Alexis Strauss, Acting Regional Administrator, EPA Region 9 signed the following proposed rule on August 12, 

2014, and EPA is submitting it for publication in the Federal Register (FR). While we have taken steps to ensure the 

accuracy of this Internet version of the proposed rule, it is not the official version of the proposed rule for purposes 

of public comment. Please refer to the official version in a forthcoming FR publication, which will appear on the 

Government Printing Office's FDsys website (http://fdsys.gpo.gov/fdsys/search/home.action) and on 

Regulations.gov (http://www.regulations.gov) in Docket No. EPA-R09-OAR-2014-0185

Billing Code: 6560-50-P

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R09-OAR-2014-0612; FRL-_________]

Determination of Attainment of the 1-Hour Ozone National Ambient 

Air Quality Standard in the Southeast Desert Nonattainment Area

in California

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

SUMMARY: The Environmental Protection Agency (EPA) is proposing 

to determine that the Southeast Desert nonattainment area has 

attained the 1-hour ozone National Ambient Air Quality Standard.

This proposed determination is based on complete, qualityassured, and certified data for the most recent three-year 

period (2011-2013).

DATES: Any comments must arrive by [Insert date 30 days from the 

date of publication in the Federal Register].

ADDRESSES: Submit comments, identified by docket number EPA-R09-

OAR-2014-0612, by one of the following methods:

 Federal eRulemaking Portal: www.regulations.gov. Follow the 

on-line instructions.

 E-mail: kelly.thomasp@epa.gov.
2

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

 Mail or deliver: Tom Kelly, Office of Air Planning (AIR-2), 

U.S. Environmental Protection Agency Region IX, 75 

Hawthorne Street, San Francisco, CA 94105. 

Instructions: All comments will be included in the public 

docket without change and may be made available online at 

www.regulations.gov, including any personal information 

provided, unless the comment includes Confidential Business 

Information (CBI) or other information whose disclosure is 

restricted by statute. Information that you consider CBI or 

otherwise protected should be clearly identified as such and 

should not be submitted through www.regulations.gov or e-mail.

The www.regulations.gov website is an “anonymous access” system, 

and EPA will not know your identity or contact information 

unless you provide it in the body of your comment. If you send 

e-mail directly to EPA, your e-mail address will be 

automatically captured and included as part of the public 

comment. If EPA cannot read your comments due to technical 

difficulties and cannot contact you for clarification, EPA may 

not be able to consider your comment. 

Docket: The index to the docket for this action is available 

electronically on the www.regulations.gov website and in hard 

copy at EPA Region IX, 75 Hawthorne Street, San Francisco, 

California, 94105. While all documents in the docket are listed 
3

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

in the index, some information may be publicly available only at 

the hard copy location (e.g., copyrighted material or large 

maps), and some may not be publicly available at either location 

(e.g., CBI). To inspect the hard copy materials, please schedule 

an appointment during normal business hours with the contact 

listed in the FOR FURTHER INFORMATION CONTACT section below.

FOR FURTHER INFORMATION CONTACT: Tom Kelly, Air Planning Office 

(AIR–2), U.S. Environmental Protection Agency, Region IX, (415) 

972–3856, kelly.thomasp@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document, the terms

“we,” “us,” and “our” refer to EPA.

TABLE OF CONTENTS:

I. Background

II. EPA’s analysis

III. Proposed EPA Action and Request for Public Comment

IV. Statutory and Executive Order Reviews

I. Background

The Clean Air Act (CAA or “Act”) requires us to establish 

National Ambient Air Quality Standards (NAAQS or “standards”)

for certain widespread pollutants, such as ozone, that cause or 

contribute to air pollution that is reasonably anticipated to 

endanger public health or welfare (see sections 108 and 109 of 

the Act). In 1979, we promulgated an ozone NAAQS of 0.12 parts 
4

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

per million (ppm), one-hour average (“1-hour ozone standard”). 

See 44 FR 8202, February 8, 1979. 

An area is considered to have attained the 1-hour ozone 

standard if there are no violations of the standard, as 

determined in accordance with the regulation codified at 40 CFR 

section 50.9, based on three consecutive calendar years of 

complete, quality-assured and certified monitoring data. A 

violation occurs when the “expected number” of days per calendar 

year with maximum hourly average concentrations above 0.12 ppm 

is greater than one (1.0) at any site in the area, when averaged 

over three consecutive calendar years.1 An exceedance occurs when 

the maximum hourly ozone concentration during any day exceeds 

0.124 ppm. For more information, please see “National 1-hour 

primary and secondary ambient air quality standards for ozone”

(40 CFR 50.9) and “Interpretation of the 1-Hour Primary and 

Secondary National Ambient Air Quality Standards for Ozone” (40 

CFR part 50, appendix H).

The Act, as amended in 1990, required EPA to designate as 

nonattainment any ozone area that was still designated 

 

1 An “expected number” of exceedances is a statistical term that refers to an 

arithmetic average. An “expected number” of exceedances may be equivalent to 

the number of observed exceedances plus an increment that accounts for 

incomplete sampling. See, 40 CFR part 50, appendix H. Because, in this 

context, the term “exceedances” refers to days (during which the daily 

maximum hourly ozone concentration exceeded 0.124 ppm), the maximum possible 

number of exceedances in a given year is 365 (or 366 in a leap year).
5

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

nonattainment under the 1977 Act Amendments, and any other area 

violating the 1-hour ozone standard, generally based on air 

quality monitoring data from the 1987 through 1989 period 

(section 107(d)(4) of the Act; 56 FR 56694, November 6, 1991). 

The 1990 Amended Act further classified these areas, based on 

the severity of their nonattainment problem, as Marginal, 

Moderate, Serious, Severe, or Extreme. In response, EPA 

designated the Southeast Desert Modified Air Quality Maintenance 

Area (AQMA) (“Southeast Desert”) as “Severe-17” nonattainment 

for the 1-hour ozone standard, with an attainment date no later 

than November 15, 2007.2 See 56 FR 56694, November 6, 1991. 

Outside of Indian country, the Los Angeles portion of the 

Southeast Desert lies within the Antelope Valley Air Quality 

Management District (AVAQMD), the San Bernardino County portion 

of the Southeast Desert lies within the Mojave Desert Air 

Quality Management District (MDAQMD), and the Riverside County 

portion of the Southeast Desert lies within the South Coast Air 

Quality Management District (SCAQMD).3

 

2 The Southeast Desert covers the Victor Valley/Barstow region in San 

Bernardino County, the Coachella Valley region in Riverside County, and the 

Antelope Valley portion of Los Angeles County (see 40 CFR 81.305 for the 

precise boundaries of the 1-hour ozone nonattainment area).

3 “Indian country” as defined at 18 U.S.C. 1151 refers to: “(a) all land 

within the limits of any Indian reservation under the jurisdiction of the 

United States Government, notwithstanding the issuance of any patent, and, 

including rights-of-way running through the reservation, (b) all dependent 

Indian communities within the borders of the United States whether within the 

original or subsequently acquired territory thereof, and whether within or 
6

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

The control requirements and date by which attainment of 

the 1-hour ozone standard was to be achieved varied with an 

area’s classification. Marginal areas were subject to the fewest 

mandated control requirements and had the earliest attainment 

date, November 15, 1993, while Severe and Extreme areas were 

subject to more stringent planning requirements and were 

provided more time to attain the standard. Two measures that are 

triggered if a Severe or Extreme area failed to attain the 

standard by the applicable attainment date are contingency 

measures [section 172(c)(9)] and a major stationary source fee 

provision [sections 182(d)(3) and 185](“major source fee 

program” or “section 185 fee program”).

In 1997, EPA promulgated an 8-hour ozone standard (0.08 

ppm) (“1997 8-hour ozone standard”), 62 FR 38856 (July 18, 

1997), to replace the 1-hour ozone standard. While the 1-hour 

ozone standard was revoked in 2005, we continue to determine 

whether areas attain, or fail to attain, the 1-hour ozone 

standard because of the continued applicability of certain 1-

hour ozone control requirements in areas, such as the Southeast 

Desert, that are designated as nonattainment for the 1997 8-hour 

 

without the limits of a state, and (c) all Indian allotments, the Indian 

titles to which have not been extinguished, including rights-of-way running 

through the same.”
7

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

ozone standard and the connection between some of those

requirements and attainment of the 1-hour ozone standard.

In the decades since the 1990 CAA Amendments, in large part 

due to decreases in upwind emissions of ozone precursors, 1-hour 

ozone concentrations in the Southeast Desert have decreased 

substantially. For instance, from 1990 to 2005, the number of 

exceedances of the standard in the Southeast Desert decreased 

from 27 to 4 at the Palm Springs monitor in Coachella Valley and 

from 59 to 3 at the Hesperia monitor in Victor Valley. However, 

despite the improvements, upon review of the ambient data for 

the three years preceding the applicable attainment date (i.e., 

2005-2007), we determined that the Southeast Desert failed to 

attain the 1-hour ozone standard by the 2007 statutory deadline. 

See 76 FR 82133 (December 30, 2011). 

In our proposal to determine that the Southeast Desert had 

failed to attain the standard, we noted that preliminary review 

of data from 2008 through 2010 suggested that the trend toward 

cleaner air in the Southeast Desert was continuing. 76 FR 56694, 

at 56700 (September 14, 2011). Indeed, the trend has continued

with 2010-2012 being the first three-year period in which 

preliminary review of the data suggests that the Southeast 

Desert attained the standard. Given the further improvement in 

ozone conditions in the Southeast Desert, the California Air 
8

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

Resources Board (CARB) has requested that EPA make a 

determination that the Southeast Desert has attained the 1-hour 

ozone standard.4 Year 2013 data is now available, and thus EPA’s 

action herein is based on the most recent three-year period 

(2011-2013).

II. EPA’s analysis

A determination of whether an area’s air quality meets the 

1-hour ozone standard is generally based upon three years of

complete,5 quality-assured and certified air quality monitoring 

data gathered at established State and Local Air Monitoring 

Stations (“SLAMS”) in the nonattainment area and entered into 

EPA's Air Quality System (AQS) database. Data from air monitors 

operated by state/local agencies in compliance with EPA 

monitoring requirements must be submitted to the AQS database. 

Monitoring agencies annually certify that these data are 

accurate to the best of their knowledge. Accordingly, EPA relies 

primarily on data in its AQS database when determining the 

attainment status of an area. See 40 CFR 50.9; 40 CFR part 50, 

appendix H; 40 CFR part 53; 40 CFR part 58, appendices A, C, D 

 

4 See Letter from Richard W. Corey, Executive Officer, CARB, to Jared 

Blumenfeld, Regional Administrator, EPA Region IX, dated February 25, 2014.

5 Generally, a “complete” data set for determining attainment of the ozone is 

one that includes three years of data with an average percent of days with 

valid monitoring data greater than 90% with no single year less than 75%. See 

40 CFR part 50, appendix I. There are less stringent data requirements for 

showing that a monitor has failed an attainment test and thus has recorded a 

violation of the standard.
9

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

and E. All data are reviewed to determine the area's air quality 

status in accordance with 40 CFR part 50, appendix H.

Under EPA regulations at 40 CFR 50.9, the 1-hour ozone 

standard is attained at a monitoring site when the expected 

number of days per calendar year with maximum hourly average 

concentrations above 0.12 ppm is equal to or less than 1.0, as 

determined by 40 CFR part 50, appendix H.6

The CARB is the Primary Quality Assurance Organization 

(PQAO) responsible for assuring that the area meets air quality 

monitoring requirements in the Los Angeles County and San 

Bernardino County portions of the Southeast Desert, and the 

SCAQMD is the PQAO responsible for assuring that the 

requirements are met in the Riverside County portion of the 

Southeast Desert. The AVAQMD operates monitors in the Los 

Angeles County portion of the Southeast Desert; the MDAQMD 

operates monitors in the San Bernardino County portion of the 

Southeast Desert; and the SCAQMD operate monitors in the 

Riverside County portion of the Southeast Desert. All agencies 

are required to submit annual monitoring network plans to EPA. 

The AVAQMD and MDAQMD monitoring networks are included in the 

CARB annual network plan, while SCAQMD submits a separate annual 

 

6 The average number of expected exceedances is determined by averaging the 

expected exceedances of the 1-hour ozone standard over a consecutive three 

calendar year period. See 40 CFR part 50, appendix H.
10

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

network plan. These plans discuss the status of the air 

monitoring network, as required under 40 CFR 58.10.

With respect to the annual network plans submitted by CARB 

that includes the AVAQMD and MDAQMD monitors, we have reviewed 

these plans and found that they meet the applicable requirements 

under 40 CFR part 58.7 The Technical System Audit (TSA) we 

conducted in 2011 of the CARB PQAO included a review of the 

network requirements in AVAQMD and MDAQMD. In the TSA, we 

concluded that the combined ambient air monitoring networks 

operated by CARB and the air districts currently meet or exceed 

the requirements for the minimum number of SLAMS monitoring 

sites for ozone in the Southeast Desert. Also, AVAQMD and MDAQMD 

annually certify that the data submitted to AQS are qualityassured.8

EPA has reviewed SCAQMD’s plans for compliance with the 

applicable requirements in 40 CFR part 58 on an annual basis. 

With respect to ozone, EPA has found that the SCAQMD’s network 

plans meet the applicable requirements under 40 CFR part 58.9

 

7 See, e.g., letter from Meredith Kurpius, Manager, Air Quality Analysis 

Office, EPA Region IX, to Karen Magliano, Air Quality Data Branch, Planning 

and Technical Support Division, CARB, dated May 7, 2014.

8 See, e.g., letters from Christopher A. Collins, Supervising AQ Engineer, 

MDAQMD, to Fletcher Clover, EPA Region IX, dated May 6, 2014, certifying 2013 

data from AVAQMD and MDAQMD.

9 See, e.g., letter from Meredith Kurpius, Manager, Air Quality 

Analysis Office, Air Division, EPA Region IX, to Dr. Matt Miyasato, 

Deputy Executive Officer, Science and Technology Advancement, 

SCAQMD, dated March 11, 2014.
11

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

Furthermore, we concluded in our TSA of the SCAQMD network 

conducted during April 2010, that the ambient air monitoring 

network operated by SCAQMD currently meets or exceeds the 

requirements for the minimum number of SLAMS monitoring sites 

for all criteria pollutants, and the ozone monitoring sites 

within the Southeast Desert are properly located with respect to 

monitoring objectives, spatial scales and other site criteria, 

as required by 40 CFR part 58, appendix D.10 Also, SCAQMD 

annually certifies that the data it submits to AQS are qualityassured.11

There were eight ozone monitoring sites located throughout 

the Southeast Desert in calendar years 2011 through 2013 that 

collected data for regulatory purposes: one in Los Angeles 

County, two in Riverside County, and five in San Bernardino 

County.12 All of the sites monitor ozone concentrations on a 

continuous basis using Federal Equivalent Method (FEM) monitors. 

AVAQMD operates the one monitor in Los Angeles County. SCAQMD 

 

10 See letter from Deborah Jordan, Director, Air Division, 

U.S. EPA Region IX, to Barry Wallerstein, Executive Officer, SCAQMD, 

dated March 14, 2011, and enclosure titled, “Technical System Audit 

Report, South Coast Air Quality Management District, April 13-April 

16, 2010.”

11 See, e.g., letter from Matt Miyasoto, Deputy Executive 

Office, Science and Technology Advancement, SCAQMD, to Jared 

Blumenfeld, Regional Administrator, EPA Region IX, dated June 27, 2014, 

certifying 2013 ozone data.

12 See figures 5 and 11 from CARB’s State and Local Air Monitoring Network 

Plan (June 2009) for illustrations of the locations of the ozone monitors 

within the Southeast Desert.
12

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

operates two in Riverside County. MDAQMD operates four in San 

Bernardino County. The National Park Service operates one 

monitor in San Bernardino County at Joshua Tree National Park 

(Yucca Valley).13 Also, the National Park Service annually 

certifies that the data it submits to AQS are quality-assured.14

Table 1 summarizes the ozone monitoring data from the 

various monitoring sites in the Southeast Desert, showing the 

expected exceedances per year and as an average over the 2011-

2013 period. The data summarized in table 1 are considered 

complete for the purposes of determining if the standard is 

met.15

Table 1 – One-Hour Ozone Data for the Southeast Desert 1-Hour 

Ozone Nonattainment Area

General Location Site (AQS ID)

Expected 

Exceedances by 

Year

Expected 

Exceedances 

3-year

average

2011 2012 2013 2011-2013

Antelope Valley / 

Los Angeles County

Lancaster

(06-037-9033)

0.0 0.0 0.0 0.0

Coachella Valley / 

Riverside County

Indio

(06-065-2002)

0.0 0.0 0.0 0.0

Coachella Valley / Palm Springs 0.0 1.0 0.0 0.3

 

13 The National Park Service also operates an ozone monitor in Riverside 

County at Joshua Tree National Park (Cottonwood Visitor Center; AQS ID 06-

065-0008), but until recently, the monitor has not been either a federal 

reference method or federal equivalent method monitor. Thus, we are not using 

the data from this Cottonwood monitor for the proposed determination of 

attainment. 

14 See, e.g., letter from Kristi Morris, Program Manager, National Park 

Service, to Lew Weinstock, EPA, dated April 29, 2014, certifying 2013 ozone 

data.

15 The criteria for data completeness are met at all of the ozone monitors in 

the Southeast Desert over the 2011-2013 period.
13

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

Riverside County (06-065-5001)

Northern portion 

of SE Desert AQMA 

/ San Bernardino 

County

Barstow

(06-071-0001)

0.0 0.0 0.0 0.0

SW portion of SE 

Desert AQMA / San 

Bernardino County

Hesperia

(06-071-4001)

1.0 0.0 0.0 0.3

SW portion of SE 

Desert AQMA / San 

Bernardino County

Phelan

(06-071-0012)

0.0 0.0 0.0 0.0

SW portion of SE 

Desert AQMA / San 

Bernardino County

Victorville

(06-071-0306)

0.0 0.0 0.0 0.0

Joshua Tree 

National Park / 

San Bernardino 

County

Yucca Valley

(06-071-9002)

0.0 0.0 0.0 0.0

Source: AQS Quick Look Report, May 9, 2014 (in the docket to 

this proposed action).

Generally, the highest ozone concentrations in the 

Southeast Desert occur in the far southwestern portion of the 

area, near mountain passes through which pollutants are 

transported to the Southeast Desert from the South Coast Air 

Basin. As shown in table 1, the highest three-year average of 

expected exceedances at any site in the Southeast Desert for 

2011-2013 is 0.3 at Palm Springs in Riverside County and 

Hesperia in San Bernardino County. The calculated exceedance 

rate of 0.3 represents attainment of the 1-hour ozone standard 

(a three-year average of expected exceedances less than or equal 

to 1).
14

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

Taking into account the extent and reliability of the 

applicable ozone monitoring network, and the data collected 

therefrom and summarized in table 1, we propose to determine 

that the Southeast Desert has attained the 1-hour ozone standard 

(as defined in 40 CFR part 50, appendix H) based on the most 

recent three years of monitoring data for the area (2011-2013).

Data for 2014 will be reviewed prior to our final action to 

ensure that it is consistent with continued attainment of the 1-

hour ozone standard in the Southeast Desert.

III. Proposed EPA Action and Request for Public Comment

EPA is proposing to determine that the Southeast Desert 

Area has attained the 1-hour ozone standard based on complete, 

quality-assured and certified ambient air quality monitoring 

data for the 2011-2013 monitoring period.

EPA is soliciting public comments on the issues discussed 

in this document or on other relevant matters. We will accept 

comments from the public on this proposal for the next 30 days. 

We will consider these comments before taking final action.

IV. Statutory and Executive Order Reviews

This action proposes to make a determination based on air 

quality data and does not impose additional requirements beyond 

those imposed by state law. For that reason, this proposed 

action:
15

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

 Is not a “significant regulatory action” subject to review 

by the Office of Management and Budget under Executive 

Order 12866 (58 FR 51735, October 4, 1993);

 Does not impose an information collection burden under the 

provisions of the Paperwork Reduction Act (44 U.S.C. 3501 

et seq.);

 Is certified as not having a significant economic impact on 

a substantial number of small entities under the Regulatory 

Flexibility Act (5 U.S.C. 601 et seq.);

 Does not contain any unfunded mandate or significantly or 

uniquely affect small governments, as described in the 

Unfunded Mandates Reform Act of 1995 (Pub. L. 104–4);

 Does not have Federalism implications as specified in 

Executive Order 13132 (64 FR 43255, August 10, 1999); is 

not an economically significant regulatory action based on 

health or safety risks subject to Executive Order 13045 (62 

FR 19885, April 23, 1997); 

 Is not a significant regulatory action subject to Executive 

Order 13211 (66 FR 28355, May 22, 2001);

 Is not subject to requirements of section 12(d) of the 

National Technology Transfer and Advancement Act of 1995 

(15 U.S.C. 272 note) because application of those 

requirements would be inconsistent with the CAA; and,
16

This document is a prepublication version, signed by Alexis Straus, Acting Regional Administrator, EPA Region 9 

on August 12, 2014. We have taken steps to ensure the accuracy of this version, but it is not the official version.

 Does not provide EPA with the discretionary authority to 

address, as appropriate, disproportionate human health or 

environmental effects, using practicable and legally 

permissible methods, under Executive Order 12898 (59 FR 

7629, February 16, 1994). 

In addition, this rule does not have tribal implications as 

specified by Executive Order 13175 (65 FR 67249, November 9, 

2000), because it will not impose substantial direct costs on 

tribal governments or preempt tribal law.

List of Subjects in 40 CFR Part 52

Environmental protection, Air pollution control,

Intergovernmental relations, Oxides of nitrogen, Ozone, Volatile 

organic compounds.

 

__________________ ________________________

Dated: Jared Blumenfeld,

Regional Administrator,

Region IX