United States Environmental Protection Agency, Region 9 

Air Division 

Technical Support Document 

for 

EPA’s Notice of Proposed Rulemaking 

for the 

California State Implementation Plan 

South Coast Air Quality Management District’s 

Rule 1147, NOx Reductions from Miscellaneous Sources 

Prepared by: Idalia Pérez 

June 2010 
South Coast Air Quality Management District (SCAQMD) 

Submitted Rule 

SCAQMD Rule 1147, NOx Reductions from Miscellaneous Sources 

 Adopted: December 5, 2008 

 Submitted: May 17, 2010 

 Determined complete: June 8, 2010 

Previous Rule Submittals 

There are no outstanding submittals of Rule 1147. 

SIP-Approved Rule 

Rule 1147 has not been previously approved into the SIP. 

Rule Summary 

Rule 1147 limits NOx from a variety of gas and liquid fired combustion equipment that require a 

District permit and are not specifically required to comply with a NOx emission limit by other 

District Regulation XI rules. 

The emission limits for NOx, which range between 30 ppm and 60 ppm depending on equipment 

type and process temperature, are in Table 1 of Section (c)(1). Other requirements of the Rule 

include mandatory system maintenance and installation of fuel and time meters. 

Compliance for in-use units, which is presented in Table 2, is phased in starting with older 

equipment. New, modified or relocated units have to be in compliance by January 1, 2010. 

Compliance can be achieved by certification, for units which do not allow of adjustment of fuel 

and combustion air, or by emission determinations pursuant to an approved test protocol. 

Effects on Emissions 

The District estimates that NOx emission reductions due to Rule 1147 are 3.5 tons per day by 

2015 with an additional 0.3 tons per day reduction expected by 2023. 

Rule Evaluation 

Generally, SIP rules must be enforceable (see §110(a) of the Clean Air Act, hereafter CAA); must 

require Reasonably Available Control Technology (RACT) for major sources of NOx in 

nonattainment areas (see CAA §182(b)(2) and (f)); must not interfere with applicable requirements, 

including requirements concerning attainment (see CAA §110(l)); and must not relax existing 

requirements in effect prior to enactment of the 1990 CAA amendments (see §193). 

SCAQMD regulates a serious (8-hour) and extreme (1-hour) ozone nonattainment area (40 CFR 

81), thus SCAQMD must ensure RACT. Guidance and policy documents that we used to define 

specific enforceability and RACT requirements include the following: 

• Issues Relating to VOC Regulation, Cutpoints, Deficiencies, and Deviations (the "Blue 

Book"), US EPA, OAQPS (May 25, 1988). 

• Guidance Document for Correcting Common VOC and Other Rule Deficiencies, EPA 

Region IX (August 21, 2001, the “Little Bluebook”).
• State Implementation Plans; General Preamble for the Implementation of Title I of the 

Clean Air Act Amendments of 1990, 57 FR 13498 (April 16, 1992); 57 FR 18070 (April 

28, 1992). 

• State Implementation Plans; Nitrogen Oxides Supplement to the General Preamble; 

Clean Air Act Amendments of 1990 Implementation of Title I; Proposed Rule, (the NOx 

Supplement), 57 FR 55620, November 25, 1992. 

• Determination of Reasonably Available Control Technology and Best Available Retrofit 

Control Technology for Industrial, Institutional, and Commercial Boilers, Steam 

Generators, and Process Heaters, CARB (July 18, 1991). 

http://www.arb.ca.gov/ractbarc/boilers.pdf

• Alternative Control Techniques Document-- NOx Emissions from 

Industrial/Commercial/Institutional (ICI) Boilers, US EPA 453/R-94-022 (March 1994). 

http://www.epa.gov/ttn/catc/dir1/icboiler.pdf

• Alternative Control Techniques Document-- NOx Emissions from Utility Boilers, US 

EPA 452/R-93-008 (March 1994). http://www.arb.ca.gov/ractbarc/boilers.pdf

Based on Table 2-3 of the Final Environmental Assessment, the NOx emissions of the units 

subject to this Rule are too small to exceed the major source threshold and are therefore likely 

not subject to RACT. Even if RACT were required, we believe SCAQMD Rule 1147 likely 

implements RACT for NOx emissions for reasons including: 

• As mentioned in the “Summary of Affected Equipment and Methods of Compliance” in 

the Environmental Assessment, compliance with emission limits in the Rule would be 

achieved primarily by installing ultra-low NOx burners which is state of the art 

technology for small combustion. 

• SCAQMD’s Rule 1147 is as or more stringent than SJVAPCD Rule 4309 which covers 

some of the sources subject to Rule 1147. SJVAPCD has among the most stringent 

stationary source requirements nationwide, and we are not aware of other reasonably 

available technological or operational controls likely to significantly reduce additional 

emissions from this activity. 

Since no CTG has been issued recently for this activity, we do not have clear national guidance 

defining presumptive RACT. However, we believe the analysis summarized above sufficiently 

demonstrates that Rule 1147 implements RACT for NOx. 

In addition, recordkeeping and other compliance provisions in the Rule ensure that the 

requirements are adequately enforceable. Lastly, since there is no version of submitted 

previously approved into the SIP, the submitted rule does not relax the SIP and complies with 

CAA §110(l) and §193. 

Suggested Rule Improvement 

EPA recommends that the SCAQMD make the following improvement in the next revision of 

Rule 1147, although this is not basis for rule disapproval at this time. 

1. The terms start up in Section (d)(1)(B) and as-found operating conditions in Section 

(d)(1)(C) should be clearly defined in the Rule. 

Recommendation 
EPA staff recommends approval of SCAQMD submitted Rule 1147 for incorporation into the 

California Applicable SIP. 

Attachments 

1. Submitted Rule 1147 

2. Staff Report