AQ-2024-004-RULE205-REPORTTOBOARDOFSUPERVISORS.PDF

Maricopa County — Formal (2025-05-21)

View PDF Item 12 Meeting page

Extracted text (via pymupdf) 271875 characters
Air Quality Department 
301 W. Jefferson St., Suite 410  
Phoenix, Arizona 85003 
 
P: 602-506-6010 
E: AQMail@maricopa.gov 
 
 
 
 
 
 
 
 
 
 
 
 
 
Enhanced Regulatory Outreach Program 
Maricopa County Air Quality Department 
Notice of Public Hearing 
Subject: 
Rule 205 (Emission Offsets Generated by 
Voluntary Mobile Source Emission 
Reduction Credits) 
Date/Time:  
May 21, 2025, at 9:30 a.m. 
Location:  
Board of Supervisors’ Auditorium 
205 W. Jefferson St., Phoenix, Arizona 85003 
The Maricopa County Board of Supervisors is scheduled to conduct a public hearing to solicit 
comments on the proposed revisions to Maricopa County Air Pollution Control Regulations, 
Rule 205 (Emission Offsets Generated by Voluntary Mobile Source Emission Reduction 
Credits), the submission of the amended rule as a revision to the Arizona state 
implementation plan (SIP), and the approval of the withdrawal of the original May 4, 2023, 
Rule 205 SIP submittal. 
 
You may comment on the proposed rule using the Enhanced Regulatory Outreach Program 
(EROP)  online comment form. 
 
AQ-2024-004-Rule 205 (Emission Offsets Generated by Voluntary Mobile Source Emission 
Reduction Credits) 
 
The purpose of Rule 205 is to allow for the generation and certification of mobile source 
emission reduction credits (MERCs) for use as emission offsets through voluntary captive 
fleet vehicle replacement or retrofit. The purpose of the rulemaking is to remedy deficiencies

Air Quality Department 
301 W. Jefferson St., Suite 410  
Phoenix, Arizona 85003 
 
P: 602-506-6010 
E: AQMail@maricopa.gov 
identified by the U.S. Environmental Protection Agency (EPA) and to address stakeholder 
comments.  
 
On May 4, 2023, MCAQD submitted Rule 205 to the EPA for approval into the Arizona SIP. EPA 
reviewed Rule 205 and identified deficiencies which precluded approval of Rule 205 into the 
SIP. MCAQD has worked with the EPA to adequately address the deficiencies. 
 
Additionally, MCAQD received stakeholder feedback proposing an additional rule revision 
under Appendix A whereby baseline emissions are determined using the original vehicle 
engine model year. This revision is not part of the revisions to address the EPA identified 
deficiencies. This proposed revision will allow a greater amount of MERCs to be calculated 
thereby creating a greater incentive for captive fleet owners to replace or retrofit old, higher 
NOx emitting vehicles. Rule 205 was developed as an economic incentive program and the 
only way to make it an effective incentive program is by revising the MERC calculation to use 
the emissions of the original vehicle. 
 
Members of the public may attend the Board meeting in person or view the meeting online. 
Please check the Board of Supervisors’ website at least 24 hours before the date of the 
public hearing for instructions for remote access. Live video feeds are also available 
at www.maricopa.gov.  
 
For more information regarding this rulemaking, please refer to the Report to the Board of 
Supervisors attached to this notice and available on the EROP Active Regulatory Process 
webpage. A copy of the SIP submittal and Economic Incentive Program supporting document 
will be available at least 30 days prior to the hearing for public inspection at the offices of the 
Maricopa County Air Quality Department, 301 West Jefferson Street, Suite 410, Phoenix, 
Arizona 85003. The SIP submittal and Economic Incentive Program supporting document will 
also be available on the EROP Active Regulatory Process webpage at least 30 days prior to 
the hearing. In addition, copies of the Report to the Board of Supervisors, SIP submittal, and 
Economic Incentive Program supporting document can be obtained by calling 602-506-6010. 
 
MCAQD will take reasonable measures to provide access to department services to 
individuals with limited ability to speak, write, or understand English and/or to those with

Air Quality Department 
301 W. Jefferson St., Suite 410  
Phoenix, Arizona 85003 
 
P: 602-506-6010 
E: AQMail@maricopa.gov 
disabilities. Requests for language interpretation services or for disability accommodations 
must be made at least 48 hours in advance by contacting: 602-506-6443. 
 
MCAQD tomará las medidas necesarias para brindar acceso a los servicios del 
departamento a personas que no dominan el idioma inglés y/o personas con 
discapacidades. Las solicitudes de servicios de interpretación de otro idioma o 
adaptaciones para discapacitados deben realizarse con al menos 48 horas de anticipación 
comunicándose con: 602-506-6443.

Air Quality Department 
301 W. Jefferson St., Suite 410  
Phoenix, Arizona 85003 
 
P: 602-506-6010 
E: AQMail@maricopa.gov 
 
 
 
 
 
 
 
 
 
 
 
 
 
Executive Summary of the Report to the Board of Supervisors 
Prepared by Maricopa County Air Quality Department 
 
Board Hearing Date: 
May 21, 2025 
 
Case Number/Title:  
AQ-2024-004-Rule 205 (Emission Offsets Generated by Voluntary 
Mobile Source Emission Reduction Credits) 
 
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: 
 
The purpose of Rule 205 is to allow for the generation and certification of mobile source 
emission reduction credits (MERCs) for use as emission offsets through voluntary captive 
fleet vehicle replacement or retrofit. The purpose of the rulemaking is to remedy deficiencies 
identified by the U.S. Environmental Protection Agency (EPA) and to address stakeholder 
comments.  
 
On May 4, 2023, MCAQD submitted Rule 205 to the EPA for approval into the Arizona SIP. EPA 
reviewed Rule 205 and identified deficiencies which precluded approval of Rule 205 into the 
SIP. MCAQD has worked with the EPA to adequately address the deficiencies. 
 
Additionally, MCAQD received stakeholder feedback proposing an additional rule revision 
under Appendix A whereby baseline emissions are determined using the original vehicle 
engine model year. This revision is not part of the revisions to address the EPA identified 
deficiencies. This proposed revision will allow a greater amount of MERCs to be calculated

Air Quality Department 
301 W. Jefferson St., Suite 410  
Phoenix, Arizona 85003 
 
P: 602-506-6010 
E: AQMail@maricopa.gov 
 
 
 
 
 
 
 
 
 
 
 
thereby creating a greater incentive for captive fleet owners to replace or retrofit old, higher 
NOx emitting vehicles. Rule 205 was developed as an economic incentive program and the 
only way to make it an effective incentive program is by revising the MERC calculation to use 
the emissions of the original vehicle. 
 
Overview of Stakeholder Input and Staff Responses: 
 
During the rulemaking process, MCAQD received written feedback from two stakeholders 
who expressed neither support nor opposition to the rulemaking. MCAQD representatives 
met with each stakeholder and worked with them to address their comments. 
A summary of the comments and the MCAQD responses to the comments are included 
under Section 9 of the attached Draft Notice of Final Rulemaking. Copies of the 
stakeholder’s comments are attached to this report.

Maricopa County 
Air Quality Department 
Planning and Analysis Division 
Report to the 
Board of 
Supervisors 
 
Rule 205 (Emission 
Offsets Generated by 
Voluntary Mobile 
Source Emission 
Reduction Credits) 
May 2025

Board of Health  
Email Notification:  
September 3, 2024 
Board Hearing Date: 
May 21, 2025 
Case Number/Title: 
AQ-2024-004-Rule 205 (Emission Offsets Generated by 
Voluntary Mobile Source Emission Reduction Credits) 
Agenda Item: 
(Pending) 
Supervisor Districts: 
All Districts 
Applicant:  
Staff 
Request: 
Approve revision of Maricopa County Air Pollution Control 
Regulations, Rule 205 (Emission Offsets Generated by 
Voluntary Mobile Source Emission Reduction Credits), the 
proposed submission of the amended rule as a revision to 
the Arizona state implementation plan (SIP), and the 
withdrawal of the May 4, 2023, Rule 205 SIP submittal. 
Maricopa County is currently designated as a nonattainment 
area for both the 2008 8-hour ozone National Ambient Air 
Quality Standard (NAAQS) and the 2015 8-hour ozone 
NAAQS. It is classified as a moderate nonattainment area 
for both the 2008 8-hour ozone NAAQS and 2015 ozone 8-
hour NAAQS. In ozone nonattainment areas, the Clean Air 
Act (CAA) under the New Source Review program requires 
an owner or operator proposing to construct a new major 
source or proposing to construct a major modification of an 
existing major source to obtain emission offsets that exceed 
emission increases from the proposed project before the 
project may commence. In the case of an ozone moderate 
nonattainment area, such as Maricopa County, the CAA 
requires an owner or operator proposing to construct a new 
major source or proposing to construct a major modification 
of an existing major source to obtain 1.15 tons of emission 
offsets for every 1.0 ton of proposed emission increases 
from the project. 
Currently, insufficient emission reduction credits, which can 
be used as emission offsets, exist to permit large new or 
existing modified projects in Maricopa County. As a result, 
Rule 205 was created and adopted by the Board of 
Supervisors on April 26, 2023. The purpose of Rule 205 is to 
allow for the generation and certification of mobile source 
emission reduction credits (MERCs) for use as emission 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 7 of 125

offsets through voluntary captive fleet vehicle replacement 
or retrofit. 
The purpose of the rulemaking is to remedy deficiencies 
identified by the U.S. Environmental Protection Agency (EPA) 
and to address stakeholder comments. On May 4, 2023, 
MCAQD submitted Rule 205 to the EPA for approval into the 
Arizona SIP. EPA reviewed Rule 205 and identified 
deficiencies which precluded approval of Rule 205 into the 
SIP. MCAQD has worked with the EPA to adequately address 
the deficiencies. 
Additionally, MCAQD received stakeholder feedback 
proposing an additional rule revision under Appendix A 
whereby baseline emissions are determined using the 
original vehicle engine model year. This revision is not part 
of the revisions to address the EPA identified deficiencies. 
This proposed revision will allow a greater amount of MERCs 
to be calculated thereby creating a greater incentive for 
captive fleet owners to replace or retrofit old, higher NOx 
emitting vehicles. Rule 205 was developed as an economic 
incentive program and the only way to make it an effective 
incentive program is by revising the MERC calculation to use 
the emissions of the original vehicle. 
Support/Opposition: 
During the rulemaking process, MCAQD received written 
feedback from two stakeholders who expressed neither 
support nor opposition to the rulemaking. MCAQD 
representatives met with each stakeholder and worked with 
them to address their comments. 
Staff 
Recommendation: 
Approve 
Board of Health 
Recommendation: 
Approve 
Additional Comments: 
This regulatory change is following the Enhanced Regulatory 
Outreach Program (EROP) Policy and workflow process. The 
County Manager briefed the Board of Supervisors regarding 
this rulemaking on November 2, 2021, and April 8, 2024. 
Stakeholder Workshops were held on January 22, 2022, 
November 2, 2022, and September 17, 2024. 
The Board of Health approved initiation of regulatory change 
on January 24, 2022, a Notice of Proposed Rulemaking was 
posted on the EROP website on December 7, 2022, and the 
Board of Health recommended approval to the Board of 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 8 of 125

Supervisors on January 23, 2023. The Board of Supervisors 
adopted the rule on April 26, 2023, and MCAQD submitted 
the rule to the EPA on May 4, 2023. 
Upon feedback from the EPA and continuation of the EROP 
policy workflow, an email notification was sent to the Board 
of Health on September 3, 2024, and a second Notice of 
Proposed Rulemaking was posted on the EROP website on 
February 26, 2025. 
A newspaper notice of the Board of Supervisors public 
hearing will be published in the Arizona Business Gazette on 
April 10, 2025, and April 17, 2025. 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) 
Summary of the proposed regulatory change (See Item 4 of 
the Draft Notice of Final Rulemaking) 
Analysis of input received during the process and how 
that input was responded to (See Item 9 of the Draft 
Notice of Final Rulemaking) 
Language of proposed regulatory change or amendment 
(See the Draft Notice of Final Rulemaking) 
Minutes from Board of Health meeting - January 24, 2022 
Copies of all written and electronic Stakeholder input 
Working Draft Rule 205_Strikethrough
Working Draft Rule 205_Clean
Minutes from Board of Health meeting - January 23, 2023 
Board of Health Notification for MCAQD Rules 204 and 205 - 
September 3, 2024 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 9 of 125

Maricopa County 
Air Quality Department 
Planning and Analysis Division 
Draft Notice of Final 
Rulemaking 
Rule 205 (Emission Offsets 
Generated by Voluntary 
Mobile Source Emission 
Reduction Credits) 
May 2025

Draft Notice of Final Rulemaking 
Maricopa County Air Pollution Control Regulations 
Regulation II – Permits and Fees 
Rule 205 (Emission Offsets Generated by Voluntary Mobile Source 
Emission Reduction Credits) 
The Maricopa County Air Quality Department (MCAQD) is proposing to amend Rule 205 
(Emission Offsets Generated by Voluntary Mobile Source Emission Reduction Credits). 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 Arizona Revised Statute (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(B). 
Preamble 
1.
Statutory authority for the rulemaking (A.R.S. § 49-471.05(1)):
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 (A.R.S. § 49-471.05(2)):
Name:
Will Adrian or Kimberly Butler 
Maricopa County Air Quality Department 
Planning and Analysis Division 
Address: 
301 W. Jefferson St., Suite 410 
Phoenix, AZ 85003 
Telephone: 
602-506-6010 
Fax: 
602-506-6179 
Email: 
AQPlanning@maricopa.gov 
Online: 
Submit a Comment 
3.
Rulemaking process (A.R.S. § 49-471.05(3)):
This rulemaking is following procedures identified in state statutes and the Maricopa
County EROP Policy.
Return to list of attachments
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 11 of 125

First County Manager Briefing: 
November 2, 2021 
Stakeholder Workshops:  
January 10, 2022 
November 2, 2022 
Board of Health Meeting to Initiate Regulatory 
Change:  
January 24, 2022 
First Notice of Proposed Rulemaking: 
December 7, 2022 
Board of Health Meeting to Recommend Approval 
to the Board of Supervisors:  
January 23, 2023 
First Board of Supervisors Formal Meeting to Set 
the Public Hearing:  
March 15, 2023 
First Board of Supervisors Public Hearing: 
April 26, 2023 
Arizona State Implementation Plan (SIP) 
Revision Submittal: 
Second County Manager Briefing: 
EPA Proposed Conditional Approval: 
Email Notification to Board of Health: 
Stakeholder Workshop: 
Second Notice of Proposed Rulemaking: 
May 4, 2023 
April 8, 2024 
August 22, 2024  
September 3, 2024 
September 17, 2024  
February 26, 2025 
Second Board of Supervisors Formal Meeting to 
Set the Public Hearing: 
April 9, 2025 
Second Board of Supervisors Public Hearing: 
May 21, 2025 
4.
Explanation of the rule, including the control officer's reasons for initiating the
rulemaking (A.R.S. § 49-471.05(4)):
Maricopa County is currently designated as a nonattainment area for both the 2008 8-
hour ozone National Ambient Air Quality Standard (NAAQS) and the 2015 8-hour ozone
NAAQS. It is classified as a moderate nonattainment area for both the 2008 8-hour
ozone NAAQS and 2015 ozone 8-hour NAAQS. In ozone nonattainment areas, the Clean
Air Act (CAA) under the New Source Review program requires an owner or operator
proposing to construct a new major source or proposing to construct a major
modification of an existing major source to obtain emission offsets that exceed
emission increases from the proposed project before the project may commence. In the
case of an ozone moderate nonattainment area, such as Maricopa County, the CAA
requires an owner or operator proposing to construct a new major source or proposing
Return to list of attachments
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 12 of 125

to construct a major modification of an existing major source to obtain 1.15 tons of 
emission offsets for every 1.0 ton of proposed emission increases from the project. 
Currently, insufficient emission reduction credits, which can be used as emission 
offsets, exist to permit large new or existing modified projects in Maricopa County. As a 
result, Rule 205 (Emission Offsets Generated by Voluntary Mobile Source Emission 
Reduction Credits) was created and adopted by the Board of Supervisors on April 26, 
2023. The purpose of Rule 205 is to allow for the generation and certification of mobile 
source emission reduction credits (MERCs) for use as emission offsets through 
voluntary captive fleet vehicle replacement or retrofit.  
On May 4, 2023, the rule was submitted to the U.S. Environmental Protection Agency 
(EPA) for approval into the Arizona State Implementation Plan (SIP). On March 25, 2024, 
the EPA sent MCAQD a letter identifying deficiencies and issues in the rule that would 
prevent full approval of the rule into the Arizona SIP. In the letter, the EPA stated they 
may grant conditional approval of Rule 205 under section 110(k)(4) of the Clean Air Act 
based on a commitment by the state to adopt and submit specific enforceable 
measures within one year of the EPA's final conditional approval. 
On May 6, 2024, MCAQD submitted a Letter of Commitment for Conditional Approval of 
Rule 205 through the Arizona Department of Environmental Quality (ADEQ) to EPA. The 
letter outlined MCAQD’s commitments to address each deficiency and issue identified 
in EPA’s comment letter. 
Based on the commitment letter, the EPA published a proposed conditional approval of 
Rule 205 in the Federal Register on August 22, 2024 (Docket ID No.: EPA–R09–OAR–
2024–0311). The proposed conditional approval rulemaking was available for a 30-day 
comment period, ending September 23, 2024. The proposed conditional approval 
references a Technical Support Document (TSD) which includes a thorough review of 
Rule 205 and MCAQD’s commitments. Revisions addressing both the EPA’s identified 
deficiencies and issues have been made to the proposed draft Rule 205 (included in this 
notice). A link to EPA’s TSD is located under Section 5 of this notice. 
It is important to note that Rule 205 is considered an economic incentive program (EIP). 
An EIP, as described by EPA’s EIP guidance document titled “Improving Air Quality with 
Economic Incentive Programs” (link in Section 5), is a regulatory program that achieves 
an air quality objective by providing market-based incentives. MCAQD developed Rule 
205 with the objective to provide owners and operators of captive fleet vehicles with a 
market-based incentive to replace or retrofit older, high NOx emitting vehicles with 
newer vehicles using a lower-emitting fuel. By replacing or retrofitting older, high NOx 
emitting vehicles with newer vehicles using a lower-emitting fuel, captive fleet owners 
can obtain emission reduction credits which they can then sell as emission offsets to 
businesses looking to relocate or expand in Maricopa County 
In response to stakeholder feedback MCAQD is proposing an additional rule revision 
under Appendix A whereby baseline emissions are determined using the original vehicle 
engine model year. This revision is not part of the revisions to address the EPA 
identified deficiencies. This proposed revision will allow a greater amount of MERCs to 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 13 of 125

be calculated thereby creating a greater incentive for captive fleet owners to replace or 
retrofit old, higher NOX emitting vehicles.  
In the version of Rule 205 submitted to the EPA on May 4, 2023, the calculated MERCs 
is based on the difference between the emissions of a new model year vehicle and the 
emissions of a replacement vehicle using a lower-emitting fuel. The calculations do not 
account for emission reductions from the replacement or retrofit of vehicles older than 
a new model year vehicle. For example, replacing a 2008 diesel vehicle with a 2024 
compressed natural gas (CNG) vehicle would only generate MERCs that account for the 
difference in emissions from a new 2024 diesel vehicle and the 2024 CNG vehicle. 
MCAQD is proposing the calculated MERCs be based on the difference between the 
emissions of the original vehicle (the vehicle which is replaced or retrofitted), taking into 
account age-based deterioration and older federal emission standards, and the lower-
emitting fueled replacement vehicle. Using the emissions of the original vehicle for the 
MERC calculation will allow a greater amount of MERCs to be calculated and provide a 
real incentive to replace or retrofit older high emitting NOx vehicles in Maricopa County. 
Rule 205 was developed as an economic incentive program and the only way to make it 
an effective incentive program is by revising the MERC calculation to use the emissions 
of the original vehicle. 
Because EPA’s conditional approval did not take into account a revision to the Rule 205 
calculation methodology, MCAQD is planning to withdraw the May 4, 2023, SIP 
submittal and replace it with a new Rule 205 SIP submittal where the EPA’s identified 
deficiencies are addressed and the revised calculation methodology is included.  
Details about the EPA’s identified rule deficiencies and MCAQD’s proposed remedies 
are described below, followed by EPA EIP support document elements and MCAQD’s 
commitments to address each in a Rule 205 EIP support document.  
Comment 1: 
Applicability of Rule 205 to Ozone Precursors: Throughout the rule, the term 
“conventional air pollutants” is used. This term is defined in Section 200.34 of Rule 100 
– General Provisions and Definitions [MCAPCR], as a pollutant for which a national
ambient air quality standard (NAAQS) has been promulgated, including any precursors 
to such pollutants. The use of this term would presumably allow Mobile Source  
Emission Reduction Credits (MERCs) to be generated for any NAAQS pollutant, while 
Maricopa County is only designated nonattainment for the 2008 and 2015 ozone 
NAAQS, and the 1987 PM10 NAAQS. Due to several technical issues with calculating 
PM10 emissions reductions from mobile sources, the rule must be revised to specify 
that MERCs may only be generated for the ozone precursors of nitrogen oxides and 
volatile organic compounds. 
Remedy 1: 
MCAQD is proposing to revise the definition for qualifying emissions, Section 218, to 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 14 of 125

limit the generation of MERCs to the ozone precursors of nitrogen oxides (NOx) and 
volatile organic compounds (VOCs). 
Comment 2: 
Rule Definitions, Consistent Terminology and Enforceability: CAA Section 110(a)(2) 
requires all rules incorporated into a SIP to be enforceable. There are several parts of 
the rule where the current text is not clear, which can lead to confusion as to how 
certain provisions of the rule are to be carried out and enforced. Here we comment on 
two specific issues. 
a. Defining vehicle types: The rule relies on specific pieces of data from three
different vehicles that would be involved in each proposed emission
generating project; (1) the original fleet vehicle that is to be replaced or
retrofitted, (2) the regulatory baseline vehicle, which is an equivalent (size,
fuel, and type of vehicle) current implementation model year replacement for
the original vehicle that provides the emissions baseline to calculate the
emissions reduction, and (3) the actual retrofitted or replacement vehicle
which provides the cleaner vehicle emission data. Defining these as distinct
terms in the rule is essential to differentiate each type of vehicle and then use
these terms consistently throughout the rule.
b. Defining and distinguishing MERC terminology: The rule currently uses
various terms, such as “certified credits” and “MERCs”, to describe the
emissions reductions for which a tradable credit may be issued. It appears
the rule uses the terms “certified credits” and “MERCs” almost
interchangeably, although they are defined differently (See definition for
“Certified Emission Reduction Credits” and “MERCs”).
The rule must be revised to provide clear and consistent usage of the terms
used to describe emission reductions, along with appropriate definitions for
each term. We suggest revising the rule as necessary to make clear that the
process is for the Department to evaluate proposed reductions in qualifying
emissions, certify the reductions if they meet the certification criteria and
issue MERC certificates for the certified quantity of qualified emission
reductions.
Remedy 2a. 
 MCAQD is proposing to create a new definition for original vehicle (Section 216) and 
revise the definitions for replacement vehicle (Section 221) and retrofit vehicle (Section 
222) and revise the rule to ensure these terms are used consistently throughout the rule. 
Remedy 2b. 
MCAQD is proposing to revise MERC terminology by removing the definition for certified 
emission reduction credit and creating a new definition for MERC certificate (Section 
211), and consistently using the term MERC throughout the rule to represent a tradable 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 15 of 125

credit. MCAQD is also proposing to implement these terms more consistently in the rule 
to distinguish between evaluation of qualifying emissions, certification of emission 
reductions, and issuance of MERC certificates. 
Comment 3 
MERC Certificate Content: To ensure the permit authority, the EPA, and the public can 
evaluate whether a MERC surrendered as a New Source Review (NSR) offset meets the 
offset integrity criteria found in 40 CFR 51.165(a)(3)(ii)(C)(1)(i) at the time of NSR 
permit issuance, the rule must specify the minimum contents of each MERC certificate. 
The certificate must include all the specific data for the particular qualified emission 
reductions, such as, but not limited to: MERC certificate number, date of issuance, name 
and address of the generator, description of activity that resulted in the qualified 
emission reductions, the quantity of emission reductions certified for each pollutant, the 
vehicle miles travelled (VMT) and Motor Vehicle Emission Simulator (MOVES) emission 
factors used for the calculations, a statement that the MERC does not provide any 
property rights, and a statement that the new source relying on the emissions offsets 
from a MERC may not commence operation until the emissions reductions 
corresponding to that MERC have actually occurred. 
Remedy 3 
MCAQD is proposing to revise the rule to include the contents of each MERC certificate. 
Section 301.3 b.(2) in the draft rule lists the specific data that must be included in the 
MERC certificate which includes the following: MERC certificate number, date of 
issuance, name and address of the generator, description of activity that resulted in the 
qualified emission reductions, the quantity of emission reductions certified for each 
pollutant, the vehicle miles travelled (VMT) and Motor Vehicle Emission Simulator 
(MOVES) emission factors used for the calculations, a statement that the MERC does 
not provide any property rights, and a statement that the new source relying on the 
emissions offsets from a MERC may not commence operation until the emissions 
reductions corresponding to that MERC have actually occurred. 
Comment 4 
Relocation and Disposal of Baseline Vehicles: Section 302.2c. – Removal/Disposal of 
Replaced Baseline Vehicles, currently requires disposal of the vehicles for which a 
MERC is issued, in part to satisfy the requirement of 40 CFR 51.165(a)(3)(ii)(C)(1)(i) that 
emission reductions used for offsets must be permanent. Options for disposal currently 
include rendering the fleet vehicles permanently disabled and disposed of, or 
permanently removing the vehicles at least 200 miles from the Phoenix-Mesa ozone 
nonattainment area. While disabling and disposing of an engine is the best way to 
ensure the replaced vehicle will no longer operate in the Phoenix-Mesa ozone 
nonattainment area, we believe relocating the vehicles at least 200 miles outside the 
Phoenix-Mesa ozone nonattainment area is acceptable if additional restrictions are 
imposed on the final location of those vehicles. The rule must specify that vehicles 
relocated out of the Phoenix-Mesa ozone nonattainment area must not be relocated to 
any other ozone nonattainment area, as designated on the date a MERC certificate is 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 16 of 125

issued. 
Remedy 4 
 MCAQD is proposing to revise Section 302.2 c. to add additional restrictions on 
relocation whereby original vehicles relocated outside of the Phoenix-Mesa ozone 
nonattainment area must not be relocated to any other ozone nonattainment area, as 
designated on the date of MERC issuance. 
Comment 5 
Determining and Documenting Annual Utilization Rates: 40 CFR 51.165(a)(3)(ii)(C)(1)(i) 
requires emission reductions to be quantifiable. Rule 205 requires the applicant to 
supply the annual average miles that the original fleet vehicles were utilized within the 
nonattainment area, and to monitor and record the VMT for each new fleet vehicle on an 
annual basis. The VMT data is critical for determining the quantity of MERCs issued and 
to verify that the certified number of actual emission reductions are being achieved. 
Section 301.1b.(4) requires an application to include “Information on the methodology 
for quantifying the surplus reductions in qualifying emissions for each pollutant subject 
to the application, including emissions calculations.” The rule does not contain 
sufficient requirements to provide the annual average utilization rate for each vehicle 
included in the proposed project, nor any requirement to document how these rates 
were determined. Rule 205 must specify that the application include information 
documenting the activity level claimed by the applicant. 
Remedy 5 
MCAQD is proposing to revise the MERC application requirements under 301.1 a.(4) to  
require the applicant to provide documentation of each original vehicle’s historic vehicle 
miles traveled, and how these rates were determined. 
Comment 6 
Installation and Operation of Fleet Monitoring System: 40 CFR 51.165(a)(3)(ii)(C)(1)(i) 
requires emission reductions to be federally enforceable. Section 503 contains 
monitoring provisions for permitted generators and requires the VMT for each fleet 
vehicle to be monitored “as determined by GPS tracking.” The rule does not define what 
constitutes “GPS tracking.” Generally, a fleet owner would install and operate a 
complete fleet monitoring system to provide GPS tracking. To ensure enforceability of 
the emission reductions, the rule must contain requirements for the installation, 
operation and maintenance of a defined GPS tracking device and software system that 
will monitor and record VMT data, including whether the VMT occurred within the 
specific nonattainment area, in addition to the general operation and maintenance 
requirements in Section 503. These requirements must include provisions to require 
operation in accordance with manufacturer’s instructions/specifications, including a 
requirement to periodically update the software and maps used by the GPS tracking 
system. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 17 of 125

Remedy 6 
MCAQD is proposing to remove the term “GPS tracking” and to add a new term “Fleet 
Management System” (defined in Section 207) which will be used in place of “GPS 
tracking”. MCAQD is also proposing revisions to the location tracking equipment and 
software system requirements under Section 302.2 b. Fleet Management System. This 
includes requirements for regular system updates, operation and maintenance in 
accordance with manufacturer’s instructions, and installation of a system that can 
differentiate and record travel in and out of the nonattainment area. 
For generators that operate entirely within the nonattainment area, MCAQD is proposing 
to add an exemption from complying with the fleet management system requirements 
of § 302.2 b.(1). The generator must submit to the Control Officer for approval, 
documentation demonstrating the operations occur entirely within the nonattainment 
area. In addition, the generator must demonstrate how the monthly VMT will be 
monitored and recorded in absence of a fleet management system. 
Comment 7 
Data Used to Calculate Emissions Reductions: Appendix A.3. specifies that the 
“Baseline Pollutant Emissions Factor” is determined by using the “on-road vehicle 
emissions factors, in g/mile, in the latest applicable version of the United States 
Environmental Protection Agency’s (EPA) Motor Vehicle Emission Simulator (MOVES) 
software.” However, the “on-road vehicle emission factor, in g/mile” for a specific year, 
fuel, and class of vehicle is one that the MOVES software generates as a modeled 
output, after it factors in various local condition inputs. In order for the program to be 
based on current emissions factors, the rule must be revised to state that the g/mile 
emission factor is to be determined, for each project, using the latest version of MOVES. 
Additionally, the EIP support document must specify the MOVES input data fields to be 
used, how the MOVES software will be run, and that the Department will utilize the latest 
version of MOVES to calculate the creditable quantity of qualifying emission reductions. 
The EIP support document should explain how the generator will obtain the MOVES 
generated emission factor data to be used in their application. 
Remedy 7 
MCAQD is proposing to revise Appendix A so the on-road vehicle emissions factor is 
determined by running the latest version of MOVES, as well as requiring the data points 
needed to run MOVES. 
MCAQD will also correct this deficiency by specifying in the EIP support document the 
MOVES input data fields to be used, how the MOVES software will be run, and that 
MCAQD will utilize the latest version of MOVES to calculate the creditable quantity of 
qualifying emission reductions. The EIP support document will also explain how the 
generator will obtain the MOVES-generated emission factor data to be used in their 
application. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 18 of 125

Comment 8 
Notification of Implementation of Emission Reductions: Section 173(c)(1) of the CAA, 
regarding NSR offsets, states that emission reductions shall be in effect and 
enforceable by the time a new or modified source commences operation. Rule 205 
allows a MERC certificate to be issued to the permitted generator based on their 
proposed emission reduction project, rather than a completed emission reduction 
project. Section 301.2c.(3) states that if the project has not been completed when the 
Department is prepared to issue a MERC certificate, then the MERC certificate must 
include a future completion date for the project. Section 301.2c.(1) requires the permit 
to incorporate the requirements of Section 302.2, but does not specify that a future 
completion date for the project be included in the permit. Rule 205 must be revised to 
require this date be included in the permit. 
Section 304.1d. further provides that “Reductions in qualifying emissions reflected in 
the number of certified credits shall be implemented before actual operation of the new 
stationary source or modification begins.” While this provision is found under the rule 
section entitled “Use of the Certified Credits,” it is not clear who this provision applies to 
as only the permitted generator can implement the required reductions in qualifying 
emissions, but it is the credit user that is restricted from operating prior to the MERC 
generating project being fully implemented. This provision must be clarified to clearly 
state that the credit user cannot commence operation until the project to reduce 
qualifying emissions has been completed. 
In turn, to ensure successful implementation and enforcement of the program, the rule 
must provide a mechanism to ensure that the public and credit user know when the 
credit generating project for any particular MERC certificate has been fully 
implemented. In addition, to track the implementation of MERCs and compliance with 
the NSR permit, the rule must include a requirement for the permitted generator to notify 
the Department when all replacement and/or retrofitted vehicles are in operation and all 
original vehicles have been properly removed or destroyed. Any mechanism for 
notifying the Department that the project has been completed must include the 
submittal of supporting documentation to demonstrate compliance with this 
requirement. Additionally, this completion notification should be provided to the credit 
user to document that the emissions reduction project generating the credits for their 
MERC certificate has been completed and that their project may commence operation. 
Remedy 8 
MCAQD is proposing to include the date by which qualifying emission reductions are 
required to be implemented, under Section 301.3 b.(1)(c), in the generator’s new or 
revised permit. MCAQD is also proposing to add Section 303.3 to clearly state that the 
credit user cannot commence operation until the generator has demonstrated the 
project to reduce qualifying emissions has been completed. Additionally, MCAQD is 
proposing a new requirement under Section 401.1 for the generator to notify MCAQD 
and the credit user when completion of implementation of qualifying emission 
reductions for MERCs has taken place. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 19 of 125

Comment 9 
Requirements for Users of Certified Credits: Rule 205 Section 102.2 states that the rule 
applies to owners or operators of a permitted stationary source that intend to use 
certified credits as offsets, but the rule does not provide a rule section to specify the 
requirements for credit users. Instead, these requirements are interwoven throughout 
the rule. We suggest gathering these requirements into one section of the rule. At a 
minimum, the rule must include provisions for the credit user that include the following 
requirements: (1) the certified credits (MERCs) must be surplus when their permit is 
issued, not as of the application submittal date; (2) the credit user may not commence 
operation until the permitted generator has submitted to the Department the necessary 
documents to demonstrate the MERC project was completed; (3) if notified of a VMT 
shortfall, the credit user must evaluate the VMT shortfall against the credit user’s actual 
12-month rolling emissions from the project that relied on the MERCs as offsets; and (4) 
the credit user must make up any actual emission reduction shortfall that occurs. This 
rule section must also provide options for the credit user to make up any shortfalls. 
Remedy 9 
MCAQD is proposing language in Section 303.2 that the Control Officer verify MERCs 
remain surplus prior to permit issuance. In Section 303.3, MCAQD is proposing 
language prohibiting the credit user from commencing operation until the permitted 
generator has submitted the necessary documents to the MCAQD to demonstrate the 
MERC project was completed. Additionally, MCAQD is proposing to consolidate credit 
user shortfall requirements under Sections 401.3. This section includes credit user 
requirements if a credit shortfall impacting the integrity of the MERCs is determined and 
options to address the shortfall.  
The intent of determining a VMT shortfall is to identify whether the generator is shifting 
baseline MERC vehicle activity level operations to a higher emitting vehicle, which would 
invalidate all or a portion of the issued MERCs. MCAQD is proposing to include a 
demonstration of continued compliance requirement, whereby the generator may 
provide demonstration to the Control Officer showing that the lower VMT was not a 
result of load shifting and the integrity of the MERCs continue. If the demonstration is 
approved by the Control Officer no further action is required. If the demonstration does 
not receive approval, the generator must notify the credit user who must then comply 
with the applicable VMT shortfall requirements in § 401.3. 
Comment 10 
Off-road vehicles: The rule provides that qualifying emission reductions can be 
generated from either on-road or off-road vehicles. However, the calculation procedures 
provided in Appendix A only apply to on-road vehicles. In addition, since off-road 
vehicles are not registered, there are other issues related to ensuring any emission 
reductions are surplus and demonstrating these vehicles are permanently removed 
from the nonattainment area. Therefore, until these issues can be addressed, the off-
road vehicle provisions in Rule 205 must be removed to ensure Rule 205 is fully 
approvable. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 20 of 125

Remedy 10 
MCAQD is proposing to remove the off-road vehicle provisions in Rule 205. 
Comment 11 
Reductions Occurring in EJ Communities: Appendix A, paragraph D. contains a 
provision which would allow a vehicle fleet located in an Environmental Justice (EJ) 
community to calculate the baseline emissions using the original fleet vehicle rather 
than a current model year vehicle. The rule requires use of current model year vehicle 
emissions as the baseline for granting ERCs to ensure the reductions are surplus to 
other attainment plan provisions that already take credit for fleet turnover. Since the use 
of an earlier model year vehicle as the baseline for calculating emission reduction 
credits would not ensure these reductions are surplus, this provision must be removed 
from the rule. 
Remedy 11 
MCAQD is proposing to remove the High Pollution Area Incentive in Appendix A, 
paragraph D. from the rule. 
Comment 12 
Base Year Inventory: The 2015 ozone attainment plan is based on a 2017 baseline 
emission inventory that includes input from the MOVES model using 2017 vehicle data. 
Therefore, credit cannot be given for any fleet conversion that occurred prior to 2017 or 
for any emission reductions the MOVES model has already credited for the 
transportation conformity demonstration. Rule 205 must explicitly contain this 
restriction. 
Remedy 12 
MCAQD is proposing to revise the definition of Qualifying Emissions so that credit 
cannot be given for fleet conversions that occurred prior to 2017. 
Comment 13 
Monitoring, Recordkeeping, and Reporting Requirements: CAA section 110(a)(2)(A) 
requires the elements of a SIP, including economic incentive programs, to be 
enforceable. 40 CFR 51.165(a)(3)(ii)(C)(1)(i) requires emissions reductions to be 
surplus, permanent, quantifiable, and federally enforceable to be creditable offsets. Rule 
205 must therefore require sufficient monitoring, recordkeeping, and reporting 
provisions to ensure that the permitted generators and credit users are in compliance 
with the regulatory requirements and permit conditions, and it must provide that 
compliance data is made available to the public. While Rule 205 contains most of these 
provisions, additional specificity needs to be included. Section 503 – MERC Generation 
Monitoring, requires the generator to “monitor” certain information, but Section 504.3 
needs further clarification to state the frequency of such monitoring, and requirements 
to retain a record of the monitored data. Rule 205 must be revised to provide more 
Maricopa County • Air Quality Department • Rule 205  Report to the Board of Supervisors
Page 19 of 123
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 21 of 125

specificity to these two provisions. 
Section 504 – MERC Generation Records, requires the generator to maintain all records 
supporting their application for certified credits, and includes a list of minimum records 
requirements. However, the specified records may not be available at the time of 
application if a proposed emission generating project was not completed prior to 
application, as allowed by the rule. Because the rule provides the option to obtain a 
MERC prior to project completion, the language in this provision must be revised to 
ensure all records pertaining to the credit generation are maintained by the applicant 
and the Department even if they were not included in the original application. See 
Section 4.1(a) of the Federal EIP Guidance for additional information. 
Remedy 13 
MCAQD is proposing to add specificity to Section 503 that monitoring shall begin no 
later than the issuance of the MERC certificate or enforceable date within the permit. 
MCAQD is also proposing to add additional specificity to Section 504.3 for monthly 
monitoring of VMT and a requirement to keep a summary of these records and any 
other monitoring of Section 503. MCAQD is proposing to revise Section 504.1 to ensure 
all records pertaining to the credit generation are maintained. 
Comment 14 
Demonstrating Permanence: Section 503 – MERC Generation Monitoring, requires the 
generator to “monitor” the VMT for each replaced or retrofitted vehicle, but the rule does 
not contain any provisions which require the generator to continue to achieve the annual 
average VMT that was the basis for granting the MERC certificate. In part, permanence 
is assured by requiring the new fleet vehicles to achieve the same activity levels as the 
old fleet, which is demonstrated by ensuring the VMT for the new fleet remains at the 
same level or higher. Rule 205 is deficient because the rule does not require a fleet 
operator to demonstrate that they are achieving the same VMT used as the basis for 
granting their MERC certificate, which is inconsistent with enforceability requirements in 
CAA section 110(a)(2)(A) and 40 CFR 51.165(a)(3)(ii)(C)(1)(i). Rule 205 must be 
amended to require the generators ongoing compliance with the activity level that was 
the basis for MERC certificate issuance. 
Remedy 14 
MCAQD is proposing to require the generator demonstrate that they are achieving the 
same VMT used as the basis for granting their MERC certificate by adding Section 505 
Compliance Demonstration, where the generator is required to calculate a twelve-month 
rolling total of VMT. MCAQD is additionally proposing that the generator compare this 
VMT against their historic VMT under added Section 401.2, whereby the generator 
compares the twelve-month rolling VMT against the VMT specified in the MERC 
certificate. 
NOTE: As mentioned earlier, some of the EPA identified deficiencies and issues must be 
addressed in an EIP support document. Most of the final comments included in EPA’s 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 22 of 125

comment letter address EIP support document requirements although there are a few 
rule requirements included. Below is a list of the final comments in EPA’s comment 
letter and MCAQD’s proposals to address the comments. 
Comment 15 
Identifying Violations: Section 110(a)(2)(A) requires the elements of a SIP, including 
economic incentive programs, to be enforceable. The regulations at 40 CFR 51.165 
require emissions reductions to be surplus, permanent, quantifiable, and federally 
enforceable to be creditable offsets. Rule 205 relies on language that the generator or 
user “shall” or “must” do specific things, such as comply with the operating, 
maintenance, monitoring, removal/disposal, replacement, and recordkeeping 
requirements listed in Section 302.2. Thus, it would be a violation of the rule to not 
perform the required actions. At a minimum, the EIP support document must contain a 
robust discussion of how the Department will determine rule and program violations. 
The Department has raised concerns regarding the permitted generator being in 
violation of the requirement to achieve a certain VMT if in fact they are still achieving 
more emission reductions than the credit user is emitting in any 12-month period. 
Accordingly, the EPA believes that it is appropriate for the rule to include a two-step 
process to determine if a shortfall in VMT resulted in fewer emission reductions than 
the actual emission increases the credit user generated over the same 12-month period. 
The rule could provide that the generator is in violation of the requirement to generate a 
specific quantity of fleet VMT if two conditions are met: (1) the VMT achieved for any 
rolling 12-month period is less than the annual fleet VMT for which the MERC certificate 
was issued, and (2) the actual emissions generated by the permitted generator using 
these specific MERCs over the same time period are more than the emission reductions 
achieved by the actual VMT achieved. We believe this compliance option will provide 
some flexibility for both the permitted generator and credit user while still ensuring no 
adverse impacts to air quality. See Section 4.1(a) of the Federal EIP Guidance for 
additional information. 
Remedy 15 
MCAQD will correct this deficiency by explaining in the EIP support document how 
MCAQD will identify rule and program violations. 
Comment 16 
Penalty Provisions for Violations of the Rule: Rule 205 or the Department’s EIP support 
document must include provisions for imposing penalties for violations. The EIP 
support document must explain what constitutes a violation of Rule 205 and the 
procedures the Department will use to determine the magnitude of a violation and how 
potential penalties will be determined. The Department must demonstrate in the 
program support document that it has the authority and ability to impose a maximum 
monetary penalty of at least $10,000 per day per violation. The EIP support document 
must specify that it is a violation each and every day within the averaging period if a 
source does not meet any requirements of the rule (e.g., not creating sufficient 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 23 of 125

emission reductions, etc.) and specify the source may be subject to a monetary penalty 
of up to $10,000 per day per violation. The Department must retain the right to impose 
and collect a monetary penalty, although you do not need to exercise this right for all 
violations. See Sections 5.1(c) and 6.1 of the Federal EIP Guidance for additional 
guidance on the enforcement elements to be included in the Department’s EIP. 
Remedy 16 
MCAQD will correct this deficiency by including the following in the EIP support 
document: (a) a description of how penalties are imposed for violations, (b) a 
description of what constitutes a violation of Rule 205 and the procedures MCAQD will 
use to determine the magnitude of a violation and how potential penalties will be 
determined, (c) a demonstration of the MCAQD’s authority and ability to impose a 
maximum monetary penalty of at least $10,000 per day per violation, and (d) an 
explanation that it is a violation each and every day within the averaging period if a 
source does not meet any requirement of the rule and provisions specifying that a 
source may be subject to a monetary penalty of up to $10,000 per day per violation. 
MCAQD will retain the right to impose and collect monetary penalties. 
Comment 17 
Additional EIP Elements: This section lists provisions that we believe are needed for an 
EIP to be approved into the SIP. These provisions can be provided as a narrative in the 
EIP support document or in the rule, as noted below. See Section 5.1 of the Federal EIP 
Guidance for additional information. 
a.
A discussion and demonstration of the environmental benefits of the
Department’s EIP. See Section 6.5(a) of the Federal EIP Guidance for
additional information.
b.
Because the Department’s EIP is a trading program that allows VOC HAPs
to be shifted from one facility to another, the EIP support document must
address certain elements related to VOC HAP emissions, including: (1)
options for preventing and/or mitigating impacts from potential or actual
trades involving HAPs; (2) what information will be made available for
meaningful review and participation by the public; and (3) periodic
program evaluations of the impacts of VOC HAP trades on the health and
environment of local communities. See Section 16.2(b) of the Federal EIP
Guidance for additional information.
c.
To avoid potential conflicts with EPA’s or citizens’ CAA enforcement
authorities, Rule 205 must include the following statement in the section
of the rule discussing enforcement: “Nothing herein restricts independent
enforcement authorities under the Clean Air Act by other parties.” See
Section 5.1(c) of the Federal EIP Guidance for additional information.
d.
The Department’s EIP must ensure that the public has access to
emissions related information in a manner that allows them to easily and
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 24 of 125

accurately calculate the emissions or data relevant to the enforceable 
requirements of each participating source (i.e., both the credit generator 
and user). Rule 205 must contain a provision allowing the Department to 
obtain from the participating sources, all information necessary to 
calculate every source’s emissions (tonnage). How this information will be 
provided to the public may be included in the EIP support document as 
opposed to the rule. 
Remedy 17 
MCAQD will correct the corresponding deficiencies outlined in the EPA’s March 25, 
2024 letter as follows: 
a.
MCAQD will correct this deficiency by providing a discussion and
demonstration of the environmental benefits of the MCAQD’s EIP in the
EIP support document.
b.
MCAQD will correct this deficiency by addressing the following elements
in the EIP support document: (1) options for preventing and/or mitigating
impacts from potential or actual trades involving HAPs; (2) what
information will be made available for meaningful review and participation
by the public; and (3) periodic program evaluations of the impacts of VOC
HAP trades on the health and environment of local communities.
c.
MCAQD proposes to correct this deficiency by adding Section 402 to the
rule which states: “Nothing herein restricts independent enforcement
authorities under the Clean Air Act by other parties.”
d.
MCAQD will correct this deficiency by revising the rule to allow the
Department to obtain from the participating sources all information
necessary to calculate each permitted generator and credit user’s
emissions (tonnage). MCAQD is proposing to require information be
provided by the generator in the application under Section 301.1, including
historic vehicle miles traveled, in order to be able to calculate source
emissions. MCAQD may use this information along with MOVES
generation of an emissions factor, which is proposed to be determined in
Appendix A, to calculate a source’s qualifying emission reductions. A
description of how this information will be provided to the public will be
included in the EIP support document.
Comment 18 
Measuring and Tracking Results: The EIP must include procedures to measure and 
track results. We believe many of these provisions can be provided as a narrative in the 
EIP support document. Any provisions that must be included in the Rule 205 text are 
noted below. See Section 5.3 of the Federal EIP Guidance for additional information. 
a.
The Department’s EIP support document must discuss how the
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 25 of 125

Department will ensure that the MERCs granted remain surplus to all other 
CAA requirements (e.g., have not been relied upon in other required CAA 
demonstrations) and how these MERCs may affect the air quality planning 
emissions inventories and transportation conformity. 
b.
The Department’s EIP support document must discuss the relationship
between the Department and Maricopa Association of Governments
(MAG) in ensuring this program will comply with applicable CAA planning
requirements, particularly concerning development of the required
attainment plan and ongoing transportation conformity determinations.
c.
The Department’s EIP support document must also contain provisions to
make public all information regarding issued MERCs. At a minimum, you
must maintain a record (often referred to as a Banking Register) for each
MERC issued pursuant to Rule 205. This MERC Register would contain the
information listed above in Comment 3. See Section 6.5(d) of the Federal
EIP Guidance for additional information.
d.
The Department’s EIP support document must include specific program
evaluation procedures for the EIP. The Department is responsible for
submitting a review of the EIP to EPA Region 9 every 3 years to determine
its success and to address any identified deficiencies.
Remedy 18 
MCAQD will correct the corresponding deficiencies outlined in the EPA’s March 25, 
2024 letter as follows: 
a.
MCAQD will correct this deficiency by including in the EIP support
document a discussion of how the Department will ensure that the MERCs
granted remain surplus to all other CAA requirements and how these
MERCs may affect the air quality planning emissions inventories and
transportation conformity.
b.
MCAQD will correct this deficiency by including in the EIP support
document a discussion of the relationship between MCAQD and Maricopa
Association of Governments (MAG) in ensuring the EIP will comply with
applicable CAA planning requirements.
c.
MCAQD will correct this deficiency by making clear in the EIP support
document that the public has access to all information regarding issued
MERCs. The Department will, at a minimum, maintain a record for each
MERC issued pursuant to Rule 205. Such records will contain the
information identified in commitment 3 above.
d.
MCAQD will correct this deficiency by providing in the EIP support
document specific procedures for program evaluation of the EIP and
submission of an EIP review to EPA Region 9 every three years.
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 26 of 125

Comment 19 
Enforcement Elements for EIPs: The Department’s EIP must include the following 
enforcement provisions. We believe many of these provisions can be provided as a 
narrative in the EIP support document. Because emission trading programs involve 
more than one party, the EIP support document must include provisions for identifying 
and assessing enforcement liability. Rule 205 currently refers to these parties as the 
“permitted generator” and the “user.” See Section 6.1 of the Federal EIP Guidance for 
additional information. 
a.
The permitted generator must be liable for the truth and accuracy of the
information provided in their application requesting the issuance of
MERCs and in their monthly and annual recordkeeping and reporting
requirements.
b.
The permitted generator must be liable for any shortfalls in achieving, on a
12-month rolling basis, the emission reductions for which the ERC
certificate was granted.
c.
The user must be liable for any emission increases that are not fully offset
based on a 12-month rolling comparison of the quantity of emission
reductions achieved by the permitted generator and the amount of actual
emissions emitted by the user for that particular project.
Remedy 19 
 MCAQD will correct this deficiency by including in the EIP support document provisions 
specifying the following: (a) the permitted generator must be liable for the truth and 
accuracy of the information provided in their application requesting the issuance of 
MERCs and in their monthly and annual recordkeeping and reporting requirements, (b) 
the permitted generator must be liable for any shortfalls in achieving, on a 12-month 
rolling basis, the emission reductions for which the ERC certificate was granted, and (c) 
the user must be liable for any emission increases that are not fully offset based on a 
12-month rolling comparison of the quantity of emission reductions achieved by the 
permitted generator and the amount of actual emissions emitted by the user for that 
particular project. 
The Rule 205 EIP support document will be available for review 30 days before the 
public hearing which is currently anticipated to be May 21, 2025. 
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 (A.R.S. § 49-471.05(5)).
U.S. Environmental Protection Agency Region 9 (2024). Technical Support Document
for EPA’s Notice of Proposed Rulemaking on Revision to the Arizona State 
Implementation Plan Regarding Rule 205, “Emission Offsets Generated by Voluntary 
Mobile Source Emission Reduction Credits”, 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 27 of 125

https://www.regulations.gov/document/EPA-R09-OAR-2024-0311-0007 
U.S. Environmental Protection Agency, “Improving Air Quality with Economic Incentive 
Programs” January 2001, 
https://www.regulations.gov/document/EPA-R09-OAR-2024-0311-0009 
6.
An economic, small business and consumer impact statement (A.R.S. § 49-
471.05(6)):
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 (A.R.S. §
41-1055(A)(1)):
This rulemaking is proposing to revise Rule 205 so that it can be approved into the
Arizona SIP and it can be utilized to generate MERCs.
(a) The conduct and its frequency of occurrence that the rule is designed to change
(A.R.S. § 41-1055(A)(1)(a)). 
MCAQD is proposing to revise Rule 205 to remedy deficiencies identified by the EPA 
and to address stakeholder comments regarding the practicality and usability of the 
rule. 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 (A.R.S. § 41-
1055(A)(1)(b)). 
MCAQD is proposing to revise Rule 205 to remedy deficiencies identified by the EPA 
and to address stakeholder comments regarding the practicality and usability of the 
rule. Currently, there is a limited amount of VOC and NOx credits available in 
Maricopa County. The lack of available credits adversely impacts Maricopa County’s 
economy by limiting the ability of certain major stationary sources to locate or 
expand operations within Maricopa County. If Rule 205 is not revised and approved 
into the Arizona SIP, the ability for certain major stationary sources to locate or 
expand in Maricopa County will continue to be limited. 
(c) The estimated change in frequency of the targeted conduct expected from the rule 
change (A.R.S. § 41-1055(A)(1)(c)). 
MCAQD is proposing to revise Rule 205 to remedy deficiencies identified by the EPA 
and to address stakeholder comments regarding the practicality and usability of the 
rule. The revisions are explained in more detail in Item #4 of this notice. 
A brief summary of the information included in the economic, small business and 
consumer impact statement (A.R.S. § 41-1055(A)(2)). 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 28 of 125

Participation in the generation, certification, and utilization of MERCs is voluntary; 
however, the generation, certification, and utilization of MERCs from captive fleet 
vehicles must be done in compliance with the applicable provisions of Rule 205. 
This rulemaking and approval of this rule into the Arizona SIP is anticipated to have an 
overall positive impact on Maricopa County’s economy. The facilitation, generation, and 
certification of MERCs will allow more businesses wishing to construct new major 
sources or make major modifications to existing major sources in Maricopa County to 
meet the emission offset requirement of the CAA. In addition, the owner or operator of a 
captive fleet of vehicles that generates and certifies MERCs will benefit by being able to 
sell MERCs to the large businesses needing them for emissions offsets. 
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 (A.R.S. § 41-1055(A)(3)). 
Name: 
Will Adrian or Kimberly Butler 
Maricopa County Air Quality Department 
Planning and Analysis Division 
Address: 
301 W. Jefferson St., Suite 410 
Phoenix, AZ 85003 
Telephone: 
602-506-6010 
Fax: 
602-506-6179 
Email: 
AQPlanning@maricopa.gov 
Online: 
Submit a Comment 
An identification of the persons who will be directly affected by, bear the costs of or 
directly benefit from the proposed rulemaking (A.R.S. § 41-1055(B)(2)). 
Participation in the generation, certification, and utilization of MERCs is voluntary; 
however, the generation, certification, and utilization of MERCs from captive fleet 
vehicles must be done in compliance with the applicable provisions of Rule 205. Both 
the generator and the credit user of the MERCs will bear the costs and benefits from the 
proposed revisions. 
The owner or operator of a captive fleet of vehicles that chooses to replace or retrofit 
captive fleet vehicles to reduce or eliminate emissions and generate MERCs will bear 
the costs associated with the cost to replace or retrofit the captive fleet vehicles; 
however, they will benefit from the ability to generate MERCs and, ultimately, sell the 
certified MERCs for a profit. 
The owner or operator of a major stationary source needing emission offsets will bear 
the cost of purchasing the certified MERCs but will benefit from the ability to construct 
a new major stationary source in Maricopa County or make a major modification to an 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 29 of 125

existing major stationary source in Maricopa County. 
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 (A.R.S. § 41-1055(B)(3)(a)). 
The cost incurred by MCAQD to review MERC applications and certify MERCs are 
currently accounted for under the locally adopted version of Rule 205, § 401 Fees. 
MCAQD proposes to account for cost incurred by MCAQD to review ERC 
applications and certify ERCs moving forward through Rule 203 (Emission Reduction 
Credit (ERC) General Requirements) which was adopted on December 11, 2024.  
The cost incurred by MCAQD to inspect and verify compliance of the generator with 
Rule 205 has been accounted for by permitting costs incurred through § 301.2 
Action on the Application of this rule and Rule 280 (Fees), which must be provided 
by the generator to ensure the permanency and enforceability of the certified 
MERCs.  
The cost to the Arizona Department of Environmental Quality (ADEQ) of 
administering the Arizona Emissions Bank has been, and is expected to continue to 
be, minimal as stated in ADEQ’s Notice of Final Rulemaking (25 A.A.R. 1433, June 
14, 2019). 
(b) The probable costs and benefits to a political subdivision of this state directly 
affected by the implementation and enforcement of the proposed rulemaking 
(A.R.S. § 41-1055(B)(3)(b)). 
Participation in the generation, certification, and utilization of MERCs is voluntary. 
Nevertheless, in the event a political subdivision such as the City of Phoenix elects 
to become a generator they will bear the costs associated with the cost to replace or 
retrofit the captive fleet vehicles. Additionally, the political subdivision who is an 
owner or operator of a captive fleet of vehicles that chooses to replace or retrofit 
captive fleet vehicles to reduce or eliminate emissions and generate MERCs will 
bear the costs associated with ERC application processing and obtaining a new 
permit or permit revision to impose conditions to make reductions in qualifying 
emissions permanent and enforceable. However, the political subdivision who is an 
owner or operator of a captive fleet of vehicles will benefit from the ability to 
generate MERCs and sell the certified MERCs for a profit, which MCAQD expects will 
sufficiently offset the aforementioned costs. 
(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 (A.R.S. § 
41-1055(B)(3)(c)). 
Participation in the generation, certification, and utilization of MERCs is voluntary; 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 30 of 125

however, the generation, certification, and utilization of MERCs from captive fleet 
vehicles must be done in compliance with the applicable provisions of Rule 205. 
Both the generator and the credit user of the MERCs will bear the costs and benefits 
from the proposed rulemaking. 
The owner or operator of a captive fleet of vehicles that chooses to replace or 
retrofit captive fleet vehicles to reduce or eliminate emissions and generate MERCs 
will bear the costs associated with the cost to replace or retrofit the captive fleet 
vehicles. Additionally, the owner or operator of a captive fleet of vehicles that 
chooses to replace or retrofit captive fleet vehicles to reduce or eliminate emissions 
and generate MERCs will bear the costs associated with ERC application processing 
and obtaining a new permit or permit revision to impose conditions to make 
reductions in qualifying emissions permanent and enforceable. However, the owner 
or operator of a captive fleet of vehicles will benefit from the ability to generate 
MERCs and sell the certified MERCs for a profit, which MCAQD expects will 
sufficiently offset the aforementioned costs. 
The owner or operator of a major stationary source needing emission offsets will 
bear the cost of purchasing the certified MERCs but will benefit from the ability to 
construct a new major stationary source in Maricopa County or make a major 
modification to an existing major stationary source in Maricopa County. 
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 (A.R.S. § 41-1055(B)(4)). 
The probable impact on private and public employment in businesses directly affected 
by the proposed rulemaking is expected to be positive. The generation of more MERCs 
will allow more businesses to locate and expand in Maricopa County, thereby increasing 
the overall economic growth and expansion. 
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 
(A.R.S. § 41-1055(B)(5)(a)). 
Participation in the generation, certification, and utilization of MERCs is voluntary; 
however, the generation, certification, and utilization of MERCs from captive fleet 
vehicles must be done in compliance with the applicable provisions of Rule 205. 
The small businesses subject to Rule 205 are the owners or operators of captive 
fleet vehicles that choose to reduce or eliminate emissions from gasoline and 
diesel-powered fleet vehicles. 
(b) The administrative and other costs required for compliance with the proposed 
rulemaking (A.R.S. § 41-1055(B)(5)(b)). 
Participation in the generation, certification, and utilization of MERCs is voluntary; 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 31 of 125

however, the generation, certification, and utilization of MERCs from captive fleet 
vehicles must be done in compliance with the applicable provisions of Rule 205. 
Administrative Costs: Small business choosing to generate and certify MERCs must 
comply with the application and recordkeeping requirements of the rule. 
Other Costs: Small business choosing to generate and certify MERCs will bear costs 
associated with the cost to replace or retrofit captive fleet vehicles and the cost of 
any monitoring equipment required by the rule to ensure the continued generation of 
MERCs. 
(c) A description of the methods that the agency may use to reduce the impact on 
small businesses (A.R.S. § 41-1055(B)(5)(c)). 
MCAQD has a business assistance (BA) program that provides administrative and 
technical assistance to business owners related to air quality rules and regulations. 
Courtesy site visits, on-site training, rule interpretation, and compliance assistance 
are offered to small businesses at no charge. 
i.
Establish less stringent compliance or reporting requirements in the rule for
small businesses (A.R.S. § 41-1035(1)).
Participation in the generation, certification, and utilization of MERCs is voluntary;
however, the generation, certification, and utilization of MERCs from captive fleet
vehicles must be done in compliance with the applicable provisions of Rule 205.
MCAQD is not aware of any less stringent compliance or reporting requirements.
ii. Establish less stringent schedules or deadlines in the rule for compliance or
reporting requirements for small businesses (A.R.S. § 41-1035(2)).
Participation in the generation, certification, and utilization of MERCs is voluntary;
however, the generation, certification, and utilization of MERCs from captive fleet
vehicles must be done in compliance with the applicable provisions of Rule 205.
MCAQD is not aware of any less stringent schedules or deadlines for compliance
or reporting requirements.
iii. Consolidate or simplify the rule's compliance or reporting requirements for
small businesses (A.R.S. § 41-1035(3)).
Participation in the generation, certification, and utilization of MERCs is voluntary;
however, the generation, certification, and utilization of MERCs from captive fleet
vehicles must be done in compliance with the applicable provisions of Rule 205.
MCAQD is not aware of any way to consolidate or simplify the rule’s compliance
or reporting requirements, but MCAQD provides the Business Assistance
Program to provide information and technical assistance for permit holders
including the small business community.
iv. Establish performance standards for small businesses to replace design or
operational standards in the rule (A.R.S. § 41-1035(4)).
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 32 of 125

Participation in the generation, certification, and utilization of MERCs is voluntary; 
however, the generation, certification, and utilization of MERCs from captive fleet 
vehicles must be done in compliance with the applicable provisions of Rule 205. 
v. Exempt small businesses from any or all requirements of the rule (A.R.S. § 41-
1035(5)).
Participation in the generation, certification, and utilization of MERCs is and will
remain voluntary.
(d) The probable cost and benefit to private persons and consumers who are directly 
affected by the proposed rulemaking (A.R.S. § 41-1055(B)(5)(d)). 
This rulemaking will not impose any costs to private persons or consumers. The 
citizens and visitors to Maricopa County will benefit through the reduction of air 
pollutants and economic growth. 
A statement of the probable effect on state revenues (A.R.S. § 41-1055(B)(6)). 
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 nonselected 
alternatives (A.R.S. § 41-1055(B)(7)). 
MCAQD is not aware of any less intrusive or costly methods to achieve the purpose of 
this rulemaking. 
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 (A.R.S. § 41-1055(B)(8)). 
Not applicable. 
7.
The proposed effective date of the rule (A.R.S. § 49-471.05(7)):
The proposed effective date of this rulemaking is May 21, 2025.
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 (A.R.S. § 49-471.05(8)):
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
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 33 of 125

§ 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. 
MCAQD is in compliance with A.R.S. §§ 49-112(A) and (B). The proposed rule revision 
does not increase stringency of requirements as the rule itself is voluntary for the 
generation of mobile source emission reduction credits. Additionally, the Director of the 
Arizona Department of Environmental Quality (ADEQ) has not adopted a mobile source 
emission reduction credit rule under the state’s regulations with which to compare the 
proposed rule revisions of Rule 205. 
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(B):
(a) List of all previous notices posted to the Maricopa County EROP website 
addressing the proposed rule: 
Notice 
 
 
 
 
 
 
Date of Posting 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 34 of 125

Briefing Notification to County Manager:  
 
November 22, 2021 
Notices of Stakeholder Workshop:  
 
 
December 22, 2021 
October 18, 2022 
Notice of Board of Health Meeting: 
Notice of Proposed Rulemaking:   
Notice of Board of Health Meeting:  
Notice of Public Hearing:   
Briefing Notification to County Manager: 
Email Notification to Board of Health: 
Notice of Stakeholder Workshop:  
Notice of Proposed Rulemaking:   
January 10, 2022 
December 7, 2022 
January 9, 2023 
March 15, 2023 
April 9, 2024 
September 3, 2024 
September 3, 2024 
February 26, 2025 
(b) The following discussion addresses each of the elements required for a 
concise explanatory statement, as prescribed by A.R.S. § 49-471.07(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.
No changes were made after the Second Notice of Proposed Rulemaking was
published on February 26, 2025.
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 Second Notice of Proposed Rulemaking. MCAQD received
written comments from two stakeholders. All of the comments were reviewed
and evaluated by MCAQD. A link to a copy of the stakeholder comments is
provided.
Stakeholder #1: Comments #1 through #2 submitted on July 17, 2024.
Comment #1: 
Given that part of the calculation description, it is going to be
difficult to generate credits and in my opinion Rule 205 is internally
inconsistent.
Return to list of attachments
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 35 of 125

First, the definition of baseline emissions at 203 is: 
BASELINE EMISSIONS: The average rate at which a baseline vehicle would 
have actually emitted the pollutant in absence of generating emission 
reductions during the two preceding calendars years, or two calendar years 
more representative of normal emissions within the 5-year period 
immediately before the reduction in qualifying emissions. 
Which can be compared to the text that you highlighted from Appendix A. 
Baseline vehicle engine model year corresponds to the calendar year in which 
the emission reductions are generated by replacing or retrofitting the baseline 
vehicle. 
Changing the model year of the baseline vehicle from what it actually is 
(which is what defines what the vehicle would have “actually emitted”), to the 
current calendar year is not what we did for WM originally and would have 
precluded the generation of any significant MERCS. 
Response #1: 
MCAQD revised the definition of “Baseline Emissions” to 
include the original vehicle as follows:  
“The emissions an original vehicle has actually emitted, as determined in 
Appendix A, § A.” 
In addition, the “Baseline Pollutant Emissions Factor” under Appendix A was 
revised to include the “original vehicle engine model year” as an input under 
Appendix A, § A 3.(b). 
Comment #2: 
Another internal inconsistency can be found in the definition 
of replacement vehicle at 207: 
207:  REPLACEMENT VEHICLE: Vehicle used to generate certified credits that 
is certified to an emission limit less than the baseline vehicle it replaces and 
is in compliance with the most recent applicable federal emission standard at 
the time of replacement. 
If you have to use the same model year for the baseline and replacement 
vehicle, it’s generally going to be impossible to generate credits. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 36 of 125

What I think Appendix A should have said is:  Baseline vehicle engine 
emissions are to be estimated based on the vehicle’s actual model year in the 
corresponds to the calendar year in which the emission reductions are 
generated by replacing or retrofitting the baseline vehicle. 
This is what was done for WM’s NG vehicles for both the baseline and the 
new vehicles. 
Response #2: 
MCAQD revised the definition of “Baseline Emissions” to 
include the original vehicle so the “baseline emissions” and “replacement 
vehicle” do not both reference the same model year. 
 The definition reads as follows: “The emissions an original vehicle has 
actually emitted, as determined in Appendix A, § A.” 
In addition, the “Baseline Pollutant Emissions Factor” under Appendix A was 
revised to include the “original vehicle engine model year” as an input under 
Appendix A, § A 3.(b). 
Stakeholder #1: Comments #3 through #6 submitted on September 26, 2024. 
Comment #3: 
Intel is disappointed that there is not a Clean Diesel option to 
create MERCs in Rule 205.  A new Clean Diesel engine can match the NOx 
reductions that CNG-powered engine can achieve (per MOVES). 
Response #3: 
Clean diesel is not restricted from generating credits in the 
provisions of the rule. 
Comment #4: 
Intel has a hard time understanding the intent of having a 
VMT requirement.   If the Fleet owner of the associated MERCs does not 
change out vehicles with equal or cleaning burning engines they could end up 
taking joy rides around Phoenix just to meet their VMT requirement and this 
will actually result in higher emissions. Using that same logic the MERC buyer 
should get a higher amount of MERCs in years where the Fleet goes over its 
VMT requirement. 
Response #4: 
The intent of the VMT requirement is to ensure the activity 
level of the replacement vehicles remains the same, or close to the same, as 
the vehicles they replaced. This, in turn, ensures no load shifting occurs and 
the integrity of the MERCs continues. MCAQD added a definition of load 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 37 of 125

shifting which reads as follows: “Shifting of activity, measured in VMT, of a 
replaced or retrofitted vehicle for which a MERC certificate has been issued to 
a higher emitting vehicle.” MCAQD understands a generator may travel less 
miles than the VMT amount documented on the MERC certificate for a variety 
of reasons (i.e. more efficient routes, cancelled contracts, etc.). As such, 
MCAQD revised the rule to include a “Demonstration of Continued 
Compliance”, whereby a generator provides a demonstration to the Control 
Officer for approval to show that the lower VMT was not a result of load 
shifting and the integrity of the MERCs continue. If the demonstration is 
approved, then no further action is required. In the event load shifting has 
occurred, then further action must be taken to make up for a shortfall in 
emission reductions. 
Comment #5: 
Would of preferred off-road vehicles be in 205 ([Personal 
Name] also feels that way) but I get the timing element of why it isn’t. 
Response #5: 
Rule 205 originally allowed for the generation of qualifying 
emission reductions from off-road vehicles; however, EPA determined the rule 
did not contain adequate provisions to allow for it. The EPA requested the 
term “off-road” be removed from the rule and MCAQD removed it. EPA 
suggested in its Technical Support Document (TSD) incorporating off-road 
credit provisions in a separate EIP rule. MCAQD is currently revising Rule 204 
(Emission Reduction Credit (ERC) Generation, Certification, and Use) to 
incorporate provisions allowing for the generation, certification, and use of 
ERCs from off-road vehicles. 
Comment #6: 
The other item I forgot about is it clear that the buyer of the 
credits only needs to produce extra credits if it is using 100% of its NOx limit. 
Response #6: 
MCAQD revised the rule under Section 401.3 b.(2), allowing 
the credit user or generator to submit an action plan to the Control Officer for 
approval if the emission reduction shortfall (ERS) is less than 10% of the total 
MERCs issued by the Department. This action plan may include 
documentation demonstrating the credit user’s actual emissions for the 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 38 of 125

specific NSR permit issuance that relied on MERCs are still sufficiently offset 
despite the VMT shortfall. 
Stakeholder #2: Comments #7 through #22 submitted on September 26, 2024. 
Comment #7: 
The proposed Appendix A, calculations for determining the 
credits, uses the actual model year for the baseline vehicles emissions which 
will likely increase the credits compared to the approach used in our 2021 
project. This is favorable. 
Response #7: 
MCAQD appreciates your support for the rule revision. 
Comment #8: 
The compliance of point for our current MERC program is 
based upon vehicle replacement and not on the mileage.  The Proposed Rule 
will change that as it requires as 12-mn VMT rolling calculation and if there is 
an emissions short fall then the credit generator and user must take prompt 
action to report, plan to resolve the short fall and if delays occur in resolving 
the shortfall the user may face permit modifications and/or compliance 
issues. Currently, the agreed upon methodology requires an annual evaluation 
of the mileage and calculation of the emission reduction.  Increasing to 
monthly is time consuming and adding the compliance steps will be complex. 
Response #8: 
WMAZ’s ERC permit conditions contained within the SIP and 
the currently adopted version of Rule 205 both require monthly VMT (or hours 
of operation as an alternative in the permit conditions) to be tracked and 
recorded. As such, the proposed 12 month rolling total of VMT is not 
considered to be significantly more time consuming or burdensome. 
Additionally, MCAQD revised the rule requirements regarding VMT shortfalls 
providing the generator and credit user more flexibility to address VMT 
shortfalls. 
Comment #9: 
The 200 mile removal requirement from the Non-Attainment 
Area excludes cities like Tucson and Flagstaff which will likely be is too 
restrictive.  At times WMAZ moves trucks from Phoenix to these areas.   
Other fleets may wish to do the same. This may limit participation in this 
voluntary rule. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 39 of 125

Response #9: 
The requirement to remove the original vehicle more than 
200 miles outside the nonattainment area is included in the currently adopted 
version of Rule 205 and is not a proposed revision under this rulemaking. 
Additionally, this requirement ensures the original vehicle does not return to 
the nonattainment area and interfere with Maricopa County's progress 
towards attainment as is required by the CAA. 
Comment #10: 218 - add in “….any other adjustments (e.g. for load 
factors)…” after “…MOVES output emissions factors.” 
Response #10: As EPA states in its TSD, "a MERC generating rule must 
include specific methodologies for calculating emissions, describing what is 
to be measured and how, and how the measurements are to be documented 
and reported. The calculation methodology must also be specific." The 
suggested addition is not specific enough for rule approvability, however 
Section 302.1 d. does allow for the submission of an alternative calculation 
methodology which could include adjustments such as load factor. 
Comment #11: 219 – add a definition for “Ratio Adjusted Emission Factor” 
found in 401.3,a(2). 
Response #11: The term “Ratio Adjusted Emission Factor” was removed 
from the draft rule. 
Comment #12: 222 – add a clarification that the federal engine 
manufacturer emission standards are not applicable requirements for fleet 
operators. 
Response #12: As proposed in Section 302.2 d., the generator must 
subsequently replace replacement or retrofit vehicles with vehicles certified 
to the same, or lower, EPA emission standard. This is to ensure permanence 
of the emission reductions so that a higher emitting vehicle does not 
invalidate the qualifying emission reductions. The rule does not state that a 
generator must comply with a federal mobile source emission standard, only 
that they must continue to operate a vehicle with an equal or lower emission 
rate to ensure the validity of the issued MERCs. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 40 of 125

Comment #13: 301.2(c) – Please add text to clarify that our current process 
of amending vehicle lists as a administrative revision is not a modification 
requiring public participation and the revision steps in Section 407 of Rule 
220. 
Response #13: Amendment of a vehicle list would require documentation in 
a compliance report but not a permit revision as the permit language would 
not need to be revised, and this amendment would not require public notice.  
Comment #14: 301.2(d)1(c) & 302.2(f) - Note that future completion dates 
for the replacement of vehicles are difficult to predict thus there needs to be 
some flexibility and leniency.  When a permit is used for MERC enforcement, 
and if the completion date is in the permit is not met, it would be a permit 
violation.  Often times these delays are outside of control of permitee.  We 
recommend that a permit notification be allowed to modify this date, 
obviously coordinated with the MERC user to ensure that their start up needs 
are met. 
Response #14: Future completion date for implementation of replacement 
or retrofit vehicles is incorporated into the proposed rule. This is the intent of 
Section 301.3 b., whereby a MERC certificate and associated permit or permit 
revision include a future implementation date. A delay as described in the 
comment, could be addressed through an application for Non-Title V permit 
modification described in Rule 220, Section 400. When determining a future 
completion date, the generator should evaluate all potential implementation 
obstacles for an appropriate date. Additionally, it is important to note the 
credit user cannot commence operation of their permitted new source or 
modification until the generator has completed implementation of the 
qualifying emission reductions for which a MERC certificate was issued. In 
other words, a delay in the completion date will lead to a delay in 
commencement of operations for the credit user. 
Comment #15: 302.2(b)(3) & (4) – need to be removed.  If the current 
version of GPS system and software is tracking vehicles then there is no 
reason to spend funds on a new system.  System changes will have 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 41 of 125

unintended impacts across related GIS fleet systems, such as requiring 
equipment change outs conflicts with many other operation systems on the 
trucks.  Additionally, we operate with the same GPS system nationally.  The 
potential impact of this makes this an unreasonable request. Additionally, this 
is also more stringent that our current permit. 
Response #15: MCAQD revised Section 302.2 b. so that the fleet 
management system must be updated in accordance with manufacturer’s 
written instructions. This is intended to implement reasonable requirements 
for basic updating and maintenance of a location tracking system and 
software. 
Comment #16: 302.2(b)(c) – Using 200 miles means in all 4 directions of 
the edge of Nonattainment Area trucks could not be relocated in a 
metropolitan area in Arizona.  The closest potential metropolitan areas would 
be in El Centro, CA, Las Vegas, NV, Farmington or Albuquerque, NM or in the 
county of Mexico.  Basically, this prohibits areas like Tucson & Flagstaff 
which are in attainment. This may hurt the viability of the rule as it would rule 
out firms that may want to participate but cannot be due to distance logistics 
or financial impact.  WMAZ proposes language that gives the generator the 
option of performing a demonstration or air modeling to show that original 
fleet vehicle operating closer will have no impact to the Maricopa non-
attainment area.  This is also more stringent that our current permit, and we 
have already moved units to Tucson as an example. 
Response #16: The requirement to relocate the original vehicle more than 
200 miles outside the Maricopa County ozone nonattainment area helps 
ensure the permanence of the qualifying emission reductions, which is 
required under 40 CFR 51.165 for federal NSR offsets and in the current 
locally adopted rule version. The requirements of the rule will be applicable to 
certification of projects after rule adoption. 
Comment #17: 302.2(d) -  The statement “The permitted generator shall 
further ensure that any replaced baseline vehicle that is subsequently 
replaced again, is not operated in any other captive fleet owned or operated 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 42 of 125

by the permitted generator in the applicable Maricopa County nonattainment 
area”  should be removed as this is confusing, and any subsequent 
replacement would meet the low emissions rate approved in the MERC. 
Response #17: MCAQD removed the language from the draft rule. 
Comment #18: 401.2 - 12-month rolling VMT -  a. Our current MERC program 
with Maricopa County is based upon vehicle/engine replacement and not on 
the mileage, and currently, the agreed upon methodology requires an annual 
evaluation of the mileage.  Increasing that to monthly is time consuming and 
complex.  Certainty if the mileage matches the application that is preferable, 
but it should not be point of compliance.  This is a reasonable approach that 
will  make the program viable.  b. WM has spare trucks to replace out of 
service trucks and has a stable business within the non-attainment area; 
however, many companies may not have extras units readily available thus 
this requirement will likely be limiting the viability of ERC program. c.  
Moreover, if there are lower miles, the objective of lowering emissions is met, 
as CNG is 1/10th emissions of diesel, and participants in this voluntary 
program should not face compliance issues.  d) Currently we are assessing 
the VMT and the emissions reductions on an annual basis which provides 
time for the fleets to assessment, make repairs or order replacements. e) 
Additionally, the VMT isn’t proportional to the overall emissions, as each 
vehicle will have a different emission factor, and then subsequent 
replacements will likely differ again.  Therefore, a reduction in VMT doesn’t 
easily equate to a negative shortfall. 
Response #18: WMAZ’s ERC permit conditions contained within the SIP and 
the currently adopted version of Rule 205 both require monthly VMT (or hours 
of operation as an alternative in the permit conditions) to be tracked and 
recorded. As such, the proposed 12 month rolling total of VMT is not 
considered to be significantly more time consuming or burdensome.  
Regarding spare trucks, if a lower emitting vehicle is not available for a 
subsequent vehicle replacement to ensure emission reductions continue, 
then the MERCs may no longer be valid and the credit user may be required to 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 43 of 125

take some action to address the VMT shortfall. A business should be 
prepared to address the vehicle replacement requirement as part of their 
participation in the program.  
In order to address the generator operating at a lower VMT, MCAQD revised 
the rule to include a “Demonstration of Continued Compliance” whereby a 
generator provides a demonstration to the Control Officer for approval within 
30 days of VMT shortfall discovery to show that the lower VMT was not a 
result of load shifting and the integrity of the MERCs continue. If the 
demonstration is approved, then no further action is required. In the event 
load shifting has occurred, then further action must be taken to make up for a 
shortfall in emission reductions. Load shifting is defined as follows: “Shifting 
of activity, measured in VMT, of a replaced or retrofitted vehicle for which a 
MERC certificate has been issued to a higher emitting vehicle.” 
In addition, MCAQD agrees there is not a direct correlation between VMT and 
emissions. Section 401.3 requires the credit user to calculate the Emission 
Reduction Shortfall (ERS) by subtracting the VMT achieved, as reported by the 
credit generator pursuant to § 401.2 a.(2), from the VMT required in the MERC 
certificate, and multiply the difference by the applicable qualifying Emission 
Reduction Emission Factor (EREF) specified in the MERC certificate. In this 
way, emission reduction shortfall is evaluated using actual vehicle engine 
emission factors in addition to VMT. 
Comment #19: 401.3 Credit User VMT – Note that the credit user will may 
have difficulty complying:   1) As an example, if WM provides Intel VMT short 
fall how would you calculate the emissions reduction from the short fall with 
just the VMT? 2) in (3) 10 days to develop a plan and the 3 months to resolve 
is not adequate time; if part of the solution is adding an extra vehicle that 
could take 9 months for the fleet owner. 3) requirement (4) requires a permit 
mod within 90 days to reduce emissions.  This seems un-reasonable for a 
large and complex facility. Then in (5) missing these steps would be violation. 
Response #19: MCAQD revised the rule requirements regarding VMT 
shortfalls providing the generator and credit user more flexibility to address 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 44 of 125

VMT shortfalls. For example, Section 401.2 a.(2)(b)(i) allows the generator to 
provide a demonstration to the Control Officer to show that the lower VMT 
was not a result of load shifting and the integrity of the MERCs continues. If 
the demonstration is approved by the Control Officer, then no further action is 
required by either the generator or credit user. If the generator cannot provide 
such a demonstration, then the generator must notify the credit user of the 
VMT shortfall so the credit user can conduct a VMT shortfall evaluation.  
Comment #20: 504.3 – revise “current vehicle mileage” to “monthly vehicle 
mileage”. 
Response #20: “Current” vehicle milage is accurate for maintenance 
purposes and provides additional verification of actual VMT accrued. 
Comment #21: 505.3 – “the 10th of the month”, should be “10th day of the 
VMT calculation”. 
Response #21: “VMT Calculation” is not defined within the rule, and may add 
more complexity and confusion. Additionally, the compliance demonstration 
timeframe was changed to within 30 days of the end of the month. 
Comment #22: App. A, A,3 – 1) using the latest version of MOVES could 
create a difference from the MOVES used for a approved MERC application.  
Thus, we recommending using version of the MOVES from the MERC 
application. 
Response #22: EPA's Rule 205 TSD requires latest MOVES version at time of 
issuance, "The MOVES model is a key resource for both the ozone attainment 
plan and quantifying emission reductions. Therefore, Rule 205 must require 
that the latest version of MOVES be used when evaluating qualifying emission 
reductions for MERC issuance." 
Exact Wording of the Rule 
Note to reader:  Two versions of the rule are included below. The first version is a strikethrough/underline 
version showing the intended actions to make new sections or amend, repeal, or renumber the sections of 
the rule. The second version is a clean version without the strikethrough/underline included for readability 
purposes.
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 45 of 125

MARICOPA COUNTY AIR POLLUTION CONTROL REGULATIONS 
REGULATION II – PERMITS AND FEES 
RULE 205 (EMISSION OFFSETS GENERATED BY VOLUNTARY 
MOBILE SOURCE EMISSION REDUCTION CREDITSREDUCTIONS) 
INDEX 
SECTION 100 – GENERAL 
101 
PURPOSE 
102 
APPLICABILITY 
SECTION 200 – DEFINITIONS 
201 
ACCOUNT HOLDERBASE YEAR EMISSION INVENTORY 
202 
ARIZONA EMISSIONS BANK 
203 
BASELINE EMISSIONS 
204 
BASELINE VEHICLE 
205 
203 
CAPTIVE FLEET 
206 
204 
CERTIFIED EMISSION REDUCTION CREDIT USER 
207 
205 
EMISSION REDUCTION CREDIT (ERC) or CREDIT 
208 
206 
ENFORCEABLE 
209 
207 
FLEET MANAGEMENT SYSTEM 
208 
GENERATOR 
209 
HISTORIC VEHICLE MILES TRAVELED (HVMT) 
210 
LOAD SHIFTING 
211 
MERC CERTIFICATE 
212 
MOBILE SOURCE EMISSION REDUCTION CREDIT (MERC) 
210 
213 
MOVES 
Strikethrough/underline version
Return to list of attachments
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 46 of 125

214 
NONATTAINMENT AREA 
215 
OFFSETS 
211 
PERIODIC EMISSIONS INVENTORY 
212 
216 
ORIGINAL VEHICLE 
217 
PERMANENT 
213 
PERMITTED GENERATOR 
214 
218 
QUALIFYING EMISSIONS 
215 
219 
QUANTIFIABLE 
216 
220 
REAL 
217 
221 
REPLACEMENT OR REPLACED VEHICLE 
218 
222 
RETROFIT OR RETROFITTED VEHICLE 
219 
223 
SURPLUS 
224 
VEHICLE SOURCE TYPE 
SECTION 300 – STANDARDS 
301 
CERTIFICATION OF CREDITS FOR MOBILE SOURCEQUALIFIED EMISSION 
REDUCTIONS BY A PERMITTED GENERATOR 
302 
MERC GENERATION 
303 
REGISTRATION OF CERTIFIED CREDITS IN THE ARIZONA EMISSIONS BANK 
303 
USE OF THE CERTIFIED CREDITSMERC CERTIFICATES 
SECTION 400 – ADMINISTRATIVE REQUIREMENTS 
401 
FEES 
401 
OFFSET INTEGRITY RESPONSIBILITIES 
402 
ENFORCEMENT AUTHORITY 
SECTION 500 – MONITORING AND RECORDS 
501 
RECORDKEEPING AND RECORDS RETENTION 
502 
INSPECTIONS 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 47 of 125

503 
MERC GENERATION MONITORING 
504 
MERC GENERATION RECORDS 
505 
COMPLIANCE DEMONSTRATION 
APPENDIX TO RULE 205 
APPENDIX A: – CALCULATIONS FOR DETERMINING EMISSION REDUCTIONS FROM 
EACH VEHICLE REPLACEMENT OR RETROFIT PROJECTS 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 48 of 125

Adopted 04/26/2023; Revised MM/DD/YYYY 
MARICOPA COUNTY AIR POLLUTION CONTROL REGULATIONS 
REGULATION II – PERMITS AND FEES 
RULE 205 
EMISSION OFFSETS GENERATED BY VOLUNTARY MOBILE 
SOURCE EMISSION REDUCTIONS CREDITS 
SECTION 100 – GENERAL 
101 
PURPOSE: To facilitate the creation and trading of mobile source emission reduction 
credits (MERCs) for use as offsets by a stationary sourcesources under Rule 240 
(Federal Major New Source Review (NSR)) of these rules by providing a process for: 
101.1 Generating mobile source emission reduction credits forMERCs from qualifying 
NOx or VOC emissions reductions achieved by permitted generators. 
101.2 Certifying creditsqualifying emission reductions as meeting offset requirements 
in advanceprior to issuance of a MERC certificate. 
101.3 Issuance of MERC certificates, including the certified credits’ userequirements 
for that purposeMERC generators and MERC users. 
101.3 Registering certified credits generated under this rule in the Arizona Emissions 
Bank. 
101.4 Using certified credits generated under this rule registered in the Arizona 
Emissions Bank. 
101.5 Using certified credits generated under this rule not registered in the Arizona 
Emissions Bank. 
102 
APPLICABILITY: The provisions of this rule shall apply to the following persons and 
entities: 
102.1 The owner or operator of a captive fleet of vehicles who holds or intends to 
obtain a Maricopa County Air Quality Department Stationary Source 
Permit(MCAQD) stationary source permit (generator permit) and has achieved or 
will achieve reductions in qualifying emissions in compliance with this rule. 
102.2 The owner or operator of a permittedany new major stationary source or major 
modification to an existing major stationary source that intends to use certified 
creditsMERCs as offsets. to obtain or revise a MCAQD stationary source permit 
(credit user permit). 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 49 of 125

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.and Rule 203 (Emission Reduction Credit (ERC) General Requirements) of the 
Maricopa County Air Pollution Control Regulations (MCAPCR). In the event of any 
inconsistency between any of the Maricopa County Air Pollution Control Regulations, the 
definitions in this rule take precedence. 
201 
ACCOUNT HOLDER: Any person or entity who has opened an account with the Arizona 
Emissions Bank. 
202 
ARIZONA EMISSIONS BANK: The system created by the Arizona Department of 
Environmental Quality (ADEQ) to record and make publicly available information on the 
issuance, certification, transfer, retirement, and use of emission reduction credits. 
203 201 
BASE YEAR EMISSION INVENTORY: The emission inventory used for a specific 
nonattainment national ambient air quality standard (NAAQS) that is used for required 
attainment plan demonstrations and transportation conformity determinations.  
202 
BASELINE EMISSIONS: The average rate at which a baselineemissions an original 
vehicle would havehas actually emitted the pollutant, as determined in absence of 
generating emission reductions during the two preceding calendars years, or two 
calendar years more representative of normal emissions within the 5-year period 
immediately before the reduction in qualifying emissionsAppendix A, § A. 
204 
BASELINE VEHICLE: Captive fleet vehicle that has been replaced or retrofitted for a 
reduction in qualifying emissions. 
205  203 
CAPTIVE FLEET: A fleet of vehicles where all the vehicles in the fleet are identifiable, 
the locations where they are being operated can be tracked and recorded, using a fleet 
management system, such as a global positioning system (GPS), their base of 
operation is in a nonattainment area within the jurisdiction of MCAQD, and which can 
serve as a permanent source of emission reductions when a vehicle is replaced or 
retrofitted. The captive fleet can only include on-road or off-road vehicles. 
206 
CERTIFIED EMISSION REDUCTION CREDIT: An emission reduction credit that has met 
the criteria in this rule for certification and has been issued by the Maricopa County Air 
Quality Department (MCAQD). Certified credits do not have property rights associated 
with them. 
207 204 
CREDIT USER: The applicant for a stationary source permit or permit revision (credit 
user permit) that intends to use MERCs as offsets for compliance with federal New 
Source Review requirements pursuant to Rule 240 of these rules. 
205 
EMISSION REDUCTION CREDIT (ERC): A reduction in qualifying emissions, expressed 
in tons per year as rounded down to the nearest one tenth (1/10) of a ton, for which a 
permitted generator has submitted an application pursuant to this rule. MCAQD issues 
ERCs for mobile sources as MERCs. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 50 of 125

208 206 
ENFORCEABLE: Specific measures for assessing compliance with an emissions 
limitation, control, or other requirement established in a permit or in this rule in a 
manner that allows compliance to be readily determined by, but not limited to, an 
inspection of records and reports. 
209 207 
FLEET MANAGEMENT SYSTEM: A system consisting of location tracking equipment 
and associated software. The system is used to track vehicle miles travelled (VMT) for 
fleet vehicles and is capable of distinguishing travel inside and outside the 
nonattainment area.  
208 
GENERATOR: The owner or operator of a captive fleet of vehicles that has obtained, or 
intends to obtain, a generator permit that has made, or proposes to make, reductions in 
qualifying emissions. 
209 
HISTORIC VEHICLE MILES TRAVELED (HVMT): The annual average VMT from the 
project’s original vehicles that make up the captive fleet. The annual average VMT shall 
be based on the annual actual VMT that occurred within the Phoenix-Mesa ozone 
nonattainment area, from the two preceding calendars years, or two calendar years 
more representative of normal operations within the 5-year period immediately before 
the reduction in qualifying emissions occurs. 
210 
LOAD SHIFTING: Shifting of activity, measured in VMT, of a replaced or retrofitted 
vehicle for which a MERC certificate has been issued to a higher emitting vehicle. 
211 
MERC CERTIFICATE: A document that certifies the issuance of MERCs by MCAQD in 
accordance with this rule, and includes the information specified in 301.3 b.(2). 
212 
MOBILE SOURCE EMISSION REDUCTION CREDIT (MERC): An ERC generated from a 
captive fleet vehiclevehicles. MERCs have no property rights associated with them. 
210 213 
MOVES: The latest version of the United States Environmental Protection Agency’s 
(EPA) Motor Vehicle Emission Simulator (MOVES) software. 
214 
NONATTAINMENT AREA: The Phoenix-Mesa ozone nonattainment area as defined in 
40 CFR Part 81.303 for any ozone NAAQS.  
215 
OFFSETS: Reductions in actual emissions required under Rule 240 (Federal Major New 
Source Review (NSR)) of these rules. 
211 
PERIODIC EMISSIONS INVENTORY: In accordance with section 172(c)(3) of the Clean 
Air Act, the base year emissions inventory within the Maricopa County nonattainment 
area for the relevant conventional air pollutant or the most recent periodic update. 
212 216 
ORIGINAL VEHICLE: A captive fleet vehicle that has been, or will be, replaced or 
retrofitted, to generate qualifying emission reductions. 
217 
PERMANENT: A reduction in qualifying emissions used to offset emissions increases 
that are enduring for the remaining life of the corresponding emissions increase. For the 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 51 of 125

purposes of this rule, an actual reduction in qualifying emissions that endure for at least 
20 years after the MERC certificate is issued. 
213 
PERMITTED GENERATOR: The owner or operator of a captive fleet of vehicles that has 
or intends to obtain a Maricopa County Air Quality Permit that has made or proposes to 
make reductions in qualifying emissions. 
214 218 
QUALIFYING EMISSIONS: Emissions of any conventional air pollutant quantifiedNOx or 
VOC emissions which are included in the periodic emissionscurrent ozone attainment 
plan base year emission inventory, other than elemental lead, or any precursor of a 
conventional air pollutant or any periodic update to such emission inventory, from any 
activityon road vehicle when generatedemitted within the Maricopa County 
nonattainment area associated with the conventional air pollutant. 
215 219 
QUANTIFIABLE: With respect to emissions, including the emissions involved in 
equivalent emission limits and emission trades, capable of being measured or 
otherwise determined in terms of quantity and addressed in terms of character. 
Quantification mayFor the purposes of this rule, quantification shall be based on 
MOVES output emission factors, for the baseline emissions, the replacement or retrofit 
vehicle emissions testing, monitored values, operating rates, and averaging times, 
materials used in a process or production, modeling, or other reasonable measurement 
practices.the VMT from the original vehicle. 
216 220 
REAL: A reduction in actual emissions previously released tointo the air resulting from a 
physical change or change to the method of operationsoperation by a permitted 
generator. 
217 221 
REPLACEMENT OR REPLACED VEHICLE: VehicleA vehicle that has, or will replace, an 
original vehicle, used to generate certified creditsqualified emission reductions, that is 
certified to an emission limit less than the baseline vehicle it replaces and is in 
compliance with the most recent applicable federal emission standard at the time of 
replacement. 
218 222 
RETROFIT OR RETROFITTED VEHICLE: Captive fleetAn original vehicle that has, or will 
have any, an alteration, including components, design, and instructions to perform this 
alteration, of the vehicle or engine, its fueling system, or the integration of these 
systems, that allows the vehicle or engine to operate on a fuel or power source different 
from the fuel or power source for which the vehicle or engine was originally certified; 
and that is designed, constructed, and applied in compliance with the applicable 
requirements in 40 CFR 85 and 86. 
219 223 
SURPLUS: A reduction in qualifying emissions below the emission limitations and 
standards used to comply with any otherwise federally applicable requirements and, 
including a required attainment plan, provided that the reduction is not relied upon to 
meet any requirements in the State Implementation Plan (SIP). 
224 
VEHICLE SOURCE TYPE: The specific type of vehicle, as listed in the most recent 
MOVES technical guidance document, including but not limited to: passenger cars and 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 52 of 125

trucks, light commercial trucks, transit buses, other buses, refuse trucks, single unit 
short- and long-haul trucks, and combination short- and long-haul trucks. 
SECTION 300 – STANDARDS 
301 
CERTIFICATION OF CREDITS FOR MOBILE SOURCEQUALIFIED EMISSION 
REDUCTIONS BY A PERMITTED GENERATOR: 
301.1 MERC Application: 
a. The permitted generator may apply for certified credits for reductions in
qualifying emissions for a vehicle replacement or retrofit that will comply with 
the applicable requirements in § 302 (MERC Generation) of this rule and by 
filing either of the following with the Control Officer in accordance with Rule 
210 (Title V Permit Provisions) or Rule 220 (Non-Title V Permit Provisions) of 
these rules: 
(1) An application for a permit revision seeking the imposition of conditions 
to make the reductions in qualifying emissions permanent and 
enforceable; or 
(2) An application for a permit seeking the imposition of conditions to make 
the reductions in qualifying emissions permanent and enforceable. 
b. An application for certified creditsobtain MERCs shall be filed withsubmitted
to the Control Officer on the form prescribed by the MCAQD and shall include:
(1) Information on the identity, type, ownership, and location of the permitted
generator; 
(2) InventoryAn inventory of the captive fleet, asincluding all information 
specified in § 504.2, for which a replaced or retrofitted vehicle resulted, or 
will result, in reductions in qualifying emissions; 
(3) A description of the vehicle replacementreplacements or retrofits that 
have resulted, or will result, in surplus reductions in qualifying emissions, 
as well as a description of how the reductions in qualifying emissions will 
be permanent; 
(4) Information on the methodology for quantifying the surplus reductions in 
qualifying emissions for each pollutant subject to the application, 
including emissions calculations, documentation of each original vehicle’s 
historic vehicle miles traveled, and how these rates were determined; 
(5) Information on the proper removal or disposal of baselineoriginal vehicles 
if the reductions in qualifying emissions were accomplished, or will be 
accomplished, through vehicle replacement; 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 53 of 125

(6) Information on the retrofit conversion systemprocess used, or to be used, 
if the reductions in qualifying emissions will be accomplished through 
vehicle retrofit; 
(7) Other information or records necessary to verify that the reductions in 
qualifying emissions qualify as permanent, quantifiable, surplus, federally 
enforceable, and real; 
(8) The actual date or anticipated date of the reductions in qualifying 
emissions, occurred, or will occur, as applicable; and 
(9) A signed statement by a responsible official, as defined in Rule 100 
(General Provisions and Definitions) of these rules, verifying the 
truthfulness and accuracy of all information provided in the application. 
301.2 Action on Application: The Control Officer shall review the application for 
certified credits and: 
a. EvaluateThe Control Officer shall review the application for MERCs and
evaluate whether the requested MERCs proposed qualifying emission
reductions will beresult in real, quantifiable, federally enforceable, permanent,
and surplus emission reductions, and determine whether the MERCs meet the
requirements of § 302 for generating MERCs.
b. If the Control Officer determines the requested credits will result in real,
quantifiable, federally enforceable, permanent, and surplus emission 
reductions, the generator shall submit an application with the Control Officer 
in accordance with the requirements of Rule 210 (Title V Permit Provisions) or 
Rule 220 (Non-Title V Permit Provisions) of these rules seeking either a permit 
revision or new permit to impose conditions to make the reductions in 
qualifying emissions permanent and enforceable. 
301.3 Generator Permit and MERC Certificate: The Control Officer, upon completion of 
evaluation of the applications under § 301.2, shall perform the following: 
a. Provide public participation on the Control Officer’s proposed determination
to issue certified creditsMERCs, and a generator permit or permit revision, per
the provisions in Section§ 407 of Rule 220 of these rules. This requirement
applies to all proposed actions to issue certified creditsMERCs according to
this rule. The proposed determination shall include the proposed generator
permit or permit revision, and the Control Officer’s underlying analysis for
proposing to certify the MERCs.
b. Upon completion of § 301.3 a., if the Control Officer determines the requested
credits meet the requirements of this rule§ 301.2 a. and should be certified,
then the Control Officer shall:
(1) Issue either a generator permit or permit revision that incorporates the
requirements of § 302.2, and any other necessary requirements to make 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 54 of 125

the reductions in qualifying emissions permanent and 
enforceable.federally enforceable. The generator permit or permit revision 
shall include the following: 
(a) The quantity of VMT used to determine the number of MERCs issued; 
(b) The qualifying emission reduction emission factor for each vehicle 
type and engine model year in the fleet in grams/mile, as calculated 
pursuant to Appendix A, § D; and 
(c) The date by which the qualifying emission reductions are required to 
be implemented. 
(2) Issue one certified credit for each tona MERC certificate for the total 
tonnage of MERCs, as rounded down to the nearest one tenth (1/10) of a 
ton, per year of reduction. The MERC certificate shall include the following 
information: MERC certificate number, date of issuance, name and 
address of the generator, description of activity that qualifies as 
permanent, quantifiable, surplus, federally enforceableresulted in the 
qualified emission reductions, and real. 
(3) Provide the applicant with a certificate representing the number of 
certified creditsMERCs issued. The MERC certificate shall specify that the 
credits were certified under this rule, and shall specify whether the 
reductions in qualifying emissions have been implemented or the date by 
which the reductions are required to be implemented. In addition, the 
certificate shall include the following: 
(a) The quantity of VMT used to determine the number of MERCs issued; 
(b) The qualifying emission reduction emission factor for each vehicle 
type and engine model year in the fleet in grams/mile, as calculated 
pursuant to Appendix A, § D; 
(c) A statement that the new stationary source relying on the emissions 
offsets from a MERC may not commence operation until the emissions 
reductions corresponding to that MERC have actually occurred; and 
(d) A statement that the MERC does not provide any property rights. 
c. If the Control Officer determines that none of the requested MERCs should be
certified, then the applicant will be notified, and no credits will be issued and
noneither a generator permit or, nor permit revision, will be issued.
301.34Registration of Certified CreditsMERCs in the Arizona Emissions Bank: A MERC 
Certificate (Certified credits) may be registered in the Arizona Emissions Bank 
but registration is not required. See § 303 (RegistrationSee Rule 203 (Emission 
Reduction Credit (ERC) General Requirements) of Certified Credits in the Arizona 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 55 of 125

Emissions Bank) of this rulethese rules for procedures regarding registration of 
certified creditsMERCs in the Arizona Emissions Bank. 
302 
MERC GENERATION: A permitted generator that plans to replace or retrofit all or part of 
their captive fleet to generate a reduction in qualifying emissions reductions: 
302.1 May apply to certifyfor issuance of MERCs by meeting the following 
requirements: 
a. Location: Demonstrate that the captive fleet of vehicles used to generate
credits shall beMERCs are based and operated within athe nonattainment
area within the jurisdiction of the MCAQD. Certified credits. MERCs may only
be granted for those reductions generated while operating in the
nonattainment area. A baseline vehiclesAn original vehicle’s operation inside
and outside the nonattainment area must be quantifiable.
b. Quantification of Baseline Emissions: The permitted generator shall quantify
baseline emissions for each original vehicle within the captive fleet that will
be replaced or retrofitted following the calculation methodology in Appendix
A (Calculations for Determining Emission Reductions from Each Vehicle
Replacement or Retrofit) of this rule.
c. Quantification of Emission Reductions:
(1) The permitted generator shall quantify the post project emissions for each
original vehicle within the captive fleet that will be replaced or retrofitted 
followingusing the calculation methodology specified in Appendix A 
(Calculations for Determining Emission Reductions from Each Vehicle 
Replacement or Retrofit) of this rule. 
(2) Calculations shall only include surplus reductions and shall not include 
emission reductions created or used under any other emissions trading 
program, emission reductions used to satisfy the State Implementation 
Plan including transportation conformity requirements, or any emissions 
reductions pursuant to a federal consent decree, or state and local 
settlements. 
d. Alternative Calculation Methodology: A permitted generator may use an
alternative calculation methodology to quantify emission reductions upon
approval from the Control Officer and the Administrator. All alternative
calculation methodologies shall be submitted to the Administrator after
completion of the public participation process in § 301.2,3 a., and shall
include any public comments received and the Control Officer’s response to
the public comments. The Administrator shall be provided 60 days to review
the submittal. Written approval from the Administrator is requiredmust be
obtained prior to using an alternative calculation methodology.
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 56 of 125

302.2 Shall comply with all of the following installation, operating, maintenance, 
monitoring, removal/disposal, replacement, and recordkeeping requirements: 
a. Operation and Maintenance: The permitted generator shall operate and
maintain the replacement and/or retrofitted vehicles in accordance with the
manufacturer’s written instructions, or the maintenance schedule provided by
the manufacturer’s authorized service provider.
b. Monitoring of Captive Fleet:  Management System:
(1) Fleet Management System Installation, Operation, and Maintenance:
(a) The permitted generator shall monitor install and maintain a fleet 
management system capable of tracking and recording the 
replacementlocation and VMT of each replaced or retrofitted vehicles 
invehicle for which a MERC certificate is issued. The system must 
differentiate and record travel within and outside of the captive 
nonattainment area;  
(b) The generator shall operate the fleet usedmanagement system to 
generate credits as specified in § 503 to ensure the monitor and record 
the monthly VMT within the nonattainment area for each replaced or 
retrofitted vehicles continue to generate permanent emission 
reductions as represented in the application in § 301.1(b)(3).vehicle for 
which a MERC certificate is issued; and 
(c) The generator shall update, operate and maintain the fleet 
management system in accordance with the manufacturer’s written 
instructions. 
(2) Fleet Management System Exemption: A generator may be exempt from 
compliance with the fleet management system requirements of 302.2 
b.(1) if captive fleet operations for which a MERC certificate is issued 
occur entirely within the nonattainment area. The generator must submit 
to the Control Officer for approval documentation demonstrating the 
operations occur entirely within the nonattainment area. Such 
documentation may include, but is not limited to, local regulation or 
company policy restricting VMT to within the nonattainment area. In 
addition, the generator must demonstrate how the monthly VMT will be 
monitored and recorded in absence of a fleet management system. 
c. Removal/Disposal of Replaced BaselineOriginal Vehicles that were
Replaced: The permitted generator shall permanently remove any baseline
vehicles replaced from the applicable nonattainment area or render the
baselineThe generator shall remove or dispose of all original vehicles for
which a MERC was issued. Removal shall consist of permanently removing all
original vehicles at least 200 miles from the nonattainment area. Disposal
shall consist of rendering the original vehicles permanently disabled and
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 57 of 125

disposedisposed of in a manner that complies with all applicable local, state, 
and federal laws. The permittedOriginal vehicles shall not be relocated to any 
current ozone nonattainment area, as designated on the date of MERC 
issuance. The generator shall maintain documentation demonstrating proper 
removal or disposal of the baselineall original vehicles. To demonstrate a 
baselinean original vehicle was properly removed from the nonattainment 
area, the documentation shall include a bill of sale, vehicle registration, or 
other transfer documentation demonstrating the vehicle has been removed 
greater than 200 miles away from all Maricopa County nonattainment 
areasremoved vehicle complies with the location requirements described 
above. 
d. Subsequent Vehicle Replacements: The replacement or retrofitted vehicles
that were used to acquire certified creditsMERCs shall only be subsequently
replaced with vehicles certified to an emission limit equivalent tothe same, or
less than the replacement or retrofitted vehicle used to acquire certified
credits and shall comply with the most recent applicable federallower, EPA 
emission standard. This replacement requirement shall continue for 20 years 
from the issuance date of the certified credits. The permitted generator shall 
further ensure that any replaced baseline vehicle is not operated in any other 
captive fleet owned or operated by the permitted generator in the applicable 
Maricopa County nonattainment area.MERC certificate. 
e. Vehicle Retrofit: The permitted generator shall ensure the retrofit vehicle
used for generating certified creditsMERCs satisfies the exemption from
tampering prohibition of clean alternative fuel conversions through
compliance with 40 CFR 85, Subpart F, and a valid corresponding certificate
of conformity or notification submission to the EPA.
f.
Timing: The permitted generator shall demonstrate that the vehicle
replacements or retrofits, and removal/disposal of baselineoriginal vehicles,
occurred prior to the application for certified credits or shall meet an
enforceable timeline established in the permit or permit revision required by §
301.2(c)(1) that specifies how and by when this demonstration will be 
met.either: 
(1) The application for MERCs; or 
(2) The enforceable date established in the generator permit or permit 
revision required by § 301.3 b.(1)(c) that specifies the date by which 
reductions in qualifying emissions must be implemented. 
g. Monitoring and Recordkeeping: Upon issuance of a generator permit or
permit revision under this rule, a permitted generator is responsible for
creating and maintaining records from their captive fleet monitoring and
recordkeeping as required in: 
(1) Section 501 (Recordkeeping and Records Retention); 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 58 of 125

(2) Section 502 (Inspections); 
(3) Section 503 (MERC Generation Monitoring); and 
(4) Section 504 (MERC Generation Records).; and 
(5) Section 505 (Compliance Demonstration). 
303 
REGISTRATION OF CERTIFIED CREDITS IN THE ARIZONA EMISSIONS BANK: The 
permitted generator may register certified credits with the Arizona Emissions Bank. To 
register a certified credit: 
303.1 Owner or Operator: The permitted generator shall: 
a. Indicate on the MCAQD emission reduction credit application their plan to
register the certified credits in the Arizona Emission Bank; and 
b. Open an Arizona Emissions Bank account per A.A.C. R18-2-1206.A.
303.2 Control Officer: The Control Officer shall notify the ADEQ of the number of 
certified credits issued to the permitted generator on a form prescribed by the 
ADEQ. 
303 
USE OF THE CERTIFIED CREDITS:MERC CERTIFICATES 
304.1 Certified Credits Registered in the Arizona Emissions Bank: 
a. An account holder who intends to use the certified credits under this rule held
in its account as offsets shall file an application to use the certified credits on 
the form prescribed by the ADEQ. 
b. On approval of the application by the ADEQ, the Control Officer shall review
the certified credits under Section 304 of this rule and either: 
(1) Approve the use of the certified credits as offsets under Rule 240 (Federal 
Major New Source Review) of these rules and: 
(a) Notify the user of certified credits that may be included in the permit or 
permit revision application of the stationary source; and 
(b) If there are any remaining available certified credits, the Control Officer 
will reissue the certificate with a sequential revision number. This will 
provide documentation on the availability of the remaining certified 
credits. 
(2) Deny the use of the certified credits for offsets under Rule 240 (Federal 
Major New Source Review) of these rules and: 
(a) Provide written notification of the reason for denying the use of the 
certified credits as offsets; and 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 59 of 125

(b) If there are any remaining available certified credits, the Control Officer, 
as applicable, will return the certificate to the owner or operator of the 
stationary source or reissue the certificate with a sequential revision 
number. This will provide documentation on the availability of the 
remaining certified credits. 
c. The Control Officer shall provide notice to the ADEQ of the final action on the
stationary source’s application for a permit or for a permit revision and of any 
changes in the number of certified credits. 
d. Reductions in qualifying emissions reflected in the number of certified credits
shall be implemented before actual operation of the new stationary source or 
modification begins. 
304.2 Certified Credits Not Registered in the Arizona Emissions Bank: 
a. The owner or operator of a stationary source who intends to use certified
credits that are not registered in the Arizona Emissions Bank as offsets shall: 
(1) Notify the MCAQD of the intention to use the certified credits as an offset 
to meet the requirements of Rule 240 (Federal Major New Source Review) 
of these rules; and. 
(2) Submit the certificate of issued certified credits to the MCAQD in 
conjunction with a stationary source permit application or permit revision. 
b. The Control Officer shall review the certified credits under Section 304 of this
rule and either: 
(1) Approve the use of the certified credits as offsets under Rule 240 (Federal 
Major New Source Review) of these rules and: 
(a) Notify the owner or operator of the number of certified credits that may 
be included in the permit or permit revision application of the 
stationary source; and 
(b) If there are any remaining available certified credits, the Control Officer 
will reissue the certificate with a sequential revision number. This will 
provide documentation on the availability of the remaining certified 
credits. 
(2) Deny the use of the certified credits for offsets under Rule 240 (Federal 
Major New Source Review) of these rules and: 
(a) Provide written notification of the reason for denying the use of the 
certified credits as offsets; and 
(b) If there are any remaining available certified credits, the Control Officer, 
as applicable, will return the certificate to the owner or operator of the 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 60 of 125

stationary source or reissue the certificate with a sequential revision 
number. This will provide documentation on the availability of the 
remaining certified credits. 
304.3 First In, First Out Accounting: The owner or operator of the stationary source 
using certified credits must use the oldest credits in their possession first. 
303.1 General Use Requirements: See Rule 203 (Emission Reduction Credit (ERC) 
General Requirements) of these rules for procedures regarding the use of MERCs 
as offsets to comply with the NSR requirements of Rule 240. 
304.4 Review303.2 Review of MERC Integrity: At the time of use of certified credits 
under this rulePrior to issuing a credit user permit, the Control Officer shall 
reviewverify that the amount of previouslyMERCs issued certified creditsin the 
surrendered MERC certificate remain surplus under(as defined in this rule) as of 
the date of permit issuance, and shall revise the MERC certificate amount if 
necessary to maintain surplus integrity. Any certified creditsMERC certificate 
proposed to be used where the reductions in qualifying emissions were not 
implemented at the time of MERC application shall only be used if the MERC 
certificate states that the emission reductions will be implemented beforeon a 
date prior to the date the new stationary source or modification using the credits 
beginsplans to commence operation of the new source or modification.  
303.3 Credit User Commencement of Operation: The credit user shall not commence 
operation of their permitted new source or modification until the generator has 
demonstrated compliance with § 401.1. 
SECTION 400 – ADMINISTRATIVE REQUIREMENTS 
401 
FEES 
401.1 A fee may be charged for the following: 
a. Preliminary ERC Calculations Review: For all time required by the Control
Officer to review the ERC calculations, at a rate of $149.20 per hour and 
adjusted annually under § 401.2 of this rule. When review of ERC calculations 
is complete the Control Officer shall send an itemized invoice. The invoice 
shall indicate the total cost of reviewing ERC calculations and the balance 
due. 
b. ERC Application Processing (for Certification):
(1) The minimum fee due shall be an application fee of $200. 
(2) For all time required by the Control Officer to review the ERC calculations, 
at a rate of $149.20 per hour and adjusted annually under § 401.2 of this 
rule. When application processing is completed and final costs are greater 
than the combined fees under §§ 401.1a and b(1) of this rule, the Control 
Officer shall send an itemized invoice. The invoice shall indicate the total 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 61 of 125

cost of evaluating and acting upon the application, minus the fee 
submitted under § 401.1a of this rule, and the balance due. 
c. Permit: Permit fees applicable to either §§ 301.1a or b of this rule, as set
forth in Rule 280 (Fees) of these rules. 
401.2 Fee adjustments: The Control Officer shall adjust the hourly rate in §§ 401.1a & b every 
January 1, to the nearest 10 cents per hour, beginning on January 1, 2018. The Control 
Officer will multiply $149.20 by the Consumer Price Index (CPI) for the most recent year 
and then divide by the CPI for the year 2016. 
401 OFFSET INTEGRITY RESPONSIBILITIES: 
401.1 Generator Implementation Notification: The generator shall provide written 
notification to the Control Officer and credit user within 48 hours of completing 
implementation of the qualifying emission reductions for which a MERC 
certificate was issued under this rule, and provide documentation demonstrating 
compliance with §§ 302.2 b., 302.2 c., 302.2 e., and 302.2 f.(2), as applicable. 
401.2 Generator Monthly VMT Review Requirements 
a. For each calendar month, the generator shall review the 12-month rolling VMT
as calculated in § 505 to determine if the 12-month rolling VMT achieved by 
the generator equals, or exceeds the quantity of VMT specified in their MERC 
certificate.  
(1) If the 12-month rolling VMT achieved by the generator is equal to or 
greater than the quantity of VMT specified in their MERC certificate, the 
generator shall record the results pursuant to § 505. No further action is 
required.  
(2) If the 12-month rolling VMT achieved by the generator is discovered to be 
less than the quantity of VMT specified in their MERC certificate, the 
generator shall:  
(a) Provide a copy of the data to the Control Officer within 5 business days 
of the date of discovery showing the total 12-month rolling VMT 
achieved; and 
(b) Comply with one of the following: 
(i) DEMONSTRATION OF CONTINUED COMPLIANCE: The generator 
shall provide a demonstration to the Control Officer for approval 
within 30 days of VMT shortfall date of discovery to show that the 
lower VMT was not a result of load shifting and the integrity of the 
MERCs continue. If the demonstration is approved by the Control 
Officer no further action is required. If the demonstration does not 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 62 of 125

receive approval, the generator shall notify the credit user, as 
described in § 401.2 a.(2)(b)(ii). 
(ii) CREDIT USER NOTIFICATION: The generator shall notify the credit 
user of the VMT shortfall within 5 business days of the date of 
discovery or within 5 business days of receiving a disapproval of 
the demonstration of compliance from the Control Officer. The 
credit user shall conduct the VMT shortfall evaluation as described 
in § 401.3. 
401.3 Credit User VMT Shortfall Evaluation  
a. If the credit user is notified by a generator, pursuant to § 401.2 a.(2)(b)(ii),
that their 12-month rolling VMT is less than the quantity of VMT specified in 
the corresponding MERC certificate relied upon for NSR permit issuance, then 
the credit user shall satisfy the requirements of § 401.3 b.  
b. Conduct the following calculations and analysis:
(1) Calculate the Emission Reduction Shortfall (ERS) by subtracting the VMT 
achieved, as reported by the credit generator pursuant to § 401.2 a.(2), 
from the VMT required in the MERC certificate, and multiplying the 
difference by the applicable qualifying Emission Reduction Emission 
Factor (EREF) specified in the MERC certificate. Where: ERS in tons/yr = 
[(required VMT - achieved VMT) x EREF (in grams/mile)]/907,184.74. 
(2) If the calculated ERS in 401.3 b.(1) is less than 10% of the total MERCs 
issued by the Department to the generator under Section 301.3 b.(2), then 
the credit user or generator shall submit an action plan to the Control 
Officer for approval within 15 days of notification by the generator 
describing how the  offset emissions shortfall will be remedied no later 
than 3 calendar months after the calendar month that the VMT shortfall 
occurred. This may include documentation demonstrating the credit user’s 
actual emissions for the specific NSR permit issuance that relied on 
MERCs are still sufficiently offset despite the VMT shortfall. A credit user 
or generator that is required to submit a plan by this section must fully 
comply with the plan, which has been submitted but not yet been 
approved, unless notified otherwise by the Control Officer in writing. 
(3) If the calculated ERS in 401.3 b.(1) is 10% or higher of the total MERCs 
issued by the Department to the under Section 301.3 b.(2), or MCAQD 
does not receive an action plan to comply paragraph (2) of this section, or 
MCAQD does not approve the action plan submitted pursuant to 
paragraph (2) of this section, then the credit user shall submit a permit 
application within 90 days of notification by the Control Officer that 
provides an equivalent quantity of reductions as the ERS determined under 
section 401.3 b.(1). This may be accomplished by any combination of the 
following: 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 63 of 125

(a) Permanently reducing emissions by revising existing permit emission 
or throughput limits; or 
(b) Providing valid ERCs or MERCs in a quantity equivalent to the ERS 
determined under section 401.3 b.(1). 
(4) A credit user that operates without adequate offsets is in violation of 
these rules. 
402 
ENFORCEMENT AUTHORITY: Nothing herein restricts independent enforcement 
authorities under the Clean Air Act by other parties. 
SECTION 500 – MONITORING AND RECORDS 
501 
RECORDKEEPING AND RECORDS RETENTION: RecordsThe records and data required 
by this section shall be: 
501.1 Kept on site at all times by the permitted generator in a consistent and complete 
manner, in either electronic or paper format. 
501.2 UponMade available to the Control Officer no later than five business days upon 
verbal or written request by the Control Officer, the log or the records and 
supporting documentation shall be provided as soon as possible but no later 
than 48 hours after the request. 
501.3 Unless otherwise specified, maintained for five (5) years after the record is 
created. 
501.4 Maintained without falsification. 
501.5 Made available to the Control Officer upon written request by members of the 
public using the County’s public records request process. 
502 
INSPECTIONS: A permitted generator shall provide the Control Officer with access to 
the premises for the purpose of conducting an inspection to verify compliance with this 
rule. An inspection may include, but is not limited to, a review of records and reports. 
503 
MERC GENERATION MONITORING: The permitted generator shall monitor parameters 
used to quantify certified creditsMERCs beginning no later than issuance of the certified 
credits. All monitoring equipment shall be operated and maintainedMERC certificate or 
the enforceable date established in accordance with the manufacturer’s written 
instructions.the generator permit or permit revision required by § 301.3 b.(1). At a 
minimum, the permitted generator shall monitor the following for each replaced or 
retrofitted vehicle used for obtaining certified creditsa MERC certificate: 
503.1 Vehicle miles traveled (VMT) as determined by GPS tracking; 
503.2 Percent of VMT within the nonattainment area as determined by GPS tracking; 
and 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 64 of 125

503.1 VMT within the nonattainment area as determined by the fleet management 
system or alternative method for a generator exempt from the fleet management 
system requirements; 
503.23Any other parameter used to make the certified creditsMERCs quantifiable, such 
as idling speed, idling emissions, or fuel use rate. 
504 
MERC GENERATION RECORDS: A permitted generator shall maintain the following 
records offor each replacement or retrofitted vehicle in its captive fleetfor which a 
MERC certificate was issued: 
504.1 Certified Credit RecordsMERC Documentation: All records supportingsubmitted 
with the application for which certified credits were granted, including but not 
limited to: documentation of when a vehicle was retrofitted or replaced, 
documentation that the baselineoriginal vehicle or baselineoriginal vehicle engine 
was disposed of orproperly removed fromand/or destroyed, as required by § 
302.2 c., and documentation demonstrating the nonattainment area, VMTHVMT 
for each baselineoriginal vehicle used to generate credits, and percent of 
VMTthat occurred within the nonattainment area for each baseline vehicle used 
to generate credits. The. These records shall be maintained for at least 5five 
years followingafter the use of the certified creditsMERCs to obtain a NSR 
permit, regardless of any defenses under any federal or state statute of 
limitations. 
504.2 ReplacementReplaced or Retrofitted Vehicle Inventory Records: A detailed 
inventory of each replacementreplaced or retrofitted vehicle used to generate 
certified credits thatMERCs shall include all of the following information and 
shall be reviewed and updated on a monthly basis: 
a. For each fleetreplaced or retrofitted vehicle provide:
(1) The vehicle manufacturer.
(2) The model number.
(3) The model year.
(4) A description of the The vehicle including serialsource type.
(5) Serial number.
(56)Fuel type.
b. The date each replaced or retrofitted vehicle was:
(1) Added to the inventory and began operation.
(2) Removed from the inventory.
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 65 of 125

c. ForAfter the initial project, for each vehicle added to the inventory:
(1) Identify the vehicle removed in its place.
(2) The permitted generator must document that the replacement vehicle is
certified to equivalent or lower standards than the vehicle or engine used 
to generate certified creditsMERCs. 
504.3 Operational Records: The following operational records shall be maintained on a 
monthly basis upon issuance of the certified creditsMERC certificate or when the 
generator notifies the MCAQD that the project has been completed, as 
applicable: 
a. Monthly: For each replacement or retrofitted vehicle used to generate
certified credits, the permitted generator shall record aA description of all 
maintenance and repairs, including the resultsrepair activities, current vehicle 
mileage, date the activity occurred, and any corrective actions performed. 
b. Monthly: For each replacement or retrofitted vehicle in the captive fleet,
maintain monthly records of: 
(1) Calendar month VMT. 
(2) To date for the calendar year, the percent of VMT within the applicable 
nonattainment area. 
b. The calendar month VMT that occurred within the nonattainment area for
each vehicle as recorded by the fleet management system or alternative 
method for a generator exempt from the fleet management system 
requirements. The VMT records shall be aggregated by the vehicle source 
type. 
c. Quarterly records demonstrating that all fleet management system software
and maps have been updated to the most current version. 
d. For any generator operating under the fleet management exemption in 302.2
b.(2), a record of any VMT outside the nonattainment area. 
(3) Monthly  
e. Summary of any other monitoring required by Section§ 503 of this rule.
504.4 Vehicle Retrofit Records: The permitted generator shall maintain a record for 
each retrofitted vehicle that was used to generate certified creditsMERCs that 
demonstrates exemption from tampering prohibition of clean alternative fuel 
conversions by compliance with 40 CFR 85, Subpart F. This includes the 
applicable valid certificate of conformity or notification submission to the EPA. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 66 of 125

504.5 Annual Report: Upon issuance of certified credits, and within 60 days after 
December 31 of each calendar year, the permittedThe generator shall submit an 
annual report to the Control Officer summarizing the captive fleet’s operation and 
compliance with § 302.2( b). for the previous calendar year and provide: attest, 
within 60 days after December 31 of each calendar year. The report shall include 
the following: a statement attesting that any replaced baselineoriginal vehicle is 
not a part of any other captive fleet owned or operated by the permitted 
generator in Maricopa County within 200 miles of the nonattainment area and 
how this was verified, the current captive fleet inventory as specified by § 504.2, 
total annualthe VMT for each vehicleby the fleet of vehicles used to generate 
certified credits, and percentage of VMT each vehicle usedMERCs within the 
nonattainment area during the previous calendar year. Additionally, any generator 
that operates under the fleet management system exemption in Section 302.2 
b.(2) must provide a statement attesting that operations continue to generate 
certified credits accruedoccur entirely within the nonattainment area per the 
documentation provided in the applicable nonattainment area that calendar 
year.Section 302.2 b.(2). 
505 
COMPLIANCE DEMONSTRATION: Within 30 days of the end of each month, the 
generator shall: 
505.1 Record the amount of VMT within the nonattainment area for each replacement 
or retrofitted vehicle during the preceding month and record the VMT sum for all 
replacement or retrofitted vehicles, aggregated by vehicle source type. 
505.2 Calculate and record the 12-month rolling total of VMT within the nonattainment 
area. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 67 of 125

Rule 205 APPENDIX A 
CALCULATIONS FOR DETERMINING EMISSION REDUCTIONS FROM 
EACH VEHICLE REPLACEMENT OR RETROFIT PROJECTS
A. Baseline Emissions = Annual Utilization(g/year) = HVMT (miles/year) × Baseline 
Pollutant Emission Factor (g/mile) 
1. Where g is grams of pollutant emitted.
2. Annual Utilization is the aggregate number of annual average miles (using
historical data for the two-year period selected according to the definition of 
baseline emissions in this rule) of actual vehicle utilization within the applicable 
nonattainment areaWhere HVMT as defined in § 209. 
3. Where the Baseline Pollutant Emissions Factor is determined using the baseline
vehicle fuel type, baseline vehicle engine modyear, and the on-road vehicle
emissions factors, in g/mile, inis determined by running the latest applicable 
version of the United States Environmental Protection Agency’s (EPA) Motor 
Vehicle Emission Simulator (MOVES) software. Baseline. The data points needed 
to run the MOVES model includes, but is not limited to, the following:  
(a) Original vehicle fuel type, 
(b) Original vehicle engine model year, 
(c) Aggregated HVMT per vehicle source type, and 
(d) The vehicle type of the fleet vehicles. 
4. Based on this input, the MOVES model will output the total emissions from the
baseline fleet based on an original vehicle engine model year corresponds to the 
calendar year in which the emission reductions are generated by replacing or 
retrofitting the baseline vehicle. The above calculations yield (g/year.). To obtain 
tons/yr, the regulatory quantity, multiply by 1.1 x 10-6. To determine a g/mile 
emission factor, this emission total shall be divided by the input HVMT per 
vehicle type (miles/year). 
B. Post Project Emissions = Annual Utilization(g/year) = HVMT (miles/year) × Post-
Project Pollutant Emission Factor (g/mile) 
1. Where g is grams of pollutant.
2. Annual Utilization isWhere HVMT as defined in § 209.
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 68 of 125

3. Where the value from A.2.Post Project Pollutant Emissions Factor, in g/mile, is
determined using the replacementby running the latest version of MOVES. The
data points needed to run the MOVES model includes, but is not limited to, the
following, as applicable:
(a) Replacement or retrofit vehicle fuel type, replacement
(b) Replacement or retrofit vehicle engine model year, and the on-road
(c) Aggregated HVMT per vehicle emissions factors, in g/mile, in the latest
applicable version of type, and  
(d) The vehicle type of the EPA’s MOVES software. fleet vehicles. 
For a retrofitted vehicle, the vehicle engine model year corresponds to the year 
the emission reductions are generated by retrofitting the baseline vehicle. For a 
replacement vehicle, the replacement vehicle engine model year corresponds to 
the model year of the replacement vehicle.original vehicle.  
For a replacement vehicle, the replacement vehicle engine model year 
corresponds to the model year of the replacement vehicle. 
4. The above calculations yield Based on this input, the MOVES model will output
the total emissions from the replacement or retrofitted fleet based on a vehicle
engine model year (g/year.). To obtain tons/yr, the regulatory quantity, multiply by
1.1 x 10-6. To determine a g/mile emission factor, this emission total shall be
divided by the input HVMT per vehicle type (miles/year).
C. The amount of eligible emission reduction credits for each vehicle is 
determinedcalculated by subtracting Post Project Emissions from Baseline 
Emissions.  
D. High Pollution Area Incentive: The permitted generator may be eligible to use an 
earlier baseline vehicle engine model year to determine the amount of eligible 
emission reduction credits determined in Section C of this Appendix if the permitted 
generator can demonstrate the annual utilization of the vehicle occurs at least 75% 
of VMT within areas of high pollution as identified through EPA’s EJScreen 
(Environmental Justice Screening and Mapping Tool) Environmental Justice 
Indexes. An area of high pollution shall be considered any area in the 90th national 
percentile or greater for the credited pollutant or applicable precursors. To be 
eligible, a gasoline baseline vehicle engine must be no more than 7 years older than 
the replaced or retrofitted vehicle engine or a diesel baseline vehicle engine must be 
no more than 11 years older than the replaced or retrofitted vehicle engine. Once 
determined to be eligible, vehicles may use a baseline vehicle engine model year that 
corresponds to the model year of the baseline vehicle. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 69 of 125

D. The qualifying emission reduction emission factor for each vehicle type and engine 
model year in the fleet is calculated by subtracting the Post Project Pollutant 
Emissions Factor from the Baseline Pollutant Emissions Factor, grams/mile. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 70 of 125

MARICOPA COUNTY AIR POLLUTION CONTROL REGULATIONS 
REGULATION II – PERMITS AND FEES 
RULE 205 (EMISSION OFFSETS GENERATED BY VOLUNTARY 
MOBILE SOURCE EMISSION REDUCTIONS) 
INDEX 
SECTION 100 – GENERAL 
101 
PURPOSE 
102 
APPLICABILITY 
SECTION 200 – DEFINITIONS 
201 
BASE YEAR EMISSION INVENTORY 
202 
BASELINE EMISSIONS 
203 
CAPTIVE FLEET 
204 
CREDIT USER 
205 
EMISSION REDUCTION CREDIT (ERC) 
206 
ENFORCEABLE 
207 
FLEET MANAGEMENT SYSTEM 
208 
GENERATOR 
209 
HISTORIC VEHICLE MILES TRAVELED (HVMT) 
210 
LOAD SHIFTING 
211 
MERC CERTIFICATE 
212 
MOBILE SOURCE EMISSION REDUCTION CREDIT (MERC) 
213 
MOVES 
214 
NONATTAINMENT AREA 
215 
OFFSETS 
Clean version without the strikethrough/underline 
Return to list of attachments
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 71 of 125

216 
ORIGINAL VEHICLE 
217 
PERMANENT 
218 
QUALIFYING EMISSIONS 
219 
QUANTIFIABLE 
220 
REAL 
221 
REPLACEMENT OR REPLACED VEHICLE 
222 
RETROFIT OR RETROFITTED VEHICLE 
223 
SURPLUS 
224 
VEHICLE SOURCE TYPE 
SECTION 300 – STANDARDS 
301 
CERTIFICATION OF QUALIFIED EMISSION REDUCTIONS 
302 
MERC GENERATION 
303 
USE OF THE MERC CERTIFICATES 
SECTION 400 – ADMINISTRATIVE REQUIREMENTS 
401 
OFFSET INTEGRITY RESPONSIBILITIES 
402 
ENFORCEMENT AUTHORITY 
SECTION 500 – MONITORING AND RECORDS 
501 
RECORDKEEPING AND RECORDS RETENTION 
502 
INSPECTIONS 
503 
MERC GENERATION MONITORING 
504 
MERC GENERATION RECORDS 
505 
COMPLIANCE DEMONSTRATION 
APPENDIX TO RULE 205 
APPENDIX A – CALCULATIONS FOR DETERMINING EMISSION REDUCTIONS FROM 
VEHICLE REPLACEMENT OR RETROFIT PROJECTS 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 72 of 125

Adopted 04/26/2023; Revised MM/DD/YYYY 
MARICOPA COUNTY AIR POLLUTION CONTROL REGULATIONS 
REGULATION II – PERMITS AND FEES 
RULE 205  
EMISSION OFFSETS GENERATED BY VOLUNTARY MOBILE 
SOURCE EMISSION REDUCTIONS 
SECTION 100 – GENERAL 
101 
PURPOSE: To facilitate the creation and trading of mobile source emission reduction 
credits (MERCs) for use as offsets by stationary sources under Rule 240 (Federal Major 
New Source Review (NSR)) of these rules by providing a process for: 
101.1 Generating MERCs from qualifying NOx or VOC emissions reductions achieved 
by generators. 
101.2 Certifying qualifying emission reductions as meeting offset requirements prior to 
issuance of a MERC certificate. 
101.3 Issuance of MERC certificates, including the requirements for MERC generators 
and MERC users. 
102 
APPLICABILITY: The provisions of this rule shall apply to: 
102.1 The owner or operator of a captive fleet of vehicles who holds or intends to 
obtain a Maricopa County Air Quality Department (MCAQD) stationary source 
permit (generator permit) and has achieved or will achieve reductions in 
qualifying emissions in compliance with this rule. 
102.2 The owner or operator of any new major stationary source or major modification 
to an existing major stationary source that intends to use MERCs as offsets to 
obtain or revise a MCAQD stationary source permit (credit user permit). 
SECTION 200 – DEFINITIONS: For the purpose of this rule, the following definitions shall 
apply in addition to definitions found in Rule 100 (General Provisions and Definitions) and Rule 
203 (Emission Reduction Credit (ERC) General Requirements) of the Maricopa County Air 
Pollution Control Regulations (MCAPCR). In the event of any inconsistency between any of the 
Maricopa County Air Pollution Control Regulations, the definitions in this rule take precedence. 
201 
BASE YEAR EMISSION INVENTORY: The emission inventory used for a specific 
nonattainment national ambient air quality standard (NAAQS) that is used for required 
attainment plan demonstrations and transportation conformity determinations.  
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 73 of 125

202 
BASELINE EMISSIONS: The emissions an original vehicle has actually emitted, as 
determined in Appendix A, § A. 
203 
CAPTIVE FLEET: A fleet of vehicles where all the vehicles in the fleet are identifiable, 
the locations where they are being operated can be tracked and recorded using a fleet 
management system, such as a global positioning system (GPS), their base of 
operation is in a nonattainment area, and which can serve as a permanent source of 
emission reductions when a vehicle is replaced or retrofitted. The captive fleet can only 
include on-road vehicles. 
204 
CREDIT USER: The applicant for a stationary source permit or permit revision (credit 
user permit) that intends to use MERCs as offsets for compliance with federal New 
Source Review requirements pursuant to Rule 240 of these rules. 
205 
EMISSION REDUCTION CREDIT (ERC): A reduction in qualifying emissions, expressed 
in tons per year as rounded down to the nearest one tenth (1/10) of a ton. MCAQD 
issues ERCs for mobile sources as MERCs.  
206 
ENFORCEABLE: Specific measures for assessing compliance with an emissions 
limitation, control, or other requirement established in a permit or in this rule in a 
manner that allows compliance to be readily determined by, but not limited to, an 
inspection of records and reports. 
207 
FLEET MANAGEMENT SYSTEM: A system consisting of location tracking equipment 
and associated software. The system is used to track vehicle miles travelled (VMT) for 
fleet vehicles and is capable of distinguishing travel inside and outside the 
nonattainment area.  
208 
GENERATOR: The owner or operator of a captive fleet of vehicles that has obtained, or 
intends to obtain, a generator permit that has made, or proposes to make, reductions in 
qualifying emissions. 
209 
HISTORIC VEHICLE MILES TRAVELED (HVMT): The annual average VMT from the 
project’s original vehicles that make up the captive fleet. The annual average VMT shall 
be based on the annual actual VMT that occurred within the Phoenix-Mesa ozone 
nonattainment area, from the two preceding calendars years, or two calendar years 
more representative of normal operations within the 5-year period immediately before 
the reduction in qualifying emissions occurs. 
210 
LOAD SHIFTING: Shifting of activity, measured in VMT, of a replaced or retrofitted 
vehicle for which a MERC certificate has been issued to a higher emitting vehicle. 
211 
MERC CERTIFICATE: A document that certifies the issuance of MERCs by MCAQD in 
accordance with this rule, and includes the information specified in 301.3 b.(2). 
212 
MOBILE SOURCE EMISSION REDUCTION CREDIT (MERC): An ERC generated from 
captive fleet vehicles. MERCs have no property rights associated with them. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 74 of 125

213 
MOVES: The latest version of the United States Environmental Protection Agency’s 
(EPA) Motor Vehicle Emission Simulator (MOVES) software. 
214 
NONATTAINMENT AREA: The Phoenix-Mesa ozone nonattainment area as defined in 
40 CFR Part 81.303 for any ozone NAAQS. 
215 
OFFSETS: Reductions in actual emissions required under Rule 240 (Federal Major New 
Source Review (NSR)) of these rules. 
216 
ORIGINAL VEHICLE: A captive fleet vehicle that has been, or will be, replaced or 
retrofitted, to generate qualifying emission reductions. 
217 
PERMANENT: A reduction in qualifying emissions that are enduring for the remaining 
life of the corresponding emissions increase. For the purposes of this rule, an actual 
reduction in qualifying emissions that endure for at least 20 years after the MERC 
certificate is issued. 
218 
QUALIFYING EMISSIONS: NOx or VOC emissions which are included in the current 
ozone attainment plan base year emission inventory or any periodic update to such 
emission inventory, from any on road vehicle when emitted within the nonattainment 
area. 
219 
QUANTIFIABLE: With respect to emissions, including the emissions involved in 
emission trades, capable of being measured or otherwise determined in terms of 
quantity and addressed in terms of character. For the purposes of this rule, 
quantification shall be based on MOVES output emission factors for the baseline 
emissions, the replacement or retrofit vehicle emissions, and the VMT from the original 
vehicle.  
220 
REAL: A reduction in actual emissions previously released into the air resulting from a 
physical change or change to the method of operation by a generator. 
221 
REPLACEMENT OR REPLACED VEHICLE: A vehicle that has, or will replace, an original 
vehicle, used to generate qualified emission reductions, that is certified to the 
applicable federal emission standard. 
222 
RETROFIT OR RETROFITTED VEHICLE: An original vehicle that has, or will have, an 
alteration, that allows the vehicle to operate on a fuel or power source different from the 
fuel or power source for which the vehicle was originally certified; and that is designed, 
constructed, and applied in compliance with the applicable requirements in 40 CFR 85 
and 86. 
223 
SURPLUS: A reduction in qualifying emissions below the emission limitations and 
standards used to comply with any otherwise federally applicable requirements, 
including a required attainment plan, provided that the reduction is not relied upon to 
meet any requirements in the State Implementation Plan (SIP). 
224 
VEHICLE SOURCE TYPE: The specific type of vehicle, as listed in the most recent 
MOVES technical guidance document, including but not limited to: passenger cars and 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 75 of 125

trucks, light commercial trucks, transit buses, other buses, refuse trucks, single unit 
short- and long-haul trucks, and combination short- and long-haul trucks. 
SECTION 300 – STANDARDS 
301 
CERTIFICATION OF QUALIFIED EMISSION REDUCTIONS: 
301.1 MERC Application: 
a. An application to obtain MERCs shall be submitted to the Control Officer on
the form prescribed by the MCAQD and shall include:
(1) Information on the identity, ownership, and location of the generator;
(2) An inventory of the captive fleet, including all information specified in §
504.2, for which a replaced or retrofitted vehicle resulted, or will result, in 
reductions in qualifying emissions; 
(3) A description of the vehicle replacements or retrofits that have resulted, or 
will result, in surplus reductions in qualifying emissions, as well as a 
description of how the reductions in qualifying emissions will be 
permanent; 
(4) Information on the methodology for quantifying the surplus reductions in 
qualifying emissions for each pollutant subject to the application, 
including emissions calculations, documentation of each original vehicle’s 
historic vehicle miles traveled, and how these rates were determined; 
(5) Information on the proper removal or disposal of original vehicles if the 
reductions in qualifying emissions were accomplished, or will be 
accomplished, through vehicle replacement; 
(6) Information on the retrofit conversion process used, or to be used, if the 
reductions in qualifying emissions will be accomplished through vehicle 
retrofit; 
(7) Other information or records necessary to verify that the reductions in 
qualifying emissions qualify as permanent, quantifiable, surplus, federally 
enforceable, and real; 
(8) The actual date or anticipated date the reductions in qualifying emissions, 
occurred, or will occur, as applicable; and 
(9) A signed statement by a responsible official, as defined in Rule 100 
(General Provisions and Definitions) of these rules, verifying the 
truthfulness and accuracy of all information provided in the application. 
301.2 Action on Application:  
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 76 of 125

a. The Control Officer shall review the application for MERCs and evaluate
whether the proposed qualifying emission reductions will result in real,
quantifiable, federally enforceable, permanent, and surplus emission
reductions, and determine whether the MERCs meet the requirements of §
302 for generating MERCs.
b. If the Control Officer determines the requested credits will result in real,
quantifiable, federally enforceable, permanent, and surplus emission
reductions, the generator shall submit an application with the Control Officer
in accordance with the requirements of Rule 210 (Title V Permit Provisions) or
Rule 220 (Non-Title V Permit Provisions) of these rules seeking either a permit
revision or new permit to impose conditions to make the reductions in
qualifying emissions permanent and enforceable.
301.3 Generator Permit and MERC Certificate: The Control Officer, upon completion of 
evaluation of the applications under § 301.2, shall perform the following: 
a. Provide public participation on the Control Officer’s proposed determination
to issue MERCs, and a generator permit or permit revision, per the provisions
in § 407 of Rule 220 of these rules. This requirement applies to all proposed
actions to issue MERCs according to this rule. The proposed determination
shall include the proposed generator permit or permit revision, and the
Control Officer’s underlying analysis for proposing to certify the MERCs.
b. Upon completion of § 301.3 a., if the Control Officer determines the requested
credits meet the requirements of § 301.2 a. and should be certified, then the
Control Officer shall:
(1) Issue either a generator permit or permit revision that incorporates
necessary requirements to make the reductions in qualifying emissions 
permanent and federally enforceable. The generator permit or permit 
revision shall include the following: 
(a) The quantity of VMT used to determine the number of MERCs issued; 
(b) The qualifying emission reduction emission factor for each vehicle 
type and engine model year in the fleet in grams/mile, as calculated 
pursuant to Appendix A, § D; and 
(c) The date by which the qualifying emission reductions are required to 
be implemented. 
(2) Issue a MERC certificate for the total tonnage of MERCs, as rounded down 
to the nearest one tenth (1/10) of a ton, per year of reduction. The MERC 
certificate shall include the following information: MERC certificate 
number, date of issuance, name and address of the generator, description 
of activity that resulted in the qualified emission reductions, and the 
number of MERCs issued. The MERC certificate shall specify that the 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 77 of 125

credits were certified under this rule, and whether the reductions in 
qualifying emissions have been implemented or the date by which the 
reductions are required to be implemented. In addition, the certificate shall 
include the following: 
(a) The quantity of VMT used to determine the number of MERCs issued; 
(b) The qualifying emission reduction emission factor for each vehicle 
type and engine model year in the fleet in grams/mile, as calculated 
pursuant to Appendix A, § D; 
(c) A statement that the new stationary source relying on the emissions 
offsets from a MERC may not commence operation until the emissions 
reductions corresponding to that MERC have actually occurred; and 
(d) A statement that the MERC does not provide any property rights. 
c. If the Control Officer determines that none of the requested MERCs should be
certified, then the applicant will be notified, and no credits will be issued and
neither a generator permit, nor permit revision, will be issued.
301.4 Registration of MERCs in the Arizona Emissions Bank: A MERC Certificate 
(Certified credits) may be registered in the Arizona Emissions Bank but 
registration is not required. See Rule 203 (Emission Reduction Credit (ERC) 
General Requirements) of these rules for procedures regarding registration of 
MERCs in the Arizona Emissions Bank. 
302 
MERC GENERATION: A generator that plans to replace or retrofit all or part of their 
captive fleet to generate qualifying emissions reductions: 
302.1 May apply for issuance of MERCs by meeting the following requirements: 
a. Location: Demonstrate that the captive fleet of vehicles used to generate
MERCs are based and operated within the nonattainment area. MERCs may
only be granted for those reductions generated while operating in the
nonattainment area. An original vehicle’s operation inside the nonattainment
area must be quantifiable.
b. Quantification of Baseline Emissions: The generator shall quantify baseline
emissions for each original vehicle that will be replaced or retrofitted
following the calculation methodology in Appendix A of this rule.
c. Quantification of Emission Reductions:
(1) The generator shall quantify the post project emissions for each original
vehicle using the calculation methodology specified in Appendix A of this 
rule. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 78 of 125

(2) Calculations shall only include surplus reductions and shall not include 
emission reductions created or used under any other emissions trading 
program, emission reductions used to satisfy the State Implementation 
Plan including transportation conformity requirements, or any emissions 
reductions pursuant to a federal consent decree, or state and local 
settlements. 
d. Alternative Calculation Methodology: A generator may use an alternative
calculation methodology to quantify emission reductions upon approval from
the Control Officer and the Administrator. All alternative calculation
methodologies shall be submitted to the Administrator after completion of
the public participation process in § 301.3 a., and shall include any public
comments received and the Control Officer’s response to the public
comments. The Administrator shall be provided 60 days to review the
submittal. Written approval from the Administrator must be obtained prior to
using an alternative calculation methodology.
302.2 Shall comply with the following installation, operating, maintenance, monitoring, 
removal/disposal, replacement, and recordkeeping requirements: 
a. Operation and Maintenance: The generator shall operate and maintain the
replacement and/or retrofitted vehicles in accordance with the
manufacturer’s written instructions, or the maintenance schedule provided by
the manufacturer’s authorized service provider.
b. Fleet Management System:
(1) Fleet Management System Installation, Operation, and Maintenance:
(a) The generator shall install and maintain a fleet management system 
capable of tracking and recording the location and VMT of each 
replaced or retrofitted vehicle for which a MERC certificate is issued. 
The system must differentiate and record travel within and outside of 
the nonattainment area;  
(b) The generator shall operate the fleet management system to monitor 
and record the monthly VMT within the nonattainment area for each 
replaced or retrofitted vehicle for which a MERC certificate is issued; 
and  
(c) The generator shall update, operate and maintain the fleet 
management system in accordance with the manufacturer’s written 
instructions. 
(2) Fleet Management System Exemption: A generator may be exempt from 
compliance with the fleet management system requirements of 302.2 
b.(1) if captive fleet operations for which a MERC certificate is issued 
occur entirely within the nonattainment area. The generator must submit 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 79 of 125

to the Control Officer for approval documentation demonstrating the 
operations occur entirely within the nonattainment area. Such 
documentation may include, but is not limited to, local regulation or 
company policy restricting VMT to within the nonattainment area. In 
addition, the generator must demonstrate how the monthly VMT will be 
monitored and recorded in absence of a fleet management system. 
c. Removal/Disposal of Original Vehicles that were Replaced: The generator
shall remove or dispose of all original vehicles for which a MERC was issued.
Removal shall consist of permanently removing all original vehicles at least
200 miles from the nonattainment area. Disposal shall consist of rendering
the original vehicles permanently disabled and disposed of in a manner that
complies with all applicable local, state, and federal laws. Original vehicles
shall not be relocated to any current ozone nonattainment area, as
designated on the date of MERC issuance. The generator shall maintain
documentation demonstrating proper removal or disposal of all original
vehicles. To demonstrate an original vehicle was properly removed from the
nonattainment area, the documentation shall include a bill of sale, vehicle
registration, or other transfer documentation demonstrating the removed
vehicle complies with the location requirements described above.
d. Subsequent Vehicle Replacements: The replacement or retrofitted vehicles
that were used to acquire MERCs shall only be subsequently replaced with
vehicles certified to the same, or lower, EPA emission standard. This
replacement requirement shall continue for 20 years from the issuance date
of the MERC certificate.
e. Vehicle Retrofit: The generator shall ensure the retrofit vehicle used for
generating MERCs satisfies the exemption from tampering prohibition of
clean alternative fuel conversions through compliance with 40 CFR 85,
Subpart F, and a valid corresponding certificate of conformity or notification
submission to the EPA.
f.
Timing: The generator shall demonstrate that the vehicle replacements or
retrofits, and removal/disposal of original vehicles, occurred prior to either:
(1) The application for MERCs; or
(2) The enforceable date established in the generator permit or permit
revision required by § 301.3 b.(1)(c) that specifies the date by which 
reductions in qualifying emissions must be implemented. 
g. Monitoring and Recordkeeping: Upon issuance of a generator permit or
permit revision under this rule, a generator is responsible for creating and
maintaining records from their captive fleet monitoring as required in:
(1) Section 501 (Recordkeeping and Records Retention);
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 80 of 125

(2) Section 502 (Inspections); 
(3) Section 503 (MERC Generation Monitoring); 
(4) Section 504 (MERC Generation Records); and 
(5) Section 505 (Compliance Demonstration). 
303 
USE OF THE MERC CERTIFICATES  
303.1 General Use Requirements: See Rule 203 (Emission Reduction Credit (ERC) 
General Requirements) of these rules for procedures regarding the use of MERCs 
as offsets to comply with the NSR requirements of Rule 240. 
303.2 Review of MERC Integrity: Prior to issuing a credit user permit, the Control 
Officer shall verify that the MERCs issued in the surrendered MERC certificate 
remain surplus (as defined in this rule) as of the date of permit issuance, and 
shall revise the MERC certificate amount if necessary to maintain surplus 
integrity. Any MERC certificate proposed to be used where the reductions in 
qualifying emissions were not implemented at the time of MERC application shall 
only be used if the MERC certificate states that the emission reductions will be 
implemented on a date prior to the date the new stationary source or 
modification using the credits plans to commence operation of the new source 
or modification.  
303.3 Credit User Commencement of Operation: The credit user shall not commence 
operation of their permitted new source or modification until the generator has 
demonstrated compliance with § 401.1. 
SECTION 400 – ADMINISTRATIVE REQUIREMENTS 
401 OFFSET INTEGRITY RESPONSIBILITIES: 
401.1 Generator Implementation Notification: The generator shall provide written 
notification to the Control Officer and credit user within 48 hours of completing 
implementation of the qualifying emission reductions for which a MERC 
certificate was issued under this rule, and provide documentation demonstrating 
compliance with §§ 302.2 b., 302.2 c., 302.2 e., and 302.2 f.(2), as applicable. 
401.2 Generator Monthly VMT Review Requirements 
a. For each calendar month, the generator shall review the 12-month rolling VMT
as calculated in § 505 to determine if the 12-month rolling VMT achieved by
the generator equals, or exceeds the quantity of VMT specified in their MERC
certificate.
(1) If the 12-month rolling VMT achieved by the generator is equal to or
greater than the quantity of VMT specified in their MERC certificate, the 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 81 of 125

generator shall record the results pursuant to § 505. No further action is 
required.  
(2) If the 12-month rolling VMT achieved by the generator is discovered to be 
less than the quantity of VMT specified in their MERC certificate, the 
generator shall:  
(a) Provide a copy of the data to the Control Officer within 5 business days 
of the date of discovery showing the total 12-month rolling VMT 
achieved; and 
(b) Comply with one of the following: 
(i) DEMONSTRATION OF CONTINUED COMPLIANCE: The generator 
shall provide a demonstration to the Control Officer for approval 
within 30 days of VMT shortfall date of discovery to show that the 
lower VMT was not a result of load shifting and the integrity of the 
MERCs continue. If the demonstration is approved by the Control 
Officer no further action is required. If the demonstration does not 
receive approval, the generator shall notify the credit user, as 
described in § 401.2 a.(2)(b)(ii). 
(ii) CREDIT USER NOTIFICATION: The generator shall notify the credit 
user of the VMT shortfall within 5 business days of the date of 
discovery or within 5 business days of receiving a disapproval of 
the demonstration of compliance from the Control Officer. The 
credit user shall conduct the VMT shortfall evaluation as described 
in § 401.3. 
401.3 Credit User VMT Shortfall Evaluation  
a. If the credit user is notified by a generator, pursuant to § 401.2 a.(2)(b)(ii),
that their 12-month rolling VMT is less than the quantity of VMT specified in
the corresponding MERC certificate relied upon for NSR permit issuance, then
the credit user shall satisfy the requirements of § 401.3 b.
b. Conduct the following calculations and analysis:
(1) Calculate the Emission Reduction Shortfall (ERS) by subtracting the VMT
achieved, as reported by the credit generator pursuant to § 401.2 a.(2), 
from the VMT required in the MERC certificate, and multiplying the 
difference by the applicable qualifying Emission Reduction Emission 
Factor (EREF) specified in the MERC certificate. Where: ERS in tons/yr = 
[(required VMT - achieved VMT) x EREF (in grams/mile)]/907,184.74. 
(2) If the calculated ERS in 401.3 b.(1) is less than 10% of the total MERCs 
issued by the Department to the generator under Section 301.3 b.(2), then 
the credit user or generator shall submit an action plan to the Control 
Officer for approval within 15 days of notification by the generator 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 82 of 125

describing how the  offset emissions shortfall will be remedied no later 
than 3 calendar months after the calendar month that the VMT shortfall 
occurred. This may include documentation demonstrating the credit user’s 
actual emissions for the specific NSR permit issuance that relied on 
MERCs are still sufficiently offset despite the VMT shortfall. A credit user 
or generator that is required to submit a plan by this section must fully 
comply with the plan, which has been submitted but not yet been 
approved, unless notified otherwise by the Control Officer in writing. 
(3) If the calculated ERS in 401.3 b.(1) is 10% or higher of the total MERCs 
issued by the Department to the under Section 301.3 b.(2), or MCAQD 
does not receive an action plan to comply paragraph (2) of this section, or 
MCAQD does not approve the action plan submitted pursuant to 
paragraph (2) of this section, then the credit user shall submit a permit 
application within 90 days of notification by the Control Officer that 
provides an equivalent quantity of reductions as the ERS determined under 
section 401.3 b.(1). This may be accomplished by any combination of the 
following: 
(a) Permanently reducing emissions by revising existing permit emission 
or throughput limits; or 
(b) Providing valid ERCs or MERCs in a quantity equivalent to the ERS 
determined under section 401.3 b.(1). 
(4) A credit user that operates without adequate offsets is in violation of 
these rules. 
402 
ENFORCEMENT AUTHORITY: Nothing herein restricts independent enforcement 
authorities under the Clean Air Act by other parties. 
SECTION 500 – MONITORING AND RECORDS 
501 
RECORDKEEPING AND RECORDS RETENTION: The records and data required by this 
section shall be: 
501.1 Kept on site at all times by the generator in a consistent and complete manner, in 
either electronic or paper format. 
501.2 Made available to the Control Officer no later than five business days upon verbal 
or written request by the Control Officer. 
501.3 Unless otherwise specified, maintained for five years after the record is created. 
501.4 Maintained without falsification. 
501.5 Made available to the Control Officer upon written request by members of the 
public using the County’s public records request process. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 83 of 125

502 
INSPECTIONS: A generator shall provide the Control Officer with access to the 
premises for the purpose of conducting an inspection to verify compliance with this 
rule. An inspection may include, but is not limited to, a review of records and reports. 
503 
MERC GENERATION MONITORING: The generator shall monitor parameters used to 
quantify MERCs beginning no later than issuance of the MERC certificate or the 
enforceable date established in the generator permit or permit revision required by § 
301.3 b.(1). At a minimum, the generator shall monitor the following for each replaced 
or retrofitted vehicle used for obtaining a MERC certificate: 
503.1 VMT within the nonattainment area as determined by the fleet management 
system or alternative method for a generator exempt from the fleet management 
system requirements; 
503.2 Any other parameter used to make the MERCs quantifiable, such as idling speed, 
idling emissions, or fuel use rate. 
504 
MERC GENERATION RECORDS: A generator shall maintain the following records for 
each replacement or retrofitted vehicle for which a MERC certificate was issued: 
504.1 MERC Documentation: All records submitted with the application, 
documentation that the original vehicle or original vehicle engine was properly 
removed and/or destroyed, as required by § 302.2 c., and documentation 
demonstrating the HVMT for each original vehicle that occurred within the 
nonattainment area. These records shall be maintained for at least five years 
after the use of the MERCs to obtain a NSR permit, regardless of any defenses 
under any federal or state statute of limitations. 
504.2 Replaced or Retrofitted Vehicle Inventory Records: A detailed inventory of each 
replaced or retrofitted vehicle used to generate MERCs shall include all of the 
following information and shall be reviewed and updated on a monthly basis: 
a. For each replaced or retrofitted vehicle:
(1) The vehicle manufacturer.
(2) The model number.
(3) The model year.
(4) The vehicle source type.
(5) Serial number.
(6) Fuel type.
b. The date each replaced or retrofitted vehicle was:
(1) Added to the inventory and began operation.
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 84 of 125

(2) Removed from the inventory. 
c. After the initial project, for each vehicle added to the inventory:
(1) Identify the vehicle removed in its place.
(2) The generator must document that the replacement vehicle is certified to
equivalent or lower standards than the vehicle or engine used to generate 
MERCs. 
504.3 Operational Records: The following operational records shall be maintained on a 
monthly basis upon issuance of the MERC certificate or when the generator 
notifies the MCAQD that the project has been completed, as applicable: 
a. A description of all maintenance and repair activities, current vehicle mileage,
date the activity occurred, and any corrective actions performed.
b. The calendar month VMT that occurred within the nonattainment area for
each vehicle as recorded by the fleet management system or alternative
method for a generator exempt from the fleet management system
requirements. The VMT records shall be aggregated by the vehicle source
type.
c. Quarterly records demonstrating that all fleet management system software
and maps have been updated to the most current version.
d. For any generator operating under the fleet management exemption in 302.2
b.(2), a record of any VMT outside the nonattainment area.
e. Summary of any other monitoring required by § 503 of this rule.
504.4 Vehicle Retrofit Records: The generator shall maintain a record for each 
retrofitted vehicle that was used to generate MERCs that demonstrates 
exemption from tampering prohibition of clean alternative fuel conversions by 
compliance with 40 CFR 85, Subpart F. This includes the applicable valid 
certificate of conformity or notification submission to the EPA. 
504.5 Annual Report: The generator shall submit an annual report to the Control Officer 
summarizing the captive fleet’s operation and compliance with § 302.2 b. for the 
previous calendar year, within 60 days after December 31 of each calendar year. 
The report shall include the following: a statement attesting that any replaced 
original vehicle is not a part of any other captive fleet owned or operated by the 
generator within 200 miles of the nonattainment area and how this was verified, 
the current captive fleet inventory as specified by § 504.2, the VMT by the fleet of 
vehicles used to generate MERCs within the nonattainment area during the 
previous calendar year. Additionally, any generator that operates under the fleet 
management system exemption in Section 302.2 b.(2) must provide a statement 
attesting that operations continue to occur entirely within the nonattainment area 
per the documentation provided in Section 302.2 b.(2). 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 85 of 125

505 
COMPLIANCE DEMONSTRATION: Within 30 days of the end of each month, the 
generator shall: 
505.1 Record the amount of VMT within the nonattainment area for each replacement 
or retrofitted vehicle during the preceding month and record the VMT sum for all 
replacement or retrofitted vehicles, aggregated by vehicle source type. 
505.2 Calculate and record the 12-month rolling total of VMT within the nonattainment 
area. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 86 of 125

Rule 205 APPENDIX A 
CALCULATIONS FOR DETERMINING EMISSION REDUCTIONS FROM 
VEHICLE REPLACEMENT OR RETROFIT PROJECTS 
A. Baseline Emissions (g/year) = HVMT (miles/year) × Baseline Pollutant Emission 
Factor (g/mile) 
1. Where g is grams of pollutant emitted.
2. Where HVMT as defined in § 209.
3. Where the Baseline Pollutant Emissions Factor, in g/mile, is determined by
running the latest version of MOVES. The data points needed to run the MOVES
model includes, but is not limited to, the following:
(a) Original vehicle fuel type,
(b) Original vehicle engine model year,
(c) Aggregated HVMT per vehicle source type, and
(d) The vehicle type of the fleet vehicles.
4. Based on this input, the MOVES model will output the total emissions from the
baseline fleet based on an original vehicle engine model year (g/year). To obtain
tons/yr, the regulatory quantity, multiply by 1.1 x 10-6. To determine a g/mile
emission factor, this emission total shall be divided by the input HVMT per
vehicle type (miles/year).
B. Post Project Emissions (g/year) = HVMT (miles/year) × Post-Project Pollutant 
Emission Factor (g/mile) 
1. Where g is grams of pollutant.
2. Where HVMT as defined in § 209.
3. Where the Post Project Pollutant Emissions Factor, in g/mile, is determined by
running the latest version of MOVES. The data points needed to run the MOVES
model includes, but is not limited to, the following, as applicable:
(a) Replacement or retrofit vehicle fuel type,
(b) Replacement or retrofit vehicle engine model year,
(c) Aggregated HVMT per vehicle type, and
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 87 of 125

(d) The vehicle type of the fleet vehicles. 
For a retrofitted vehicle, the vehicle engine model year corresponds to the year 
the emission reductions are generated by retrofitting the original vehicle.  
For a replacement vehicle, the replacement vehicle engine model year 
corresponds to the model year of the replacement vehicle. 
4. Based on this input, the MOVES model will output the total emissions from the
replacement or retrofitted fleet based on a vehicle engine model year (g/year). To
obtain tons/yr, the regulatory quantity, multiply by 1.1 x 10-6. To determine a
g/mile emission factor, this emission total shall be divided by the input HVMT per
vehicle type (miles/year).
C. The amount of eligible emission reduction credits for each vehicle is calculated by 
subtracting Post Project Emissions from Baseline Emissions. 
D. The qualifying emission reduction emission factor for each vehicle type and engine 
model year in the fleet is calculated by subtracting the Post Project Pollutant 
Emissions Factor from the Baseline Pollutant Emissions Factor, grams/mile. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 88 of 125

1 
MARICOPA COUNTY BOARD OF HEALTH 
MEETING MINUTES 
Monday, January 24, 2022, at 3:00 PM 
Virtual Meeting due to COVID-19 and social distancing guidelines 
President MacMillan called the meeting to order at 3:02 p.m. 
ROLL CALL:         
Members Present:         
Chairman Bill Gates 
Debra Baldauff  
Don Cassano 
 
Paul Stander 
Paula Banahan 
Robert MacMillan  
Scott Celley 
Members Absent: Kristen Acton        
Ex-Officio: Marcy Flanagan 
1.
CALL TO ORDER
President MacMillan 
A. Roll Call 
B. Call to the Public 
President MacMillan called the meeting to order at 3:02pm, addressing the public advising all how to use the 
chat box to comment or add any questions for the agenda items. There were no requests known to speak at this 
time; all were informed that they would have the opportunity to type questions using the chat box, which will be 
acknowledged during and or after the meeting accordingly. 
DISCUSSION/ACTION ITEMS: 
2.
Approval of Minutes
President MacMillan 
President MacMillan asked for a motion to approve the minutes from the Board of Health (BOH) meeting held 
on October 25, 2021.  A motion was made by Mr. Cassano to approve the BOH minutes as presented. Mr. 
Celley seconded the motion. The motion passed unanimously.  
3.
Public Health Update – FY 2022 Quarter Budget Status Report
Scot Pitcairn 
Mr. Pitcairn provided an update for the Public Health Fiscal Year 2022 Budget Status Report. A memo was 
provided outlining the updates for the below listed funds. 
•
Fund 100 – General Fund
Mr. Pitcairn noted that the memo for the fund 100 should indicate that the department received positions for 
FY22 not FY23. There were no questions pertaining to the general fund 100. 
Return to list of attachments
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 89 of 125

2 
•
Fund 265 –Public Health Fee Fund
The forecast show that the department was just coming in under budget and the department will keep an eye 
on the fund over the next couple of months before submitting an adjustment request. The Refugee fund is a 
state expense, not federal. When Refugees enter the country, they are placed on an emergency AHCCCS, which 
is how individuals are provided coverage as far as the Federal government because that’s reimbursed. Once 
individuals are put on emergency AHCCCS, Public Health bills this out using the AHCCCS Program through the 
insurance providers. If there is a program and AHCCCS does not pay, then yes, the federal government does 
reimburse, after the denial of the claim.  Reimbursements were previously from the Refugee Medical Assistance 
Program, (the Federal Program), and then it was pushed over to AHCCCS in certain cases, now it’s almost 100 
percent from the AHCCCS reimbursement.  There were no additional questions pertaining to fund 265.   
•
Fund 296 – State & Local Recovery Funds/American Rescue Plan Act (ARPA)
A share of fund 296 supports the finance and rent infrastructure needs of the rest of the COVID related grants. 
Other major “buckets” of funding include COVID isolation housing (hotel), technology needs for Epidemiology 
and Public Health, PPE supplies, and an additional regional public health facility in Goodyear, recently 
purchased. There were no questions pertaining to fund 296.  
•
Fund 532 - Grant Fund
The COVID-related grants are direct federal, or federal fundings passed through the state, and fall into three 
categories: 1) Epidemiology and Disease Investigations; 2) Immunization; and 3) Health Equity and Disparities. 
Spending for many of the non-COVID grants is still recovering from the effects of the pandemic. An example was 
provided such as the Dental Sealant grant. The biggest challenge filling positions, recruitment has still provided 
applicants for most of the positions, however it’s possible that the number of applicants and qualified applicants 
are affecting recruitment. The labor rate for personnel has increased throughout the nation and one concern is 
that a lot of the standard operational grants are flat-funded. Human Resources (HR) has done several market 
studies increasing compensation to help with recruitment. As increases come in, they are struggling to exercise 
those compensation increases because it doesn’t fit within their funding. This is not a good thing or a bad thing, 
it’s simply something that impacts recruiting and grants will need to be addressed in order to have their service 
levels maintained at the same rate, they’re going to have to increase their compensation and reimbursement 
rates to Public Health to coincide with the increases. The department is struggling with the recruiting pool, as 
well as the entire nation. The department has loads of funding coming, and yes, some of the grants over the 
years have been level funded and obviously, cost salary, cost have increased over time, so that becomes quite a 
squeeze on some of the grants. During the end of a three or five-year cycle, the grant contract may be adjusted 
for pay increases. A few have already received some adjustment with compensation and reimbursement rates, 
mid contract. The department is expecting changes at the end of the contracts for next year. There were no 
additional questions pertaining to fund 532. 
(refer to memo and report summary attached to meeting agenda) 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 90 of 125

3 
4.
Environmental Services Department FY 2022 Quarter Budget Status Report
Ryan Hautzinger 
Mr. Hautzinger provided the Board with an update of the Environmental Services Department Fiscal Year 2022 
Budget Status Report. A memo was provided outlining the updates for the below listed funds. Environmental 
Services has relocated to the main county building located at 301 West Jefferson on the 5th floor.  
•
Fund 100 - County General Fund
Mr. Hautzinger reported on Fund 100 as outlined in the Environmental Departments report. There were no 
questions pertaining to fund 100.  
•
Fund 290 – Environmental Tire Fund
Fund 290 FY 22 trend has reversed through the second quarter of FY 22 which was due to higher second quarter 
revenues distributed from the State of Arizona through the Tire disposal tax.  The memo provided outlines the 
updates for the tire funds. The theory is that the state distributed the revenue as a result of higher disbursing 
because of a lag. Although not confirmed, the department is trying to get more communication with the state to 
see these trends out. The Quarter 3 report will hopefully provide more information. There were no legislation 
changes. There were no additional questions pertaining to fund 290. 
•
Fund 506 – Environmental Fee Fund
As predicted in the quarter 1 report, Fund 506 was revenue was much stronger these past three months in the 
2nd quarter and created a positive variance in the fund. There were no additional questions pertaining to fund 
506. 
(refer to memo and report summary attached to meeting agenda) 
A. Air Quality Department  
Greg Verkamp 
Kimberly Butler 
Mr. Verkamp directed the board to the department’s memo and agenda action item requesting to approve the 
initiation of regulatory change for rule 205 - AQ-2021-004 titled “Emission Offsets Generated by Voluntary Mobile 
Source Emission Reduction Credits”, which was previously distributed to the board for their review. The rule 
requires action to be recorded by the members of the board.  
Approve initiation of regulatory change for the following rule 205 – AQ-2021-004: 
AQ-2021-004 
Rule 205 (Emission Offsets Generated by Voluntary Mobile Source Emission Reduction Credits) 
Maricopa County is currently designated as a nonattainment area for both the 2008 and the 2015 ozone 
National Ambient Air Quality Standard. In ozone nonattainment areas, the Clean Air Act requires owners 
and operators proposing to construct a new major source or make a major modification to obtain 
emission offsets before the project may commence. Currently, insufficient emission reduction credits 
exist in the Arizona Emissions Bank for large businesses to use as emission offsets. The purpose of this 
rulemaking is to create a new economic development rule which will provide a mechanism for the 
creation of more emission reduction credits, specifically mobile source emission reduction credits 
(MERCs), for use as emission offsets. 
The purpose of the rulemaking is to create a new economic development rule, which will provide a mechanism 
for the creation of more emission reduction credits, specifically, what are called mobile source emission reduction 
credits, or MERCs as people often refer to them, for use as emission offsets. On January 10th a stakeholder 
workshop was held to discuss the proposed rule. The department is in the process of evaluating the comments 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 91 of 125

4 
that were received during the workshop. In addition, the department is also in the process of discussing the rule 
with the EPA to obtain their feedback as they move forward in the rulemaking process. Including the EPA in the 
process is crucial to ultimately getting approval of rule 205 from the EPA. Air Quality intends to host at least one 
more workshop after further discussions with the EPA and will eventually return before the board to request a 
recommendation to the Board of Supervisors. Air quality is requesting for the board of health’s approval to initiate 
the rulemaking. 
It was noted that the record retention for emissions date back for a five-year period. In order to calculate the 
baseline emissions, the two most recent and representative years are what’s considered a normal operating 
condition and you can go back as far as five years. Using the example of individual plants keeping a 10-year record 
keeping, the board suggested during times of economic downturn, the five-year record keeping is not the best. 
Air Quality will evaluate the board’s suggestion and report back to the board on its findings. President Macmillan 
questioned if there was a mobile source regarding emission credits, or if it was something new? Mr. Verkamp 
referred to Rule 204, mobile source, like on-site equipment, there wasn’t on-road, it was all off road, like baggage 
handlers at the airport as an example. Mobile source is new, and the department is looking at on-road vehicles, 
such as this rule, which is going to focus on fleets of vehicles, captive fleets.  A discussion was had pertaining to 
the city fleets that operate within the non-attainment area or the delivery companies, (UPS, FedEx) that have 
these fleets of vehicles and decide to modify them to be more efficient vehicles and pollute less, which is the focus 
of those types of fleet vehicle.  A comment was had at the workshop regarding including credit for VOC or PM 2.5 
reductions, the department is looking at modifying the rule to allow for credit for other pollutants beyond NOx. 
The department reviewed two rules and showed there wasn’t a lot or any use of them. A discussion about old 
fleets not having a GPS was had, and a question about whether a statement like an affidavit from mileage records 
can legitimize area use being in the ozone non-attainment area, the credits have to be justified as being taken. 
This issue came up during a workshop, the idea that does every fleet vehicle have to have a GPS installed, the 
department is in the process of reaching out to that stakeholder to see what they propose as alternatives. But, as 
far as recordkeeping and the GPS, the mileage, in order for the EPA to review and approve, they have to determine 
that the MERCs are enforceable. It was also noted that the new vehicles must be used the same way the generator 
was using the replaced vehicles. The department would need to get it approved locally; however, it won’t be 
usable until the EPA approves it. There were no additional comments had. 
President MacMillan asked if anyone wanted to make a motion to approve initiation of regulatory change for 
Rule 205 - AQ-2021-004. Mr. Celley made a motion to approve Rule 205 and Mr. Cassano seconded the 
motion. All were in favor. 
5.
Fee Waiver Applications Fifteen (15) permit fee waiver approval requests
Robert Stratman 
A. 01-24-22 Fee Waiver Staff Report.pdf  
B. 01-24-22 Fee Waiver Application Summary Sheet.pdf  
The department received 15 Permit Fee Waiver applications and staff determined that all met the criteria 
outlined in the Environmental Health Code. The criteria - an operator of a charitable non-profit establishment, 
which operates predominantly for the poor distressed or underprivileged that may apply to the Board of Health 
for the waiver of a permit. A waiver may be granted only if the operator maintains a current 501 (c)3 tax-exempt 
status and demonstrates that the payment of the said fee will cause a financial hardship. In addition, a waiver of 
fees associated with the administering and issuance of a food employee certificate in compliance with Arizona 
revised statute, Article 41-1080, may be granted to a current student enrolled in a K through 12 culinary arts 
school program or similar curriculum based programs requiring food employee certificates. The sponsoring 
school district must demonstrate to the board of health that payment of said fees will cause financial hardship.  
All 15 fee waiver applications reviewed this quarter appear to meet the criteria. The department is asking for the 
board’s approval of the 15 fee waiver application summary sheet labeled P1-P13 and C1 through C2. The 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 92 of 125

5 
department has two different application types that are reviewed. 1) Permit side, and yes, schools who do serve 
food to students are required to get a permit from the department, 2) Classes K-12 Culinary Arts program, those 
are not required, if it’s done as a part of classrooms, typically to obtain a permit. However, some of the services 
they provide help students obtain a Food Handling Certificate, a lot of the programs will prepare students for 
work. Students working in a food establishment must have a certificate, schools providing the programs, and 
coordinating with the department to provide the training to then subsequent certificates to meet the criteria. 
It’s not the students being served; it’s the student in the program who would need to meet the criteria. Any 
school that can meet the criteria would qualify for the fee waiver, and it’s not that the students they’re serving 
are the underprivileged or poor; it’s the students that are obtaining the certificates that fall into that category 
that are receiving the food training certificates. Most schools don’t have a 501(C)3, so it’s not expected that all 
schools within the county would apply or meet the criteria, and that’s where the fee waiver comments relate to 
the permits. The fee waiver for the certificates is related to the students in those classes receiving that training. 
So, there’s a potential differentiation there between who is being served and what the training is for. Therefore, 
it’s not expected that there would be a considerable increase in fee waivers because not every school in the 
county would meet the fee waiver criteria. 
(memo and report summary attached to meeting agenda) 
President MacMillan asked if there was a motion to approve the 15 fee waiver applications presented as P1 
through P13 and C1-C2. A motion was made by Mr. Celley to approve the fee waiver applications labeled as 
P1 through P13, and C1-C2. The motion was seconded by Mr. Cassano. All were in favor, the motion carried. 
Discussion Items 
6.
Public Health Report
Marcy Flanagan 
A. Human Resources 
B. Communications 
C. Infrastructure 
D. Strategic Planning 
E. Programs 
F. Disease Update 
G. Health Status/Community Health Needs Assessment (CHNA) 
Lilliana Cardenas 
H. Future Topics 
Ms. Flanagan provided the board with the COVID-19 case updates for Maricopa County. 
COVID-19 Update 
•
Maricopa County case count 10,482 as of last week, the county has had over 16,000 cases in just one
day
•
Maricopa County hit over 1 million cases,
•
Maricopa County related Covid deaths 14,304 (increased with surge of the Omicron cases)
•
Hospital Positive patients’ cases trends upward, but not as high as last winter
•
Hospital cases are not as high as last year, possibly because there is a vaccine available now, which has
helped, also Omicron isn’t having severe outcomes as previous training, specifically, the Delta variant.
The case count usually lags about two weeks behind the county’s case count. The hope is that the
hospitalizations level off and start trending down as well.
•
Hoping that Maricopa County has reached our peak and cases begin to trend downward.
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 93 of 125

6 
•
Rate of transmission per 100,000 residents, benchmark for January 2nd through the 8th was 1775 per
100,000, the following week increased to 2008 per 100,000 which put the county community spread
rate twenty times higher, once Omicron took over the case rates exploded.
In review of the last few weeks of December, first weeks of January shows that the county was up as high as 
36% of test positive cases, which indicates that there is not enough testing in the county. Rapid over the counter 
test are hard to come by, same day appointments have become difficult for most to get into a provider office for 
testing. 
(A more detailed report is attached to the agenda) 
Children and Schools 
One in six cases are among children here in Maricopa County. When the Delta variant began in April. And these 
were our percent of Kobe cases among children less than 18. It really increased, when school went back in 
session, you saw in August, you see that it's come down a little bit. We know that part of the reason it came 
down November, December, is they had their fall, and winter breaks happening. So, it has started to go up 
slightly. However, we're not to where we were in August 2020 when school went back in session, which is a 
good thing, mainly due to with the vaccine now being available for all school aged children, which happened at 
the beginning of December.  
•
Children account for 7% of hospitalizations
•
Newly identified school outbreaks continued to rise
•
As of 1/19/22 - there were 363 ongoing school outbreaks
•
The county is now under the 363 cases reported
(A more detailed report is attached to the agenda) 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 94 of 125

7 
NEW CDC Guidance 
Up To Date on COVID Vaccines 
The message to get vaccinated and stay up to date was encouraged. 
Up to date – means a person has received all recommended COVID-19 vaccines, including any booster 
dose(s) when eligible. 
Fully vaccinated – means a person has received their primary series of COVID-19 vaccines. 
Ms. Flanagan continued to report on new isolation guidance, quarantine: Not Up to date on COVID vaccines, Up 
to date on COVID vaccines and Quarantine: Exposed & Confirmed COVID as shown below. (Full presentation is 
attached to the agenda) 
COVID 
Vaccine
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 95 of 125

8 
New Isolation Guidance 
Quarantine: Not Up To Date on COVID Vaccines 
New IsolaƟon Guidance
QuaranƟne: Not Up-To-Date on COVID 
vaccines
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 96 of 125

9 
Quarantine: Up To Date on COVID Vaccines 
Quarantine: Exposed & Confirmed COVID 
Contact the Public Health office should anyone need additional information or visit the 
www.maricopa.gov/covid website for more information. 
QuaranƟne: Up-To-Date on COVID vaccines
QuaranƟne: Exposed & Confirmed COVID
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 97 of 125

10 
New Federal Initiatives 
•
At-home test kits
o
The White House started the “At-home test kit program” with the goal of providing free rapid
at-home test kits to every household in America
o
Individuals can go to: www.COVIDTests.gov to order their kits
o
Test kits usually ship 7-12 days after ordering
•
Free N95 masks for public
o
The Biden Administration is making 400 million N95 masks available to Americans for free.
o
Masks will come from the Strategic National Stockpile & will be available for the public to pick
up at tens of thousands of local pharmacies and community health center sites across the
country.
o
The Administration is starting to ship masks at the end of this week, and masks will start to be
available at pharmacies and community health centers late next week. The program will be fully
up and running by early February.
o
This is the largest deployment of personal protective equipment in U.S. history.
•
Important message (Masks)
o
Any mask is better than no mask.
o
CDC continues to recommend that you wear the most protective mask you can that fits well and
that you will wear consistently.
o
Masks and respirators are effective at reducing transmission when worn consistently and
correctly.
o
Some masks and respirators offer higher levels of protection than others, and some may be
harder to tolerate or wear consistently than others. It is most important to wear a well-fitted
mask or respirator correctly that is comfortable for you and that provides good protection.
o
While all masks and respirators provide some level of protection, properly fitted respirators
provide the highest level of protection.
Ms. Flanagan responded to questions at the conclusion of the presentation. 
Well-fiƩed respirators provide
the best protecƟon.
Wear the highest quality
respirator or mask that has
the correct fit, protecƟon,
and comfort for you.
High quality respirators are
important if you are older,
immunocompromised, not
up-to-date on your COVID-19
vaccinaƟons, or in higher risk
situaƟons.
Mask RecommendaƟons
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 98 of 125

11 
•
What were the relative percentages among patients hospitalized?
o
The county is seeing that upwards of 80, and more times, not locally. What they've heard
from the CEOs or CMOS is that they're seeing 90% of the hospitalizations or more are
unvaccinated individuals.  The vast majority of hospitalized cases are in those who are
unvaccinated.
•
What were the most up to date numbers on the percentages of those vaccinated in Maricopa
County using those definitions presented?
•
What the county is working on now is trying to extrapolate that data from the AHCCCS System,
which is the statewide system that tracks vaccines, unfortunately, what happened early on is the
weight tracking was done for covert 19 vaccine. It wasn't really categorized in these series and
booster and knowing what means up to date for some individuals as opposed to others for
instance; if someone is immunocompromised, they have recommended more doses for those
individuals. So, at this point, public health hasn't been able to separate the data to show the up to
date versus fully vaccinated.
The numbers of individuals who are fully vaccinated and Maricopa County were right around that, 
55%, it’s unknown if that number is based on fully vaccinated. Public Health doesn't know how 
much of that 52 or 55% is up to date, meaning that they have their boosters as well. The public 
health team is really trying to work with the ADA just to make sure that they can have accurate data 
on that, but unfortunately there is no way to currently with the way numbers are pulled, the data and 
information from the Arizona DHS to differentiate between the two, but the department is working 
on that.  
•
What is the quarantine within congregate settings, are the recommendations for jails and group
homes?
o
The information is different, the presentation relates to the general public. Long-term care
facilities and assisted living retirement communities, share congregate housing. There are
other considerations, and that's all available on the county’s website as well as the CDC
website, especially in those situations, because it's typically considered an outbreak situation
when cases happen in those settings. It's not just an exposure, like a community exposure or
family exposure. You're typically having an outbreak, and so those are treated differently.
•
The recommendation is for everyone to be tested when a family member in close contact tests positive.
•
Maricopa county has seen more infection in children than early on in the pandemic when another
household member was positive
•
The bigger contributing factor is that there is more spread happening in children
•
Omicron has affected more children, then other variants at the beginning of COVID
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 99 of 125

12 
Community Health Needs Assessment (CHNA) 
Lily Cardenas 
Public health conducts a community health needs assessment (CHNA) every 3-5 years. Maricopa 
County commonly conducts this report every 3 years. Ms. Cardenas provided the purpose of the CHNA 
and continue to present the information using the presentation slides attached to the agenda emphasizing 
how COVID-19 impacted the data. 
An outline of the presentation reported on consisted of: 
•
Collaboration for Health Improvement
•
CHNA Partnership Process
•
COVID-19 Impact Survey
•
Focus groups and Summary of Participants
•
Impact on Mental, Physical and Behavioral Health
•
Primary barriers to accessing healthcare in communities
•
Impact on Addition/Substance Abuse/ Food Insecurity
•
Vaccine options and Qualitative Analysis
Purpose of CHNA
• MAPP: Mobilizing for Action through
Planning and Partnership
• Comprehensive data collection of a
community to identify strengths,
needs, and health priorities.
• Establishes the priorities for the
development of a Community Health
Improvement Plan (CHIP).
• Required of all tax -exempt hospitals
as part of the Patient Protection and
Affordable Care Act.
• Influences allocation of funds and
resources for health improvement
• Conducted every 3 years
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 100 of 125

13 
During the focus groups conversations provided that there were a lot of concerns surrounding the vaccine. 
•
Long term side effects
•
Fertility, brushed vaccine development
•
FDA approval
•
Vaccine cost
There was a lot of confusion in the community, especially some of the harder to reach communities, that 
they had to pay for the vaccine. Some doctors, offices, clinics, and places that were providing the 
vaccine, unfortunately, hadn't ironed out all the bugs and billing, and so sometimes people would 
receive a bill, and then they would tell their friends and their neighbors, how they were charged when it 
was a mistake. And that's not what was supposed to be happening. There was often some confusion 
there. The group saw a lot of folks that just didn't perceive themselves to be high risk. At this point, most 
everyone has heard a story of someone who was surprised they got COVID, and they died, comments 
usually followed that “they always seem so healthy, we never thought”. Unfortunately, that has been 
something that has affected so many people, and then when asked about how people were getting 
information. Doctors and primary care providers still are a strong influence because most people have 
trust again in their doctors and primary care faith and faith leaders, and community leaders and elders.  
The results of the community data collection efforts, can be accessed on the website: 
www.maricopahealthmatters.org 
CHNA Data and Profiles
MCDPH is committed to sharing the 
results of community data collection 
efforts to improve public health 
strategies and support our community 
partners, visit: 
www.maricopahealthmatters.org
• Current CHNA and CHIP Reports
• Past CHNA and CHIP Reports
• Regional & City Profiles
• Synapse Hospital & Healthcare
Partnership
• Health Improvement Partnership of
Maricopa County (HIPMC)
• MySidewalkData Dashboard
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 101 of 125

14 
MCDPH created snapshots for each of our five regions as well as county wide. Several cities were 
included that also were able to collect sufficient data to have their own profile. This is a huge benefit to 
the city. The data is a rich source of information of the community and also uses to leverage. When they 
write grants or submit proposals for any type of project, they really can show this. So, the department 
receives a lot of buy in from the community, organizations, hospitals and municipalities because of this 
work. 
Next Steps… 
Data driven funding & resource allocation. 
•
RFP – Regional Funding to address Health Disparities, focus on priority issues by region up to $12.5
million
•
RFP – Countywide Funding to address Health Disparities, focused on Access to Healthcare up to $1.5
million
•
Establish Community Advisory Boards per region to develop and inform Regional Community Health
Improvement Plans.
MCDPH received 26.5 million dollars, from the Center for Disease Control to address health disparities. 
The department is in the process of open request for proposals to provide regional funding to address 
health disparities. Public health is allocating 12.5 million to be distributed within the five regions 
approximately 2.5 million per region and 1.5 million for county-wide initiatives that address access to 
health care, the regional ones are health disparities. So those that get funded are going to come together 
and create these regional community advisory boards to really get more information on the community, 
and really work with them to develop action plans, and really help public health get back on track. The 
department expressed being excited that this work is really leading to some educated data, driven 
decisions, funding and resource allocation ends. Ms. Cardenas referred the board to the flyer distributed 
to the public. Community members were involved in the pre-conference bids asking various questions. 
There were almost 140 participants on the call expressing interest in applying for funding.  
Mental health was identified as a big issue considering that most individuals had changes in their job or 
employment status. Risk factors like obesity has been a topic of concern during the pandemic. The 
department has seen some short-term negative impact from obesity and the ability to try to reverse those 
trends.  At the conclusion of the CHNA report, the board expressed their appreciation for all the work 
that goes into producing the data presented and that it provided a broader view of the community needs. 
Announcements and Current Events 
President/ 
Board Members 
None 
Adjournment 
President MacMillan 
There being no further business, Mr. Cassano made a motion to adjourn the meeting and Ms. Balduff seconded 
the motion. The motion passed unanimously. The meeting was adjourned at 5:00 p.m. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 102 of 125

1 
MARICOPA COUNTY BOARD OF HEALTH 
MEETING MINUTES 
Monday, January 23, 2023, at 3:00 PM 
In Person & Virtual Meeting  
President MacMillan called the meeting to order at 3:02 p.m. 
ROLL CALL:          
Members Present:           
Debra Baldauff  
Don Cassano 
(via phone) 
Matthew Farber 
Paul Stander (via phone) 
Paula Banahan 
Robert MacMillan  
Members Absent: 
Scott Celley 
Supervisor Bill Gates 
Kristen Acton        
Ex-Officio: Marcy Flanagan 
1.
CALL TO ORDER
President MacMillan 
A. Roll Call 
B. Call to the Public 
Addressing the public, President MacMillan advised all how to use the chat box to comment or add any 
questions for the agenda items. Ms. Sampler informed all that there were no requests known to speak at this 
time; all were told that they would have the opportunity to type questions using the chat box, which will be 
acknowledged during and or after the meeting accordingly. 
DISCUSSION/ACTION ITEMS: 
2.
Approval of Minutes
President MacMillan 
President MacMillan asked if there was a motion to approve the minutes from the Board of Health (BOH) 
meeting held on October 24, 2022. Dr. Farber motioned to approve the BOH minutes as presented and 
seconded by Mr. Cassano. The motion passed unanimously.  
3.
Public Health Update
Scot Pitcairn 
2nd Quarter Update - Fiscal Year 2023 Budget Status Report
Mr. Pitcairn provided an update for the Public Health FY23 Quarter 2 Budget Status Report for the funds listed 
below. The finance memo is attached to the agenda outlining the updates for all funds reported.  
Return to list of attachments
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 103 of 125

2 
•
Fund 100 – General Fund
•
Fund 265 –Public Health Fee Fund
•
Fund 293 – Justice Reinvestment Fund
•
Fund 296 – State & Local Recovery Funds/American Rescue Plan Act (ARPA)
The board requested additional information for fund 296, Ms. Lee Ann Bohn provided a link to reference  
COVID-19 American Rescue Plan Act Funds | Maricopa County, AZ. 
•
Fund 297- Opioid Settlement Fund
•
Fund 532 - Grant Fund
The total amount for the new Workforce Infrastructure grant from the CDC is approximately $38 million upfront 
one-time funding to be used over a five-year period and then $1.7 million annually for each of the next five 
years. According to Ms. Flanagan, the Infrastructure Grant is the first time that the Federal Government has 
pledged this amount of funding for public health infrastructure. The purpose is to reinforce the staff that local 
public health hired during COVID, so when the next pandemic occurs, public health will avoid being behind as 
was seen nationally. Most of the health departments are trying to catch up so that they are prepared to do 
contact tracing, case investigation, and other types of work needed. Much of the funding is going to continue 
employing staff and ensure that public health has a stable minimum infrastructure in the department to respond 
to emergencies and continue to be an accredited health department to have comprehensive business and 
finance, grant management kind of department. A lot of the funds are going toward that purpose as well as 
staffing for additional clinics purchased with the ARPA monies. Those positions are billable activities that occur 
in the clinic. The CDC advises that the 1.7 million is not only for the five years the health department was 
rewarded, but the funds will be a part of their permanent budget from the federal government.  
A discussion was had about obtaining qualified candidates. Should the department present an offer to a 
candidate for which they decline the offer, the department would need to start the recruitment process over 
again. This has caused a change in the pay scale midyear. The county approved a 10 percent pay rate, which 
made a difference.  
There were no additional questions for any of the funds reported. 
Environmental Services 
Sylvie Donaldson 
2nd Quarter Update - Fiscal Year 2023 Budget Status Report  
Ms. Donaldson presented the Board with the Environmental Services FY23 Quarter 2 Budget Status Report for 
the funds listed below. The finance memo is attached to the agenda outlining the updates for all funds reported. 
•
Fund 100 - County General Fund
•
Fund 290 – Environmental Tire Fund
•
Fund 506 – Environmental Fee Fund
The department has also seen challenges with its recruitment due to wages; however, the large increase 
approved by the Board of Supervisors brought some relief to the process. There is a job fair coming up, which 
the department is hoping will help with recruitment. The board responded that various industries are still facing 
challenges even with the increase in wages and are not having a lot of success nationally.  There were no 
additional questions for any of the funds reported.  
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 104 of 125

3 
4. Environmental Services Dept. Fee Waiver Applications –
Robert Stratman 
Request for Board of Health approval of twelve (12) fee waiver applicants 
This quarter, the department reviewed twelve (12) fee waiver applications. Of the applications reviewed, staff 
determined that all meet the criteria outlined in the Maricopa County Environmental Health Code.  
As a reminder, only an operator of a charitable nonprofit establishment that operates to provide relief 
predominantly for the poor, distressed, or underprivileged may apply to the Board of Health for a waiver of a 
permit fee. A waiver of a permit fee may be granted only to the operator of an establishment that maintains a 
current 501(c)(3) tax-exempt designation from the Internal Revenue Service and who demonstrates to the Board 
of Health that payment of said fee will cause financial hardship. In addition, a waiver of fees associated with the 
administering and issuance of a food employee certificate (in compliance with A.R.S. § 41-1080) may be granted 
to a current student enrolled in a K-12 culinary arts school program or similar curriculum-based programs 
requiring food employee certificates. The sponsoring school district must demonstrate to the Board of Health 
that payment of said fee will cause financial hardship. Again, all fee waiver applications reviewed this quarter 
appear to meet the criteria.  
The Board had no questions, Mr. Stratman requested approval of the applications on the Fee Waiver Application 
Summary Sheet labeled P1 through P9 and C1 through C3 
(memo and report summary attached to meeting agenda) 
President MacMillan asked if there was a motion to approve the 12 fee waiver applications presented as P1 
through P9 and C1-C3. A motion was made by Mr. Cassano to approve P1 through P9 and C1-C3 fee waiver 
applications and seconded by Ms. Baldauff. All were in favor, and the motion carried. 
5.
Air Quality Department
Greg Verkamp  
Kimberly Butler 
Mr. Verkamp and Ms. Butler presented AQ-2021-004 Rule 205 (Emission Offsets Generated by Voluntary Mobile 
Source Emission Reduction Credits) to the board, requesting that the board make a recommendation to the 
Board of Supervisors to approve the creation of Rule 205.  
Maricopa County is currently designated as a nonattainment area for both the 2008 and the 2015 ozone 
National Ambient Air Quality Standard. In ozone nonattainment areas, the Clean Air Act requires owners and 
operators proposing to construct a new major source or make a major modification to obtain emission offsets 
before the project may commence. Currently, insufficient emission reduction credits exist in the Arizona 
Emissions Bank for large businesses to use as emission offsets. The purpose of this rulemaking is to create a new 
economic development rule which will provide a mechanism for the creation of more emission reduction 
credits, specifically mobile source emission reduction credits (MERCs), for use as emission offsets. 
In January 2022, the department requested the initiation of this rulemaking, and it was approved by the board. 
A summary of the regulatory background was provided, adding that stakeholders expressed support for the 
rulemaking. In December, the department posted a Notice of Proposed Rulemaking on its EROP website for a 
30-day period. The department did not receive any comments after the Notice was posted.  The department is 
requesting that the board make a recommendation to the Board of Supervisors for approval of a new economic 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 105 of 125

4 
development rule, which is voluntary. Mr. Verkamp emphasized no one is required to comply with rule unless 
they decide to participate in the MERC program. It was confirmed that there were no comments of opposition to 
the Rule. 
President MacMillan asked if there was a recommendation to the Board of Supervisors to approve the 
creation of AQ-2021-004 Rule 205 (Emission Offsets Generated by Voluntary Mobile Source Emission 
Reduction Credits). Ms. Banahan made the recommendation, seconded by Dr. Farber. All were in favor of the 
recommendation to the Board of Supervisors for the creation of AQ 2021-004 Rule 205. 
Discussion Items 
6.
Public Health Report
Marcy Flanagan 
A. Human Resources
B. Communications
C. Infrastructure
D. Strategic Planning
E. Programs
F. Disease Update
G. Health Status/Community Health Needs Assessment (CHNA)
H. Heat Report
I. 
Future Topic
J. 
Covid Status Update
Dr. Rebecca Sunenshine 
Ms. Flanagan provided the board with Public Health’s internal departmental updates informing all that Dr. 
Sunenshine was invited to give the board a Covid status update later in the meeting. 
•
New Organizational Departmental Chart was completed end of 2022
•
Hired two additional Division Administrators
•
New Organizational changes are expected to be completed by mid-February
The primary goal surrounding the new organizational structure was to get programs and departments that have 
similar functions or focus on the same populations to be answering to the same Division Administrator. So, 
there's a lot of shuffling going around within the department and clinical services to house all their functions in 
the same division. 
•
Business practices will be consolidated and centralized by the mid-Summer or early Fall of 2023
•
Achieve more streamlined business operations and services offered to the public
Ms. Flanagan shared that she met with all the Arizona Local Health Officers, and Dr. Thresa Cullen, who currently 
is the Health Officer for Pima County, was identified as the new Health Officer for ADHS.  
Public Health’s General Fund 100 shows a positive variance (under budget) year-to-date (Epidemiology), being 
under by $590,906; most of this is due to vacancy savings and reallocations of payroll to the ARPA funding. The 
department is making great efforts to help spend monies by working closely with ASU, U of A, and the county to 
fill positions. Maricopa County’s Human Resource Department has also explored the option to telework out of 
State for those positions that are hard to fill. The county has also offered sign-on bonuses for positions like a 
nurse. All these things help with the spending of the General Fund monies being under budget, spending almost 
$600,000 in Epidemiology. An example of State-to-State wages was provided.  Ms. Flanagan believes that the 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 106 of 125

5 
county is competitive with its wages and incentives; it is known as a national situation. Public Health pay aligns 
with others. However, the problem is that the pay the department has and the experience required for that pay 
match an entry-level in those fields. The county is willing to examine this closely. The incentives are being 
provided. It was also noted that people in the workforce like to move around nowadays as opposed to 
historically staying in one position.  
Dr. Sunenshine presented the board with an update on infectious diseases giving an overview of each slide. 
Global & National COVID-19 update 
•
It’s believed that what’s happening in China will have some global impact.
•
Reports show that XBB.1.5 has been spreading rapidly
•
Increased media coverage surrounding the newest variant XBB.1.5
•
Public Health expects the Coronavirus to constantly mutate, which is what that type of virus does
•
XBB.1.5 is rapidly spreading, as shown in Denmark and the UK
•
People have immunity to the last variant, XBB.1.5 is very infectious than the last variant; outcompete
the last strain
•
Almost 43% for National Region 9 classified as how Public Health quality themselves in the preparedness
world; were lumped with a bunch of states
•
XBB.1.5 constitutes about 16% of all isolated viruses
Global & National COVID-19 Update
Global
•
Per WHO, reported cases have decreased slightly since
the prior week; deaths remained fairly constant .
•
China reported on January 12 that nearly 60,000 people
with COVID-19 have died since early December, not 
including people who died at home. 
•
XBB.1.5 identified in Denmark and the UK.
National
•
XBB.1.5 increased from 30.4% to 43.0% of
sequenced samples.
Region 9 (AZ, CA, NV, HA, Pacific Islands)
•
XBB.1.5 associated with 15.8% of sequenced samples.
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 107 of 125

6 
COVID-19 in Maricopa County 
•
The epidemiology curve for Maricopa County shows the last 60 days have been on a downward trend
with COVID-19 for case numbers
•
Many people are not being tested in a lab vs. in their homes, so the numbers are unrepresented here
0
200
400
600
800
1,000
1,200
1,400
1,600
1,800
11/20/22
11/25/22
11/30/22
12/5/22
12/10/22
12/15/22
12/20/22
12/25/22
12/30/22
1/4/23
1/9/23
1/14/23
COVID-19 in Maricopa County
Over the last 60 days, the number of COVID-19 cases 
reported to MCDPH has been decreasing.
60 - day epi curve
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 108 of 125

7 
COVID-19 Hospital Metrics
The metric shown are in addition to case counts; the top graph is the number of new admissions due to COVID-
19 
COVID-19 Variants 
A comparison was provided, displaying XBB.1.5 being at 3% (top right bar) with that of Region 9 being 16% and 
43% nationally. The county has a much smaller proportion of XBB.1.5 compared to the rest of the country. The 
COVID-19 Hospital Metrics
36.5% decrease in new COVID-19 
admissions from last week.
0.7% decrease in % of ICU beds in use 
by COVID -19 patients from last week
0.9% decrease in % of inpatient beds in 
use by COVID -19 patients from last 
week.
Mon, Nov 14, 2022 – Sat, Jan 14, 2023
New Admissions, Confirmed COVID-19 per 100,000 population, Last 7 Days
Daily % Beds Used
Daily % ICU Beds Used
COVID-19 Variants
59%
53%
39%
39%
32%
23%
16%
BA.5, 26%
16%
18%
29%
34%
34%
35%
39%
BQ.1.1, 43%
8%
11%
13%
15%
18%
26%
26%
BQ.1, 17%
6%
5%
10%
3%
6%
3%
5%
BF.7, 4%
3%
4%
2%
5%
3%
7%
7%
BN.1, 3%
5%
3%
BA.4.6, 3%
2%
2%
2%
4%
2%
3%
XBB, 3%
XBB.1.5, 3%
10/30/22
11/6/22
11/13/22
11/20/22
11/27/22
12/4/22
12/11/22
12/18/22
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 109 of 125

8 
Reports show that almost every variant trend hits the East coast first and then travels West.  Public Health has 
plans in place to address lots of outbreaks and situations; the difficulty is when something brand new like 
COVID, it takes time to gather how the virus behaves, spreads, and what mitigation efforts will work. Which 
helps in the future, but it didn’t help when this occurred. No one had ever seen something such as this that 
lasted this long in over 100 years. There is talk about annual vaccines; however, according to WHO and the CDC, 
we are still in a pandemic that has lasted over three years, and plans are forming as they move forward. 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 110 of 125

9 
Influenza 
Influenza
There were 301 influenza cases reported in week 2 (beginning Jan 8) with a 
2022-2023 season total of 16,636cases.
0
200
400
600
800
1,000
1,200
1,400
1,600
1,800
2,000
2,200
2,400
2,600
2,800
3,000
3,200
3,400
Week 40
Week 41
Week 42
Week 43
Week 44
Week 45
Week 46
Week 47
Week 48
Week 49
Week 50
Week 51
Week 52
Week 1
Week 2
Week 3
Week 4
Week 5
Week 6
Week 7
Week 8
Week 9
Week 10
Week 11
Week 12
Week 13
Week 14
Week 15
Week 16
Week 17
Week 18
Week 19
Week 20
Week 21
Week 22
Week 23
Week 24
Week 25
Week 26
Week 27
Week 28
Week 29
Week 30
Week 31
Week 32
Week 33
Week 34
Week 35
Week 36
Week 37
Week 38
Week 39
Current flu season (2022-2023) N=16,647*
5 season wkly average (2017-2022) N=11,771
2021-2022 Season N=10,024
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
0%
2%
4%
6%
8%
10%
12%
14%
Week 40
Week 41
Week 42
Week 43
Week 44
Week 45
Week 46
Week 47
Week 48
Week 49
Week 50
Week 51
Week 52
Week 1
Week 2
Week 3
Week 4
Week 5
Week 6
Week 7
Week 8
Week 9
Week 10
Week 11
Week 12
Week 13
Week 14
Week 15
Week 16
Week 17
Week 18
Week 19
Week 20
Week 21
Week 22
Week 23
Week 24
Week 25
Week 26
Week 27
Week 28
Week 29
Week 30
Week 31
Week 32
Week 33
Week 34
Week 35
Week 36
Week 37
Week 38
Week 39
Percent of Hospital Visits
Current Season (2022-2023)
5 season wkly average (2017-2022)
Baseline
Last Season (2021-2022)
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
3.9% of all ED and UC visits in week 2 (beginning Jan 8) 
presented with Influenza-like Illness (ILI).
Influenza-like illness in MC hospitals and 
urgent cares
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 111 of 125

10 
RSV 
An overview of Flu data was shared, showing a dramatic decline. Based on a five-year average, flu season 
traditionally peaks around the end of December, which is what the charts show. A discussion was had 
concerning the different times' flu peaks in our county. Public Health is aware that there are still people who 
need to be vaccinated, and they’re still people at very high risk. Public Health will continue to offer vaccinations 
RSV
There were 214 RSV cases reported in week 2 (beginning Jan 8) with a 2022-2023 
season total of 7,558 RSV cases.
0
100
200
300
400
500
600
700
800
900
1,000
Week 40
Week 41
Week 42
Week 43
Week 44
Week 45
Week 46
Week 47
Week 48
Week 49
Week 50
Week 51
Week 52
Week 1
Week 2
Week 3
Week 4
Week 5
Week 6
Week 7
Week 8
Week 9
Week 10
Week 11
Week 12
Week 13
Week 14
Week 15
Week 16
Week 17
Week 18
Week 19
Week 20
Week 21
Week 22
Week 23
Week 24
Week 25
Week 26
Week 27
Week 28
Week 29
Week 30
Week 31
Week 32
Week 33
Week 34
Week 35
Week 36
Week 37
Week 38
Week 39
Current RSV season (2022-2023) N=7,562
5 Season Weekly Average (2017-2022) N=3,482
Last season (2021-2022) N=3,066
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
COVID-19, influenza, and RSV
Reported cases of COVID-19, flu, and RSV are decreasing.
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
10,000
40
42
44
46
48
50
52
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
Reported Cases
MMWR Week
COVID
RSV
FLU
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 112 of 125

11 
and push them out. Fully vaccinated people are nineteen times less likely to die. Being fully vaccinated and 
getting boosters significantly helps. Public Health receives its guidance from the FDA and CDC. 
Mpox (formally known as Monkeypox) 
The chart provided an overview of how Mpox peaked in August vs. now there are no cases since January, which 
is similar to the county’s Hepatitis curve, in which the county was able to provide more vaccinations ad knock 
out the disease, unlike COVID, it has more to do with the way it’s transmitted, and with the portion of the 
population at risk because that was vaccinated.  
Mpox
There have been 483 mpox cases in Maricopa County, 0 reported since 2023.
0
2,000
4,000
6,000
8,000
10,000
12,000
14,000
16,000
18,000
0
3
6
9
12
15
5/1/22
6/1/22
7/1/22
8/1/22
9/1/22
10/1/22
11/1/22
12/1/22
1/1/23
# of Vaccinations
Reported Cases
Data are provisional;
Cases may increase
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 113 of 125

12 
Dr. Sunenshine closed out her presentation with the Pfizer Bivalent, which has received a lot of media coverage 
lately. There are no recommendations to change vaccination recommendations at this time, but the department 
will keep following them. 
Announcements and Current Events 
President/ 
Board Members 
There was nothing presented. 
Adjournment 
President MacMillan 
There being no further business, Dr. Stander made a motion to adjourn the meeting, and Ms. Baldauff seconded 
the motion. The motion passed unanimously. The meeting was adjourned at 4:17 p.m. 
Preliminary safety signal among Pfizer 
Bivalent COVID-19 recipients aged 65+ 
years
•
Preliminary signal in CDC's VSD (Vaccine Safety Datalink) "raised aquestion of whether people 65 
and older who have received the Pfizer-BioNTech COVID-19 Vaccine, Bivalent were more likely
to have an ischemic stroke in the 21 days following vaccinationcompared with days 22-42 
following vaccination."
•
No similar signal seen for Moderna Bivalent COVID
-19 Vaccine
•
No similar signals in other data
sets (VAERS, CMS, VA, Pfizer global safety database )
•
No similar signals from other countries
•
CDC and FDA are running additional analyses and will present the findings at an FDA VRBPAC
meeting on January 26.
•
No changes to vaccine recommendations at this time.
hƩps://www.cdc.gov/coronavirus/2019-ncov/vaccines/safety/bivalent-boosters.html
FDA/CDC Press Release (1/13/2023)
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 114 of 125

From: Nicole Harden (PHS) 
Sent: Tuesday, September 3, 2024 10:13 AM
Cc: Vera Sampler (PHS) <Vera.Sampler@maricopa.gov>; Karalyn Spicer (PHS)
<Karalyn.Spicer@maricopa.gov>
Subject: FW: Board of Health Notification for MCAQD Rules 204 and 205
Good morning, Members of the Board!
Please review the email below on behalf of the Maricopa County Air Quality
Department.
Thank you!
Nicole Harden (She/Her)
OSCO Division Office Assistant
Public Health
Organizational Support & Community Operations
4041 North Central Avenue, Suite 1400 Phoenix, AZ 85012
O: 480.271.8374
[ Maricopa.Gov ]
Facebook | Instagram | X | YouTube | LinkedIn
Dear Members of the Board of Health,
This email is to notify you that on August 22, 2024, the U.S. Environmental
Protection Agency (EPA) proposed conditional approval of Maricopa County Air
Pollution Control Regulations, Rule 205 (Emission Offsets Generated By
Voluntary Mobile Source Emission Reduction Credits). The proposed conditional
approval identified deficiencies in Rule 205 that must be addressed prior to
being permanently approved into the Arizona State Implementation Plan. Per the
Maricopa County Air Quality Department (MCAQD) Enhanced Regulatory
Outreach Program flow charts, MCAQD is notifying the Board that MCAQD is
revising the rule to address EPA deficiencies. MCAQD plans to hold a
stakeholder workshop on September 17, 2024, to discuss the deficiencies and
remedies with stakeholders.
In addition, this email is to notify you that MCAQD plans to begin the rulemaking
process to revise Rule 204 (Emission Reduction Credit (ERC) Generation,
Certification, And Use). The EPA has not formally acted on Rule 204 but has
informed MCAQD that Rule 204 has many of the same deficiencies as Rule 205
and is not approvable in its current form. MCAQD plans to revise Rule 204
through a stakeholder process to address the rule approvability issues.
Greg Verkamp
Planning Supervisor
Air Quality
301 W. Jefferson St., Suite 410 Phoenix, AZ 85003
C: 602-206-0564
E: Gregory.Verkamp@Maricopa.Gov
[ Maricopa.Gov ]
Facebook | Instagram | Twitter | YouTube | LinkedIn
Customer Satisfaction Survey
Board of Health Notification for MCAQD Rules 204 and 205
Return to list of attachments
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 115 of 125

This Message Is From an External Sender
This message came from outside your organization. Please use caution when corresponding outside the
county.
From:
Mccurry, Craig
To:
Will Adrian (AQD)
Cc:
Gregory Verkamp (AQD); Kimberly Butler (AQD)
Subject:
Input from our CA MERC consultant on Rule 205
Date:
Wednesday, July 17, 2024 10:49:25 AM
Attachments:
image001.png
Will, just passing along an assessment I asked for from our MERC consultant in CA:
Given that part of the calculation description, it is going to be difficult to generate credits and in my
opinion Rule 205 is internally inconsistent. 
First, the definition of baseline emissions at 203 is:
BASELINE EMISSIONS: The average rate at which a baseline vehicle would have actually emitted the
pollutant in absence of generating emission reductions during the two preceding calendars years, or two
calendar years more representative of normal emissions within the 5-year period immediately before the
reduction in qualifying emissions.
Which can be compared to the text that you highlighted from Appendix A. 
Baseline vehicle engine model year corresponds to the calendar year in which the emission reductions are
generated by replacing or retrofitting the baseline vehicle.
Changing the model year of the baseline vehicle from what it actually is (which is what defines what the
vehicle would have “actually emitted”), to the current calendar year is not what we did for WM originally
and would have precluded the generation of any significant MERCS.
Another internal inconsistency can be found in the definition of replacement vehicle at 207:
207:  REPLACEMENT VEHICLE: Vehicle used to generate certified credits that is certified to an emission
limit less than the baseline vehicle it replaces and is in compliance with the most recent applicable federal
emission standard at the time of replacement.
If you have to use the same model year for the baseline and replacement vehicle, it’s generally going to
be impossible to generate credits.
What I think Appendix A should have said is:  Baseline vehicle engine emissions are to be estimated
based on the vehicle’s actual model year in the corresponds to the calendar year in which the emission
reductions are generated by replacing or retrofitting the baseline vehicle.
This is what was done for WM’s NG vehicles for both the baseline and the new vehicles. 
Maybe we can discuss in more detail sometime next week,
Craig
Craig McCurry, P.E.
Senior Environmental Engineer
Copies of all written and electronic Stakeholder input
Return to list of attachments
Return to Stakeholder #1: Reponses #1 through #2 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 116 of 125

Ocotillo EHS
W: 480 255 9481
C:  602 617 9110
craig.mccurry@intel.com
“Great moments are born from great opportunity, that's what you've earned tonight.
If we played them ten times they might win nine. But not this game, not tonight”
Herb Brooks, 1980 US Olympic Hockey Coach
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 117 of 125

This Message Is From an External Sender
This message came from outside your organization. Please use caution when corresponding outside the
county.
From:
Mccurry, Craig
To:
Will Adrian (AQD)
Cc:
Kimberly Butler (AQD); Gregory Verkamp (AQD)
Subject:
RE: MCAQD Draft Rule 205
Date:
Friday, September 27, 2024 2:38:11 PM
Attachments:
image001.png
image002.png
The other item I forgot about is it clear that the buyer of the credits only needs to produce
extra credits if it is using 100% of its NOx limit.
Thanks, Craig
Craig McCurry, P.E.
Senior Environmental Engineer
Ocotillo EHS
W: 480 255 9481
C:  602 617 9110
craig.mccurry@intel.com
“Great moments are born from great opportunity, that's what you've earned tonight.
If we played them ten times they might win nine. But not this game, not tonight”
Herb Brooks, 1980 US Olympic Hockey Coach
From: Mccurry, Craig 
Sent: Friday, September 27, 2024 1:17 PM
To: 'Will Adrian (AQD)' <William.Adrian@maricopa.gov>
Cc: Kimberly Butler (AQD) <Kimberly.Butler@Maricopa.gov>; Gregory Verkamp (AQD)
<Gregory.Verkamp@Maricopa.gov>
Subject: RE: MCAQD Draft Rule 205
Will, got your message.  Only minor comments I spoke about briefly but understand why
they exist – and were included in the EPA comments Intel submitted last week are:
1. Intel is disappointed that there is not a Clean Diesel option to create MERCs
in Rule 205.  A new Clean Diesel engine can match the NOx reductions that
CNG-powered engine can achieve (per MOVES).
2. Intel has a hard time understanding the intent of having a VMT requirement.
If the Fleet owner of the associated MERCs does not change out vehicles with
equal or cleaning burning engines they could end up taking joy rides around
Phoenix just to meet their VMT requirement and this will actually result in
higher emissions. Using that same logic the MERC buyer should get a higher
amount of MERCs in years where the Fleet goes over its VMT requirement.
3. Would of preferred off-road vehicles be in 205 (Lisa Beckham also feels that
Return to Stakeholder #1: Reponses #3 through #6 
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 118 of 125

way) but I get the timing element of why it isn’t.
You should also reach out to United Dairymen of Arizona:
Gabriel Hernandez Gabriel.Hernandez@udaz.org; Brandon Clark bclark@udaz.org
Thanks, Craig
Craig McCurry, P.E.
Senior Environmental Engineer
Ocotillo EHS
W: 480 255 9481
C:  602 617 9110
craig.mccurry@intel.com
“Great moments are born from great opportunity, that's what you've earned tonight.
If we played them ten times they might win nine. But not this game, not tonight”
Herb Brooks, 1980 US Olympic Hockey Coach
From: Will Adrian (AQD) <William.Adrian@maricopa.gov> 
Sent: Friday, September 27, 2024 10:00 AM
To: Mccurry, Craig <craig.mccurry@intel.com>
Cc: Kimberly Butler (AQD) <Kimberly.Butler@Maricopa.gov>; Gregory Verkamp (AQD)
<Gregory.Verkamp@Maricopa.gov>
Subject: MCAQD Draft Rule 205
Good morning Craig,
This message is just to follow-up on our MCAQD ERC workshop comment period and to
confirm you have no additional comments on the current draft Rule 205 (Emission Offsets
Generated by Voluntary Mobile Source Emission Reduction Credits) for the local Maricopa
County rulemaking. 
In order for comments to be incorporated into our Notice of Proposed Rulemaking draft rule
version, the comment period stated in the workshop for draft Rule 205 was 9/25.
We look to post the NPR next week on our EROP website, please feel free to reach out
with any questions or issues.
Thank you,
Will Adrian
Senior Planner
Air Quality
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 119 of 125

301 W. Jefferson St., Suite 410 Phoenix, Arizona 85003
C: 602-206-1941
E: William.Adrian@Maricopa.Gov
[ Maricopa.Gov ]
Facebook | Instagram | X | YouTube | LinkedIn
Customer Satisfaction Survey
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 120 of 125

This Message Is From an External Sender
This message came from outside your organization. Please use caution when corresponding outside the
county.
Attachments:
 Rule 205 WM Draft Comments 9 26 24.docx
From: Bearden, David <dbearde2@wm.com>
Sent: Friday, September 27, 2024 10:57 AM
To: Will Adrian (AQD) <William.Adrian@maricopa.gov>
Subject: County Rule 205 latest version
Hello Will,
Here’s the comment sheet we discussed yesterday.
Although the process is near final take a look maybe there will be some useful info for you.
Dave Bearden
Senior Environmental Protection Manager
Waste Management
222 S. Mill Ave., Suite 333
Tempe, AZ  85281
602-708-9815
Recycling is a good thing. Please recycle any printed emails.
Return to Stakeholder #2: Reponses #7 through #22 
1
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 121 of 125

September 26, 2024 
To:  Rule Making, Maricopa Air Quality 
From: Dave Bearden, WMAZ 
Subject: Waste Management of Arizona (WMAZ) Comments on Proposed Rule 205 
WMAZ has reviewed the Maricopa County draŌ Rule 205 posted September 9, 2024.  
WMAZ recognized mobile sources as dominant contributors to the deterioraƟon of air 
quality in Maricopa County and partnered with Intel to develop a mechanism to reduce 
mobile emissions by incenƟvizing the use of cleaner vehicles.  AddiƟonally, we appreciate 
the hard work that the County and EPA are puƫng into the development of this rule.   
In 2021 WMAZ entered the MERC program with the understanding of the tracking and 
reporƟng obligaƟons would extend for twenty years and the anƟcipated level of effort to 
meet those obligaƟons.  In order to comply with the evolving requirements, WMAZ has 
incurred addiƟonal cost to develop programming, using exisƟng data, to determine the 
mileage within the non-atainment area.  This cost did not include the GIS tracking 
hardware, data storage capacity or maintenance as we already had this infrastructure in 
place. 
WMAZ acknowledges that while the addiƟonal requirements added aŌer the cerƟficates 
were issued were burdensome, they were not prohibiƟve.  However, several of the 
proposed Rule 205 changes add complexity and burdens that risk the rule being prohibiƟve. 
Our comments below are based on our experience with the exisƟng program and WMAZ’s 
earnest commitment to improving the environment in which we work and live.   
General Comments 
a. The proposed Appendix A, calculaƟons for determining the credits, uses the
actual model year for the baseline vehicles emissions which will likely increase
the credits compared to the approach used in our 2021 project. This is
favorable.
b. The compliance of point for our current MERC program is based upon vehicle
replacement and not on the mileage.  The Proposed Rule will change that as it
requires as 12-mn VMT rolling calculaƟon and if there is an emissions short fall
then the credit generator and user must take prompt acƟon to report, plan to
resolve the short fall and if delays occur in resolving the shorƞall the user may
face permit modificaƟons and/or compliance issues. Currently, the agreed
upon methodology requires an annual evaluaƟon of the mileage and
calculaƟon of the emission reducƟon.  Increasing to monthly is Ɵme
consuming and adding the compliance steps will be complex.
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 122 of 125

c.
The 200 mile removal requirement from the Non-Atainment Area excludes
ciƟes like Tucson and Flagstaff which will  likely be is too restricƟve.  At Ɵmes
WMAZ moves trucks from Phoenix to these areas.   Other fleets may wish to
do the same. This may limit parƟcipaƟon in this voluntary rule.
Specific Comments 
d. 218 - add in “….any other adjustments (e.g. for load factors)…” aŌer “…MOVES
output emissions factors.”
e. 219 – add a definiƟon for “RaƟo Adjusted Emission Factor” found in
401.3,a(2).
f.
222 – add a clarificaƟon that the federal engine manufacturer emission
standards are not applicable requirements for fleet operators.
g. 301.2(c) – Please add text to clarify that our current process of amending
vehicle lists as a administraƟve revision is not  a modificaƟon requiring public
parƟcipaƟon and the revision steps in SecƟon 407 of Rule 220.
h. 301.2(d)1(c) & 302.2(f) - Note that future compleƟon dates for the
replacement of vehicles are difficult to predict thus there needs to be some
flexibility and leniency.  When a permit is used for MERC enforcement, and if
the compleƟon date is in the permit is not met, it would be a permit violaƟon.
OŌen Ɵmes these delays are outside of control of permitee.  We recommend
that a permit noƟficaƟon be allowed to modify this date, obviously
coordinated with the MERC user to ensure that their start up needs are met.
i.
302.2(b)(3) & (4) – need to be removed.  If the current version of GPS system
and soŌware is tracking vehicles then there is no reason to spend funds on a
new system.  System changes will have unintended impacts across related GIS
fleet systems, such as requiring equipment change outs conflicts with many
other operaƟon systems on the trucks.  AddiƟonally, we operate with the
same GPS system naƟonally.  The potenƟal impact of this makes this an
unreasonable request. AddiƟonally, this is also more stringent that our current
permit.
j.
302.2(b)(c) – Using 200 miles means in all 4 direcƟons of the edge of
Nonatainment Area trucks could not be relocated in a metropolitan area in
Arizona.  The closest potenƟal metropolitan areas would be in El Centro, CA,
Las Vegas, NV, Farmington or Albuquerque, NM or in the county of Mexico.
Basically, this prohibits areas like Tucson & Flagstaff which are in atainment.
This may hurt the viability of the rule as it would rule out firms that may want
to parƟcipate but cannot be due to distance logisƟcs or financial impact.
WMAZ proposes language that gives the generator the opƟon of performing a
demonstraƟon or air modeling to show that original fleet vehicle operaƟng
closer will have no impact to the Maricopa non-atainment area.  This is also
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 123 of 125

more stringent that our current permit, and we have already moved units to 
Tucson as an example.  
k. 302.2(d) -  The statement “The permited generator shall further ensure that
any replaced baseline vehicle that is subsequently replaced again, is not
operated in any other capƟve fleet owned or operated by the permited
generator in the applicable Maricopa County nonatainment area”  should be
removed as this is confusing, and any subsequent replacement would meet
the low emissions rate approved in the MERC.
l.
401.2 - 12-month rolling VMT -  a. Our current MERC program with Maricopa
County is based upon vehicle/engine replacement and not on the mileage,
and currently, the agreed upon methodology requires an annual evaluaƟon of
the mileage.  Increasing that to monthly is Ɵme consuming and complex.
Certainty if the mileage matches the applicaƟon that is preferable, but it
should not be point of compliance.  This is a reasonable approach that will
make the program viable.  b. WM has spare trucks to replace out of service
trucks and has a stable business within the non-atainment area; however,
many companies may not have extras units readily available thus this
requirement will likely be limiƟng the viability of ERC program. c.  Moreover, if
there are lower miles, the objecƟve of lowering emissions is met, as CNG is
1/10th emissions of diesel, and parƟcipants in this voluntary program should
not face compliance issues.  d) Currently we are assessing the VMT and the
emissions reducƟons on an annual basis which provides Ɵme for the fleets to
assessment, make repairs or order replacements. e) AddiƟonally, the VMT
isn’t proporƟonal to the overall emissions, as each vehicle will have a different
emission factor, and then subsequent replacements will likely differ again.
Therefore, a reducƟon in VMT doesn’t easily equate to a negaƟve shorƞall.
m. 401.3 Credit User VMT – Note that the credit user will may have difficulty
complying:   1) As an example, if WM provides Intel VMT short fall how would
you calculate the emissions reducƟon from the short fall with just the VMT? 2)
in (3) 10 days to develop a plan and the 3 months to resolve is not adequate
Ɵme; if part of the soluƟon is adding an extra vehicle that could take 9 months
for the fleet owner. 3) requirement (4) requires a permit mod within 90 days
to reduce emissions.  This seems un-reasonable for a large and complex
facility. Then in (5) missing these steps would be violaƟon.
n. 504.3 – revise “current vehicle mileage” to “monthly vehicle mileage”.
o. 505.3 – “the 10th of the month”, should be “10th day of the VMT calculaƟon”.
p. App. A, A,3 – 1) using the latest version of MOVES could create a difference
from the MOVES used for a approved MERC applicaƟon.  Thus, we
recommending using version of the MOVES from the MERC applicaƟon.
Maricopa County • Air Quality Department • Rule 205 Report to the Board of Supervisors
Page 124 of 125

Maricopa County 
Air Quality Department 
Planning and Analysis Division 
Maricopa.gov/AQ