
[Federal Register: November 2, 2010 (Volume 75, Number 211)]
[Rules and Regulations]               
[Page 67220-67227]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr02no10-5]                         

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 81

[EPA-R09-OAR-2010-0718; FRL-9219-7]

 
Determinations of Attainment by the Applicable Attainment Date 
for the Hayden, Nogales, Paul Spur/Douglas PM10 
Nonattainment Areas, Arizona

AGENCY: Environmental Protection Agency (EPA).

ACTION: Direct final rule.

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SUMMARY: EPA has determined that the Hayden, Nogales, and Paul Spur/
Douglas nonattainment areas in Arizona attained the National Ambient 
Air Quality Standard (NAAQS) for particulate matter with an aerodynamic 
diameter of less than or equal to a nominal ten micrometers 
(PM10) by the applicable attainment date of December 31, 
1994. On the basis of this determination, EPA concludes that these 
three ``moderate'' nonattainment areas are not subject to 
reclassification by operation of law to ``serious.'' Lastly, on the 
basis of a review of more recent ambient monitoring data, EPA has 
determined that the Hayden, Nogales, and Paul Spur/Douglas 
nonattainment areas are not currently attaining the PM10 
standard.

DATES: This action is effective on January 3, 2011 without further 
notice, unless EPA receives adverse comment by December 2, 2010. If EPA 
receives adverse comment, we will publish a timely withdrawal in the 
Federal Register informing the public that the rule will not take 
effect.

ADDRESSES: Submit comments, identified by docket number EPA-R09-OAR-
2010-0718, by one of the following methods:
    1. Federal eRulemaking Portal: http://www.regulations.gov. Follow 
the on-line instructions.
    2. E-mail: tax.wienke@epa.gov.
    3. Mail or deliver: Wienke Tax, Air Planning Office, EPA Region IX, 
75 Hawthorne Street, San Francisco, CA 94105-3901.
    Instructions: All comments will be included in the public docket 
without change and may be made available online at http://
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 http://
www.regulations.gov or e-mail. http://www.regulations.gov 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 an e-mail directly to EPA, your e-mail address will be 
automatically captured and included as part of the public comment. If 
you submit an electronic comment, EPA recommends that you include your 
name and other contact information in the body of your comment and with 
any disk or CD-ROM you submit. If EPA cannot read your comment due to 
technical difficulties and cannot contact you for clarification, EPA 
may not be able to consider your comment. Electronic files should avoid 
the use of special characters, any form of encryption, and be free of 
any defects or viruses.
    Docket: The index to the docket for this action is available 
electronically at http://www.regulations.gov and in hard copy at EPA 
Region IX, 75 Hawthorne Street, San Francisco, California. While all 
documents in the docket are listed in the index, some information may 
be publicly available only at the hard copy location (e.g., copyrighted 
material), and some may not be publicly available in 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.

FOR FURTHER INFORMATION CONTACT: Wienke Tax at telephone number: (415) 
947-4192; e-mail address: tax.wienke@epa.gov, or the above EPA, Region 
IX address.

SUPPLEMENTARY INFORMATION: Throughout this document, wherever ``we'', 
``us'' or ``our'' are used, we mean EPA. Information is organized as 
follows:

[[Page 67221]]

Table of Contents

I. Background
A. PM10 NAAQS
B. Designation and Classification of PM10 Nonattainment 
Areas
C. How does EPA make attainment determinations?
D. What PM10 planning has occurred for the Hayden, 
Nogales, and Paul Spur/Douglas PM10 Nonattainment Areas?
1. Hayden PM10 Nonattainment Area
2. Nogales PM10 Nonattainment Area
3. Paul Spur/Douglas PM10 Nonattainment Area
II. EPA's Analysis
A. What does the air quality data show as of the December 31, 1994 
attainment date?
1. Hayden PM10 Nonattainment Area
2. Nogales PM10 Nonattainment Area
3. Paul Spur/Douglas PM10 Nonattainment Area
B. Does more recent air quality data also show attainment?
1. Hayden PM10 Nonattainment Area
2. Nogales PM10 Nonattainment Area
3. Paul Spur/Douglas PM10 Nonattainment Area
III. EPA's Final Action
IV. Statutory and Executive Order Reviews

I. Background

A. PM10 NAAQS

    The NAAQS are levels for certain ambient air pollutants set by EPA 
to protect public health and welfare. PM10, or particulate 
matter with an aerodynamic diameter less than or equal to a nominal 10 
micrometers, is among the ambient air pollutants for which EPA has 
established health-based standards. On July 1, 1987 (52 FR 24634), EPA 
promulgated two primary standards for PM10: A 24-hour 
standard of 150 micrograms per cubic meter ([micro]g/m\3\) and an 
annual PM10 standard of 50 [micro]g/m\3\. EPA also 
promulgated secondary PM10 standards that were identical to 
the primary standards.
    Effective December 18, 2006, EPA revoked the annual PM10 
standard but retained the 24-hour PM10 standard. 71 FR 61144 
(October 17, 2006). The 24-hour PM10 standard is attained 
when the expected number of days per calendar year with a 24-hour 
concentration in excess of the standard (referred to herein as 
``exceedance''), as determined in accordance with 40 CFR part 50, 
appendix K, is equal to or less than one.\1\ See 40 CFR 50.6 and 40 CFR 
part 50, appendix K.
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    \1\ An exceedance is defined as a daily value that is above the 
level of the 24-hour standard (150 [micro]g/m\3\) after rounding to 
the nearest 10 [micro]g/m\3\ (i.e., values ending in 5 or greater 
are to be rounded up). Thus, a recorded value of 154 [micro]g/m\3\ 
would not be an exceedance since it would be rounded to 150 
[micro]g/m\3\ whereas a recorded value of 155 [micro]g/m\3\ would be 
an exceedance since it would be rounded to 160 [micro]g/m\3\. See 40 
CFR part 50, appendix K, section 1.0.
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B. Designation and Classification of PM10 Nonattainment 
Areas

    Areas meeting the requirements of section 107(d)(4)(B) of the Clean 
Air Act (CAA or ``Act'') were designated nonattainment for 
PM10 by operation of law and classified ``moderate'' upon 
enactment of the 1990 Clean Air Act Amendments. These areas included 
all former Group I PM10 planning areas identified in 52 FR 
29383 (August 7, 1987), as further clarified in 55 FR 45799 (October 
31, 1990), and any other areas violating the NAAQS for PM10 
prior to January 1, 1989. A Federal Register notice announcing the 
areas designated nonattainment for PM10 upon enactment of 
the 1990 Amendments, known as ``initial'' PM10 nonattainment 
areas, was published on March 15, 1991 (56 FR 11101) and a subsequent 
Federal Register document correcting the description of some of these 
areas was published on August 8, 1991 (56 FR 37654).
    As former ``group I'' areas, the Hayden/Miami \2\ and Paul Spur/
Douglas \3\ areas were included in the list of initial moderate 
PM10 nonattainment areas. Nogales, a former ``Group II'' 
area, was included in the initial list of moderate PM10 
nonattainment areas based on monitored violations of the 
PM10 NAAQS prior to January 1, 1989.\4\ Later in 1991, we 
codified the PM10 nonattainment designations and moderate 
area classifications in 40 CFR part 81. See 56 FR 56694 (November 6, 
1991). For ``moderate'' nonattainment areas such as the three Arizona 
areas that are the subject of this document, CAA section 188(c) of the 
1990 Amended Act establishes an attainment date of December 31, 1994. 
The designations, classifications, and boundaries of these three 
Arizona nonattainment areas are codified at 40 CFR 81.303.
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    \2\ On March 28, 2007, EPA approved a request by the State of 
Arizona to split the Hayden/Miami PM10 nonattainment area 
into two separate PM10 nonattainment areas. See 72 FR 
14422 (March 28, 2007). In our March 28, 2007 direct final rule, we 
also determined that the Miami PM10 nonattainment area 
had attained the PM10 NAAQS. In today's action, we have 
determined that the Hayden PM10 nonattainment area 
attained the PM10 NAAQS by the applicable attainment 
date. The Hayden planning area straddles Gila and Pinal counties at 
the confluence of the Gila and San Pedro rivers in east central 
Arizona. The nonattainment area covers roughly 700 miles of 
mountainous terrain. Cities and towns within this area include 
Kearney (population roughly 2,800), Hayden (population roughly 800), 
and Winkelman (population roughly 400).
    \3\ The Paul Spur/Douglas planning area covers approximately 220 
square miles along the border with Mexico within Cochise County. 
Cities and towns within this area include Douglas (population 
roughly 20,000) and Pirtleville (population roughly 1,500). The 
population of Agua Prieta, Mexico, which lies just across the border 
from Douglas is roughly 70,000.
    \4\ The Nogales planning area covers approximately 70 square 
miles along the border with Mexico within Santa Cruz County. The 
only significant population center in this area is the city of 
Nogales with a population of roughly 21,000. The population of 
Nogales, Mexico, which lies just across the border from Nogales, 
Arizona is roughly 160,000.
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C. How does EPA make attainment determinations?

    Section 188(b)(2) of the Act requires EPA to determine within six 
months of the applicable attainment date whether, based on air quality 
data, PM10 nonattainment areas attained the PM10 
NAAQS by that date. Generally, EPA determines whether an area's air 
quality is meeting the PM10 NAAQS based upon complete 
(minimum of 75 percent of scheduled PM10 samples recorded), 
quality-assured data gathered at established state and local air 
monitoring stations (SLAMS) and national air monitoring stations (NAMS) 
in the nonattainment area and entered into the EPA Air Quality System 
(AQS) database. Data from air monitors operated by State/local/tribal 
agencies in compliance with EPA monitoring requirements must be 
submitted to AQS. EPA relies primarily on data in AQS when determining 
the attainment status of an area. See 40 CFR 50.6; 40 CFR part 50, 
appendix J; 40 CFR part 53; 40 CFR part 58, appendix A. EPA will also 
consider air quality data from other air monitoring stations in the 
nonattainment area provided that the stations meet the Federal 
monitoring requirements for SLAMS, including the quality assurance and 
quality control criteria in 40 CFR part 58, appendix A. 40 CFR 58.14 
(2006) and 58.20 (2007); \5\ 71 FR 61236, 61242 (October 17, 2006). All 
valid data are reviewed to determine the area's air quality status in 
accordance with 40 CFR part 50, appendix K.
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    \5\ EPA promulgated amendments to the ambient air monitoring 
regulations in 40 CFR parts 53 and 58 on October 17, 2006. See 71 FR 
61236. The requirements for Special Purpose Monitors were revised 
and moved from 40 CFR 58.14 to 40 CFR 58.20.
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    Attainment of the 24-hour PM10 standard is determined by 
calculating the expected number of exceedances of the standard in a 
year. The 24-hour PM10 standard is attained when the 
expected number of exceedances averaged over a three-year period is 
less than or equal to one at each monitoring site within the 
nonattainment area. Generally, three consecutive years of air quality 
data are required to show attainment of the 24-hour PM10

[[Page 67222]]

standard. See 40 CFR part 50 and appendix K.\6\
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    \6\ Because the annual PM10 standard was revoked 
effective December 18, 2006, see 71 FR 61144 (October 17, 2006), 
this document discusses only attainment of the 24-hour 
PM10 standard.
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    To demonstrate attainment of the 24-hour PM10 standard 
at a monitoring site, the monitor must provide sufficient data to 
perform the required calculations in 40 CFR part 50, appendix K. The 
amount of data required varies with the sampling frequency, data 
capture rate and the number of years of record. In all cases, three 
years of representative monitoring data that meet the 75 percent 
criterion of the previous paragraph should be utilized, if available, 
and would suffice. More than three years may be considered, if all 
additional representative years of data meeting the 75 percent 
criterion are utilized. Data not meeting these criteria may also 
suffice to show attainment; however, such exceptions must be approved 
by the appropriate Regional Administrator in accordance with EPA 
guidance. See 40 CFR part 50, appendix K, section 2.3.

D. What PM10 planning has occurred for the Hayden, Nogales, and Paul 
Spur/Douglas PM10 Nonattainment Areas?

    Along with the new designations, classifications, and attainment 
dates, the CAA as amended in 1990 also established new planning 
requirements. All initial moderate PM10 nonattainment areas 
had the same applicable attainment date of December 31, 1994. States 
containing initial moderate PM10 nonattainment areas were 
required to develop and submit to EPA by November 15, 1991, a state 
implementation plan (SIP) revision providing for implementation of 
reasonably available control measures (RACM) for the control of 
PM10, and either a demonstration that the plan would provide 
for attainment by the applicable attainment date (December 31, 1994) or 
a demonstration that attainment by such date was impracticable. See CAA 
section 189(a).
1. Hayden PM10 Nonattainment Area
    By November 15, 1991, States were required to submit SIP revisions 
addressing certain CAA requirements for initial PM10 
nonattainment areas. The State of Arizona relied upon a SIP revision 
(``Final PM10 State Implementation Plan for the Hayden Group 
I Area,'' September 1989) (herein referred to as the ``1989 Hayden 
PM10 Plan'') that it had submitted on October 16, 1989 to 
meet the requirements of the CAA as amended in 1990 for the Hayden/
Miami moderate PM10 nonattainment area. See letter from 
Edward Z. Fox, Director, Arizona Department of Environmental Quality 
(ADEQ), to Daniel W. McGovern, Regional Administrator, EPA Region IX, 
dated February 3, 1992. The inventory in the 1989 Hayden 
PM10 Plan identifies the ASARCO copper smelter and related 
sources, such as the smelter stack, copper ore tailings, ore crushing, 
the slag dump, road dust, smelter building fugitives, and copper ore, 
as the principal sources of PM10 emissions in the Hayden 
portion of the Hayden/Miami PM10 nonattainment area.
    In 1994, we proposed a limited approval and limited disapproval of 
the 1989 Hayden PM10 Plan. See 59 FR 36116 (July 15, 1994). 
In our 1994 proposed action, we identified deficiencies in the 1989 
Hayden PM10 Plan including the failure of the plan to 
address the Miami portion of the Hayden/Miami PM10 
nonattainment area and the failure to meet the general monitoring 
requirements for the entire nonattainment area. (As noted above in 
footnote 2, we have since approved ADEQ's request to split the Hayden 
and Miami portions of the area into separate PM10 
nonattainment areas.) We have not finalized our 1994 proposed limited 
approval/limited disapproval or otherwise taken action on the 1989 
Hayden PM10 Plan.
2. Nogales PM10 Nonattainment Area
    Arizona did not submit the required moderate PM10 plan 
by the November 15, 1991 deadline for the Nogales nonattainment area, 
and on December 16, 1991, we made a finding of failure to submit the 
moderate PM10 plan for Nogales. See letter from Daniel W. 
McGovern, Regional Administrator, EPA Region IX, to Fife Symington, 
Governor of Arizona, dated December 16, 1991. See 57 FR 19906 (May 8, 
1992). In response, on June 14, 1993, ADEQ submitted the ``Final State 
Implementation Plan for the Nogales PM10 Nonattainment 
Area,'' June 1993 (herein referred to as the ``1993 Nogales 
PM10 Plan''), to EPA as a SIP revision. We found the plan to 
be complete and notified the State of our finding by letter dated 
November 30, 1993.
    The 1993 Nogales PM10 Plan identifies emissions sources 
located in Mexico as the principal sources affecting ambient 
PM10 concentrations in the area, and includes an analysis 
which concludes that the plan would be adequate to attain the 
PM10 NAAQS but for emissions emanating from outside the 
United States. Section 179B (``International Border Areas'') of the CAA 
provides EPA with the authority to approve such a demonstration. We 
have not taken action to approve or disapprove the 1993 Nogales 
PM10 Plan.
3. Paul Spur/Douglas PM10 Nonattainment Area
    Similar to the situation in Hayden, the State of Arizona relied 
upon a SIP revision (``Final PM10 State Implementation Plan 
for the Paul Spur Group I Area,'' July 1990) (herein referred to as the 
``1990 Paul Spur PM10 Plan'') that it had submitted prior to 
the CAA Amendments of 1990 (in this instance, June 25, 1990) to meet 
the requirements of the CAA as amended in 1990 for the Paul Spur 
portion of the Paul Spur/Douglas moderate PM10 nonattainment 
area. See letter from Edward Z. Fox, Director, ADEQ, to Daniel W. 
McGovern, Regional Administrator, EPA Region IX, dated February 3, 
1992. The 1990 Paul Spur PM10 Plan identifies the lime plant 
located at Paul Spur as the only significant source of emissions in the 
immediate vicinity and includes control measures for this source of 
emissions.
    ADEQ did not submit the required plan for the Douglas portion of 
the Paul Spur/Douglas nonattainment area by the November 15, 1991 
deadline, and thus, on December 16, 1991, we made a finding of failure 
to submit a moderate PM10 plan for Douglas portion of Paul 
Spur/Douglas PM10 nonattainment area. See letter from Daniel 
W. McGovern, Regional Administrator, EPA Region IX, to Fife Symington, 
Governor of Arizona, dated December 16, 1991. See 57 FR 19906 (May 8, 
1992). In response, on June 17, 1993, ADEQ submitted the ``Final State 
Implementation Plan for the Douglas PM10 Nonattainment 
Area,'' April 1993 (herein referred to as the ``1993 Douglas 
PM10 Plan''), to EPA as a SIP revision. We found the plan to 
be complete by letter dated November 30, 1993. Similar to the Nogales 
plan, the 1993 Douglas PM10 plan identifies emissions 
sources located in Mexico as the principal sources of emissions 
affecting ambient PM10 concentrations in the area, and 
includes an analysis which concludes that the plan would be adequate to 
attain the PM10 NAAQS but for emissions emanating from 
outside the United States.
    A decade later, and based on a number of years of ambient data 
showing that the standard had been attained, ADEQ withdrew the 1993 
Douglas PM10 Plan. See letter from Stephen A. Owens, 
Director, ADEQ, to Wayne Nastri, Regional Administrator, EPA Region IX, 
dated December 22, 2004. Recently, ADEQ revoked the 2004 withdrawal of 
the 1993 Douglas PM10 Plan; thus, once again, the plan is 
subject to EPA approval or disapproval

[[Page 67223]]

action as a revision to the Arizona SIP. See letter from Benjamin H. 
Grumbles, Director, ADEQ, to Jared Blumenfeld, Regional Administrator, 
EPA Region IX, dated September 13, 2010. We have not taken action to 
approve or disapprove either the 1990 Paul Spur PM10 Plan or 
the 1993 Douglas PM10 Plan.

II. EPA's Analysis

A. What does the air quality data show as of the December 31, 1994 
attainment date?

    ADEQ is responsible for monitoring ambient air quality outside the 
metropolitan areas in Arizona. ADEQ submits monitoring network plan 
reports to EPA on an annual basis. These reports discuss the status of 
the air monitoring network, as required under 40 CFR part 58. Beginning 
in 2007, EPA reviews these annual plans for compliance with the 
applicable reporting requirements in 40 CFR 58.10. With respect to 
PM10, we have found that ADEQ's annual network plans meet 
the applicable requirements under 40 CFR part 58. See EPA letters to 
ADEQ concerning ADEQ's annual network plan reports for years 2007, 
2008, and 2009 that have been placed in the docket for this rulemaking. 
Furthermore, we concluded in our Technical System Audit Report 
(September 2010) for ADEQ's ambient air quality monitoring program (a 
copy of which has been placed in the docket) that ADEQ's ambient air 
monitoring network currently meets or exceeds the requirements for the 
minimum number of monitoring sites designated as SLAMS for all of the 
criteria pollutants, and that all of the monitoring sites are properly 
located with respect to monitoring objectives, spatial scales and other 
siting criteria.
1. Hayden PM10 Nonattainment Area
    ADEQ has operated a PM10 monitor at the Old Town Jail 
site, which is near the center of the Town of Hayden, for many years, 
including the period 1992 through 1994. The Old Town Jail monitoring 
site is part of the ADEQ's SLAMS network and is located roughly one-
half mile west of the ASARCO smelter. During the 1992-1994 period, ADEQ 
used a filter-based method (low-volume dichotomous monitor) to monitor 
ambient PM10 concentrations, sampling PM10 
concentrations every sixth day. The Old Town Jail monitor was sited to 
provide PM10 concentration data at a neighborhood scale \7\ 
for the purpose of determining source impacts from ASARCO operations. 
Table 1 below summarizes the PM10 concentration data 
collected at the Old Town Jail site over the 1992-1994 period.
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    \7\ In this context, ``neighborhood scale'' refers to conditions 
throughout some reasonably homogeneous urban sub-region with 
dimensions of a few kilometers. See 40 CFR part 58, appendix D, 
section 4.6.

                Table 1--Summary of PM10 Monitoring Data, Hayden Nonattainment Area, 1992-1994 a
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                                                            Highest 24-hour PM10  concentration      Expected
                                                                         ([mu]g/m3)                 exceedances
                     Monitoring site                      ---------------------------------------    per year
                                                                                                 ---------------
                                                               1992         1993         1994        1992-1994
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Hayden Old Jail..........................................           85           68           67             0.0
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PM10 NAAQS = 150 [mu]g/m3.
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\a\ Source: AQS QuickLook report dated June 23, 2010.

    As noted above, to be considered ``complete,'' valid measurements 
must be made for 75% of all the scheduled sampling dates in each 
quarter of the year, and generally, three years of representative 
monitoring data that meet the 75 percent criterion should be utilized, 
where available.
    During the 1992-1994 period, the data collected by ADEQ meets the 
completeness criterion for all quarters except for the fourth quarter 
of year 1994, when the number of valid samples was one short of 
constituting a complete quarter. EPA may find that data not meeting the 
completeness criterion suffice to show attainment. See 40 CFR part 50, 
appendix K, section 2.3(b). Relevant considerations that we take into 
account when evaluating whether data not meeting the completeness 
criterion would suffice include, but are not limited to, monitoring 
site closures/moves, monitoring diligence, consistency and levels of 
the valid concentration measurements that are available, and nearby 
concentrations. See, e.g., considerations taken into account for 
analogous circumstances involving evaluating of ambient lead (Pb) 
concentrations at 40 CFR part 50, appendix F, section 4(d).
    In this instance, we find that data that is available is sufficient 
to determine whether the area attained the standard by the applicable 
attainment date. First, we note the large extent to which the maximum 
monitored levels during the 1992-1994 period (67 to 85 [micro]g/m\3\--
see table 1 above) fall below the applicable standard (150 [micro]g/
m\3\). We also note that 11 of the 12 quarters in question were 
complete (based on the 75% criterion), and that the one quarter that 
did not meet the criterion was but one sample short. Further, we have 
reviewed the monitoring data for year 1995, which is comprised of four 
quarters of data meeting the completeness criterion, and during which 
the maximum 24-hour concentration was, at 108 [mu]g/m\3\, well below 
the standard, providing further evidence that the area attained by the 
applicable attainment date.
    Based on our rationale presented above, we find the available data 
sufficient to determine whether the Hayden nonattainment area met the 
PM10 standard by December 31, 1994 (i.e., the applicable 
attainment date), and based on our review of the air quality data 
during the three-year period ending with the December 31, 1994 
attainment date (and summarized above in table 1), we find that the 
expected number of exceedances per year for the Hayden PM10 
nonattainment area for 1992 to 1994 was 0 days per year. With less than 
an annual expected exceedance rate for the 24-hour PM10 
NAAQS of 1.0, these data represent attainment of the standard. 
Therefore, EPA has determined that the Hayden PM10 
nonattainment area attained the PM10 NAAQS by the applicable 
attainment date.
2. Nogales PM10 Nonattainment Area
    ADEQ has operated a PM10 monitor at the Nogales Post 
Office site (300 North Morley Avenue) for many years, including the 
period 1992 through 1994. The Nogales Post Office monitoring site is 
part of the ADEQ's SLAMS network

[[Page 67224]]

and is located roughly 0.4 mile north of the border with Mexico. During 
year 1994, ADEQ also collected a total of 120 samples of 24-hour-
average ambient PM10 concentrations at three additional 
locations in Nogales, all of which were located north of the Post 
Office Site.
    During the 1992-1994 period, ADEQ used a filter-based method (low-
volume dichotomous monitor) to monitor ambient PM10 
concentrations in the Nogales area. At the Nogales Post Office site, 
the sampling schedule was every sixth day. The Nogales Post Office 
monitor was sited to provide PM10 concentration data at a 
neighborhood scale for the purpose of determining population exposure. 
Table 2 below summarizes the PM10 concentration data 
collected in the Nogales area over the 1992-1994 period.

                Table 2--Summary of PM10 Monitoring Data, Nogales Nonattainment Area, 1992-1994a
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                                                          Highest 24-         Expected exceedances per year
                                                           hour PM10   -----------------------------------------
                    Monitoring site                      concentration
                                                          ([mu]g/m\3\)     1992       1993         1992-1994
----------------------------------------------------------------------------------------------------------------
Nogales Post Office....................................          153          119        116                 0.0
885 North Carrillo Place...............................  .............  .........         52  ..................
156 West Mariposa Road.................................  .............  .........         59  ..................
1852 North Mastick Way.................................  .............  .........         83  ..................
----------------------------------------------------------------------------------------------------------------
PM10 NAAQS = 150 [mu]g/m\3\. The 153 [mu]g/m\3\ concentration measured in 1992 does not represent an exceedance
 due to rounding conventions. See footnote 1 of this document for a description of the rounding conventions.
 Measurements at the North Carrillo, West Mariposa, and North Mastick sites were not collected in 1992 or 1993.
----------------------------------------------------------------------------------------------------------------
\a\ Source: AQS QuickLook report dated June 23, 2010.

    As noted above, to be considered ``complete,'' valid measurements 
must be made for 75% of all the scheduled sampling dates in each 
quarter of the year, and generally, three years of representative 
monitoring data that meet the 75 percent criterion should be utilized, 
where available.
    During the 1992-1994 period, 150 samples were collected at the 
Nogales Post Office site out of a total of 183 scheduled sample days. 
However, on a quarter-by-quarter basis, a number of quarters (one in 
1992, three in 1993, and 1 in 1994) failed to meet the 75% completeness 
criterion. For three of the quarters that failed to meet the 75% 
criterion, the criterion was missed by a single sample day, and for the 
two other quarters that failed to meet the 75% criterion, the criterion 
was missed by two sample days. In summary, a substantial amount of data 
was collected during the quarters that failed to meet the 75% 
criterion, but not enough to meet the test. As noted above for the 
Hayden area, EPA may find that data not meeting the completeness 
criterion suffice to show attainment. See 40 CFR part 50, appendix K, 
section 2.3(b).
    Like Hayden, again, we find that data is available and sufficient 
to determine whether the Nogales area attained the standard by the 
applicable attainment date. First, despite a number of quarters that 
did not meet the 75% criterion, we note that a substantial amount of 
data was collected; and, other than two samples taken in year 1992 (1st 
high of 153 [mu]g/m\3\ and 2nd high of 147 [mu]g/m\3\), the ambient 
concentrations that were collected were consistently well below the 150 
[mu]g/m\3\ standard. Second, we take note of the supplemental ambient 
PM10 monitoring data collected by ADEQ during 1994 showing 
ambient concentrations at sites north of the Post Office site well 
below the 150 [mu]g/m\3\ standard (the maximum was 83 [mu]g/m\3\--see 
table 2, above). Lastly, we have reviewed the monitoring data for year 
1995, which is comprised of 53 samples out of a total number of 
scheduled sample days of 61, and during which the maximum 24-hour 
concentration was, at 123 [mu]g/m\3\, well below the standard, 
providing further evidence that the area attained by the applicable 
attainment date.
    Based on our rationale presented above, we find the available data 
sufficient to determine whether the Nogales nonattainment area met the 
PM10 standard by December 31, 1994 (i.e., the applicable 
attainment date), and based on our review of the air quality data 
during the three-year period ending with the December 31, 1994 
attainment date (and summarized above in table 2), we find that the 
expected number of exceedances per year for the Nogales PM10 
nonattainment area for 1992 to 1994 was 0 days per year. With less than 
an annual expected exceedance rate for the 24-hour PM10 
NAAQS of 1.0, these data represent attainment of the standard. 
Therefore, EPA has determined that the Nogales PM10 
nonattainment area attained the PM10 NAAQS by the applicable 
attainment date.
3. Paul Spur/Douglas PM10 Nonattainment Area
    ADEQ has operated PM10 monitors near the lime plant at 
Paul Spur (``Paul Spur monitor'') and within the City of Douglas 
(``Douglas monitor'') for many years, including the period 1992 through 
1994. Both sites are part of the ADEQ's SLAMS network. The Paul Spur 
monitor is located near the intersection of Paul Spur Road and State 
Route 80. During the 1992-1994 period, the Douglas monitor was located 
at 15th Street Park, approximately one mile north of the border with 
Mexico. In 1998, ADEQ re-located the Douglas monitor to its current 
location, the Red Cross building just across from the park on 15th 
Street.
    During the 1992-1994 period, ADEQ used a filter-based method (low-
volume dichotomous monitor) to monitor ambient PM10 
concentrations at both the Paul Spur and Douglas sites, sampling 
PM10 concentrations every sixth day. The Paul Spur monitor 
was sited to provide PM10 concentration data at a middle 
scale \8\ for the purpose of determining source impacts from the 
chemical lime plant. The Douglas monitor was sited to provide 
PM10 concentration data at a neighborhood scale for the 
purpose of determining population exposure. Table 3 below summarizes 
the PM10 concentration data collected at the Paul Spur and 
Douglas monitors over the 1992-1994 period.
---------------------------------------------------------------------------

    \8\ In this context, ``middle scale'' refers to conditions 
characteristic of areas from 100 meters to several kilometers. See 
40 CFR part 58, appendix D, section 4.6.

[[Page 67225]]



           Table 3--Summary of PM10 Monitoring Data, Paul Spur/Douglas Nonattainment Area, 1992-1994 a
----------------------------------------------------------------------------------------------------------------
                                                             Highest 24-hour PM10 concentration      Expected
                                                                         ([mu]g/m3)                 exceedances
                     Monitoring site                      ---------------------------------------    per year
                                                                                                 ---------------
                                                               1992         1993         1994        1992-1994
----------------------------------------------------------------------------------------------------------------
Paul Spur Chemical Lime Plant............................          132           69           77             0.0
Douglas (15th Street Park)...............................          138           66           96             0.0
----------------------------------------------------------------------------------------------------------------
PM10 NAAQS = 150 [mu]g/m\3\.
----------------------------------------------------------------------------------------------------------------
\a\ Source: AQS QuickLook report dated June 23, 2010.

    As noted above, to be considered ``complete,'' valid measurements 
must be made for 75% of all the scheduled sampling dates in each 
quarter of the year, and generally, three years of representative 
monitoring data that meet the 75 percent criterion should be utilized, 
where available.
    During the 1992-1994 period, the data collected by ADEQ meets the 
completeness criterion for all quarters at both the Paul Spur and 
Douglas monitors except for the second quarter of year 1992 at the Paul 
Spur monitor and the fourth quarter of year 1992 at both monitors. 
During the second quarter of 1992, the Paul Spur monitor was two 
samples short of the 75% criterion, and in the fourth quarter of 1992, 
both monitors were one sample short of the criterion. As noted for 
Hayden and Nogales, EPA may find that data not meeting the completeness 
criterion suffice to show attainment. See 40 CFR part 50, appendix K, 
section 2.3(b).
    In this instance, we find that the available data is sufficient to 
determine whether the area attained the standard by the applicable 
attainment date. First, we note the large extent to which the maximum 
monitored levels during the 1992-1994 period (132 [mu]g/m\3\ at the 
Paul Spur monitor and 138 [mu]g/m\3\ at the Douglas monitor--see table 
3 above) fall below the applicable standard (150 [mu]g/m\3\). We also 
note that 10 of the 12 quarters in question were complete (based on the 
75% criterion) at the Paul Spur monitor and 11 of the 12 quarters in 
question were complete at the Douglas monitor, and that the quarters 
that did not meet the criterion were but one or two samples short. 
Further, we have reviewed the monitoring data for year 1995, which is 
comprised of three quarters of data meeting the completeness criterion 
at the Paul Spur monitor and four quarters of data meeting the 
completeness criterion at the Douglas site, and during which the 
maximum 24-hour concentration was, at 77 [mu]g/m\3\, (Paul Spur) and 63 
[mu]g/m\3\ (Douglas), well below the standard, providing further 
evidence that the area attained by the applicable attainment date.
    Based on our rationale presented above, we find the available data 
sufficient to determine whether the Paul Spur/Douglas nonattainment 
area met the PM10 standard by December 31, 1994 (i.e., the 
applicable attainment date), and based on our review of the air quality 
data during the three-year period ending with the December 31, 1994 
attainment date (and summarized above in table 3), we find that the 
expected number of exceedances per year for the Paul Spur/Douglas 
PM10 nonattainment area for 1992 to 1994 was 0 days per 
year. With less than an annual expected exceedance rate for the 24-hour 
PM10 NAAQS of 1.0, these data represent attainment of the 
standard. Therefore, EPA has determined that the Paul Spur/Douglas 
PM10 nonattainment area attained the PM10 NAAQS 
by the applicable attainment date.

B. Does more recent air quality data also show attainment?

1. Hayden PM10 Nonattainment Area
    Since 1994, ADEQ has continued to operate a PM10 monitor 
at the Old Town Jail in Hayden. ADEQ has, however, changed monitoring 
methods, and, for a while, operated a second monitor for precision 
measurement (audit) purposes. Since the second quarter of 2009, ADEQ 
has operated a single TEOM (i.e., tapered element oscillating 
microbalance) monitor on a continuous-running basis at the Old Town 
Jail site in Hayden. In addition, since 2003, the Pinal County Air 
Quality Control District (AQCD) has operated a PM10 hi-
volume sampler on an every sixth day schedule along the Florence-Kelvin 
Highway near Riverside, Arizona, in the western portion of the Hayden 
PM10 nonattainment area (``Riverside monitor'').
    While not all years since 1994 have complete data (based on the 75% 
criterion), only one exceedance (158 [mu]g/m\3\ in 1997) at the Hayden 
site was monitored until year 2006, when ADEQ added the TEOM working in 
parallel with the one-day-in-six partisol sampler at the Old Town Jail 
site. In 2006 and 2007, four and five exceedances were measured by the 
TEOM, respectively. ADEQ did not operate the TEOM in 2008, and in 2009, 
ADEQ resumed operation of the TEOM beginning in the second quarter. 
Only one exceedance (225 [mu]g/m\3\) was measured by the TEOM over the 
final three quarters of 2009. Meanwhile, ADEQ continued operating the 
partisol sampler over the 2006-2008 period but discontinued the sampler 
after the end of the first quarter of 2009. At the Riverside monitor, 
Pinal County AQCD has measured no exceedances of the PM10 
standard, and maximum 24-hour PM10 concentrations measured 
there are well below the standard.
    During the most recent three-year calendar period (2007-2009), at 
the Hayden monitoring site, neither the partisol sampler nor the TEOM 
provide a complete data set for the purpose of determining whether the 
area is currently attaining the standard. The partisol sampler provides 
data for 9 of the 12 quarters, while the TEOM provides data for 7 of 
the 12 quarters. Based on the partisol sampler, this incomplete data 
set suggests that the area is currently attaining the standard because 
no exceedances were measured. The samples collected using the TEOM, 
however, suggest otherwise, with a total of six exceedances over the 
discontinuous course of its operation. Based on the TEOM, six 
exceedances over the course of this period of time is sufficient for us 
to conclude that the Hayden PM10 nonattainment area is not 
currently attaining the standard. In 2010, through the first two 
quarters, the TEOM has not recorded any exceedances; if this trend 
continues, then, next year, based on 2008-2010 data, the current 
attainment status of the Hayden area may change once again.
2. Nogales PM10 Nonattainment Area
    Since 1994, ADEQ has continued to operate a PM10 
monitoring site at the Post Office in Nogales, but has replaced the 
dichot sampler with a partisol sampler, and has added a continuous-

[[Page 67226]]

running beta attenuation monitor (BAM).
    The data from AQS indicates that, while the area attained the 
standard by the applicable attainment date, ambient PM10 
concentrations worsened in the late 1990's to the point where 
exceedances under current conditions have been measured nearly every 
year. Based on the past three calendar years (2007-2009) of complete 
quality-assured data, we find that the annual expected exceedance rate 
for the 24-hour PM10 NAAQS for the Nogales area is 9.7 
(based on the BAM). Based on the partisol sampler, the annual expected 
exceedance rate for the 24-hour PM10 NAAQS of 4.2, but the 
higher of the two samplers is used to determine whether the area is 
attaining the standard. Because the annual expected exceedance rate for 
the area (9.7) is greater than 1.0, we conclude that the area is not 
currently attaining the PM10 standard.
    EPA's determination that the Nogales area is not currently 
attaining the PM10 standard does not result in 
reclassification of this ``moderate'' area to ``serious'' by operation 
of law because such reclassification is tied to air quality conditions 
``as of the attainment date,'' (see CAA sections 179(c)(1) and 
188(b)(2)), and, as discussed in section II.A.2 of this document, we 
have concluded that the Nogales area attained the standard by the 
attainment date. We do, however, plan to address the PM10 
planning needs for the Nogales area over the next few years. We also 
note that the Nogales planning area has been designated as 
nonattainment for the 2006 24-hour NAAQS for fine particles (generally 
referring to particles less than or equal to 2.5 micrometers in 
diameter, PM2.5) (74 FR 58688, November 13, 2009), which has 
triggered a separate air quality planning process.
3. Paul Spur/Douglas PM10 Nonattainment Area
    Since 1994, ADEQ has continued to operate PM10 
monitoring sites near the Paul Spur Chemical Lime Plant (``Paul Spur 
monitor'') and in the City of Douglas (``Douglas monitor''). At the 
Paul Spur monitoring site, ADEQ replaced the dichot sampler with a 
partisol sampler, and added a second partisol sampler for precision 
measurement purposes. Both monitors continue to run on a one-day-in-six 
monitoring schedule. At the Douglas monitoring site, ADEQ replaced the 
dichot sampler with a partisol sampler and, in 1998, re-located the 
monitor to a nearby location, the Red Cross building just across from 
the park on 15th Street, where it continues to operate today.
    The data from AQS indicates that only two exceedances of the 
PM10 standard have been measured in the Paul Spur/Douglas 
nonattainment area over the past 15 years. Both were measured at the 
Paul Spur monitoring site. One exceedance, 206 [mu]g/m\3\, was measured 
in 2003 and the other (159 [mu]g/m\3\) was measured in 2008.\9\ Based 
on the past three calendar years (2007-2009) of complete quality-
assured data, we find that the annual expected exceedance rate for the 
24-hour PM10 NAAQS for the Paul Spur/Douglas area is 2.0 
(which is calculated by taking into account the one-day-in-six 
monitoring schedule).\10\ Because the annual expected exceedance rate 
for the area (2.0) is greater than 1.0, we conclude that the area is 
not currently attaining the PM10 standard.
---------------------------------------------------------------------------

    \9\ Both of these exceedances were flagged by ADEQ as 
exceptional events, but EPA has not concurred on the flags.
    \10\ The collocated (audit) monitor measured two exceedances 
during 2008, but on both sample-days, the primary monitor also took 
valid samples, and thus, the measurements from the co-located 
samplers are not used to report air quality from the site. See 40 
CFR part 58, appendix A, section 3.2.5.
---------------------------------------------------------------------------

    EPA's determination that the Paul Spur/Douglas area is not 
currently attaining the PM10 standard does not result in 
reclassification of this ``moderate'' area to ``serious'' by operation 
of law because such reclassification is tied to air quality conditions 
``as of the attainment date,'' (see CAA sections 179(c)(1) and 
188(b)(2)), and, as discussed in section II.A.3 of this document, we 
have concluded that the Paul Spur/Douglas area attained the standard by 
the attainment date. We do, however, plan to address the 
PM10 planning needs for the Paul Spur/Douglas area over the 
next few years.

III. EPA's Final Action

    Under section 188(b)(2) of the Clean Air Act, and based on 
sufficient, quality-assured data, we find that the Hayden, Nogales, and 
Paul Spur/Douglas PM10 nonattainment areas attained the 24-
hour PM10 NAAQS by the applicable attainment date, December 
31, 1994. On the basis of this determination, EPA concludes that these 
three ``moderate'' nonattainment areas are not subject to 
reclassification to ``serious'' by operation of law. This action is not 
a redesignation to attainment under CAA section 107(d)(3) because we 
have not yet approved maintenance plans for these areas as meeting the 
requirements of section 175A of the CAA or determined that the areas 
have met the other CAA requirements for redesignation.
    On the basis of a review of more recent ambient monitoring data, 
EPA has determined that the Hayden, Nogales, and Paul Spur/Douglas 
nonattainment areas are not currently attaining the PM10 
standard. EPA's determination that the Hayden, Nogales, and Paul Spur/
Douglas areas are not currently attaining the PM10 standard 
does not result in reclassification of these ``moderate'' areas to 
``serious'' by operation of law because such reclassification is tied 
to air quality conditions ``as of the attainment date,'' (see CAA 
sections 179(c)(1) and 188(b)(2)), and EPA has determined that both 
areas attained the standard by the applicable attainment date.
    We are publishing this rule without prior proposal because the 
Agency views this as a noncontroversial action and anticipates no 
adverse comments. However, in the proposed rules section of this 
Federal Register publication, EPA is publishing a separate document 
that will serve as the proposal should adverse comments be filed. This 
action will be effective January 3, 2011, without further notice unless 
the EPA receives relevant adverse comments by December 2, 2010.
    If we receive such comments, then we will publish a document 
withdrawing the final rule and informing the public that the rule will 
not take effect. All public comments received will then be addressed in 
a subsequent final rule based on the proposed rule. We will not 
institute a second comment period. Parties interested in commenting 
should so at this time. If no such comments are received, the public is 
advised that this rule will be effective on January 3, 2011 and no 
further action will be taken on the proposed rule.

IV. Statutory and Executive Order Reviews

    This action merely makes a determination based on air quality data 
and does not impose any additional Federal requirements. For that 
reason, this action:
     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.);

[[Page 67227]]

     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
     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.
    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the 
Small Business Regulatory Enforcement Fairness Act of 1996, generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report, which includes a copy of the rule, 
to each House of the Congress and to the Comptroller General of the 
United States. EPA will submit a report containing this action and 
other required information to the U.S. Senate, the U.S. House of 
Representatives, and the Comptroller General of the United States prior 
to publication of the rule in the Federal Register. A major rule cannot 
take effect until 60 days after it is published in the Federal 
Register. This action is not a ``major rule'' as defined by 5 U.S.C. 
804(2).
    Under section 307(b)(1) of the Clean Air Act, petitions for 
judicial review of this action must be filed in the United States Court 
of Appeals for the appropriate circuit by January 3, 2011. Filing a 
petition for reconsideration by the Administrator of this final rule 
does not affect the finality of this action for the purposes of 
judicial review nor does it extend the time within which a petition for 
judicial review may be filed, and shall not postpone the effectiveness 
of such rule or action. Parties with objections to this direct final 
rule are encouraged to file a comment in response to the parallel 
notice of proposed rulemaking for this action published in the proposed 
rules section of today's Federal Register, rather than file an 
immediate petition for judicial review of this direct final rule, so 
that EPA can withdraw this direct final rule and address the comment in 
the proposed rulemaking. This action may not be challenged later in 
proceedings to enforce its requirements. (See section 307(b)(2).)

List of Subjects in 40 CFR Part 81

    Environmental protection, Air pollution control, National parks, 
Particulate matter, Wilderness areas.

    Authority:  42 U.S.C. 7401 et seq.

    Dated: October 25, 2010.
Jared Blumenfeld,
Regional Administrator, EPA Region IX.
[FR Doc. 2010-27634 Filed 11-1-10; 8:45 am]
BILLING CODE 6560-50-P

