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

Imperial County Air Pollution Control District’s

Rule 400.1, Stationary Gas Turbine(s) – Reasonably Available Control Technology (RACT)

Prepared by: Idalia Perez

December 2011
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Imperial County Air Pollution Control District (ICAPCD)

Submitted Rule

ICAPCD Rule 400.1, Stationary Gas Turbine(s) – Reasonably Available Control Technology 

(RACT)

 Adopted: February 23, 2010

 Submitted: July 20, 2010

 Determined complete: August 25, 2010

Previous Rule Submittals

There are no outstanding submittals of Rule 400.1.

SIP-Approved Rule

There is no SIP-approved version of Rule 400.1.

Rule Summary

Rule 400.1 regulates emissions of oxides of nitrogen (NOx) from stationary gas turbine systems 

with ratings equal to or greater than 1 MW.

The emission limits in the rule are (Section C):

 42 ppm for units operated on gaseous fuel

 65 ppm for units operated on liquid fuel

The rule language includes exemptions (Section D). Monitoring and recordkeeping requirements 

are contained in various provisions in Sections E, F, G and H.

Impact on Emissions

According to documentation included with the rule submittal, the District does not expect a 

reduction in emissions due to the implementation of this rule because all existing sources subject 

to the rule are already able to comply with the emission limits without installing further control 

technology.

Rule Evaluation Criteria 

We have primarily used the following three criteria to evaluate Rule 400.1:

Rule Stringency Section 172(c)(1) of the Clean Air Act (CAA) requires nonattainment 

areas to implement all reasonably available control measures (RACM), including such

reductions in emissions from existing sources in the area as may be obtained through the 

adoption, at a minimum, of reasonably available control technology (RACT), as 

expeditiously as practicable. Ozone nonattainment areas classified as moderate or above 

must require RACT for all major sources of NOx. CAA § 182(b)(2) & (f); 40 CFR § 

51.912(a). In addition, SIP rules must implement RACM, including RACT, in moderate 

PM-10 nonattainment areas, and Best Available Control Measures (BACM), including 

Best Available Control Technology (BACT), in serious PM-10 nonattainment areas (see 

CAA sections 189(a)(1) and 189(b)(1)). The ICAPCD regulates an ozone nonattainment 

area classified as moderate (see 40 CFR part 81). Because Rule 400.1 regulates major 
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stationary sources of NOx, it must fulfill NOx RACT requirements. On December 3 

2009, EPA determined that ICAPCD attained the 1997 8-hour NAAQS for ozone based 

upon ambient air monitoring data showing the area had monitored attainment during the 

2006-2008 monitoring period. (74 FR 63309) This determination suspended some of the 

planning requirements related to attainment of the 1997 8-hour ozone NAAQS but not 

the Section 182(b)(2) and 182(f) RACT requirements for major NOx emission sources.

The ICAPCD also regulates a serious PM-10 nonattainment area, and is therefore subject 

to the requirement under sections 189(b)(1)(B) and 189(e) of the Act to implement Best 

Available Control Measures (BACM, which includes BACT) for control of PM-10 and 

PM-10 precursor emissions.1

Enforceability CAA section 110(a)(2)(A) requires that regulations submitted to EPA for 

approval into a State Implementation Plan (SIP) must be clear and legally enforceable. 

SIP Revisions CAA section 110(l) prohibits EPA from approving any SIP revision that 

would interfere with any applicable requirement concerning attainment and reasonable 

further progress (RFP) or any other applicable requirement of the CAA. In addition, CAA 

section 193 prohibits the modification of any SIP-approved control requirement in effect 

before November 15, 1990, in a nonattainment area.

Guidance and policy documents that we used to define specific enforceability and RACT, 

RACM and BACM 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 for 

the Implementation of Title I of the Clean Air Act Amendments of 1990 (the "NOX

Supplement to the General Preamble"), US EPA, 57 FR 55620 (November 25, 1992).

 Clean Air Fine Particle Implementation Rule, 72 FR 20586 (April 25, 2007)

 State Implementation Plans for Serious PM-10 Nonattainment Areas, and Attainment 

Date Waivers for PM-10 Nonattainment Areas Generally; Addendum to the General 

Preamble for the Implementation of Title I of the Clean Air Act Amendments of 1990, 59 

FR 41998 (August 16, 1994).

 PM-10 Guideline Document, US EPA 452/R-93-008 (April 1993).

 

1

ICAPCD also regulates a nonattainment area under the 2006 24-Hour PM2.5 NAAQS. 40 C.F.R. § 81.305 (2010). 

By December 14, 2012, California must submit a revision to the State Implementation Plan (SIP) for this 

nonattainment area that provides for, among other things, implementation of all RACM as expeditiously as 

practicable (including RACT for existing sources). CAA § 172(a)(2)(A), (b) & (c)(1), 74 FR 58689 (Nov. 13, 2009). 

EPA will take action on this RACM demonstration in a separate rulemaking.
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 Alternative Control Technology Document, NOx Emissions from Stationary Gas 

Turbines, US EPA, 453/R-93-007 (January 1993)

http://www.epa.gov/ttncatc1/dir1/gasturb.pdf

 Determination of Reasonably Available Control Technology and Best Available Retrofit 

Control Technology for the Control of Oxides of Nitrogen from Stationary Gas Turbines, 

California Air Resources Board (May 18, 1992)

http://www.arb.ca.gov/research/apr/reports/l3092.pdf

 Status Report on NOx Controls for Gas Turbines, Cement Kilns, Boilers, and Internal 

Combustion Engines; Northeast States for Coordinated Air Use Management

(NESCAUM, December 2000) http://www.nescaum.org/documents/nox-2000.pdf

Evaluation of Rule Stringency

We believe Rule 400.1 implements RACT in Imperial County for reasons including:

- The 1993 ACT provides technical information including control techniques and 

achievable controlled NOx emission levels from stationary gas turbines. Rule 400.1

requirements are in alignment with levels of controls that the ACT shows are 

achievable. 

- Rule 400.1 requirements are the same as those determined to be RACT in the 1993 

ARB RACT/BARCT determination.

- The limits in the rule are consistent with what the 2000 report by NESCAUM 

determined to be feasible for retrofit installations. 

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 400.1 implements RACT. 

According to the 2009 PM10 SIP, fuel combustion accounts for less than 1% of the emission 

inventory for PM10 in Imperial County. Since turbines are not a significant source of PM10, we 

do not believe they are subject to BACM requirements and thus we are not making a 

determination on the Rule’s ability to implement BACM. 

Evaluation of Enforceability and SIP Revision Criteria 

Recordkeeping and other compliance provisions in the rule ensure that the requirements are 

adequately enforceable. 

The submitted is a new addition to the SIP, strengthening the requirements of the SIP. Therefore, 

we propose to determine that a approval of the submittal would comply with CAA sections

110(l) and 193 because (1) the proposed SIP revision would not interfere with the on-going 

process for ensuring that requirements for RFP and attainment of the NAAQS are met, and (2)

the submitted SIP revision is more stringent than the existing SIP requirements. 

Suggested Rule Improvements

Although not currently basis for rule disapproval, EPA recommends that the ICAPCD make the 

following improvements in the next revision of Rule 400.1.

1. While we believe this rule as drafted is sufficient to implement RACT, we encourage the 

District to consider more stringent emission limits that other California agencies have 
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determined are technically and economically feasible for similar sources. These limits are 

as low as 3 ppm for gas fired units and 25 ppm for liquid fired units. See, for example:

 Antelope Rule 1134 (adopted in 2010)

 Placer Rule 250 (adopted in 1994) 

 Sacramento Rule 413 (adopted in 2005)

 San Joaquin Rule 4703 (adopted in 2002)

 South Coast Rule 1134 (adopted in 1997)

 Ventura Rule 74.23 (adopted in 2002)

 Yolo-Solano Rule 2.34 (adopted in 1994)

2. The cutoff for a low use exemption in Section D.2.a should be lowered from 400 hours 

per calendar year to 200 hours per calendar year. See for example Ventura Rule 74.23 or 

Mojave Rule 1159.

3. The need for exemptions from NOx emission limits during start-up, shutdown and during 

periods of load-changing as well as the duration of these periods (Section D.2.b) should 

be justified in the District’s staff report submitted with the next version of the rule.

Additionally, the language of this section should not include “or as specified on the 

permit to operate.”

4. Section G.1 states: 

“If an owner or operator of a Stationary Gas Turbine demonstrates to the 

satisfaction of the APCO that the Stationary Gas Turbine cannot operate at these 

conditions, then emissions source testing shall be performed at the highest 

achievable continuous power rating.”

The Rule should be amended to follow EPA guidance on director’s discretion. One 

option for approvable provisions is to include EPA approval alongside APCO approval.

5. To facilitate compliance determinations, we recommend amending Section H to require 

that all records be maintained for 5 years.

Recommendation

Based on the discussion above, Rule 400.1 fulfills relevant Clean Air Act requirements for SIP 

approval and EPA staff recommends approval of ICAPCD Submitted Rule 400.1 for 

incorporation into the California Applicable SIP.

Other References

1. Submitted Rule 400.1

2. Staff Report