UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX AIR DIVISION

Technical Support Document

for

EPA’s Rulemaking

for the

Arizona State Implementation Plan

Arizona Department of Environmental Quality

Title 18, Article 3, Section R18-2-313

Existing Source Emission Monitoring

Prepared by: Stanley Tong

June 12, 2012
2

RULE IDENTIFICATION 

Agency: Arizona Department of Environmental Quality (ADEQ)

SIP Approved Rule: Rule R9-3-313 – Existing Source Emission Monitoring

Submitted – January 4, 1979, and

April 1, 1980, and

July 17, 1980

EPA Approved – April 23, 1982 (47 FR 17483)

Subject of this TSD: Rule R18-2-313 Existing Source Emission Monitoring

Amended -

Submitted – Expected August 2012

Purpose of Amended Rule – Section 110(a) of the Clean Air Act (CAA) requires states to 

submit regulations that control volatile organic compounds, oxides of nitrogen, particulate 

matter, and other air pollutants which harm human health and the environment. Rule R18-2-

313 was developed as part of the local agency’s program to monitor emissions of certain 

pollutants. Arizona Department of Environmental Quality (ADEQ) submitted this rule to support 

the infrastructure SIP requirements of section 110(a)(2) of the CAA.

BACKGROUND – ADEQ Rule R9-3-313, Existing Source Emission Monitoring, (July 17, 

1980), was approved into the Arizona State Implementation Plan on April 23, 1982 (47 FR 

17483). The rule contains minimum requirements for owners and operators to install, calibrate, 

operate and maintain continuous monitoring equipment at certain fossil-fuel fired steam 

generators, fluid bed catalytic cracking unit catalyst regenerators, sulfuric acid plants, and 

nitric acid plants.

Rule R9-3-313 was subsequently renumbered as R18-2-313. Rule R18-2-313 was last 

amended on March 9, 2001. Both the 1980 SIP approved version of the rule and the current 

SIP submittal largely parallel the requirements found in 40 CFR part 51, Appendix P, Minimum 

Emission Monitoring Requirements. The rules specify the source categories subject to 

emissions monitoring; contain requirements for recording and reporting data; reference 40 

CFR part 60, Appendix B, Performance Specifications for accuracy and reliability of 

acceptable monitoring systems; and contain equations to convert monitoring emissions data to 

units of the emission standards. 

RULE SUMMARY – In order to help determine compliance with applicable emission limits, 

Rule R18-2-313 requires fossil-fuel fired steam generators with an annual capacity factor 

greater than 30% that are subject to an opacity standard, and are greater than 250 MM Btu/hr 

to install, calibrate, operate, and maintain a continuous emission monitoring system to 

measure opacity. Certain exemptions from the requirement to install and maintain continuous 

emission monitors are allowed by the rule, such as where gaseous fuel is the only fuel burned,

or when oil or a mixture of oil and gas are the only fuels burned and the stationary source is 

able to comply with the particulate and opacity standards without the use of control equipment

for particulate matter. The rule also requires continuous emission monitoring systems to meet 
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the performance specifications in 40 CFR part 60, Appendix B, for sulfur dioxide, nitrogen 

oxides, and oxygen or carbon dioxide.

In addition to steam generators, Rule R18-2-313 also specifies the minimum requirements for 

continuous emission monitoring systems covered by the rule for nitrogen oxides at Nitric Acid 

plants, sulfur dioxide at Sulfuric Acid plants, and opacity at fluid bed catalytic cracking unit 

catalysts regenerators at petroleum refineries.

The Rule also contains requirements for calibration gases, measurement cycling times, 

monitoring locations, and recording zero and drift daily calibration checks.

The following significant amendments were made from the SIP approved version: 

1. Section A.3, Variances. The amended rule clarifies that extreme economic conditions are 

those conditions that "would cause the source to be unable to continue in business."

2. Section E, Minimum data requirement, was amended to update a citation from R18-2-310 to 

R18-2-310.01. R18-2-310.01, Reporting Requirements, was originally contained in R18-2-

310(C) and (D). These sections were moved to a new separate section, R18-2-310.01 to 

remove any ambiguities regarding the need and process for reporting an excess emission 

event.

EPA EVALUATION – Generally, prohibitory SIP rules must be enforceable (see section 110(a)

of the CAA) and must not relax existing requirements (see sections 110(l) and 193). We have 

evaluated this SIP revision to determine whether it would interfere with any applicable 

requirement concerning attainment and reasonable further progress (RFP) or any other 

applicable requirement of the Act (CAA 110(l)). 

EPA guidance documents that we used to help evaluate enforceability requirements 

consistently includes the following:

• Requirements for Preparation, Adoption, and Submittal of Implementation Plans, U.S. 

EPA, 40 CFR part 51.

• Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations, EPA (May 

25, 1988) (The Bluebook).

The submitted SIP revision is more stringent than the rule previously approved into the SIP and 

would not interfere with any applicable requirement concerning attainment and reasonable 

further progress (RFP) or any other applicable requirement of the Act (CAA 110(l)) or modify, in 

a nonattainment area, any SIP-approved control requirement in effect before November 15, 

1990 (CAA 193).

The submitted rule contains recordkeeping and reporting requirements and performance 

specifications that generally ensure that the submitted rule can be enforced. 

RECOMMENDATIONS FOR THE NEXT RULE REVISION - The following revisions are 

recommended for the next time the rule is amended but do not interfere with approval of this 

rule at this time.
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1. Section D.1.d – typographical error

This section states continuous emission monitoring systems for measuring sulfur dioxide shall 

comply with performance specification 3. The term "sulfur dioxide" in this section should be 

changed to "oxygen" to be consistent with Section F.1.c (see legend for %O(2), %CO(2) cite to 

subsection (D)(1)(d)), and consistent with the SIP approved rule R-9-3-313 section D.1.d and 

40 CFR part 51 Appendix P section 3.1.4.

2. Section D.6 – typographical error

Please insert the word "and" between "zero" and "span" in the fifth line:

... recommendations shall be followed; shall adjust the zero span whenever the...

3. Section F1.a.ii – typographical errors

The second equation under ii contains an error. The 29.9 should be changed to 20.9; there 

should be a "minus sign" in front of the %O(2ws) in the first equation; and B(wa) should be 

B(ws) in both equations under F1.a.ii.

















20.9(1 ( ))% (2 )

20.9

( ) ( )

B wa O ws

E Q C ws F

 

should instead be: 













 



20.9(1 ( )) % (2 )

20.9

( ) ( )

B ws O ws

E Q C ws F













29.9(1 ( ))  % (2 )

20.9

B wa O ws

should instead be: 













20.9(1 ( ))  % (2 )

20.9

B ws O ws

4. ADEQ may want to determine if there are continuous emissions monitoring systems at 

stationary sources that should be covered by, but are not currently subject to Rule R18-2-313 

and amend Rule R18-2-313 as appropriate. If R18-2-313 is amended, ADEQ should also

review, and incorporate as appropriate, the administrative and technical requirements in South 

Coast AQMD Rule 218 – Continuous Emission Monitoring and Rule 218.1 – Continuous 

Emission Monitoring Performance Specifications.

EPA RECOMMENDED ACTION – We recommend full approval of Rule R18-2-313. 
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REFERENCES -

1. ADEQ Rule R18-2-313, Existing Source Emission Monitoring, submittal expected 

August 2012.

2. ADEQ Rule R9-3-313, Existing Source Emission Monitoring, as approved into the SIP 

on April 23, 1982 (47 FR 17483). 

3. “Requirements for Preparation, Adoption, and Submittal of Implementation Plans, U.S. 

EPA, 40 CFR part 51.

4. Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations, EPA (May 

25, 1988) (The Bluebook).

5. 40 CFR part 51, Appendix P.

6. EPA-450/2-78-042a, October 1978, Stack Sampling Technical Information – A 

Collection of Monographs and Papers Volume 1 http://www.epa.gov/ttn/emc/informd/tid020.pdf