usage Non-Emergency
Engine An owner or operator of an emergency engine or a low usage non-emergency
engine that meets the exemptions listed in Sections 104 and 105 of this rule shall keep
an engine record that includes:
a. Monthly rolling twelve month total of hours of operation, including hours of
operation for testing, reliability and maintenance; and Maintain records of the type
and amount of fuel purchased for use in the stationary RICE (e.g. receipts, pipeline
tickets, or bills of lading); and
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b. Fuel type and sulfur content of fuel; and Maintain records of the sulfur content of
any fuel that is used in the stationary RICE, excluding gasoline. For gasoline,
maintain records that the fuel was purchased in the United States.
c. Explanation for the use of the engine if it is used as an emergency engine.
502.5 Manufacturer's Operation and Maintenance Instructions: An owner or operator
of an engine that is subject to the requirements of Section 302 of this rule shall keep
the manufacturer's written instructions for operation and maintenance of the engine
available at the facility where the engine is located at all times. If the manufacturer's
written instructions are not available, the owner or operator shall keep a preventative
maintenance plan, indicating which procedures in Section 302 of this rule are
appropriate to the engine, available at the facility where the engine is located at all
times.
502.6 Nonroad Engine Records: An owner or operator of a nonroad engine shall maintain
the following records for each non-road engine:
a. Date that each engine is brought to the stationary source; and
b. For engines located at a stationary source greater than 14 consecutive days:
(1) Make, model, serial number, and rated capacity (bhp hours) of the engine; and
(2) Date of each instance in which the engine is moved from its existing location,
and the reason why the engine was moved; and
(3) Fuel type and sulfur content of the fuel.
503 COMPLIANCE DETERMINATION-TEST METHODS INCORPORATED BY
REFERENCE: The following test methods are approved for use for the purpose of
determining compliance with this rule. The test methods are incorporated by reference in Rule
360 and Appendix G of the Maricopa County Air Pollution Control Regulations. Alternative
test methods as approved by the Administrator or other EPA-approved test methods may be
used upon written approval from the Control Officer. When more than one test method is
permitted for the same determination, an exceedance under any method will constitute a
violation. Copies of test methods referenced in this section are available at the Maricopa
County Air Quality Department.
503.1 EPA Reference Methods 1 (“Sample and Velocity Traverses for Stationary Sources”)
and 1A (“Sample and Velocity Traverses for Stationary Sources with Small Stacks or
Ducts”) (40 CFR 60, Appendix A).
503.2 EPA Reference Methods 2 (“Determination of Stack Gas Velocity and Volumetric
Flow Rate”), 2A (“Direct Measurement of Gas Volume Through Pipes and Small
Ducts”), 2C (“Determination of Stack Gas Velocity and Volumetric Flow Rate in
Small Stacks or Ducts”), and 2D (“Measurement of Gas Volumetric Flow Rates in
Small Pipes and Ducts”) (40 CFR 60, Appendix A).
503.3 EPA Reference Methods 3 (“Gas Analysis for the Determination of Dry Molecular
Weight”), 3A (“Determination of Oxygen and Carbon Dioxide Concentrations in
Emissions from Stationary Sources (Instrumental Analyzer Procedure"), 3B (“Gas
Analysis for the Determination of Emission Rate Correction Factor of or Excess
100

Air”), and 3C (“Determination of Carbon Dioxide, Methane, Nitrogen and Oxygen
from Stationary Sources”) (40 CFR 60, Appendix A).
503.4 EPA Reference Method 4 (“Determination of Moisture Content in Stack Gases”)
(40 CFR 60, Appendix A).
503.5 EPA Reference Method 5 (“Determination of Particulate Emissions from Stationary
Sources”) (40 CFR 60, Appendix A)
503.6 EPA Reference Method 202 (“Determination of Dry Impinger Method for
Determining Condensable Particulate Emissions from Stationary Sources”) (40 CFR
51, Appendix M).
503.7 EPA Reference Methods 7 (“Determination of Nitrogen Oxide Emissions from
Stationary Sources”), 7A (“Determination of Nitrogen Oxide Emissions fromform
Stationary Sources - Ion Chromatographic Method”), 7B (“Determination of
Nitrogen Oxide Emissions from Stationary Sources – Ultraviolet Spectrometry
Spectrophotometry Method”), 7C (“Determination of Nitrogen Oxide Emissions
from Stationary Sources – Alkaline Permanganate/Colorimetric Method”), 7D
(“Determination of Nitrogen Oxide Emissions from Stationary Sources – Alkaline –
-Permanganate/Ion Chromatographic Method”), and 7E (“Determination of
Nitrogen Oxide Emissions from Stationary Sources – Instrumental Analyzer
Method“ Procedure”), (40 CFR 60, Appendix A).
503.8 EPA Reference Method 9 (“Visual Determination of the Opacity of Emissions from
Stationary Sources”) (40 CFR 60, Appendix A).
503.9 EPA Reference Method 10 (“Determination of Carbon Monoxide from Stationary
Sources”) (40 CFR 60, Appendix A).
503.10 EPA Reference Method 18 (“Measurement of Gaseous Organic Compound
Emissions by Gas Chromatography”) (40 CFR 60, Appendix A).
503.11 EPA Reference Method 25A (“Determination of Total Gaseous Organic
Concentration Using a Flame Ionization Analyzer”) (40 CFR 60, Appendix A).
503.12 ASTM D2622-98 D2622-05 (“Standard Test Method for Sulfur in Petroleum
Products by Wavelength Dispersive X-Ray Fluorescence Spectrometry”).
503.13 ASTM D2880-96 Standard Specification for Gas Turbine Fuel Oils
503.14 503.13 ASTM D4294-02 or D4294-03 (“Standard Test Method for Sulfur in Petroleum and
Petroleum Products by Energy-Dispersive X-Ray Fluoresence Spectroscopy
Fluorescence Spectrometry”).
503.15 503.14 ASTM D5504-01 or D5504-08 (“Standard Test Method for Determination of Sulfur
Compounds in Natural Gas and Gaseous Fuels by Gas Chromatography and
Chemiluminescence”).
504.16 503.15 South Coast Air Quality Management District Method 307-94 307-91
(“Determination of Sulfur in a Gaseous Matrix”), revised 1994.
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Return to list of attachments
MARICOPA COUNTY
AIR POLLUTION CONTROL REGULATIONS
REGULATION III – CONTROL OF AIR CONTAMINANTS
RULE 324
STATIONARY RECIPROCATING INTERNAL COMBUSTION ENGINES (RICE)
INDEX
SECTION 100 – GENERAL
101 PURPOSE
102 APPLICABILITY
103 EXEMPTIONS
104 PARTIAL EXEMPTIONS FOR EMERGENCY ENGINES
105 PARTIAL EXEMPTIONS FOR LOW USAGE NON-EMERGENCY ENGINES
106 PARTIAL EXEMPTION FOR NONROAD ENGINES
107 PARTIAL EXEMPTION FOR NON-EMERGENCY ENGINES THAT ARE
LOCATED AT A MAJOR SOURCE OF NITROGEN OXIDES (NOX)
108 PARTIAL EXEMPTION FOR STATIONARY RICE THAT ARE LOCATED
AT A NUCLEAR POWER PLANT
SECTION 200 – DEFINITIONS
201 AFTERCOOLER/INTERCOOLER
202 ALTERNATIVE FUELS
203 COGENERATION UNIT
204 COMMISSIONING PERIOD
205 COMPRESSION-IGNITION ENGINE
206 EMERGENCY ENGINE
207 GASOLINE
208 IDENTICAL REPLACEMENT ENGINE
209 LEAN-BURN ENGINE
210 LIQUEFIED PETROLEUM GAS (LPG)
211 LOCATION
212 LOW SULFUR OIL
213 NATURAL GAS
214 NON-EMERGENCY ENGINE
215 PARTS PER MILLION BY VOLUME DRY (PPMVD)
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216 RATED BRAKE HORSEPOWER (RATED BHP)
217 RECONSTRUCTED
218 RICH-BURN ENGINE
219 SPARK-IGNITION ENGINE
220 STATIONARY RECIPROCATING INTERNAL COMBUSTION ENGINE
(RICE)
221 SULFUR OXIDES (SOX)
222 ULTRA LOW SULFUR OIL
223 WASTE DERIVED FUEL GAS
SECTION 300 – STANDARDS
301 FUEL REQUIREMENTS
302 MAINTENANCE REQUIREMENTS
303 LIMITATIONS FOR STATIONARY RICE - OPACITY
304 LIMITATIONS FOR NON-EMERGENCY ENGINES
305 IDENTICAL REPLACEMENT ENGINE
306 NON-RESETTING TOTALIZING HOUR METER
SECTION 400 – ADMINISTRATIVE REQUIREMENTS
401 COMPLIANCE SCHEDULE-STATIONARY RICE BEING REMOVED FROM
SERVICE
402 COMPLIANCE SCHEDULE-NON-RESETTING TOTALIZING HOUR
METER
403 COMPLIANCE SCHEDULE-ENGINES AT A SOURCE THAT BECOMES A
MAJOR SOURCE
SECTION 500 – MONITORING AND RECORDS
501 COMPLIANCE DETERMINATION
502 RECORDKEEPING/RECORDS RETENTION
503 COMPLIANCE DETERMINATION-TEST METHODS INCORPORATED BY
REFERENCE
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Adopted 10/22/2003; Revised 10/17/2007; Revised 11/02/2016; Revised MM/DD/YYYY
MARICOPA COUNTY
AIR POLLUTION CONTROL REGULATIONS
REGULATION III – CONTROL OF AIR CONTAMINANTS
RULE 324
STATIONARY RECIPROCATING INTERNAL COMBUSTION ENGINES (RICE)
SECTION 100 – GENERAL
101 PURPOSE: To limit carbon monoxide (CO), nitrogen oxides (NOX), sulfur oxides (SOX),
volatile organic compounds (VOCs), and particulate matter (PM) emissions from stationary
reciprocating internal combustion engines (RICE).
102 APPLICABILITY:
102.1 This rule applies to:
a. Any stationary RICE, including stationary RICE used in cogeneration, with a
rated brake horsepower (rated bhp) of greater than 125, if the stationary RICE is
not located at a major source of NOX emissions;
b. Any stationary RICE, including stationary RICE used in cogeneration, with a
rated bhp of more than 50 if the stationary RICE is not located at a major source
of NOX emissions and the maximum aggregated rated bhp of all stationary RICE
at the stationary source is more than 125 when all engines with a rated bhp of
more than 50 are aggregated;
c. Any stationary RICE, including stationary RICE used in cogeneration, with a
rated brake horsepower (rated bhp) of greater than 50, if the stationary RICE is
located at a major source of NOX emissions; and
d. Any nonroad engine, with a rated bhp of greater than 125, that is located at a
stationary source that emits or has the potential to emit any regulated air
pollutant greater than the permitting thresholds defined in Rule 100 of these
rules. For the purpose of this Rule, a nonroad engine is any internal combustion
engine that by itself or in or on a piece of equipment is portable or transportable,
meaning designed to be and capable of being carried or moved from one
location to another. Indicia of transportability include but are not limited to,
wheels, skids, carrying handles, dollies, trailers, or platforms.
102.2 NSPS: In addition to this rule, a stationary RICE may be subject to New Source
Performance Standards (NSPS) in Rule 360 of these rules.
102.3 NESHAP: In addition to this rule, a stationary RICE may be subject to National
Emission Standards for Hazardous Air Pollutants (NESHAP) in Rule 370 of these
rules.
103 EXEMPTIONS: The following types of stationary RICE are exempt from all of the
requirements of this rule but shall comply with Rule 300 (Visible Emissions) of these rules:
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103.1 A stationary RICE used directly and exclusively for engine research including engine
development, and subsequent engine performance verification for the purpose of
either engine emission control techniques or engine efficiency improvements.
103.2 A non-emergency engine when it is operated by a manufacturer or distributor of
such equipment for the purpose of performance verification and testing at the
production facility.
103.3 A compressed gas stationary RICE used for solar testing and research programs.
103.4 A stationary RICE test stand used for evaluating engine performance.
104 PARTIAL EXEMPTIONS FOR EMERGENCY ENGINES: A stationary RICE
operated as an emergency engine, as defined in this rule, for any of the following reasons
shall be exempt from Sections 304, 501.1, 501.2, 501.3, and 501.4 of this rule when:
104.1 Used only for power when normal power service fails from the serving utility or if
onsite electrical transmission or onsite power generation equipment fails.
104.2 Used only for the emergency pumping of water resulting from a flood, fire, lightning
strikes, police action or for any other essential public services which affect public
health and safety.
104.3 Used for lighting airport runways.
104.4 Used for sewage overflow mitigation and/or prevention.
104.5 Used for reliability-related activities such as engine readiness, calibration, or
maintenance or to prevent the occurrence of an unsafe condition during electrical
system maintenance, as long as the total number of hours of the operation for these
purposes does not exceed 100 hours per calendar year per engine as evidenced by an
installed non-resetting totalizing hour meter. For the purposes of this rule, hours of
operation during the commissioning period do not count towards the 100 hour per
calendar year limit on hours of operation for reliability-related activities.
104.6 Used as the non-emergency engine when the non-emergency engine has failed, but
only for such time as is needed to repair the non-emergency engine. For the purposes
of this exemption, if the non-emergency engine is not repaired and returned to service
within 12 months, or if the emergency engine is used as the non-emergency engine for
more than 50 hours, whichever occurs first, the emergency engine shall be reclassified
as a non-emergency engine and shall comply with all requirements of this rule that are
applicable to non-emergency engines.
104.7 Used to operate standby emergency water pumps for fire control that activate when
sensors detect low water pressure.
105 PARTIAL EXEMPTIONS FOR LOW USAGE NON-EMERGENCY ENGINES:
The following low usage non-emergency engines onsite and in use before [date of rule
adoption] shall be exempt from Sections 304, 501.1, 501.2, 501.3, 501.4, and 502.6 of this rule:
105.1 Each engine with a rated bhp at or below 1000 that operates less than 200 hours per
calendar year as evidenced by an installed non-resetting totalizing hour meter.
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105.2 Each engine with a rated bhp above 1000 that operates less than 100 hours per
calendar year as evidenced by an installed non-resetting totalizing hour meter.
106 PARTIAL EXEMPTION FOR NONROAD ENGINES: Each nonroad engine shall
comply with Rule 300 of these rules and Section 502.6 of this rule, but shall be exempt from all
other requirements of this rule.
107 PARTIAL EXEMPTION FOR NON-EMERGENCY ENGINES THAT ARE
LOCATED AT A MAJOR SOURCE OF NOX: A non-emergency engine that is located at
a major source of NOX shall not be required to comply with Section 501.2 of this rule during
the five year period beginning on January 1st of the year in which the engine was manufactured,
if the owner or operator provides documentation that the non-emergency engine is certified
by the manufacturer to comply with emission limits in 40 CFR 60 subpart IIII or 40 CFR 60
subpart JJJJ that are more stringent than the applicable emission limit(s) in Table 324-3 of
this rule, and provides documentation that the non-emergency engine is installed, operated,
and maintained in accordance with the manufacturer's specifications.
108 PARTIAL EXEMPTION FOR STATIONARY RICE THAT ARE LOCATED AT
A NUCLEAR POWER PLANT: A stationary RICE that is located at a nuclear power
plant and is operated solely for the following reasons shall comply only with the provisions
in Sections 301, 302, 306, 402, 501.5, 502.1, 502.3, 502.4, and 502.5 of this rule:
108.1 Used for safety reasons and for operational tests required by the Nuclear Regulatory
Commission.
108.2 Used for power when normal power service fails from the serving utility or if onsite
electrical transmission or onsite power generation equipment fails.
108.3 Used for the emergency pumping of water resulting from a flood, fire, lightning
strikes, police action or for any other operation that is essential to public health and
safety.
108.4 Used to initiate operation of onsite emergency power generation equipment.
108.5 Used for reliability-related activities such as engine readiness, calibration, or
maintenance or to prevent the occurrence of an unsafe condition during electrical
system maintenance. Hours of operation for reliability-related activities shall not
exceed 100 hours per year unless the reliability-related activities are recommended or
required by the federal, state, or local government and the owner or operator maintains
records demonstrating that the reliability-related activities are recommended or
required.
SECTION 200 – DEFINITIONS: For the purpose of this rule, the following definitions shall
apply, in addition to those definitions found in Rule 100 (General Provisions and Definitions) of these
rules. In the event of any inconsistency between any of the Maricopa County Air Pollution Control
Rules, the definitions in this rule take precedence.
201 AFTERCOOLER/INTERCOOLER: A system that cools the engine intake air or air/fuel
mixture after the air exits the turbocharger and prior to the introduction into the cylinder,
thereby lowering NOX emissions.
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202 ALTERNATIVE FUELS: Substitutes for oil-derived and fossil-fuel derived fuels,
including but not limited to biodiesel, propane, ethanol or methanol.
203 COGENERATION UNIT: A stationary RICE unit that burns fuel to simultaneously
produce electricity and heat in a single thermodynamic process and is usually located in close
proximity to the equipment requiring the heat energy.
204 COMMISSIONING PERIOD: The final phase of the stationary RICE construction process
during which all mechanical, electrical, and control systems for the RICE and all related
equipment are checked, and all performance measures specified in the purchase agreement are
confirmed. For the purposes of this rule, a stationary RICE may not be used for its intended
purpose or any other beneficial use during the commissioning period. If a non-emergency
engine subject to this rule is also subject to a condition in a Maricopa County Air Quality Permit
limiting total hours of operation, the hours of operation during the commissioning period shall
be included when determining compliance with the permitted limit on total hours of operation.
205 COMPRESSION-IGNITION ENGINE: A stationary RICE with operating characteristics
wherein the principal mechanism of igniting the fuel and air mixture in the cylinders is the
compression of air in the cylinder until it is so hot that any fuel injected into the air or mixed
with the air ignites. In this type of engine, a separate ignition source, such as a spark plug, is not
used.
206 EMERGENCY ENGINE: A stationary RICE that meets all of the following criteria:
206.1 Is operated solely for any of the reasons listed in Section 104 of this rule;
206.2 Does not exceed 500 hours of operation per any twelve consecutive months, including
the 100 hours per calendar year listed in Section 104.5 of this rule and including any
hours of operation that occur during the commissioning period; and
206.3 Is not operated to supply standby power due to a voluntary reduction in power by a
utility or power company, or to supply power for distribution or sale to the grid, or to
supply power at a source in order to avoid peak demand charges or high electric
energy prices during on-peak price periods.
207 GASOLINE: Any fuel sold in any State for use in motor vehicles and motor vehicle
engines, or nonroad or stationary engines, and commonly or commercially known or sold as
gasoline.
208 IDENTICAL REPLACEMENT ENGINE: A stationary RICE that is substituted for
another stationary RICE that is intended to perform the same or similar function as the original
stationary RICE and where all of the following conditions exist:
208.1 The identical replacement engine results in equal or lower air contaminant emissions
than the original stationary RICE; and
208.2 The identical replacement engine meets the emission control technology standards
contained in Section 304 of this rule; and
208.3 The identical replacement engine has the same manufacturer type, model number, and
manufacturer’s rated bhp as the original stationary RICE.
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209 LEAN-BURN ENGINE: A spark-ignition engine with an air-to-fuel operating range that
has more air present than is needed to burn the fuel present and cannot be adjusted to
operate with an exhaust oxygen concentration of less than or equal to 2%.
210 LIQUEFIED PETROLEUM GAS (LPG): Any liquefied hydrocarbon gas obtained as a
by-product in petroleum refining or natural gas production.
211 LOCATION: Any single site at a building, structure, facility or installation.
212 LOW SULFUR OIL: Fuel oil containing less than or equal to 0.05% sulfur by weight.
213 NATURAL GAS: A naturally occurring mixture of hydrocarbon and non-hydrocarbon
gases found in geologic formations beneath the Earth’s surface, of which the principal
constituent is methane.
214 NON-EMERGENCY ENGINE: A stationary RICE that is not an emergency engine.
215 PARTS PER MILLION BY VOLUME DRY (PPMVD): A unit of proportion used to
express concentration that is corrected to a dry basis.
216 RATED BRAKE HORSEPOWER (RATED BHP): The maximum brake horsepower
(bhp) specified by the engine manufacturer for the engine application, usually listed on the
nameplate of the engine. If the engine has been altered so that the maximum brake
horsepower is different than the rated brake horsepower on the nameplate, then the maximum
brake horsepower shall be considered the rated brake horsepower.
217 RECONSTRUCTED: Repairs, changes, or improvements to a stationary RICE where the
fixed capital cost of the new and refurbished engine components exceeds 75% of the fixed
capital cost of purchasing an entirely new engine with the same brake horsepower rating; or
construction of an engine on a previously used engine block if the engine is constructed using
all new components except for the engine block. For the purposes of this rule, the cost of
installing emission controls (such as a diesel particulate filter, a three-way catalyst, or a selective
catalytic reduction system) is not included when determining whether or not an engine has
been reconstructed.
218 RICH-BURN ENGINE: A spark-ignition engine that is not a lean-burn engine.
219 SPARK-IGNITION ENGINE: A stationary RICE wherein the fuel is usually mixed with
intake air before introduction into the combustion chamber resulting in a relatively
homogeneous air/fuel mixture in the combustion chamber, at which time a spark plug, or
other device, then ignites the air/fuel mixture.
220 STATIONARY RECIPROCATING INTERNAL COMBUSTION ENGINE
(RICE): A reciprocating, piston-driven internal combustion engine that is operated or
intended to be operated at one specific location for more than 12 consecutive months or
that is attached to a foundation at the location. An engine that replaces an engine at a
location and is intended to perform the same or similar function as the engine being replaced
will be included in calculating the consecutive time period. A stationary RICE is not a
nonroad engine.
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221 SULFUR OXIDES (SOX): Oxides of sulfur calculated as equivalent sulfur dioxide.
222 ULTRA LOW SULFUR OIL: Fuel oil containing less than or equal to 0.0015% sulfur by
weight.
223 WASTE DERIVED FUEL GAS: A gaseous fuel that is generated from the biodegradation
of solid or liquid waste including, but not limited to, digester gas and landfill gas.
SECTION 300 – STANDARDS:
301 FUEL REQUIREMENTS: An owner or operator of a stationary RICE that meets the
criteria listed in Section 102 of this rule shall comply with one of the following:
301.1 Use ultra low sulfur oil, except as provided in Sections 301.1a or 301.1b of this rule.
a. Engines that are not subject to the 40 CFR 60 Subpart IIII or 40 CFR 63
Subpart ZZZZ may use existing low sulfur oil purchased (or otherwise obtained)
prior to November 2, 2016 until depleted.
b. Engines that are subject to 40 CFR 60 Subpart IIII or 40 CFR 63 Subpart ZZZZ
must also comply with the fuel requirements in the applicable subpart.
301.2 Use any waste derived fuel gas that contains no more than 0.08% sulfur by weight,
alone or in combination with other fuels.
301.3 Use gasoline that meets the sulfur standard of 80 ppm as a per-gallon cap.
301.4 Use natural gas, liquefied petroleum gas (LPG), or any alternative fuel that contains no
more than 0.05% sulfur by weight, alone or in combination with other fuels.
302 MAINTENANCE REQUIREMENTS: An owner or operator of a stationary RICE shall
maintain the stationary RICE in accordance with the manufacturer's written instructions or
in accordance with the maintenance schedule provided by the manufacturer’s authorized
service provider. Alternatively, the owner or operator shall conduct preventative
maintenance according to the following schedule, including all of the following tuning
procedures, if the engine is so equipped, and if such procedures are appropriate to the type
of engine.
302.1 The following maintenance procedures shall be completed no less frequently than
every 300 hours of operation (for engines that operate 300 hours per year or more)
or at least once every 12 months (for engines that operate less than 300 hours per
year):
a. Clean the inlet air filter (if so equipped);
b. Change oil filter; and
c. Change the lubricating oil or conduct an oil analysis to determine Total Base
Number, viscosity, and percent water content. The lubricating oil must be
replaced within 2 business days after the analytical results are received if any of
the following condemning limits are exceeded:
(i) Total Base Number is less than 30% of the Total Base Number of the oil
when new;
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(ii) Viscosity of the oil has changed by more than 20 percent from the viscosity
of the oil when new; or
(iii) Percent water content (by volume) is greater than 0.5.
302.2 The following maintenance procedures shall be completed no less frequently than
every 1,000 hours of operation (for engines that operate 1,000 hours per year or
more) or at least once every 12 months (for engines that operate less than 1,000
hours per year):
a. Replace the inlet air filter;
b. Clean all fuel filters (except cartridge type fuel filters);
c. Replace cartridge type fuel filters;
d. Check and adjust the intake and exhaust valves;
e. Check and adjust the spark plugs (if so equipped);
f. Check and adjust the spark timing and dwell or fuel injection timing (if
adjustable); and
g. Check and adjust the carburetor mixture (if adjustable).
302.3 The following maintenance procedures shall be completed no less frequently than
every 3,000 hours of operation (for engines that operate 3,000 hours per year or
more) or at least once every 12 months (for engines that operate less than 3,000
hours per year):
a. Replace spark plugs and ignition points (if so equipped);
b. Change coolant (if so equipped); and
c. Check the exhaust system and repair all leaks and/or restrictions.
303 LIMITATIONS FOR STATIONARY RICE – OPACITY: An owner or operator of a
stationary RICE shall not discharge into the ambient air from any such engine any air
contaminant, other than uncombined water, in excess of 20% opacity.
304 LIMITATIONS FOR NON-EMERGENCY ENGINES:
304.1 Requirements for Non-Emergency Compression-Ignition Engines That Are
Not Located At A Major Source of NOX: An owner or operator of a non-
emergency compression-ignition engine that is rated above 250 bhp and is not
located at a major source of NOX shall comply with the engine requirements in Table
324-1, as applicable, depending on the date the engine was manufactured or
reconstructed (whichever occurred later) and the rated brake horsepower of the
engine:
TABLE 324-1
MANUFACTURED OR
RECONSTRUCTED RATED BHP ENGINE REQUIREMENTS*
770 ppmvd or 10 g/bhp-hr NOX or
turbocharger with
Prior to October 22, 2003 250-399 aftercooler/intercooler or
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TABLE 324-1
MANUFACTURED OR
RECONSTRUCTED RATED BHP ENGINE REQUIREMENTS*
4-degree injection timing delay
550 ppmvd or 7.2 g/bhp-hr NOX or
turbocharger with
aftercooler/intercooler or
Prior to October 22, 2003 More than 399 4-degree injection timing delay
530 ppmvd or 6.9 g/bhp-hr NOX;
1,000 ppmvd CO;
On or after October 22, 2003 More than 250 0.40 g/bhp-hr PM
* ppmvd emission standards are corrected to 15% oxygen.
304.2 Requirements for Non-Emergency Spark-Ignition Engines That Are Not
Located At A Major Source of NOX: An owner or operator of a non-emergency
spark-ignition engine that is rated above 250 bhp and is not located at a major source
of NOX shall comply with the engine requirements in Table 324-2, as applicable,
depending on the date the engine was manufactured or reconstructed (whichever
occurred later) and whether it is a lean-burn or rich-burn engine:
TABLE 324-2
LEAN-BURN ENGINES
MANUFACTURED
OR
RECONSTRUCTED NOX** VOC** CO**
280 ppmvd or 4.0 800 ppmvd or 5.0 4,500 ppmvd
Prior to October 22, g/bhp-hr g/bhp-hr or three-way
2003 or three-way catalyst* or three-way catalyst* catalyst*
On or after October 22, 110 ppmvd or 1.5
2003 g/bhp-hr Not Applicable 4,500 ppmvd
RICH-BURN ENGINES
MANUFACTURED
OR
RECONSTRUCTED NOX** VOC** CO**
280 ppmvd or 4.0 800 ppmvd or 5.0
Prior to October 22, g/bhp-hr or three-way g/bhp-hr or three- 4,500 ppmvd or
2003 catalyst* way catalyst* three-way catalyst*
On or after October 22, 20 ppmvd or 0.30
2003 g/bhp-hr Not Applicable 4,500 ppmvd
* The three-way catalyst shall provide a minimum of 80% control efficiency for NOX and CO for engines fueled with
natural gas, propane or gasoline. In addition, the three-way catalyst shall also provide a minimum of 50% control
efficiency for VOC for engines fueled by gasoline.
** ppmvd emission standards are corrected to 15% oxygen.
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304.3 Emission Limits for Non-Emergency Engines That Are Located At A Major
Source of NOX: An owner or operator of a non-emergency engine that is rated
above 50 bhp and is located at a major source of NOX shall comply with the engine
requirements in Table 324-3, as applicable, depending on the engine type:
TABLE 324-3
ENGINE TYPE NOX* VOC* CO* PM
110 ppmvd or 800 ppmvd or Not
Spark-Ignition Lean-Burn 1.5 g/bhp-hr 5.0 g/bhp-hr 4,500 ppmvd Applicable
20 ppmvd or 800 ppmvd or Not
Spark-Ignition Rich-Burn 0.30 g/bhp-hr 5.0 g/bhp-hr 4,500 ppmvd Applicable
530 ppmvd or Not
Compression-Ignition 6.9 g/bhp-hr Applicable 1,000 ppmvd 0.40 g/bhp-hr
* ppmvd emission standards are corrected to 15% oxygen.
305 IDENTICAL REPLACEMENT ENGINE: An identical replacement engine shall be
treated as the original stationary RICE that it replaces for the purposes of compliance with this
rule.
306 NON-RESETTING TOTALIZING HOUR METER: The owner or operator of a
stationary RICE, except for those engines being removed from service under Section 401 of
this rule, shall install and operate a non-resetting totalizing hour meter. If the non-resetting
totalizing hour meter is found to be malfunctioning, the owner or operator shall:
306.1 Record hours of operation daily until the function of the hour meter is restored; and
306.2 Restore the function of the hour meter within two weeks. Or, if it is not possible to
restore the function of the hour meter within two weeks, the owner or operator shall
notify the Control Officer in writing and provide a schedule for restoration of the
function of the hour meter.
SECTION 400 – ADMINISTRATIVE REQUIREMENTS
401 COMPLIANCE SCHEDULE-STATIONARY RICE BEING REMOVED FROM
SERVICE: If a stationary RICE must be removed from service because such engine does
not comply with the emission limits listed in Section 300 of this rule, then the stationary
RICE shall be removed from service no later than [insert date one year after rule adoption].
The stationary RICE that replaces such engine shall comply with all applicable provisions of
this rule upon installation.
402 COMPLIANCE SCHEDULE-NON-RESETTING TOTALIZING HOUR
METER: The owner or operator of a stationary RICE that is not equipped with a non-
resetting totalizing hour meter on [insert date of rule adoption], and is not being removed
from service under Section 401 of this rule, shall install and operate a non-resetting totalizing
hour meter on each such engine no later than [insert date one year after rule adoption].
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403 COMPLIANCE SCHEDULE-ENGINES AT A SOURCE THAT BECOMES A
MAJOR SOURCE: If a non-emergency engine is located at a source that becomes a major
source of nitrogen oxides after [insert date of rule adoption], the owner or operator shall
demonstrate compliance with the emission limits in Table 324-3 within one year after the
source becomes a major source of nitrogen oxides.
SECTION 500 – MONITORING AND RECORDS
501 COMPLIANCE DETERMINATION:
501.1 Non-Emergency Engines That Are Not Located At A Major Source of NOX:
An owner or operator of a non-emergency engine which is subject to the
requirements in Section 304.1 or 304.2 of this rule shall demonstrate compliance
using one of the following methods, as applicable:
a. Provide documentation that the stationary RICE is certified by the manufacturer
to comply with emission limits in 40 CFR 60 Subpart IIII or 40 CFR 60 Subpart
JJJJ that are more stringent than the applicable emission limits in Table 324-1 or
324-2 of this rule, and provide documentation that the engine is installed,
operated, and maintained in accordance with the manufacturer's specifications.
b. Conduct a performance test in accordance with Section 501.4 of this rule at least
once every 5 years. The performance test shall demonstrate compliance with one
of the following requirements:
(1) The applicable emission limits in units of grams per brake horsepower-hour
(g/bhp-hr); or
(2) The applicable emission limits in units of ppmvd; or
(3) The three-way catalyst provides a minimum of 80% control efficiency for
NOX and CO for engines fueled with natural gas, propane or gasoline, and
the three-way catalyst also provides a minimum of 50% control efficiency for
VOC for engines fueled by gasoline.
c. Provide documentation that the non-emergency compression-ignition engine
was manufactured or reconstructed (whichever occurred later) prior to October
22, 2003 and provide documentation that the non-emergency compression-
ignition engine is equipped with a turbocharger with an aftercooler/intercooler.
d. Provide documentation that the non-emergency compression-ignition engine
was manufactured or reconstructed (whichever occurred later) prior to October
22, 2003 and:
(1) Provide documentation that the injection timing has been set at 4 degrees
below the factory setting for the engine. Written verification of the factory
set timing, along with documentation that the engine timing has been delayed
by 4 degrees must be submitted; or
(2) Provide documentation that the injection timing has been set at 4 degrees
below the manufacturer's standard timing of the engine. Written verification
of the manufacturer's standard timing of the engine prior to tuning for NOX
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control, along with documentation that the timing has been delayed by 4
degrees must be submitted; or
(3) Provide documentation that the injection timing has been set at 16 degrees
below top dead center or less (if information regarding the manufacturer's
standard timing or factory set timing is not available).
501.2 Non-Emergency Engines That Are Located At A Major Source of Nitrogen
Oxides: An owner or operator of a non-emergency engine which is subject to
emission limits in Section 304.3 of this rule shall demonstrate compliance by
conducting a performance test in accordance with Section 501.4 of this rule at least
once every 2 years. The performance test shall demonstrate compliance with the
applicable emission limits in units of grams per brake horsepower-hour (g/bhp-hr)
or ppmvd.
501.3 Representative Performance Testing: An owner or operator may demonstrate
compliance with the applicable emission limits or control efficiency requirements in
Table 324-1, Table 324-2, or Table 324-3 of this rule by conducting representative
performance testing in accordance with Section 501.4 of this rule, provided all of the
following requirements are satisfied:
a. The engines are located at the same stationary source;
b. The engines were produced by the same manufacturer, have the same model
number or other manufacturer's designation in common, and have the same
rated capacity and operating specifications;
c. The engines are operated and maintained in a similar manner;
d. At least one engine or one third of the engines in the specified group, whichever
is greater, are tested each time a performance test is required;
e. Each time a performance test is required, different engines are tested so that all
engines in the specified group are tested before any engines in the representative
group are retested; and
f. If emissions from any engine in the specified group exceed an applicable
emission limit, or if the control efficiency for any pollutant controlled by a three-
way catalyst is lower than the required control efficiency, the owner or operator
shall demonstrate that each engine in the specified group is in compliance with
the applicable limits by conducting a performance test on each engine in the
specified group.
501.4 Performance Test Conditions: Performance tests shall be conducted using the test
methods listed in Section 503 of this rule. Testing for stationary RICE shall be
completed at either the maximum operating load or no less than 80% of the rated bhp.
If the owner or operator of an engine demonstrates to the Control Officer that the
engine cannot operate at these conditions, then emissions source testing shall be
performed at the highest achievable continuous rated bhp or under the typical duty
cycle or typical operational mode of the engine. The result of the performance test
shall be the arithmetic mean of the results of three test runs. Each test run shall have a
minimum sample time of one hour.
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501.5 Fuel-Sulfur Verification: The owner or operator of an engine fueled with gasoline
shall submit documentation that gasoline was purchased within the United States.
The owner or operator of an engine fueled with diesel, natural gas, LPG, or an
alternative fuel shall submit one of the following documents listing the accurate
sulfur content of the fuel based on enforceable test methods as approved by the
Administrator to determine the sulfur content:
a. Fuel receipts, or
b. Contract specifications, or
c. Pipeline meter tickets, or
d. Fuel supplier information, or
e. Purchase records, or
f. Test results of the fuel for sulfur content.
501.6 Waste Derived Fuel Gas - Sulfur Verification: The owner or operator shall
submit documentation of the sulfur content of the waste derived fuel gas to the
Control Officer upon request. The sulfur content of gaseous fuels shall be
determined by South Coast Air Quality Management District Method 307-91
Determination of Sulfur in a Gaseous Matrix.
502 RECORDKEEPING/RECORDS RETENTION: The owner or operator of a stationary
RICE subject to this rule shall comply with the following requirements and retain records for
at least 5 years:
502.1 Stationary RICE List: Maintain a list of stationary RICE that includes all of the
following information for each stationary RICE: combustion type (compression-
ignition, or lean-burn spark-ignition, or rich-burn spark-ignition); manufacturer; model
designation, rated bhp, serial number, and the location of each engine at the facility. If
the equipment list associated with the current permit includes all of the required
information for each stationary RICE located at the facility, this requirement may be
fulfilled by keeping a complete copy of the current permit, including the equipment
list, in a readily accessible location at the facility where the engines are located, and by
providing the equipment list to the Control Officer upon request.
502.2 Operation Records: An owner or operator of a stationary RICE shall maintain
records of the monthly and 12-month rolling total hours of operation for each
stationary RICE. For emergency engines, the operation records shall also include:
a. Monthly and annual hours of operation for reliability related activities such as
engine readiness, calibration, or maintenance, or to prevent the occurrence of an
unsafe condition during electrical system maintenance; and
b. The number of operating hours for emergency use and an explanation for the
emergency use.
502.3 Maintenance Records: An owner or operator of a stationary RICE shall maintain
records of all stationary RICE maintenance (including the date when maintenance was
performed and the maintenance procedures that were performed). If an owner or
operator of a non-emergency engine demonstrates compliance with the requirements
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in Section 304.1 of this rule using the method specified in Section 501.1(d) of this rule,
the maintenance record shall include documentation of the injection timing setting
each time maintenance is performed on the stationary RICE. In addition, one of the
following documents shall be available at all times at the facility where the stationary
RICE is located:
a. The manufacturer’s written instructions for operation and maintenance of each
stationary RICE;
b. A written maintenance schedule provided by the manufacturer’s authorized service
provider; or
c. A written maintenance plan indicating which of the tuning procedures listed in
Section 302 of this rule are applicable to each stationary RICE.
502.4 Fuel Records:
a. Maintain records of the type and amount of fuel purchased for use in the
stationary RICE (e.g. receipts, pipeline tickets, or bills of lading); and
b. Maintain records of the sulfur content of any fuel that is used in the stationary
RICE, excluding gasoline. For gasoline, maintain records that the fuel was
purchased in the United States.
502.5 Manufacturer's Operation and Maintenance Instructions: An owner or operator
of an engine that is subject to the requirements of Section 302 of this rule shall keep
the manufacturer's written instructions for operation and maintenance of the engine
available at the facility where the engine is located at all times. If the manufacturer's
written instructions are not available, the owner or operator shall keep a preventative
maintenance plan, indicating which procedures in Section 302 of this rule are
appropriate to the engine, available at the facility where the engine is located at all
times.
502.6 Nonroad Engine Records: An owner or operator of a nonroad engine shall maintain
the following records for each non-road engine:
a. Date that each engine is brought to the stationary source; and
b. For engines located at a stationary source greater than 14 consecutive days:
(1) Make, model, serial number, and rated capacity (bhp hours) of the engine; and
(2) Date of each instance in which the engine is moved from its existing location,
and the reason why the engine was moved; and
(3) Fuel type and sulfur content of the fuel.
503 COMPLIANCE DETERMINATION-TEST METHODS INCORPORATED BY
REFERENCE: The following test methods are approved for use for the purpose of
determining compliance with this rule. The test methods are incorporated by reference in Rule
360 and Appendix G of the Maricopa County Air Pollution Control Regulations. Alternative
EPA-approved test methods may be used upon written approval from the Control Officer.
When more than one test method is permitted for the same determination, an exceedance
under any method will constitute a violation. Copies of test methods referenced in this section
are available at the Maricopa County Air Quality Department.
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503.1 EPA Reference Methods 1 (“Sample and Velocity Traverses for Stationary Sources”)
and 1A (“Sample and Velocity Traverses for Stationary Sources with Small Stacks or
Ducts”) (40 CFR 60, Appendix A).
503.2 EPA Reference Methods 2 (“Determination of Stack Gas Velocity and Volumetric
Flow Rate”), 2A (“Direct Measurement of Gas Volume Through Pipes and Small
Ducts”), 2C (“Determination of Stack Gas Velocity and Volumetric Flow Rate in
Small Stacks or Ducts”), and 2D (“Measurement of Gas Volumetric Flow Rates in
Small Pipes and Ducts”) (40 CFR 60, Appendix A).
503.3 EPA Reference Methods 3 (“Gas Analysis for the Determination of Dry Molecular
Weight”), 3A (“Determination of Oxygen and Carbon Dioxide Concentrations in
Emissions from Stationary Sources (Instrumental Analyzer Procedure"), 3B (“Gas
Analysis for the Determination of Emission Rate Correction Factor or Excess Air”),
and 3C (“Determination of Carbon Dioxide, Methane, Nitrogen and Oxygen from
Stationary Sources”) (40 CFR 60, Appendix A).
503.4 EPA Reference Method 4 (“Determination of Moisture Content in Stack Gases”)
(40 CFR 60, Appendix A).
503.5 EPA Reference Method 5 (“Determination of Particulate Emissions from Stationary
Sources”) (40 CFR 60, Appendix A)
503.6 EPA Reference Method 202 (“Dry Impinger Method for Determining Condensable
Particulate Emissions from Stationary Sources”) (40 CFR 51, Appendix M).
503.7 EPA Reference Methods 7 (“Determination of Nitrogen Oxide Emissions from
Stationary Sources”), 7A (“Determination of Nitrogen Oxide Emissions from
Stationary Sources - Ion Chromatographic Method”), 7B (“Determination of
Nitrogen Oxide Emissions from Stationary Sources – Ultraviolet Spectrophotometry
Method”), 7C (“Determination of Nitrogen Oxide Emissions from Stationary
Sources – Alkaline Permanganate/Colorimetric Method”), 7D (“Determination of
Nitrogen Oxide Emissions from Stationary Sources – Alkaline-Permanganate/Ion
Chromatographic Method”), and 7E (“Determination of Nitrogen Oxide Emissions
from Stationary Sources – Instrumental Analyzer Procedure”), (40 CFR 60,
Appendix A).
503.8 EPA Reference Method 9 (“Visual Determination of the Opacity of Emissions from
Stationary Sources”) (40 CFR 60, Appendix A).
503.9 EPA Reference Method 10 (“Determination of Carbon Monoxide from Stationary
Sources”) (40 CFR 60, Appendix A).
503.10 EPA Reference Method 18 (“Measurement of Gaseous Organic Compound
Emissions by Gas Chromatography”) (40 CFR 60, Appendix A).
503.11 EPA Reference Method 25A (“Determination of Total Gaseous Organic
Concentration Using a Flame Ionization Analyzer”) (40 CFR 60, Appendix A).
503.12 ASTM D2622-05 (“Standard Test Method for Sulfur in Petroleum Products by
Wavelength Dispersive X-Ray Fluorescence Spectrometry”).
503.13 ASTM D4294-02 or D4294-03 (“Standard Test Method for Sulfur in Petroleum and
Petroleum Products by Energy-Dispersive X-Ray Fluorescence Spectrometry”).
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503.14 ASTM D5504-01 or D5504-08 (“Standard Test Method for Determination of Sulfur
Compounds in Natural Gas and Gaseous Fuels by Gas Chromatography and
Chemiluminescence”).
503.15 South Coast Air Quality Management District Method 307-91 (“Determination of
Sulfur in a Gaseous Matrix”), revised 1994.
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MARICOPA COUNTY BOARD OF HEALTH MEETING MINUTES
Monday, February 25, 2019 at 1:00 pm
301 W. Jefferson Street, 10th Floor, Phoenix, Arizona 85003
Board of Supervisors Conference Room
President Hughes called the meeting to order at 1:02 p.m. Return to list of attachments
ROLL CALL:
Members Present: Members Not Present:
Don Cassano Kristen Acton
Henri Cournand (via phone)
Robert MacMillan
Andrew Rascón
Nedra Halley
Don Hughes
Debra Baldauff
Bill Gates
Ex-Officio: Max Porter
CALL TO THE PUBLIC:
President Hughes announced that we have speaker slips for anyone wishing to speak on any action items. Speakers will
be called after the item is heard. Each speaker will have 2 minutes to speak.
No speaker slips were received.
President Hughes introduced our newest member to the Board of Health. Mr. Andrew Rascón, District 5 Board of
Supervisor Appointment. Mr. Rascón works for Southwest Center for HIV/AIDS and runs his own non-profit as well.
Welcome and congratulations Mr. Rascón on your appointment as our newest member.
DISCUSSION/ACTION ITEMS
1. Approval of Minutes: President Hughes asked for a motion to approve the BOH finance committee minutes from
the BOH Meeting held on July 23, 2018. Motion was made by Mr. MacMillan to approve the BOH finance committee
minutes as presented. Motion was seconded by Mr. Cassano and all were in favor. The motion passed unanimously.
Approval of Minutes: President Hughes asked for a motion to approve the BOH minutes from the BOH Meeting held
on July 23, 2018. Motion was made by Mr. Cassano to approve the BOH minutes as presented. Motion was seconded
by Ms. Halley and all were in favor. The motion passed unanimously.
2. Approval of FY20 OMB budget request Mr. Scot Pitcairn
Mr. Scot Pitcairn presented Department of Public Health’s budget request for FY2020.
For Fiscal Year 2020 Public Health Department’s total base budget request for this year is $58,150,751, a decrease of 6.2%
from the FY19 Revised budget. This consists of no increase to the General Fund budget, this fund remaining flat and on
target, a 9.8% decrease in the Grant Fund budget, and 1% increase in the Special Revenue Fund budget.
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A summary of our base budget request is as follows:
General Fund $ 12,868,622
Grants Fund 36,271,166
Special Revenue (Fee) Fund 9,010,963
TOTAL $ 58,150,751
Operating Budget
General Fund
The general fund request is shown at target baseline level. No increases are being requested at this time. This is not
intended to imply that all service levels are being adequately met. In order to remain at baseline targets we have budgeted
100% vacancy savings for one division administrator position and our PIO position and have eliminated one program
coordinator position.
Fee Fund
The Fee Fund operating budget is submitted $322,248 below the FY19 Revised budget, reflecting a reduction in the
Childhood Immunization budget that keeps expenditures within anticipated revenues. (This budget will be supplemented
by non-recurring funding).
Grant Fund
The decrease of $4,159,112 in the Grant Fund results from the loss and reduction in several grants, including cuts to WIC,
moving the Ryan White Dental Program to the Ryan White Office, reductions to Healthy Start, and various other grant
losses or reductions.
Non-Recurring Budget
General Fund
The $237,775 in one-time funding in the FY19 budget for the replacement X-Ray equipment at our TB Clinic was removed
from the FY20 budget.
Grant Fund
For FY20 the grant carryover/non-recurring budget is $500,000, an increase of $215,000 over the FY19 budget. This
increase reflects additional carry forward from the Smoke Free Grant and the HPHC (Healthy People Healthy Communities)
integrated IGA grants.
Fee Fund
Following the model used last budget year, we have budgeted funds from our fee fund balance, increasing it from
$593,300 in the current year to $1,000,000 in FY20. Of this amount, $200,000 is budgeted for our policy group. This group
will use these funds for childhood vaccination advocacy and in addressing the opioid epidemic in our county. In addition,
Vital Registration is budgeted $125,000 for expanding the east valley office. The Refugee Medical Assistance Program is
budgeted to use $125,000 since they have run short in funding as a result of the current administration reducing the
number of refugees admitted to the country. The remaining $550,000 is being allocated to address needs in the STD
Control program, Childhood Immunization and other mandated areas.
CSCA and ISF
Last year we requested a review above baseline from the Board of Supervisors due to large deficiencies in our funding.
We are not requesting a review this year but there is a funding gap that the Budget Office and county management are
aware of due to the CSCA and ISF charges placed on the Department. Last year in order to balance our budget, $913,296
was used from our Fee Fund balance and $547,457 was designated from non-departmental funds in the event our indirect
collections were insufficient to cover expenses.
Due to two factors, first the reduction of grant receipts and second the increase over the last several years in CSCA and
Internal Service Charges, our indirect collections are not sufficient to cover our administrative costs, ISF charges and CSCA
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charges combined. Over the past ten years we have internally reduced our administrative staff by 10 positions, saving
over $850,000. However, these reductions have increased the workload on existing staff to the point that we cannot
reduce internally further and still function properly. Our rent is a sizable part of our internal charges but we cannot reduce
that amount unless we are allowed to purchase a facility. Our current lease runs through 2023 and we are not certain
whether we will be able to legally get out of the lease obligation before the lease expires. This shortfall is projected in our
budget at $685,549. The solution to fill this gap is left open for further discussion before our budget recommendation is
finalized.
For this current fiscal year’s budget, the County Budget Office obligated $547,457 for this projected shortfall. We have
held positions and generated vacancy savings with our director’s position to help reduce the use of this commitment, but
those options will probably not exist in the next budget cycle. We also could tap further into our fee fund balance.
Regardless of the solution for this problem, both of these options are only a Band-Aid and will not solve the problem of
uncontrolled escalations of CSCA and ISF charges being pushed into limited grant funds. Further increases in our indirect
rates will only further decrease the delivery of services for mandated and other services that public health is expected to
provide to our community. Therefore, a more viable, longer-term solution needs to be researched.
We should also note with this budget submission that the base-level operating budget is likely unable to handle an
outbreak or emergency should one occur. The two items we see as likely are: 1) measles epidemiology responses and; 2)
the treatment of MDR or XDR Tuberculosis cases.
During this last year our community, along with large parts of the world, have dropped below the required vaccination
rates in our schools to accomplish the herd immunity effect for disease prevention of vaccine preventable diseases. The
most contagious of these is Measles. Measles outbreaks have occurred throughout Europe and other parts of the world
and have occurred in 26 states during 2018. Europe has been fighting this previously contained disease spread for over a
year. During last year, with a 93% vaccination rate (we are just under 95%) European nations had 64,000 cases of the
disease. The main cost of our response will be in the epidemiological tracking of the outbreak; the cost of these can range
from $50,000 to hundreds of thousands of dollars. This is why we have been so active in the work with the state to
decrease the personal exemptions being given out to parents who do not vaccinate their children with the school-required
immunizations. While the financial costs of these outbreaks are staggering, the risk of blindness, hearing impairment,
pneumonia and death (1-2 deaths out of every 1,000 cases) can have drastic consequences for children and families.
The second concern is one that we have seen during the last few budget years but the frequency seems to be escalating.
This is the occurrence of multi-drug resistant (MDR) and extreme drug resistant (XDR) Tuberculosis (TB). This strain of TB
is immune to the normal cost-effective drugs that we use to treat standard cases and requires two other types of drugs
that are extremely expensive. A single case can easily cost between $100,000 and $150,000 over the course of their 18-
month to 24-month treatment, and this does not include any surgically required responses. Non-compliant patients also
incur court costs and isolation costs. We cannot predict the number of cases we will have, but if they do occur we will
need to request additional funds as we have in the past.
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Motion to approve the FY20 OMB budget request for Public Health was made by Ms. Halley, seconded by Mr. Cassano
and all were in favor. The motion passed unanimously
3. Approval of FY20 OMB budget request Mr. Gus Martinez
Mr. Gus Martinez presented Department of Environmental Services’ budget request for FY2020.
FUND 100 (County General Fund)
Requested budget for Fund 100 operating is $247,221 in revenues and $9,459,591 in expenditures.
Revenues
Agency 880 is funded by the County General Fund subsidy. Environmental Services collects enforcement revenue from
non-permitted activities. These fines are associated with violations of the Environmental Health Code by persons and
organizations not subject to obtaining a permit. Requested budgeted revenues remain at $247,221 with no change
between FY2019 adopted and FY2020 requested.
In FY2019 Environmental Services acquired the waste resources department which is tasked with operating the counties
six transfer stations. These transfer stations collects approximately 220K in transfer station fees annually.
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Expenditures
Environmental Services General Fund Agency recommended operating budget expenditures are $9,459,591 or .73%
increase from FY19 adopted.
Requested budget includes a slight increase in the amount of supplies and services by 2% or $103,140 for increased costs
in equipment repairs.
Non-Reoccurring Expenditures
The Departments recommended budget includes non-reoccurring expenses in Fund 100 in the amount of $100,003 for
the following:
 IT Recommendations – $100,003
FUND 505 (County Grant Fund)
Requested budget for Fund 505 operating is $67,198 in revenues and $67,198 in expenditures.
Grant Funds
Agency 881 is a grant from the Food and Drug Administration Department of Health and Human Services. Environmental
Services was awarded the grant on September 10, 2015 in the amount of $67,198 for FY2020. The grant was approved by
the Board of Supervisors on October 21, 2015. The purpose of the grant is to advance conformance with the voluntary
national retail food regulatory program standards. The purpose of the grant is to advance conformance with the voluntary
national retail food regulatory program standards. This grant will serve in assessing foodborne illness risk factors in
Maricopa County and also provide permitted food operations with educational strategies to reduce the occurrence of
foodborne illness risk factors. In Year 2, Environmental Services is providing education to all Environmental Health staff
for implementing Active Managerial Control (AMC) principles during their inspections and train the operators to do the
same (Train the Trainer). This training is based on the results of the survey conducted in Year 1. Also, MCESD will develop
an AMC Toolbox, consisting of guidance documents, templates, logs, videos, and handouts on policies, training, and
verification. These materials will emphasize the shift to a population that learns through the oral and visual delivery of
information. Access to these materials will be streamlined via inspection reports, website design, and other mobile
platforms. AMC will be further incentivized by increasing public awareness of the Department’s voluntary AMC program:
the “Cutting Edge Food Safety Partnership.” Our Department will develop media to showcase Cutting Edge Program
participants.
Revenues
Revenues remain unchanged from FY2019 to FY2020 requested and are mandated by the terms of the grant.
Expenditures
Expenditures remain unchanged from FY2019 to FY2020 recommended and are mandated by the terms of the grant.
FUND 290 (Waste Tire Fund)
Requested budget for Fund 290 operating are $5,825,000 in revenues and $5,825,000 in expenditures.
Revenues
Revenues are received from the State of Arizona to fully cover the expenses to the county. These fees are not directly
collected by the county; they are collected through the purchase of a tire.
Expenditures
The Tire Fund expense budget has increased 14.97% from FY2019 to FY2020 to accommodate the increase tires received
at the tire recycling facility. Year over year, the fund has seen increased costs based on the number of registered vehicles
in Maricopa County.
FUND 506 (Environmental Fee Fund)
Requested budget for Fund 506 operating are $21,012,670 in revenues and $21,001,478 in expenditures.
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Revenues
Requested budgeted revenues for Fund 506 are $21,012,670 or $540,701 (3%) above FY2019 adopted.
Pool, food permitting, and environmental plan review are all experiencing a higher than average permit and plan review
submittals resulting in above budgeted revenue. This is primarily due to an uptick in construction projects as the economy
improves.
As plan review in both the Water and Waste and Environmental Health division’s continue to rise, so do the number of
permits being added. Environmental Services expects these trends to continue through FY2020.
Expenditures
Requested budgeted expenses at $21,001,478 or $599,204 (2.85%) above FY19 adopted. Requested budget includes
overall increase in personnel services by $348,968 or 2% with reductions to personal savings to accommodate the
increased workloads. Supplies and services have been increased by $250,236 due to an increase in central services cost
allocations.
Non-Reoccurring Expenditures
The Departments recommended budget includes non-reoccurring expenses in Fund 506 in the amount of $2,117,426 for
the following:
 Vehicles - $750,000
 Overtime – $125,000
 Rent – $93,954
 Contracting Services - $350,000
 IT Recommendations – $798,472
Motion to approve the FY20 OMB budget request for Environment Health was made by Mr. MacMillan, seconded by
Mr. Cassano and all were in favor. The motion passed unanimously
4. Fee Waiver Applications Ms. Jeannie Taylor
Ms. Jeannie Taylor presented 60 fee waivers for review and consideration of approval. A summary sheet document was
provided.
Motion to approve the 60 fee waivers applications was made by Ms. Halley, seconded by Mr. Cassano and all were in
favor. The motion passed unanimously.
5. Approval of initiation of regulatory change for the following rules: Gregory Verkamp
Kimberly Butler
Gregory Verkamp and Kimberly Butler presented 9 Rules for approval of initiation of regulatory changes. Gregory
explained that all rules are the beginning/initiation process. 8 lf the 9 rules EPA is behind them and will ultimately have
to be approved by the EPA.
A. AQ-2017-002
Rule 321 (Municipal Solid Waste Landfills)
The Maricopa County Air Quality Department (MCAQD) is proposing to revise Rule 321 to reflect the federal municipal
solid waste landfill emission guidelines as promulgated August 29, 2016 and codified at Title 40 (Protection of
Environment) of the Code of Federal Regulations (CFR), Part 60 (Standards of Performance for New Stationary Sources),
Subpart Cf (Emission Guidelines and Compliance Times for Municipal Solid Waste Landfills). In addition, the MCAQD is
proposing to incorporate changes recommended by stakeholders, and to make other changes to improve and clarify the
rule.
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Motion to approve Rule 321 (Municipal Solid Waste Landfills) was made by Ms. Halley, seconded by Mr. MacMillan
and all were in favor. The motion passed unanimously.
B. AQ-2017-007
Rule 322 (Power Plant Operations)
Rule 323 (Fuel Burning Equipment from Industrial/Commercial/Institutional Sources)
Rule 324 (Stationary Reciprocating Internal Combustion Engines)
The MCAQD is proposing to revise Rules 322, 323, and 324 to address rule approvability comments provided by the
Environmental Protection Agency (EPA). These changes are required in order for the EPA to approve these rules as
Reasonably Available Control Technology (RACT) for control of nitrogen oxides, which are precursors to ozone formation.
The MCAQD is also proposing changes to address rule improvement comments provided by the EPA, to incorporate
changes recommended by stakeholders, and to make other changes to improve and clarify the rules.
Motion to approve Rule 322 (Power Plan Operations), Rule 323 (Fuel Burning Equipment from
Industrial/Commercial/Institutional Sources) and Rule 324 (Stationary Reciprocating Internal Combustion Engines) was
made by Mr. Cassano, seconded by Ms. Halley, and all were in favor. The motion passed unanimously.
C. AQ-2017-009
Rule 350 (Storage and Transfer of Organic Liquids (Non-Gasoline) at an Organic Liquid Distribution Facility)
Rule 351 (Storage and Loading of Gasoline at Bulk Gasoline Plants and Bulk Gasoline Terminals)
Rule 353 (Storage and Loading of Gasoline at Gasoline Dispensing Facilities)
MCAQD is proposing to revise Rules 350, 351, and 353 to address rule approvability comments provided by the
Environmental Protection Agency (EPA). These changes are required in order for the EPA to approve these rules as
Reasonably Available Control Technology (RACT) to reduce volatile organic compound (VOC) emissions. The MCAQD is
also proposing changes to address rule improvement comments provided by the EPA, to incorporate changes
recommended by stakeholders, and to make other changes to improve and clarify the rules.
Motion to approve Rule 350 (Storage and Transfer of Organic Liquids (Non-Gasoline) at an Organic Liquid Distribution
Facility), Rule 351 (Storage and Loading of Gasoline at Bulk Gasoline Plants and Bulk Gasoline Terminals) and Rule 353
(Storage and Loading of Gasoline at Gasoline Dispensing Facilities) was made by Mr. MacMillan, seconded by Mr.
Cassano and all were in favor. The motion passed unanimously.
D. AQ-2017-010
Rule 210 (Title V Permit Provisions)
The MCAQD is proposing to revise the MCAQD’s NSR rules in order to secure their approval as part of the State
Implementation Plan (SIP) under the federal Clean Air Act. The MCAQD’s NSR rulemaking is comprised of seven (7) rules,
including Rule 210. All of the NSR rules, with the exception of Rule 210, were approved for the initiation of regulatory
change by the Board of Health at the July 23, 2018 meeting. Rule 210 was not initiated at that time because revisions to
the rule were not anticipated. However, upon review of the U.S. Environmental Protection Agency’s (EPA’s)
recommendations, the MCAQD is requesting approval for the initiation of regulatory change in order to revise Rule 210.
Motion to approve Rule 210 (Title V Permit Provisions) was made by Mr. Cassano, seconded by Dr. Baldauff and all
were in favor. The motion passed unanimously.
E. AQ-2017-011
Rule 204 (Emission Reduction Credits for Use with the Arizona Emissions Bank)
The MCAQD is proposing to revise Rule 204 to add provisions for nontraditional sources of emission reduction credits.
Currently, the rule only allows for the generation, certification and utilization of emission reduction credits from permitted
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sources. Proposed revisions include new provisions for the generation, certification, and utilization of emission reduction
credits from nontraditional sources that use truck stop electrification, electric standby equipped transport refrigeration
units, and electric onsite equipment. Revising the rule will provide additional sources of emission reduction credits that
will allow Maricopa County to move towards attainment of the National Ambient Air Quality Standards while still allowing
industrial growth.
Motion to approve Rule 204 (Emission Reduction Credits for Use with the Arizona Emissions Bank) was made by Mr.
Cassano, seconded by Dr. Baldauff and all were in favor. The motion passed unanimously.
Discussion Items:
1. Public Health Report Max Porter
I. Human Resources
II. Communication
III. Infrastructure
IV. Strategic Planning
V. Programs
VI. Disease Update
VII. Future Topics
Max Porter presented the Director’s Public Health Report.
The budget isn’t quite as depressing as the picture that was presented to you. Yes we have some concerns when it comes
to our indirect balance, the central service cots, the ISF funds (administrative costs) that we’re hit with. This isn’t just a
concern for us, it’s a concern for all grant funded departments or any department that has a grant. Budget office is looking
into it and is looking for a solution. They understand that it’s not sustainable the way it’s going. We are working with
them. We have sufficient funds for this year to get through. We have a year to work through this and get to a solution.
Our department (Public Health) and Human Services are both heavily, heavily grant funded. We are both under the same
Assistant County Manager Lee Ann Bohn. She is dedicated to working through this year to try to find a solution for that
problem. We will get through this year. We will do what we always do and we will have a successful year. I do want you
to be aware that it’s not quite as bleak as the picture would look on paper. We are a viable department and we are doing
some wonderful things.
We are part of the Big Cities Health Coalition. We’re not a city, we’re a county but we are the 3rd largest Health jurisdiction
in the Country behind New York and LA. Majority of Health departments are run through the City organizations
throughout the Country, your large metropolis areas. Back in the 50’s it was consolidated that all to the Counties because
we could consolidate better across city borders if we did it all in one. We’re the 3rd largest. Part of being a part of this Big
Cities Health Coalition it allowed us to go back to the meetings this year and we meet with the head of the CDC. We
explained to them that part of the problem we are seeing in our Health Departments is that you’re (the CDC) is sending
funding from the federal government, majority of our funding comes from the federal government, to the State. The State
dictates how they will meet deliverables which often don’t work for an urban area like we are and rural areas. So the
funding they are sending down is going through another massaging at the State level. The State is taking out administrative
expenses and then it goes down to the County department level and fewer and fewer services after each one of these
things happen are reaching the people. The CDC heard us. So in three months from that meeting we received our first
notice from the CDC that they are sending out instead of a grant a cooperative agreement. It’s a guaranteed receipt of
funds. We will be getting a new addition of 2.5 million dollars directly from the CDC for OPIOID control. The OPIOID
Cooperative Agreement guaranteed funding will hit us in August. We are hoping that this will be a beginning of the way
grant funding will flow to us. It gives us a lot better ability to change direction when a new problem hits us. Rather than
waiting for the State to determine that it is a problem this will give us the ability to change a grant deliverable directly.
We’re hoping that, that will be a good change for the future of the way our funding comes in.
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As part of the director’s report here, the big question that if you don’t have you should have is when are we going to get
a new director? We are moving towards that direction. We have some very viable candidates that are in, we have some
good resumes and we’re doing interviews now. So we are hopeful that by your next meeting you will have a real director
that will be giving you this report. We’re hopeful that someone will be here and if they’re not here we will at least have
the name and date of when they will be here.
Childhood Vaccinations
You’re seeing reports almost daily in the news about childhood vaccinations. There is a huge debate with a large amount
of anti-vaxxers, I shouldn’t say large, there is a loud contingency of anti-vaxxers that are in the community. You have to
remember that we lost our herd immunity with our childhood immunizations.
 The majority of the population understand the importance of immunizations. They understand that they have to
participate if we’re going to protect the entire populous.
 There are also 2-3% can’t get vaccinations, they are people that are under treatment for cancer or they are
immune suppressed.
 The anti-vaxxers make up about 3% and they are extremely loud and they’re campaigning against vaccinations.
 6 bills in legislature
o 3 of the bills could really damage our vaccinations
o The anti-vaxxers are pushing harder and harder to give people personal exemptions for whatever reason.
o With legislation we can’t lobby, all we can do is educate.
o The Arizona Partnership for Immunization (TAPI),
Right now should be our peak of flu season
 H1N1 is hitting again
Congenital Syphilis
 Maricopa County Congenital Syphilis rates have doubled in the last 2 years.
 We have been said to be #1 in the nation, we are actually #5
 By statute – 1st trimester tested, 3rd trimester tested
o While it’s horrible the fix is simple
 Tested at delivery
 AHCCCS is on board
 Physicians reminded to test for syphilis in pregnant women
Community Health Survey
 MaricopaHealthMatters.org
 Why the Health Survey Matters
o Every three years, Maricopa County Department of Public Health, in collaboration with health care
and community partners, conducts a Community Health Survey to develop a deeper understanding
from residents about issues that relate to quality of life, availability of services, physical and mental
health, and more.
o The survey is part of a larger review of community health. This goes beyond individual health to look
at what is affecting the community overall, what health issues are affecting some communities more
than others, and what other factors contribute to those issues.
o This research is supported by Synapse, a collaboration of healthcare partners, and the Health
Improvement Partnership of Maricopa County (HIPMC).
o It is part of a broader review of the community’s health conducted in collaboration with seven
healthcare partners and over one hundred community organizations.
o MCDPH needs this to remain an accredited health department.
o Questions come from the National Association of County and City Health Organizations (NACCHO),
the Institute for Healthcare Improvement (IHI) and MCDPH staff, and are finalized for 2019.
o Data from this survey and the countywide health review are used to target programs, funds, and
attention to health needs with the greatest potential for impact and improvement.
127

 How the Survey is Being Conducted
o Goal is 15,000 surveys countywide with representation from all cities and towns
o Responses will be collected from March 1-May 31, 2019
o Robust outreach plan developed with partner organizations assisting in data collection
 What You Get and How You Can Help
 What you can get
o Access to de-identified data
o More responses will allow for more segmentation in data analysis
 How you can help
o Take the survey as a county resident
o Utilize MCDPH outreach toolkit to share the survey with your personal and professional networks
o Possible partnership with MCDPH epidemiologists to clean and analyze data
Community Health Improvement Plan – Grant Opportunity
 Shared Use - https://www.maricopa.gov/4386/Shared-Use
 Opening doors to physical activity and healthy eating.
 Opportunities for physical activity and access to healthy food are essential for health at all ages and stages
of life.
 Many neighborhoods throughout Maricopa County have limited access to spaces for children, youth, adults,
and seniors to easily choose to be active and to eat more nutritious food.
 By opening doors and expanding access to existing facilities, we can improve health and well-being across the
community.
 Maricopa County Department of Public Health (MCDPH) is offering grant funding up to $5000, per site, to
increase the number of spaces in under-served areas, so those community residents can: play exercise and
take part in recreational activities, grow healthy food and participate in nutrition related activities.
 Goal 100 schools opened
 $100,000 ($1500 - $5000 increments)
 School, Church or any public access
 Grant open until June 30th or until funding is gone
 Interested candidates must submit their response either by mail or email no later than May 31, 2019. For full
details, a copy of the request for quote (RFQ), or to submit a response, please visit: bit.ly/opendoorsgrant
ANNOUNCEMENTS AND CURRENT EVENTS
 Next Meeting – April 22, 2019
ADJOURNMENT: There being no further business, motion to adjourn the meeting was made by Ms. Halley, seconded by
Mr. Cassano and motion was passed unanimously. The meeting was adjourned.
128

Return to list of attachments
April 26th 2021
Board of Health Meeting Minutes
Placeholder
129

Copies of all written and electronic Stakeholder input
From: Suzanne Kennedy <suzanne.kennedy@asu.edu>
Return to list of attachments
Sent: Wednesday, August 22, 2018 9:28 AM
To: Kristi Beck (AQD)
Subject: Rule Meeting Today and Comments on 322, 323, and 324
Hi Kristi,
I have been called into a meeting today and won’t make it to the rule meetings today. I just have a few comments as
follows:
1. Rule 322, Section 501.1 – This rule now requires records of the type and amount of fuel used, sulfur content
and days and hours of operation. I would like to remove the requirement to track days and hours of operation
and that fuel use be required to be tracked monthly. Fuel tracking monthly makes the most sense since invoices
are typically sent monthly (in the case of natural gas). I have been unable to identify a reason to track days and
hours of operation. This information does not appear to be needed to determine compliance.
2. Rule 323, Section 501.1 – This rule contains similar requirements for tracking fuel use and days/hours of
operation. I would like to request the same change as stated above.
3. Rule 324, Section 502.4.a – The hours of operation for emergencies should be specified in this section and
testing, reliability and maintenance hours should be grouped together as non‐emergency hours. Suggested
language is: “Monthly and rolling twelve month total hours of operation, emergency hours of operation, and
non‐emergency hours of operation (including hours for testing, reliability, and maintenance).”
I am so sorry that I won’t make it. Please call me if you have any questions.
Thanks!
Suzanne
Suzanne Kennedy
Associate Director, Environmental Compliance
Environmental, Health, and Safety
Arizona State University
Cell ‐ 602‐460‐8173
Desk – 480‐965‐1893
130

From: Ryan.Sweetwood@aps.com
Sent: Thursday, August 30, 2018 1:42 PM
To: Kristi Beck (AQD)
Cc: Eric.Massey@aps.com; Charles.Spell@aps.com
Subject: Rule 323 Comments
Kristi
I tried submitting through EROP and something with my security is blocking me. I will try again tomorrow but wanted to
make sure I sent this over.
In Maricopa County’s (the County) workshop presentation, the County recommends accepting the more stringent boiler
tuning requirements and suggests requirements based rated capacity and whether or not the source was at a major
source. Concerning the County’s recommendations for altering requirements based on rated capacity of the unit, APS
suggests an alternative. APS has reviewed EPA’s comment and believe EPA was intending to apply RACT to “major
source units” (units emitting 100 tons/yr of NOx) and not a minor source unit at a “major source” as suggested by the
County’s proposed commitment. APS requests that RACT requirements only apply to major source units. Applying a
major source applicability limit would be consistent with EPA’s recommendation with Rule 322.
APS owns a Clayton Boiler rated at 11 MBtu/hr, which emits approximately 25 lbs per year. APS has reviewed the
examples for boiler tuning requirements and find them excessive in some situations for simple and small units. Multiple
items in the referenced boiler tuning requirements could not work for this unit. APS doesn't support more stringent
requirements for the smaller units. At a minimum, there should be language that accommodate the size and design of
the unit.
Thanks,
Ryan Sweetwood
Environmental Air Consultant
Arizona Public Service
400 N. 5th St., Phoenix, AZ 85004, Mail Station 9303
P.O. Box 53999, Phoenix, AZ 85072, Mail Station 9303
Cell (602) 478‐8333
Office (602) 250‐5153
ryan.sweetwood@aps.com
‐‐‐ NOTICE ‐‐‐
This message is for the designated recipient only and may contain confidential, privileged or proprietary information. If
you have received it in error, please notify the sender immediately and delete the original and any copy or
printout. Unintended recipients are prohibited from making any other use of this e‐mail. Although we have taken
reasonable precautions to ensure no viruses are present in this e‐mail, we accept no liability for any loss or damage
arising from the use of this e‐mail or attachments, or for any delay or errors or omissions in the contents which result
from e‐mail transmission.
131

From: Caitlin Brady - MCDOTX <CaitlinBrady@mail.maricopa.gov>
Sent: Wednesday, May 1, 2019 8:22 AM
To: Michelle Mada (AQD); Gregory Verkamp (AQD); Johanna Kuspert (AQD); Kimberly Butler (AQD)
Subject: FW: Online Form Submittal: Citizen Comments
From: noreply@civicplus.com [mailto:noreply@civicplus.com]
Sent: Wednesday, May 1, 2019 8:18 AM
To: Regulatory <regulations@mail.maricopa.gov>
Subject: Online Form Submittal: Citizen Comments
Citizen Comments
Each Regulatory Department is committed to providing opportunities for
stakeholder input regarding the adoption and amendment of all regulatory
requirements. Your input will be collected and forwarded to the appropriate
department. You will receive a written response from the applicable department
within two business days. We appreciate your comments and your time.
Case Number/Rule AQ-2017-007 Rule 324 Stationary Reciprocating Internal
Combustion Engines (RICE)
Department Air Quality
I would like to Other
First Name Jon
Last Name Sherrill
Organization City of Chandler - Environmental Management
City Chandler
Zip 85225
Email jon.sherrill@chandleraz.gov
Phone Number 480-782-2387
Phone Type Work
Would you like someone Yes
to contact you?
132

Comments We recently had several air permit inspections for our general
permits that are for our emergency generators. We have been
having these inspections every other year for our facilities and
not had any major issues during the inspections. Each
generator has a logbook that has a monthly record for the
checks that take place, any operation or other issues that
occur. Historically, these records were used to calculate the 12
month hours of operation to show compliance with permit
conditions. However, during our recent inspections, we were
informed that we had not been keeping a monthly rolling record
of hours and that we needed to begin this for our general
permitted sites. I've reviewed the permit and Rule 324 and
understand that this is required but seems like an unnecessary
effort if we keep a monthly log of hours. The previous 12
months can easily be calculated by taking March 2019 hours
and subtracting March 2018 hours to show the current 12
months of hours of operation. The City of Chandler emergency
generators typically run less than a couple hours a month,
often times even less than a couple hours. The City
understands the permit language and will do what is needed to
maintain compliance. However since our sites have been
inspected frequently and this has not previously been noted nor
has it been noted as a compliance issue. The City believes that
for remote sites that also run very limited hours that the
information needed to determine hours of operation can be
calculated from the on-site logbooks during inspections. Our
emergency generators are typically at unmanned facilities,
have limited use and would require additional effort and
resources to collect and track this information. We hope to see
this requirement addressed through logbook information that is
maintained at each site and not a requirement to create
spreadsheets for each generator (we have over 30 permitted
sites). Since Rule 324 is currently being reviewed and possibly
amended we hope that this issue can be addressed during this
process. We would like to see this section clarified that for
limited use, unmanned sites that the on-site logbook can be
used to determine the 12 month hours of operation.
If applicable, attach Field not completed.
supporting documentation
associated with your
comment.
Email not displaying correctly? View it in your browser.
133

Subject: FW: Follow-Up: Maintenance Requirements for Emergency Generators
From: Carlton, Anne B <Anne.Carlton@aps.com>
Sent: Friday, May 24, 2019 11:09 AM
To: Kristi Beck (AQD) <Kristi.Beck@Maricopa.gov>
Subject: RE: Follow‐Up: Maintenance Requirements for Emergency Generators
Hello Kristi,
First, thank you so much for meeting with us to discuss maintenance related issues with our IC engines!
We have reviewed the language and our operations across our fleet. We are requesting the following change to the
verbiage (see below). We have engines from 15 different manufactures (some are no longer in business) and only use a
single qualified service provider. The use of one contractor to conduct engine is preferred by our Supply Chain because
of the clearance required to work at some of our sites as well as safety hazards associated with our facilities. There are
some service providers that have safety records that prohibit them from working at our sites entirely.
An owner or operator of a stationary RICE shall maintain the stationary RICE in accordance with the manufacturer's
written instructions or in accordance with the written maintenance schedule provided by the manufacturer’s authorized
a qualified service provider. If the manufacturer's written instructions are not available and the manufacturer’s
authorized qualified service provider does not provide a written maintenance schedule, the owner or operator shall
conduct preventative maintenance according to the following schedule, including all of the following procedures, if the
engine is so equipped, and if such procedures are appropriate to the type of engine:
Thank you,
Anne
134

Subject: FW: Stakeholder Workshop Update - Rule 324 (Stationary Reciprocating Internal Combustion
Engines)
From: Tveit, Oddvar <oddvar_tveit@tempe.gov>
Sent: Friday, November 15, 2019 6:30 PM
To: Kristi Beck (AQD) <Kristi.Beck@Maricopa.gov>
Cc: Hoppes, Christina <Christina_Hoppes@tempe.gov>; Mikus, Jeremy <jeremy_mikus@tempe.gov>
Subject: RE: Stakeholder Workshop Update ‐ Rule 324 (Stationary Reciprocating Internal Combustion Engines)
Dear Kristi,
Thanks for the opportunity to provide comments in your chat room during the October 24, 2019 workshop. I notice of
you could not accept a proposed comment [KB‐A30] about changing the term “manufacturer’s authorized service
provider” with the term “qualified service provider” because this is not a recognized term in use by the EPA. We agree
with the commenters concern about the term “authorized service provider” because the term in our opinion raises
proprietary issues related to maintenance documentation provided by engine and/or emergency generator
manufacturers exclusively to authorized dealerships. A regular maintenance provider may have authorizations from
various engine manufacturers but may not be able to get authorizations from for example emergency generator
manufacturers who have their own non‐road engines installed. We suggest you consider alterative options and include
language in Section 302 about “or authorization from a manufacturer of a similar engine type” and “in accordance
with recommendations from the manufacturer of a similar engine type.”
Than You,
Oddvar Tveit
Environmental Quality Specialist
PO Box 5002 Mail Stop 23‐1
Tempe, AZ 85280
(480) 350‐8300
oddvar_tveit@tempe.gov
135

Subject: FW: Online Form Submittal: Citizen Comments
From: noreply@civicplus.com <noreply@civicplus.com>
Sent: Thursday, April 8, 2021 2:18 PM
To: PND Regulatory <PNDRegulatory@maricopa.gov>; Kathy Semder (COA) <Kathy.Semder@Maricopa.Gov>; Andy
Linton (OBM) <Andy.Linton@Maricopa.Gov>; Bill Leal (OBM) <Bill.Leal@Maricopa.Gov>; Kathryn Garcia (OBM)
<Kathryn.Garcia@Maricopa.Gov>; Blanca Caballero (ENV) <Blanca.Caballero@Maricopa.gov>
Subject: Online Form Submittal: Citizen Comments
Citizen Comments
Each Regulatory Department is committed to providing opportunities for
stakeholder input regarding the adoption and amendment of all regulatory
requirements. Your input will be collected and forwarded to the appropriate
department. You will receive a written response from the applicable department
within two business days. We appreciate your comments and your time.
Case Number/Rule AQ-2017-007 Rule 324 Stationary Reciprocating Internal
Combustion Engines (RICE)
Department Air Quality
I would like to Other
First Name Tom
Last Name Ekren
Organization Field not completed.
City Tempe
Zip Field not completed.
Email tom.ekren@asu.edu
Phone Number 6025433632
Phone Type Work
Would you like someone to Yes
contact you?
Comments Hello Scott and Kim,
136

I hope all is well!
I have a few comments for draft Rule 324, which deals
explicitly with non-road engines. I understand the purpose of
tracking non-road engines and the amount of time they are
onsite to ensure there is no circumvention of the rules by using
a non-road engine as a stationary engine.
Unfortunately, the record-keeping requirement can be quite
burdensome for facilities with special events that use non-road
generators for a minimal amount of time. Almost all non-road
generators are brought onto the site and removed in less than
a week, and many within 24 hours. Could there be a timeframe,
such as seven days, that if a non-road engine is brought onsite
for more than seven days, then section 502.6 applies?
Additionally, the serial number requirement in Section 502.6 b.
can be difficult to obtain depending on the situation. Rental
companies will have the make, model, and capacity readily
available for the non-road engines being rented, but not the
specific serial number sent to the site. If the non-road engine is
brought onto the site for a single night event, it can be
challenging to obtain the serial number for an event that lasts
three hours at night.
Thank you for reviewing my comments. If you have any
questions, please do not hesitate to call or email me.
Take care!
Tom Ekren
Environmental Professional
Arizona State University
Safety in the Built Environment
Environmental Health and Safety
University Services Building
1551 S. Rural Road
Tempe, AZ 85281
Campus Mail Code 6412
Phone: 602-543-3632
General OHS Safety Email
safety@asu.edu
Visit EH&S Web Page: http://cfo.asu.edu/ehs
Visit ASU Home Page: http://www.asu.edu/
 please consider the environment before printing this email
137

If applicable, attach Field not completed.
supporting documentation
associated with your
comment. The only file
types supported are MS
Office and Adobe Acrobat.
Email not displaying correctly? View it in your browser.
138

Return to list of attachments
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION IX AIR DIVISION
Technical Support Document
for
EPA’s Rulemaking
for the
Arizona State Implementation Plan
Maricopa County Air Quality Department
Rule 323
Fuel Burning Equipment from Industrial/Commercial/Institutional (ICI) Sources
Prepared by: Kevin Gong
December 11, 2019
139

RULE IDENTIFICATION
Agency Maricopa County Air Quality Department (MCAQD)
SIP Approved Rule 323 – Fuel Burning Equipment from
Rule Industrial/Commercial/Institutional (ICI) Sources
Revised – October 17, 2007
Submitted - January 9, 2008
EPA Approved – October 14, 2009 (74 FR 52693)
Subject of this Rule 323 – Fuel Burning Equipment from
TSD Industrial/Commercial/Institutional (ICI) Sources
Revised – November 2, 2016
Submitted – June 22, 2017
Completeness Complete by operation of law – December 22, 2017
Finding
BACKGROUND
The Maricopa County Air Quality Department (MCAQD) regulates Maricopa County and
the cities of Phoenix, Mesa, Scottsdale, Tempe, Chandler, Glendale, as well as 17 other
jurisdictions and unincorporated County lands. Part of the area regulated by MCAQD is
included in the Phoenix-Mesa area designated as nonattainment for ozone and classified
as Moderate for the 2008 8-hour National Ambient Air Quality Standard (NAAQS) (see 40
CFR 81.303, 81 FR 26699).
Rule 323, “Fuel Burning Equipment from Industrial/Commercial/Institutional (ICI)
Sources,” regulates process heaters, steam units and turbines. The MCAQD identified
one facility that is both a major source of nitrogen oxides (NOx), and has equipment
subject to this rule: the Arizona Public Service’s West Phoenix Power Plant. The non-
electricity generating equipment at West Phoenix Power Plant must therefore implement
RACT for NOx emissions. Another facility with applicable equipment was identified by the
MCAQD, but is not a major source of NOx: New Wincup Holding’s polystyrene cup
manufacturing operations in Phoenix. This equipment is not required to meet RACT
because New Wincup is not a major source of NOx, but we will review the rule’s
applicable requirements for this equipment to ensure that they meet all other CAA
requirements.
Rule 323 was revised as part of the District’s process to ensure that its rules meet the
reasonably available control technology (RACT) requirements of Section 182(b) of the
Clean Air Act (CAA) for ozone nonattainment areas classified as Moderate. Appendix 1 of
the June 22, 2017 submission, Revisions To The State Implementation Plan Revision For
The Maricopa County Air Quality Department Ozone Rules Contained In The Arizona SIP,
titled Analysis Of Reasonably Available Control Technology For The 2008 8-Hour Ozone
140

National Ambient Air Quality Standard (NAAQS) State Implementation Plan (RACT SIP)
(“SIP Analysis”) contains the District’s analysis regarding whether Rule 323 implements
RACT levels of control.
RULE SUMMARY
Rule 323 regulates NOx, sulfur oxide, carbon monoxide, and particulate matter emissions
from steam generating units, cogeneration steam units, indirect-fired process heaters
and turbines not located at power plants. Incinerators, crematories, burn-off ovens, kilns,
direct-fired process heaters, reciprocating internal combustion equipment, equipment
associated with nuclear power plant operations, and water heaters used for the sole
purpose of heating hot water for comfort and for radiant heat are exempt from this rule.
The NOx requirements are contained in section 304 of this rule, and apply to equipment
in different ways based on their heat input rating or combustion type. Subsection 304.1a
requires good combustion practices and tuning, while subsection 304.1b requires
compliance with numeric emission limits. Both requirements apply to gas turbines and all
units rated larger than 100 MMBtu/hr, while all other smaller units may comply with one
or the other.
The rule also describes related recordkeeping, reporting, and monitoring requirements.
Changes from the approved SIP rule include:
1. Removed exemptions for turbines used at military facilities
2. Clarified exemption for all units for low use testing operations that are less
than 36 hours per year.
3. New definition for “Steady State,” and “Ultra Low Sulfur Diesel.”
4. Clarification in section 302 for measurement periods temperature differential
in turbine units for good combustion practices.
5. Clarified language in section 304 for NOx requirements.
6. Strengthened RACT emission limits for NOx. Gaseous fuel fired operations are
limited to 42 ppmv, and liquid fuel-fired operations are limited to 65 ppmv.
7. Carbon monoxide and particulate matter requirements now only allow
compliance determination during steady state operations.
8. Emission control equipment installed to comply with the pollution limits in
this rule are only acceptable if the equipment can demonstrate compliance
with the emission limits. Previously, any emission control system could be
installed to comply with emission standards regardless of its effectiveness.
9. New administrative requirements were added to section 400, which had
previously been reserved. The administrative requirements generally consist
of compliance schedules for units to submit an operations and maintenance
plan, or to modify or install an emissions control system.
10. New recordkeeping and monitoring requirements are in sections 503.3 (for
continuous emission monitoring systems (CEMS) to meet the good
combustion evaluation requirements) and 501 (to require maintaining records
for low use units exempt in section 102).
141

11. New gaseous emissions source testing requirements, including a triennial
source test interval for units rated larger than 100 MMBtu/hr.
12. Additional options for ultra low sulfur diesel fuel verification, and for waste
derived fuel gas sulfur verification.
13. An updated list of approved test methods for this rule.
EVALUATION CRITERIA
The following criteria were used to evaluate the submitted rule.
Enforceability
The Bluebook (Issues Relating to VOC Regulation Cutpoints, Deficiencies, and
Deviations, EPA, May 25, 1988) and the Little Bluebook (Guidance Document
for Correcting Common VOC & Other Rule Deficiencies, EPA Region 9, August
21, 2001) were used to help evaluate compliance with the CAA §110(a)(2)(A)
requirement for enforceability.
Stringency
SIPs must require RACT for each category of sources covered by a Control
Technique Guideline (CTG) document as well as each major source of NOx or
VOC in ozone nonattainment areas classified as Moderate or above (see
sections 182(b)(2) and 182(f)). While there is no CTG for this source category,
the MCAQD has identified major sources of NOx covered by this rule within
the nonattainment area. Accordingly, the RACT requirement applies to these
major sources. The EPA has published an Alternative Control Techniques (ACT)
document titled, “NOx Emissions from Stationary Gas Turbines” (EPA 453/R-
93-007, January 1993) which describes available control techniques and their
estimated costs for gas turbine units. The EPA’s ACT document titled, “NOx
Emissions from Industrial, Commercial & Institutional Boilers” (EPA453/R-94-
022, March 1994) describes similar control techniques and cost guidance for
boiler units. These ACTs and other state and local rules for this category were
used to help evaluate the RACT requirements of CAA §182(b)(2) and §182(f).
SIP Relaxation
CAA §110(l) prohibits EPA from approving any SIP revision that would
interfere with any applicable requirement concerning attainment and
reasonable further progress or any other applicable requirement of the CAA.
In addition, CAA §193 prohibits the modification of any SIP-approved control
requirement in effect before November 15, 1990, in a nonattainment area,
unless the modification insures equivalent or greater emission reductions.
142

EPA EVALUATION
A summary of our evaluation of the three criteria follows.
Enforceability
Rule 323 applies to turbines, steam generating units, and cogeneration units
not used for electricity generation. Incinerators, crematories, burn-off ovens,
kilns, direct-fired process heaters, reciprocating internal combustion
equipment, equipment associated with nuclear power plant operations, and
water heaters used for the sole purpose of heating hot water for comfort and
for radiant heat are exempt.
Units firing on emergency fuel, units testing on emergency fuel, gas turbines
used in fire-fighting, flood control, or in research and development are partially
exempt from the requirements of this rule. The partial exemptions include an
exemption from the NOx limits. We believe that most of these partial
exemptions are reasonable, with the exceptions of the partial exemption for
units fired on emergency fuel and for testing on emergency fuel. Other
jurisdictions with a similar emergency fuel exemption limit the total hours of
emergency fuel firing. Other jurisdictions also require that the County or
District be promptly notified upon switching to emergency fuel. A fuel
emergency should require owners or operators of equipment to take
extraordinary actions if necessary to continue operations, or to shut down until
the emergency passes. Any equipment that is necessary for public safety are
already covered under other exemptions. Therefore, we find that the
exemption for firing on emergency fuel is overly broad, as other similar
regulations for ozone nonattainment areas provide limits for the length of
emergency fuel use.
The exemption for testing on emergency fuel as currently drafted could be
interpreted to allow for exemption from emission limits in any operating
scenario as long as the unit has fired on emergency fuel for testing in a year.
This language should be clarified to indicate that this exemption applies while
this testing is ongoing. Beyond these two aforementioned enforceability issues,
the other applicability criteria are clear and establish which units must comply
with this rule.
Section 200 includes definitions for terms used in this rule. There are several
new definitions and terms in Rule 323 which improve clarity, but there are
other terms used in the rule, such as “boiler” and “continuous emissions
monitoring system” that lack definition. This weakens rule enforceability, and
these terms should be defined in the rule.
Section 300 contains the limits and requirements for controlling emissions
from applicable sources, including PM, sulfur, CO, and NOx. PM control
143

requirements are set out as fuel limits, backhalf analysis for testing, and good
combustion practice requirements for turbines. Sulfur requirements are set
out as a fuel limit. CO limits apply to units rated larger than 100 MMBtu/hour.
The NOx requirements at Section 304 are split into two categories. This section
requires non-turbine units to comply with operational requirements including
burner inspection, regular tuning, and good combustion practices, or with
specified emission limits, or both categories, depending on unit size. Turbines
must comply with both categories regardless of size. We find these
requirements to be sufficiently enforceable.
Section 306 describes requirements for emission control systems that are
installed to reduce pollution. Section 306.1 states that an owner or operator of
an operation which may exceed the other standards in section 300 may comply
by installing an operating an emission control system (ECS) which reduces
emissions to below the applicable standards. However, there is no subsequent
requirement for compliance determination to ensure that the ECS functions to
actually meet the gaseous limits. Our discussion in the “Rule Deficiencies”
section contains additional analysis.
Section 400 contains compliance schedule requirements for units operating an
ECS to submit to the MCAQD an Operations and Maintenance Plan (to be
completed no later than July 2, 2017), submit a schedule for modification to an
ECS if such a modification is necessary to demonstrate full compliance with the
rule (a modified ECS must be installed and achieving compliance no later than
November 2, 2018), and to submit a schedule for the installation of an ECS if
new equipment is necessary (new equipment must be installed and in
compliance no later than November 2, 2019). These dates are reasonable and
support rule enforceability.
Section 500 of the rule contains recordkeeping and reporting requirements for
all equipment subject to this rule, including requirements for units claiming
exemptions. Compliance demonstration requirements are outlined with the
requirements themselves in Section 300 “Standards,” but several applicable
requirements are also in Section 503. These requirements include
requirements for verifying sulfur content in fuel, source test frequency, and
requirements for CEMS. The frequency for gaseous emissions source testing is
set to be done on at least a triennial basis for units with a heat input greater
than 100 MMBtu/hour. Units rated less than this are not required to conduct
source tests according to any frequency. Such units could be located at major
sources of NOx and would lack any compliance determination requirements for
NOx emissions limits. Such NOx emission limits would therefore be
unenforceable for units in this size class. We find this provision deficient.
144

Other recordkeeping and reporting requirements include operating hour and
days of operation for all units, fuel use requirements and fuel switching
records, CEMS records, records demonstrating the maintenance of good
combustion practices, and records for annual capacity factor utilization and
NOx emissions. All records shall be retained for at least 5 years. Other than the
deficiency identified with gaseous emissions source test frequencies, we find
these monitoring, recordkeeping, and reporting requirements are adequate in
supporting rule enforceability.
Stringency
Rule 323 establishes lower NOx emission limits for applicable units, of 42 ppmv
for gas fired units, and 65 ppmv for liquid-fired units, but also allows smaller
non-turbine units (smaller than 100 MMBtu/hr) to comply with certain
operation practices instead of the numeric limits. These good combustion
practices include requiring annual tuning of the unit, burner unit inspection,
air-to fuel ratio calibration, and NOx and CO concentration measurements via
portable analyzer.
The emission limits are consistent with limits for stationary turbines in other
jurisdictions needing to meet RACT, including units of all sizes in the Imperial
County Air Pollution Control District and in the Mojave Desert Air Quality
Management District, and for smaller units in the San Joaquin Valley Air
Pollution Control District, Ventura County Air Pollution Control District, and the
Yolo-Solano Air Quality Management District.
However, these emission limits are not demonstrated to be suitable RACT NOx
limits for boilers, process heaters, and steam generating units. RACT limits for
these units in these other jurisdictions are commonly lower: at 30 ppmv for
gas-fuel fired operation and 40 ppmv for liquid-fuel fired operations. A
requirement consistent with at least these limits for NOx control must be
included in this rule in order to ensure that any such applicable units are
implementing RACT.
Furthermore, non-turbine units smaller than 100 MMBtu/hr may choose to
comply with only the good combustion practice requirements, with are not
demonstrated to be RACT for the units that may be operating at major sources
of NOx. Our analysis below in the “Rule Deficiencies” section provides further
discussion on this issue.
SIP Relaxation
Many of the provisions in this rule are unchanged or more stringent than the
SIP approved rule. Therefore, we find that the rule revisions are consistent
with CAA sections 110(l) and 193.
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RULE DEFICIENCIES
The following deficiencies were identified in a letter dated July 18, 2018, and preclude
full approval of the rule into the SIP1:
1. The emergency fuel use exemptions in Section 104 are overly broad. To correct
this, the MCAQD should clarify in this section that emergency fuel is only
allowed under natural gas curtailments or natural gas emergencies. The
MCAQD should further limit the total allowable length of emergency fuel
burning to be consistent with other jurisdictions (see, Imperial County APCD
Rule 400.1 Section D.3) Also, Rule 323 does not require that the facility
owner/operator notify the MCAQD when switching to emergency fuel, which
Rule 322 “Power Plant Operations” (which regulates similar types of
combustion equipment) does. This is an enforceability issue. Finally, the
language in section 104 exempting units firing emergency for testing purposes
could be interpreted to allow for the exemption during any operating period so
long as the there was a testing period. The MCAQD should clarify that the
exemptions only apply during the testing period.
2. All major sources of NOx must be subject to RACT limits or requirements. All
turbines, and all boilers rated larger than 100 MMBtu/hr must comply with the
limits in section 304.1.b. Boiler units rated between 10 MMBtu/hr and 100
MMBtu/hr may opt to comply with the limits in section 304.1 .b, or tune the
units annually as required in section 304.1a. The burner maintenance
requirements in section 304.1 .a are not RACT, as other jurisdictions regulating
units in this size category are able to achieve numeric limits (down to 5
MMBtu/hr in Imperial County APCD Rule 400.2) or have more stringent tuning
requirements (as seen in Ventura County APCD Rule 74.15.1 and South Coast
AQMD Rule 1146, Attachment A). As the rule is written, major source units in
the nonattainment area are only required to tune the engine instead of
complying with a RACT NOx limit. MCAQD must clarify that larger units (e.g.
annual heat input rating of 50 MMBtu/hr or greater, and annual heat input of
220,000 therms or greater) shall comply with Rule 323 by meeting a NOx limit
(as seen in San Diego County APCD Rule 69.2).
3. The NOx limits of 42 ppmv for gas fuel-fired operations and 65 ppmv for liquid
fuel-fired operations for non-turbine combustion equipment in this rule are
not consistent with other jurisdictions limits and are not RACT. Limits in other
ozone nonattainment jurisdictions, such as Imperial County APCD Rule 400.2
and Sacramento Metropolitan AQMD, are set at are at 30 ppmv and 40 ppmv
for gas and liquid fuel-fired operations.
1 Letter from Doris Lo, U.S. EPA Region 9 to Philip A. McNeely, Maricopa County Air Quality
Department, “Re: EPA Comments on the Maricopa County Air Quality Department Rules 323 and 324”
dated July 18, 2018.
146

4. Section 306 states that operators may comply with the limits in this rule by
installing an ECS, and notes that such systems must be properly operated and
maintained in accordance with an approved operations and maintenance plan.
The rule language in section 306 could be interpreted to mean that the
installation of an ECS on its own would allow compliance with the emission
limits. However, an ECS that does not sufficiently reduce emissions could meet
section 306’s requirement without any verification for meeting the other
section 300 requirements. The effectiveness of such a system in meeting the
applicable emission standards is unknown without a compliance determination
requirement (which in section 503 only applies to sections 301-304, and only
for units larger than 100 million Btu/hr). MCAQD must include language that
states that an ECS or combustion control system must also be source tested to
confirm compliance with the limit or create parametric monitoring
requirements to put in the operation and maintenance plan. Alternatively, the
rule language in section 306 should be clarified to not allow for the installation
of an ECS to be an alternative to compliance with the RACT limits in sections
301-304.
5. The operations and maintenance plan requirements are only approved by the
Control Officer in section 306.3. This constitutes unacceptable director’s
discretion. In addition, the rule allows the facility operator to change the
operation and maintenance plan in section 306.3.d by submitting changes.
MCAQD must revise this language to resolve these enforceability questions,
either by removing this discretion, including the EPA in approval of these plans,
or outlining clear criteria that must be met for approval. The operation and
maintenance plan must include the control equipment manufacturer’s
operation and maintenance guidelines. If the MCAQD chooses to revise section
306 so that installation of an emission control system does not result in
automatic compliance with the emission limits in sections 301-304, then this
discretion may be acceptable as a source test would be the primary
determinant of compliance with RACT requirements.
6. Section 503.2 specifies that boilers larger than 100 MMBtu/hr must source test
triennially, but does not describe a testing frequency for other units. Other
units must be tested at least triennially. MCAQD must also cite the appropriate
test method from the list in section 500.
7. Section 200 of this rule and Maricopa’s Rule 100 General Provisions and
Definitions does not include a definition for “boiler,” which is used throughout
this rule, and in the context of definitions for “annual capacity factor,” “steam
generating unit,” and others. For purposes of enforceability, such a definition is
necessary.
8. Section 200 also does not include a definition for “continuous emissions
monitoring system.” For purposes of enforceability, such a definition is
necessary.
147

ADDITIONAL RECOMMENDATIONS FOR THE NEXT RULE REVISION
The following revisions were also identified in the July 18, 2018 letter. They are not
currently the basis for rule disapproval, but are recommended for the next time the rule
is amended.
Section 219 defines “steady state” — This is defined as a “safe stable megawatt load”,
which is the incorrect measure for non-EGU sources like general ICI sources which may
not output power in megawatts.
COMMITMENT LETTER CONDITIONS
On January 28, 2019, the MCAQD transmitted a letter in response to the EPA’s rule
approvability comments made in the course of our evaluation. On February 25, 2019, the
ADEQ transmitted the MCAQD letter and committed to submit to EPA rule revisions that
will address identified deficiencies. The letters commit to resolve outstanding
approvability issues with specific enforceable provisions. The following commitments (in
addition to resolving any other approvability issues identified in this TSD) must be met in
order for revisions to Rule 323 to be fully approved into the SIP, and to fully meet the
RACT SIP requirement for this source category.
1. The MCAQD commits to clarify that the exemptions for emergency fuel use
only apply during natural gas curtailments and natural gas emergencies and for
up to 36 cumulative hours per year for testing, reliability, training, and
maintenance purposes. The MCAQD will add a requirement for the owner or
operator to notify the MCAQD when switching to emergency fuel. The MCAQD
will also limit the total allowable length of emergency fuel combustion during
natural gas curtailments and natural gas emergencies to 168 hours per year
per combustion unit (for combustion units located at a major stationary source
of nitrogen oxides).
2. The MCAQD commits to implementing current RACT emission limits and RACT
tuning procedures for fuel burning equipment located at a major stationary
source of NOx. Compliance with the RACT emission limits will be required for:
• Stationary gas turbines (rated > 10 MMBtu/hour)
• Boilers, steam generating units, and cogeneration steam generating units
(rated > 100 MMBtu/hr)
• Boilers, steam generating units, and cogeneration steam generating units
(rated > 50 MMBtu/hr with usage exceeding 10% of annual capacity) that
are located at a major stationary source of NOx.
Compliance with RACT tuning procedures will be required for:
• Boilers, steam generating units, and cogeneration steam generating units
(rated > 10 MMBtu/hr and ≤ 50 MMBtu/hr with annual heat input >
148

220,000 therms) that are located at a major stationary source of NOx.
3. The MCAQD commits to clarify that installation of an ECS or a combustion
control system is not an alternative to complying with applicable numeric
emission limits. The MCAQD will also clarify that the owner or operator of a
combustion unit that is subject to a numeric NOx emission limit must
demonstrate compliance by conducting a performance test. The MCAQD will
also revise the O&M plan requirements to clarify that the O&M plan must
include operating parameters that will be monitored to ensure continued
operation of the ECS in the manner the ECS was operated during the
performance test.
4. The MCAQD commits to clarify that any owner or operator using an ECS to
comply with numeric emission limits must establish parametric monitoring
parameters during the required performance test. The MCAQD will clarify that
these parametric monitoring parameters shall be included in the O&M plan in
order for the Control Officer to approve the O&M plan. The MCAQD will also
clarify that the ECS should be operated and maintained according to the
manufacturer's specifications (or in accordance with good engineering
practices if the manufacturer does not provide maintenance specifications).
5. The MCAQD commits to clarify that all combustion units that are subject to a
numeric emission limit must be performance tested to demonstrate
compliance with the applicable emission limits. The MCAQD commits to clarify
that performance tests must be conducted in accordance with the test
methods specified in Section 504 or in accordance with other EPA approved
test methods. The MCAQD also commits to requiring performance tests at
least once every 5 years for combustion units rated less than 100 million BTU
per hour.
6. The MCAQD commits to define the word “boiler” in Rule 323.
7. The MCAQD commits to define “continuous emissions monitoring system” in
Rule 323.
EPA ACTION
Overall, we believe that the revisions are on balance SIP-strengthening. However, the
issues described above in the “Rule Deficiencies” section preclude the full approval of
this rule into the Arizona SIP. The County and State’s commitment to address these
deficiencies and submit a revised rule within one year of our final action of this submittal
allows the EPA to conditionally approve the submitted version of Rule 323 into the
Arizona SIP. Therefore, we recommend conditionally approving Rule 323 into the SIP.
If the EPA approves a revised Rule 323 addressing the deficiencies above, we would be
able to certify that Maricopa County is implementing RACT for sources subject to this
rule.
149

REFERENCES
1. “Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations,”
(a.k.a., Bluebook) EPA OAQPS, May 25, 1988.
2. “Guidance Document for Correcting Common VOC & Other Rule Deficiencies,”
(a.k.a., Little Bluebook), EPA Region 9, August 21, 2001.
3. “NOx Emissions from Stationary Gas Turbines,” EPA 453/R-93-007, January 1993.
4. “NOx Emissions from Industrial, Commercial & Institutional Boilers,” EPA453/R-
94-022, March 1994.
5. “De Minimis Values for NOx RACT,” Memorandum from G. T. Helms, Group
Leader, Ozone Policy and Strategies Group, U.S. EPA, January 1, 1995.
6. “Cost-Effective Nitrogen Oxides (NOx) Reasonably Available Control Technology
(RACT),” Memorandum from D. Ken Berry, Acting Director, Air Quality
Management Division, US. EPA, March 16, 1994.
7. “Supplemental Table 1. Major Sources of NOx and VOC in Maricopa County,”
attachment to e-mail titled “Maricopa County RACT SIP: EPA Conference Call,”
from Johanna Kuspert, Maricopa County Air Quality Department, dated January 3,
2019.
8. Imperial County Air Pollution Control District Rule 400.1, “Stationary Gas
Turbine(s) – Reasonably Available Control Technology (RACT)”, as amended
February 23, 2010 and submitted to EPA on July 20, 2010.
9. Imperial County Air Pollution Control District Rule 400.2, “Boilers, Process Heaters
and Steam Generators”, as amended February 23, 2010 and submitted to the EPA
on July 20, 2010.
10. Mojave Desert Air Quality Management District Rule 1159, “Stationary Gas
Turbines”, as amended September 28, 2009 and submitted to the EPA on May 17,
2010.
11. Mojave Desert Air Quality Management District Rule 1157, “Boilers & Process
Heaters”, as amended May 19, 1997 and submitted to the EPA on August 1, 1997.
12. San Joaquin Valley Air Pollution Control District Rule 4306, “Boilers, Steam
Generators, and Process Heaters – Phase 3,” amended on October 16, 2008 and
submitted to the EPA on March 17, 2009.
13. San Joaquin Valley Air Pollution Control District Rule 4703, “Stationary Gas
Turbines,” amended on September 20, 2007 and submitted to the EPA on March
7, 2008.
14. Ventura County Air Pollution Control District Rule 74.15.1, “Boilers, Steam
Generators, and Process Heaters,” amended on June 23, 2015 and submitted to
the EPA on November 13, 2015.
15. Ventura County Air Pollution Control District Rule 74.23, “Stationary Gas
Turbines,” amended on January 8, 2002 and submitted to the EPA on March 15,
2002.
150

16. Yolo-Solano Air Quality Management District Rule 2.27, “Industrial, Institutional,
and Commercial Boilers, Steam Generators, and Process Heaters,” amended
August 14, 1996 and submitted to the EPA on October 18, 1996.
17. Yolo-Solano Air Quality Management District Rule 2.34, “Stationary Gas
Turbines,” amended November 12, 2014 and submitted to the EPA on June 26,
2015.
151

Return to list of attachments
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION IX AIR DIVISION
Technical Support Document
for
EPA’s Rulemaking
for the
Arizona State Implementation Plan
Maricopa County Air Quality Department
Rule 324
Stationary Reciprocating Internal Combustion Engines (RICE)
Prepared by: Kevin Gong
December 11, 2019
152

RULE IDENTIFICATION
Agency Maricopa County Air Quality Department (MCAQD)
SIP Approved Rule 324 – Stationary Internal Combustion (IC) Engines
Rule Revised – October 17, 2007
Submitted - January 9, 2008
EPA Approved – October 14, 2009 (74 FR 52693)
Subject of this Rule 324 – Stationary Reciprocating Internal Combustion
TSD Engines (RICE)
Revised – November 2, 2016
Submitted – June 22, 2017
Completeness Complete by operation of law – December 22, 2017
Finding
BACKGROUND
The Maricopa County Air Quality Department (MCAQD) regulates Maricopa County and
the cities of Phoenix, Mesa, Scottsdale, Tempe, Chandler, Glendale, as well as 17 other
jurisdictions and unincorporated County lands. Part of the area regulated by MCAQD is
included in the Phoenix-Mesa area designated as nonattainment for ozone and classified
as Moderate for the 2008 8-hour National Ambient Air Quality Standard (NAAQS) (see 40
CFR 81.303, 81 FR 26699).
Rule 324, “Stationary Reciprocating Internal Combustion Engines (RICE),” regulates
internal combustion engines which are sources of oxides of nitrogen (NOx) emissions.
The MCAQD identified four facilities that are both major sources of NOx, and have
equipment subject to this rule.
Rule 324 was revised as part of the District’s process to ensure that its rules meet the
reasonably available control technology (RACT) requirements of Section 182(b) of the
Clean Air Act (CAA) for ozone nonattainment areas classified as Moderate. Appendix 1 of
the June 22, 2017 submission, Revisions To The State Implementation Plan Revision For
The Maricopa County Air Quality Department Ozone Rules Contained In The Arizona SIP,
titled Analysis Of Reasonably Available Control Technology For The 2008 8-Hour Ozone
National Ambient Air Quality Standard (NAAQS) State Implementation Plan (RACT SIP)
(“SIP Analysis”) contains the District’s analysis regarding whether Rule 324 implements
RACT levels of control.
RULE SUMMARY
Rule 324 regulates NOx, volatile organic compound (VOC), sulfur oxide, carbon
monoxide, and particulate matter emissions from stationary reciprocating internal
combustion engines (RICE). This rule includes emission limits for spark ignition and
153

compression ignition engines rated greater than 250 brake horsepower (bhp), as well as
any combination of engines rated greater than 50 bhp if they aggregate to greater than
250 bhp. Rotary engines (including turbines), non-emergency engines operated for
performance verification, compressed gas engines used for solar testing and research,
engines operated at nuclear power plants for safety reasons, engines used for evaluating
engine performance, engines operated 100 hours or less in a calendar year for training
purposes, and engines defined are nonroad engines are entirely exempt from this rule.
Emergency engines, low-use operations for non-emergency engines, and engines subject
to 40 CFR part 63, subpart ZZZZ1 are partially exempt from this rule.
The rule also contains related recordkeeping, reporting, and monitoring requirements.
Changes from the approved SIP rule include:
1. Clarified applicability to units that are also subject to federal internal
combustion engine standards. Engines subject to 40 CFR Part 60 IIII2 and JJJJ3,
or 40 CFR Part 63 ZZZZ IC engines operated as non-road engines are exempt or
partially exempt from this rule.
2. Definitions were revised, with the definition for “Existing Engine” deleted.
3. Added new restrictions on the sulfur content of fuels, which are met through
allowing only ultralow sulfur fuels for combustion.
4. Reorganized the tables of NOx limits for compression and spark ignition
engines. New requirements for new engines to comply with applicable federal
standards.
5. Added requirements for modified engines to comply with updated limits, and
requirements for all engines to install non-resettable totalizing meters.
6. Updated compliance schedules for units that are being removed from service
to comply with rule requirements, and for units to install non-resetting
totalizing hour meters.
7. Added new compliance determination options for engines that are certified to
meet federal requirements in 40 CFR 89, 90, or 1039, and for engines in the
same engine family. Engines must be tested at the request of the Control
Officer.
8. Additional options for ultralow sulfur diesel fuel verification, and for waste
derived fuel gas sulfur verification.
9. An updated list of approved test methods for this rule.
1 National Emissions Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal
Combustion Engines.
2 Standards of Performance for Stationary Compression Ignition Internal Combustion Engines.
3 Standards of Performance for Stationary Spark Ignition Internal Combustion Engines.
154

EVALUATION CRITERIA
The following criteria were used to evaluate the submitted rule.
Enforceability
The Bluebook (Issues Relating to VOC Regulation Cutpoints, Deficiencies, and
Deviations, EPA, May 25, 1988) and the Little Bluebook (Guidance Document
for Correcting Common VOC & Other Rule Deficiencies, EPA Region 9, August
21, 2001) were used to help evaluate compliance with the CAA §110(a)(2)(A)
requirement for enforceability.
Stringency
SIPs must require RACT for each category of sources covered by a Control
Technique Guideline (CTG) document as well as each major source of NOx or
VOC in ozone nonattainment areas classified as Moderate or above (see
sections 182(b)(2) and 182(f)). While there is no CTG for this source category,
the MCAQD has identified major sources of NOx covered by this rule within
the nonattainment area. Accordingly, the RACT requirement applies to these
major sources. The EPA has published an Alternative Control Techniques (ACT)
document titled, “NOx Emissions from Stationary Reciprocating Internal
Combustion Engines” (EPA 453/R-93-032, July 1993) which describes available
control techniques and their estimated costs for internal combustion engines.
This ACT and other state and local rules for this category were used to help
evaluate Rule 324 against the RACT requirements of CAA §182(b)(2) and
§182(f).
SIP Relaxation
CAA §110(l) prohibits EPA from approving any SIP revision that would
interfere with any applicable requirement concerning attainment and
reasonable further progress (RFP) or any other applicable requirement of the
CAA. In addition, CAA §193 prohibits the modification of any SIP-approved
control requirement in effect before November 15, 1990, in a nonattainment
area, unless the modification insures equivalent or greater emission
reductions.
EPA EVALUATION
A summary of our evaluation of the three criteria follows.
Enforceability
Rule 324 applies to stationary reciprocating internal combustion engines (RICE)
rated greater than 250 bhp, or a combination of stationary RICE rated greater
than 50 bhp used at a source whose aggregated rated bhp is greater than 250
bhp. Engines used for engine research, operated for performance testing,
compressed gas engines used for solar testing and research, engines operated
as emergency engines at a nuclear power plant, or engines used for training
155

purposes for less than 100 hours per calendar year are exempt from this rule.
Engines that are operated as nonroad engines are also exempt.
Engines used for backup power, used for emergency pumping, used for lighting
airport runways, used for sewage overflow mitigation or prevention, and
engines used as non-emergency engine replacement only during engine repairs
are partially exempt. We believe that these exemptions describe reasonable
emergency circumstances, with the following exceptions: (1) Emergency
engines operated for airport runway lighting or sewage overflow prevention
could theoretically supplant regular power or an otherwise compliant engine if
such operations occurred regularly. (2) On-site emergency engines replacing
non-emergency engines during repair should need to either meet the rule’s
emission limits or be time-limited in their operation as a replacement. While
the definition of “emergency engine” does include a provision stating that
operations shall not exceed 500 hours in a calendar year, it is unclear based on
the current language if that applies to all emergency engines or just a subset of
emergency engine operations.
Section 200 includes definitions for terms used in this rule. The definitions for
“existing engine” and “new engine” were deleted. The definition for “identical
replacement engine” was clarified and strengthened. Previously, such engines
that had equal or lower emissions, or met emission control technology
requirements were allowed. Now such engines must have equal or lower
emissions and also meet control technology requirements. Other definitions
were revised or renamed, but are substantially the same. The term “prime
engine” was replaced with the term “non-emergency engine,” and the term
“internal combustion (IC) engine, stationary” was replaced with the term
“stationary internal combustion engine.”
Section 300 contains the limits and requirements for controlling emissions
from applicable engines. Good combustion practice requirements and tuning
procedures are set out in section 302. Alternative tuning procedures are no
longer allowed, and handheld monitors may be used by the Control Officer to
determine compliance. This revision can improve enforceability, presuming
that the technician using the portable analyzer is trained in its use.
Recordkeeping requirements in section 500 help to ensure that these tuning
and combustion practice requirements are enforceable.
The emission limits for existing engines are contained in Table 1 for
compression-ignition engines manufactured or modified prior to July 11, 2005,
and Table 2 for spark-ignition engines manufactured or modified prior to June
12, 2006. Any units manufactured or modified since then are required to
comply with federal standards of performance as set forth in 40 CFR part 60
subparts IIII and JJJJ. These federal requirements for newer engines are also
156

not codified into this rule or any other SIP-approved provision, which are
necessary to demonstrate the implementation of RACT for major sources of
NOx under CAA section 182(f), and constitutes an approvability issue.
Compliance determination for the emission limits set forth in this rule are only
required at the request of the Control Officer. This constitutes unacceptable
Control Officer discretion.
Section 306 allows for engines defined as “equivalent replacement engines” or
“identical replacement engines” to be treated as the original engine that was
replaced. This provision would be unenforceable as emission reductions from
equivalent replacement engines cannot be quantified under this rule’s current
requirements. The definition for “equivalent replacement engine” allows for
replacement engines that could have a bhp rating up to 20% higher than the
engine being replaced so long as the replacement resulted in an emission
decrease. Because compliance determination is only required at the request of
the Control Officer, emission reductions would be unaccountable, and the
requirements would be unenforceable.
Section 400 contains compliance schedule requirements for engines being
removed from service in order to comply with the rule, or for engines requiring
the installation of a non-resetting totalizing hour meter. These provisions are
sufficient to ensure compliance with the associated requirements, but as we
note above, there is no compliance determination schedule for any other
requirements in this rule.
Section 500 of the rule contains recordkeeping and reporting requirements for
all engines subject to this rule, including requirements for units claiming
exemptions. As we note above, each of the compliance determination
requirements for emission limits is only required upon request of the Control
Officer, without any recurring frequency for tests in engines that are not
otherwise certified to meet emission limits (e.g., for units complying with 40
CFR Part 60 Subparts IIII or JJJJ). We find this provision deficient.
Other recordkeeping and reporting requirements include operating hours and
days of operation for all units, fuel use requirements, records demonstrating
the maintenance of good combustion practices, and hourly operations records
for units operating under the low use exemption. All records shall be retained
for at least 5 years. We find these monitoring, recordkeeping, and reporting
requirements are adequate in supporting rule enforceability.
Stringency
Rule 324 establishes pollution emission limits for engines rated greater than
250 bhp, and for any group of engines rated larger than 50 bhp if their sum
output is 250 bhp or greater. It is unclear from the rule text what requirements
157

a group of summed 50 bhp must comply with, as the rule’s emission
requirements are only applicable to units greater than 250 bhp. In addition,
other air district rules, including Imperial County APCD Rule 400.3 and Ventura
County APCD Rule 74.9, are generally applicable to all units down to the 50 bhp
threshold.
The rule’s limits NOx, VOC, and CO emissions from compression-ignition
engines and spark-ignition engines, are laid out in Tables 1 and 2. However,
compression-ignition engines manufactured or modified after July 11, 2005,
and spark-ignition engines manufactured or modified after June 12, 2006, must
comply with the applicable New Source Performance Standards in 40 CFR part
60. The MCAQD must demonstrate that these federal requirements are
appropriate as RACT, as RACT may constitute emission limits, control
technology, or operational requirements that are more stringent than the
federal standards, which apply nationally, including in areas determined to be
in attainment.
SIP Relaxation
Many of the provisions in this rule are unchanged or more stringent than the
SIP approved rule. Therefore, we find that the rule revisions are consistent
with CAA sections 110(l) and 193.
RULE DEFICIENCIES
The following deficiencies were identified in a letter dated July 18, 2018, and preclude
full approval of the rule into the SIP:4
1. The submitted rule’s current structure of applicability and emission limits does
not clearly outline a RACT limit for NOx and VOC emissions from all applicable IC
engines. The MCAQD should review similar source category regulations in other
jurisdictions (San Diego APCD Rule 69.4 and Yolo-Solano AQMD Rule 2.32) on how
they structure clearer RACT limits that may include similar or more stringent
requirements or limits for engines otherwise subject to federal requirements and
standards in 40 CFR part 60, subparts IIII and JJJJ. We understand that units may
need to comply with more stringent Federal standards in some cases, but a RACT
limit would not interfere with a facility’s compliance with a more stringent limit.
The Clean Air Act requires that RACT limitations be approved into the Federally-
enforceable SIP. It is inappropriate to rely on requirements outside of the SIP,
such as NSPS standards found in 40 CFR Part 60.
4 Letter from Doris Lo, U.S. EPA Region 9 to Philip A. McNeely, Maricopa County Air Quality
Department, “Re: EPA Comments on the Maricopa County Air Quality Department Rules 323 and 324”
dated July 18, 2018.
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2. The submitted rule only applies to engines rated greater than 250 bhp, and to
engines greater than 50 bhp when operating at a facility whose units sum to
greater than 250 bhp. The MCAQD should lower the applicability threshold to 50
bhp to be in line with other jurisdictions’ RACT rules. The current rule also does
not clearly state compliance requirements for 50 bhp engines summed at a 250
bhp facility.
The following deficiencies were identified in a letter dated July 1, 2019, and also preclude
full approval of the rule into the SIP:5
3. The submitted rule allows for flexibility in the treatment of replacement engines.
In section 104.6, emergency engines that serve as backup to replace non-
emergency engines may do so until the non-emergency engine is repaired, but
this time span is otherwise unbounded, and may operate above RACT limits. The
MCAQD should restrict the amount of time allowed to operate that emergency
engine, or the backup engine should be required to meet RACT limits. Current
rule provisions in sections 207 and 306 also allow for engines that are deemed
equivalent or identical to replace existing engines to be treated the same as the
engine being replaced, but there are no requirements for replacement engines to
quantify emissions equivalency or reductions.
4. The submitted rule does not specify a compliance determination interval for
engines, beyond at the Control Officer’s discretion. This provision is found in
section 501.1b.
ADDITIONAL RECOMMENDATIONS FOR THE NEXT RULE REVISION
The following revisions were also identified in the July 18, 2018 letter. They are not
currently the basis for rule disapproval, but are recommended for the next time the rule
is amended.
1. Section 103.1(e) exempts stationary engines at a nuclear power plant used for
safety reasons. Please describe the engines used at these facilities and explain
why such plants cannot use compliant engines for safety applications.
2. Section 104 and section 205 provide special considerations for emergency
engines. Please explain why these engines need special consideration, when
these engines already exist on site. Please characterize the number of sources
that have non-compliant engines and would qualify under these partial
exemptions.
5 Letter from Doris Lo, U.S. EPA Region 9 to Philip A. McNeely, Maricopa County Air Quality Department,
“Re: Additional EPA Comments on Maricopa County Air Quality Department Rule 324” dated July 1, 2019.
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3. Section 105 describes a low use threshold that varies between 100-200 hours per
year depending on whether the engine is above or below a 1000 bhp threshold.
How many engines are in each size class, and why is this threshold a reasonable
cut-point?
4. Section 103.1.g exempts stationary engines used for training purposes. The term
“training” is undefined. Please define what activities constitute valid training with
respect to engines in this context.
COMMITMENT LETTER CONDITIONS
On January 28, 2019, the MCAQD transmitted a letter in response to the EPA’s rule
approvability comments made in the course of our evaluation. On February 25, 2019, the
ADEQ transmitted the MCAQD letter and committed to submit to the EPA rule revisions
that will address identified deficiencies. The letter committed to resolve the following
outstanding approvability issues with specific enforceable provisions.
1. The MCAQD commits to restructure the rule to clarify applicability and emission
limits. The MCAQD will retain existing SIP requirements for stationary RICE that
are not located at a major stationary source of nitrogen oxides. The MCAQD will
retain the existing numeric emission limits in SIP Rule 324 for non-emergency
engines that are located at a major stationary source of nitrogen oxides (because
these limits are consistent with RACT limits in other jurisdictions).
2. The MCAQD commits to lower the applicability threshold to 50 bhp for stationary
RICE located at a major source of nitrogen oxides. The MCAQD will also clarify
what emission limits apply to non-emergency engines rated above 50 bhp that
are located at a major stationary source of nitrogen oxides.
We received an additional commitment letter from the MCAQD on December 5, 2019, to
address the deficiencies identified in our July 1, 2019 comment letter. The following
commitments must be met in order for revisions to Rule 324 to be fully approved into
the SIP, and to meet the RACT SIP requirement for the source category.
3. The MCAQD commits to clarify constraints on the amount of time an emergency
engine can be used to replace a non-emergency engine, and to clarify the
definition for “emergency engine”.
4. The MCAQD commits to remove the provisions allowing for equivalent engines to
be treated as the original engine without proper source testing or emissions
verification procedures.
5. The MCAQD commits to include compliance determination intervals for non-
emergency engines located at both major sources and for those not located at
major sources.
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All of the commitments listed above must be met in order for revisions to Rule 324 to be
fully approved into the SIP, and to meet the RACT SIP requirement for these sources at
major sources of NOx in Maricopa County.
EPA ACTION
The issues described above in the “Rule Deficiencies” section preclude the full approval
of this rule into the Arizona SIP. The MCAQD and ADEQ’s commitment to address these
deficiencies and submit a revised rule within one year of our final action of this submittal
would allow the EPA to conditionally approve the submitted version of Rule 324 into the
Arizona SIP.
If the EPA approves a revised Rule 324 addressing the deficiencies above, we would be
able to certify that the MCAQD is implementing RACT for sources subject to this rule.
REFERENCES
1. “Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations,”
(a.k.a., Bluebook) EPA OAQPS, May 25, 1988.
2. “Guidance Document for Correcting Common VOC & Other Rule Deficiencies,”
(a.k.a., Little Bluebook), EPA Region 9, August 21, 2001.
3. NOx Emissions from Stationary Reciprocating Internal Combustion Engines,” EPA
453/R-93-032, July 1993.
4. “De Minimis Values for NOx RACT,” Memorandum from G. T. Helms, Group
Leader, Ozone Policy and Strategies Group, U.S. EPA, January 1, 1995.
5. “Cost-Effective Nitrogen Oxides (NOx) Reasonably Available Control Technology
(RACT),” Memorandum from D. Ken Berry, Acting Director, Air Quality
Management Division, US. EPA, March 16, 1994.
6. “Supplemental Table 1. Major Sources of NOx and VOC in Maricopa County,”
attachment to e-mail titled “Maricopa County RACT SIP: EPA Conference Call,”
from Johanna Kuspert, Maricopa County Air Quality Department, dated January 3,
2019.
7. Imperial County Air Pollution Control District Rule 400.3, “Internal Combustion
Engine(s),” as adopted on November 22, 2013 and submitted to EPA on February
10, 2014.
8. San Diego County Air Pollution Control District Rule 69.4, “Stationary
Reciprocating Internal Combustion Engines,” amended on July 30, 2003 and
submitted to the EPA on November 4, 2003.
9. Ventura County Air Pollution Control District Rule 74.9, “Stationary Internal
Combustion Engines,” amended on November 8, 2055 and submitted to the EPA
on March 10, 2006.
10. Yolo-Solano Air Quality Management District Rule 2.32, “Stationary Internal
Combustion Engines,” amended on October 10, 2001 and submitted to the EPA
on November 28, 2001.
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