Ambient Air Monitoring Regulations: Correcting and Other Amendments

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

[Federal Register: June 12, 2007 (Volume 72, Number 112)]
[Rules and Regulations]
[Page 32193-32212]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr12jn07-10]

-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 53 and 58
[EPA-HQ-OAR-2004-0018; FRL-8308-7]
RIN 2060-AO06

AGENCY: Environmental Protection Agency (EPA).
ACTION: Direct final rule.

-----------------------------------------------------------------------

SUMMARY: The EPA is taking direct final action on ``Ambient Air
Monitoring Regulations: Correcting and Other Amendments'' to correct
and clarify parts of a recent final rule published on October 17, 2006,
that amended the ambient air monitoring requirements for criteria
pollutants. These errors included several instances where the wording
in the preamble and regulatory text were not completely consistent,
several regulatory text passages that contained some imprecise
language, two instances of regulatory text omission, an outdated
address reference, and numerous publication errors in tables and
equations. EPA is also amending the monitoring rule to allow EPA
Regional Administrators to approve departures from the minimum number
of PM₁₀ monitors otherwise specified in the rule.
The October 17, 2006, final rule revised requirements for reference
and equivalent method determinations, modified requirements for general
monitoring network design, and modified other requirements pertaining
to quality assurance, annual network plans and assessments, data
reporting, monitoring methodology, and probe and monitor siting
criteria. All other preamble and regulatory text printed in the October
17, 2006, final rule is correct.

DATES: This rule is effective on September 10, 2007, without further
notice, unless EPA receives adverse comment by July 12, 2007. If we
receive adverse comment, we will publish a timely withdrawal in the
Federal Register informing the public that some or all of the
amendments in this rule will not take effect.

ADDRESSES: Submit your comments, identified under Docket ID No. EPA-HQ-
OAR-2004-0018 by one of the following methods:
• http://www.regulations.gov. Follow the on-line instructions for
submitting comments.
• E-mail: a-and-r-docket@epa.gov.
• Fax: (202) 566-1741.
• Mail: Ambient Air Monitoring Regulations: Correcting and
Other Amendments, Environmental Protection Agency, Mailcode: 6102T,
1200 Pennsylvania Avenue, NW., Washington, DC 20460. Please include a
total of 2 copies.
• Hand Delivery: EPA Docket Center, 1301 Constitution
Avenue, NW., Room 3334, Washington, DC. Such deliveries are only
accepted during the Docket's normal hours of operation, and special
arrangements should be made for deliveries of boxed information.
Instructions: Direct your comments to Docket ID No. EPA-HQ-OAR-
2004-0018. The EPA's policy is that all comments received 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 information claimed to be
Confidential Business Information (CBI) or other information whose
disclosure is restricted by statute. Do not submit information that you
consider to be CBI or otherwise protected through http://www.regulations.gov
or e-mail. The http://www.regulations.gov website is an ``anonymous access''
system, which means 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 comment directly to EPA without going through
http://www.regulations.gov, your e-mail address will be automatically captured
and included as part of the comment that is placed in the public docket
and made available on the internet. 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: All documents in the docket are listed in the
http://www.regulations.gov index. Although listed in the index, some
information is not publicly available, e.g., CBI or other information
whose disclosure is restricted by statute. Certain other material, such
as copyrighted material, will be publicly available only in hard copy.
Publicly available docket materials are available either electronically in
http://www.regulations.gov or in hard copy at the Revisions to the
Ambient Air Monitoring Regulations Docket, EPA/DC, EPA West, Room 3334,
Constitution Ave., NW., Washington, DC. The Public Reading Room is open
from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal
holidays. The telephone number for the Public Reading Room is (202)
566-1744, and the telephone number for the Air Docket is (202) 566-1742.

FOR FURTHER INFORMATION CONTACT: Mr. Lewis Weinstock, Air Quality
Assessment Division (C304-06), Office

[[Page 32194]]

of Air Quality Planning and Standards, U.S. Environmental Protection
Agency, Research Triangle Park, North Carolina 27711; telephone number:
(919) 541-3661; fax number: (919) 541-1903; e-mail address:
weinstock.lewis@epa.gov.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Why Is EPA Using a Direct Final Rule?
II. Does This Action Apply to Me?
III. Judicial Review
IV. Authority
V. Overview of the October 17, 2006 Rule Changes
VI. This Action
A. Correction to Special Purpose Monitors
B. Clarification to Requirement for Collocating Required
Continuous Fine Particle (PM_2.5) Monitors
C. Clarification to Operating Schedule Requirements for Filter-
Based Manual PM_2.5 Samplers
D. Standard versus Daylight Savings Time Reference
E. Corrections to Regulatory Text on Particulate Matter
(PM₁₀) Network Design Criteria
F. Additional Regional Administrator Flexibility in Applying
PM₁₀ Minimum Monitoring Requirements
G. Correction to Division Name and Address Reference
H. Clarification to Conditions for Waiving Regional
Administrator Comment Period on Submitted Annual Monitoring Network Plans
I. Typographical Corrections
VII. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review
B. Paperwork Reduction Act
C. Regulatory Flexibility Act
D. Unfunded Mandates Reform Act
E. Executive Order 13132: Federalism
F. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
G. Executive Order 13045: Protection of Children From
Environmental Health and Safety Risks
H. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income Populations
I. Executive Order 13211: Actions That Significantly Affect
Energy Supply, Distribution, or Use
J. National Technology Transfer Advancement Act
K. Congressional Review Act

I. Why Is EPA Using a Direct Final Rule?

The EPA is publishing this rule without a prior proposed rule
because we view this as a non-controversial action and anticipate no
adverse comment. None of the proposed changes creates additional
regulatory requirements on affected entities compared to those that
were promulgated in the final rule that was published in the Federal
Register on October 17, 2006. However, in the ``Proposed Rules''
section of this Federal Register, we are publishing a separate document
that will serve as the proposed rule to make corrections to the Ambient
Air Monitoring Regulations if relevant adverse comments are received on
one or more of the amendments in this direct final rule as described in
sections VI.A. through VI.I of this preamble. We will not institute a
second comment period on this action. Any parties interested in
commenting must do so at this time. For further information about
commenting on this rule, see the ADDRESSES section of this document. If
EPA receives relevant adverse comment on one or more of the amendments
included in this rulemaking, we will publish a timely withdrawal in the
Federal Register indicating which amendment or amendments we are
withdrawing. The provisions that are not withdrawn will become
effective on the date set out above, notwithstanding any relevant
adverse comment on any other provision.

II. Does This Action Apply to Me?

Categories and entities potentially regulated by this action include:

----------------------------------------------------------------------------------------------------------------
Category NAICS code \1\ Examples of regulated entities
----------------------------------------------------------------------------------------------------------------
Industry...................................... 334513 Manufacturer, supplier, distributor, or vendor
541380 of ambient air monitoring instruments;
analytical laboratories or other monitoring
organizations that elect to submit an
application for a reference or equivalent
method determination under 40 CFR part 53.
Federal Government............................ 924110 Federal agencies (that conduct ambient air
monitoring similar to that conducted by States
under 40 CFR part 58 and that wish EPA to use
their monitoring data in the same manner as
State data) or that elect to submit an
application for a reference or equivalent
method determination under 40 CFR part 53.
State/territorial/local/tribal government..... 924110 State, territorial, and local air quality
management programs that are responsible for
ambient air monitoring under 40 CFR part 58 or
that elect to submit an application for a
reference or equivalent method determination
under 40 CFR part 53 or for an approved
regional method approved under 40 CFR part 58
appendix C. The proposal also may affect Tribes
that conduct ambient air monitoring similar to
that conducted by States and that wish EPA to
use their monitoring data in the same manner as
State monitoring data.
----------------------------------------------------------------------------------------------------------------
\1\ North American Industry Classification System.

This table is not intended to be exhaustive, but rather provides a
guide for readers regarding entities likely to be regulated by this
action. This table lists the types of entities that EPA is now aware
could potentially be regulated by this action. Other types of entities
not listed in the table could also be regulated. To determine whether
your facility or Federal, State, local, tribal, or territorial agency
is regulated by this action, you should carefully examine the
requirements for reference or equivalent method determinations in 40
CFR part 53, subpart A (General Provisions) and the applicability
criteria in 40 CFR 51.1 of EPA's requirements for State Implementation
Plans (SIPs). If you have questions regarding the applicability of this
action to a particular entity, consult the person listed in the
preceding FOR FURTHER INFORMATION CONTACT section.

III. Judicial Review

Under section 307(b)(1) of the Clean Air Act (CAA), judicial review
of the direct final rule amendments is available only by filing a
petition for review in the U.S. Court of Appeals for the District of
Columbia by August 13, 2007. Under section 307(d)(7)(B) of the CAA,
only an objection to the direct final rule amendments that was raised
with reasonable specificity during the period for public comment can be
raised during judicial review. Moreover, under section 307(b)(2) of the
CAA, the requirements established by the direct final rule amendments
may not be challenged separately in any civil or criminal proceedings
brought by EPA to enforce these requirements.

IV. Authority

The EPA rules for ambient air monitoring are authorized under
sections 110, 301(a), and 319 of the CAA. Section 110(a)(2)(B) of the
CAA requires that each SIP provide for the establishment and operation
of devices,

[[Page 32195]]

methods, systems, and procedures needed to monitor, compile, and
analyze data on ambient air quality and for the reporting of air
quality data to EPA. Section 103 authorizes, among others, research and
investigations relating to the causes, effects, extent, prevention and
control of air pollution. Section 301(a) of the CAA authorizes EPA to
develop regulations needed to carry out EPA's mission and establishes
rulemaking requirements. Uniform criteria to be followed when measuring
air quality and provisions for daily air pollution index reporting are
required by CAA section 319.

V. Overview of the October 17, 2006 Rule Changes

On October 17, 2006 (71 FR 61236), EPA amended the rules for
ambient air monitoring of criteria pollutants. The rule amendments
established limited ambient air monitoring requirements for particles
between 2.5 and 10 micrometers (µm) in diameter (PM_10-_2.5) to support continued
research into these particles' distribution, sources, and health effects.
The rule amendments required each State to operate one to three ``NCore''
monitoring stations that will take an integrated, multipollutant
approach to ambient air monitoring. In addition, the rule amendments
modified the general monitoring network design requirements for minimum
numbers of ambient air monitors to focus on populated areas with air
quality problems and to reduce significantly the requirements for
criteria pollutant monitors that have measured ambient air
concentrations well below the applicable National Ambient Air Quality
Standards. The rule amendments also revised certain provisions
regarding monitoring network descriptions and periodic assessments,
quality assurance, and data certifications. A number of the amendments
related specifically to monitoring of fine particles (referring to
particles less than or equal to 2.5 µm in diameter,
PM_2.5), revising the requirements for reference and
equivalent method determinations (including specifications and test
procedures) for fine particle monitors.

VI. This Action

EPA is taking the following actions:
• Correcting a statement in the regulatory text pertaining
to the potential comparability of data collected from Special Purpose
Monitors (SPM) with approved alternative quality assurance plans to the
National Ambient Air Quality Standards (NAAQS).
• Correcting a statement in the preamble with regard to the
requirement for collocating required continuous PM_2.5
monitors and clarifying associated regulatory text.
• Clarifying several ambiguous regulatory text passages
pertaining to operating schedules for manual PM_2.5 samplers.
• Correcting a reference regarding standard versus daylight
savings time.
• Restoring two instances of regulatory text that were
inadvertently omitted from the network design for monitoring particles
less than or equal to 10 µm in diameter (PM₁₀).
• Adding authority for the Regional Administrator,
consistent with the authority that already exists for PM_2.5
and ozone, to allow monitoring agencies to deviate from PM₁₀
monitoring requirements.
• Updating an organizational address reference within
regulatory text pertaining to quality assurance requirements.
• Clarifying the conditions when the EPA Regional
Administrator is not required to offer a public comment opportunity
prior to approving a State's annual monitoring network plan.
• Correcting numerous typographical errors in tables and equations.

A. Correction to Special Purpose Monitors

The intent of 40 CFR 58.20(c) (published at 71 FR 61302) was to
describe the conditions when data from an SPM using a Federal reference
method (FRM), Federal equivalent method (FEM), or Approved Regional
Method (ARM) which has operated for more than 24 months is eligible for
comparison to the relevant NAAQS. The rule text states that all data
from an SPM is eligible for comparison to the relevant NAAQS unless the
data from the particular monitor came from a period when the
requirements of appendix A to part 58 (Quality Assurance Requirements
for SLAMS, SPMs, and PSD Air Monitoring) or an approved alternative,
appendix C to part 58 (Ambient Air Quality Monitoring Methodology), or
appendix E to part 58 (Probe and Monitoring Path Siting Criteria for
Ambient Air Monitoring) were not met in practice. This text does not
reflect EPA's actual intention. Instead, as discussed in the preamble
(71 FR 61253), the intention of the October 17, 2006, final rule was
that if the Regional Administrator approved an alternative quality
assurance plan in place of the requirements of appendix A to part 58,
the data from the affected SPM would not be eligible for comparison to
the relevant NAAQS. The unintentional inclusion in the rule text of the
phrase ``or an approved alternative'' implied that data from SPMs
operating during a period when approved alternative quality assurance
requirements were in effect, rather than appendix A requirements, would
still be eligible for comparison to the relevant NAAQS.
The EPA provided the Regional Administrator with the authority to
approve an alternative to the requirements of appendix A to part 58
with respect to SPM sites when meeting those requirements would be
physically and/or financially impractical due to physical conditions at
the monitoring site and the requirements were not essential to
achieving the intended data objectives of the SPM site.
Therefore, EPA is clarifying the regulatory text by deleting the
aforementioned words referencing alternative quality assurance plans.
The corrected rule text 40 CFR 58.20(c) reads: ``All data from an SPM
using an FRM, FEM, or ARM which has operated for more than 24 months is
eligible for comparison to the relevant NAAQS, subject to the
conditions of Sec. 58.30, unless the air monitoring agency
demonstrates that the data came from a particular period during which
the requirements of appendix A, appendix C, or appendix E to this part
were not met in practice.''

B. Clarification to Requirement for Collocating Required Continuous
Fine Particle (PM_2.5) Monitors

The regulatory text in 40 CFR part 58, appendix D (Network Design
Criteria for Ambient Air Quality Monitoring), section 4.7.2 (71 FR 61322)
describes the minimum requirements for operating continuous
PM_2.5 analyzers.\1\ The text requires States to operate a
minimum number of continuous PM_2.5 analyzers equal to at
least one-half (round up) the minimum required FRM/FEM/ARM
PM_2.5 sites listed in Table D-5 of appendix D to part 58. At
least one required FRM/FEM/ARM PM_2.5 monitor in each MSA
must be collocated with a continuous analyzer. For example, if a MSA
had three required FRM/FEM/ARM PM_2.5 monitors, then two
continuous monitors are required, and at least one of those continuous
monitors must be collocated (placed at the same site) with one of the
FRM/FEM/ARM PM_2.5 monitors. The second

[[Page 32196]]

required continuous monitor could be collocated with one of the
remaining two required FRM/FEM/ARM PM_2.5 monitors at another
site, or be located at a separate site based on monitoring objectives.
The EPA did not intend that the continuous analyzers required under
section 4.7.2 be required to be collocated with each other.
---------------------------------------------------------------------------

\1\ In 40 CFR part 58 and in this preamble, the terms monitor,
analyzer, and sampler are sometimes used interchangeably. Monitor is
the more general term. Most often, analyzer means a self-contained
monitor which can produce concentration data on-site. Sampler means
a device that collects a sample (e.g., a filter) which must be further
processed at an outside laboratory to obtain the concentration value.
---------------------------------------------------------------------------

The October 17, 2006, rule text matches our intended meaning. However,
when referencing this rule requirement in the preamble (71 FR 61263),
EPA incorrectly stated that the collocation requirement was
adopted to address concerns about whether required continuous monitors
needed to be collocated with a matching second continuous monitor, and
that the final rule only required one of all the required
PM_2.5 continuous monitors in each MSA to have ``such a
collocated match.'' This unintentional statement could be construed as
a requirement for collocating two continuous monitors with each other,
in addition to the requirement for collocation with at least one
required FRM/FEM/ARM monitor, leading to the conclusion that EPA was
requiring three PM_2.5 monitors (two continuous, one filter-
based) at the first required site, subject to the requirements of
section 4.7.2. Moreover, it was not our intention to require a second
continuous monitor be sited with an FEM or ARM that itself provides
continuous data.
Therefore, EPA is clarifying the regulatory text to make clear the
intentions described above. The EPA is also clarifying that an
associated reference to quality assurance/quality control procedures
refers to the continuous monitoring requirement by adding the words
``for these required continuous analyzers.'' The corrected provision of
40 CFR part 58, appendix D, section 4.7.2 now reads: ``Requirement for
Continuous PM_2.5 Monitoring. The State, or where
appropriate, local agencies must operate continuous PM_2.5
analyzers equal to at least one-half (round up) the minimum required
sites listed in Table D-5 of this appendix. At least one required
continuous analyzer in each MSA must be collocated with one of the
required FRM/FEM/ARM monitors, unless at least one of the required FRM/
FEM/ARM monitors is itself a continuous FEM or ARM monitor, in which
case no collocation requirement applies. State and local air monitoring
agencies must use methodologies and quality assurance/quality control
(QA/QC) procedures approved by the EPA Regional Administrator for these
required continuous analyzers.''

C. Clarification to Operating Schedule Requirements for Filter-Based
Manual PM_2.5 Samplers

The regulatory text in 40 CFR 58.12(d) (71 FR 61299) describes the
required sampling frequency for manual filter-based PM_2.5
samplers. Manual PM_2.5 samplers at SLAMS stations must
operate on at least a 1-in-3 day schedule at sites which do not also
have a collocated continuously operating PM_2.5 monitor. For
SLAMS PM_2.5 sites with both manual and continuous
PM_2.5 monitors operating, other than NCore stations,
monitoring agencies may request approval from the EPA Regional
Administrator for a reduction to 1-in-6 day PM_2.5 sampling
or for seasonal sampling. The EPA Regional Administrator may grant
sampling frequency reductions after consideration of factors including,
but not limited to, the historical PM_2.5 data quality
assessments, the location of current PM_2.5 design value
sites, and the regulatory data needs of States and EPA. The regulatory
text provides specific criteria under which a manual PM_2.5
sampler at a SLAMS station cannot be exempted by the Regional
Administrator from at least 1-in-3 day sampling, and also includes a
separate provision describing when a daily sampling schedule is
required. The textual length of 40 CFR 58.12(d)(1) as well as the
specific wording of certain statements could create difficulty in
understanding the intended operating schedule requirements for manual
PM_2.5 samplers. Therefore, EPA is clarifying 40 CFR
58.12(d)(1) as described below.
The first sentence of 40 CFR 58.12(d)(1) stated that: ``Manual
PM_2.5 samplers at SLAMS stations other than NCore stations
must operate on at least a 1-in-3 day schedule at sites without a
collocated continuously operating PM_2.5 monitor.'' This
statement could be construed as meaning that manual PM_2.5
samplers at NCore stations were not required to maintain at least a 1-
in-3 day schedule. The rule in fact does require manual
PM_2.5 samplers at NCore stations to maintain at least a 1-
in-3 day sampling schedule, as later noted in 40 CFR 58.12(d)(2), and
these samplers are not eligible for sampling frequency relief.
Therefore, EPA is clarifying the rule text by deleting the phrase
``other than NCore stations'' from first sentence of 40 CFR
58.12(d)(1).
Another potential ambiguity regarding the 1-in-3 day sampling
frequency provision of 40 CFR 58.12(d)(1) is its geographic
applicability. Since the regulatory language did not specify that the
1-in-3 day sampling frequency requirement be applied only in areas in
which PM_2.5 monitoring is required, this requirement could
be interpreted as applying to any manual PM_2.5 sampler
within a State that recorded the highest design value ``in an area''
whether or not any PM_2.5 monitors were even required in that
area according to 40 CFR part 58, appendix D. The EPA is concerned that
such an interpretation would create a disincentive to monitoring by
potentially requiring States that operated discretionary SLAMS monitors
to sample on a 1-in-3 day frequency even though the monitor was in
excess of minimum monitoring requirements. Therefore, the first
sentence of 40 CFR 58.12(d)(1)(i) is amended to read: ``Manual
PM_2.5 samplers at required SLAMS stations without a
collocated continuously operating PM_2.5 monitor must operate
on at least a 1-in-3 day schedule.'' In this rule text, ``required
SLAMS stations'' refers to minimum monitoring requirements as specified
in 40 CFR part 58, appendix D, section 4.7. It does not include SPMs;
therefore SPMs are not required to sample on a 1-in-3 day schedule.
After stating the 1-in-3 day sampling requirement, the rule text at
40 CFR 58.12(d)(1)(ii) goes on to allow the Regional Administrator to
grant a reduction of this schedule to 1-in-6 day for SLAMS
PM_2.5 sites with both manual and continuous PM_2.5
monitors operating. In this context, the rule text contains a
duplicated reference to SLAMS PM_2.5 sites; the second
reference, ``at SLAMS stations,'' is removed in the corrected rule
language since the opening part of the sentence already states the
applicability of the provision to SLAMS PM_2.5 sites. The
text goes on to describe two situations in which a manual
PM_2.5 sampler at a required SLAMS station could not be
granted sampling frequency relief by the Regional Administrator from
the minimum 1-in-3 day sampling schedule. In the first situation, the
phrase: ``Sites that have design values that are within plus or minus
10 percent of the NAAQS'' could be construed as applying to all sites
within a particular area that have design values that are within plus
or minus 10 percent of the NAAQS, when the intention was to apply the
provision only to the site with the highest value in a particular area
calculated in accordance with 40 CFR part 50, appendix N
(Interpretation of the National Ambient Air Quality Standards for
PM_2.5).\2\ In the second

[[Page 32197]]

situation, the phrase: ``and sites where the 24-hour values exceed the
NAAQS for a period of 3 years are required to maintain at least a 1-in-
3 day sampling frequency'' created ambiguity about whether the
provision was applicable in situations where a single 24-hour value
exceeded the NAAQS at a particular site during only 1 or 2 years of a
3-year period. The EPA's intention was that at least one 24-hour value
had to exceed the NAAQS in each of the years comprising the 3-year
period situation for the provision to apply.
---------------------------------------------------------------------------

\2\ EPA notes that the term ``design value'' as defined in the
final rule (40 CFR part 58.1, 71 FR 61296) is the calculated
concentration of a pollutant according to the applicable appendix of
part 50 for the highest monitoring site in an attainment or
nonattainment area, and that EPA's usage of ``design value'' in the
rule text was consistent with this definition.
---------------------------------------------------------------------------

Also, the regulatory text could be construed as requiring 1-in-3
day manual PM_2.5 sampling at all sites within a particular
area that have design values within the plus or minus 10 percent
criteria, regardless of whether the site is required and regardless of
the potential availability of continuous PM_2.5 FEM or ARM
monitors which inherently would provide every-day data eligible for
comparison to the NAAQS. The EPA anticipates the increasing
availability of approved FEM and ARM methods over the next few years,
and expects that many such approved continuous monitors will be
deployed at sites formerly dedicated to manual filter-based FRM or FEM
PM_2.5 samplers, including design value sites subject to the
plus or minus 10 percent criteria when compared with the 24-hour
PM_2.5 NAAQS. The EPA supports the deployment of approved FEM
or ARM continuous PM_2.5 methods to meet appropriate
monitoring objectives as such monitors become available, and thus we
did not intend to require 1-in-3 day sampling utilizing manual
PM_2.5 methods at design value sites, or any other sites,
where monitoring agencies have deployed an approved continuous FEM or ARM.
The clarified language of the restriction related to being within
plus or minus 10 percent of the NAAQS now reads: ``Required SLAMS
stations whose measurements determine the design value for their area
and that are within plus or minus 10 percent of the NAAQS, and all
required sites where one or more 24-hour values have exceeded the NAAQS
each year for a consecutive period of at least 3 years, are required to
maintain at least a 1-in-3 day sampling frequency. A continuously
operating FEM or ARM PM_2.5 monitor satisfies this requirement.''
At the end of 40 CFR 58.12(d)(1), EPA specified that manual
PM_2.5 samplers at sites that have a design value within plus
or minus 5 percent of the daily PM_2.5 NAAQS must have an FRM
or FEM operate on a daily schedule. As with the previously discussed
phrasing in the context of the 1-in-3 day sampling requirement, this
text could be construed as applying to all sites within a particular
area that have design values that are within plus or minus 5 percent of
the NAAQS, when the intention was to apply the provision only to the
required SLAMS site with the highest value in a particular area. Also,
the above described concern regarding the acceptability of continuous
PM_2.5 analyzers applies in the case of this plus or minus 5
percent criterion, and a similar clarification to the rule text is
appropriate.
Therefore, EPA is clarifying 40 CFR 58.12(d)(1) and for purposes of
clarity is adding subparagraph (iii). It will read: ``Required SLAMS
sites whose measurements determine the design value for their area and
that are within plus or minus 5 percent of the daily PM_2.5
NAAQS must have an FRM or FEM operate on a daily schedule. A
continuously operating FEM or ARM PM_2.5 monitor satisfies
this requirement.''
The EPA notes that only population-oriented monitors are subject to
the previously described percent-dependent sampling frequency
requirements. In 40 CFR 58.30 (Special Considerations for Data
Comparisons to the NAAQS), sites must be population-oriented to be
comparable to either the annual or daily PM_2.5 NAAQS. By
implication, design value sites must be NAAQS comparable, therefore
non-population oriented sites would not be affected by the plus or
minus 10 percent or plus or minus 5 percent provisions.
As previously mentioned, EPA is aware that the length of 40 CFR
58.12(d)(1) creates the potential for ambiguity in the applicability of
individual provisions related to sampling frequency requirements. To
clarify the applicability of such provisions, EPA has restructured 40
CFR 58.12(d)(1) to create distinct paragraphs encompassing the
previously described amended language applicable to SLAMS sites without
continuously operating PM_2.5 monitors (now numbered 40 CFR
58.12(d)(1)(i)), SLAMS sites with both manual and continuous
PM_2.5 monitors (now numbered 40 CFR 58.12(d)(1)(ii)), and
design value sites within plus or minus 5 percent of the daily
PM_2.5 NAAQS (now numbered 40 CFR 58.12(d)(1)(iii)).
In 40 CFR 58.12(d)(3), manual PM_2.5 speciation samplers
at required Speciation Trends Network (STN) stations are required to
operate on a 1-in-3 day sampling frequency. The EPA intended the 1-in-3
day sampling frequency to be a minimum sampling frequency and not to
imply a prohibition against a more frequent sampling frequency, such as
a daily sampling frequency, if such a frequency is appropriate for
specific monitoring objectives. Consistent with the phraseology of
sampling frequency requirements elsewhere in the regulatory text, EPA
is correcting the aforementioned phrase to read: ``Manual
PM_2.5 speciation samplers at STN stations must operate on at
least a 1-in-3 day sampling frequency.''

D. Standard versus Daylight Savings Time Reference

40 CFR 58.12(e) requires that the operating schedule for
PM₁₀ samplers must be a 24-hour sampling period taken from
midnight to midnight (local time) to ensure national consistency. In a
1999 EPA memorandum,\3\ the use of standard time versus daylight
savings time is discussed in the context of sample collection for
particulate matter monitors, concluding with the recommendation that
monitoring agencies operate their particulate matter sampler clocks on
standard time to avoid the semi-annual time-shift issues associated
with conversion between standard time and daylight savings time.
Monitoring agencies have generally adopted the practice of keeping
their particulate matter sampler clocks on standard time since the
issuance of the 1999 memorandum. It was EPA's intention to codify the
practice of keeping particulate matter clocks on standard time in the
October 17, 2006, Revisions to the Ambient Monitoring Regulations;
however, the codifying rule text was inadvertently omitted for
PM₁₀.\4\ If the aforementioned 40 CFR 58.12(e) reference to
PM₁₀ operating schedule is left uncorrected, this could
create inconsistent interpretation of the standard versus daylight
savings time issue among monitoring agencies causing unnecessary
confusion in the interpretation of the air quality data.
---------------------------------------------------------------------------

\3\ ``Use of PM Reference Methods and Daylight Savings Time,'' J. David
Mobley; Office of Air Quality Planning and Standards, June 11, 1999.
http://www.epa.gov/ttn/amtic/files/ambient/pm25/stdtime.pdf.
\4\ The intention to base sampling on local standard time was
correctly reflected in rule text applicable to PM_2.5. 40
CFR part 50, appendix N (Interpretation of the National Ambient Air
Quality Standards for PM_2.5) reads: ``Daily values for
PM_2.5 refers to the 24-hour average concentrations of
PM_2.5 calculated (averaged from hourly measurements) or
measured from midnight to midnight (local standard time) that are
used in NAAQS computations.''
---------------------------------------------------------------------------

Therefore, EPA is correcting the reference to PM₁₀
operating schedules in

[[Page 32198]]

40 CFR 58.12(e) to read as follows: ``For PM₁₀ samplers, a
24-hour sample must be taken from midnight to midnight (local standard
time) to ensure national consistency.''

E. Corrections to Regulatory Text on Particulate Matter
(PM₁₀) Network Design Criteria

In the preamble to the final monitoring rule (71 FR 61240), EPA
stated an intention to retain the pre-existing minimum monitoring
network design requirements for PM₁₀, which are based on the
population of an MSA and its historical PM₁₀ air quality.
The EPA's intention in finalizing the regulatory text in section 4.6,
Particulate Matter (PM₁₀) Design Criteria, of 40 CFR part
58, appendix D (Network Design Criteria for Ambient Air Quality
Monitoring) (71 FR 61320) was to retain all PM₁₀-relevant
portions of the pre-existing regulatory text beginning with section
3.7, Particulate Matter Design Criteria for NAMS (see 62 FR 38820, July
18, 1997), with only minor changes necessary to maintain consistency of
monitor type terminology (e.g., to eliminate obsolete references to
National Air Monitoring Stations (NAMS)). The EPA inadvertently omitted
several passages from the pre-existing regulatory text in section 3.7
referencing PM₁₀ network design criteria. If left
uncorrected, these omissions could lead to misinterpretation of
PM₁₀ monitoring network design requirements. Three specific
textual corrections are detailed below.
First, in Table D-4, PM₁₀ Minimum Monitoring
Requirements (Number of Stations per MSA), the word ``Approximate''
which had appeared in the title of the pre-existing Table 4 was
omitted. Therefore, in order to retain the earlier language EPA is
revising the title of Table D-4 to read: ``PM₁₀ Minimum
Monitoring Requirements (Approximate Number of Stations Per MSA).''
Second, the first footnote contains some words (``within the ranges
shown in this table'') that were not part of the corresponding footnote
to the pre-existing Table 4. Therefore, the first footnote is revised
to read: ``Selection of urban areas and actual numbers of stations per
area will be jointly determined by EPA and the State Agency.''
Third, in paragraph (a) of section 4.6, the regulatory text notes
that State, and where applicable local, agencies must operate the
minimum number of required PM₁₀ SLAMS sites listed in Table
D-4 of appendix D. In the October 17, 2006, rulemaking, EPA intended to
retain all of the pre-existing regulatory text in the pre-existing
paragraph 3.7.1 (as last promulgated on July 18, 1997, at 62 FR 38850)
in new paragraph (a) of new section 4.6, to explain in words the
flexibility in minimum PM₁₀ monitoring requirements as
provided in the pre-existing Table 4 which had listed ranges of
required numbers (rather than a single number) of monitors for each of
the categories of MSA population and historical PM₁₀ range.
This regulatory text was inadvertently omitted. Therefore, EPA is
restoring the omitted text and correcting paragraph (a) of section 4.6
to read: ``Table D-4 indicates the approximate number of permanent
stations required in MSAs to characterize national and regional
PM₁₀ air quality trends and geographical patterns. The
number of PM₁₀ stations in areas where MSA populations
exceed 1,000,000 must be in the range from 2 to 10 stations, while in
low population urban areas, no more than 2 stations are required. A
range of monitoring stations is specified in Table D-4 because sources
of pollutants and local control efforts can vary from one part of the
country to another and, therefore, some flexibility is allowed in
selecting the actual number of stations in any one locale.''

F. Additional Regional Administrator Flexibility in Applying
PM₁₀ Minimum Monitoring Requirements

We are amending the monitoring rule to allow EPA Regional
Administrators to approve departures from the minimum number of
PM₁₀ monitors otherwise specified in the rule.
In the January 17, 2006, proposed monitoring rule (71 FR 2802), EPA
proposed minimum network design monitoring requirements for
PM_10-2.5. In paragraph (b) of section 4.8.1 of 40 CFR part
58, appendix D, (Network Design Criteria for Ambient Air Quality
Monitoring), EPA proposed that modifications from the
PM_10-2.5 monitoring requirements must be approved by the
Regional Administrator. The proposed regulatory language providing the
Regional Administrator flexibility to modify the PM_10-2.5
monitoring requirements was consistent with similar language proposed
for PM_2.5 that read: ``Deviations from these
PM_2.5 monitoring requirements must be approved by the EPA
Regional Administrator'' (71 FR 2801, paragraph (b) of section 4.7.1).
Similar regulatory language was proposed for ozone monitoring
requirements (71 FR 2798, paragraph (b) of section 4.1): ``Deviations
from the above O₃ requirements are allowed if approved by
the EPA Regional Administrator.'' The EPA finalized the Regional
Administrator authority to modify the PM_2.5 and ozone
monitoring requirements in the October 17, 2006, rule following a
public comment period in which no adverse comments were received about
the specific provisions concerning Regional Administrator flexibility
in applying these regulations.
The EPA did not adopt the proposed PM_10-2.5 minimum
monitoring network design including the Regional Administrator
flexibility language. The EPA notes, however, that no adverse comments
were received specifically addressing the proposed Regional
Administrator authority to modify PM_10-2.5 monitoring
network requirements although voluminous comment was received on other
proposed provisions of the PM_10-2.5 monitoring network
design and accompanying suitability test.
The EPA also proposed and adopted requirements for ``NCore''
multipollutant monitoring sites, including a provision allowing the
Administrator to approve modifications from these requirements. Again,
no adverse comment was received on this modification provision.
Finally, specific requirements in the rule for photochemical assessment
monitoring stations (PAMS) have always been modifiable by the Administrator.
Thus, EPA notes that under the current 40 CFR part 58, appendix D
network design requirements, PM₁₀ is the only pollutant with
minimum monitoring requirements not subject to modification based on
either Administrator or Regional Administrator evaluation and approval.
Such flexibility, already finalized for ozone and PM_2.5, can
prove useful in particular cases where a State demonstrates that meeting
the minimum monitoring requirements, for an individual MSA for example,
may be impractical or contrary to the optimum use of monitoring resources.
The EPA believes it is appropriate to allow the Regional
Administrator to modify PM₁₀ monitoring requirements, for
the same reasons such authority was finalized for PM_2.5 and
ozone monitoring requirements. Such authority allows for specific local
factors and information can be considered in order to make the
PM₁₀ monitoring network more economical while still meeting
program data needs. In light of the absence of any comments of concern
regarding very similar Administrator or Regional Administrator
authority for other pollutants, we do not expect any adverse comment on
this action. Therefore, EPA is amending paragraph

[[Page 32199]]

(a) of section 4.6 quoted in the section above and adding the following
sentence so it now reads: ``Modifications from these PM₁₀
monitoring requirements must be approved by the Regional
Administrator.'' See also section VI.E of this preamble for a
clarifying amendment which also affects section 4.6 of appendix D to
part 58 by restoring inadvertently omitted text.

G. Correction to Division Name and Address Reference

The October 17, 2006, final rule provided an address reference in
paragraph 2.4 of 40 CFR part 58 appendix A, to assist with
communications regarding the National Performance Evaluation Programs.
Monitoring agencies were advised to contact either the appropriate EPA
Regional Quality Assurance (QA) Coordinator at the appropriate EPA
Regional Office location, or the NPAP Coordinator, Emissions Monitoring
and Analysis Division (D205-02), U.S. Environmental Protection Agency,
Research Triangle Park, NC 27711. Due to a reorganization within the
Office of Air Quality Planning and Standards and subsequent physical
relocation within the North Carolina facility, the provided address
mail code (D205-02) is no longer correct for quality assurance related
communications. Additionally, the Emissions Monitoring and Analysis
Division has been renamed to the Air Quality Assessment Division, as
part of the same reorganization. Due to the possibility of future
address changes, EPA believes a more general reference to quality
assurance contact information is appropriate for inclusion in
regulatory language. Updated contact information for all air monitoring
program leads is maintained on the Ambient Monitoring Technology
Information Center (AMTIC) Web site http://www.epa.gov/ttn/amtic/
contacts.html. This website is well publicized and frequently accessed
by all monitoring agencies; therefore, specific address entries in the
rule are unnecessary and potentially misleading. Accordingly, EPA is
amending the regulatory text in paragraph 2.4 to read: ``For
clarification and to participate, monitoring organizations should
contact either the appropriate EPA Regional Quality Assurance (QA)
Coordinator at the appropriate EPA Regional Office location, or the
NPAP Coordinator at the Air Quality Assessment Division, Office of Air
Quality Planning and Standards, U.S. Environmental Protection Agency in
Research Triangle Park, North Carolina.''

H. Clarification to Conditions for Waiving Regional Administrator
Comment Period on Submitted Annual Monitoring Network Plans

The regulatory text in 40 CFR 58.10(a)(2) (71 FR 61298) describes
the approval process for State-submitted annual monitoring network
plans that propose SLAMS network modifications. Such plans are subject
to the approval of the Regional Administrator, including a new
requirement for the Regional Administrator to provide opportunity for
public comment during the 120-day period allowed for approval or
disapproval. The rule permits the Regional Administrator to waive the
separate public comment opportunity if the State or local agency has
already provided a public comment opportunity on its plan and has made
no changes to the plan subsequent to that comment opportunity.
Implied but not explicitly stated in the regulatory language is
that the Regional Administrator may forgo public comment only if the
State or local agency submitted the full text of public comments received
on its annual monitoring network plan to the Regional Administrator,
because only the availability of such detailed comments would make a
separate comment period by the Regional Administrator redundant.
The EPA believes that the aforementioned regulatory language should
be clarified to avoid ambiguity about what situations would require the
Regional Administrator to provide a public comment opportunity on
submitted annual monitoring network plans that contain SLAMS network
modifications. The EPA notes that the clarification does not modify the
minimum requirements for State and local agencies to make their plans
available for public inspection for at least 30 days prior to
submission to EPA.
Accordingly, the clarified regulatory text in the second sentence
of 40 CFR 58.10(a)(2) reads: ``If the State or local agency has already
provided a public comment opportunity on its plan and has made no
changes subsequent to that comment opportunity, and has submitted the
received comments together with the plan, the Regional Administrator is
not required to provide a separate opportunity for comment.''
Such comments could be transmitted to the Regional Administrator in
hard-copy or electronic format, and at a minimum, would include all
relevant information supplied to the State or local agency by the
commenters. Monitoring agencies would not be expected to provide
comment summaries or comment responses, although those submissions
could optionally be provided to the Regional Administrator in addition
to the actual text of the received comments.

I. Typographical Corrections

The Federal Register printing of the October 17, 2006, final rule
contained typographical errors in equations, tables, and figures. These
errors, as explained below and listed by Federal Register page
reference and CFR section number, are corrected in this rulemaking.
• 71 FR 61284. Subpart C of Part 53--Sec. 53.35(d)(4),
Calculation of mean concentrations. Equation 12: The ``n'' over the
summation symbol is replaced with ``m.''
• 71 FR 61284. Subpart C of Part 53--Sec. 53.35(e) and
Sec. 53.35(f), Tests for reference method and candidate method precision.
Equations 13 and 15: 100% is moved to be outside the square root symbol.
• 71 FR 61284. Subpart C of Part 53--Sec. 53.35(g), Test
for additive and multiplicative bias (comparative slope and intercept).
Equation 17: Left part of equation is changed to be R not R_j.
• 71 FR 61284. Subpart C of Part 53--Sec. 53.35(h), Tests
for comparison correlation. Equation 21: Radical sign in the
denominator is extended to cover both summation signs.
• 71 FR 61285. Table C-1 to Subpart C of Part 53, Test
Concentration Ranges, Number of Measurements Required, and Maximum
Discrepancy Specification. The four occurrences of ``Total'' in the
first column are moved to the second column.
• 71 FR 61285. Table C-1 to Subpart C of Part 53, Test
Concentration Ranges, Number of Measurements Required, and Maximum
Discrepancy Specification. Two entries of ``18'' are moved 3 columns
left to appear in the ``Second Set'' column rather than as shown in the
right-most column.
• 71 FR 61285. Table C-4 to Subpart C of Part 53--Test
Specifications for PM₁₀, PM_2.5 and
PM_10-2.5 Candidate Equivalent Methods. An erroneous ``R''
character in the table title is removed so that the title reads--Test
Specifications for PM₁₀, PM_2.5 and
PM_10-2.5 Candidate Equivalent Methods.
• 71 FR 61286. Table C-4 to Subpart C of Part 53--Test
Specifications for PM₁₀, PM_2.5 and PM_10-2.5
Candidate Equivalent Methods. In the column header for the last 2 columns,
the ``PM_10-2.5'' is corrected to be ``PM_10-2.5''.
• 71 FR 61286. Table C-4 to Subpart C of Part 53--Test Specifications
for PM₁₀, PM_2.5 and PM_10-2.5 Candidate

[[Page 32200]]

Equivalent Methods. The horizontal line under ``R_j > 60
µg/m3'' in the table is removed.
• 71 FR 61286. Table C-4 to Subpart C of Part 53--Test
Specifications for PM₁₀, PM_2.5 and
PM_10-2.5 Candidate Equivalent Methods. In the first column,
in the ``Precision of replicate reference method measurements * * *''
entry, the ``prime'' symbols are removed from ``RP_Rj'' and
``PM_10-2.5''.
• 71 FR 61286. Table C-4 to Subpart C of Part 53--Test
Specifications for PM₁₀, PM_2.5 and
PM_10-2.5 Candidate Equivalent Methods. An unintended period
is removed at the end of the entry in the last column, Intercept row,
and at the end of the second footnote.
• 71 FR 61286. Table C-4 to Subpart C of Part 53--Test
Specifications for PM₁₀, PM_2.5 and
PM_10-2.5 Candidate Equivalent Methods. Values for
correlation of reference method and candidate method measurements for
PM_2.5 Class II and III, and PM_10-2.5 Class II and
III are added to all four columns:

• >=0.93 for CCV<=0.4;
• >=0.85 + 0.2xCCV for 0.4<=CCV<=0.5;
• >=0.95 for CCV>=0.5.

• 71 FR 61287. Figure C-1 to Subpart C of Part 53--Suggested
Format for Reporting Test Results for Methods for SO₂, CO,
O₃, NO₂. Title and the first lines of content are
repositioned from being section text to being proper parts of Figure C-1.
• 71 FR 61287. Figures C-2 and C-3 to Subpart C of Part 53--
Illustration of the Slope and Intercept Limits for Class II and Class
III PM_2.5 Candidate Equivalent Methods and Illustration of
the Slope and Intercept Limits for Class II and Class III
PM_10-2.5 Candidate Equivalent Methods. ``PM_2.5''
is changed to ``PM_2.5,'' ``PM_10-2.5'' is changed
to ``PM_10-2.5,'' ``µg/m3'' is changed to ``µg/m\3\.''
Also, the ``Class II'' and ``Class III'' labels are related by arrows
to the outline of the hexagons rather than the area inside, to be
consistent with the title, which indicates ``Acceptance Limits.''
• 71 FR 61289. Figure C-4 to Subpart C of Part 53--
Illustration of the Minimum Limits for Correlation Coefficient for
PM_2.5 and PM_10-2.5 Class II and III methods. In
the axes labels, the commas are deleted and the ``r'' and the ``CCV''
are placed within parentheses.
• 71 FR 61293. Subpart E of Part 53--Sec. 53.58(g),
Operational field precision and blank test. Equation 26: the symbol
``C_1,j'' is corrected to ``C_i,j.''
• 71 FR 61294. Table E-1 to Subpart E of Part 53--Summary of
Test Requirements for Reference and Class I Equivalent Methods for
PM_2.5 and PM_10-2.5. In the 3rd column, row
identified as ``Sec. 53.56* * *,'' a comma is added after ``16.67
± 5%'' and before ``L/min.''
• 71 FR 61294. Table E-1 to Subpart E of Part 53--Summary of
Test Requirements for Reference and Class I Equivalent Methods for
PM_2.5 and PM_10-2.5. In the 3rd column, row
identified as ``Sec. 53.57* * *,'' one of the two periods at the end
of item 3 is removed.
• 71 FR 61294. Table E-1 to Subpart E of Part 53--Summary of
Test Requirements for Reference and Class I Equivalent Methods for
PM_2.5 and PM_10-2.5. In the fourth column, row
identified as ``Sec. 53.57* * *,'' item (c) is changed to read ``Solar
flux of 1000 ± 50 W/m\2\'' not ``Solar flux of 1000 ? 50 W/m\2\.''
• 71 FR 61294. Table E-1 to Subpart E of Part 53--Summary of
Test Requirements for Reference and Class I Equivalent Methods for
PM_2.5 and PM_10-2.5. Spurious ``?'' characters
throughout the table are removed.
• 71 FR 61294. Table E-1 to Subpart E of Part 53--Summary of
Test Requirements for Reference and Class I Equivalent Methods for
PM_2.5 and PM_10-2.5. Sec. 53.56 cell reference,
Barometric pressure effect test, Sample flow rate performance
specification, value is changed to be 16.67 (versus 16.6).
• 71 FR 61296. Table F-1 to Subpart F of Part 53--
Performance Specifications for PM_2.5 Class II Equivalent
Samplers. In the last column, row identified as ``Sec. 53.64,''
``Dp₅₀ = 2.5 µm ? 0.2 µm'' is changed to be
``Dp₅₀ = 2.5 µm ± 0.2 µm.''
• 71 FR 61296. Table F-1 to Subpart F of Part 53--
Performance Specifications for PM_2.5 Class II Equivalent
Samplers. In the last column, last row, a comma is added after
``0.15mg'' and before ``r >=0.97.''
• 71 FR 61296. Table F-1 to Subpart F of Part 53--
Performance Specifications for PM_2.5 Class II Equivalent
Samplers. Spurious ``?'' characters throughout the table are removed.
• 71 FR 61300. Figure 1 to Subpart B of Part 58--Ratio to
Standard for PM₁₀ Operating Schedule. A missing value (1.4)
is added on the X axis.
• 71 FR 61309. Appendix A of Part 58--Quality Assurance
Requirements for SLAMS, SPMs, and PSD Air Monitoring. Equation 7: A
missing ``'' character is added so that the equation reads:
Lower Probability Limit = m-1.96 • S.
• 71 FR 61309. Appendix A of Part 58--Quality Assurance
Requirements for SLAMS, SPMs, and PSD Air Monitoring. A missing minus
sign is added in caption below Equation 11 so that it reads: a chi-
squared distribution with n-1 degrees of freedom.
• 71 FR 61310. Appendix A of Part 58--Quality Assurance
Requirements for SLAMS, SPMs, and PSD Air Monitoring. Equation 12:
missing ellipsis is added in caption so that it reads: where,
n_j is the number of pairs and d₁, d₂,
* * * dn_j are the biases for each of the pairs to be averaged.
• ``PM_10C'', where it appears in Part 53 without
a subscripted ``C'', is replaced with ``PM_10c.''

VII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

Under Executive Order 12866 (58 FR 51735, October 4, 1993), this
action is a ``significant regulatory action'' because it may raise
novel legal policy issues arising out of legal mandates, the
President's priorities, or the principles set forth in the Executive
Order. Accordingly, EPA submitted this action to the Office of
Management and Budget (OMB) for review under Executive Order 12866 and
any changes made in response to OMB recommendations have been
documented in the docket for this action.

B. Paperwork Reduction Act

This action does not impose any new information collection, as it
only corrects printing errors, provides clarifications, and provides
new flexibility for PM₁₀ monitoring on a case-by-case basis.
However, the OMB has previously approved the information collection
requirements contained in the existing regulations for 40 CFR part 53
and 40 CFR part 58 under the provisions of the Paperwork Reduction Act,
44 U.S.C. 3501 et seq., and has assigned OMB control number 2060-0084,
EPA ICR number 0940.20. A copy of the OMB approved Information
Collection Request (ICR) may be obtained from Susan Auby, Collection
Strategies Division, U.S. Environmental Protection Agency (2822T), 1200
Pennsylvania Ave., NW., Washington, DC 20460 or by calling (202) 566-
1672. This action does not impose any new information collection burden
beyond the already-approved ICR.
Burden means the total time, effort, or financial resources
expended by persons to generate, maintain, retain, or disclose or
provide information to or for a Federal agency. This includes the time
needed to review instructions; develop, acquire, install, and utilize
technology and systems for the purposes of collecting, validating, and
verifying

[[Page 32201]]

information, processing and maintaining information, and disclosing and
providing information; adjust the existing ways to comply with any
previously applicable instructions and requirements; train personnel to
be able to respond to a collection of information; search data sources;
complete and review the collection of information; and transmit or
otherwise disclose the information. An agency may not conduct or
sponsor, and a person is not required to respond to a collection of
information unless it displays a currently valid OMB control number.
The OMB control numbers for EPA's regulations in 40 CFR are listed in
40 CFR part 9.

C. Regulatory Flexibility Act

The Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedure Act or any other statute unless the agency certifies that the
rule will not have a significant economic impact on a substantial
number of small entities. Small entities include small businesses,
small organizations, and small governmental jurisdictions.
For purposes of assessing the impacts of today's rule on small
entities, small entity is defined as: (1) A small business defined by
the Small Business Administration's (SBA) regulations at 13 CFR
121.201; (2) a small governmental jurisdiction that is a government of
a city, county, town, school district or special district with a
population of less than 50,000; and (3) a small organization that is
any not-for-profit enterprise which is independently owned and operated
and is not dominant in its field.
After considering the economic impacts of today's final rule on
small entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities.
This final rule will not impose any requirements on small entities.
None of the corrections and clarifications creates additional
regulatory requirements on affected entities compared to those that
were promulgated in the final rule that was published in the Federal
Register on October 17, 2006. The rule changes being made only correct
printing errors, provide clarifications, and provides new flexibility
for PM₁₀ monitoring on a case-by-case basis.

D. Unfunded Mandates Reform Act

Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public
Law 104-4, establishes requirements for Federal agencies to assess the
effects of their regulatory actions on State, local, and tribal
governments and the private sector. Under section 202 of the UMRA, EPA
generally must prepare a written statement, including a cost-benefit
analysis, for proposed and final rules with ``Federal mandates'' that
may result in expenditures to State, local, and Tribal governments, in
the aggregate, or to the private sector, of $100 million or more in any
one year. Before promulgating an EPA rule for which a written statement
is needed, section 205 of the UMRA generally requires EPA to identify
and consider a reasonable number of regulatory alternatives and adopt
the least costly, most cost-effective or least burdensome alternative
that achieves the objectives of the rule. The provisions of section 205
do not apply when they are inconsistent with applicable law. Moreover,
section 205 allows EPA to adopt an alternative other than the least
costly, most cost-effective or least burdensome alternative if the
Administrator publishes with the final rule an explanation why that
alternative was not adopted. Before EPA establishes any regulatory
requirements that may significantly or uniquely affect small
governments, including Tribal governments, it must have developed under
section 203 of the UMRA a small government agency plan. The plan must
provide for notifying potentially affected small governments, enabling
officials of affected small governments to have meaningful and timely
input in the development of EPA regulatory proposals with significant
Federal intergovernmental mandates, and informing, educating, and
advising small governments on compliance with the regulatory requirements.
The EPA has determined that this final rule does not contain a
Federal mandate that may result in expenditures of $100 million or more
for State, local, and tribal governments, in the aggregate, or the
private sector in any one year, because the changes being made are
merely clarifications and corrections. Thus, today's rule is not
subject to the requirements of sections 202 and 205 of the UMRA.
The EPA has determined that this final rule contains no regulatory
requirements that might significantly or uniquely affect small
governments. None of the changes creates additional regulatory
requirements on affected entities compared to those that were
promulgated in the final rule that was published in the Federal
Register on October 17, 2006. The rule changes being made only correct
printing errors, provide clarifications, and provide some new
flexibility for PM₁₀ monitoring on a case-by-case basis.
Therefore, this final rule is not subject to the requirements of
section 203 of the UMRA.

E. Executive Order 13132: Federalism

Executive Order 13132 (64 FR 43255, August 10, 1999), requires EPA
to develop an accountable process to ensure ``meaningful and timely
input by State and local officials in the development of regulatory
policies that have federalism implications.'' ``Policies that have
federalism implications'' is defined in the Executive Order to include
regulations that have ``substantial direct effects on the States, on
the relationship between the national government and the States, or on
the distribution of power and responsibilities among the various levels
of government.''
This final rule does not have federalism implications because it
will not have substantial direct effects on the States, on the
relationship between the national government and the States, or on the
distribution of power and responsibilities among the various levels of
government, as specified in Executive Order 13132. This is because the
changes being made only correct printing errors, provide
clarifications, and provides some new flexibility for PM₁₀
monitoring on a case-by-case basis. Thus, Executive Order 13132 does
not apply to this final rule.

F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments

Executive Order 13175, entitled ``Consultation and Coordination
with Indian Tribal Governments'' (59 FR 22951, November 9, 2000),
requires EPA to develop an accountable process to ensure ``meaningful
and timely input by tribal officials in the development of regulatory
policies that have tribal implications.'' This final rule does not have
tribal implications, as specified in Executive Order 13175. The EPA
consulted with tribal officials early in the process of developing the
October 17, 2006, rule to permit them to have meaningful and timely
input into its development. Although tribal governments may elect to
conduct ambient air monitoring, none of the changes in today's rule
apply directly to tribal governments. Thus, Executive Order 13175 does
not apply to this rule.

G. Executive Order 13045: Protection of Children From Environmental
Health and Safety Risks

Executive Order 13045 ``Protection of Children from Environmental
Health Risks and Safety Risks'' (62 FR 19885,

[[Page 32202]]

April 23, 1997) applies to any rule that: (1) Is determined to be
``economically significant'' as defined under EO 12866, and (2)
concerns an environmental health or safety risk that EPA has reason to
believe may have a disproportionate effect on children. If the
regulatory action meets both criteria, the Agency must evaluate the
environmental health or safety effects of the planned rule on children,
and explain why the planned regulation is preferable to other
potentially effective and reasonably feasible alternatives considered
by the Agency.
EPA interprets EO 13045 as applying only to those regulatory
actions that concern health or safety risks, such that the analysis
required under section 5-501 of the EO has the potential to influence
the regulation. This final rule is not subject to EO 13045 because it
does not establish an environmental standard intended to mitigate
health or safety risks.

H. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations

Executive Order 12898 (59 FR 7629, February 16, 1994) establishes
federal executive policy on environmental justice. Its main provision
directs Federal agencies, to the greatest extent practicable and
permitted by law, to make environmental justice part of their mission
by identifying and addressing, as appropriate, disproportionately high
and adverse human health or environmental effects of their programs,
policies, and activities on minority populations and low-income
populations in the United States.
EPA has determined that this final rule will not have
disproportionately high and adverse human health or environmental
effects on minority or low-income populations because it does not
affect the level of protection provided to human health or the
environment. The rule merely amends the October 17, 2006, final
monitoring rule (71 FR 61236) by correcting printing errors, providing
clarifications, and providing some new flexibility for PM₁₀
monitoring on a case-by-case basis.

I. Executive Order 13211: Actions That Significantly Affect Energy
Supply, Distribution, or Use

This rule is not a ``significant energy action'' as defined in
Executive Order 13211, ``Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution or Use'' (66 FR 28355,
May 22, 2001) because it is not likely to have a significant adverse
effect on the supply, distribution, or use of energy. No significant
change in the use of energy is expected because the total number of
monitors for ambient air quality measurements will not increase above
present levels. Further, we have concluded that this rule is not likely
to have any adverse energy effects.

J. National Technology Transfer Advancement Act

Section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (``NTTAA''), Public Law No. 104-113, 12(d) (15 U.S.C. 272
note) directs EPA to use voluntary consensus standards in its
regulatory activities unless to do so would be inconsistent with
applicable law or otherwise impractical. Voluntary consensus standards
are technical standards (e.g., materials specifications, test methods,
sampling procedures, and business practices) that are developed or
adopted by voluntary consensus standards bodies. The NTTAA directs EPA
to provide Congress, through OMB, explanations when the Agency decides
not to use available and applicable voluntary consensus standards.
This action does not involve technical standards, other than to
make corrections and clarifications. Therefore, EPA did not consider
the use of any voluntary consensus standards.

K. Congressional Review Act

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 Congress and to the Comptroller General
of the United States. EPA will submit a report containing this rule 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 ``major rule'' as defined by 5 U.S.C.
804(2). This final rule will not have an annual effect on the economy
of $100 million or more, will not result in a major increase in costs
or prices for State or local agencies, and will not affect competition
with foreign-based enterprises in domestic and export markets. The
final amendments will be effective on September 10, 2007.

List of Subjects in 40 CFR Parts 53 and 58

Environmental protection, Administrative practice and procedure,
Air pollution control, Intergovernmental relations, Reporting and
recordkeeping requirements.

Dated: April 30, 2007.
Stephen L. Johnson,
Administrator.

• For the reasons stated in the preamble, title 40, chapter I, parts 53
and 58 of the Code of Federal Regulations are amended as follows:

PART 53--[AMENDED]

• 1. The authority citation for part 53 continues to read as follows:

Authority: Section 301(a) of the Clean Air Act (42 U.S.C. sec.
1857g(a)), as amended by sec. 15(c)(2) of Pub. L. 91-604, 84 Stat.
1713, unless otherwise noted.

Subpart C--[Amended]

• 2. Section 53.35 is amended by:
• a. Revising Equation 12 of paragraph (d)(4),
• b. Revising Equation 13 of paragraph (e)(1),
• c. Revising Equation 15 of paragraph (f)(1),
• d. Revising Equation 17 of paragraph (g)(1), and
• e. Revising Equation 21 of paragraph (h)(1) to read as follows:

Sec. 53.35 Test procedure for Class II and Class III methods for PM
2.5 and PM10-2.5.

* * * * *
(d) * * *
(4) * * *
[GRAPHIC]
[TIFF OMITTED] TR41AD07.000

Where:

C_j = The mean concentration measured by the candidate
method for the measurement set;
C_i,j = The measurement of the candidate method sampler or
analyzer i on test day j; and
m = The number of valid candidate method measurements in the
measurement set (normally 3).

(e) * * *
(1) * * *

[[Page 32203]]
[GRAPHIC]
[TIFF OMITTED] TR41AD07.001

* * * * *
(f) * * *
(1) * * *
[GRAPHIC]
[TIFF OMITTED] TR41AD07.002

* * * * *
(g) * * *
(1) * * *
[GRAPHIC]
[TIFF OMITTED] TR41AD07.003

* * * * *
(h) * * *
(1) * * *
[GRAPHIC]
[TIFF OMITTED] TR41AD07.004

* * * * *

• 3. Table C-1 to subpart C is revised to read as follows:

Table C-1 to Subpart C of Part 53--Test Concentration Ranges, Number of Measurements Required, and Maximum
Discrepancy Specification
----------------------------------------------------------------------------------------------------------------
Simultaneous measurements required
-------------------------------------------- Maximum
Concentration 1-hr 24-hr discrepancy
Pollutant range, parts per -------------------------------------------- specification,
million Second Second parts per
First set set First set set million
----------------------------------------------------------------------------------------------------------------
Ozone........................... Low 0.06 to 0.10.. 5 6 ......... ......... 0.02
Med 0.15 to 0.25.. 5 6 ......... ......... .03
High 0.35 to 0.45. 4 6 ......... ......... .04
-----------------------------------------------------------
Total............. 14 18 ......... ......... ..............
-----------------------------------------------------------
Carbon monoxide................. Low 7 to 11....... 5 6 ......... ......... 1.5
Med 20 to 30...... 5 6 ......... ......... 2.0
High 35 to 45..... 4 6 ......... ......... 3.0
-----------------------------------------------------------
Total............. 14 18 ......... ......... ..............
-----------------------------------------------------------
Sulfur dioxide.................. Low 0.02 to 0.05.. ......... ......... 3 3 0.02
Med 0.10 to 0.15.. ......... ......... 2 3 .03
High 0.30 to 0.50. 7 8 2 2 .04
-----------------------------------------------------------
Total............. 7 8 7 8 ..............
-----------------------------------------------------------
Nitrogen dioxide................ Low 0.02 to 0.08.. ......... ......... 3 3 0.02
Med 0.10 to 0.20.. ......... ......... 2 3 .03
High 0.25 to 0.35. ......... ......... 2 2 .03
-----------------------------------------------------------
Total............. ......... ......... 7 8 ..............
----------------------------------------------------------------------------------------------------------------

• 4. Table C-4 to subpart C is revised to read as follows:

Table C-4 to Subpart C of Part 53.--Test Specifications for PM10, PM2.5 and PM10 2.5 Candidate Equivalent Methods
--------------------------------------------------------------------------------------------------------------------------------------------------------
PM2.5 PM10 2.5
Specification PM10 -------------------------------------------------------------------------------------------------
Class I Class II Class III Class II Class III
--------------------------------------------------------------------------------------------------------------------------------------------------------
Acceptable concentration range 15-300................ 3-200............ 3-200 3-200 3-200 3-200
(Rj), µg/m3.
Minimum number of test sites.. 2..................... 1................ 2 4 2 4

[[Page 32204]]

Minimum number of candidate 3..................... 3................ 3 \1\ 3 \1\ 3 \1\ 3 \1\
method samplers or analyzers
per site.
Number of reference method 3..................... 3................ 3 \1\ 3 \1\ 3 \1\ 3 \1\
samplers per site.
Minimum number of acceptable
sample sets per site for PM10
methods:
Rj < 60 µg/m3.......... 3
Rj > 60 µg/m3.......... 3
Total..................... 10
Minimum number of acceptable
sample sets per site for
PM2.5 and PM10-2.5 candidate
equivalent methods:
Rj < 30 µg/m3 for 24-hr ...................... 3
or Rj < 20 µg/m3 for
48-hr samples.
Rj > 30 µg/m3 for 24-hr ...................... 3
or Rj > 20 µg/m3 for
48-hr samples.
Each season............... ...................... 10............... 23 23 23 23
Total, each site.......... ...................... 10............... 23 23 (46 for two- 23 23 (46 for two-
season sites) season sites)
Precision of replicate 5 µg/m3 or 7%...... 2 µg/m3 or 5%. 10% 2 10% 2 10% 2 10% 2
reference method
measurements, PRj or RPRj,
respectively; RP for Class II
or III PM2.5 or PM10-2.5,
maximum.
Precision of PM2.5 or PM10-2.5 ...................... ................. 10% 2 15% 2 15% 2 15% 2
candidate method, CP, each
site.
Slope of regression 1 ± 0.10... 1 ± 1 ± 1 ± 1 ± 1 ±
relationship.. 0.05. 0.10 0.10 0.10 0.12
Intercept of regression 0 ± 5...... 0 ± 1. Between: 13.55 - Between: 15.05 - Between: 62.05 - Between: 70.50 -
relationship, µg/m3. (15.05 x slope), (17.32 x slope), (70.5 x slope), (82.93 x slope),
but not less than but not less than but not less than but not less
-1.5; and 16.56 - -2.0; and 15.05 - -3.5; and 78.95 - than -7.0; and
(15.05 x slope), (13.20 x slope), (70.5 x slope), 70.50 - (61.16 x
but not more than but not more than but not more than slope), but not
+1.5 +2.0 +3.5 more than +7.0
-------------------------------------------------------------------------------------------------------------------------
Correlation of reference >= 0.97............... >= 0.97.......... >= 0.93--for CCV <= 0.4; >= 0.85 + 0.2 x CCV--for 0.4 <= CCV <= 0.5; >= 0.95--
method and candidate method for CCV >= 0.5
measurements.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Some missing daily measurement values may be permitted; see test procedure.
\2\ Calculated as the root mean square over all measurement sets.

• 5. Figures C-1 through C-4 to subpart C are revised to read as follows:

Figure C-1 to Subpart C of Part 53--Suggested Format for Reporting
Test Results for Methods for SO 2, CO, O 3, NO 2

Candidate Method-------------------------------------------------------

Reference Method-------------------------------------------------------

Applicant--------------------------------------------------------------

□ First Set □ Second Set □ Type □ 1 Hour □ 24 Hour

[[Page 32205]]

--------------------------------------------------------------------------------------------------------------------------------------------------------
Concentration, ppm
Concentration range Date Time -------------------------------- Difference Table C-1 Pass or fail
Candidate Reference spec.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low 1
------------------------------------------------------------------------------------------------------------------------
-------- ppm 2
------------------------------------------------------------------------------------------------------------------------
to -------- ppm 3
------------------------------------------------------------------------------------------------------------------------
4
------------------------------------------------------------------------------------------------------------------------
5
------------------------------------------------------------------------------------------------------------------------
6
--------------------------------------------------------------------------------------------------------------------------------------------------------
Medium 1
------------------------------------------------------------------------------------------------------------------------
-------- ppm 2
------------------------------------------------------------------------------------------------------------------------
to -------- ppm 3
------------------------------------------------------------------------------------------------------------------------
4
------------------------------------------------------------------------------------------------------------------------
5
------------------------------------------------------------------------------------------------------------------------
6
--------------------------------------------------------------------------------------------------------------------------------------------------------
High 1
------------------------------------------------------------------------------------------------------------------------
-------- ppm 2
------------------------------------------------------------------------------------------------------------------------
to -------- ppm 3
------------------------------------------------------------------------------------------------------------------------
4
------------------------------------------------------------------------------------------------------------------------
5
------------------------------------------------------------------------------------------------------------------------
6
------------------------------------------------------------------------------------------------------------------------
7
------------------------------------------------------------------------------------------------------------------------
8
--------------------------------------------------------------------------------------------------------------------------------------------------------
....... .............. .............. .............. .............. .............. Total
Failures:
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 32206]]
[GRAPHIC]
[TIFF OMITTED] TR41AD07.009
[[Page 32207]]
[GRAPHIC]
[TIFF OMITTED] TR41AD07.010
[[Page 32208]]
[GRAPHIC]
[TIFF OMITTED] TR41AD07.011

Subpart E--[Amended]

• 6. Section 53.58 is amended by revising Equation 26 of paragraph
(g)(2)(i) to read as follows:

Sec. 53.58 Operational field precision and blank test.

* * * * *
(g) * * *
(2)(i) * * *
[GRAPHIC]
[TIFF OMITTED] TR41AD07.005

* * * * *
• 7. Table E-1 to subpart E is revised to read as follows:

Table E-1 to Subpart E of Part 53.--Summary of Test Requirements for Reference and Class I Equivalent Methods
for PM2.5 and PM10 2.5
----------------------------------------------------------------------------------------------------------------
Performance Part 50, appendix
Subpart E procedure Performance test specification Test conditions L reference
----------------------------------------------------------------------------------------------------------------
Sec. 53.52 Sample leak check Sampler leak check External leakage: Controlled leak Sec. 7.4.6.
test. facility. 80 mL/min, max. flow rate of 80
Internal leakage: mL/ min.
80 mL/min, max.
----------------------------------------------------------------------------------------------------------------
Sec. 53.53 Base flow rate test Sample flow rate.. 1. 16.67 (a) 6-hour normal Sec. 7.4.1.
1. Mean........... ±5%, L/ min. operational test Sec. 7.4.2.
2. Regulation..... 2. 2%, max........ plus flow rate Sec. 7.4.3.
3. Meas accuracy.. 3. 2%, max........ cut-off test. Sec. 7.4.4.
4. CV accuracy.... 4. 0.3% max....... (b) Normal Sec. 7.4.5.
5. Cut-off........ 5. Flow rate cut- conditions.
off if flow rate (c) Additional 55
deviates more mm Hg pressure
than 10% from drop to simulate
design flow rate loaded filter.
±60 (d) Variable flow
minus> 30 seconds. restriction used
for cut-off test.

[[Page 32209]]

Sec. 53.54 Power interruption Sample flow rate.. 1. 16.67 (a) 6-hour normal Sec. 7.4.1.
test. 1. Mean........... ± 5%, L/ min. operational test. Sec. 7.4.2.
2. Regulation..... 2. 2%, max........ (b) Nominal Sec. 7.4.3.
3. Meas. accuracy. 3. 2%, max........ conditions. Sec. 7.4.5.
4. CV accuracy.... 4. 0.3% max....... (c) Additional 55 Sec. 7.4.12.
5. Occurrence time 5. ± 2 mm Hg pressure Sec. 7.4.13.
of power min if >60 drop to simulate Sec. 7.4.15.4.
interruptions. seconds.. loaded filter. Sec. 7.4.15.5.
6. Elapsed sample 6. ± 20 (d) 6 power
time. seconds. interruptions of
7. Sample volume.. 7. ± various durations.
2%, max.
----------------------------------------------------------------------------------------------------------------
Sec. 53.55 Temperature and Sample flow rate.. 1. 16.67 (a) 6-hour normal Sec. 7.4.1.
line voltage test. 1. Mean........... ± 5%, L/ min. operational test. Sec. 7.4.2.
2. Regulation..... 2. 2%, max........ (b) Normal Sec. 7.4.3.
3. Meas. accuracy. 3. 2%, max........ conditions. Sec. 7.4.5.
4. CV accuracy.... 4. 0.3% max....... (c) Additional 55 Sec. 7.4.8.
5. Temperature 5. 2 [deg]C....... mm Hg pressure Sec. 7.4.15.1.
meas. accuracy. drop to simulate
6. Proper loaded filter.
operation.. (d) Ambient
temperature at -
20 and +40 [deg]C.
(e) Line voltage:
105 Vac to 125
Vac.
----------------------------------------------------------------------------------------------------------------
Sec. 53.56 Barometric pressure Sample flow rate.. 1. 16.67 (a) 6-hour normal Sec. 7.4.1.
effect test. 1. Mean........... ± 5%, L/ min. operational test. Sec. 7.4.2.
2. Regulation..... 2. 2%, max........ (b) Normal Sec. 7.4.3.
3. Meas. accuracy. 3. 2%, max........ conditions. Sec. 7.4.5.
4. CV accuracy.... 4. 0.3% max....... (c) Additional 55 Sec. 7.4.9.
5. Pressure meas. 5. 10 mm Hg....... mm Hg pressure
accuracy. drop to simulate
6. Proper loaded filter.
operation.. (d) Barometric
pressure at 600
and 800 mm Hg.
----------------------------------------------------------------------------------------------------------------
Sec. 53.57 Filter temperature 1. Filter temp. 1. 2 [deg]C....... (a) 4-hour Sec. 7.4.8.
control test. meas. accuracy. 2. 2 [deg]C....... simulated solar Sec. 7.4.10.
2. Ambient temp. 3. Not more than 5 radiation, Sec. 7.4.11.
meas. accuracy. [deg]C above sampling.
3. Filter temp. ambient temp. for (b) 4-hour
control accuracy, more than 30 min. simulated solar
sampling and non- radiation, non-
sampling. sampling.
(c) Solar flux of
1000 ±
50 W/m 2.
----------------------------------------------------------------------------------------------------------------
Sec. 53.58 Field precision 1. Measurement 1. Pj < 2 µg/m3 (a) 3 collocated Sec. 5.1.
test. precision. or RPj < 5%. samplers at 1 Sec. 7.3.5.
2. Storage 2. 50 µg max. site for at least Sec. 8.
deposition test average weight 10 days. Sec. 9.
for sequential gain/blank filter. (b) PM2.5 conc. > Sec. 10.
samplers. 3 µg/m3.
(c) 24- or 48-hour
samples.
(d) 5- or 10-day
storage period
for inactive
stored filters.
----------------------------------------------------------------------------------------------------------------
The Following Requirement Is Applicable to Class I Candidate Equivalent Methods Only
----------------------------------------------------------------------------------------------------------------
Sec. 53.59 Aerosol transport Aerosol transport. 97%, min. for all Determine aerosol
test. channels.. transport through
any new or
modified
components with
respect to the
reference method
sampler before
the filter for
each channel.
----------------------------------------------------------------------------------------------------------------

Subpart F--[Amended]

• 8. Table F-1 to subpart F is revised to read as follows:

[[Page 32210]]

Table F-1 to Subpart F of Part 53.--Performance Specifications for PM2.5
Class II Equivalent Samplers
------------------------------------------------------------------------
Performance test Specifications Acceptance criteria
------------------------------------------------------------------------
Sec. 53.62 Full Wind Solid VOAG produced Dp50 = 2.5 µm
Tunnel Evaluation. aerosol at 2 km/hr ± 0.2
and 24 km/hr. µm Numerical
Analysis Results:
95% < = Rc < = 105%.
Sec. 53.63 Wind Tunnel Liquid VOAG produced Relative Aspiration:
Inlet Aspiration Test. aerosol at 2 km/hr 95% < = A < = 105%.
and 24 km/hr.
Sec. 53.64 Static Evaluation of the Dp50 = 2.5 µm
Fractionator Test. fractionator under ± 0.2
static conditions. µm Numerical
Analysis Results:
95% < = Rc < = 105%.
Sec. 53.65 Loading Test... Loading of the clean Acceptance criteria
candidate under as specified in the
laboratory post-loading
conditions. evaluation test
(Sec. 53.62, Sec.
53.63, or Sec.
53.64).
Sec. 53.66 Volatility Test Polydisperse liquid Regression
aerosol produced by Parameters Slope =
air nebulization of 1 ± 0.1,
A.C.S. reagent Intercept = 0
grade glycerol, ± 0.15 mg, r
99.5% minimum >= 0.97.
purity.
------------------------------------------------------------------------

PART 58--[AMENDED]

• 9. The authority citation for part 58 continues to read as follows:

Authority: 42 U.S.C. 7403, 7410, 7601(a), 7611, and 7619.

Subpart B--[Amended]

• 10. Section 58.10 is amended by revising the second sentence in
paragraph (a)(2) to read as follow:

Sec. 58.10 Annual monitoring network plan and periodic network
assessment.

(a)(1) * * *
(2) * * * If the State or local agency has already provided a
public comment opportunity on its plan and has made no changes
subsequent to that comment opportunity, and has submitted the received
comments together with the plan, the Regional Administrator is not
required to provide a separate opportunity for comment.
* * * * *

• 11. Section 58.12 is amended by revising paragraph (d)(1), paragraph
(d)(3), and the first sentence of paragraph (e) to read as follows:

Sec. 58.12 Operating schedules.

* * * * *
(d) * * *
(1)(i) Manual PM_2.5 samplers at required SLAMS stations
without a collocated continuously operating PM_2.5 monitor
must operate on at least a 1-in-3 day schedule.
(ii) For SLAMS PM_2.5 sites with both manual and
continuous PM_2.5 monitors operating, the monitoring agency
may request approval for a reduction to 1-in-6 day PM_2.5
sampling or for seasonal sampling from the EPA Regional Administrator.
The EPA Regional Administrator may grant sampling frequency reductions
after consideration of factors, including but not limited to the
historical PM_2.5 data quality assessments, the location of
current PM_2.5 design value sites, and their regulatory data
needs. Required SLAMS stations whose measurements determine the design
value for their area and that are within plus or minus 10 percent of
the NAAQS; and all required sites where one or more 24-hour values have
exceeded the NAAQS each year for a consecutive period of at least 3
years are required to maintain at least a 1-in-3 day sampling
frequency. A continuously operating FEM or ARM PM_2.5 monitor
satisfies this requirement.
(iii) Required SLAMS stations whose measurements determine the
design value for their area and that are within plus or minus 5 percent
of the daily PM_2.5 NAAQS must have an FRM or FEM operate on
a daily schedule. A continuously operating FEM or ARM PM_2.5
monitor satisfies this requirement.
* * * * *
(3) Manual PM_2.5 speciation samplers at STN stations
must operate on at least a 1-in-3 day sampling frequency.
(e) For PM₁₀ samplers, a 24-hour sample must be taken
from midnight to midnight (local standard time) to ensure national
consistency. * * *

Sec. 58.12 [Amended]

• 12. Figure 1 of paragraph (e) of Sec. 58.12 is revised to read as
follows:

Subpart C--[Amended]

• 13. Section 58.20(c) is revised to read as follows:

Sec. 58.20 Special purpose monitors (SPM).

* * * * *

[[Page 32211]]
[GRAPHIC]
[TIFF OMITTED] TR41AD07.012

(c) All data from an SPM using an FRM, FEM, or ARM which has
operated for more than 24 months is eligible for comparison to the
relevant NAAQS, subject to the conditions of Sec. 58.30, unless the
air monitoring agency demonstrates that the data came from a particular
period during which the requirements of appendix A, appendix C, or
appendix E to this part were not met in practice.
* * * * *

Appendix A to Part 58--[Amended]

• 14. Appendix A is amended by:
• a. Revising the third (last) sentence of section 2.4;
• b. Revising Equation 7 of section 4.1.4;
• c. Revising the definition of the symbol ``n'' for Equation 11 of
section 4.2.1,
• d. Revising the last sentence in section 4.2.2.2, and
• e. Revising the definition of the symbol ``n_j'' for Equation
12 of section 4.3.2.1 to read as follows:

2. General Monitoring Requirements

* * * * *
2.4 * * * For clarification and to participate, monitoring
organizations should contact either the appropriate EPA Regional
Quality Assurance (QA) Coordinator at the appropriate EPA Regional
Office location, or the NPAP Coordinator at the Air Quality
Assessment Division, Office of Air Quality Planning and Standards,
U.S. Environmental Protection Agency in Research Triangle Park,
North Carolina.
* * * * *

4. Calculations for Data Quality Assessments

* * * * *
4.1.4 * * *
[GRAPHIC]
[TIFF OMITTED] TR41AD07.006

* * * * *
4.2.1 * * *
[GRAPHIC]
[TIFF OMITTED] TR41AD07.007

where, n is the number of valid data pairs being aggregated, and
X2 _{0.1, n-1} is the 10th percentile of a chi-
squared distribution with n-1 degrees of freedom. The factor of 2 in
the denominator adjusts for the fact that each d_i is
calculated from two values with error.

4.2.2 * * * The absolute volume bias upper bound is then
calculated using equation 3 of this appendix, where n is the number
of flow rate audits being aggregated; t_{0.95, n-1} is the
95th quantile of a t-distribution with n-1 degrees of freedom, the
quantity AB is the mean of the absolute values of the
d_i's and is calculated using equation 4 of this appendix,
and the quantity AS in equation 3 of this appendix is the standard
deviation of the absolute values of the d_i's and is
calculated using equation 5 of this appendix.
4.3.2.1 * * *
[GRAPHIC]
[TIFF OMITTED] TR41AD07.008

where, nj is the number of pairs and d1, d₂, * * *,
dnj are the biases for each of the pairs to be averaged.
* * * * *

Appendix D to Part 58--[Amended]

• 15. Appendix D is amended by:
• a. Revising section 4.6(a);
• b. Revising the title of Table D-4 and Footnote 1 to Table D-4; and
• c. Revising section 4.7.2 to read as follows:

4. Pollutant-Specific Design Criteria for SLAMS Sites

* * * * *
4.6 Particulate Matter (PM₁₀) Design Criteria.
(a) Table D-4 indicates the approximate number of permanent
stations required in MSAs to characterize national and regional
PM₁₀ air quality trends and geographical patterns. The
number of PM₁₀ stations in areas where MSA populations
exceed 1,000,000 must be in the range from 2 to 10 stations, while
in low population urban areas, no more than two stations are
required. A range of monitoring stations is specified in Table D-4
because sources of pollutants and local control efforts can vary
from one part of the country to another and therefore, some
flexibility is allowed in selecting the actual number of stations in
any one locale. Modifications from these PM₁₀ monitoring
requirements must be approved by the Regional Administrator.

Table D-4 of Appendix D to Part 58. PM₁₀ Minimum Monitoring
Requirements (Approximate Number of Stations Per MSA) \1\

* * * * *
---------------------------------------------------------------------------

\1\ Selection of urban areas and actual numbers of stations per
area will be jointly determined by EPA and the State agency.
---------------------------------------------------------------------------

4.7.2 Requirement for Continuous PM_2.5 Monitoring.
The State, or where appropriate, local agencies must operate
continuous PM_2.5 analyzers equal to at least one-half
(round up) the minimum required sites listed in Table D-5 of this
appendix. At least one required continuous analyzer in each MSA must
be collocated with one of the required FRM/FEM/ARM monitors, unless
at least one of the required FRM/FEM/ARM monitors is itself a
continuous FEM or ARM monitor in

[[Page 32212]]

which case no collocation requirement applies. State and local air
monitoring agencies must use methodologies and quality assurance/
quality control (QA/QC) procedures approved by the EPA Regional
Administrator for these required continuous analyzers.
* * * * *
[FR Doc. 07-2201 Filed 6-11-07; 8:45 am]
BILLING CODE 6560-50-P

Notices For
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
1994

Ambient Air Monitoring Regulations: Correcting and Other Amendments

Local Navigation