[Federal Register Volume 79, Number 176 (Thursday, September 11, 2014)]
[Proposed Rules]
[Pages 54355-54395]
[FR Doc No: 2014-19758]

Vol. 79

Thursday,

No. 176

September 11, 2014

Part II

Environmental Protection Agency

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40 CFR Part 58

Revisions to Ambient Monitoring Quality Assurance and Other
Requirements; Proposed Rule

Federal Register / Vol. 79 , No. 176 / Thursday, September 11, 2014 /
Proposed Rules

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 58

 [EPA-HQ-OAR-2013-0619; FRL-9915-16-OAR]
RIN 2060-AR59

Revisions to Ambient Monitoring Quality Assurance and Other
Requirements

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: This action proposes revisions to ambient air monitoring
requirements for criteria pollutants to provide clarifications to
existing requirements to reduce the compliance burden of monitoring
agencies operating ambient networks. This proposal focuses on
reorganizing and clarifying quality assurance requirements, simplifying
and reducing data reporting and certification requirements, clarifying
the annual monitoring network plan public notice requirements, revising
certain network design criteria for nonsource lead monitoring, and
addressing other issues in part 58 Ambient Air Quality Surveillance
Requirements.

DATES: Comments must be received on or before November 10, 2014.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2013-0619, by one of the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov.
Follow the online instructions for submitting comments.
     Email<EMAIL_ADDRESS>Include docket ID No. EPA-
HQ-OAR-2013-0619 in the subject line of the message.
     Fax:<PHONE_NUMBER>
     Mail: Environmental Protection Agency, Mail code 28221T,
Attention Docket No. EPA-HQ-OAR-2013-0619, 1200 Pennsylvania Ave. NW.,
Washington, DC 20460. Please include a total of two copies.
     Hand/Courier Delivery: EPA Docket Center, Room 3334, EPA
WJC West Building, 1301 Constitution Ave. NW., 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-
2013-0619. 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 email. The www.regulations.gov Web site is an
``anonymous access'' system, which means the EPA will not know your
identity or contact information unless you provide it in the body of
your comment. If you send an email comment directly to the EPA without
going through http://www.regulations.gov, your email 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, the 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 the EPA cannot read your comment due
to technical difficulties and cannot contact you for clarification, the
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. For additional information about the
EPA's public docket, visit the EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.
    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 www.regulations.gov or in hard copy at the Air and Radiation Docket
and Information Center, EPA/DC, Room 3334, WJC West Building, 1301
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 and Radiation Docket and
Information Center is<PHONE_NUMBER>.

FOR FURTHER INFORMATION CONTACT: Mr. Lewis Weinstock, Air Quality
Assessment Division, Office of Air Quality Planning and Standards, U.S.
Environmental Protection Agency, Mail code C304-06, Research Triangle
Park, NC 27711; telephone:<PHONE_NUMBER>; fax:<PHONE_NUMBER>; email:
<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:

A. Does this action apply to me?

    This action applies to state, territorial, and local air quality
management programs that are responsible for ambient air monitoring
under 40 CFR part 58. Categories and entities potentially regulated by
this action include:

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                 Category                          NAICS \a\ code
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State/territorial/local/tribal government.  924110
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\a\ North American Industry Classification System.

B. What should I consider as I prepare my comments for the EPA?

    1. Submitting CBI. Do not submit this information to the EPA
through http://www.regulations.gov or email. Clearly mark any of the
information that you claim to be CBI. For CBI information in a disk or
CD ROM that you mail to the EPA, mark the outside of the disk or CD ROM
as CBI and then identify electronically within the disk or CD ROM the
specific information that is claimed as CBI. In addition to one
complete version of the comment that includes information claimed as
CBI, a copy of the comment that does not contain the information
claimed as CBI must be submitted for inclusion in the public docket.
Information so marked will not be disclosed except in accordance with
procedures set forth in 40 CFR part 2.
    2. Tips for preparing your comments. When submitting comments,
remember to:
     Follow directions--The agency may ask you to respond to
specific questions or organize comments by referencing a Code of
Federal Regulations (CFR) part or section number.
     Explain why you agree or disagree, suggest alternatives,
and substitute language for your requested changes.
     Describe any assumptions and provide any technical
information and/or data that you used.
     If you estimate potential costs or burdens, explain how
you arrived at your estimate in sufficient detail to allow for it to be
reproduced.
     Provide specific examples to illustrate your concerns and
suggest alternatives.
     Explain your views as clearly as possible, avoiding the
use of profanity or personal threats.

     Make sure to submit your comments by the comment period
deadline identified.

C. Where can I get a copy of this document?

    In addition to being available in the docket, an electronic copy of
this proposed rule will also be available on the Worldwide Web (WWW)
through the Technology Transfer Network (TTN). Following signature, a
copy of this proposed rule will be posted on the TTN's policy and
guidance page for newly proposed or promulgated rules at the following
address: http://www.epa.gov/ttn/oarpg/. The TTN provides information
and technology exchange in various areas of air pollution control. A
redline/strikeout document comparing the proposed revisions to the
appropriate sections of the current rules is located in the docket.

Table of Contents

    The following topics are discussed in this preamble:

I. Background
II. Proposed Changes to the Ambient Monitoring Requirements
    A. General Information
    B. Definitions
    C. Annual Monitoring Network Plan and Periodic Network
Assessment
    D. Network Technical Requirements
    E. Operating Schedules
    F. System Modification
    G. Annual Air Monitoring Data Certification
    H. Data Submittal and Archiving Requirements
    I. Network Design Criteria (Appendix D)
III. Proposed Changes to Quality Assurance Requirements
    A. Quality Assurance Requirements for Monitors Used in
Evaluations for National Ambient Air Quality Standards--Appendix A
    1. General Information
    2. Quality System Requirements
    3. Quality Control Checks for Gases
    4. Quality Control Checks for Particulate Monitors
    5. Calculations for Data Quality Assessment
    B. Quality Assurance Requirements for Monitors Used in
Evaluations of Prevention of Significant Deterioration Projects--
Appendix B
    1. General Information
    2. Quality System Requirements
    3. Quality Control Checks for Gases
    4. Quality Control Checks for Particulate Monitors
    5. Calculations for Data Quality Assessment
IV. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulations and Regulatory 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 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use
    I. National Technology Transfer and Advancement Act
    J. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations

I. Background

    The EPA is proposing revisions to ambient air requirements for
criteria pollutants to provide clarifications to existing requirements
to reduce the compliance burden of monitoring agencies operating
ambient networks. This proposal focuses on ambient monitoring
requirements that are found in 40 CFR part 58 and the associated
appendices (A, D, and new Appendix B), including issues such as
operating schedules, the development of annual monitoring network
plans, data reporting and certification requirements, and the operation
of the required quality assurance (QA) program.
    The EPA last completed a comprehensive revision of ambient air
monitoring regulations in a final rule published on October 17, 2006
(see 71 FR 61236). Minor revisions were completed in a direct final
rule published on June 12, 2007 (see 72 FR 32193). Periodic pollutant-
specific monitoring updates have occurred in conjunction with revisions
to the National Ambient Air Quality Standards (NAAQS). In such cases,
the monitoring revisions were typically finalized as part of the NAAQS
final rules.\1\
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    \1\ Links to the NAAQS final rules are available at: http://www.epa.gov/air/criteria.html.
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II. Proposed Changes to the Ambient Monitoring Requirements

A. General Information

    The following proposed changes to monitoring requirements impact
these subparts of part 58--Ambient Air Quality Surveillance: Subpart
A--General Provisions, and Subpart B--Monitoring Network. Specific
proposed changes to these subparts are described below.

B. Definitions

    The EPA proposes to add and revise several terms to ensure
consistent interpretation within the monitoring regulations and to
harmonize usage of terms with the definition of key metadata fields
that are important components of the Air Quality System (AQS).\2\
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    \2\ The AQS is the EPA's repository of ambient air quality data.
The AQS stores data from over 10,000 monitors, 5,000 of which are
currently active. State, local and tribal agencies collect the data
and submit it to the AQS on a periodic basis. See http://www.epa.gov/ttn/airs/airsaqs/ for additional information.
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    The EPA proposes to add the term ``Certifying Agency'' to the list
of definitions. The certifying agency field was added to AQS in 2013 as
part of the development of a revised process for states and the EPA
Regions to meet the data certification requirements described in 40 CFR
58.15. The new term specifically describes any monitoring agency that
is responsible for meeting data certification requirements for a set of
monitors. In practice, certifying agencies are typically a state,
local, or tribal agency depending on the particular data reporting
arrangements that have been approved by an EPA regional office for a
given state. A list of certifying agencies by individual monitor is
available on the AQS-TTN Web site.\3\
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    \3\ http://www.epa.gov/ttn/airs/airsaqs/memos/
criteriamonitorlistbycertifying
agencyandPQAO.xls.
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    The term ``Chemical Speciation Network'' or CSN is being proposed
for addition to the definition list. The CSN network has been
functionally defined as being comprised of the Speciation Trends
Network sites and the supplemental speciation sites that are
collectively operated by monitoring agencies to obtain PM2.5
chemical species data.
    The term ``Implementation Plan'' is being proposed for addition to
provide more specificity to current definitions that reference the word
``plan'' in their description. The EPA wishes to ensure that references
to State Implementation Plans (SIPs) are not confused with references
to Annual Monitoring Network Plans that are described in 40 CFR 58.10.
    The term ``Local Agency'' is being proposed for revision to clarify
that such organizations are responsible for implementing portions of
annual monitoring network plans. The current definition refers to the
carrying out of a plan which is not specifically defined, leading to
possible confusion with SIPs.
    The term ``meteorological measurements'' is being proposed for
clarification that such measurements refer to required parameters at
NCore and photochemical assessment monitoring stations (PAMS).

    The terms ``Monitoring Agency'' and ``Monitoring Organization'' are
being proposed for clarification to include tribal monitoring agencies
and to simplify the monitoring organization definition to reference the
aforementioned monitoring agency definition.
    The term ``NCore'' is being proposed for revision to remove
nitrogen dioxide (NO2) and lead in PM10 (Pb-
PM10) as a required measurement and to expand the definition
of basic meteorology to specifically reference the required
measurements: Wind speed, wind direction, temperature, and relative
humidity. The EPA clarifies that NO2 was never a required
NCore measurement and that the current definition was erroneous on this
issue. Additionally, the requirement to measure Pb-PM10 at
NCore sites in areas over 500,000 population is being proposed for
elimination in the rule.
    The term ``Near-road NO2 Monitor'' is being proposed for
revision to ``Near-road Monitor.'' This revision is being made to
broaden the definition of near-road monitors to include all such
monitors operating under the specific requirements described in 40 CFR
part 58, appendix D (sections 4.2.1, 4.3.2, 4.7.1(b)(2)) and appendix E
(section 6.4(a), Table E-4) for near-road measurement of
PM2.5 and carbon monoxide (CO) in addition to
NO2.
    The term ``Network Plan'' is being proposed for addition to clarify
that any such references in 40 CFR part 58 refer to the annual
monitoring network plan required in 40 CFR 58.10.
    The term ``Plan'' is being proposed for deletion as its usage has
been replaced with more specific references to either the annual
monitoring network plan required in 40 CFR 58.10 or the SIP approved or
promulgated pursuant to section 110 of the Clean Air Act.
    The term ``Population-oriented Monitoring (or sites)'' is being
proposed for deletion. This term along with the related usage of the
concept of population-oriented monitoring was deleted from 40 CFR part
58 in the 2013 PM2.5 NAAQS final rule (see 78 FR 3235-3236).
As explained in that rule, the action was taken to ensure consistency
with the longstanding definition of ambient air applied to the other
NAAQS pollutants.
    The term ``Primary Monitor'' is being proposed for addition to the
definition list. The usage of this term has become important in AQS to
better define the processes used to calculate design values when more
than one monitor is being operated by a monitoring agency for a given
pollutant. This term identifies the primary monitor used as the default
data source in AQS for creating a combined site record.
    The term ``Primary Quality Assurance Organization'' is being
proposed for revision to include the usage of the acronym, ``PQAO.''
    The terms ``PSD Monitoring Organization'' and ``PSD Monitoring
Network'' are being added to support the proposed new appendix B that
will pertain specifically to QA requirements for prevention of
significant deterioration (PSD) networks.
    The term ``PSD Reviewing Authority'' is being added to support the
addition of appendix B to the part 58 appendices and to clarify the
identification of the lead authority in determining the applicability
of QA requirements for PSD monitoring projects.
    The term ``Reporting Organization'' is being proposed for revision
to clarify that the term refers specifically to the reporting of data
as defined in AQS. The AQS does allow the distinct designation of
agency roles that include analyzing, certifying, collecting, reporting,
and PQAO.
    The term ``SLAMS'' (state and local air monitoring stations) is
being proposed for clarification to clearly indicate that the
designation of a monitor as SLAMS refers to a monitor required under
appendix D of part 58. The SLAMS monitors make up networks that include
NCore, PAMS, CSN, and other state or local agency sites that have been
so designated in annual monitoring network plans.
    The terms ``State Agency'' and ``STN'' are proposed for minor
wording changes for purposes of clarity only.
    The term ``State Speciation Site'' is being proposed for deletion
in lieu of the proposed addition of ``Supplemental Speciation Station''
to better describe the distinct elements of the CSN network which
includes the Speciation Trends Network Stations that are required under
section 4.7.4 of appendix D of part 58 and supplemental speciation
stations which are operated for specific monitoring agency needs and
are not considered to be required monitors under appendix D.

C. Annual Monitoring Network Plan and Periodic Network Assessment

    The EPA finalized the current Annual Monitoring Network Plan
requirement as part of the 2006 amendments to the ambient monitoring
requirements (see 71 FR 61247-61249). The revised requirements were
intended to consolidate separate network plan requirements that existed
for SLAMS and national air monitoring stations (NAMS) networks, clarify
processes for providing public input in the network plans and obtaining
formal EPA Regional Office review, and revise the required plan
elements to address other changes that had occurred in part 58. Since
2006, further revisions to the annual monitoring network plan
requirements have occurred to address new requirements for monitoring
networks including the NCore multi-pollutant network, source-oriented
lead (Pb), near-road monitoring for NO2, CO and
PM2.5, other required NAAQS monitoring, and data quality
requirements for continuous PM2.5 Federal Equivalent Methods
(FEMs).
    The current Annual Monitoring Network Plan requirements state that
plans must be made available for public inspection for at least 30 days
prior to submission to the EPA. Additionally, any plans that propose
SLAMS network modifications are subject to EPA Regional Administrator
approval, and either the monitoring agency or the EPA Regional Office
must provide an opportunity for public comment. This process to improve
transparency pertaining to the planning of ambient monitoring networks
has been successful and the EPA believes that state and local agencies
are increasingly receiving public comments on these plans.\4\ To aid in
the visibility of these plans, the EPA hosts an annual monitoring
network plan summary page on its Ambient Monitoring Technical
Information Center (AMTIC) Web site.\5\
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    \4\ The EPA notes that there is no specified process for
obtaining public input into draft annual monitoring network plans
although the typical process is to post the plans on state or local
Web sites along with an on-line process to obtain public comments.
    \5\ See http://www.epa.gov/ttn/amtic/plans.html.
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    Since the revision of the annual monitoring network plan process in
2006, the EPA has received feedback from its regional offices as well
as some states that the regulatory language pertaining to public
involvement has been unclear. Areas of confusion include determining
the difference between the process of obtaining public inspection
versus comment, the responsibility of monitoring agencies to respond to
public comment in their submitted plans, and the responsibility of the
EPA regional offices to obtain public comment depending on a monitoring
agency's prior action as well as whether the annual monitoring network
plan was modified based on discussions with the monitoring agency
following plan submission.
    The EPA believes that the intent of the 2006 revision to these
requirements was to support wider public involvement in the planning
and implementation of air monitoring

networks, and, to that extent, the solicitation of public comments
prior to the submission of the annual monitoring network plan to the
EPA regional office is a desirable part of the process. Indeed, the EPA
stated in the preamble to the 2006 amendments that ``Although the
public inspection requirement does not specifically require states to
obtain and respond to received comments, such a process is encouraged
with the subsequent transmission of comments to the appropriate EPA
regional office for review'' (see 71 FR 61248).
    Given the heightened interest and visibility of the annual
monitoring network plan process since 2006, the EPA believes that it is
appropriate to propose that the public inspection aspect of this
requirement contained in 40 CFR 58.10(a)(1) be revised to clearly
indicate that obtaining public comment is a required part of the
process, and that plans that are submitted to the EPA regional offices
should address such comments that were received during the public
notice period. The EPA understands that this proposed change in process
could increase burden for those monitoring agencies that have not
routinely incorporated public comments into their annual monitoring
network plan process. However, we believe that these efforts will
increase the transparency of the current process and potentially reduce
questions and adverse comment from stakeholders who have not been
included in annual monitoring network plan discussions prior to
submission to the EPA. For those monitoring agencies that already have
been posting plans for public comment, this proposed change should have
no net effect on workload.
    A related part of the annual monitoring network plan process is
described in 40 CFR 58.10(a)(2) with the distinction that this section
pertains specifically to plans that propose SLAMS modifications and
thereby also require specific approval from the EPA Regional
Administrator. Similar to the public comment issue described above, the
process of obtaining such comment for plans that contain network
modifications was not clearly described, with the regulatory text
initially placing the responsibility on the EPA regional offices to
obtain public comment, but then providing monitoring agencies with the
option of obtaining public comment, which consequently would relieve
the EPA regional office from having to do so. Consistent with the
proposed change to the comment process described above, the EPA is
proposing changes to the text in 40 CFR 58.10(a)(2) to reflect the fact
that public comments will have been required to be obtained by
monitoring agencies prior to submission and that the role of the EPA
regional office will be to review the submitted plan together with
public comments and any modifications to the plan based on these
comments. On an overall basis, the EPA believes that this proposed
change to clearly place the responsibility for obtaining public comment
on monitoring agencies makes sense since these organizations are, in
effect, closer to their stakeholders and in a better position to notify
the public about the availability and key issues contained in annual
monitoring network plans, compared with similar efforts by the EPA
regions that oversee many such agencies.
    On a related note, the EPA emphasizes the value of the partnership
between monitoring agencies and their respective EPA regional offices,
and encourages an active dialogue between these parties during the
development and review of annual monitoring network plans. Although the
monitoring regulations only require that the EPA Regional
Administrators approve annual monitoring network plans that propose
changes to SLAMS stations, the EPA encourages monitoring agencies to
seek formal approval of submitted plans regardless of whether SLAMS
changes are proposed or not. Such a process would ensure that not only
plans with proposed modifications are formally approved, but also that
plans where potential network changes are indeed appropriate but not
proposed, would be subject to discussion. Although the EPA is not
proposing that annual monitoring network plans that do not propose
changes to SLAMS should also be subject to the EPA Regional
Administrator's approval, we support close working relationships
between monitoring agencies and the EPA regions and see value in having
a formal review of all such plans, regardless of whether network
modifications are proposed.
    Another aspect of the annual monitoring network plan requirements
is the listing of required information for each proposed and existing
site as described in 40 CFR 58.10(b). The EPA is proposing to add two
elements to this list as described below.
    First, the EPA is proposing to require that a PAMS network
description be specifically included as a part of the annual monitoring
network plan for any monitoring agencies affected by PAMS requirements.
The requirements for such a plan are already referenced in appendix D,
sections 5.2 and 5.4 of this part. In fact, the requirement for an
``approved PAMS network description provided by the state'' is already
specified in section 5.4. Accordingly, the EPA is proposing that a PAMS
network description be a required element in annual monitoring network
plans for affected monitoring agencies, and that any such plans already
developed for PAMS networks in accordance with section 5 of appendix D
could be used to meet this proposed requirement. The EPA believes that
the burden impact of this proposed change should be minimal, as a
review of archived 2012 annual monitoring network plans posted on the
EPA's AMTIC Web page shows that many such plans already include
references to PAMS stations. For purposes of consistency and clarity,
however, the EPA believes there is merit for proposing this revision to
the annual monitoring network plan requirements so that stakeholders
interested in the operation of PAMS stations can find the relevant
information in one place.
    Second, the EPA is proposing language that affects ``long-term''
Special Purpose Monitors (SPMs), i.e., those SPMs operating for longer
than 24 months whose data could be used to calculate design values for
NAAQS pollutants in cases where the EPA approved methods are being
employed. As long as such monitors are classified as SPMs, their
operation can be discontinued without EPA approval per 40 CFR 58.20(f).
While such operational flexibility is a key component of special
purpose monitoring, the issue can become more complex when longer-term
SPMs measure elevated levels of criteria pollutants and potentially
become design value monitors for a region. In such cases, the EPA is
faced with scenarios where key monitors that can impact the attainment
status of a region can potentially be discontinued without prior
notification or approval. Given the important regulatory implications
of such monitoring network decisions, the EPA believes that it is
important that the ongoing operation and treatment of such SPMs be
specifically called out and discussed in annual monitoring network
plans. Therefore, the EPA is proposing that a new required element be
added to the annual monitoring network plan requirements. Specifically,
the EPA is proposing that such long-term SPMs be identified in the
plans along with a discussion of the rationale for keeping the
monitor(s) as SPMs or potentially reclassifying to SLAMS. The EPA is
not proposing that such monitors must become SLAMS, only that the
ongoing operation of such monitors and the rationale for retaining them
as SPMs be explicitly discussed to avoid confusion

and the potential for unintended complexities in the designations
process if any design value SPMs would be discontinued without adequate
discussion.
    The EPA is proposing minor edits to the annual monitoring network
plan requirements to revise terminology referring to PM2.5
speciation monitoring, to note the proposed addition of appendix B to
the QA requirements (see section III.B of this preamble), and to
clarify that annual monitoring network plans should include statements
addressing whether the operation of each monitor meets the requirements
of the associated appendices in part 58.
    Finally, the issue has arisen concerning the flexibility that the
EPA Regional Administrators have with reference to the approvals that
are required within 120 days of annual monitoring network plan
approval, for example, in the situation where the majority of the
submitted plan is acceptable but one or more of the required elements
is problematic. In these situations, which we believe to be infrequent,
the existing regulatory language provides sufficient flexibility for
such situations to be handled on a case-by-case basis, for example,
through the use of a partial approval process where the Regional
Administrator's approval decision letter specifies what elements of the
submitted plan are approved and what elements are not. Alternatively,
if the plan satisfies the requirements for network adequacy under
appendix D and the monitors are suitable for regulatory decisions
(consistent with the requirements of appendix A), the Regional
Administrator has the discretion to approve the plan, while noting
technical deficiencies to be corrected. We would expect that the
resolution of the specific items under discussion would be documented
through follow-up communications with the submitting monitoring agency
to ensure that a complete record exists for the basis of the annual
monitoring network plan approval.
    The EPA solicits comments on all of the proposed changes to annual
monitoring network plans requirements contained in 40 CFR 58.10.

D. Network Technical Requirements

    The EPA is proposing to revise the language in 40 CFR 58.11(a)(3)
to note the proposed revisions to appendix B to the QA requirements
(see section III.B of this preamble) that would pertain to PSD
monitoring sites.

E. Operating Schedules

    The operating schedule requirements described in 40 CFR 58.12
pertain to the minimum required frequency of sampling for continuous
analyzers (for example, hourly averages) and manual methods for
particulate matter (PM) and Pb sampling (typically 24-hour averages for
manual methods). The EPA is proposing to revise these requirements in
three ways: By proposing added flexibility in the minimum required
sampling for PM2.5 mass sampling and for PM2.5
speciation sampling; by modifying language pertaining to continuous
mass monitoring to reflect revisions in regulatory language that were
finalized in the 2013 p.m. NAAQS final rule; and by clarifying the
applicability of certain criteria that can lead to an increase in the
required sampling frequency, for example, to a daily schedule.
    With regard to the minimum required sampling frequency for manual
PM2.5 samplers, current requirements state that at least a
1-in-3 day frequency is mandated for required SLAMS monitors without a
collocated continuous monitor. For the majority of such manual
PM2.5 samplers, the EPA continues to believe that a 1-in-3
day sampling frequency is appropriate to meet the data quality
objectives that support the PM2.5 NAAQS.\6\ For a subset of
these monitors, however, the EPA believes that some regulatory
flexibility may be appropriate in situations where a particular monitor
is highly unlikely to record a violation of the PM2.5 NAAQS.
Such situations might occur in areas with very low PM2.5
concentrations relative to the NAAQS and/or in urban areas with many
more monitors than are required by appendix D and a subset of those
monitors are reading lower than other monitors in the area. In these
situations, the EPA believes it is appropriate to propose that the
required sampling frequency could be reduced to 1-in-6 day sampling or
another alternate schedule through a case-by-case approval by the EPA
Regional Administrator. Such approvals could be based on factors that
are already described in 40 CFR 58.12(d)(1)(ii) such as historical
PM2.5 data assessments, the attainment status of the area,
the location of design value sites, and the presence of continuous
PM2.5 monitors at nearby locations. The EPA envisions that
the request for such reductions in sampling frequency would occur
during the annual monitoring network plan process as operating
schedules are a required part of the plans as stated in 40 CFR
58.10(b)(4).
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    \6\ According to a retrieval from AQS dated 12-23-2013,
approximately 65% of primary PM2.5 samplers (those
monitors with a parameter occurrence code of ``1'') operated on a 1-
in-3 day sampling frequency.
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    For sites with a collocated continuous monitor, the EPA also
believes that the current regulatory flexibility to reduce to 1-in-6
day sampling or a seasonal sampling schedule is appropriate based on
factors described above, and in certain cases, may also be applicable
to lower reading SLAMS sites without a collocated continuous monitor,
for example, to reduce frequency from 1-in-6 day sampling to a seasonal
schedule. Accordingly, we have proposed such flexibility through
changes in the regulatory language in 40 CFR 58.12(d)(1)(i) and (ii).
    The EPA also believes that some flexibility for sampling frequency
is appropriate to propose for PM2.5 Chemical Speciation
Stations, specifically the Speciation Trends Network (STN) sites that
are at approximately 53 locations.\7\ The STN stations are currently
required to sample on at least a 1-in-3 day frequency with no
opportunity for flexibility. While the EPA firmly believes in the long-
term importance of the STN stations to support the development of SIPs,
modeling exercises, health studies, and the investigation of air
pollution episodes and exceptional events, we do not believe that the
current inflexibility with regard to sampling frequency is in the best
interests of monitoring agencies, the EPA, or stakeholders. For the
past several years, the EPA has been investigating alternative
monitoring technologies such as continuous PM2.5 speciation
methods that can supplement or potentially even replace manual
PM2.5 speciation methods.\8\ As these methods become more
refined, the EPA may wish to selectively reduce sampling frequency at
manual samplers for one or more channels to conserve resources for
reinvestment in other needs within the CSN network. Additionally, the
EPA is currently conducting an assessment of the entire CSN network to
evaluate the long-term viability of the program in the context of
changes in air quality, the recently revised PM NAAQS, rising
analytical costs, and flat or declining resources. Accordingly, for the
reasons mentioned above, the EPA is proposing that a reduction in
sampling frequency from 1-in-3 day be permissible for manual
PM2.5 samplers at STN stations. The approval for such
changes at STN stations, on a case by case basis, would be made by the
EPA Administrator as the authority for changes to STN has

been retained at the Administrator level per appendix D of this part,
section 4.7.4. Factors that would be considered as part of the decision
would include an area's design value, the role of the particular site
in national health studies, the correlation of the site's species data
with nearby sites, and presence of other leveraged measurements. In
practice, we would expect a close working relationship with the EPA
regional offices and monitoring agencies to consider such changes to
STN, preferably as part of the annual monitoring network plan process,
taking into account the findings of the CSN assessment process that is
expected to be completed later in 2014, as well as a parallel effort
being undertaken for the Interagency Monitoring of Protected Visual
Environments (IMPROVE) network.\9\
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    \7\ http://www.epa.gov/ttn/amtic/specgen.html.
    \8\ http://www.epa.gov/ttnamti1/spesunset.html.
    \9\ http://vista.cira.colostate.edu/improve/Default.htm.
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    The EPA is proposing editorial revisions to 40 CFR 58.12(d)(1)(ii)
to harmonize the language regarding the use of continuous FEM or
approved regional methods (ARM) monitors to support sampling frequency
flexibility for manual PM2.5 samplers with the current
language in 40 CFR 58.12(d)(1)(iii) that was revised as part of 2013 PM
NAAQS final rule. Specifically, the phrase ``unless it is identified in
the monitoring agency's annual monitoring network plan as not
appropriate for comparison to the NAAQS and the EPA Regional
Administrator has approved that the data from that monitor may be
excluded from comparison to the NAAQS'' is being proposed for appending
to the current regulatory language. This change reflects the new
process that was finalized in the 2013 PM NAAQS final rule that allows
monitoring agencies to request that continuous PM2.5 FEM
data be excluded from NAAQS comparison based on technical criteria
described in 40 CFR 58.11(e) (see 78 FR 3241-3244). If such requests
are made by monitoring agencies and subsequently approved by the EPA
regional offices as part of the annual monitoring plan process, it
follows that the data from these continuous PM2.5 FEMs would
also not be of sufficient quality to support a request for sampling
reduction for a collocated manual PM2.5 sampler. The EPA
revised the relevant language in one section of 40 CFR 58.12 during the
2013 PM rulemaking but failed to revise a similar phrase in another
section of 40 CFR 58.12. Accordingly, the EPA is proposing the change
to ensure consistent regulatory language throughout 40 CFR 58.12.
Within these editorial changes, we are also proposing the addition of
the phrase ``and the EPA Regional Administrator has approved that the
data from that monitor may be excluded from comparison to the NAAQS''
to the revisions that were made with the 2013 PM NAAQS. This revision
is being proposed to clearly indicate that two distinct actions are
necessary for the data from a continuous PM2.5 FEM to be
considered not comparable to the NAAQS; first, the identification of
the relevant monitor(s) in an agency's annual monitoring network plan,
and, second, the approval by the EPA Regional Administrator of that
request to exclude data. The language used by the EPA in the relevant
sections of 40 CFR 58.12 related to the initial request by monitoring
agencies but did not specifically address the needed approval by the
EPA.
    Finally, the EPA is clarifying the applicability of statements in
40 CFR 58.12(d)(1)(ii) and (iii) that reference the relationship of
sampling frequency to site design values. Specifically, we are
proposing clarifications and revisions affecting the following
statements: (1) ``Required SLAMS stations whose measurements determine
the design value for their area and that are within 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,'' and (2) ``Required SLAMS stations whose measurements
determine the 24-hour design value for their area and whose data are
within 5 percent of the level of the 24-hour
PM2.5 NAAQS must have a Federal Reference Method (FRM) or
FEM operate on a daily schedule if that area's design value for the
annual NAAQS is less than the level of the annual PM2.5
standard.'' Since these provisions were finalized in 2006, there has
been some confusion among monitoring agencies and regional offices
concerning the applicability of the sampling frequency adjustments
since design values are recalculated annually and, in some situations,
such revised design values can either fall below the comparative
criteria or rise above the criteria. For example, if according to 40
CFR 58.12(d)(1)(iii) a sampler must be on a daily sampling schedule
because its design value is within 5 percent of the 24-hour
NAAQS and it meets the other listed criteria, how and when should the
sampling frequency be revised if the referenced 24-hour design value
falls out of the 5 percent criteria the following year? In
an extreme example, what would happen if the 24-hour design value
changed each year to be alternately within the 5 percent criteria and
then not within the criteria?
    It was not the EPA's intention in the 2006 monitoring revisions to
create scenarios in which the required sampling frequencies for
individual samplers would be ``chasing'' annual changes in design
values. Such a framework would be difficult to implement for both
monitoring agencies and regional offices for logistical reasons
including the scheduling of operators and the availability of
PM2.5 filters, and also because of the time lag involved
with reporting and certifying data and the validation of revised design
values, which typically does not occur until the summer following the
completion of each calendar year's sampling. To provide some clarity to
this situation as well as to provide a framework where changes in
sampling frequency occur on a more consistent and predictable basis,
the EPA is proposing that design value-driven sampling frequency
changes be maintained for a minimum 3-year period once such a change is
triggered. Additionally, such changes in sampling frequency would be
required to be implemented no later than January 1 of the year which
followed the recalculation and certification of a triggering design
value. For example, if a triggering design value that required a change
to daily sampling frequency was calculated in the summer of 2014 based
on 2011-2013 certified data, then the affected sampler would be
required to have an increased sampling frequency no later than January
1, 2015, and would maintain that daily frequency through at least 2017,
regardless of changes to the triggering design value in the intervening
years.
    To accomplish these proposed changes, the EPA is proposing changes
in the 40 CFR 58.12 regulatory text to clarify that sampling frequency
changes that are triggered by design values must be maintained until
the triggering design value site no longer meets the criteria for at
least 3 consecutive years. Specifically, these changes include the
insertion of the phrase ``until the design value no longer meets these
criteria for 3 consecutive years'' into 40 CFR 58.12(d)(1)(ii) and the
sentence ``The daily schedule must be maintained until the referenced
design values no longer meet these criteria for 3 consecutive years''
into 40 CFR 58.12(d)(1)(iii). The EPA notes that where a design value
is based on 3 years of data, 3 consecutive years of design values would
require 5 years of data (e.g., 2010-2012, 2011-2013, 2012-2014). New
regulatory

language has been proposed in 40 CFR 58.12(d)(1)(iv) to document the
timing of when design value-driven changes in sampling frequency must
be implemented.
    On balance, the EPA believes that the overall impact of proposed
changes to the operating schedule requirements will be a modest
reduction in the burden for monitoring agencies. We believe that the
number of PM2.5 FRM and CSN samplers impacted by these
proposed changes will be relatively small, but where they occur will
provide some logistical relief for sites that are less critical in
terms of NAAQS implementation and other key objectives. The EPA
solicits comment on all of these proposed changes to 40 CFR 58.12
requirements.

F. System Modification

    In the 2006 monitoring amendments, the EPA finalized a requirement
in 40 CFR 58.14(a) for monitoring agencies to ``develop and implement a
plan and schedule to modify the ambient air quality network that
complies with the finding of the network assessments required every 5
years by 58.10(e).'' The remainder of the associated regulatory
language reads very much like the required procedure for making annual
monitoring network plans available for public inspection, comment, and
the EPA Regional Administrator's approval as described in 40 CFR
58.10(a)(1) and (2). Since 2006, there has been confusion between the
EPA and the monitoring agencies as to whether a separate plan was
required to be submitted by 40 CFR 58.14(a) relative to the annual
monitoring network plan, with that separate plan devoted specifically
to discussing the results of the 5-year network assessment.
    A review of the 2006 monitoring proposal and final rule reveals no
specific discussion concerning the submission of a distinct plan
devoted specifically to the implementation of the 5-year network
assessment. While the EPA continues to support the importance of the
network assessment requirement,\10\ there appears to be no specific
benefit to the requirement for a distinct plan to discuss the 5-year
network assessments, and the inference of the need for such a plan may
be attributable to some redundancy in the aforementioned requirements
when the regulatory language was revised in 2006. Monitoring agencies,
for example, could include a specific section or attachment to the
annual monitoring network plan that fulfilled all the requirements
described in 40 CFR 58.14(a) including how each agency would implement
the findings of the assessment and the schedule for doing so. By
including such information in the annual monitoring network plans, the
implied need to develop a separate plan with the attendant burden of
public posting, obtaining public comment, and the EPA Regional
Administrator's review and approval can be avoided, reducing the burden
on all parties.
---------------------------------------------------------------------------

    \10\ The next 5-year network assessment will be due no later
than July 1, 2015, according to the schedule established by 40 CFR
58.10(d).
---------------------------------------------------------------------------

    In terms of timing, these specific sections or attachments
referring to the 5-year network assessments could be required either in
the year when the assessment is due (e.g., 2015) or in the year
following when the assessment is due (e.g., 2016). The submission in
the year following the network assessment would allow more time for
monitoring agencies to fully consider the results of the 5-year
assessment and would also allow the public more time to review and
comment on the recommendations.
    Accordingly, the EPA is proposing to revise the regulatory language
in 40 CFR 58.14(a) to clearly indicate that a separate plan is not
needed to account for the findings of the 5-year network assessment,
and that the information concerning the implementation of the 5-year
assessment, referred to in the proposed regulatory language as a
``network modification plan,'' shall be submitted as part of the annual
monitoring network plan that is no later than the year after the
network assessment is due.\11\ According to the proposed schedule, the
annual monitoring network plans that are due in 2016, 2021, etc., would
contain the information referencing the network assessments.
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    \11\ Monitoring agencies, at their discretion, could submit the
network modification plan in the year that the assessment is due if
sufficient feedback had been received. On balance, EPA believes that
the extra year following the completion of the network assessment
would be valuable to assure a productive outcome from the assessment
process.
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    The EPA is also proposing to revise an incorrect cross-reference in
the current text of 40 CFR 58.14(a) in which the network assessment
requirement is noted as being contained in 58.10(e) when the correct
cross-reference is 58.10(d).

G. Annual Air Monitoring Data Certification

    The data certification requirement is intended to provide ambient
air quality data users with an indication that all required validation
and reporting steps have been completed, and that the certified data
sets are now considered final and appropriate for all uses including
the calculation of design values and the determination of NAAQS
attainment status. The formal certification process currently involves
the transmission of a data certification letter to the EPA signed by a
senior monitoring agency official that references the list of monitors
being certified. The letter is accompanied by required AQS reports that
summarize the data being certified and the accompanying QA data that
support the validation of the referenced list of monitors. Once the
letter and required reports are submitted to the EPA, the data
certification requirement has been fulfilled. In practice, the EPA has
provided an additional discretionary review of the data certification
submissions by monitoring agencies to make sure the submissions are
complete and that the EPA agrees that the referenced data are of
appropriate quality. When these reviews have been completed, the EPA's
review has been documented by the presence of a specific AQS flag for
each monitor-year of data that has been certified and reviewed.
    The actual breadth of data certification requirements has not
materially changed since the original requirements were finalized in
1979 as part of the requirement for monitoring agencies to submit an
annual SLAMS summary report (see 44 FR 27573). Data certification
requirements were last revised in 2006 when the deadline for
certification was changed to May 1 from July 1 for most measurements.
    Current requirements include the certification of data collected at
all SLAMS and SPMs using FRM, FEM, or ARM methods. In practice, this
requirement includes a very wide range of measurements that are not
limited to criteria pollutants but also extend to non-criteria
pollutant measurements at PAMS stations, meteorological measurements at
PAMS and NCore stations, and PM2.5 chemical speciation
parameters. For monitoring agencies operating these complex stations,
this places an additional burden on the data review and validation
process in addition to the routine procedures already in place to
validate and report data as required by 40 CFR 58.16. For example,
current PAMS requirements include the reporting of approximately 54
individual ``target list'' volatile organic compounds per station while
many dozens of PM2.5 species are reported at CSN stations.
    None of these specialized monitoring programs were in place when
the data certification requirements were originally promulgated and the
large number of measurements being obtained

in typical modern-day monitoring networks has resulted in a burden
overload that has threatened the viability of the data certification
process. For example, monitoring agencies have struggled with the
availability of specific QA checks that can be used to meet the
certification requirements for PAMS and CSN data, and the EPA's
discretionary review of data certification submissions have become
increasingly incomplete or delayed due to the enormous number of
monitors being submitted for certification under the current
requirements.
    The EPA believes that the data certification requirements need to
be revised to streamline the associated workload for monitoring
agencies as well as the EPA so that the process can be focused on those
measurements that have greatest impacts on state programs, namely the
criteria pollutants that support the calculation of annual design
values and the mandatory designations process. By focusing the data
certification process on the NAAQS, the greatest value will be derived
from the certification process and both the monitoring agencies and the
EPA will be able to devote scarce resources to the most critical of
ambient monitoring objectives. The EPA is not implying that the need
for thorough data validation processes is unimportant for non-criteria
pollutants. However we believe that existing QA plans and standard
operating procedures, together with the regulatory language in 40 CFR
58.16(c) to edit and report validated data, is sufficient to assure the
quality of non-criteria pollutant measurements being reported to AQS.
    Accordingly, the EPA is proposing several changes in the data
certification requirements to accomplish a streamlining of this
important process. First, to support the focus on certification of
criteria pollutant measurements, the EPA is proposing to revise
relevant sections of 40 CFR 58.15 to focus the requirement on FRM, FEM,
and ARM monitors at SLAMS and at SPM stations rather than at all SLAMS
which also include PAMS and CSN measurements that may not utilize
federally approved methods. This proposed wording change limits the
data certification requirement to criteria pollutants since the EPA
approved methods do not exist for non-criteria measurements. Second,
the EPA is also proposing that the required AQS reports be submitted to
the Regional Administrator rather than through the Regional
Administrator to the Administrator as is currently required. From a
process standpoint, this proposed change effectively places each EPA
regional office in charge of the entire data certification process
(including the discretionary review) versus the EPA headquarters where
the discretionary reviews have taken place in the past. This delegation
of responsibility for the discretionary review will allow this
important part of the certification process to be shared among the ten
EPA regional offices, and result in a more timely review of
certification results and the posting of appropriate certification
status flags in AQS. The EPA notes that significant progress has
already been made in revising this part of the certification process
and that a new AQS report, the AMP 600, has been developed to more
efficiently support the sharing of relevant information between
certifying agencies and the EPA regional offices.\12\
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    \12\ Note relevant training material available on the AQS TTN
Web site: http://www.epa.gov/ttn/airs/airsaqs/training/
2013Q2WebinarFinal.pdf.
---------------------------------------------------------------------------

    Additionally, minor editorial changes are being proposed in 40 CFR
58.15 to generalize the title of the official responsible for data
certification (senior official versus senior air pollution control
officer) and to remove an outdated reference to the former due date for
the data certification letter (July 1 versus the current due date of
May 1).

H. Data Submittal and Archiving Requirements

    The requirements described in 40 CFR 58.16 address the specific
measurements that must be reported to AQS as well as the relevant
schedule for doing so. Required measurements include criteria
pollutants in support of NAAQS monitoring objectives as well as public
reporting, specific ozone (O3) and PM2.5
precursor measurements such as those obtained at PAMS, NCore, and CSN
stations, selected meteorological measurements at PAMS and NCore
stations, and associated QA data that support the assessment of
precision and bias.
    In 1997, an additional set of required supplemental measurements
was added to 40 CFR 58.16 in support of the newly promulgated FRM for
PM2.5, described in 40 CFR part 50, appendix L. These
measurements included maximum, minimum, and average ambient
temperature; maximum, minimum, and average ambient pressure; flow rate
coefficient of variation (CV); total sample volume; and elapsed sample
time. In the 2006 monitoring amendments, many of these supplemental
measurements were removed from the requirements based on the EPA's
confidence that the PM2.5 FRM was meeting data quality
objectives (see 71 FR 2748). At that time, reporting requirements were
retained for average daily ambient temperature and average daily
ambient pressure, as well as any applicable sampler flags, in addition
to PM2.5 mass and field blank mass. Given the additional
years of data supporting the performance of the PM2.5 FRM as
well as the near ubiquitous availability of meteorological data
available from sources such as the National Weather Service automated
surface observing system \13\ in addition to air quality networks, the
EPA believes that it is no longer necessary to require agencies to
report the average daily temperature and average daily pressure from
manual PM2.5 samplers, thereby providing some modest relief
from the associated reporting burden. Accordingly, the EPA is proposing
to remove AQS reporting requirements for average daily temperature and
average daily pressure as related to PM2.5 measurements with
the expectation that monitoring agencies will retain such measurements
as needed to support data validation needs as well as to fulfill
requirements in associated QA project plans and standard operating
procedures. The EPA is also proposing to remove similar language
referenced elsewhere in 40 CFR 58.16 that pertains to measurements at
Pb sites as well as to other average temperature and average pressure
measurements recorded by samplers or from nearby airports. For the
reasons noted above, the EPA believes that meteorological data are more
than adequately available from a number of sources, and that the
removal of specific requirements for such data to be reported to AQS
represents an opportunity for burden reduction. The EPA notes that the
requirement to report specific meteorological data for NCore and PAMS
stations remains unchanged.
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    \13\ See http://www.nws.noaa.gov/ost/asostech.html.
---------------------------------------------------------------------------

    The EPA is also proposing a change to the data reporting schedule
described in 40 CFR 58.16(b) and (d) to provide additional flexibility
for reporting PM2.5 chemical speciation data measured at CSN
stations. Specifically, we are proposing that such data be required to
be reported to AQS within 6 months following the end of each quarterly
reporting period, as is presently required for certain PAMS
measurements such as volatile organic compounds. This change would
provide an additional 90 days for PM2.5 chemical speciation
data to be reported compared with the current requirement of reporting
90 days after the end of each

quarterly reporting period. This change is being proposed to provide
both the EPA and monitoring agencies with potential data reporting
flexibility as technological and procedural revisions are considered
for the national analytical frameworks that support the CSN network.
Given that the primary objectives of the CSN (and IMPROVE) programs are
to support long-term needs such as SIP development, modeling, and
health studies, the EPA believes that such programs would not be
negatively impacted by the revised reporting requirements and that
potential contractual efficiencies could be realized by allowing more
time for analytical laboratories to complete their QA reviews and
report their results to AQS.

I. Network Design Criteria (Appendix D)

    The EPA is proposing two changes that affect the required suite of
measurements in the NCore network. This multi-pollutant network became
operational on January 1, 2011, and includes approximately 80 stations
that are located in both urban and rural areas.\14\
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    \14\ See http://www.epa.gov/ttn/amtic/ncore/index.html for more
information.
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    The EPA is proposing a minor change to section 3 of appendix D to
part 58, the design criteria for NCore sites. Specifically, we are
proposing to delete the requirement to measure speciated
PM10-2.5 from the list of measurements in section 3(b). An
identical revision was finalized in the text of 40 CFR 58.16(a) in the
2013 p.m. NAAQS final rule (see 78 FR 3244). At that time, we noted the
lack of consensus on appropriate sampling and analytical techniques for
speciated PM10-2.5, and the pending analysis of data from a
pilot project that examined these issues. Based on the supportive
comments received from monitoring agencies and multi-state
organizations, the EPA deleted the requirement for speciated
PM10-2.5 from 40 CFR 58.16(a). During this process, the EPA
inadvertently failed to complete a similar change that was required in
the language of section 3 of appendix D. Accordingly we are proposing
this change to align the NCore monitoring requirements between the two
sections noted above.
    The EPA is also proposing to delete the requirement to measure Pb
at urban NCore sites, either as Pb in Total Suspended Particles (Pb-
TSP) or as Pb-PM10. This requirement was finalized as part
of the reconsideration of Pb monitoring requirements that occurred in
2010 (see 75 FR 81126). At that time, we noted that monitoring of Pb at
such nonsource locations at NCore sites would support the
characterization of typical neighborhood-scale Pb concentrations in
urban areas to assist with the understanding of the risk posed by Pb to
the general population. We also noted that such information could
assist with the determination of nonattainment boundaries and support
the development of long-term trends.
    Since this requirement was finalized in late 2010, nonsource lead
data has been measured at 50 urban NCore sites, with the majority of
sites having already collected at least 2 years of data. In all cases,
valid ambient Pb readings have been low, with maximum 3-month rolling
averages typically reading around 0.01 micrograms per cubic meter as
compared to the NAAQS level of 0.15 micrograms per cubic meter.\15\ We
expect the majority of sites to have the 3 years necessary to calculate
a design value following the completion of monitoring in 2014. Given
the uniformly low readings being measured at these NCore sites, we
believe it is appropriate to consider eliminating this requirement. As
noted in the associated docket memo, nonsource Pb data will continue to
be measured (as Pb-PM10) at the 27 National Air Toxics
Trends Sites (NATTS) and at hundreds of PM2.5 speciation
stations that comprise the CSN and IMPROVE networks. The EPA believes
that these ongoing networks adequately support the nonsource monitoring
objectives articulated in the 2010 Pb monitoring reconsideration.
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    \15\ See supporting information for reconsideration of existing
requirements to monitor for lead at urban NCore site, Kevin
Cavender, Docket number EPA-HQ-OAR-2013-0619.
---------------------------------------------------------------------------

    Accordingly, the EPA is proposing to delete the requirement to
monitor for nonsource Pb at NCore sites from appendix D of 40 CFR part
58.\16\ Given the requirement to collect a minimum of 3 years of Pb
data in order to support the calculation of design values, the EPA
proposes that monitoring agencies would be able to request permission
to discontinue nonsource monitoring following the collection of at
least 3 years of data at each urban NCore site.\17\ Affected monitoring
agencies should work closely with their respective EPA regional offices
to ensure coordination of these changes to the network.
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    \16\ Specific revisions are proposed in 40 CFR part 58, appendix
D, section 3(b) and sections 4.5(b) and 4.5(c).
    \17\ The EPA will review requests for shutdown under the
provisions of 40 CFR 58.14. Although EPA anticipates that these
nonsource monitors will have design values well below the NAAQS and
will be eligible to be discontinued after three years of data have
been collected, in the event that a monitor records levels
approaching the NAAQS it may not qualify to be discontinued.
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    The EPA solicits comments on these proposed changes to Pb
monitoring requirements.

III. Proposed Changes to Quality Assurance Requirements

A. Quality Assurance Requirements for Monitors Used in Evaluations for
National Ambient Air Quality Standards--Appendix A

1. General Information
    The following proposed changes to monitoring requirements impact
these subparts of part 58--Ambient Air Quality Surveillance; appendix
A--Quality Assurance Requirements for SLAMS, SPMs and PSD Air
Monitoring. Changes that affect the overall appendix follow while those
specific to the various sections of the appendix will be addressed
under a specific section heading. The EPA notes that the entire
regulatory text section for appendix A is being reprinted with this
proposal since this section is being reorganized for clarity as well as
being selectively revised as described in detail below. Likewise,
although the EPA is proposing a new appendix B to apply to PSD
monitors, much of the content of appendix B is taken directly from the
existing requirements for these monitors set forth in appendix A. The
EPA is soliciting comment on the specific provisions of appendices A
and B that are being proposed for revision. However, there are a number
of provisions that are being reprinted in the regulatory text solely
for clarity to assist the public in understanding the changes being
proposed; the EPA is not soliciting comment on those provisions and
considers changes to those provisions to be beyond the scope of this
rulemaking.
    The QA requirements in appendix A have been developed for measuring
the criteria pollutants of O3, NO2, sulfur
dioxide (SO2), CO, Pb and PM (PM10 and
PM2.5) and are minimum requirements for monitoring these
ambient air pollutants for use in NAAQS attainment demonstrations. To
emphasize the objective of this appendix, the EPA proposes to change
the title of appendix A to ``Quality Assurance Requirements for
Monitors used in Evaluations of National Ambient Air Quality
Standards,'' and remove the terms SLAMS and SPMs from the title. We do,
however, in the applicability paragraph, indicate that any monitor
identified as SLAMS must meet the appendix A criteria in order to avoid
any confusion about SLAMS monitors measuring criteria pollutants.

Special purpose monitors may in fact be monitoring for a criteria
pollutant for other objectives than NAAQS determinations. Therefore,
appendix A attempts to clarify in the title and the applicability
section that the QA requirements specified in this appendix are for
criteria pollutant monitors that are designated, through the part 58
ambient air regulations and monitoring organization annual monitoring
network plans, as eligible to be used for NAAQS evaluation purposes.
The applicability section also provides a reporting mechanism in AQS to
identify any criteria pollutant monitors that are not used for NAAQS
evaluations. The criteria pollutants identified for NAAQS exclusion
will require review and approval by the EPA regional offices and will
increase transparency and efficiencies in the NAAQS designation, data
quality evaluation and data certification processes.
    The current appendix A regulation has separate sections for
automated (continuous) and manual method types. Since there are
continuous and manual methods for measuring PM which have different
quality control (QC) requirements, monitoring organizations have found
it difficult to navigate the current appendix A requirements. The EPA
proposes to reformat the document by pollutant rather than by method
type. The four gaseous pollutants (CO, NO2, SO2
and O3) will be contained in one section since the QC
requirements are very similar, and separate sections will be provided
for PM10, PM2.5, and Pb.
    In the 2006 monitoring rule revisions, the PSD QA requirements,
which were previously in appendix B, were added to appendix A and
appendix B was reserved. The PSD requirements, in most cases, mimicked
appendix A in structure but because PSD monitoring is often only for a
period of one year, some of the frequencies of implementation of the
PSD requirements are higher than the appendix A requirements. In
addition, the agencies governing the implementation, assessment and
approval of the QA requirements are different for PSD and ambient air
monitoring for NAAQS decisions (i.e., the EPA regions for appendix A
versus reviewing authorities for PSD). The combined regulations have
caused confusion among monitoring organizations and those implementing
PSD requirements, and the EPA proposes that the PSD requirements be
moved back to a separate appendix B. This change would also provide
more flexibility for revision if changes in either appendix are needed.
Details of this proposed change will follow in Section III.B.
    Finally, the EPA proposes that the appendix A regulation emphasize
the use of PQAO and moved the definition and explanation to the
beginning of the regulation in order to ensure that the application and
use of PQAO in appendix A is clearly understood. The definition for
PQAO is not being proposed for change. Since the PQAO can be a
consolidation of a number of local monitoring organizations, the EPA
proposes to add a sentence clarifying that the agency identified as the
PQAO (usually the state agency) will be responsible for overseeing that
the appendix A requirements are being met by all consolidated local
agencies within the PQAO. Current appendix A regulation requires PQAOs
to be approved by the EPA regions during network reviews or audits. The
EPA believes this approval can occur at any time and proposes to
eliminate the wording that suggests that PQAO approvals can only occur
during events like network reviews or audits.
2. Quality System Requirements
    The EPA proposes to remove the QA requirements for
PM10-2.5 (see current sections 3.2.6, 3.2.8, 3.3.6, 3.3.8,
4.3). Appendix A has traditionally been used to describe the QA
requirements of the criteria pollutants used in making NAAQS attainment
decisions. While the 40 CFR part 58 Ambient Air Monitoring regulation
requires monitoring for the CSN, PAMS, and total oxides of Nitrogen
(NOy) for NCore, the QA requirements for these networks are
found in technical assistance documents and not in appendix A. In 2006,
the EPA proposed a PM10-2.5 NAAQS along with requisite QA
requirements in appendix A. While the PM10-2.5 NAAQS was not
promulgated, PM10-2.5 monitoring was required to be
performed at NCore sites and the EPA proposed requisite QA requirements
in appendix A. Some of the PM QC requirements, like collocation for
precision and the performance evaluation programs for bias, are
accomplished on a percentage of monitoring sites within a PQAO. For
example, collocated sampling for PM2.5 and PM10
is required at approximately 15 percent of the monitoring sites within
a PQAO. Since virtually every NCore site is the responsibility of a
different PQAO, the appendix A requirements for PM10-2.5, if
implemented at the PQAO level, would have been required to be
implemented at almost every NCore site, which would have been expensive
and an unintended burden. Therefore, the EPA required the
implementation of the PM10-2.5 QC requirements at a national
level and worked with the EPA regions and monitoring organizations to
identify the sites that would implement the requirements. The
implementation of the PM10-2.5 QC requirements at NCore
sites fundamentally changed how QC is implemented in appendix A and has
been a cause of confusion with these parties. Since PM10-2.5
is not a NAAQS pollutant and the QC requirements cannot be cost-
effectively implemented at a PQAO level, the EPA is proposing to
eliminate the PM10-2.5 requirements including flow rate
verifications, semi-annual flow rate audits, collocated sampling
procedures, and the PM10-2.5 Performance Evaluation Program
(PEP). Similar to the technical assistance documents associated for the
CSN \18\ and PAMS \19\ networks, the EPA will develop QA guidance for
the PM10-2.5 network which will afford more flexibility for
implementation and revision of QC activities for PM10-2.5.
---------------------------------------------------------------------------

    \18\ See http://www.epa.gov/ttn/amtic/specguid.html for CSN
quality assurance project plan.
    \19\ See http://www.epa.gov/ttn/amtic/pamsguidance.html for PAMS
technical assistance document.
---------------------------------------------------------------------------

    The EPA proposes that the QA Pb requirements of collocated sampling
(see current section <IP_ADDRESS>) and Pb performance evaluation procedures
(see current section <IP_ADDRESS>) for non-source NCore sites be eliminated.
The 2010 Pb rule in 40 CFR part 58, appendix D, section 4.5(b), added a
requirement to conduct non-source oriented Pb monitoring at each NCore
site in a core based statistical area (CBSA) with a population of
500,000 or more. This requirement had some monitoring organizations
implementing Pb monitoring at only one site, the NCore site. Since the
appendix A requirements are focused on PQAOs, the QC requirements would
increase at PQAOs who were required to implement Pb monitoring at
NCore. Similar to the PM10-2.5 QA requirements,
the requirement for Pb at NCore sites forced the EPA away from a focus
on PQAOs to working with the EPA regions and monitoring organizations
for implementation of the Pb Performance Evaluation Program (Pb-PEP) at
national levels. Therefore, the EPA is proposing to eliminate the
collocation requirement and the Pb-PEP requirements while retaining the
requirements for flow rate verifications and flow rate audits which do
not require additional monitors or independent sampling and analysis.
Similar to the CSN and PAMS programs, the EPA will develop QA guidance
for the Pb NCore network which will afford more flexibility for change/
revision to accommodate Pb monitoring at non-source NCore sites.
Additionally, the

EPA is proposing to delete the requirement to measure Pb at these
specific NCore sites, either as Pb-TSP or as Pb-PM10 (see
section II.I of this rule). If that proposed change is finalized, it
will eliminate the need for any associated QA requirements including
collocation, Pb-PEP or any QC requirements for these monitors. If the
proposed change to NCore Pb requirements is not finalized, then the EPA
will consider the proposed revision to QA requirements as described
above on its own merits.
    The EPA proposes that quality management plan (QMP) (current
section 2.1.1) and quality assurance project plan (QAPP) (current
section 2.1.2) submission and approval dates be reported by monitoring
organizations and the EPA. This will allow for timely and accurate
reporting of this information. Since 2007, the EPA has been tracking
the submission and approval of QMPs and QAPPs by polling the EPA
regions each year and updating a spreadsheet to the AMTIC Web site. The
development of the annual spreadsheet is time consuming on the part of
monitoring organizations and the EPA. It is expected that simplified
reporting at the monitoring organization and the EPA regional office
level to AQS will reduce entry errors and the burden of incorporating
this information into annual spreadsheets, and increase transparency of
this important quality system documentation. In order to reduce the
initial burden of this data entry activity, the EPA has populated AQS
with the last set of updated QMP and QAPP data from the annual
spreadsheet review cycle. If this portion of the proposal is finalized,
monitoring organizations will only need to update AQS as necessary.
    In addition, some monitoring organizations have received delegation
of authority to approve their QAPP through the monitoring
organization's own QA organization. The EPA proposes that if a PQAO or
monitoring organization has been delegated authority to review and
approve their QAPP, an electronic copy must be submitted to the EPA
regional office at the time it is submitted to the PQAO/monitoring
organization's QAPP approving authority. Submission of an electronic
version to the EPA at the time of completion is not considered an added
burden on the monitoring organization because such submission is
already a standard practice as part of the review process for technical
systems audits.
    The EPA proposes to add some clarifying language to the section
describing the National Performance Evaluation Program (NPEP) (current
section 2.4) explaining self-implementation of the performance
evaluation by the monitoring organization. The clarification also adds
the definition of independent assessment which is included in the PEP
(PM2.5-PEP, Pb-PEP and National Performance Audit Program
(NPAP)) QAPPs and guidance and is included in the self-implementation
memo sent to the monitoring organizations on an annual basis and posted
on the AMTIC Web site \20\. The clarification is not a new requirement
but provides a better reference for this information in addition to the
annual memo sent to the monitoring organizations.
---------------------------------------------------------------------------

    \20\ See http://www.epa.gov/ttn/amtic/npepqa.html.
---------------------------------------------------------------------------

    The EPA proposes to add some clarifying language to the technical
systems audits (TSA) section (current section 2.4). The current TSA
requirements are performed at the monitoring organization level. Since
the EPA is revising the language in appendix A to focus on PQAOs
instead of monitoring organizations, this may have an effect on those
EPA Regions that want to perform TSA on monitoring organizations within
a PQAO (a PQAO can be a single monitoring organization or a
consolidation of a number of local monitoring organizations). The EPA
proposes a TSA frequency of 3 years for each PQAO, but includes
language that if a PQAO is made up of a number of monitoring
organizations, all monitoring organizations within the PQAO be audited
within 6 years. This proposed language maintains the every 3 years TSA
requirement as it applies to PQAOs but provides additional flexibility
for the EPA regions to audit every monitoring organization within the
PQAO every 6 years. This change does not materially affect the burden
on monitoring organizations.
    The EPA proposes to require monitoring organizations to complete an
annual survey for the Ambient Air Protocol Gas Verification Program
(AA-PGVP) (current section 2.6.1). Since 2009, the EPA has had a
separate information collection request (ICR) requiring monitoring
organizations to complete an annual survey of the producers that supply
their gas standards (for calibrations and QC) in order to be able to
select standards from these producers for verification. The survey
generally takes less than 10 minutes to complete. The EPA proposes to
add the requirement to appendix A. In addition, the EPA proposes to add
language that monitoring organizations participate, at the request of
the EPA, in the AA-PGVP by sending a gas standard to one of the
verification laboratories every 5 years. Since many monitoring
organizations already volunteer to send in cylinders, this proposed new
requirement may not materially affect most agencies and will not affect
those agencies not using gas standards.
3. Quality Control Checks for Gases
    The EPA proposes to lower the audit concentrations (current section
3.2.1) of the one-point QC checks to 0.005 and 0.08 parts per million
(ppm) for SO2, NO2, and O3 (currently
0.01 to 0.1 ppm), and to between 0.5 and 5 ppm for CO monitors
(currently 1 and 10 ppm). With the development of more sensitive
monitoring instruments with lower detection limits, technical
improvements in calibrators, and lower ambient air concentrations in
general, the EPA feels this revision will better reflect the precision
and bias of the data. Since the audit concentrations are selected using
the mean or median concentration of typical ambient air concentrations
(guidance on this is provided in the QA Handbook \21\), the EPA is
proposing to add some clarification to the current language by
requiring monitoring organizations to select either the highest or
lowest concentration in the ranges identified if their mean or median
concentrations are above or below the prescribed range. There is no
additional burden to this requirement since the frequency is the same
and the audit concentrations are not so low as to make them
unachievable to generate or measure.
---------------------------------------------------------------------------

    \21\ QA Handbook for Air Pollution Measurement Vol. II, Ambient
Air Quality Monitoring Program at: http://www.epa.gov/ttn/amtic/qalist.html.
---------------------------------------------------------------------------

    The EPA proposes to remove reference to zero and span adjustments
(current section <IP_ADDRESS>) and revise the one-point QC language to
simply require that the QC check be conducted before any calibration or
adjustment to the monitor. Recent revisions of the QA Handbook
discourage the implementation of frequent span adjustments so the
proposed language helps to clarify that no adjustment be made prior to
implementation of the one-point QC check.
    The EPA proposes to remove the requirement (current section 3.2.2)
to implement an annual performance evaluation for one monitor in each
calendar quarter when monitoring organizations have less than four
monitoring instruments. The minimum requirement for the annual
performance evaluation for the primary monitor at a site is one per
year. The current regulation requires evaluation of the

monitors at 25 percent per quarter so that the performance evaluations
are performed in all four quarters. There are cases where some
monitoring organizations have less than four primary monitors for a
gaseous pollutant, and the current language suggests that a monitor
already receiving a performance evaluation be re-audited to provide for
performance evaluations in all four quarters. This is a burden
reduction for monitoring agencies operating smaller networks and does
not change the requirement of an annual performance evaluation for each
primary monitor.
    The current annual performance evaluation language (current section
<IP_ADDRESS>) requires that the audits be conducted by selecting three
consecutive audit levels (currently five audit levels are provided in
appendix A). Due to the implementation of the NCore network, the
inception of trace gas monitors, and lower ambient air concentrations
being measured under typical circumstances, there is a need for audit
levels at lower concentrations to more accurately represent the
uncertainties present in much of the ambient data. The EPA proposes to
expand the audit levels from five to ten and remove the requirement to
audit three consecutive levels. The current regulation also requires
that the three audit levels should bracket 80 percent of the ambient
air concentrations measured by the analyzer. This current language has
caused some confusion and monitoring organizations have requested the
use of an audit point to establish monitor accuracy around the NAAQS
levels. Therefore, the EPA is proposing to revise the language so that
two of the audits levels selected represent 10-80 percent of routinely-
collected ambient concentrations either measured by the monitor or in
the PQAOs network of monitors. The proposed revision allows the third
point to be selected at the NAAQS level (e.g., 75 ppb for
SO2) or above the highest 3-year routine hourly
concentration, whichever is greater.
    The EPA proposes to revise the language (current section
<IP_ADDRESS>(a)) addressing the limits on excess nitric oxide (NO) that must
be followed during gas phase titration (GPT) procedures involving
NO2 audits. The current NO limit (maintaining at least 0.08
ppm) is very restrictive and requires auditors to make numerous mid-
audit adjustments during a GPT that result in making the NO2
audit a very time consuming procedure. Monitoring agency staff have
advised us that the observance of such excess NO limits has no apparent
effect on NO2 calibrations being conducted with modern-day
GPT capable calibration equipment and, therefore, that the requirement
in the context of performing audits is unnecessary.\22\ We also note
the increasing availability of the EPA approved direct NO2
methods that do not utilize converters, rendering the use of GPT
techniques that require the output of NO and NOX to be a
potentially diminishingly used procedure in the future. Accordingly, we
have proposed a more general statement regarding GPT that acknowledges
the ongoing usage of monitoring agency procedures and guidance
documents that have successfully supported NO2 calibration
activities. The EPA believes that if such procedures have been
successfully used during calibrations when instrument adjustments are
potentially being made, then such procedures are appropriate for audit
use when instruments are not subject to adjustment. The EPA solicits
comment on this proposed generalization of the GPT requirements,
including whether a more specific set of requirements similar to the
current excess NO levels can be developed based on operational
experience and/or peer reviewed literature.
---------------------------------------------------------------------------

    \22\ See supporting information in Excess NO Issue paper, Mike
Papp and Lewis Weinstock, Docket number EPA-HQ-OAR-2013-0619.
---------------------------------------------------------------------------

    The EPA proposes to remove language (current section <IP_ADDRESS>(b)) in
the annual performance evaluation section that requires regional
approval for audit gases for any monitors operating at ranges higher
that 1.0 ppm for O3, SO2 and NO2 and
greater than 50 ppm for CO. The EPA does not need to approve a
monitoring organization's use of audit gases to audit above proposed
concentration levels. There should be very few cases where a
performance evaluation needs to be performed above level 10, but there
may be some legitimate instances (e.g., SO2 audits in areas
impacted by volcanic emissions). Since data reported to AQS above the
highest level may be flagged or rejected, the EPA proposes that PQAOs
notify the EPA regions of sites auditing at concentrations above level
10 so that reporting accommodations can be made.
    The EPA proposes to provide additional explanatory language in
appendix A to describe the NPAP (current section 2.4). The NPAP has
been a long standing program for the ambient air monitoring community.
The NPAP is a performance evaluation which is a type of audit where
quantitative data are collected independently in order to evaluate the
proficiency of an analyst, monitoring instrument or laboratory. It has
been briefly mentioned in section 2.4 of the current appendix A
requirements. Since 2007, the EPA has distributed a memo to all
monitoring organizations in order to determine whether the monitoring
organization plans to self-implement the NPAP program or utilize the
federally implemented program. In order to make this decision, the NPAP
adequacy and independence requirements are described in the memo. The
EPA proposes to include these same requirements in appendix A in a
separate section for NPAP. In addition, the memo currently states that
20 percent of the sites would be audited each year and, therefore, all
sites would be audited in a 5-year period. Since there is a possibility
that monitoring organizations may want some higher priority sites
audited more frequently, the EPA is proposing to revise the language to
require all sites to be audited within a 6-year period to provide more
flexibility and discretion for monitoring agencies. This revision does
not change the number of sites audited in any given year, but allows
for increased frequency of sites deemed as high priority.
4. Quality Control Checks for Particulate Monitors
    The EPA proposes to require that flow rate verifications (current
section 3.2.3) be reported to AQS. Particulate matter concentrations
(e.g., PM2.5, PM10, Pb) are reported in mass per
unit of volume (e.g., [mu]g/m\3\). Flow rate verifications are
implemented at required frequencies in order to ensure that the PM
sampler is providing an accurate and repeatable measure of volume which
is critical for the determination of concentration. If a given flow
rate verification does not meet acceptance criteria, the EPA guidance
suggests that data may be invalidated back to the most recent
acceptable verification which is why these checks are performed at
higher frequencies. Implementation of the flow rate verification is
currently a requirement, but the reporting to AQS has only been a
requirement for PM10 continuous instruments. This is the
only QC requirement in appendix A that was not fully required for
reporting for all pollutants and has been a cause of confusion. When
performing TSAs, the EPA regions review the flow rate verification
information. There are cases where it is difficult to find the flow
rate verification information to ascertain completeness, data quality
and whether corrective actions have been implemented in the case of
flow rate verification failures. In addition, the EPA regions have
mentioned that some of the monitoring organizations have

been reporting this data to AQS in an effort to increase transparency
and reliability in data quality. In a recent review of 2012 data, out
of the 1,110 SLAMS PM2.5 samplers providing flow rate audit
data (which are required to be reported), flow rate verification data
was also reported for 543 samplers or about 49 percent for the samplers
with flow rate audit data. With the development of a new QA transaction
in AQS, we believe that the reporting of flow rate verification data
would improve the evaluation of data quality for data certification and
at national levels, provide consistent interpretation in the regulation
for all PM pollutants without being overly burdensome (approximately 12
per sampler per year).
    In addition, the flow rate verification requirements for all the
particulate monitors suggest randomization of the implementation of
flow rate verifications with respect to time of day, day of the week
and routine service and adjustments. Since this is a suggestion, the
EPA proposes to remove this language from the regulation and instead
include it in QA guidance.
    The EPA proposes to add clarifying language to the PM2.5
collocation requirements (current section 3.2.5) that a site can only
count for the collocation of the method designation of the primary
monitor at that site. Precision is estimated at the PQAO level and at
15 percent of the sites for each method designation that is designated
as a primary monitor. When developing the collocation requirements, the
EPA intended to have the collocated monitors distributed to as many
sites as possible in order to capture as much of the temporal and
spatial variability in the PQAO. Therefore, since there can be only one
primary monitor at a site for any given time period, it was originally
intended that the primary monitor and the QA collocated monitor (for
the primary) at a monitoring site count as one collocation. There have
been some cases where multiple monitoring methods have been placed at a
single site to fulfill multiple collocation requirements, which is not
the intent of the current requirement. For example, a site (Site A) may
have a primary monitor that is designated as a FRM (FRM A). This site
may also have a FEM (FEM B) at the site that is not the primary
monitor. If this site was selected for collocation, then the QA
collocated monitor must be the same method designation as the primary,
so the site would be collocated with another FRM A monitor. For primary
monitors that are FEMs, the current requirement calls for the first QA
collocated monitor of a FEM primary monitor be a FRM monitor. Some
monitoring organizations have been using the collocated FRM monitors at
Site A to satisfy the collocation requirements for other sites (e.g.,
Sites B, C, D) that have a FEM (FEM B or other FEM) as the primary
monitor rather than placing a QA collocated FRM monitor at Site B (C or
D). This was not the intent of the original regulation and the EPA
provided additional guidance to monitoring organizations in 2010 \23\
on the correct (intended) interpretation. This revision does not change
the current regulation and does not increase or decrease burden, but is
intended to provide clarity on how the PQAO identifies the number and
types of monitors needed to achieve the collocation requirements.
---------------------------------------------------------------------------

    \23\ QA EYE Issue 9 Page 3 at: http://www.epa.gov/ttn/amtic/qanews.html.
---------------------------------------------------------------------------

    The EPA proposes to provide more flexibility to monitoring
organizations when selecting sites for collocation. Appendix A
currently (current section <IP_ADDRESS>) requires 80 percent of the
collocated monitors be deployed at sites within 20 percent
of the NAAQS and if the monitoring organization does not have sites
within that range, then 60 percent of the sites are to be deployed
among the highest 25 percent of all sites within the network.
Monitoring organizations have found this difficult to achieve. Some
monitoring organizations do not have many sites and, at times, due to
permission, access and limited space issues, the requirement was not
always achievable. Realizing that the collocated monitors provide
precision estimates for the PQAO (since only 15 percent of the sites
are collocated), while also acknowledging that sites that measure
concentrations close to the NAAQS are important, the EPA proposes to
require that 50 percent (reduction from 80 percent) of the collocated
monitors be deployed at sites within 20 percent of the
NAAQS, and if the monitoring organization does not have sites within
that range, then 50 percent of the sites are to be deployed among the
highest sites within the network. Although this requirement does not
change the number of sites requiring collocation, it does provide the
monitoring organizations additional flexibility in its choice of
collocated sites.
5. Calculations for Data Quality Assessment
    In order to provide reasonable estimates of data quality, the EPA
uses data above an established threshold concentration usually related
to the detection limits of the measurement. Measurement pairs are
selected for use in the precision and bias calculations only when both
measurements are above a threshold concentration.
    For many years, the threshold concentration for Pb precision and
bias data was 0.02 ug/m\3\. The EPA promulgated a new Pb FRM (see 78 FR
40000) utilizing the Inductively Coupled Plasma Mass Spectrometry (ICP-
MS) analysis technique in 2013 as a revision to appendix G of 40 CFR
part 50 \24\. This new FRM demonstrated method detection limits (MDLs)
\25\ below 0.0002 [mu]g/m\3\, which is well below the EPA requirement
of five percent of the current Pb NAAQS level of 0.15 [mu]g/m\3\ or
0.0075 [mu]g/m\3\. As a result of the increased sensitivity inherent in
this new FRM, the EPA proposes to lower the acceptable Pb concentration
(current section 4) from the current value of 0.02 ug/m\3\ to 0.002
[mu]g/m\3\ for measurements obtained using the new Pb FRM and other
more recently approved equivalent methods that have the requisite
increased sensitivity.\26\ The current 0.02 ug/m\3\ value will be
retained for the previous Pb FRM that has subsequently been re-
designated as Federal Equivalent Method EQLA-0813-803, as well as older
equivalent methods that were approved prior to the more recent work on
developing more sensitive methods. Since ambient Pb concentrations are
lower and methods more sensitive, lowering the threshold concentration
will allow much more collocated information to be evaluated which will
provide more representative estimates of precision and bias.
---------------------------------------------------------------------------

    \24\ See 78 FR 40000, July 3, 2013.
    \25\ MDL is described as the minimum concentration of a
substance that can be measured and reported with 99-percent
confidence that the analyte concentration is greater than zero.
    \26\ FEMS approved on or after March 4, 2010, have the required
sensitivity to utilize the 0.002 [mu]g/m\3\ reporting limit with the
exception of manual equivalent method EQLA-0813-803, the previous
FRM based on flame atomic absorption spectroscopy.
---------------------------------------------------------------------------

    The EPA also proposes to remove the total suspended particulate
(TSP) threshold concentration for precision and bias since TSP is no
longer a NAAQS required pollutant and the EPA no longer has QC
requirements for it.
    The EPA proposes to remove the statistical check currently
described in section 4.1.5 of appendix A. The check was developed to
perform a comparison of the one-point QC checks and the annual
performance evaluation data performed by the same PQAO. The section
suggests that 95 percent of all the bias estimates from the annual
performance evaluation (reported as a

percent difference) should fall within the 95 percent probability
interval developed using the one-point QC checks. The problem with this
check is that PQAOs with very good repeatability on the one-point QC
check data had a hard time meeting this requirement since the
probability interval became very tight, making it more difficult for
better performing PQAOs to meet the requirement. Separate statistics to
evaluate the one-point QC checks and the performance evaluations are
already promulgated, so the removal of this check does not affect data
quality assessments.
    Similar to the statistical comparison of performance evaluations
data, the EPA proposes to remove the statistical check (current section
4.2.4) to compare the flow rate audit data and flow rate verification
data. The existing language suggests that 95 percent of all the flow
rate audit data results (reported as percent difference) should fall
within the 95 percent probability interval developed from the flow rate
verification data for the PQAO. The problem, as with the one-point QC
check, was that monitoring organizations with very good repeatability
on the flow rate verifications had a hard time meeting this requirement
since the probability interval became very tight, making it difficult
for better performing PQAOs to meet the requirement. Separate
statistics to evaluate the flow rate verifications and flow rate audits
are already promulgated, so the removal of this check does not affect
data quality assessments.

B. Quality Assurance Requirements for Monitors Used in Evaluations of
Prevention of Significant Deterioration Projects-Appendix B

1. General Information
    The following proposed changes to monitoring requirements impact
these subparts of part 58--Ambient Air Quality Surveillance; appendix
B--Quality Assurance Requirements for Prevention of Significant
Deterioration (PSD) Air Monitoring. Changes that affect the overall
appendix follow while those specific to the various sections of the
appendix will be addressed under specific section headings. Since the
PSD QA have been included in appendix A since 2006, section headings
refer to the current appendix A sections.
    The quality assurance requirements in appendix B have been
developed for measuring the criteria pollutants of O3,
NO2, SO2, CO, PM2.5, PM10
and Pb and are minimum QA requirements for the control and assessment
of the quality of the PSD ambient air monitoring data submitted to the
PSD reviewing authority \27\ or the EPA by an organization operating a
network of PSD stations.
---------------------------------------------------------------------------

    \27\ Permitting authority and reviewing authority are often used
synonymously in PSD permitting. Since reviewing authority has been
defined in 40 CFR 51.166(b), it is used throughout appendix B.
---------------------------------------------------------------------------

    In the 2006 monitoring rule revisions, the PSD QA requirements,
which were previously in appendix B, were consolidated with appendix A
and appendix B was held in reserve. The PSD requirements, in most
cases, parallel appendix A in structure and content but because PSD
monitoring is only required for a period of one year or less, some of
the frequencies of implementation of the QC requirements for PSD are
higher than the corresponding appendix A requirements. In addition, the
agencies governing the implementation, assessment and approval of the
QA requirements are different; the reviewing authorities for PSD
monitoring and the EPA regions for ambient air monitoring for NAAQS
decisions. The combined regulations have caused confusion or
misinterpretations of the regulations among the public and monitoring
organizations implementing NAAQS or PSD requirements, and have resulted
in failure, in some cases, to perform the necessary QC requirements.
Accordingly, the EPA proposes that the PSD QA requirements be removed
from appendix A and returned to appendix B which is currently reserved.
Separating the two sets of QA requirements would clearly distinguish
the PSD QA requirements and allow more flexibility for future revisions
to either monitoring program.
    With this proposed rule, the EPA would not change most of the QC
requirements for PSD. Therefore, the discussion that follows will cover
those sections of the PSD requirements that the EPA proposes to change
from the current appendix A requirements.
    The applicability section of appendix B clarifies that the PSD QA
requirements are not assumed to be minimum requirements for data used
in NAAQS decisions. One reason for this distinction is in the
flexibility allowed in PSD monitoring for the NPEP (current appendix A
section 2.4). The proposed PSD requirements allow the PSD reviewing
authority to decide whether implementation of the NPEP will be
performed. The NPEP, which is described in appendix A, includes the
NPAP, PM2.5 Performance Evaluation Program
(PM2.5-PEP), and the Pb-PEP. Accordingly, under the proposed
rule, if a PSD reviewing authority were to have the intent of using PSD
data for any official comparison to the NAAQS beyond the permitting
application, such as for attainment/nonattainment designations or clean
data determinations, then all requirements in appendix B including
implementation of the NPEP would apply. In this case, monitoring would
more closely conform to the appendix A requirements. The EPA proposes
this flexibility for PSD because the NPEP requires either federal
implementation or implementation by a qualified individual, group or
organization that is not part of the organization directly performing
and accountable for the work being assessed. The NPEP may require
specialized equipment, certified auditors and a number of activities
which are enumerated in the sections associated with these programs.
Arranging this type of support service may be more difficult for the
operator of a single or small number of PSD monitoring stations
operating for only a year or less.
    The EPA cannot accept funding from private contractors or industry,
and federal implementation of the NPEP for PSD would face several
funding and logistical hurdles. This creates an inequity in the NPEP
implementation options available to the PSD monitoring organizations
compared to the state/local/tribal monitoring organization monitoring
for NAAQS compliance. The EPA has had success in training and
certifying private contractors in various categories of performance
evaluations conducted under NPEP, but many have not made the necessary
investments in capital equipment to implement all categories of the
performance evaluations. Since the monitoring objectives for the
collection of data for PSD are not necessarily the same as those for
NAAQS evaluations, the EPA proposes to allow the PSD reviewing
authority to determine whether a PSD monitoring project must implement
the NPEP.
    The EPA proposes to clarify the definition of PSD PQAO. The PQAO
was first defined in appendix A in 2006 (current appendix A section
3.1.1) when the PSD requirements were combined with appendix A. The
definition is not substantially changed for PSD, but the EPA proposes
to clarify that a PSD PQAO can only be associated with one PSD
reviewing authority. Distinguishing among the PSD PQAOs that coordinate
with a PSD reviewing authority would be consistent with discrete
jurisdictions for PSD permitting, and it would simplify oversight of
the QA requirements for each PSD network.

    Given that companies may apply for PSD permits throughout the
United States, it is expected that some PSD monitoring organizations
will work with multiple reviewing authorities. The PSD PQAO code which
may appear in the AQS data base and other records defines the PSD
monitoring organization or a coordinated aggregation of such
organizations that is responsible for a set of stations within one PSD
reviewing authority that monitors the same pollutant and for which data
quality assessments will be pooled. The PSD monitoring organizations
that work with multiple PSD reviewing authorities would have individual
PSD PQAO codes for each PSD reviewing authority. This approach will
allow for the flexibility to develop appropriate quality systems for
each PSD reviewing authority.
    The EPA proposes to add definitions of ``PSD monitoring
organization'' and ``PSD monitoring network'' to 40 CFR 58.1. The
definitions have been developed to improve understanding of the
appendix B regulations.
    Since the EPA uses the term ``monitoring organization'' quite
frequently in the NAAQS associated ambient air regulations, the EPA
wants to provide a better definition of the term in the PSD QA
requirements. Therefore, the EPA proposes the term ``PSD monitoring
organization'' to identify ``a source owner/operator, a government
agency, or its contractor that operates an ambient air pollution
monitoring network for PSD purposes.''
    The EPA also proposes to define ``PSD monitoring network'' in order
to distinguish ``a set of monitors that provide concentration
information for a specific PSD permit.'' The EPA will place both
definitions in 40 CFR 58.1.
2. Quality System Requirements
    The EPA proposes to remove the PM10-2.5 requirements for
flow rate verifications, semi-annual flow rate audits, collocated
sampling procedures and PM10-2.5 Performance Evaluation
Program from appendix B (current appendix A sections 3.2.6, 3.2.8,
3.3.6, 3.3.8, 4.3). In 2006, the EPA proposed a PM10-2.5
NAAQS along with requisite QA requirements in appendix A. While the
PM10-2.5 NAAQS was not promulgated, PM10-2.5
monitoring was required to be performed at NCore sites and the EPA
proposed requisite QA requirements in appendix A. Since PSD monitoring
is distinct from monitoring at NCore sites and PM10-2.5 is
not a criteria pollutant, it will be removed from the PSD QA
requirements.
    The EPA proposes that the Pb QA requirements of collocated sampling
(current appendix A section <IP_ADDRESS>) and Pb performance evaluation
procedures (current appendix A section <IP_ADDRESS>) for non-source oriented
NCore sites be eliminated for PSD. The 2010 Pb rule in 40 CFR part 58,
appendix D, section 4.5(b), added a requirement to conduct non-source
oriented Pb monitoring at each NCore site in a CBSA with a population
of 500,000 or more. Since PSD does not implement NCore sites, the EPA
proposes to eliminate the Pb QA language specific to non-source NCore
sites from PSD while retaining the PSD QA requirements for routine Pb
monitoring.
    The EPA proposes that elements of QMPs and QAPPs which are separate
documents and are described in appendix A, sections 2.1.1 and 2.1.2,
can be combined into a single document for PSD monitoring networks. The
QMP provides a ``blueprint'' of a PSD monitoring organization's quality
system. It includes quality policies and describes how the organization
as a whole manages and implements its quality system regardless of what
monitoring is being performed. The QAPP includes details for
implementing a specific PSD monitoring activity. For PSD monitoring,
the EPA believes the project-specific QAPP takes priority but there are
important aspects of the QMP that could be incorporated into the QAPP.
The current appendix A requirements allow smaller organizations or
organizations that do infrequent work with EPA to combine the QMP with
the QAPP based on negotiations with the funding agency and provided
guidance \28\ on a graded approach to developing these documents. In
the case of PSD QMPs and QAPPs, the EPA proposes that the PSD reviewing
authority, which has the approval authority for these documents, also
have the flexibility for allowing the PSD PQAO to combine pertinent
elements of the QMP into the QAPP rather than requiring the submission
of both QMP and QAPP documents separately.
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    \28\ Graded approach to Tribal QAPP and QMPs http://www.epa.gov/ttn/amtic/cpreldoc.html.
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    The EPA proposes to add language to the appendix B version of the
data quality objectives (DQO) section (current appendix A section
2.3.1) which allows flexibility for the PSD reviewing authority and the
PSD monitoring organization to determine if adherence to the DQOs
specified in appendix A, which are the DQO goals for NAAQS decisions,
are appropriate or whether project-specific goals are necessary.
Allowing the PSD reviewing authority and the PSD monitoring
organization flexibility to change the DQOs does not change the
implementation requirements for the types and frequency of the QC
checks in appendix B, but does give some flexibility in the acceptance
of data for use in specific projects for which the PSD data are
collected. As an example, the goal for acceptable measurement
uncertainty for the collection of O3 data for NAAQS
determinations is defined for precision as an upper 90 percent
confidence limit for CV of seven percent and for bias as an upper 95
percent confidence limit for the absolute bias of seven percent. The
precision and bias estimates are made with 3 years of one-point QC
check data. A single or a few one-point QC checks over seven percent
would not have a significant effect on meeting the DQO goal. The PSD
monitoring DQO, depending on the objectives of the PSD monitoring
network, may require a stricter DQO goal or one less restrictive. Since
PSD monitoring covers a period of 1 year or less, one-point QC checks
over seven percent will increase the likelihood of failing to meet the
DQO goal since there would be fewer QC checks available in the
monitoring period to estimate precision and bias. With fewer checks,
any individual check will statistically have more influence over the
precision or bias estimate. Realizing that PSD monitoring may have
different monitoring objectives, the EPA proposes to add language that
would allow decisions on data quality objectives to be determined
through consultation between the appropriate PSD reviewing authority
and PSD monitoring organization.
    The EPA proposes to add some clarifying language to the section
describing the NPEP (current appendix A section 2.4) to explain self-
implementation of the performance evaluation by the PSD monitoring
organization. Self-implementation of NPEP has always been an option for
monitoring organizations but the requirements for self-implementation
were described in the technical implementation documents (i.e.,
implementation plans and QAPPs) for the program and in an annual self-
implementation decision memo that is distributed to monitoring
organizations.\29\ These major requirements for self-implementation are
proposed to be included in the appendix B sections pertaining to the
NPEP program (NPAP, PM2.5-PEP and Pb-PEP).
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    \29\ http://www.epa.gov/ttn/amtic/npepqa.html.
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    The NPEP clarification also adds a definition of ``independent
assessment.''

The proposed definition is derived from the NPEP (NPAP,
PM2.5-PEP, and Pb-PEP) QAPPs and guidance; it also appears
in the annual self-implementation memo described above. The
clarification is not a new requirement but consolidates this
information.
    The EPA proposes to require PSD PQAOs to provide information to the
PSD reviewing authority on the vendors of gas standards that they use
(or will use) for the duration of the PSD monitoring project. A QAPP or
monitoring plan may incorporate this information; however, that
document must then be updated if there is a change in the vendor used.
The current regulation (current appendix A section 2.6.1) requires any
gas vendor advertising and distributing ``EPA Protocol Gas'' to
participate in the AA-PGVP. The EPA posts a list of these vendors on
the AMTIC Web site.\30\ This is not expected to be a burden since
information of this type is normally included in a QAPP or standard
operating procedure for a monitoring activity.
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    \30\ http://www.epa.gov/ttn/amtic/aapgvp.html.
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3. Quality Control Checks for Gases
    The EPA proposes to lower the audit concentrations (current
appendix A section 3.2.1) of the one-point QC checks to 0.005 and 0.08
ppm for SO2, NO2, and O3 (currently
0.01 to 0.1 ppm), and to between 0.5 and 5 ppm for CO monitors
(currently 1 and 10 ppm). With the development of more sensitive
monitoring instruments with lower detection limits, technical
improvements in calibrators, and lower ambient air concentrations in
general, the EPA believes this revision will better reflect the
precision and bias of the routinely-collected ambient air data. Since
the audit concentrations are selected using the mean or median
concentration of typical ambient air data (guidance on this is provided
in the QA Handbook \31\), the EPA is proposing to add some
clarification to the current language by requiring PSD monitoring
organizations to select either the highest or lowest concentration in
the ranges identified if the mean or median values of the routinely-
collected concentrations are above or below the prescribed range. There
is no additional burden added by this requirement since the frequency
is the same and the audit concentrations are not so low as to make them
unachievable to generate or measure.
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    \31\ QA Handbook for Air Pollution Measurement Vol. II Ambient
Air Quality Monitoring Program at: http://www.epa.gov/ttn/amtic/qalist.html.
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    The EPA proposes to remove the existing reference to zero and span
adjustments (current appendix A, section <IP_ADDRESS>) and to revise the
one-point QC language to simply require that the QC check be conducted
before making any calibration or adjustment to the monitor. Recent
revisions of the QA Handbook discourage the practice of making frequent
span adjustments so the proposed language helps to clarify that no
adjustment be made prior to implementation of the one-point QC check.
    The current annual performance evaluation language (current
appendix A, section <IP_ADDRESS>) requires that the audits be conducted by
selecting three consecutive audit levels (currently appendix A
recognizes five audit levels). Due to the implementation of the NCore
network, the inception of trace gas monitors, and lower ambient air
concentrations being measured under typical circumstances, there is a
need for audit levels at lower concentrations to more accurately
represent the uncertainties present in the ambient air data. The EPA
proposes to expand the audit levels from five to ten and remove the
requirement to audit three consecutive levels. The current regulation
also requires that the three audit levels should bracket 80 percent of
the ambient air concentrations measured by the analyzer. This current
``bracketing language'' has caused some confusion and monitoring
organizations have requested the use of an audit point to establish
monitor accuracy around the NAAQS levels. Therefore, the EPA is
proposing to revise the language so that two of the audit levels
selected represent 10 to 80 percent of routinely-collected ambient
concentrations either measured by the monitor or in the PSD PQAOs
network of monitors. The proposed revision allows the third point to be
selected at a concentration that is consistent with PSD-specific DQOs
(e.g., the 75 ppb NAAQS level for SO2).
    The EPA proposes to revise the language (current appendix A,
section <IP_ADDRESS>(a)) addressing the limits on excess NO that must be
followed during GPT procedures involving NO2 audits. The
current NO limit (maintaining at least 0.08 ppm) is very restrictive
and requires auditors to make numerous mid-audit adjustments during a
GPT that result in making the NO2 audit a very time
consuming procedure. Monitoring agency staff have advised us that the
observance of such excess NO limits has no apparent effect on
NO2 calibrations being conducted with modern-day GPT-capable
calibration equipment and, therefore, that the requirements in the
context of performing audits is unnecessary.\32\ We also note the
increasing availability of the EPA-approved direct NO2
methods that do not utilize converters, rendering the use of GPT
techniques that require the output of NO and NOX to be a
potentially diminishingly used procedure in the future. Accordingly, we
have proposed a more general statement regarding GPT that acknowledges
the ongoing usage of monitoring agency procedures and guidance
documents that have successfully supported NO2 calibration
activities. The EPA believes that if such procedures have been
successfully used during calibrations when instrument adjustments are
potentially being made, than such procedures are appropriate for audit
use when instruments are not subject to adjustment. The EPA solicits
comment on this proposed generalization of the GPT requirements,
including whether a more specific set of requirements similar to the
current excess NO levels can be developed based on operational
experience and/or peer reviewed literature.
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    \32\ See supporting information in Excess NO Issue paper, Mike
Papp and Lewis Weinstock, Docket number EPA-HQ-OAR-2013-0619.
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    The EPA proposes to remove language (current appendix A section
<IP_ADDRESS>(b)) in the annual performance evaluation section that requires
regional approval for audit gases for any monitors operating at ranges
higher that 1.0 ppm for O3, SO2 and
NO2 and greater than 50 ppm for CO. The EPA does not need to
approve a monitoring organization's use of audit gases to audit above
proposed concentration levels since the EPA has identified the
requirements for all audit gases used in the program in current
appendix A, section 2.6.1. There should be very few cases where a
performance evaluation needs to be performed above level 10 but there
may be some legitimate instances (e.g., an SO2 audit in
areas impacted by volcanic emissions). Since data reported to AQS above
the highest level may be rejected (if PSD PE data are reported to AQS),
the EPA proposes that PQAOs notify the PSD reviewing authority of sites
auditing at concentrations above level 10 so that reporting
accommodations can be made.
    The EPA proposes to describe the NPAP (current appendix A, section
2.4) in more detail. The NPAP is a long-standing program for the
ambient air monitoring community. The NPAP is a performance evaluation
which is a type of audit where quantitative data are collected
independently in order to evaluate the proficiency of an analyst,
monitoring instrument or laboratory.

This program has been briefly mentioned in section 2.4 of the current
appendix A requirements. In appendix A, the EPA is proposing to add
language consistent with an annual decision memorandum \33\ distributed
to all state and local monitoring organizations in order to determine
whether the monitoring organization plans to self-implement the NPAP
program or utilize the federally implemented program. In order to make
this decision, the NPAP adequacy and independence requirements are
described in the decision memorandum. The EPA proposes to include these
same requirements in appendix B in a separate section for NPAP. As
described in the applicability section, the implementation of NPAP is
at the discretion of the PSD reviewing authority but must be
implemented if data are used in any NAAQS determinations. Since PSD
monitoring is implemented at shorter intervals (usually a year) and
with fewer monitors, if NPAP is performed, it is required to be
performed annually on each monitor operated in the PSD network.
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    \33\ http://www.epa.gov/ttn/amtic/files/ambient/pm25/qa/npappep2014.pdf.
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4. Quality Control Checks for Particulate Monitors
    The EPA proposes to have one flow rate verification frequency
requirement for all PM PSD monitors. The current regulations (current
appendix A, table A-2) provides for monthly flow rate verifications for
most samplers used to monitor PM2.5, PM10 and Pb
and quarterly flow rate verifications for high-volume PM10
or TSP samplers (for Pb). With longer duration NAAQS monitoring, the
quarterly verification frequencies are adequate for these high-volume
PM10 or TSP samplers. However, with the short duration of
PSD monitoring, the EPA believes that monthly flow rate verifications
are more appropriate to ensure that any sampler flow rate problems are
identified more quickly and to reduce the potential for a significant
amount of data invalidation that could extend monitoring activities.
    The EPA proposes to grant more flexibility to PSD monitoring
organizations when selecting PM2.5 method designations for
sites that require collocation. Appendix A currently (current appendix
A, section <IP_ADDRESS>(b)) requires that if a primary monitor is a FEM,
then the first QC collocated monitor must be a FRM monitor. Most of the
FEM monitors are continuous monitors while the FRM monitors are filter-
based. Continuous monitors (which are all FEMs) may be advantageous for
use at the more remote PSD monitoring locations, since the site
operator would not need to visit a site as often to retrieve filters
(current FRMs are filter-based). The current collocation requirements
for FEMs require a filter-based FRM for collocation which would mean a
visit to retrieve the FRM filters at least one week after the QC
collocated monitor operated. Therefore, the EPA proposes that the FRM
be selected as the QC collocated monitor unless the PSD PQAO submits a
waiver request to allow for collocation with a FEM to the PSD reviewing
authority. If the request for a waiver is approved, then the QC monitor
must be the same method designation as the primary FEM monitor.