United States Environmental Protection Agency, Region IX 

Air Division 

Technical Support Document 

for 

EPA's Notice of Proposed Rulemaking 

for the 

California State Implementation Plan 

San Joaquin Valley Air Pollution Control District 

Rule 2020 Exemptions 

Rule 2201 New and Modified Stationary Source Review 

Roger Kohn 

Reviewed by Gerardo Rios 

November 15, 2011 
Table of Contents

Section Page

Introduction 1 

NSR Program SIP Revision Submittals 1 

Background 1 

Rule Summaries 2 

Rule 2020 – Exemptions

Rule 2201 – New and Modified Stationary Source Review Rule

Rule Evaluation 2 

Rule 2020 – Exemptions

Rule 2201 – New and Modified Stationary Source Review Rule

Section 110(l) of the Act 4 

Recommendations 4 

 
1 

Introduction

Part C of title I of the Clean Air Act (CAA or Act) contains the provisions for the Prevention of 

Significant Deterioration of air quality in areas designated as “attainment” or “unclassifiable” for 

the national ambient air quality standards (NAAQS). Part D of title I of the Act contains the 

requirements for areas designated “nonattainment” for any of the NAAQS. Both parts C and D 

of the Act require pre-construction permit programs for certain new or modified stationary 

sources of pollutants. The requirements under part C, referred to as “PSD New Source Review” 

(PSD) apply to certain new or modified sources that would be located within attainment areas, 

and apply to all regulated pollutants, except those pollutants for which an area has been 

designated as “nonattainment.” The requirements under part D, referred to as “Nonattainment 

NSR,” (NSR) apply to certain new or modified sources of nonattainment pollutants in 

nonattainment areas. Collectively, the pre-construction permit requirements related to PSD and 

Nonattainment NSR are commonly referred to simply as “NSR.” Both of these programs apply 

to “major” stationary sources and “major modifications” as those terms are defined in 40 CFR 

Part 51, Subpart I. In addition to the regulation of major stationary sources, states are also 

required to adopt a program to provide for the regulation of the construction and modification of 

minor stationary sources and minor modifications at major sources, to assure that the NAAQS 

are achieved and/or maintained. These pre-construction requirements are commonly referred to 

as “minor NSR.” (See 40 CFR 51.160-164)

NSR Program SIP Revision Submittals

Rule 2020 – Exemptions was amended by the San Joaquin Valley Unified Air Pollution Control 

District (SJVUAPCD or District) on August 18, 2011 and submitted to EPA via the California 

Air Resources Board (CARB) by a letter dated September 28, 2011. CARB is the governor’s 

designee for submitting official revisions of the California State Implementation Plan (SIP) to 

EPA. Submitted Rule 2020 specifies emission units that are not subject to District NSR permit 

requirements. 

Rule 2201 – New and Modified Stationary Source Review Rule was amended by the District on 

April 21, 2011 and submitted to EPA via the CARB by a letter dated May 19, 2011. Submitted 

Rule 2201 contains nonattainment pre-construction review requirements for minor and major 

stationary sources. 

Background

On May 11, 2010 (75 FR 26102), EPA took final action on revisions to the San Joaquin Valley 

Air Pollution Control District portion of the California State Implementation Plan. In that 

rulemaking, we finalized a limited approval and limited disapproval of the District’s NSR rules 

because we found two specific deficiencies related to enforceability of Rules 2020 and 2201 that 

prevented our full approval. Both rules contained references to California Health and Safety 

Code (CH&SC) under circumstances where the State law has not been submitted to EPA for 

approval into the SIP. In our final rule, we explained that the District could remedy these 

deficiencies by replacing the statutory reference to CH&SC sections with clear language that 
2 

does not rely on a cross-reference to State law, or submitting the State law provisions as a SIP 

revision. EPA is now acting on CARB’s submittal of Rules 2020 and 2201, which the District 

amended to resolve the deficiencies we identified in our May 11, 2010 final rule. 

In addition to addressing these deficiencies, we are also proposing to approve revisions to Rule 

2201 that address the 1997 PM2.5 standard. These revisions ensure that new major sources of 

PM2.5, and major modifications at existing major PM2.5 sources, will undergo pre-construction 

review that requires permit applicants to apply Lowest Achievable Emission Rate (LAER) and 

provide emission offsets. 

Rule Summaries

Rule 2020 – Exemptions 

The purpose of District Rule 2020 (“Exemptions”) is to specify emission units that are not 

required to obtain an Authority to Construct or Permit to Operate. Rule 2020 also specifies the 

recordkeeping requirements to verify such exemptions and outlines the compliance schedule for 

emission units that lose their exemption status. 

Rule 2201– New and Modified Stationary Source Review Rule 

The purpose of District Rule 2201 (“New and Modified Stationary Source Review Rule”) is to 

provide for the review of new and modified stationary sources of air pollution and to provide 

mechanisms, including control technology requirements and emission offsets, by which 

Authorities to Construct for such sources may be granted, without interfering with the attainment 

or maintenance of ambient air quality standards. District Rule 2201 is also intended to provide 

for no net increase in emissions above specified thresholds from new and modified stationary 

sources of all nonattainment pollutants and their precursors. 

Rule Evaluation

For this Technical Support Document (TSD), we have reviewed the revisions to District Rules 

2020 and 2201 to ensure that the District addressed the deficiencies we identified in our May 11, 

2010 final rule. 

Rule 2020

EPA found Rule 2020 deficient because the permitting exemption for agricultural sources relied 

on a cross-reference to CH&SC Section 42301.16, which is not approved in the SIP and allows 

permitting authorities to expand the universe of exempted sources if certain findings are made in 

a public hearing, which would change the permit exemption threshold without requiring SIP 

approval. To address this deficiency, the District revised Rule 2020 by replacing the statutory 

reference to CH&SC section 42301.16 in paragraph 6.20 with a clear description of the sources 

covered by the exemption. Paragraph 6.20 now describes the exemption without crossreferencing state law. The rule exempts “agricultural sources at a stationary source that, in 

aggregate, produce actual emissions less than one-half of the major source thresholds.” The 
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revised rule also requires that fugitive emissions (except fugitive dust emissions) be included in 

determining aggregate emissions. This amendment resolves the deficiency. 

In addition to resolving the deficiency, the District also added an exemption for wind machines, 

and a definition of “wind machine,” to Rule 2020 (“a machine consisting of a large fan mounted 

on a tower and powered by an internal combustion engine, used exclusively to provide frost 

protection to agricultural crops by affecting a heat transfer by moving warmer atmospheric air 

downward and mixing it with the colder air surrounding a crop.”). Annual usage varies naturally 

with the frequency and duration of cold spells in the San Joaquin Valley during any given winter; 

however, the District estimates average annual use of any given wind machine at 35 hours per 

year. Emissions per unit vary depending upon the size of the engine used to power the fans and 

the fuel used to power the engine, among other factors, but can reasonably be estimated at 

approximately 15 pounds per day of NOx.

1

 

EPA recognizes that, when the applicable frost warnings occur, the number of wind machines 

that operate all night long in certain parts of the valley can number in the thousands, and that 

NOx emissions during those particular nights are not necessarily insignificant from the standpoint 

of PM10 and PM2.5 formation, particularly in the San Joaquin Valley. Nonetheless, we can 

conclude that the permitting exemption for the wind machines is acceptable because wind 

machines are not subject to any prohibitory District rule,

2

because no emission controls would 

approach any reasonable threshold of cost-effectiveness given the very limited use of the 

machines and the low emissions per unit, and because neither the EPA-approved San Joaquin 

Valley PM10 maintenance plan nor the EPA-approved PM2.5 attainment plan relies on emissions 

reductions from this particular episodic source of emissions. 

Rule 2201

EPA also found Rule 2201 deficient because the offset exemption for minor agricultural sources 

was ambiguous because it relied on a cross-reference to the CH&SC, rather than explicitly 

delineating the exemption within the rule itself. The District remedied this deficiency by 

replacing the CH&SC references with a clear description of the applicability of the offset 

requirement to agricultural sources. The amended version of Rule 2201 clearly states that the 

offset exemption does not “apply to an agricultural source that is also a major stationary source 

for the pollutant for which the offset exemption is sought.” The replacement of the crossreferences to the CH&SC with this language resolves the deficiency. 

The District also added requirements to Rule 2201 to address the 1997 PM2.5 standard. EPA 

notes that SIP submittals from States to address the 1997 PM2.5 standard were due by June 15, 

2011. Thus at the time that the District submitted Rule 2201 in March 2009, the new PM2.5 

requirements were not yet due. The District subsequently met the deadline by including PM2.5

provisions in the rule that it submitted to EPA (via CARB) on May 19, 2011. We have reviewed 

 

1

 Most engines are fired on propane, although some are fired on diesel. Some engines are electric, and have no 

emissions. Based on a NOx emission factor for uncontrolled propane and use of a 100-horsepower engine at 65% 

load from 8:00 p.m. to 7:00 a.m.: 100 hp x 10 g NOx/bhp-hr x 0.65 x 11 hours/day / 454 g/lb = 15.8 pounds per day 

per unit. 

2

 See District Rule 4702 (“Internal Combustion Engines - Phase 2”), most recently approved by EPA at 73 FR 1819 

(January 10, 2008). 
4 

the PM2.5 provisions of the rule, including the addition of a definition of PM2.5 (subsection 3.28), 

the inclusion of PM2.5 in the definition of “affected pollutants” (subsection 3.4, which ensures 

that BACT, i.e., Federal LAER, applies to PM2.5), the addition of PM2.5 to the major source and 

significance thresholds (subsections 3.24.1 and 3.18.1.4, respectively), and the application of 

emission offset requirements to PM2.5 (including ratios based on distance from the new or 

modified emission unit, in subsections 4.5.4 and 4.8.2, respectively), and found that they satisfy 

the CAA requirements for NSR for new and modified stationary sources. 

We note that Rule 2201 has provisions allowing interpollutant offsets, including offsets between 

PM2.5 and PM2.5 precursors, which the rule allows “at specific ratios as established by US EPA, 

or as approved into the State Implementation Plan by the US EPA” (Subsection 4.13.3.2). In a 

memorandum dated July 21, 2011, EPA revised its policy regarding the development and 

adoption of interpollutant trading provisions for PM2.5 under NSR programs in PM2.5

nonattainment areas.3 Under the revised policy, any ratio involving PM2.5 precursors submitted to 

EPA for approval for use in a state's interpollutant offset program for PM2.5 nonattainment areas 

must be accompanied by a technical demonstration that shows the net air quality benefits of such 

ratio for the PM2.5 nonattainment area in which it will be applied. Neither the staff report 

submitted with Rule 2201 nor the District’s PM2.5 attainment plan includes any such technical 

demonstration. As a result, EPA interprets Rule 2201 to not allow offsets between PM2.5 and 

PM2.5 precursors unless EPA approves a specific ratio into the SIP, either in a revised version of 

Rule 2201 or in an attainment plan. 

Section 110(l) of the Act

CAA section 110(l) precludes EPA from approving SIP revisions that would interfere 

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

any other applicable requirement of the Act. EPA has evaluated amended Rules 2020 and 2201 

and concluded that they would not interfere with attainment and RFP for any of the NAAQS, and 

would not interfere with any other applicable requirement of the Act. First, amended Rule 2201 

does not relax the SIP in any aspect; rather, the amended rule strengthens the SIP by applying 

NSR requirements to new or modified major sources of PM2.5. Second, while amended Rule 

2020 contains a new exemption for wind machines, this exemption would not lead to an increase 

in emissions because even if no such exemption were in effect, wind machines would not be 

subject to any emission control requirements under the NSR rule because no control device 

would be considered cost-effective. Lastly, neither the EPA-approved San Joaquin Valley PM10

maintenance plan nor the EPA-approved PM2.5 attainment plan relies on emissions reductions 

from this particular episodic source of emissions. The two SIP revisions would be acceptable 

under CAA section 110(l). 

Recommendations

Pursuant to section 110(k)(3) of the Act, we recommend a full approval of the submitted NSR 

rules. We recommend approval of the submitted NSR rules based on our determination that the 

 

3

http://www.epa.gov/Region7/air/nsr/nsrmemos/pm25trade.pdf (URL as of October 14, 2011) 
5 

rules comply with applicable statutory and regulatory provisions requiring regulation of 

stationary sources in general and requiring permit programs for major stationary sources in 

particular, including section 110(a)(2)(C) and part D of title I of the Act. 

In support of this recommendation, we have concluded that our approval of Rule 2020 and Rule 

2201 complies with section 110(l) of the Act because the amended rules do not relax control 

technology and offset requirements and therefore would not interfere with the strategy for 

attainment of the Ozone, PM2.5, or Carbon Monoxide NAAQS in SJVUAPCD or the continued 

attainment of the other NAAQS in SJVUAPCD. If we finalize this action as proposed, our action 

would be codified through revisions to 40 CFR 52.220 (“Identification of plan”).