AQ-2013-005_PREAMBLE 2015-12-03.PDF

DRAFT NOTICE OF FINAL RULEMAKING
MARICOPA COUNTY AIR POLLUTION CONTROL REGULATIONS
PREAMBLE
AQ-2013-005-NEW SOURCE REVIEW (NSR)
1. Rules affected Rulemaking action
Rule 100: General Provisions and Definitions Amend
Rule 200: Permit Requirements Amend
Rule 210: Title V Permit Provisions Amend
Rule 220: Non-Title V Permit Provisions Amend
Rule 230: General Permits Amend
Rule 240: Permit Requirements For New Major Sources and Major Modifications to
Existing Sources Amend
Rule 241: Permits for New Sources and Modifications to Existing Sources Amend
Rule 500: Attainment Area Classification Repeal
Rule 510: Air Quality Standards Amend
Rule 600: Emergency Episodes Amend
Appendix D: List of Insignificant Activities Repeal
Appendix E: List of Trivial Activities Repeal
2. Statutory authority for the rulemaking:
Authorizing statutes: C.F.R. 4825-1, January 2, 1994 (F.R Doc. 94-802 Filed 01-11-94)
A.R.S. §§ 49-474, 49-479, and 49-480
Implementing statute: A.R.S. § 49-112
3. The effective date of the rule:
Tentative date of adoption: February 3, 2016
4. List of all previous notices appearing in the Register addressing this rulemaking:
Notice of Proposed Rulemaking: 21 A.A.R. 1302, July 31, 2015
Notice of Supplemental Proposed Rulemaking: 21 A.A.R. 2124, October 2, 2015
Notice of Supplemental Proposed Rulemaking: 21 A.A.R., [Page Number], December 18, 2015
5. The department’s contact person who can answer questions about the rulemaking:
Name: Kathleen Sommer
Maricopa County Air Quality Department
Planning and Analysis Division
Address: 1001 N Central Avenue, Suite 125
Phoenix, Arizona 85004
Telephone: (602) 506-6010
Fax: (602) 506-6179
E-Mail: aqplanning@mail.maricopa.gov
6. Explanation of the rule, including the department’s reasons for initiating the rulemaking:
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Summary:
The purpose of this rulemaking is to update the Maricopa County Air Quality Department’s (department’s) New Source
Review (NSR) rules in order to secure their approval as part of the state implementation plan (SIP) under the federal Clean
Air Act. The update will be consistent with revisions the Arizona Department of Environmental Quality (ADEQ) and the
U.S. Environmental Protection Agency (EPA) made to the NSR Program required by the federal Clean Air Act (CAA).
The proposed amendments included in the rulemaking consist of extensive revisions to the county’s major NSR program as
well as new NSR requirements for minor sources and minor modifications designed to protect the national ambient air quality
standards (NAAQS). (Whether a source or modification is major or minor depends on the level of emissions, as described in
greater detail below.)
There is currently a significant discrepancy, known as the “SIP gap,” between the NSR rules as set forth in the Maricopa
County Air Pollution Control Regulations and the rules that have been approved by the EPA into the Maricopa County
portion of the Arizona SIP. Once approved, the amended rules will eliminate the SIP gap.
This rulemaking also includes proposed conforming and technical changes to rules related to NSR, such as requirements for
the general permit program.
Background:
Clean Air Act NSR Requirements
Section 110(a)(2)(C) of the federal Clean Air Act (the “Act” or “CAA”), 42 U.S.C. 7410(a)(2)(C), requires SIPs to:
include a program to provide for the … regulation of the modification and construction of any stationary source
within the areas covered by the plan as necessary to assure that national ambient air quality standards are achieved,
including a permit program as required in parts C and D of this subchapter… .
Because regulations adopted under this section apply to newly constructed and modified, as opposed to existing, sources they
are commonly referred to as “new source review” programs.
Part C of title I of the Act, 42 U.S.C. 7470-7492, establishes the NSR requirements for major sources that are constructed or
modified in areas that have attained the NAAQS for one or more criteria pollutants (ozone, carbon monoxide, nitrogen
dioxide, sulfur dioxide, PM10, PM2.5 and lead). Sources that belong to the list of categories set forth in section 169(1) of the
Act, 42 U.S.C. 7479(1), are major if they emit or have the potential to emit 100 or more tons per year of a regulated air
pollutant. Other sources are subject to a 250 tons per year threshold.
The program required by Part C is known as “Prevention of Significant Deterioration” (PSD) because its purpose is to
prevent air quality in attainment areas from deteriorating to the level of the NAAQS. See CAA § 160. PSD, therefore,
establishes or requires EPA to establish maximum allowable increases, known as “increments,” over existing concentrations
of criteria pollutants and requires permit applicants subject to PSD to demonstrate that a new source or modification’s
emissions will not result in a violation of the increments or the NAAQS. PSD also requires the installation of the Best
Available Control Technology (BACT), defined as “the maximum degree of reduction of each pollutant subject to regulation
under this chapter emitted from or which results from any major emitting facility, which the permitting authority, on a case-
by-case basis, taking into account energy, environmental, and economic impacts and other costs, determines is achievable for
such facility.” 42 U.S.C. 7479(3).
Part D of Title I establishes NSR requirements for major sources and modifications in nonattainment areas. Under Subpart 1
of Part D, 42 U.S.C. 7501-7509a, a major source is defined as any source that emits or has the potential to emit 100 tons per
year or more of a pollutant for which an area has been designated nonattainment. Subpart 2, 3, and 4 of Part D, 42 U.S.C.
7511-7511f, establishes lower major source thresholds for certain ozone, carbon monoxide and PM10 nonattainment areas.
Permit applicants subject to Part D must demonstrate that a major source or modification will comply with the lowest
achievable emission rate (LAER) and that reductions in emissions from the same source or other sources will offset any
emissions increases from the source or modification.
In addition to requiring compliance with the specific major NSR requirements of Parts C and D, section 110(a)(2)(C),
7410(a)(2)(C), requires “regulation of the modification and construction of any stationary source within the areas covered by
the plan as necessary to assure that national ambient air quality standards are achieved.” EPA refers to 110(a)(2)(C) programs
that apply to non-major sources and to minor modifications to major sources as “minor NSR.” 76 Fed. Reg. 38748, 38752
(July 1, 2011).
EPA NSR Regulations
EPA has promulgated regulations establishing the elements a state program must contain to satisfy section 110(a)(2)(C) at 40
CFR 51, Subpart I (§§ 51.160-51.166) and federal implementation plans at 40 CFR 52 § 52.21 and 40 CFR 51, Appendix S.
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Sections 51.165 and 51.166 establish the requirements for nonattainment NSR and PSD programs, respectively. These rules
are highly detailed and restrictive. States seeking approval of major NSR programs must either strictly conform to these rules
or demonstrate that any deviations are at least as stringent as EPA’s program.
Both § 51.165 and 51.166 limit the applicability of major NSR to the construction of a new major source or a “major
modification” to a major source. A major modification is defined as a physical or operational change that will result in both a
significant increase and a significant net increase in the emissions of a regulated NSR pollutant at an existing major source.
For criteria pollutants and their precursors, “significant” is defined as:
Carbon monoxide 100 tons per year (tpy)
Nitrogen oxides 40 tpy
Sulfur dioxide 40 tpy
Volatile organic compounds 40 tpy
Lead 0.6 tpy
PM10 15 tpy
PM2.5 10 tpy
As EPA has noted, the “Federal regulations for minor source programs [at 40 CFR 51.160-164] are considerably less detailed
than the requirements for major sources.” 71 Fed. Reg. 48696, 48700 (Aug. 21, 2006). Under the minor NSR regulations, a
state program must contain “legally enforceable procedures” to prevent the construction or modification of a minor source if
it will “result in a violation of applicable portions of the control strategy” for compliance with the NAAQS or “interfere with
the attainment or maintenance of a” NAAQS. 40 CFR 51.160.
A minor NSR program need not apply to all new and modified sources, but it must “identify types and sizes of facilities,
buildings, structures, or installations which will be subject to” minor NSR and “discuss the basis for determining which
facilities will be subject to review.” 40 CFR 51.161(e). As EPA has noted:
Applicability thresholds are proper in [a minor NSR program] provided that the sources and modifications with
emissions below the thresholds are inconsequential to attainment and maintenance of the NAAQS. 71 Fed. Reg.
48701.
The appropriate threshold levels for NSR applicability are often referred to as “de minimis” levels. The program must allow a
minimum 30-day period to comment on the applicant’s minor NSR application and the agency’s proposed decision. 40 CFR
51.161.
Maricopa County’s NSR SIP and Current NSR Rules
Before the department’s creation in 2004, Maricopa County’s Bureau of Air Pollution Control was responsible for
administering Maricopa County’s air quality program and the Board of Supervisors adopted its original major and minor
NSR rules. Maricopa County implemented NSR through an installation permit program, which required owners or operators
to obtain an installation permit before beginning construction of a new source or a modification to an existing source. See
former Maricopa County Bureau of Air Pollution Control Regulation Rule 21, which, along with other rules cited in this
discussion, can be found at EPA Region 9’s web site at: http://www2.epa.gov/aboutepa/epa-region-9-pacific-southwest. A
separate operating permit was required before the owner or operator was allowed to begin operation of the source or
modification. See former Rule 220 Permits to Operate.
In 1988, EPA approved the Maricopa County nonattainment NSR provisions into the SIP. 53 Fed. Reg. 30220 (Aug. 10,
1988). Effective November 22,1993, EPA delegated PSD authority to Maricopa County via a PSD Delegation Agreement. 59
FR 1730 (January 12, 1994).
The SIP Gap
EPA last approved revisions to the Maricopa County NSR SIP in 1988. See 53 Fed. Reg. 30220 (Aug. 10, 1988). Since the
amendments last approved by EPA were adopted, the county has re-organized forming the Maricopa County Air Quality
Department and has made substantial revisions to the program.
Most significantly, in 1992 through 1993, the Arizona State adopted legislation, followed by conforming rule amendments, to
move from the old installation and operating permit program to a “unitary” program that authorizes both construction and
operation in a single permit. NSR requirements for new sources are now enforced as part of the issuance of a single permit
that also ensures compliance with all other applicable requirements of state and federal air quality laws. For major sources,
these permits are designed to comply with title V of the Act, as well as Parts C and D of title I. Major modifications subject
to major NSR now require a significant revision to the permit for an existing source, rather than a new installation permit.
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Other modifications that formerly required an installation permit may now proceed under either a significant or minor permit
revision.
In addition to adopting the unitary permit program, Maricopa County also has updated its NSR rules to incorporate:
- the PM10 and PM2.5 NAAQS,
- the PM10 increments,
- the nitrogen dioxide increments,
- the 1997 eight-hour ozone NAAQS,
- the “WEPCO” rule redefining the method for determining whether a modification to an electric generating unit is major,
and
- various technical amendments.
None of these changes are included in the approved NSR SIP for Maricopa County.
Under federal law, Maricopa County remains obligated to continue enforcing the old NSR program until EPA approves the
new one. Fortunately, the new program is in most cases more stringent than the old, so that compliance with current rules is
largely sufficient to assure compliance with the approved NSR SIP. There are a few instances, however, in which the old
rules require review procedures that go beyond the current program. Maricopa County has had to issue guidance explaining
that in these cases the department will apply the approved SIP, rather than the current rules.
It would obviously be preferable for the requirements of the SIP and the current rules to match. Maricopa County is,
therefore, seeking through these proposed rule amendments to eliminate the SIP gap for the permit program.
EPA Amendments to Major NSR
Maricopa County has attempted to secure EPA approval of prior versions of its NSR rules, but so far without success. Since
Maricopa County last updated its NSR rules, EPA has adopted substantial revisions to the major NSR program, making
additional amendments necessary before approval by EPA can be secured.
Most significantly, on December 31, 2002, EPA promulgated comprehensive amendments, known as “NSR reform,” to the
regulatory methods for determining whether a major modification has occurred. 67 Fed. Reg. 80186. On June 24, 2005, the
United States Court of Appeals for the D.C. Circuit vacated some of the rule changes, including exemptions for modifications
to certain “clean units” and modifications that qualify as “pollution control projects.” New York v. EPA, 413 F.3d 3 (D.C.
Cir 2005). The remaining rules, which remain in effect, consist of changes to the method for calculating the emissions
increase from a modification to an existing emissions unit and provisions for “Plantwide Applicability Limits” (PALs).
The determination of whether a modification to an existing unit will result in a significant emissions increase entails a
comparison between “baseline” (i.e. existing) emissions and future emissions after the modification is complete. (The
installation of a new unit is generally deemed to result in an increase equal to the unit’s potential to emit.) NSR reform
established a new method for determining baseline emissions and a new option for determining future emissions for
modifications to existing units.
Under pre-NSR Reform rules, baseline emissions were generally calculated using the actual emissions for the two-year
period immediately preceding the proposed change. 67 Fed. Reg. 80188. As EPA has noted, regulated industries complained
that this method provided only “limited ability to consider the operational fluctuations associated with normal business
cycles.” 67 Fed. Reg. 80191. The NSR Reform amendments therefore allow the use of any consecutive 24-month period
during the ten-year period prior to the change to establish baseline actual emissions. (A five- year period is used for EGUs.)
Before NSR Reform, an existing unit’s future, post-modification emissions were normally deemed to equal the unit’s
potential to emit (PTE). The definition of PTE assumes that a unit “will operate at its full capacity year round,” unless the
source’s permit includes “enforceable restrictions on the unit’s operation.” This was problematic, because “using PTE as a
measure of post-change emissions automatically attributes all possible emissions increases to the change.” In many cases,
however, the unit might “function essentially as it did before the change” and produce no increase or a less-than-significant
increase in actual emissions. 67 Fed. Reg. 80193-94.
After NSR Reform, a source’s owner or operator may now elect to use an existing unit’s “projected actual emissions,” rather
than its PTE, to determine future emissions. Unlike PTE, a unit’s projected actual emissions take into account historical
operational data and exclude emissions that could have been accommodated before the modification.
According to EPA, this new test for calculating the emissions increase from a modification to an existing unit, known as the
“actual-to-projected-actual” test, will produce benefits for regulated industries, the environment and state and local agencies:
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By allowing you [i.e., regulated entities] to use today’s new version of the actual-to-projected-actual applicability
test to evaluate modified existing emissions units, we expect that fewer projects will trigger the major NSR
permitting requirements. Nonetheless, we believe that the environment will not be adversely affected by these
changes and in some respects will benefit from these changes. The new test will remove disincentives that
discourage sources from making the types of changes that improve operating efficiency, implement pollution
prevention projects, and result in other environmentally beneficial changes. Moreover, the end result is that State
and local reviewing authorities can appropriately focus their limited resources on those activities that could cause
real and significant increases in pollution. 67 Fed. Reg. 80192.
The NSR Reform rule also provides that if there is a “reasonable possibility” that modifications to existing emissions units
will produce a significant emissions increase of a regulated NSR pollutant, and the owner or operator elects to use the actual-
to-projected-actual test, the modifications will be subject to monitoring, recordkeeping and reporting obligations.
The initial NSR Reform rule did not define “reasonable possibility.” The court in New York v. EPA held that without a
definition or other clarification, the rule failed to provide regulated entities or agencies adequate notice of when these
obligations are triggered. In response, EPA issued amendments to its major NSR rules defining the term. 72 Fed. Reg. 72607
(Dec. 12, 2007). Although EPA subsequently granted a petition to reconsider the definition, it did not stay the provision,
which therefore remains in effect.
The other major element of NSR Reform is the PAL, which allows major sources to avoid major NSR by accepting and
complying with a source-wide cap on emissions. PALs are set for each regulated NSR pollutant at a level equal to baseline
actual emissions plus the significant level for the pollutant. Baseline actual emissions are calculated in the same way as
described above for calculating emission increases from modifications to existing emission units. A source may generally
make any changes it wants without triggering major NSR, so long as plantwide emissions after the change remain below the
PAL. PALs last for ten years and are renewable.
EPA believes that regulated entities “will benefit from the PAL option because [they] will have increased operational
flexibility and regulatory certainty, a simpler NSR applicability approach, and fewer administrative burdens.” 67 Fed. Reg.
80206. Based on a review of six flexible permit pilot projects, EPA concluded that the environment would also benefit.
According to the agency, “PALs will over time tend to shift growth in emissions to cleaner units, because the growth will
have to be accommodated under the PAL cap.” 67 Fed. Reg. 80207.
Since the last Maricopa County update, EPA also has made numerous revisions to the NAAQS. The NAAQS are not
technically part of EPA’s NSR regulations, but in order to be approvable, a state NSR program must allow for enforcement of
the current version of these standards. See, e.g., 40 CFR 51.166(k)(1). Maricopa County must also update Rule 510 to reflect
the revised NAAQS.
Finally, EPA has made numerous other revisions that must be included in the Maricopa County program, such as the
adoption of PM2.5 increments and significant impact levels and significant monitoring concentrations for PM2.5.
Discussion About This Rulemaking
Consistent with the Maricopa County obligation under A.R.S. § 49-480(B), the department is proposing to adopt NSR
amendments that are substantially identical to the ADEQ and EPA NSR programs for major sources and amendments that
generally impose no greater procedural burden than ADEQ’s procedures for minor sources. However, due to long-standing
nonattainment area federal requirements, Maricopa County’s permitting thresholds are lower than ADEQ’s permitting
thresholds. 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 ADEQ for similar sources unless it demonstrates compliance with the applicable requirements of A.R.S. §49-112.
Under § 49-112(A), the county may adopt a rule that is more stringent than or in addition to a provision of A.R.S. Title 49 or
an ADEQ rule under specific conditions including peculiar local conditions, necessary to prevent a significant threat to public
health or environment, or required under a federal statute or regulation.
Revisions to Maricopa County Major NSR Program
EPA’s major NSR regulations are quite detailed and restrictive. They establish a specific body of “corresponding federal law
that addresses the same subject matter” as the major NSR amendments. The amendments included in the ADEQ NSR
rulemaking consisted of those required under HB 26171 and ensured that the major NSR program amendments were
consistent with and no more stringent than the corresponding EPA regulations. Consistent with that obligation, Maricopa
County is proposing to adopt major NSR amendments that incorporate by reference most of the federal rules. Incorporation
1 HB 2617 which became law on July 29, 2010, required that ADEQ as set forth in A.R.S. § 49-104(A):
17. Unless specifically authorized by the legislature, [the department shall] ensure that state laws, rules, standards, permits, variances
and orders are adopted and construed to be consistent with and no more stringent than the corresponding federal law that addresses the
same subject matter. This provision shall not be construed to adversely affect standards adopted by an Indian tribe under federal law.
Laws 2010, Ch. 309, § 14.
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by reference will result in rules substantially identical to the ADEQ rulemaking described above. Specifically, these proposed
provisions will eliminate a provision from the existing definition of major source because it was more stringent than the
corresponding federal definition. In addition, the incorporation by reference of the federal definitions would be substantially
identical to the sense, meaning, and effect of ADEQ’s definitions as required by A.R.S. § 49-471.08(B).
In Rule 240, the department is proposing to incorporate by reference 40 CFR 51.155(a)(1), which includes the definition of
“net emissions increase”. In the incorporated definition of “net emissions increase”, the department is proposing to replace
“reasonable period” with “between the date five years before construction on the date the particular change commences, and
the date that the increase from the particular change occurs.” The current proposed change is consistent with ADEQ’s NSR
rules R18-2-101(88) (Definition of “Net Emissions Increase”). At the request of Stakeholders, the department is also
soliciting comments on two other options for defining “reasonable period” in the definition of “net emissions increase”. First,
the language in Rule 240, Section 304.1(a)(3) would define the term “reasonable period” to read “between the date five (5)
years before submitting a permit application or commencing construction of the particular major modification, whichever is
sooner, and the date that the increase from the particular major modification occurs”. Second, the language in Rule 240,
Section 304.1(a)(3) would define the term “reasonable period” to read “between the date seven years before construction on
the date the particular change commences, and the date that the increase from the particular change occurs.”
In addition, Maricopa County nonattainment area plans do not rely upon the major source NSR program as a control measure
to achieve emission reductions and reach attainment as expeditiously as practicable and thus a change in the NSR program
will not interfere with any applicable requirement concerning attainment and reasonable further progress. See EPA’s
approval of the Maintenance Plan and Redesignation Requests for the 8-hour carbon monoxide standard (70 FR 11553,
March 9, 2005),1-hour ozone standard (70 FR 34362, June 14, 2005) and 1997 8-hour ozone standard (79 FR 55645,
September 17, 2014). Further, major or minor sources that propose to become major remain subject to the “source
obligation” provisions of 40 C.F.R. § 52.21(r)(4) incorporated by reference in Rule 240, Sections 305.1 and 304.7.
Stakeholders and EPA have asked the department to clarify how requests for major NSR permit extensions are treated and
how the department will implement 40 CFR 51.307 regarding visibility. Regarding action on applications and notification
requirements, the department intends to implement provisions consistent with the EPA’s “Guidance on Extension of
Prevention of Significant Deterioration (PSD) Permits Under 40 CFR 52.21(r)(2)”, January 31, 2014. Regarding visibility,
significant portions of the Maricopa County’s urbanized area lie within 100 kilometers (km) of the four mandatory Federal
Class I areas: Superstition, Mazatzal, Sierra Ancha and Pine Mountain Wilderness areas. Consistent with Rule 240, the
department provides the federal land manager (FLM) written notification of all proposed new major sources or major
modifications within 30 days of receipt of and at least 60 days prior to a public hearing by the department on the application
for a permit to construct. This notice includes the visibility analysis submitted as required under Rule 240 Sections 302.3,
304.18, and 305.1(b) and (d). In accordance with EPA and FLM guidance documents, the process for determining whether a
new major source or major modification that “may affect” visibility will cause an “adverse impact on visibility” involves two
separate determinations. Initially, a source must determine whether the source would cause “visibility impairment” based on
how visibility would change from what would have existed in absence of any human-caused pollution. For this initial
determination, the above guidance allows a source located or proposing to locate greater than 50 km from a Class I area to
choose to utilize the Q/D ≤ 10 initial screening criteria in accordance with the FLA 2010 guidance document to determine
whether further visibility analysis is required. The second determination considers whether the source that causes “visibility
impairment” will have an adverse impact on visibility. This determination requires a more holistic evaluation of various
factors affecting visibility, potentially including current visibility conditions and whether the State is on track toward
improving visibility.
Maricopa County Minor NSR Requirements
The proposed rule amendments relating to minor NSR included in this rulemaking are designed to address a lack of explicit
procedures designed “to assure that national ambient air quality standards are achieved,” as required by CAA § 110(a)(2)(C).
Maricopa County’s current minor source permitting rules require the inclusion of “[e]nforceable emission limitations and
standards, including operational requirements and limitations that ensure compliance with all applicable requirements.” Rule
220, Section 302.2. They therefore satisfy the requirement in EPA’s minor NSR rules to assure that minor sources do not
violate “applicable portions of the control strategy.” The proposed rule amendments specifically include requirements to
conduct an ambient air quality assessment if the Control Officer determines the source may interfere with attainment or
maintenance of the NAAQS and for the Control Officer to deny the permit if the assessment demonstrates that the source will
interfere with attainment or maintenance of the NAAQS. Another proposed rule amendment adds procedures related to stack
heights, including good engineering practice (GEP) stack height provisions as required by 40 CFR 51.164 in Rule 200. The
department does not believe that many, if any, minor sources will trigger the stack height requirements.
Maricopa County's permit rules for minor NSR impose no greater procedural burden than procedures for the review,
issuance, revision and administration of permits issued by the State. However, Maricopa County's rules and procedures
contain requirements specific to nonattainment area status, increment consumption analysis and impacts on nearby
nonattainment areas. These requirements result in permit conditions that address the source's proximity to the PM10 and
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ozone nonattainment areas, specific atmospheric and geographical conditions found at the source's location, control
technology provisions required by the CAA for nonattainment areas, and other control measures adopted into various
nonattainment SIPs for Maricopa County. Specifically, various SIPs for Maricopa County have required the adoption of
reasonably available control technology (RACT), best available control technology (BACT), and most stringent measures
(MSM) as required by CAA §§ 172, 182, 188, and 189.
As a result of long-standing nonattainment classifications for ozone and particulates, Maricopa County has existing
permitting thresholds that are lower than ADEQ’s in order to address the emissions sources specific to the county that
contribute to nonattainment and are subject to the county’s numerous source-specific emission control rules. Based on an
analysis of 2011 Periodic Emission Inventories (see “2014 Analysis of 2011 Periodic Emissions Inventory to Support
Permitting Thresholds in NSR Rulemaking”), the department estimates the contribution from permitted area sources as a
percentage of total emissions has been reduced to 2.7% for PM10, 10% for VOC, 4.6% for NOx and 0.5% for CO. In this
action, the county proposes to retain the current permitting threshold of total uncontrolled emissions of less than three pounds
VOC or PM10 per day and less than 5.5 pounds of any other regulated air pollutant per day but convert all thresholds from
pounds per day to tons per year. The permitting thresholds are proposed to be:
Pollutant Maximum Capacity To Emit Emission
Rate In Tons Per Year
(TPY)
PM2.5 (primary emissions only; levels for precursors are set below) 0.5
PM10 0.5
SO2 1.0
NOx 1.0
VOC 0.5
CO 1.0
Pb 0.3
Single HAP (other than Pb) 0.5
Total HAPs 1.0
Any other regulated air pollutant 1.0
Given the lower permitting thresholds and the number of source-specific emission control rules in place to address county
nonattainment areas, Maricopa County also proposes to define permitting thresholds that would trigger minor NSR
modifications as follows:
Pollutant Maximum Capacity To Emit Emission
Rate
In Tons Per Year (TPY)
PM2.5 (primary emissions only; levels for precursors are set below) 7.5
PM10 7.5
SO2 20
NOx 20
VOC 20
CO 50
Pb 0.3
The county also has different existing public review procedures than ADEQ due to these circumstances. The county
procedures were adopted in March, 2000 following a Stakeholder process with input from both regulated sources and non-
governmental organizations. The county procedures require the following:
- Posting the receipt of all applications on the department’s website once a week as they are received,
- Allowing the public to request a public hearing on any application posted to the website at any time after the initial post,
- Providing a formal 30-day public notice published in the newspaper and posted online for larger, more environmentally
significant sources, and
- Once a month, publishing in a newspaper and posting online a list of permits issued that month.
In this rulemaking, the department also proposes to convert the public participation thresholds to the following tons per year
thresholds from the current triggers that rely on Rule 280 fee tables:
Pollutant Public Notice Threshold TPY Public Notice Threshold TPY
(New Or Permit Renewals (PTE To PTE Emission Increase)
PTE)
VOC 25 25
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NOx 25 25
SO2 25 25
PM10 7.5 7.5
PM2.5 (primary emissions only; 5.0 5.0
levels for precursors are set above)
CO 50 50
Pb 0.3 0.3
Any Single HAP 5.0 5.0
Total HAPs 12.5 12.5
The public notice thresholds are approximately equivalent to the existing source type specific thresholds and are less than
half of the major sources thresholds except for carbon monoxide. Based on the current profile of permits (see “2014 Public
Participation Thresholds Justification”), the department estimates approximately 73.1% of area source individual and general
permits will undergo public notice. The remaining small area sources that will not be subject to public notice are less
environmentally significant and account for less than 2% of the total emissions inventory for each pollutant.
Proposed Amendments to Match Rule Language Found In ADEQ’s NSR Rules
The department is proposing amendments in the following rules to match rule language found in ADEQ’s NSR rules: Rule
210 (Title V Permit Provisions), Rule 220 (Non-Title V Permit Provisions), Rule 241 (proposed new title: Minor New Source
Review (NSR)), Rule 500 (Attainment Area Classification) and Rule 510 (Air Quality Standards).
The following sections in Rule 210 are proposed to be revised:
- Section 200 (Definitions-Introductory Statement): To clarify the applicability of definitions specific to Rule 210 and to
Rule 100 (General Provisions And Definitions).
- Section 301.2 (Standard Application Procesisng Procedures): To delete text re: a timely application for the initial Phase
II acid rain requirement in response to Stakeholder and EPA concerns.
- Sections 301.8(b)(3) and (5) (Action on Application): To add timeframe for EPA (the Administrator) to act on a permit
application that is required to be submitted to the EPA (the Administrator) in response to Stakeholder and EPA concerns.
- Sections 301.8(f) and (h) (Action on Application): To delete text re: the acid rain program in response to Stakeholder and
EPA concerns. To delete text re: the publishing of a proposed permit decision within nine months of receipt of a
complete application in response to Stakeholder and EPA concerns.
- Section 301.9 (Requirement for a Permit): To add text re: the source’s obligation to obtain a permit revision before
making a modification to the source in response to Stakeholder and EPA concerns.
- Section 403.1 (Source Changes Allowed Without Permit Revisions): To add additional gatekeeper for changes eligible
for minor permit revision.
- Section 403.8 (Source Changes Allowed Without Permit Revisions): To delete text re: the Control Officer requiring a
permit to be revised (outdated provision); is addressed in Section 405.8.
- Section 406.6 (Significant Permit Revisions): To delete text re: the Control Officer processing the majority of significant
permit revision applications within nine months of receipt (outdated provision).
- Sections 408.2 and 408.7 (Public Participation): To add text re: the Control Officer providing public notice of receipt of
complete applications for major modifications to major sources. To add text re: the Control Officer providing at least 30
days from the date of the first notice for public comment to receive comments and requests for a hearing. To add text re:
the Control Officer making available responses at the time a final proposed permit is submitted to the EPA.
The following sections in Rule 220 are proposed to be revised:
- Sections 301.3(a) and (b) (A Timely Permit Application): To clarify what a timely permit application is for a source that
becomes subject to the permit program as a result of a change in the regulation in response to Stakeholder and EPA
concerns.
- Section 301.6(b)(4) (Action on Application): To add timeframe for EPA (the Administrator) to act on a permit
application that is required to be submitted to the EPA (the Administrator) in response to Stakeholder and EPA concerns.
- Section 301.7 (Permit Application Processing Procedures): To add text re: the source’s obligation to obtain a permit
revision before making a modification to the source in response to Stakeholder and EPA concerns.
- Sections 407.1, 407.2, and 407.3 (Public Participation): To clarify when the Control Officer must provide public notice
and an opportunity for public comment and what permit applications must be published on the Internet and what permit
applications must be published in a newspaper.
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- Section 407.7 (Public Participation): The department already satisfies this requirement of providing notice for changes
requiring non-minor permit revisions to make a change in fuel, to make a change that relaxes monitoring, and to make a
change that will require case-by-case determinations for a monitoring requirement by publishing a notice in the
newspaper and on the department’s website.
The following sections in Rule 241 are proposed to be revised:
- Section 304 (BACT Required): To delete lbs/day threshold limits
- Section 305 (RACT Required): To delete lbs/day threshold limits
The following section in Rule 500 is proposed to be revised:
- Rule 500 is proposed to be repealed, because the information in the rule is being incorporated by reference in Rule 240.
The following sections in Rule 510 are proposed to be revised:
- Section 200 (Definitions-Introductory Statement): To clarify the applicability of definitions specific to Rule 510 and to
Rule 100 (General Provisions And Definitions).
- Section 301 (Standards-Particulate Matter-2.5 Microns or Less (PM2.5)): To update particulate matter ambient air quality
standards to reflect latest ADEQ and EPA revisions.
- Section 302 (Standards-Particulate Matter-10 Microns or Less (PM10)): To update particulate matter ambient air quality
standards to reflect latest ADEQ and EPA revisions. To delete annual PM10 standard to reflect latest ADEQ revisions,
which were made as required by House Bill 2617.
- Sections 303.1(c) and (d) (Sulfur Oxides (Sulfur Dioxide)): To update sulfur dioxide ambient air quality standards to
reflect latest ADEQ and EPA revisions.
- Section 304 (Ozone): To update ozone ambient air quality standards to reflect latest ADEQ and EPA revisions.
- Section 306 (Nitrogen Oxides (Nitrogen Dioxide)): To update nitrogen dioxide ambient air quality standards to reflect
latest ADEQ and EPA revisions.
- Section 307 (Lead): To update lead ambient air quality standards to reflect latest ADEQ and EPA revisions.
- Section 308 (Pollutant Concentration Determinations): To update pollutant concentration measurement methods.
Major NSR:
The department is proposing to incorporate portions of the federal nonattainment NSR rule requirements into Maricopa
County Air Pollution Control Regulations Rule 240 by incorporating the federal requirements by reference. The proposed
amendments to the department’s major NSR program include:
- The determination of whether a modification to an existing unit will result in a significant emissions increase, which
entails a comparison between “baseline”, i.e., existing emissions and future emissions after the modification is complete.
- The allowance of the use of any consecutive 24-month period during the ten-year period prior to the change to establish
baseline actual emissions (a five-year period for electric generating units).
- The allowance to use an existing unit’s “projected actual emissions,” rather than its potential to emit (PTE), to determine
future emissions. Unlike PTE, a unit’s projected actual emissions take into account historical operational data and
exclude emissions that could have been accommodated before the modification. This new test for calculating the
emissions increase from a modification to an existing unit, known as the “actual-to-projected” test, will produce benefits
for regulated industries, the environment and state and local agencies. If there is a “reasonable possibility” that
modifications to existing emissions units will produce a significant emissions increase of a regulated NSR pollutant and
the owner or operator elects to use the actual-to-projected-actual test, the modifications will be subject to monitoring,
recordkeeping and reporting obligations.
- Plantwide applicability limitations (PALs). PALs allow major sources to avoid major NSR by accepting and complying
with a source-wide cap on emissions. PALs are set for each regulated NSR pollutant at a level equal to baseline actual
emissions plus the significant level for the pollutant. A source may generally make any change it wants without
triggering major NSR, so long as plantwide emissions after the change remain below the PAL. PALs last for ten years
and are renewable.
- The allowance of limited interpollutant emission offsets for precursor pollutants on a case by case basis, except for PM10
and PM2.5. Any interpollutant emission offsets used at a major stationary source must receive written approval by EPA.
As EPA has approved a demonstration that PM10 precursors do not contribute significantly to PM10 violations in
Maricopa County (67 FR 48734, July 25, 2002), interpollutant offsets are not allowed between PM10 and PM10
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precursors. In addition, interpollutant offsets between PM2.5 and PM2.5 precursors are not allowed unless modeling has
been used to demonstrate appropriate PM2.5 interpollutant offset ratios as approved in a PM2.5 Attainment Plan.
Minor NSR:
The department is proposing amendments in the following rules to address Minor NSR: Rule 200 (Permit Requirements),
Rule 220 (Non-Title V Permit Provisions), Rule 230 (General Permits), Rule 241 (proposed new title: Minor New Source
Review (NSR)), Appendix D (List Of Insignificant Activities), and Appendix E (List Of Trivial Activities). The amendments
include the following:
- Retention of existing permitting exemption thresholds but conversion of default emission-based provision from lbs/day
to an annual quantity.
- Use the emission-based thresholds for minor NSR modification threshold.
- Current permitting thresholds are proposed to be retained. Current permitting thresholds are for any regulated air
pollutant: CO, NOx, SOx (measured as SO2), ozone, VOC, particulates, air contaminant subject to New Source
Performance Standard (NSPS)), and HAPs. Current permitting thresholds are: VOC-0.5 tons per year (tpy); CO-1.0 tpy;
NO2 or NOx-1.0 tpy; SO2-1.0 tpy; lead (Pb)-0.3tpy; PM10-0.5 tpy.
 Definitions are proposed to be added to Rule 100:
 “Minor NSR modification” is a new term and is similar to ADEQ’s definition of “permitting exemption
threshold”. (The definition of “modification” is proposed to be revised to be consistent with ADEQ’s NRS rules
R18-2-101(80) and the definition of “major modification” is proposed to be revised to be consistent with ADEQ’s
NSR rules R18-2-101(74). The definition of “modification” defines activities differently from the definition of
“major modification” and the definition of “minor NSR modification” because the definition of “modification”
applies to Title V and operating permit rules. The term “modification” as used in Rule 241 refers specifically to
minor NSR modification.)
 “Permitting threshold” is a new term but includes the current permitting thresholds.
 “Public notice threshold” is a new term; thresholds are lower than significance levels.
 “Regulated minor NSR pollutant” and “Regulated NSR pollutant” are new terms and are similar to ADEQ’s
terms/definitions.
- Retention of Best Available Control Technology (BACT) and Reasonably Available Control Technology (RACT)
control technology requirements in Rule 241.
- Requirement of an air quality impact assessment if there is reason to believe emissions resulting from a new or modified
source undergoing Minor NSR might cause or contribute to an exceedance of the NAAQS.
- Retention of the current alternative forms of public participation for smaller minor sources and small modifications that
will not require formal publication of a notice in a newspaper.
The amendments proposed by this rulemaking update the department’s NSR rules, clarify requirements, and provide
compliance with the Federal NSR program Section 110(a) (2) (C) of the federal Clean Air Act (CAA).
7. Demonstration of compliance with A.R.S. § 49-112:
Under A.R.S. § 49-479(C), a county may not adopt a rule or ordinance that is more stringent than the rules adopted by the
Director of the Arizona Department of Environmental Quality (ADEQ) for similar sources unless it demonstrates compliance
with the applicable requirements of A.R.S. §49-112.
§ 49-112 County regulation; standards
§ 49-112(A)
When authorized by law, a county may adopt a rule, ordinance or other 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 conditions are met:
1. The rule, ordinance or other regulation is necessary to address a peculiar local condition.
2. There is credible evidence that the rule, ordinance or other 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.
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(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 other regulation is
equivalent to federal statutes or regulation.
3. Any fee or tax adopted under the rule, ordinance or other regulation will not exceed the reasonable costs of the county to
issue and administer that permit or plan approval program.
§ 49-112(B)
When authorized by law, a county may adopt rules, ordinances or other 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 other regulation that does not exceed the reasonable costs of the county
to issue and administer that permit or plan approval program.
Maricopa County fails to meet the National Ambient Air Quality Standards for both ozone and particulates. While currently
classified as a “marginal” ozone nonattainment area, the county recently failed to meet 2008 8-hour ozone standard by the
marginal area attainment date and anticipates EPA will issue a notice proposing to re-classify the area to “moderate”.
Further, a portion of the county was classified as a serious ozone nonattainment area under the previous 1-hour ozone
standard requiring the county to continue to maintain the measures and requirements that allowed the county to attain that
standard. Currently, a portion of Maricopa County and Apache Junction in Pinal County is designated serious nonattainment
for the PM10 24-hour standard. This is the only serious PM10 nonattainment area in Arizona. Maricopa County's permit rules
for these programs are substantially identical to or impose no greater procedural burden than procedures for the review,
issuance, revision and administration of permits issued by the State. However, Maricopa County's rules and procedures
contain requirements specific to nonattainment area status, increment consumption analysis and impacts on nearby
nonattainment areas. These requirements result in permit conditions that address the source's proximity to the PM10 and
ozone nonattainment areas and specific atmospheric, geographical conditions found at the source's location, and control
technology provisions required by the CAA for nonattainment areas, and other control measures adopted into various
nonattainment SIPs for Maricopa County. Specifically, various SIPs for Maricopa County have required the adoption of
reasonably available control technology (RACT), best available control technology (BACT), and most stringent measures
(MSM) as required by CAA §§ 172, 182, 188, and 189.
The department complies with A.R.S. § 49-112 in that the proposed amendments to 1) the department’s major source NSR
rules are not more stringent than or in addition to a provision of Title 49 or rule adopted by the director or any board or
commission authorized to adopt rules pursuant to Title 49, 2) the department’s minor source rules address the peculiar local
conditions in Maricopa County and address long-standing federal requirements for nonattainments areas, and 3) the proposed
amendments to the department’s NSR rules are authorized under A.R.S. Title 49, Chapter 3, Article 3 and consequently are
not in lieu of a state program.
8. Reference to any study relevant to the rule that the department reviewed and either proposes to rely on in its
evaluation of or justification for the rule, where the public may obtain or review each study, all data underlying each
study, and any analysis of each study and other supporting material:
“2014 Analysis of 2011 Periodic Emissions Inventory to Support Permitting Thresholds in NSR Rulemaking”
“2014 Public Participation Thresholds Justification”
Documents are available at the Maricopa County Air Quality Department, 1001 North Central Avenue, Suite #125, Phoenix,
Arizona 85004
9. Showing of good cause why the rule is necessary to promote a statewide interest if the rule will diminish a previous
grant of authority of a political subdivision:
Not applicable
10. Summary of the economic, small business, and consumer impact:
The following discussion addresses each of the elements required for an economic, small business and consumer impact
statement (ESBCIS) as required by A.R.S. § 49-471.05 and prescribed in A.R.S. § 41-1055, subsections A, B and C.
An identification of the rulemaking.
The rulemaking addressed by this ESBCIS is the adoption of amendments designed to bring the department’s NSR rules into
conformance with federal requirements for minor NSR and incorporate recent changes to EPA’s major NSR regulations. In
particular, this ESBCIS covers amendments to the following existing rules and appendices: Rules 100, 200, 210, 220, 230,
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240, 241, 500, 510, 600, and Appendices D and E. These rule changes are described in detail in Item 6 of this Draft Notice
of Final Rulemaking.
Two specific elements of the NSR amendments are addressed in the ESBCIS:
1. New and amended ambient standards that EPA has adopted since the department last amended Rule 510 and that may
need to be addressed in New Source Review (NSR) and Prevention of Significant (PSD) applications and permitting
decisions. Specifically: the more stringent annual and 24-hour National Ambient Air Quality Standards (NAAQS) for
PM2.5, PM2.5 increments, the more stringent eight-hour NAAQS for ozone, the new one-hour NAAQS for sulfur dioxide
and nitrogen dioxide. These changes may result in increased compliance costs for sources and minor increased
administrative costs for the department.
2. NSR reform amendments. These changes will reduce compliance costs and will have a mixed effect on the department’s
administrative costs.
The remaining changes to major NSR are technical in nature and should have little, if any, economic impact on the agency,
businesses or consumers.
An identification of the persons who will be directly affected by, bear the costs of or directly benefit from the
rulemaking.
In general terms, the persons who will be directly affected by and bear the costs of the proposed rulemaking will be
businesses that construct or modify stationary sources that are subject to major or minor NSR. The emissions thresholds for
sources and modifications subject to major and minor NSR are described in detail in Item 6 of this Draft Notice of Final
Rulemaking.
The types of business operations subject to the department’s major NSR program typically include natural gas-fueled power
plants, petroleum products terminals, landfills, metal processing, and manufacturers of reinforced plastics, expandable foam,
wood furniture, steel products, and aircraft engine and parts. Major sources tend to be large facilities operated by publicly
owned corporations and employing hundreds or thousands of employees.
As discussed in Item 6 of this Draft Notice of Final Rulemaking, major sources are potentially subject to minor as well as
major NSR. Minor NSR may also apply to smaller business operations or operations that, although substantial in scale, tend
to have emissions below the major source thresholds. These include rock quarrying and crushing operations, concrete batch
plants, asphalt plants, semiconductor manufacturers, chemical manufacturers, crematories, dry cleaners, landfills, wood
product manufacturers, commercial printers and publicly owned waste water treatment facilities.
The above list is not exhaustive. Any business that engages in pollutant emitting activities is potentially subject to NSR.
Typical pollutant-emitting activities include fuel combustion to produce energy or as part of a process, the use of solvents,
the application of surface coatings (such as paints and varnishes), the storage of fuels and other organic liquids and the
handling of materials likely to give rise to airborne dust. Tailpipe emissions from mobile sources are not considered in
determining NSR applicability.
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 rulemaking.
As required by A.R.S. § 49-480(D), the hourly rate for billable permit actions under Rule 280 (Fees) Sections 301.1 and
302.1 has been set to reflect the department’s cost of processing permit applications (14 A.A.R. 1767, May 9, 2008).
Therefore, in assessing the costs to the department of conducting the permitting and administrative activities required by this
rule, the department has assumed that the cost per additional hour of employee time is equal to the current hourly rate of
$150.00.
Major NSR
The department’s costs of implementing the additional major NSR requirements will likely be minimal. In fact
implementation of NSR reform may result in a net cost savings for the department.
One element of the major NSR amendments that will increase the department’s costs of administering the air quality permit
program is the incorporation of the new ambient standards: the PM2.5 NAAQS and PM2.5 increments, the one-hour sulfur
dioxide NAAQS and the one-hour nitrogen dioxide NAAQS. The air quality impact analysis for major NSR permit
applications addressing these pollutants will be somewhat longer and more complex than under current rules and will
therefore require additional review time by the department’s permit engineers. The ozone and lead NAAQS amendments, on
the other hand, constitute an increase in the stringency of existing standards and should not result in any modeling or review
time beyond that already required. The department has received and processed three major NSR applications in the past eight
years. Most major NSR permit applications will require an air quality analysis for the new ambient standards. The
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department’s Permit Engineering Division estimates that the additional review time will range from five to ten hours. The
total annual cost to the agency per year for the additional major NSR requirements will therefore range from $750.00 to
$1,500.00 ($150.00 X 5 hours; $150.00 × 10 hours). Under Rule 280 (Fees), Section 301.1, the permit applicant will
ultimately be required to reimburse the department for this cost as part of its permit fee.
The impact of NSR reform on the department’s air quality permitting costs is difficult to gauge. NSR reform includes
elements that could either increase or reduce the costs of administering the major NSR program. The department believes that
on balance, the cost savings of NSR reform will outweigh whatever additional costs will be imposed. This is consistent with
EPA’s conclusion that NSR reform would allow state permitting authorities to “focus their limited resources on those
activities that could cause real and significant increases in pollution.” 67 Fed. Reg. 80186, 80192 (2002).
Minor NSR
The department’s Minor NSR program as proposed would apply to all new sources with the potential to emit any regulated
minor NSR pollutant in an amount equal to or greater than the permitting threshold defined in Rule 100 and not subject to
major source requirements under Rule 240 and any existing permitted source that increases its potential to emit any regulated
minor NSR pollutant in an amount equal to or greater than the minor NSR modification threshold (defined in Rule 100).
As discussed in Item 6 of this Draft Notice of Final Rulemaking, the proposed amendments to change from daily to annual
permitting threshold limits will enable less burdensome and streamlined record keeping requirements. The change to annual
threshold limits from per day limits reduces the record keeping burden, particularly for small sources, who would be more
likely than larger sources to have emissions that fall near the threshold limits and would be required to maintain
documentation of emissions levels.
Based on experience in administering the existing permit program, the department’s Permit Engineering Division estimates
that it will process approximately 75 applications for permits or permit revisions subject to minor NSR per year. The Permit
Engineering Division also estimates that on average the additional time for processing the minor NSR components
(applicability and air quality impact analyses) of a permit or permit revision application will be 2 hours per application for
screening model for ambient air quality assessment and 5 hours per application for reviewing refined modeling performed by
the source. The Permit Engineering Division further estimates that the department will perform a screening model for the air
quality impact assessment on approximately 5% of the permit applications and will review the refined modeling performed
by the source on approximately 1% of the permit applications. Therefore, the department estimates the additional annual cost
to the department for the minor NSR components of a permit or permit revision will be approximately $4,300.00 (4
applications × 2 hours × $150.00 per hour = $1,200.00) + (2 applications × 7 hours × $150.00 per hour = $3,100.00).
Additional Cost to the Department for NSR Amendments:
The estimated additional annual cost to the department for the NSR amendments is approximately $35,000.00:
$750.00 to $1,500.00 for additional major NSR costs + $33,750.00 for minor NSR costs = $34,500.00 to $35,250.00
Under Rule 280 (Fees), Sections 301.1 and 302.1, the permit applicant will ultimately be required to reimburse the
department for this cost as part of its permit fee.
Other Agencies
Eighty-seven sources operated by state agencies require permits under the current program. They represent approximately 2%
of all department-permitted sources. All of these state-operated sources will bear the same costs of compliance described in
section (c) below for privately owned businesses.
(b) The probable costs and benefits to a political subdivision of this state directly affected by the implementation and
enforcement of the rulemaking
Four-hundred forty sources operated by political subdivisions require permits under the current program. They represent
approximately 10% of all department-permitted sources. All of these sources will bear the same costs of compliance
described in section (c) below for privately owned businesses.
(c) The probable costs and benefits to businesses directly affected by the rulemaking, including any anticipated effect
on the revenues or payroll expenditures of employers who are subject to the rulemaking.
Major NSR
As discussed in Item 6 of this Draft Notice of Final Rulemaking, the amendments to the department’s major NSR rules are
the minimum necessary to comply with federal requirements for the program. Even if the department failed to adopt these
amendments, they would ultimately apply to major sources in Maricopa County either through the adoption of a federal
implementation plan (FIP) by EPA under section 110(c) of the Clean Air Act (in the case of PSD) or the application of 40
CFR 51, Appendix S (in the case of nonattainment NSR). At best, a decision by the department not to adopt the major NSR
13

amendments would result in a temporary delay in their application to sources in Maricopa County, Arizona. A discussion of
the additional costs and benefits of the amended requirements at the county-level nevertheless follows.
The new and amended ambient standards incorporated by this rule may result in the imposition of three types of additional
costs on applicants for major NSR permits.
First, a new major source or major modification with significant emissions of any of the pollutants subject to a new ambient
standard (the PM2.5 increments and PM2.5 NAAQS or the one-hour sulfur dioxide or nitrogen dioxide NAAQS) will be
required to conduct additional modeling to demonstrate compliance with these standards. The department estimates that one
additional model run for each major NSR applications will be required. The Arizona Department of Environmental Quality
(ADEQ) estimated in their NSR Notice of Final Rulemaking (18 A.A.R. 1542, July 6, 2012) based on information received
from an environmental consultant, that the cost of adding one model run to a refined model would be approximately
$8,000.00.
Second, applicants will be responsible for paying permit fees equal to the additional permit processing costs noted above due
to the major NSR amendments. As noted above, the estimated additional processing costs for major NSR will range from
$750.00 to $1,500.00.
Third, when modeling demonstrates an ambient impact resulting in non-compliance with an ambient standard (NAAQS or
increments), mitigation beyond the level of control technology already required by major NSR is necessary. The cost of
mitigation can be substantial but is highly dependent on the nature of the particular project and cannot be reliably estimated
for purposes of the ESBCIS. Moreover, because major NSR automatically requires a very stringent level of control (BACT
or LAER), mitigation is rarely necessary. Mitigation necessary to address non-compliance with any of the new standards
imposed in the major NSR amendments will be an even rarer occurrence. Thus, the major NSR amendments are unlikely to
result in additional mitigation costs.
The total estimated annual costs to sources subject to major NSR as a result of the rule amendments will range from
$8,750.00 to $9,500.00 ($8,000.00 + $750.00 to $1,500.00) plus the costs of mitigation, in the unlikely event it is required.
NSR reform, on the other hand, is likely to generate substantial savings for existing major sources that are potentially subject
to major NSR. The revised method for determining baseline emissions and the actual-to-projected-actual alternative for
determining the level of future emissions will make it easier for sources to demonstrate the inapplicability of major NSR.
Sources that obtain PALs will essentially be able to avoid subsequent major NSR for a 10-year period. The savings from
these reforms are difficult to estimate, but the department believes they will at least offset the additional costs described
above.
Minor NSR
As noted above, the department estimates that approximately 75 minor and major sources requiring permits or permit
revisions each year will be subject to minor NSR.
The minor NSR amendments may result in the imposition of three types of additional costs on applicants for major NSR
permits:
First, ADEQ estimated based on experience with contractors performing accelerated permitting services that the cost of
preparing the minor NSR components of a permit or permit revision application would average $4,000.00 (18 A.A.R. 1542,
July 6, 2012). The department’s Permit Engineering Division agrees with that estimate and therefore estimates annual
application preparation costs attributable to minor NSR at: 75 applications × $4,000.00 per application = $300,000.00.
Second, applicants will be responsible for paying permit fees equal to the additional permit processing costs as noted above
related to the minor NSR requirement for an air quality impact assessment. The department estimates above that screening
model may result in $300.00 of additional costs (2 hours × $150.00) and reviewing refined modeling performed by the source
may result in $1,050.00 of additional costs (7 hours × $150). Therefore, the department estimates annual additional permit
processing costs attributable to minor NSR at: 4 applications × $150 + 2 applications × $1,050 = $2,700.
Third, based on estimates provide by environmental consultants, ADEQ projected that the cost of running a refined model to
comply with minor NSR will be approximately $7,000 to $12,000 (18 A.A.R. 1542, July 6, 2012). The department’s Permit
Engineering Division agrees with that estimate and estimated above that 1% of minor NSR applicants will need to perform
refined modeling for the ambient air quality assessment. Therefore, the department estimates the additional annual cost
attributable to performing a refined model by the source ranges between $14,000 and $24,000 (2 applications × $7,000 vs. 2
applications × $12,000).
Lastly, the department anticipates no additional control costs will be incurred by sources as a result of minor NSR BACT or
RACT requirements because BACT or RACT is required under the department’s current permitting program. The minor
NSR amendments do have a new requirement for BACT or RACT for PM2.5 and lead; however, most sources that emit PM2.5
or lead also emit other pollutants such as NOx, CO or PM10 and these pollutants (NOx, CO or PM10) will trigger the BACT or
14

RACT analysis and generally the controls for these pollutants will also limit PM2.5 and lead. Currently, the department does
not have any lead sources that will trigger the requirement for a BACT or RACT determination for lead.
Permits issued by the department are valid for five years; therefore, the department estimates annual minor NSR permit
related costs for a source by dividing the total estimated cost by five years.
The department estimates the annual minor NSR costs for a source electing to have the department perform a screening
model at: $860.00. Whereas, the annual minor NSR costs for a source electing to perform a refined model is estimated to
range between $2,410.00 and $3,410.00.
- Annual minor NSR costs for source electing to have MCAQD perform a screening model:
$860 = (($4,000 permit application + $300 permit processing costs)/5 yrs.)
- Annual minor NSR costs for source electing to perform a refined model:
$2,410 = (($4,000 permit application prep + $1,050 permit processing + $7,000 refined modeling cost)/5 yrs.)
$3,410 = (($4,000 permit application prep + $1,050 permit processing + $12,000 refined modeling)/5 yrs.)
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 rulemaking.
The department does not believe that the additional costs to businesses subject to the amended NSR requirements, as
described above, will be substantial enough to deter the construction or expansion of business operations. Accordingly, there
should be no impact on private employment or on the employment of any political subdivisions subject to NSR.
The department estimates that approximately one new full-time employee will be needed to implement the additional
workload that will result from implementing minor NSR. A more precise estimate of the employment impact of minor NSR
will be included in the ESBCIS for the upcoming permit fee rule.
The amendments to major NSR include elements that will both reduce (NSR reform) and increase (new ambient standards)
agency workload. The department estimates that the net effect of the major NSR amendments on the agency’s employment
needs will be zero.
A statement of the probable impact of the rulemaking on small businesses.
(a) An identification of the small businesses subject to the rulemaking.
Under A.R.S. § 49-101(20):
“Small business” means a concern, including its affiliates, which is [1] independently owned and operated, which is [2]
not dominant in its field and which [3] employs fewer than one hundred full-time employees or which had gross annual
receipts of less than four million dollars in its last fiscal year. (Emphasis added.)
The department does not anticipate that this rulemaking will increase the number of sources subject to the department’s
NSR program.
(b) The administrative and other costs required for compliance with the rulemaking.
Small businesses will primarily incur the business costs described above for the minor NSR program.
(c) A description of the methods that the agency may use to reduce the impact on small businesses.
Establishing less costly compliance requirements in the rulemaking for small businesses.
The department’s existing general permit program which falls under its minor NSR program is a less costly alternative
currently available to many small businesses (e.g. dry cleaners, gas stations, surface coating operations, auto body shops,
etc.). The general permits are designed specifically with small businesses in mind. General permitted sources will not
incur the cost of an ambient air quality assessment as this would be done up front when the general permit is established
rather than when an authorization to operate is issued. Many small businesses currently required to obtain permits are
eligible for a general permit and are not required to get a Non-Title V permit. Thus, for some small businesses, the
general permit program is an existing and less costly alternative to the Non-Title V permit.
(d) The probable cost and benefit to private persons and consumers who are directly affected by the rulemaking.
Some businesses may pass some of the additional costs estimated above on to consumers. Because the amendments will
not substantially increase existing air quality compliance costs, the department anticipates that the impact will be
negligible.
A statement of the probable effect on state revenues.
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Since the costs of the amendments will be recoverable through air quality permit fees, there will be no net effect on state
revenues.
A description of any less intrusive or less costly alternative methods of achieving the purpose of the rulemaking.
As discussed above in Item 6 of this Draft Notice of Final Rulemaking, the department has adopted amendments that the
department believes to be the minimum necessary to comply with federal NSR requirements. No less intrusive or costly
alternatives are available.
11. Name and address of department personnel with whom persons may communicate regarding the accuracy of the
economic, small business, and consumer impact statement:
Name: Kathleen Sommer
Maricopa County Air Quality Department
Planning and Analysis Division
Address: 1001 N Central Avenue, Suite 125
Phoenix, Arizona 85004
Telephone: (602) 506-6010
Fax: (602) 506-6179
E-Mail: aqplanning@mail.maricopa.gov
12. Description of the changes between the proposed rules, including supplemental notices and final rules:
Since the Notice of Supplemental Proposed Rulemaking was published on October 2, 2015 (21 A.A.R. 2124), the
department is proposing the following additional amendments:
 Rule 100, Section 200.50 (Definition of “Existing Source”): In response to the Salt River Project Agricultural
Improvement and Power District’s (SRP’s) comments submitted on November 9, 2015, to change the definition of
“existing source” to “any source that is not a new source”
 Rule 100, Sections 200.64(c)(5) and (c)(6) (Definition of “Major Modification”): In response to the Salt River Project
Agricultural Improvement and Power District’s (SRP’s) comments submitted on November 9, 2015, to change the
definition of “major modification” so it is consistent with ADEQ’s NSR rules R18-2-101(74)
 Rule 100, Section 200.71(a)(2) (Definition Of “Minor NSR Modification”): To change “emissions” to “potential to emit”
in the phrase “Results in the potential to emit of a regulated minor NSR pollutant…”
 Rule 100, Section 200.71(c) (Definition of “Minor NSR Modification”): In response to SRP’s comments submitted on
November 9, 2015, to change “minor NSR threshold” to “minor NSR modification threshold”
 Rule 100, Section 200.71(f) (Definition of “Minor NSR Modification”): In response to SRP’s comments submitted on
November 9, 2015, to change the minor NSR modification thresholds to ½ significance levels
 Rule 100, Section 200.76 (Definition of “New Source”): In response to SRP’s comments submitted on November 9, 2015,
to change the definition of “new source” to “a source for which construction has not commenced before the effective date
of an applicable rule or standard to which a source is subject”
 Rule 100, Section 200.79 (Definition of “Physical Change”): In response to SRP’s comments submitted on November 9,
2015, to delete the definition of “physical change”
 Rule 100, Section 200.85 (Definition of “Owner And/Or Operator”): To change the term to “owner or operator”; to change
the term throughout all other rules in this rulemaking
 Rule 100, Section 200.106 (Definition of “Regulated NSR Pollutant”): In response to SRP’s comments submitted on
November 9, 2015, to change the definition to reference the reader to Rule 240 (Federal Major New Source Review
(NSR)); “regulated NSR pollutant” is defined in Rule 240 and is covered under the definition of “regulated minor NSR
pollutant” (defined in Rule 100, Section 200.105)
 Rule 100, Section 200.114(a) (Definition of “Significant”): To add “significant” before the phrase “net emissions increase”
 Rule 100, Section 200.114(a)(2) (Definition of “Significant”): In the first colum of the last row in the table, to delete
“regulated NSR” and to add “subject to regulation” in the phrase “Any pollutant subject to regulations not specifically
listed…”
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 Rule 200, Section 303.1 (Non-Title V Permit): To change “regulated NSR pollutants” to “regulated air pollutants”. By
definition, a hazardous air pollutant (HAP) is not a regulated NSR pollutant. Since HAPs are included as one of the
pollutants for which a Non-Title V permit is required, a Non-Title V permit is required for “regulated air pollutants” not
“regulated NSR pollutants”
 Rule 200, Section 303.2(a) (Non-Title V Permit): To add “solely” to the phrase “to obtain a permit soley because…” so it
is consistent with the text in Section 303.2(b)
 Rule 200, Sections 303.2(a) and (b) (Non-Title V Permit): In response to SRP’s comments submitted on November 9,
2015, to add text from proposed new Section 305.2 (Exemptions) and Section 305.3 (Exemptions) to clarify thresholds for
exemptions from obtaining a permit and thresholds for insignificant activities
 Rule 200, Section 305 (Exemptions): To restore an emissions limit above which any single or combination of activities is
required to obtain a permit; text is substantially identical to the sense, meaning, and effect of ADEQ’s NSR rules R18-2-
302(C)(1)
In the Notice of Proposed Rulemaking (21 A.A.R. 1302, July 31, 2015), the department proposed to add Rule 200, Section
305.4, which stated “The following sources shall be exempt from obtaining a permit…Insignificant activities, provided any
single or combination of insignificant activities have total uncontrolled emissions less than the permitting thresholds as
defined in Rule 100 of these rules.” The permitting thresholds were proposed to be: VOC-0.5 tons per year (tpy); CO-1.0
tpy; NO2 or NOx-1.0 tpy; SO2-1.0 tpy; lead (Pb)-0.3tpy; PM10-0.5 tpy. The definition of “insignificant activity” was
proposed as: “Any of the following activities: (a) Any activity, process, or emissions unit that is not subject to a source-
specific applicable requirement that emits no more than two tons per year of a regulated air pollutant…” and (b) through (i)
were the insignificant activities that were listed in Appendix D-List of Insignificant Activities and that were listed in Rule
200, Section 303.3(c)-activities that were exempt from obtaining a Non-Title V permit.
On August 31, 2015, the department received written comments from the Salt River Project Agricultural Improvement and
Power District (SRP). SRP’s comments included; “The proposed [permitting] thresholds are inconsistent with the current
MCAQD thresholds in Rule 100, Section 200.58 (proposed definition of “insignificant activity”), which states the
following: Insignificant Activity: For the purpose of this rule, an insignificant activity shall be any activity, process, or
emissions unit that is not subject to a source-specific applicable requirement, that emits no more than 0.5 ton per year of
hazardous air pollutants (HAPs) and no more than two tons per year of a regulated air pollutant, and this is either included
in Appendix D-List of Insignificant Activities of these rules or is approved as an insignificant activity under Rule 200-
Permit Requirements of these rules.”
In response to SRP’s comment regarding permitting thresholds, the department proposed (in a Notice of Supplemental
Proposed Rulemaking (21 A.A.R. 2124, October 2, 2015)) to de-couple the permitting thresholds from the definition of
“insignificant activity”. The department proposed to retain the original definition of “insignificant activity” as written in
Rule 100, Section 200.58 (new Section 200.63) with the deletion of “and that is either included in Appendix D-List of
Insignificant Activities of these rules”. In addition, in Rule 200, Section 305.4 (Exemptions), the department proposed to
delete (as an exemption from needing to obtain a permit) the text “Insignificant activities, provided any single or
combination of insignificant activities have total uncontrolled emissions less than the permitting thresholds as defined in
Rule 100 of these rules”. In addition, the department proposed to simply list the activities, processes, or emissions units
that match those listed in the definition of “insignificant activity”.
Realizing the department inadvertently deleted a restriction on the quantity of emissions that may be exempted from
permit, the department is proposing to restore an emissions limit (two tons per year of a regulated air pollutant) above
which any single or combination of activities is required to obtain a permit (in Rule 200, Section 305). As ADEQ’s rules
contained a restriction on the number of categorically exempt activities, the text in Rule 200, Section 305 is substantially
identical to the sense, meaning, and effect of ADEQ’s NSR rules R18-2-302(C)(1).
 Rule 200, Section 305 (Exemptions): In response to SRP’s comments submitted on November 9, 2015, to change the first
sentence to specifically designate the activities listed in Sections 305.1 through 305.10 as being exempt from obtaining a
permit. Added a second sentence describing emission limits for any single or combination of activities above which a
permit is required
 Rule 200, Section 305.2 (Exemptions): In response to SRP’s comments submitted on November 9, 2015, to move proposed
new Section 305.2 to Section 303.2(a) (Non-Title V Permit)
 Rule 200, Section 305.3 (Exemptions): In response to SRP’s comments submitted on November 9, 2015, to move proposed
new Section 305.3 to Section 303.2(b) (Non-Title V Permit)
 Rule 200, Section 310.1 (Permit Conditions): To change reference from “Section 310.3 of these rules” to “Section 310.5 of
these rules”
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 Rule 200, Section 310.4 (Permit Conditions): To delete “or a permit renewal application” and to add “permit” in the phrase
“or for permit denial” in the second to-the-last sentence in the section. Permit non-compliance is not grounds for a permit
renewal application
 Rule 200, Section 401.1 (Approval Or Denial Of Permit Or Permit Revision): To add “or applicable State Implementation
Plan (SIP) plan requirements” to the end of the sentence
 Rule 210, Sections 301.8(f) and (h) (Action On Application): In response to SRP’s comments submitted on November 9,
2015, to remove the propsed deletion of these sections. The department proposes to retain the original text of Rule 210,
Sections 301.8(f) and (h)
 Rule 220, Section 301.3(c) (Permit Application Processing Procedures-A Timely Permit Application): To add “If such
standard requires the source to obtain a Title V permit, then the” to the beginning of the first sentence
 Rule 220, Section 301.6(b)(4) (Permit Application Processing Procedures-Action On Application): To change “an
application” to “a proposed permit” in the first sentence; a permit application is not required to be submitted to the EPA
 Rule 220, Section 405.3(c) (Permit Revisions-Non-Minor Permit Revisions): To delete “not” from the proposed phrase “A
change that is not a minor NSR modification…”. Section 405.3(c) is proposed to read “A change that is a minor NSR
modification for which public participation is required under Rule 241 of these rules”. Rule 220, Section 405.2(a)(1)
(Permit Revisions-Minor Permit Revisions) is not proposed to be changed; it is proposed to read “The change is not a
minor NSR modification for which public participation is required under Rule 241 of these rules”
 Rule 230, Section 306.3 (General Permit Renewal): In response to SRP’s comments submitted on November 9, 2015, to
delete the proposed sentences “Until such time that a timely application is submitted, the source shall continue to comply
with the previously issued general permit coverage. Upon submittal of a timely application, the source shall comply with
the renewed permit” and to add “If a source submits a timely and complete application for a permit renewal, but the
Control Officer has failed to issue or deny the renewal permit before the end of the term of the previous permit, then the
permit shall not expire until the permit renewal has been issued or denied”
 Rule 240, Section 301 (Perimt Or Permit Revision Required): To change “shall meet those requirements” to “shall meet the
requirements of this rule” at the end of the sentence
 Rule 240, Section 302.5 (Application Completeness): To add “to satisfy BACT or LAER, as applicable” to the end of the
first sentence
 Rule 240, Section 303.2(d)(1) (Application On Application And Notification Requirements): To delete “The Control
Officer for the county wherein the proposed or existing source that is the subject of the permit or permit revision
application is located”. Since the department is a county agency, the department does not need to send a notice requesting
public hearing to itself
 Rule 240, Section 303.5(d) (Application On Application And Notification Requirements): To add “That the new or
modified source has met the BACT or LAER control technology requirements as applicable in Sections 304 and 305 of this
rule” to ensure that Control Officer determines that the control technology requirements are met prior to issuance of a
preliminary decision to issue a permit or permit revision
 Rule 240, Section 304 (Permit Requirements For New Major Sources Or Major Modifications Located In Nonattainment
Areas): To change introductory text so it is consistent with introductory text in Rule 240, Section 305
 Rule 240, Section 304.3 (Permit Requirements For New Major Sources Or Major Modifications Located In Nonattainment
Areas-Emission Offsets): To change “source or modification is classified as major” to “proposed project will result in a
new major stationary source or a major modification” at the end of the first sentence and to add “offset” before “ratio” in
the second sentence
 Rule 240, Section 304.13 (Permit Requirements For New Major Sources Or Major Modifications Located In
Nonattainment Areas): To change text to be consistent with EPA’s intent that such sources not even be major sources and
to be consistent with ADEQ’s NSR rules R18-2-403(E)
 Rule 240, Section 305.1(d)(1) (Permit Requirements For New Major Sources Or Major Modifications Located In
Nonattainment Areas): In response to SRP’s comments submitted on November 9, 2015, to remove (i) from the list of
cited 40 CFR 52.21 paragraphs
 Rule 240, Section 305.2 (Permit Requirements For New Major Sources Or Major Modifications Located In Nonattainment
Areas): Per EPA directive, to delete “additional” from the section heading
 Rule 240, Section 305.2(a) (Permit Requirements For New Major Sources Or Major Modifications Located In
Nonattainment Areas): Per EPA directive, to change “an increase in ambient concentrations” to “a violation of a NAAQS”
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 Rule 240, Section 305.2(b) (Permit Requirements For New Major Sources Or Major Modifications Located In
Nonattainment Areas): Per EPA directive, to change the reference from “51.165(a)(11)(b)(2)” to “51.165(b)(2)”
 Rule 240, Section 305.2(c) (Permit Requirements For New Major Sources Or Major Modifications Located In
Nonattainment Areas): Per EPA directive, to delete “to a major source” after “major modification” in the first sentence
 Rule 240, Section 305.2(d) (Permit Requirements For New Major Sources Or Major Modifications Located In
Nonattainment Areas): In response to SRP’s comments submitted on November 9, 2015, to delete “as” from the phrase
“designated nonattainment areas”
 Rule 240, Section 305.2(e) (Permit Requirements For New Major Sources Or Major Modifications Located In
Nonattainment Areas): Per EPA directive, to delete “required” after “the demonstration” in the first sentence
 Rule 240, Section 306.3(b) (Stack Height Dispersion Techniques): To delete “Coal fired steam electric generating units,
subject to the provisions of Section 118 of the Clean Air Act which commenced operation before July 1, 1957, and whose
stacks constructed under a construction contract awarded before February 8, 1974”. Maricopa County does not have any
such sources
 Rule 241, Section 102 (Applicability): In response to SRP’s comments submitted on November 9, 2015, to clarify the
types of construction and minor NSR modification that are regulated by Rule 241; to include the language in Sections
102.1 and 102.2 in the opening paragraph of Section 102 and to add the word “when” to introduce Sections 102.3 and
102.4 (and to re-number Sections 102.3 and 102.4 to 102.1 and 102.2); in the previously numbered Section 102.4 (now
numbered Section 102.2), to change the phrase “potential to emit” to “maximum capacity to emit”
 Rule 241, Section 102.2 (Applicability): To change “source’s potential to emit” to “source’s maximum capacity to emit”
 Rule 241, Section 304.2 (BACT Required): To change “increase in emissions” to “increase in the source’s maximum
capacity to emit”
 Rule 241, Section 306.4 (BACT Determinations): In response to SRP’s comments submitted on November 9, 2015, to
change the phrase “the control of each emission point for the subject pollutant at a facility or the affected area” to “the
source or group of sources being modified”
 Rule 241, Section 308 (NAAQS Compliance Assessment): To change “a standard imposed in” to “any national ambient air
quality standard” at the end of the sentence
 Rule 241, Section 308.1 (NAAQS Compliance Assessment): To change “a standard imposed in” to “any national ambient
air quality standard”
 Rule 241, Section 308.2(a) (NAAQS Compliance Assessment): To change “the violation of a standard imposed in” to “a
violation of any national ambient air quality standard”
 Rule 241, Section 309.1 (Application Denial): To change “a standard imposed in” to “of any national ambient air quality
standard”
 Rule 241, Section 310 (Public Notice): To change “each” to “any one” in the phrase in the first sentence “…if the
emissions for any one pollutant are equal to or greater than…”
13. Summary of the comments made regarding the rules and the department response to them:
After the Notice of Proposed Rulemaking was published on July 31, 2015 (21 A.A.R. 1302), the Salt River Project
Agricultural Improvement and Power District (SRP) submitted comments on August 31, 2015. The comments and the
department’s responses are included in the Draft Notice of Final Rulemaking that was submitted to the Board of Supervisors
on October 9, 2015 and posted on the Enhanced Regulatory Outreach Program (EROP) website on November 3, 2015.
A Notice of Supplemental Proposed Rulemaking was published in the Arizona Administrative Register (A.A.R.) on October
2, 2015 (21 A.A.R. 2124). The notice included rule amendments based on SRP’s comments submitted on August 31, 2015.
After the Notice of Supplemental Proposed Rulemaking was published on October 2, 2015 (21 A.A.R. 2124), SRP submitted
comments to the department on November 9, 2015 (the last day of the 30-day comment period). A Notice of Supplemental
Proposed Rulemaking is scheduled to be published in the Arizona Administrative Register on December 18, 2015. The notice
will include rule amendments based on SRP’s comments submitted on November 9, 2015.
SRP’s comments submitted on November 9, 2015 addressed the following categories:
 Definitions: The department is proposing to revise seven definitions mainly to provide clarity and eliminate potential
conflict with ADEQ NSR rules.
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 Permitting thresholds: The department is proposing to increase the minor NSR modification thresholds to match ADEQ;
this will allow sources within Maricopa County that are below the thresholds to avoid triggering NSR requirements
(modeling and permit revisions). The department is also proposing to clarify which activities are exempt from obtaining a
permit (insignificant activities). This change may actually reduce not increase the number of permits issued by the
department.
 Permitting process: The department is proposing to retain the licensing time frames that define action on permit
applications, to provide an application shield to general permit applicants, and to follow EPA guidance when granting
construction extensions. These revisions provide sources certainty that the department will take timely action on their
permit applications.
 Minor NSR program: The department is proposing to clarify the types of facility modifications that are regulated by Rule
241 (Minor New Source Review (NSR)) and to retain the language in Rule 241 that requires best available control
technology (BACT) to address emissions from the sources being modified. These clarifications will assist sources in
determining if a permit revision is required.
SRP’s comments submitted on November 9, 2015 and the department’s responses are provided below.
Comment #1 NSPRM: ADEQ’s Minor NSR Thresholds are Appropriate for Many Source Categories and Criteria Pollutants
in Maricopa County
On July 6, 2012, the Arizona Department of Environmental Quality (ADEQ) adopted changes to its permitting regulations
that implement major and minor NSR. These changes included adopting minor NSR thresholds between 0.3 and 50 tons per
year (tpy) for criteria pollutants. Under this proposal, MCAQD structured its proposed minor NSR rule to apply to all
stationary source categories that would emit above the proposed applicability thresholds whether the stationary source is
located in an attainment area or nonattainment area for that pollutant. However, MCAQD’s proposed applicability thresholds
are lower than the thresholds adopted by ADEQ in its recent NSR rule revisions. When compared to ADEQ’s rules, these
lower thresholds result in not only a more stringent minor NSR program, but they also increase the stringency of the Title V
permit revision procedures by defining more changes as significant modifications. Under Arizona Revised Statutes (A.R.S.)
§49-112, MCAQD may not adopt regulations that are more stringent than ADEQ’s rules unless MCAQD provides technical
and economic analyses to justify adopting more stringent standards than ADEQ’s. MCAQD’s public notice contains no
technical information to support its assertion that a more stringent minor NSR program is necessary for Maricopa County to
achieve attainment. MCAQD’s justification contains no analysis comparing its proposed thresholds with the levels adopted
by ADEQ to explain the difference in the amount of emissions and cost that results from applying one program versus the
other, or how applying ADEQ’s thresholds would prevent ADEQ from achieving or maintaining compliance with each
National Ambient Air Quality Standard (NAAQS). This analysis is necessary both to justify MCAQD’s assertion that it
requires a more stringent NSR program and to justify MCAQD’s minor NSR modification and public participation thresholds
for inclusion in the state implementation plan (SIP). It is critical for continued economic development and the sustainability
of existing industry in Maricopa County that MCAQD establish minor NSR applicability thresholds that are technically-
based and appropriate for the air quality needs of the County. In this regard, SRP suggests that MCAQD proceed cautiously,
in a stepwise approach, in regulation of minor NSR under the SIP. If MCAQD adopts ADEQ’s applicability thresholds and
then determines that additional regulation is required, MCAQD can strengthen the regulations through an additional
regulatory action. A reverse scenario is not easily corrected. If EPA approves the changes into the SIP, and then MCAQD
determines that its regulations are overly stringent, the anti-backsliding provisions in the Clean Air Act (CAA) prohibit EPA
from revising the regulations applicable in some nonattainment areas, and requires extensive technical analysis to justify a
revision in other areas. Accordingly, SRP cannot overstate the importance of establishing the correct thresholds in the first
instance before adding the requirements to the SIP. Across-the board regulations that are more stringent than ADEQ’s are
unwarranted. MCAQD should consider a more tailored approach that evaluates each pollutant and the types of stationary
sources it should regulate to achieve or maintain NAAQS compliance. MCAQD should also expand the costs benefits
analysis so that it contains a full economic analysis, including the cost of emissions controls consistent with the requirement
under A.R.S § 49-112. Ultimately, when MCAQD conducts the required analysis to determine which sources it should
regulate under its minor NSR program to achieve the NAAQS, it likely will find that the levels adopted by ADEQ for its
statewide NSR program are appropriate for many source categories in Maricopa County, and for all attainment or
unclassifiable areas.
Response #1 NSPRM: ADEQ’s Minor NSR Thresholds are Appropriate for Many Source Categories and Criteria Pollutants
in Maricopa County
SRP questions why the county’s permit exemption threshold and minor NSR modification threshold need to be more
stringent than ADEQ’s permit exemption threshold. The comment further states that MCAQD’s public notice did not contain
sufficient technical justification support the county’s existing program as necessary for achieving and maintaining attainment
or to demonstrate that the county’s program needs to be more stringent than the state’s permit program under A.R.S. § 49-
112.
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Maricopa County’s Proposed NSR Thresholds: As explained in the preamble, Maricopa County has been designated as
nonattainment for ozone, particulates and carbon monoxide. Further, the county monitoring network has recorded levels of
the annual standard PM2.5 standard just under the national standard at several monitoring sites. In addition, Maricopa County
has received a clean data determination for PM10 and has been re-designated to attainment subject to a maintenance plan for
two older ozone standards and the carbon monoxide standard. Under a maintenance plan, the region must continue to
implement all the control measures that brought the area into attainment. The state implementation plan for Maricopa County
for all pollutants contains an extensive number of control measures from prior SIP submittals and nonattainment area plans
that apply at thresholds significantly below ADEQ’s permit exemption thresholds. Both the ozone portion of the SIP (as
directed by A.R.S. 11-873) and the PM10 portion of the SIP also contain a number of control measures designed to improve
rule effectiveness. Further, unlike ADEQ, Maricopa County’s nonattainment problems aren’t attributed to a single very large
source. The county’s large metropolitan area contains over half of the state’s population and has a very different profile of
sources types and sizes than the rest of the state. Specifically, Maricopa County’s nonattainment challenges arise from the
large number of small sources (called area sources), on-road mobile sources and non-road mobile sources.
EPA’s minor source regulations require a permitting authority to make two determinations before issuing a permit. This
comment has focused on the second required determination while overlooking the first required determination. In the Code
of Federal Regulations, EPA has established requirements that apply to minor NSR programs in 40 CFR § 51.160 through
51.164. Specifically, 40 CFR § 51.160(a) states, “Each plan must set forth legally enforceable procedures that enable the
State or local agency to determine whether the construction or modification of a facility, building, structure or installation, or
combination of these will result in—(1) A violation of applicable portions of the control strategy; or (2) Interference with
attainment or maintenance of a national standard in the State in which the proposed source (or modification) is located or in a
neighboring State.” The county's minor source permit program has historically been utilized as the compliance and
enforcement mechanism to prevent violations of the applicable portions of control strategy and preconstruction review is a
critical element of that program. Maricopa County Air Pollution Control Regulation III contains numerous source-specific
rules that implement the control technology and control measures submitted and approved into the State Implementation Plan
(SIP). These rules include applicability criteria significantly below ADEQ’s permit exemption threshold ranging from
equipment sizes to size of disturbed surface area to emission thresholds of 15 pounds per day (2 tons per year) for example.
The proposed rules include two distinct thresholds for the minor NSR program. The permit exemption threshold establishes
when a permit is required, while the minor NSR modification threshold establishes when an existing source initiating a
modification will trigger the requirement of Rule 241 (Minor New Source Review). The permit exemption threshold is a key
mechanism for ensuring that facilities and activities do not violate applicable portions of the control strategy and no change
has been made. However, there is some flexibility in establishing the minor NSR modification threshold that applies once a
source obtains a permit. As noted in the preamble, the department has reviewed past permit modification actions and
estimates approximately 5% of all applications may need to perform an air quality assessment to determine if the applicant
could interfere with attainment or maintenance of the NAAQS. As a result, the department has reconsidered, conducted a
further review of permit modeling results, and now believes that ADEQ’s thresholds should be sufficient to assure changes
and modifications that may need to conduct a source specific air quality assessment are processed under the Rule 241. In the
event an unforeseen modification is proposed, the department has general authority to request an air quality impact
assessment under Rule 200, Section 310 or may simply conduct the assessment during the permit review process. The
department has revised the proposed minor NSR modification thresholds to match ADEQ’s permit exemption threshold and
will update the economic analysis to reflect the revised estimates for modeling.
As for ensuring that changes below the minor NSR modification thresholds will not violate the control strategy, existing
sources holding permits are subject to Rules 210 and 220, as well as, the proposed provision in Rule 241, Section 313 which
requires any modifications to NSR permit conditions to be modified under to Rule 241 or 240. These rule provisions will be
sufficient to prevent violations of the control strategy. Those rules contain specific criteria for various levels of permit
revision (e.g. minor, significant) that apply regardless of whether the minor NSR modification threshold applicability in Rule
241 is triggered. In addition, Rule 200, Sections 401.1 and 401.2 contain additional administrative requirements for approval
or denial of permit or permit revisions. Specifically, Rule 200, Section 401.2 requires the Control Officer to deny a permit or
revision if the applicant does not demonstrate that every such source for which a permit or permit revision is sought is so
designed, controlled, or equipped with such air pollution control equipment that the source may be expected to operate
without emitting or without causing to be emitted air contaminants in violation of the provisions of these rules. Under Rule
200, Section 401.2, the Control Officer may require the applicant to provide and maintain such devices and procedures as are
necessary for sampling and for testing purposes in order to secure information that will disclose the nature, extent, quantity,
or degree of air contaminants discharged into the atmosphere from the source described in the application. In the event of
such a requirement, the Control Officer shall notify the applicant in writing of the type and characteristics of such devices and
procedures.
SRP also raised concern with the Clean Air Act (CAA) anti-backsliding provisions and stated the county should propose to
match ADEQ’s permit exemption thresholds and then lower them if disapproved. However, Maricopa County’s minor NSR
program has a long history and has already been approved into Arizona’s applicable State Implementation Plan for Maricopa
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County beginning in May 1972 with thresholds significantly lower than the ADEQ permit exemption thresholds. As a result
the anti-backsliding provisions in the CAA that prohibit EPA from revising the regulations applicable in nonattainment areas,
and requires extensive technical analysis to justify a revision in other areas, already applies to Maricopa County’s NSR
rulemaking. (See CAA Sections 110(l) and 172(e), 42 U.S.C. §7410 and §7502.)
Technical Demonstration: The department has conducted technical demonstrations for the permit exemption threshold and
the public notice thresholds. While the full study and spreadsheets were not repeated in the preamble, the studies were
mentioned and a summary of their results included in the discussions on the permit exemptions thresholds and the public
notice thresholds. SRP did not ask to review the county’s studies and instead included its technical demonstration. However,
that demonstration relied upon only a partial list of sources under permit in Maricopa County and, as a result, does not
accurately portray the inventory in the county. While it is true that on-road mobile, non-road mobile and biogenic (naturally-
occurring) sources contribute significantly to the region’s nonattainment problems, the point (major) and area (minor) source
contributions are large enough to also be significant in nonattainment area plans. In addition, stationary source were
determined to be a significant contributor (of greater than 5 µg/m3 of PM10) to PM10 exceedances that occurred during
stagnant conditions in the 2004 Salt River SIP Revision. Further, the projections for the emission inventory contained in the
approved maintenance plans for ozone indicate that the contribution from point and area sources will increase in 2025 as the
contributions from both types of mobile sources decrease as a result of fleet turnover and federal clean fuel requirements
become effective. The department has added more descriptive text to the preamble text for the second supplemental notice of
proposed rulemaking.
A.R.S. § 49-112 Demonstration: SRP questions the county’s A.R.S. § 49-112 demonstration. Specifically, SRP does not
believe a more stringent permit threshold is required by federal law or by Maricopa County’s peculiar local conditions under
A.R.S. § 49-112.A and further discusses the costs analysis required by A.R.S. § 49-112.B for programs in lieu of a state
program. As described in the first response above, the rules and control measures addressing the specific source contributions
and profiles contained in the Maricopa County portion of the SIP do necessitate a lower permitting threshold than ADEQ to
prevent violation of the control strategies contained in various nonattainment plans. Second, the Maricopa County air quality
permit program is authorized under its original jurisdiction contained in A.R.S. Title 49, Chapter 3, Article 3 and is not
implemented in lieu of a state program. The department has conducted process improvements that include external
stakeholders to streamline the permit review process and endeavors to operate a timely, cost-effective permit program within
the constraints of the applicable SIP.
Comment #2 NSPRM: MCAQD Should Retain Authority to Implement the Existing SIP-Approved Program Until EPA Fully
Approves MCAQD’s SIP Submittal
The Arizona SIP currently contains a fully-approved NSR program applicable in Maricopa County. EPA has not formally
instituted a SIP call for that portion of the State Plan. This was also true for ADEQ’s NSR rules that applied in other parts of
the State. Yet, in acting on ADEQ’s NSR SIP submission, EPA asserted its authority to disapprove the submittal using a
limited approval/limited disapproval mechanism. This mechanism triggers SIP sanctions and an obligation for EPA to impose
a federal implementation plan (FIP) if the State does not correct the alleged deficiencies in the specified time period. In
responding to SRP’s comments questioning EPA’s legal authority to replace a fully approved SIP using a mechanism that
triggers SIP sanctions and a FIP, EPA responded that ADEQ had not opted to retain the current SIP-approved program. In
light of EPA’s response, and to avoid the potential for EPA to act on MCAQD’s NSR SIP submission in a similar manner,
MCAQD should include a provision in its final rules that retains authority for MCAQD to implement the current version of
the approved SIP for any source, or any part of its jurisdiction, for which EPA fails to approve the SIP submission. As long as
MCAQD still has State authority to implement the approved SIP, EPA should not have legal authority to impose SIP
sanctions or a FIP without first undertaking a SIP call. Such an approach for processing the SIP submittal would avoid the
unfortunate consequence of removing a fully approved program from the SIP and replacing it with one which contains any
aspect that EPA believes would trigger SIP sanctions and a FIP if not corrected.
Response #2 NSPRM: MCAQD Should Retain Authority to Implement the Existing SIP-Approved Program Until EPA Fully
Approves MCAQD’s SIP Submittal
The EPA last approved revisions to the Maricopa County NSR SIP in 1988. See 53 Fed. Reg. 30220 (Aug. 10, 1988). Since
the amendments last approved by EPA were adopted, the county has re-organized forming the Maricopa County Air Quality
Department and has made substantial revisions to the program. Most significantly, in 1992 through 1993, the Arizona State
adopted legislation, followed by conforming rule amendments, to move from the old installation and operating permit
program to a “unitary” program that authorizes both construction and operation in a single permit. NSR requirements for new
sources are now enforced as part of the issuance of a single permit that also ensures compliance with all other applicable
requirements of state and federal air quality laws. For major sources, these permits are designed to comply with title V of the
Act, as well as Parts C and D of title I. Major modifications subject to major NSR now require a significant revision to the
permit for an existing source, rather than a new installation permit. Other modifications that formerly required an installation
permit may now proceed under either a significant or minor permit revision. In addition to adopting the unitary permit
program, Maricopa County also has updated its NSR rules to incorporate, e.g., the PM10 and PM2.5 NAAQS, the PM10
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increments, and the “WEPCO” rule redefining the method for determining whether a modification to an electric generating
unit is major. None of these changes are included in the approved NSR SIP for Maricopa County. Under federal law,
Maricopa County remains obligated to continue enforcing the old NSR program until EPA approves the new one.
Fortunately, the new program is in most cases more stringent than the old, so that compliance with current rules is largely
sufficient to assure compliance with the approved NSR SIP. There are a few instances, however, in which the old rules
require review procedures that go beyond the current program. Maricopa County has had to issue guidance explaining that in
these cases the department will apply the approved SIP, rather than the current rules. It would obviously be preferable for the
requirements of the SIP and the current rules to match. Maricopa County is, therefore, seeking through these rule
amendments to eliminate the SIP gap for the permit program.
Comment #3 NSPRM: MCAQD Must Clarify that it Does Not Intend to Regulate Ammonia Emissions as a Precursor to
PM2.5 in Any of MCAQD’s Permitting Programs
Under Rule 100, Section 200.107, MCAQD proposes to include ammonia, as a precursor to particulate matter nominally less
than 2.5 microns (PM2.5), in the definition of a “regulated NSR pollutant” in nonattainment areas. Under Rule 240, MCAQD
proposes to incorporate by reference the definitions in the Federal Prevention of Significant Deterioration (PSD) regulations
at 40 CFR §52.21(b) and §51.165(a)(1) and states that, to the extent there are conflicts in the definitions of this rule and
MCAQD’s rules, the definition in this rule applies. This suggests that MCAQD intends for the Federal definitions to apply
for purposes of major NSR in lieu of the definition in Rule 100. However, the preamble states, “under NRDC decision… and
EPA proposal, ammonia must be treated as a precursor for PM2.5”. The preamble then explains that the definition of
regulated NSR pollutant is revised so that ammonia is not a regulated NSR pollutant for PSD. This leaves the reader with the
implication that ammonia is a regulated NSR pollutant for nonattainment areas, and generally calls into question how the
definitions in Rule 100 interact with the definitions incorporated by reference in Rule 240, since the Rule 100 definitions
seem to address many major NSR concepts. Moreover, even if the Federal definitions apply for purposes of major NSR,
defining ammonia as a regulated NSR pollutant has permitting implications elsewhere in the rule. For example, Rule 200,
Section 303.1 requires non-Title V permits for certain changes that increase emissions of a regulated NSR pollutant. It
appears that ammonia would be a “regulated NSR pollutant” in this context, but there is no threshold defined. This raises the
question as to whether ammonia is regulated, but has a threshold of zero, or whether it is not regulated under that provision.
MCAQD proposes to regulate ammonia as a precursor to PM2.5 in nonattainment areas before EPA or ADEQ have
determined that such treatment of ammonia is appropriate. Until both EPA and ADEQ finalize their position on treating
ammonia as a precursor, it is inappropriate for MCAQD to define ammonia as a precursor in nonattainment areas for any
purpose without justifying the action under A.R.S. § 49-112. MCAQD’s current administrative record lacks such a showing.
If MCAQD includes ammonia as a PM2.5 precursor, it must concurrently establish a significant emissions rate; otherwise the
current regulations would require “any” increase in ammonia to go through permitting.
Response #3 NSPRM: MCAQD Must Clarify that it Does Not Intend to Regulate Ammonia Emissions as a Precursor to
PM2.5 in Any of MCAQD’s Permitting Programs
SRP is correct in that there is a conflict regarding how “regulated NSR pollutant” is proposed to be defined in Rule 100 and
how it is proposed to be defined in Rule 240. Consequently, the department is proposing to change the definition of
“regulated NSR pollutant” in Rule 100, Section 200.106 to reference the reader to Rule 240 (Federal Major New Source
Review (NSR)); “regulated NSR pollutant” is defined in Rule 240 and is covered under the definition of “regulated minor
NSR pollutant” (defined in Rule 100, Section 200.105).
Comment #4 NSPRM: MCAQD Must Provide a Technical Justification for the Public Participation Threshold
Under the CAA and EPA’s implementing regulations at 40 CFR § 51.160(e), a reviewing authority may define the type and
size of stationary source it will regulate under its minor NSR program. A reviewing authority should determine the scope of
its minor NSR program based on whether it is necessary to regulate such sources “to assure that national ambient air quality
standards are achieved”. Once a reviewing authority defines this scope, EPA policy requires all of these identified stationary
sources to meet the minimum minor NSR program requirements in 40 CFR §51.160-164, including public review. EPA’s
most extensive discussion of this relationship between 40 CFR §51.160(e) and public review requirements is contained in a
supplemental proposal for Title V permit programs: ”Application of public participation procedures to new and modified
sources under minor NSR programs must be consistent with the statutory and regulatory purposes of those programs, and
EPA believes that tailoring this application to the environmental significance of new or modified sources on a categorical or
individual basis is consistent with these purposes.” Although EPA presented this interpretation in a proposed rule that it never
finalized, Regional Offices based approval of tailored public participation requirements in other State minor NSR programs
on this interpretation. To be clear, EPA’s interpretation does not provide that a State show that public participation has no
environmental significance, but that the modification falls below thresholds that would require full regulation under the
State’s minor NSR program. Accordingly, once MCAQD concludes that a source must be regulated under its minor NSR
program, it has no authority to exclude that source from any part of the substantive program requirements, including public
participation. Under MCAQD’s proposed permitting thresholds, EPA’s policy would require MCAQD to subject all the
permit applications it expects to receive each year to public notice. For a new source, this could mean a source emitting as
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little as 0.5 tpy VOC could not receive a permit until a proposed permit undergoes public review. Moreover, MCAQD’s
current cost assessment contains assumptions that seemingly support public participation requirements for all permits, in that
MCAQD estimated that it will require 95% of applicants to conduct SCREEN modeling and 5% of applicants to conduct
refined modeling. A Control Officer may request modeling only if there is a reason to believe that a source may interfere with
attainment or maintenance of the NAAQS. By projecting that MCAQD will require 100% of minor NSR permit applicants to
conduct modeling, MCAQD undermines a contention that public review is not necessary for some of these applications.
Importantly, however, MCAQD’s cost analysis makes no attempt to first determine whether emissions from these applicants
need to be regulated under the County’s minor NSR program to achieve attainment. To prevent unwarranted delays in
processing permit applications for de minimis emissions increases (i.e., those with little to no possibility of preventing the
County from achieving attainment), MCAQD must undertake a quantitative or qualitative analysis to identify which sources
MCAQD needs to regulate through its minor NSR program (if any) to achieve attainment. MCAQD may determine that it is
not necessary to regulate certain types of sources because existing MCAQD regulations already assure that such sources will
not cause or contribute to a NAAQS violation. In a recent Advanced Notice of Proposed Rulemaking, EPA requested
comment on promulgating a regulation for minor sources in the oil and gas industry in lieu of regulating such sources under
the Federal minor NSR Indian Country preconstruction permit rule. Similarly, MCAQD already promulgated numerous
control technology regulations for certain source categories. These control requirements reduce the likelihood that these
sources could cause or contribute to a NAAQS violation, and the public already had an opportunity to comment on the rule.
Therefore, exempting such sources from additional public participation requirements is appropriate. Once MCAQD identifies
the sources that are necessary to include in the minor NSR program, EPA will allow MCAQD to regulate additional
stationary sources under its SIP for other reasons. For example, ADEQ’s Registration Program provides a “back stop” by
screening exempt sources to assure accountability in the source’s emissions estimates, and to confirm the non-applicability of
minor NSR. Indiana, Texas, and New Mexico adopted similar tiered regulatory structures for sources undertaking changes
that increase emissions below the significant emissions rates based on a finding that full regulation of some categories or size
of sources is not necessary for attainment. Similarly, notwithstanding a finding that certain source categories will not cause or
contribute to a NAAQS violation, MCAQD could still require preconstruction permits for these smaller area sources to
improve rule effectiveness. In sum, with the proper technical showing, MCAQD could adopt ADEQ’s minor NSR
applicability thresholds generally, but regulate particular categories of smaller area sources at a lower applicability level to
enhance enforcement and the effectiveness of its existing SIP control measures without requiring these permits to undergo
public review. If MCAQD does not justify the public participation thresholds before submitting SIP revisions to EPA, and
EPA disapproves this aspect of the submittal, then the permitting and minor NSR modification threshold may become the
default threshold for public participation. Therefore, MCAQD must provide a technical justification for the public
participation threshold.
Response #4 NSPRM: MCAQD Must Provide a Technical Justification for the Public Participation Threshold
Maricopa County has worked with EPA Region IX on the requirements for public notice and the type of demonstration that
should accompany the NSR rulemaking. The department further reviewed the federal register notices in which EPA approved
other agencies minor NSR programs in regard to their permitting thresholds, public notice thresholds and technical
demonstrations. For example, EPA has approved minor source programs in Bay Area Air Quality Management District,
Ventura County, Sacramento County in California as well the Clark County program in Nevada that include public notice
thresholds higher than the permitting thresholds. Based on these approved programs notices, the department has determined
that EPA will approve a public participation threshold that is higher than the permitting threshold with appropriate
documentation. The department prepared its demonstration study following examples from these other agencies that were
suggested by EPA.
The preamble to this notice notes the department conducted a study and summarized the results of the study as justification
for the permitting threshold and the public notice threshold proposed. SRP did not ask to review the county’s studies and
instead included its own demonstration. However, that demonstration relied upon only a partial list of sources under permit in
Maricopa County and, as a result, does not portray the complete inventory for the county. Based on the department’s study of
permits and past permitting actions, MCAQD projects that approximately 3,085 Non-Title V permits, including General
permits, out of 4,221 total Non-Title V permits or 73.1% of Non-Title V permits will undergo a 30-day public notice. The
remaining Non-Title V permits are smaller sources and are subject to RACT or BACT rules that have gone through the
public notice and comment process at the time of adoption. The remaining Non-Title V permits will have the receipt of their
applications notice online and the issuance of their permit noticed in the department’s monthly publication of issued permits.
The department has added additional text to the preamble text for the second supplemental notice of proposed rulemaking.
SRP suggests a tiered permitting scheme implemented by ADEQ that added a registration program that includes a “back
stop” by screening exempt sources to assure accountability in the source’s emission estimates and confirm nonapplicability of
minor NSR. ADEQ did add a registration program for smaller sources, however, that registration program still includes
public notice for many of the registrations. ADEQ notes this change was necessary to address an EPA identified deficiency
that ADEQ’s permitting thresholds were inadequate to attain and maintain the federal standards. Maricopa County was not
subject to such a finding and does not find it necessary to lower its permitting thresholds. The proposed revisions have
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retained the current permit program structure but converted both the permitting thresholds and the public notice thresholds to
a ton per year form. Maricopa County’s public notice thresholds are already higher than the permitting thresholds so many
smaller sources currently do not undergo a 30-day public notice. Since the county can justify retaining the higher public
notice thresholds supported by the documentation prepared, the department has determined it is not necessary to develop a
new registration program for smaller sources.
In addition, the department also makes extensive use of the general permit program provided in the existing rules that
provides an even more streamlined permitting process than a registration program. Under the general permit program, the
master general permit is prepared consistent with all minor NSR requirements and all unitary permit requirements. The
master permit undergoes public notice, and once issued, each individual permit authorization or permit revision authorization
can be issued within 2 to 3 days. The county then publishes a list all permits issued, including general permit authorizations,
once a month. The department has currently issued 2,890 general permit authorizations out of a total of 4,221 Non-Title V
stationary source permits.
Comment #5 NSPRM: MCAQD Should Adjust the Contemporaneous Period to Promote Regulatory Certainty
MCAQD proposes to include language that mirrors the contemporaneous timeframe in ADEQ and EPA rules. Defining the
period in this manner requires MCAQD and the source to project a future construction date when processing permit
applications. EPA has raised concerns, after a reviewing authority issued a final permit, when the projected construction date
differs from the actual construction date in a way that affects the netting analysis. To avoid the regulatory uncertainty that
occurs from a moving contemporaneous period, MCAQD should change the contemporaneous period regulations to read:
“between the date five (5) years before submitting a permit application or commencing construction of the particular major
modification, whichever is sooner, and the date that the increase from the particular major modification occurs…”. This
definition is neither more stringent nor less stringent than ADEQ’s and EPA’s definition because it is as likely to require the
continued consideration of emissions increases as decreases over the potentially extended contemporaneous period. The
change merely provides certainty and clarity for implementation.
Response #5 NSPRM: MCAQD Should Adjust the Contemporaneous Period to Promote Regulatory Certainty
In Rule 240, the department is proposing to incorporate by reference 40 CFR 51.155(a)(1), which includes the definition of
“net emissions increase”. In the incorporated definition of “net emissions increase”, the department is proposing to replace
“reasonable period” with “between the date five years before construction on the date the particular change commences, and
the date that the increase from the particular change occurs.” This change is consistent with ADEQ’s NSR rules R18-2-
101(88) (Definition of “Net Emissions Increase”). However, in this notice (under Item 6, in third paragraph of “Revisions to
Maricopa County Major NSR Program”) the department is soliciting comments on two other options for defining “reasonable
period” in the definition of “net emissions increase”.
Comment #6 NSPRM: MCAQD Should Retain the Current Exclusion for Increases in Hours of Operation and Production
Rate Within the Definition of Major Modification
In Rule 100, Section 200.64, MCAQD proposes to remove paragraph (c)(6) from the definition of “major modification”,
which specifies that an increase in the hours of operation or in the production rate under specified circumstances is not a
major modification. MCAQD has not explained the basis for the change. ADEQ’s rules, Federal regulations, and MCAQD’s
current regulations exclude this activity from the definition of major modification.
Response #6 NSPRM: MCAQD Should Retain the Current Exclusion for Increases in Hours of Operation and Production
Rate Within the Definition of Major Modification
In Rule 100, Sections 200.64(c)(5) and (c)(6) (Definition of “Major Modification”), the department is proposing to change
the definition of “major modification” so it is consistent with ADEQ’s NSR rules R18-2-101(74). The text that specifies that
an increase in the hours of operation or in the production rate under specified circumstances is not a major modification is
proposed to be returned to the definition of “major modification”.
Comment #7 NSPRM: MCAQD Should Correct Conflicts Between MCAQD’s Prior Exemption List and MCAQD’s
Insignificant Activities List
In Rule 200, Section 305, the exemption list appears to conflict with MCAQD’s prior exemption list and insignificant
activities list. The exemption thresholds in Sections 305.2 and 305.3 appear to conflict with the thresholds in Sections 305.6
and 305.8. For example, an emergency internal combustion engine that emits at 4,000 pounds per year would be exempt
under Sections 305.8, but would not qualify for an exemption under Section 305.2 and 305.3 because it emits above the
permitting threshold. To address this issue, SRP recommends that MCAQD add the following language to Section 305: “A
source that qualifies for any one of the listed exemptions is exempt from obtaining a permit even if the source does not
qualify under all applicable exemptions for that source type.” Moreover, MCDAQD should reference the exemption section
in Rule 241 to make clear that these activities are not subject to minor NSR permitting. To address this issue, MCAQD
should amend the language in Rule 241, Section 103 to add the following language: “The provisions of this rule also do not
apply to any activity exempt from permitting under Rule 200, Section 305.”
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Response #7 NSPRM: MCAQD Should Correct Conflicts Between MCAQD’s Prior Exemption List and MCAQD’s
Insignificant Activities List
In Rule 200, Sections 303.2(a) and (b) (Non-Title V Permit), the department is proposing to add text from new Section 305.2
(Exemptions) and Section 305.3 (Exemptions) to clarify thresholds for exemptions from obtaining a permit and thresholds for
insignificant activities. In Rule 200, Section 305 (Exemptions), the department is proposing to change the first sentence to
specifically designate the activities listed in Sections 305.1 through 305.10 as being exempt from obtaining a permit and to
add a second sentence describing emission limits for any single or combination of activities above which a permit is required.
In Rule 200, Sections 305.2 (Exemptions), the department is proposing to move new Section 305.2 to Section 303.2(a) (Non-
Title V Permit). In Rule 200, Sections 305.3 (Exemptions), the department is proposing to move new Section 305.3 to
Section 303.2(b) (Non-Title V Permit).
Comment #8 NSPRM: MCAQD Should Amend the Regulatory Text of Various Sections of the Proposed Rule Revisions
Attachment B to this letter contains a list of the additional regulatory text changes that SRP recommends MCAQD implement
as part of this rulemaking process.
Response #8 NSPRM: MCAQD Should Amend the Regulatory Text of Various Sections of the Proposed Rule Revisions
The department considered SRP’s comments in Attachment B of their November 9, 2015 comments. See comments and
responses below.
SRP’s Attachment B Comment #1: Rule 100, Section 200.50 (Definition of “Existing Source”)
MCAQD should remove the definition of “existing source” from the definitions as it is confusing and unnecessary. As
written, all sources that would construct after the effective date of the rule would be “new” and not existing, even if that
source subsequently exists for many years after the effective date of the rules. The definition of existing source is not
necessary for the major NSR permit programs, because MCAQD already incorporated the Federal definition by reference.
For purposes of the minor New Source Review (NSR) programs, whether a source is “existing” should be in reference to the
date of a proposed change, not rule approval. ADEQ also eliminated this term from its definitions in its latest rule revisions.
SRP’s Attachment B NSPRM Response #1: Rule 100, Section 200.50 (Definition of “Existing Source”)
In Rule 100, Section 200.50 (Definition of “Existing Source”), the department is proposing to change the definition of
“existing source” to “any source that is not a new source” and in Rule 100, Section 200.76 (Definition of “New Source”), the
department is proposing to change the definition of “new source” to “a source for which construction has not commenced
before the effective date of an applicable rule or standard to which a source is subject”.
SRP’s Attachment B Comment #2: Rule 100, Section 200.71 (Definition of “Minor NSR Modification”)
MCAQD’s definition refers to “minor NSR thresholds” and should refer to “minor NSR modification thresholds”.
SRP’s Attachment B Response #2: Rule 100, Section 200.71 (Definition of “Minor NSR Modification”)
In Rule 100, Section 200.71(c) (Definition of “Minor NSR Modification”), the department is proposing to change “minor
NSR threshold” to “minor NSR modification threshold”.
SRP’s Attachment B Comment #3: Rule 100, Section 200.73 (Definition of “Modification”)
MCAQD proposes to add a definition of modification to the rules that mirrors the definition added by ADEQ in its most
recent rule revisions. This definition, however, is confusing because it defines activities differently from the definition of
“major modification” and “minor NSR modification”. For example, it uses the term “regulated air pollutant”, which includes
hazardous air pollutant (HAP) emissions, and exempts increases in operating hours (which should be included in the major
modification definition). It also uses the term “de minimis” and “minor source”, which are not defined in the rules.
MCAQD’s intent for this definition is not clear. For example in Rule 241, Section 306.4, the regulations require best
available control technology (BACT) for “the affected area in the case of a modification”. As written, the language could be
interpreted to require BACT for HAP emissions increases if a HAP modification occurs concurrently with a minor NSR
modification that requires BACT. The term “modification” also is used to describe changes to permits and model
substitution. The defined term “modification” makes no sense in these contexts. To prevent confusion, MCAQD should
remove the definition, or explain in the preamble how this definition interfaces with other types of modifications.
SRP’s Attachment B Response #3: Rule 100, Section 200.73 (Definition of “Modification”)
The definition of “modification” (in Rule 100) is proposed to be revised to be consistent with ADEQ’s NRS rules R18-2-
101(80) and the definition of “major modification” is proposed to be revised to be consistent with ADEQ’s NSR rules R18-2-
101(74). The department added definitions from statutes rather than incorporating by reference in order to facilitate EPA
approval of rules into the SIP. The definition of “modification” defines activities differently from the definition of “major
26

modification” and the definition of “minor NSR modification” because the definition of “modification” applies to Title V and
operating permit rules. The term “modification” as used in Rule 241 refers specifically to minor NSR modification.
SRP’s Attachment B Comment #4: Rule 100, Section 200.79 (Definition of “Physical Change”)
MCAQD proposes to retain its existing definition of physical change. However, this definition is confusing because it does
not contain the same exclusions as provided in the definition of major modification, minor NSR modification, and
modification. To prevent this confusion, MCAQD should remove the definition.
SRP’s Attachment B Response #4: Rule 100, Section 200.79 (Definition of “Physical Change”)
The department is proposing to delete the definition of “physical change” from Rule 100.
SRP’s Attachment B Comment #5: Rule 210, Section 301.8 (Action On Application)
MCAQD proposes to remove the time frames under which MCAQD is required to take proposed and final action on permit
applications. While ADEQ may have removed this language from its rules because they address the timeframes elsewhere in
their licensing timeframes, MCAQD has not adopted these licensing provisions. At any rate, MCAQD has not explained or
justified its basis for removing these provisions from the Title V requirements. Therefore, MCAQD should not finalize these
proposed changes.
SRP’s Attachment B Response #5: Rule 210, Section 301.8 (Action On Application)
In Rule 210, Sections 301.8(f) and (h) (Action On Application), the department is proposing to remove the proposed deletion
of these sections. The department is proposing to retain the original text of Rule 210, Sections 301.8(f) and (h).
SRP’s Attachment B Comment #6: Rule 220, Section 302.24 (Permit Contents)
MCAQD proposes to add a provision that provides it authority to deny a permit renewal application and take other actions on
a permit for any permit non-compliance. This statement provides the Director with overly broad discretion that is not
properly bounded with reasonable procedures for determining when such extreme actions are warranted. Such an action is not
justified for all degrees of non-compliance. As written, mailing a required report to the wrong address could result in permit
revocation or failure to renew a permit. The provision is also not bounded in time. Non-compliance that has been identified
and resolved without reoccurrence should not be a basis to withhold a permit approval. SRP recommends MCAQD delete
this provision and similar provisions in other parts of its rules. If MCAQD retains these provisions, then MCAQD must, at a
minimum, bound its discretion by explaining how it will reasonably implement this provision in the preamble to the final
rule.
SRP’s Attachment B Response #6: Rule 220, Section 302.24 (Permit Contents)
Rule 220, Section 302.24 matches ADEQ’s NSR rules R18-2-306(A)(8). The department is bound by the provisions in Rule
200, Sections 401 (Approval or Denial of Permit or Permit Revisions) and 402 (Permit Reopenings; Revocations and
Reissuance; Termination).
SRP’s Attachment B Comment #7: Rule 230, Section 306.2 (General Permit Renewal)
MCAQD proposes to terminate a source’s right to operate under a general permit if the general permit expires. This creates a
potential gap if MCAQD fails to issue an individual permit for a source within 180 days of providing notice of cancellation.
Under such circumstances, MCAQD should provide an application shield to applicants that allows them to continue to
operate consistent with its application.
SRP’s Attachment B Response #7: Rule 230, Section 306.2 (General Permit Renewal)
In Rule 230, Section 306.3, the department is proposing to delete the proposed sentences “Until such time that a timely
application is submitted, the source shall continue to comply with the previously issued general permit coverage. Upon
submittal of a timely application, the source shall comply with the renewed permit” and to add “If a source submits a timely
and complete application for a permit renewal, but the Control Officer has failed to issue or deny the renewal permit before
the end of the term of the previous permit, then the permit shall not expire until the permit renewal has been issued or denied”
SRP’s Attachment B Comment #8: Rule 240, Section 303.3 (Action on Application and Notification Requirements)
MCAQD proposes language that requires sources to request a construction extension if construction does not begin within 18
months from the permit issuance date. In finalizing this provision, MCAQD should confirm in the preamble that it intends to
implement this provision consistent with EPA’s recently issued guidance (Guidance on Extension of Prevention of
Significant Deterioration (PSD) Permits under 40 CFR 52.21(r)(2) January 31, 2014). This guidance provides a reasoned
approach for granting extensions.
SRP’s Attachment B Response #8: Rule 240, Section 303.3 (Action on Application and Notification Requirements )
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The department included in the Preamble of this notice that the department intends to implement provisions consistent with
the EPA’s “Guidance on Extension of Prevention of Significant Deterioration (PSD) Permits under 40 CFR 52.21(r)(2)”,
January 31, 2014).
SRP’s Attachment B Comment #9: Rule 240, Section 305.1 (Permit Requirements for New Major Sources or Major
Modifications Located in Attainment or Unclassifiable Areas)
MCAQD proposes to exclude 40 CFR § 52.21(i) from its incorporation by reference of the Federal major NSR rules. These
provisions define conditions under which major NSR does not apply. MCAQD has not explained the basis for its proposed
exclusion of these exemptions from its major NSR regulations. MCAQD should remove this exclusion from this section.
SRP’s Attachment B Response #9: Rule 240, Section 305.1 (Permit Requirements for New Major Sources or Major
Modifications Located in Attainment or Unclassifiable Areas)
In Rule 240, Section 305.1(d)(1) (Permit Requirements For New Major Sources Or Major Modifications Located In
Nonattainment Areas), the department is proposing to remove (i) from the list of cited 40 CFR 52.21 paragraphs.
SRP’s Attachment B Comment #10: Rule 240, Section 305.2 (Permit Requirements for New Major Sources or Major
Modifications Located in Attainment or Unclassifiable Areas-Additional Requirements)
MCAQD proposes language that essentially mirrors the Federal regulations at 40 CFR § 51.165(b)(2). However, paragraph
(a) alters the federal regulatory language in a manner that makes the requirements less clear and potentially more stringent.
MCAQD’s proposed language would require a source to show that it does not cause or contribute to increased ambient
concentrations rather than show that it does not cause or contribute to the NAAQS exceedance. While paragraph (b) in the
proposed MCAQD rules references EPA’s de minimis emission rates in 40 CFR § 51.165(b), paragraph (a) could be
interpreted to find that a source causes or contributes whenever ambient concentrations increase, regardless of whether that
increase is significant or paired in time and space with the actual NAAQS violation. The proposed rule should be revised to
clarify that the demonstration is with respect to whether the source will “cause or contribute to a violation”, consistent with
40 CFR § 51.165(b)(1) and (b)(2). This section also contains two typographical errors. First, the rules cross reference 40
CFR 51.165(a)(11)(b)(2), but should cross reference 40 CFR 51.165(b)(2). Second, paragraph (d) appears to be missing the
word “area” before “designated”.
SRP’s Attachment B Response #10: Rule 240, Section 305.2 (Permit Requirements for New Major Sources or Major
Modifications Located in Attainment or Unclassifiable Areas-Additional Requirements)
In Rule 240, Section 305.2, the department is proposing to delete “additional” from the section heading. In Rule 240, Section
305.2(a), the department is proposing to change the phrase “would not cause or contribute to an increase in ambient
concentrations for a pollutant” to “would not cause nor contribute to a violation of a NAAQS for a pollutant”. In Rule 240,
Section 305.2(b), the department is proposing to delete “to a major source” and changed “40 CFR 51.165(a)(11)(b)(2)” to
“40 CFR 51, 165(b)(2)”. In Rule 240, Section 305.2(c), the department is proposing to delete “to a major source”. In Rule
240, Section 305.2(d), the department is proposing to delete “as” from the phrase “in designated nonattainment areas”.
SRP’s Attachment B Comment #11: Rule 241, Section 102 (Applicability)
The applicability section is confusing because Section 102.1 and 102.2 seem to stand alone from Section 102.3 and 102.4,
when in fact Section 102.3 and 102.4 describe the types of construction and minor NSR modifications that MCAQD intends
to regulate under the rule. As written, the rule applies to any modification or construction of a source since the definition of
construction includes modification, and the term source is defined to include both an emissions unit and a stationary source.
SRP suggests that MCAQD amend the language to include the language in Sections 101.1 and 101.2 in the opening
paragraph of Section 102, and then add the word “when” to introduce Sections 102.3 and 102.4. The revised section would
read: 102 APPLICABILITY: Except as provided in Section 103, the provisions of this rule shall apply to the construction of
any new Title V or Non-Title V source, and any minor NSR modification to a Title V or Non-Title V source, when:
102.1 A regulated minor NSR pollutant emitted by a new stationary source, if the source will have the potential to emit that
pollutant at an amount equal to or greater than the permitting threshold, or
102.4 An increase in emissions of a regulated minor NSR pollutant from a minor NSR modification, if the modification
would increase the source’s potential to emit that pollutant by an amount equal to or greater than the minor NSR modification
threshold.
SRP’s Attachment B Response #11: Rule 241, Section 102 (Applicability)
In Rule 241, Section 102 (Applicability), the department is proposing to clarify the types of construction and minor NSR
modifications that are regulated by Rule 241. The department is proposing to include the language in Sections 102.1 and
102.2 in the opening paragraph of Section 102 and is proposing to add the word “when” to introduce Sections 102.3 and
102.4 (and to re-number Sections 102.3 and 102.4 to 102.1 and 102.2). In the previously numbered Section 102.4 (now
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numbered Section 102.2), the department is proposing to change the phrase “potential to emit” to “maximum capacity to
emit”.
SRP’s Attachment B Comment #12: Rule 241, Section 306.4 (BACT Determinations)
The regulation requires that BACT address emissions from the entire facility, or “the affected area in the case of a
modification”. The term “affected area” is undefined and ambiguous. MCAQD’s existing regulations are much clearer.
Therefore, MCAQD should retain the language from its existing regulations, which states: “BACT is only required for the
sources or group of sources being modified”. To address new sources, the phrase “constructs or” can be inserted in front of
“modified”.
SRP’s Attachment B Response #12: Rule 241, Section 306.4 (BACT Determinations)
To be consistent with text in Rule 241, Section 304.2 (BACT Required), the department is proposing to change, in Rule 241,
Section 306.4 (BACT Determinations), the phrase “the control of each emission point for the subject pollutant at a facility or
the affected area” to “the source or group of sources being modified”.
SRP’s Attachment B Comment #13: Rule 241, Section 313 (Permit Conditions Specified Pursuant to This Rule)
This section requires MCAQD to include conditions established under Rule 241 in subsequent permit renewals unless those
conditions are modified by Rule 241 or 240. This language is too restrictive as other permit change pathways may be
appropriate. For example, if an emissions unit is removed from the stationary source, an administrative amendment would be
appropriate in lieu of an action under Rule 241 or 240 to change the permit. SRP suggests that MCAQD modify the proposed
language to instead state: “unless modified through an appropriate permit process”.
SRP’s Attachment B Response #13: Rule 241, Section 313 (Permit Conditions Specified Pursuant to This Rule)
Rule 241, Section 313 matches ADEQ’s NSR rules R18-2-334(J).
14. Other matters prescribed by statute that are applicable to the specific department or to any specific rule or class of
rules
Not applicable
15. Incorporations by reference and their location in the rules:
Rule 240, Section 305.1: Subparts of 40 CFR 51.100; 40 CFR 51.166(p); 40 CFR 51.301; 40 CFR 52.21
Rule 240, Section 306.1: Subparts of 40 CFR 51.100(gg), (hh), (ii), (jj), and (kk)
Rule 510, Section 310: CFR references incorporated by reference in Appendix G
16. Were the rules previously emergency rules?
No
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