postings and identified 30-days as an often cited timeframe for public
comment on a draft exceptional events demonstration submittal.
    The current rule also provides at 40 CFR 50.14(c)(3)(iv) that the
demonstration to justify data exclusion shall provide evidence that the
event satisfies the definition of an exceptional event provided at 40
CFR 50.1(j); that there is a clear causal relationship between the
monitored exceedance and the event that is claimed to have affected the
air quality in the area; that the event is associated with a measured
concentration in excess of normal historical fluctuations, including
background; and that there would have been no exceedance or violation
but for the event. Air agencies have found this section of the 2007
Exceptional Events Rule to be confusing because it contains a mix of
statutory requirements and regulatory language without clearly
identifying the components that the EPA expects to see in an
exceptional events demonstration. As the EPA expressed in the Interim
Exceptional Events Implementation Guidance, all parties would benefit
from clear expectations regarding demonstration components.
    The EPA further believes, and recommended in the Interim High Winds
Guidance document, that each demonstration begin with a conceptual
model, or narrative, describing the event(s) causing the exceedance or
violation and a discussion of how emissions from the event(s) led to
the exceedance at the affected monitor(s). As described in the Interim
High Winds Guidance document, the narrative conceptual model could
include varying levels of detail depending on the event complexity, but
in all cases would provide a qualitative description of the event,
interaction of the event-generated emissions with transport and
meteorology (e.g., wind patterns such as strength, convergence,
subsidence, recirculation) and pollutant formation in the area with the
exceeding monitor. Because, in some cases, monitored data or technical
analyses may seem to contradict the event claim, particularly the clear
causal relationship, an air agency can use the conceptual model to
explain, with a weight of evidence approach, why the majority of the
data or analyses are consistent with the event's impact on a measured
exceedance or violation (for example, for a wildfire, why most of the
meteorology would have indicated a lower ozone day without the fire
emissions, even if the temperature were high). A useful conceptual
model also includes (1) a description of the regulatory decision
impacted by the exceptional event, (2) a summary table of the data
requested for exclusion and (3) maps and/or summary tables of event-
related information including location; size and extent; point and
explanation of origin. A conceptual model can additionally include
examples of media coverage of the event.\136\ Since releasing the
Interim High Winds Guidance document in 2013, the EPA has received
several demonstrations that included a conceptual model. The EPA has
found it very helpful to understand the event formation and the event's
influence on monitored pollutant concentrations before beginning to
review the individual technical evidence to support the requested data
exclusion.
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    \136\ The EPA expects that air agencies could use some of the
same information and tables in both the conceptual model and the
Initial Notification of Potential Exceptional Event, which is
discussed in section V.G.5 of this proposal.
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b. Proposed Changes
    For the previously mentioned reasons, the EPA is proposing and
soliciting comment on the following changes to the regulatory language
in 40 CFR 50.14(c)(3) regarding the submission of demonstrations:
     Removing the general schedule provisions in 40 CFR
50.14(c)(3)(i) for submitting demonstrations.
     Moving the language requiring a state to include the
comments it received during the public comment period for the subject
demonstration from 40 CFR 50.14(c)(3)(i) to 40 CFR 50.14(c)(3)(v).
     Modifying the language at 40 CFR 50.14(c)(3)(iv) to more
clearly identify the required elements of an exceptional events
demonstration to include (1) a narrative conceptual model and (2)
demonstrations and analysis that address the core statutory technical
criteria [the event affected air quality in such a way that there
exists a clear causal relationship between the specific event and the
monitored exceedance or violation (as indicated by the comparison to
historical concentrations showing and other analyses), the event was a
human activity that is unlikely to recur at a particular location or
was a natural event, the event was not reasonably controllable or
preventable].
     Modifying the language at 40 CFR 50.14(c)(3)(v) to
identify that a demonstration submittal must include (1) documentation
that the air agency conducted a public comment process on its draft
exceptional events demonstration that was a minimum of 30 days, which
could be concurrent with the EPA's review, (2) any public comments
received during the public comment period and (3) an explanation of how
the air agency addressed the public comments.
    To elaborate on removing the general schedule provisions in 40 CFR
50.14(c)(3)(i), the EPA proposes to remove the provision in 40 CFR
50.14(c)(3)(i) that requires air agencies to submit a demonstration
``not later than the lesser of 3 years following the end of the
calendar quarter in which the flagged concentration was recorded or 12
months prior to the date that a regulatory decision must be made by
EPA.'' In place of this language, the EPA proposes to rely on the
promulgated documentation submission schedule in Table 1 at
50.14(c)(2)(vi) in those cases where the data are to be used in initial
area designations. If the data could influence a regulatory
determination other than initial area designations, the EPA proposes to
rely on the case-by-case timelines established by the reviewing EPA
Regional office as part of the Initial Notification of Potential
Exceptional Event process.
    With respect to the public comment provisions for a developed
demonstration, for the reasons stated previously, the EPA proposes to
move the language requiring an air agency to include the comments it
received during the public comment period for the subject demonstration
from 40 CFR 50.14(c)(3)(i) to 40 CFR 50.14(c)(3)(v) to consolidate the
required elements of the public comment process for exceptional events
demonstrations within a single regulatory provision. The EPA also
proposes to specify a minimum 30-day public comment process, which
provides sufficient time for exchange between the reviewing public and
the

air agency. Shorter comment periods may not provide necessary time for
the public to research the identified event and associated supporting
data while longer timeframes may not be possible where a near-term
regulatory decision relies on an exceptional events decision. The EPA
notes that in very limited cases where the air agency is relying on
exceptional events claims as part of a near-term regulatory action,
such as a demonstration for events in the third year of a 3-year design
value that will be used in initial area designations for a new or
revised NAAQS under a 2-year designation schedule, the public comment
period could be concurrent with the EPA's review provided the
submitting air agency sends any public comments and responses to the
EPA by a specified date should comments be submitted. If an air agency
receives public comment disputing the technical elements of a
demonstration during a comment period that runs concurrent with the
EPA's review and these comments result in the air agency's need to
reanalyze or reassess the validity of a claimed event, a second public
comment period may be necessary.
    The EPA also proposes to revise the language at 40 CFR
50.14(c)(3)(iv) so that it more clearly identifies the required
elements of an exceptional events demonstration. As previously
described, the EPA proposes that each demonstration begin with a
narrative conceptual model, which summarizes the event in question and
provides context for required statutory technical criteria analyses.
The EPA further proposes, consistent with other proposed changes in
this action, that an air agency include in its demonstration to justify
data exclusion evidence that the following statutory technical criteria
are satisfied:
     The event was a human activity that is unlikely to recur
at a particular location or was a natural event.
     The event was not reasonably controllable or preventable.
     The event affected air quality in such a way that there
exists a clear causal relationship between the specific event and the
monitored exceedance or violation (supported in part by the comparison
to historical concentrations and other analyses).
    The EPA seeks comments on the identified proposed changes to the
language at 40 CFR 50.14(c)(3)(i), (iv) and (v), which more clearly
identify the required elements of an exceptional events demonstration.
    The EPA notes that the recent final rule to revise the ozone NAAQS
also removed and reserved the subsequent sections at 40 CFR
50.14(c)(3)(ii) and (iii), which addressed the submittal of exceptional
events demonstrations that could affect regulatory determinations
associated with initial area designations for the 2006 24-hour
PM2.5 NAAQS and the 2010 Lead NAAQS and were made obsolete
by the passage of time. The EPA will retain these removed and reserved
sections as promulgated in the ozone NAAQS and proposes no additional
changes to this language.
7. Timing of the EPA's Review of Submitted Demonstrations
a. Current Situation
    Since promulgation of the Exceptional Events Rule in 2007,
stakeholders have questioned the process by which the EPA reviews
submitted demonstrations.\137\ Specifically, stakeholders have
expressed concern that the EPA has a backlog of submittals but acts
only on EPA-prioritized packages. Stakeholders have stated that because
the EPA has not acted on all submissions, the air quality values used
for planning and regulatory purposes are higher than they would be if
the effects of non-controllable emissions were removed from the data
set. Air agencies have also noted that without feedback, they do not
know the EPA's expectations regarding future submittals.
---------------------------------------------------------------------------

    \137\ See comment letters in Docket ID No. EPA-HQ-OAR-2011-0887
for the July 2012 notice of availability for the Draft Exceptional
Events Implementation Guidance, which the EPA has incorporated into
the record for this action.
---------------------------------------------------------------------------

    The EPA addressed these questions and comments in the Interim
Exceptional Events Implementation Guidance. In Question 27 of the
Interim Q&A document, the EPA identified the general process and timing
for demonstration reviews. In this document, the EPA clarified the
process by which it prioritizes submittals and indicated that we may
not act on submittals with no regulatory significance. The guidance
also presented the voluntary Letter of Intent concept as a mechanism to
aid in planning and prioritization. Additionally, we stated that we
intend to make a decision regarding concurrence with an air agency's
request to exclude data as expeditiously as necessary following
submittal of a complete package if required by a near-term regulatory
action. We also indicated our intent to communicate with the submitting
agency, as needed, during the demonstration review period.
b. Proposed Changes
    In this proposal, the EPA is clarifying some of our previous
statements regarding the prioritization and submittal of
demonstrations. As noted in several subsections within section V.G of
this proposal, we also propose to codify in regulatory language
approaches to increase the efficiency of preparing, submitting and
reviewing exceptional events demonstrations. Although the EPA is not
proposing to codify in regulatory language any changes pertaining to
the timing of the EPA review process, the EPA offers the following
discussion to clarify expectations and facilitate communications, which
are at the center of timing-related issues.
    As noted in the Interim Exceptional Events Implementation Guidance
and in the EPA's best practices discussions described in section IV.E,
the EPA is committed to working with air agencies as they prepare
complete demonstration packages. The EPA encourages ongoing discussions
between the reviewing EPA Regional office and the submitting air agency
from the onset of the Initial Notification of Potential Exceptional
Event process through official package submittal. Since renewing our
focus on improved communications, the EPA has received positive
feedback from engaged agencies that have used this approach.
Additionally, these communications have resulted in decreased instances
of submissions containing insufficient or unnecessary information.
    In reviewing submitted demonstration packages, the EPA will
generally give priority to exceptional events determinations that may
affect near-term regulatory decisions, such as EPA action on SIP
submittals, NAAQS designations and clean data determinations. The EPA
intends to make a decision regarding event status expeditiously
following submittal of a complete package if required by a near-term
regulatory action. If during the review process the EPA identifies the
need for additional information to determine whether the exceptional
events criteria are met, the EPA will notify the submitting air agency
and encourage the agency to provide the supplemental information. If
the information needed is minor and a natural outgrowth of what was
previously submitted, the EPA will not require the air agency to
undergo an additional public notice-and-comment process. However, if
the needed information is significant, the EPA may request that the air
agency re-notice the demonstration before resubmitting it to the EPA,
thus requiring an additional

EPA review following resubmittal. The EPA will work with air agencies
on supplemental timeframes; however, the mandatory timing of the EPA
actions may limit the response time the EPA allows. The EPA proposes to
include as rule text a requirement for the air agency to submit
additional information within 12 months. If additional information is
not received in 12 months, then the EPA will consider the submitted
demonstration inactive, and will not continue the review or take
action. In effect, an air agency's lack of response within a 12-month
period will ``void'' the submittal. In these cases, the EPA does not
intend to issue a formal notice of deferral. If the air agency later
decides to pursue the exceptional events claim after a 12-month period
of inactivity, it may re-initiate the exceptional events process by
submitting a new Initial Notification of Potential Exceptional Event
followed by a new demonstration, which could simply be revising the
original submittal to include the additional information previously
requested by the EPA.
    At the conclusion of the EPA's review, the EPA will make a
determination regarding the status of a submitted exceptional events
demonstration. The EPA's decision could result in concurrence,
nonconcurrence or deferral.\138\ In acting on a submitted demonstration
covering multiple event days and/or multiple flags, the EPA could
concur with part of a demonstration and nonconcur or defer other
flagged values. If the EPA determines that the events addressed in an
exceptional events demonstration are not anticipated to affect any
future regulatory decision, the EPA could defer review of these events
and notify the submitting agency if a subsequent review results in a
determination that the events do affect a regulatory decision.\139\
Formal mechanisms for deferral could include the EPA's indicating this
decision by letter, by email to a responsible official or during a
high-level meeting with an attendees' list and discussion summary.
---------------------------------------------------------------------------

    \138\ The EPA anticipates a reduced number of deferrals and/or
nonconcurrences for demonstrations associated with the Initial
Notification of Potential Exceptional Event process as discussed in
section V.G.5 because the EPA and the affected air agency would have
discussed issues/concerns prior to the EPA's decision on a submitted
demonstration.
    \139\ Routine status calls between the reviewing EPA Regional
office and air agencies could include an agenda item to review the
status of all submitted demonstrations, including those that the EPA
has deferred.
---------------------------------------------------------------------------

8. Dispute Resolution Mechanisms
    Since promulgation of the 2007 Exceptional Events Rule and through
the development of the Interim Exceptional Events Implementation
Guidance, some interested parties have asked the EPA to identify a
process by which submitting air agencies can formally dispute the EPA's
decision regarding requests for additional information to support
submitted demonstration packages and/or decisions regarding
concurrence, nonconcurrence or deferral of submitted demonstration
packages. While the EPA acknowledges the expressed concerns and desire
for a formally identified dispute resolution process, the EPA also
believes that several mechanisms currently exist that air agencies can
use at various points in the exceptional events process. These
mechanisms include engaging in early dialogue with the reviewing EPA
Regional office, submitting requests for reconsideration to the
official who made the determination if a request identifies a clear
error or if the reviewing EPA regional office overlooked information
submitted by the affected air agency, and/or elevating the concern
within the EPA's chain of command. Additionally, air agencies can raise
any unresolved event-related issues during the regulatory process that
relies upon the claimed event-influenced data by participating in
related public notice-and-comment processes and/or challenging in an
appropriate court the regulatory decision subsequently made based in
part on the EPA's exceptional events determination. These currently
available dispute resolution approaches to address exceptional events
decisions are consistent with the mechanisms available for other EPA
actions. With exceptional events decisions, however, the air agency has
opportunities to elevate concerns during two processes: the exceptional
events determination and the subsequent regulatory action that relies
on the exceptional events decision.
    The EPA believes that the existing mechanisms identified above
combined with the EPA's commitment to focus on communication and
collaboration with the submitting air agency through the exceptional
events demonstration process, and the clarifications that would be in
effect with these proposed revisions to the 2007 Exceptional Events
Rule and associated guidance, will avoid the need for a formal dispute
resolution mechanism for exceptional events. Therefore, the EPA does
not intend to address dispute resolution within these proposed rule
revisions and does not intend to respond to comments on this issue.

VI. Mitigation

A. Current Situation

    Section 319(b)(3)(A) of the CAA identifies five principles for the
EPA to follow in developing implementing regulations for exceptional
events:
    (i) Protection of public health is the highest priority;
    (ii) Timely information should be provided to the public in any
case in which the air quality is unhealthy;
    (iii) All ambient air quality data should be included in a timely
manner in an appropriate federal air quality database that is
accessible to the public;
    (iv) Each state must take necessary measures to safeguard public
health regardless of the source of the air pollution; and
    (v) Air quality data should be carefully screened to ensure that
events not likely to recur are represented accurately in all monitoring
data and analyses.
    The regulatory requirements implementing (iii) and (v) of this part
of the statute are found only in 40 CFR 50.14 while the regulatory
requirements implementing (i) and (iv) are found only in 40 CFR 51.930,
Mitigation of Exceptional Events. Both Sec. Sec.  50.14(c)(1) and
51.930(a)(1) require states to provide notice of events to the public
(the second of the five principles).
    The language at 40 CFR 51.930 requires air agencies requesting data
exclusion to ``take appropriate and reasonable actions to protect
public health from exceedances or violations of the NAAQS'' and at a
minimum do each of the following:
     Provide for prompt public notification whenever air
quality concentrations exceed or are expected to exceed the NAAQS.
     Provide for public education concerning actions that
individuals may take to reduce exposures to unhealthy levels of air
quality during and following an exceptional event.
     Provide for the implementation of appropriate measures to
protect public health from exceedances or violations of ambient air
quality standards caused by exceptional events.
    The EPA promulgated the existing requirements in 2007 after
considering and proposing several approaches to implementing CAA
section 319(b)(3)(A). Some of the proposed approaches would have
established a more formal structure by which air agencies prepared and
submitted to the EPA mitigation plans to protect public health during
events. These plans would have

been subject to the EPA's approval and/or the approval of the exclusion
of event-affected data would have been contingent on the approval of
such a plan. Comments on these proposed options varied
widely.140 141
---------------------------------------------------------------------------

    \140\ The Treatment of Data Influenced by Exceptional Events;
Proposed Rule, 71 FR 12592 (March 10, 2006).
    \141\ See Comments and Responses related to ``Requirements for
States To Provide Public Notification, Public Education, and
Appropriate and Reasonable Measures To Protect Public Health'' in
Treatment of Data influenced by Exceptional Events; Final Rule, 72
FR 13574-13576 (March 22, 2007).
---------------------------------------------------------------------------

    In the final 2007 Exceptional Events Rule, ``mitigation'' measures
\142\ became part of the 2007 Exceptional Events Rule, but they were
not incorporated into the criteria and processes by which data are
excluded from use in regulatory determinations. There is no requirement
to submit such measures to the EPA for either prospective or
retrospective review and approval as a condition for approval for
exclusion of event-affected data. Neither are air agencies required to
notify the EPA of the measures an air agency plans to take or has
taken. In the preamble to the 2007 Exceptional Events Rule, we stated
that states should take ``reasonable and appropriate measures'' to
protect public health related to the occurrence of an event and that
states should determine what measures constitute those that are
``reasonable and appropriate.'' \143\ We did not clarify how measures
should be determined to be ``appropriate'' measures.
---------------------------------------------------------------------------

    \142\ The term ``mitigation'' does not appear in CAA section
319(b). It appears in the title but not the text of 40 CFR 51.930.
    \143\ 72 FR 13574 (March 22, 2007).
---------------------------------------------------------------------------

    The mitigation measures that the EPA sees states most commonly
practicing are ones related to the requirement that air agencies
``provide for prompt public notification whenever air quality
concentrations exceed or are expected to exceed the NAAQS.'' Often,
these public notifications include public health alerts for high wind
dust events or wildfires. We believe that other aspects of mitigation,
including implementing appropriate measures to protect public health
beyond notification, are also important in implementing the CAA guiding
principle that ``each State must take necessary measures to safeguard
public health regardless of the source of the air pollution.''

B. Proposed Changes

    Given the EPA's and the states' experience implementing the 2007
Exceptional Events Rule as indicated above, we consider it appropriate
to consider possible changes to the mitigation-related rule components
with the benefit of additional public input. We are seeking comment on
approaches ranging from retaining the existing rule requirements at 40
CFR 51.930 to the various possible new components described in this
section. We invite comment on these alternatives and on other concepts.
We may make no change; we may adopt all of the described new
components; or we may adopt only some features or variations of the
described options. Note that we are not considering requiring all
states to develop formal mitigation plans. We are seeking comment on
the concept of only some states being required to develop mitigation
plans for their particular ``historically documented'' or ``known
seasonal'' exceptional events, defined below in section VI.B.1; on
recommended elements for such mitigation plans described below in
section VI.B.2; and on options for implementing mitigation plans
described in section VI.B.3. Section VI.B.4 summarizes the EPA's
potential options for mitigation elements for exceptional events
purposes.
1. Defining Historically Documented or Known Seasonal Events
    The EPA seeks comment on whether an air agency should develop a
mitigation plan for its particular type of ``historically documented''
or ``known seasonal'' exceptional events, if any. The EPA would
consider ``historically documented'' or ``known seasonal'' exceptional
events to include events of the same type and pollutant (e.g., high
wind dust/PM or wildfire/ozone) that meet any of the following
criteria: an event for which an air agency has previously submitted
exceptional events demonstrations; an event that an air agency has
previously flagged for concurrence in AQS (regardless of whether the
air agency submitted a demonstration); or an event that has been the
subject of local news articles, public health alerts or published
scientific journal articles. The EPA would not require an air agency to
develop a mitigation plan for the first event of a given type (e.g., if
an area is prone to wildfires but has never experienced a high wind
dust event, then it would not be expected to develop a mitigation plan
for its first high wind dust event, but it would be expected to develop
a mitigation plan for wildfires). A second event of a given type within
a 3-year period would subject the area to ``having a history'' and,
therefore, needing a mitigation plan.\144\ This option avoids plan
development for a one-of-a-kind occurrence.\145\ In defining ``first''
and ``second'' events, the EPA could consider events that affect the
same AQCR, but not necessarily the same monitor.\146\ For example, high
wind dust events occur seasonally in the Phoenix, Arizona metropolitan
area, which is part of the Maricopa Intrastate Air Quality Control
Region (see 40 CFR 81.36). These events have influenced particulate
matter concentrations at multiple monitors within the Maricopa
Intrastate AQCR. Under this proposal, high wind dust events in Phoenix
(i.e., the Maricopa Intrastate AQCR) are known events requiring a
mitigation plan. On the other hand, a high wind dust event in Sedona,
Arizona, part of the Northern Arizona Intrastate Air Quality Control
Region (see 40 CFR 81.270), would be a first event and not subject to
the development of a mitigation plan. As a variation of this concept on
which we also seek comment, the EPA could consider a first season of
events as one of three required seasons of events, so that a mitigation
plan would be required only when an event type persists across several
years. For example, an area may not have previously experienced
wildfires in the past 10 years, but then experiences multiple wildfires
and multiple exceedances in a single wildfire season. If these multiple
wildfires affect the same general geographic area and monitors in a
relatively short period of time (e.g. 2-3 months), then they could be
considered a single event for purposes of developing a mitigation plan
and would not trigger the requirement for a mitigation plan.
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    \144\ A 3-year period is determined based on the submittal date
of an exceptional events demonstration.
    \145\ Because the form of the NAAQS varies by pollutant, it is
possible that multiple events in a 3-year period may not cause a
NAAQS violation. An air agency that identifies multiple events of
the same type (e.g., wildfire/ozone) in AQS, but prepares and
submits a demonstration for only one of these events, would trigger
the proposed requirement to develop a mitigation plan.
    \146\ Air Quality Control Regions are defined in 40 CFR part 81,
subpart B, Designation of Air Quality Control Regions.
---------------------------------------------------------------------------

2. Mitigation Plan Components
    The EPA solicits comment on the following three plan components
that could be recommended or required in order to implement the
mitigation principles found in section 319(b)(3)(A) of the CAA: Public
notification and education; steps to identify, study and implement
mitigating measures and provision for periodic revision of the
mitigation plan (to include public

review of plan elements). This section discusses these elements in more
detail. A mitigation plan should address actions that would be taken
within a state's own territory for events that happen within its own
territory or that of another jurisdiction.
    a. Public notification to and education programs for affected or
potentially affected communities. Air agencies could be required or
encouraged to include in their mitigation plans steps to activate
public notification and education systems whenever air quality
concentrations exceed or are expected to exceed an applicable national
ambient air quality standard. If possible, air agencies would notify
the public of the actual or anticipated event at least 48 hours in
advance of the event using methods appropriate to the community being
served. Outreach mechanisms could include Web site alerts, National
Weather Service alerts, telephone or text bulletins, television or
radio campaigns or other messaging campaigns. Public notification and
education programs could be encouraged or required to include some or
all of the following actions to support the outreach system: adoption
of methods for forecasting/detection, consultation with appropriate
health department personnel regarding issuing health advisories and
suggested actions for exposure minimization for sensitive populations
(e.g., remain indoors, avoid vigorous outdoor activity, avoid exposure
to tobacco smoke and other respiratory irritants and, in extreme cases,
evacuation or public sheltering procedures).
    b. Steps to identify, study and implement mitigating measures,
including approaches to address each of the following:
    (i) Mandatory or voluntary measures to abate or minimize
contributing controllable sources of identified pollutants. A state
could be required to include or encouraged to consider full-time or
contingent controls on event-related sources as well as non-event
related sources. For example, these measures might include continuously
operating control measures during an extreme event for identified
sources that normally operate these same controls on an intermittent
basis. It could also involve including work practices (e.g., water
spray for dust suppression) or contingent limits during extreme events
on emissions from non-event related sources that, under non-event
periods, have no or less stringent emissions limits or work practices.
    (ii) Methods to minimize public exposure to high concentrations of
identified pollutants.
    (iii) Processes to collect and maintain data pertinent to the event
(e.g., to identify the data to be collected, the party responsible for
collecting and maintaining the data and when, how and to whom the data
will be reported).
    (iv) Mechanisms to consult with other air quality managers in the
affected area regarding the appropriate responses to abate and minimize
impacts. Consultation could include collaboration between potentially
affected local, state, tribal and federal air quality managers and/or
emergency response personnel.
    c. Provision for periodic review and evaluation of the mitigation
plan and its implementation and effectiveness by the air agency and all
interested stakeholders (e.g., public and private land owners/managers,
air quality, agriculture and forestry agencies, the public). For
example, air agencies could be required to use this review process and
to revise, if appropriate, and certify the mitigation plan every 3
years or every three events, whichever is longer. The air agency could
be required to submit a summary and response to the comments received
during the public plan review process to the EPA along with the
recertification statement and/or revised mitigation plan. If the
historically documented or known seasonal exceptional events continue
to result in elevated pollutant concentrations above the relevant
NAAQS, thus showing that the combination of the existing SIP and the
existing mitigation plan does not effectively safeguard public health,
the mitigation plan might need to be strengthened during this review.
    If the EPA adopts requirements like those described above, it would
not necessarily mean that all affected air agencies would have to
prepare new plans. If an air agency has developed and implemented a
contingency plan under 40 CFR part 51, subpart H, Prevention of Air
Pollution Emergency Episodes, that meets the requirements of 40 CFR
51.152, and that includes provisions for events that could be
considered ``exceptional events'' under the provisions in 40 CFR 50.14,
then the subpart H contingency plan would likely satisfy the mitigation
requirements described above. If the identified basic elements are
included and addressed, including the element for public comment, then
other types of existing mitigation or contingency plans may satisfy the
possible mitigation plan requirement described above. For example, if
an area has developed a natural events action plan or a high wind
action plan covering high wind dust events, this plan likely would
satisfy mitigation elements for high wind dust events. Smoke management
plans and/or forest management plans might also satisfy the mitigation
elements for prescribed fires and wildfires. Most air agencies
generally have sufficient, established processes that meet the public
notification and education element, which can be easily adapted or
modified to meet the mitigation elements proposed in this action. The
EPA is requesting comment on how much time air agencies should be
allowed to develop a plan.
3. Options for Implementing Mitigation Plans
    The EPA is seeking comment on two options for tying the proposed
mitigation plan components discussed in section VI.B.2 to the EPA
review of exceptional events demonstrations. Option 1 includes the
EPA's review for completeness but not substantive approval or
disapproval, while Option 2 includes the EPA's approval of the
substance of the mitigation plan. These options are discussed below in
more detail, but neither option would require a mitigation plan to be
included in a SIP or to be otherwise federally-enforceable.
    Under both options, air agencies with historically documented or
known seasonal exceptional events could submit the mitigation plan to
the EPA in advance of an event, or submit a mitigation plan along with
an exceptional events demonstration. The EPA would concur with a
demonstration for the relevant event type only if a mitigation plan has
passed the type of EPA review described in the option. Given that the
air agency would have advance notification of the need to develop a
plan, the air agency could develop and submit the mitigation plan in
advance of any exceptional events demonstration so that the EPA could
pre-review the mitigation plan and take faster action on an exceptional
events submittal once one is submitted.
    Option 1: Under this option, the EPA would review for inclusion of
required elements as described above and to ensure that the development
of the mitigation plan included a public comment process. We would not
formally review the substance of the plan in the sense of approving the
details of the specific measures and commitments in the plan.
    Option 2: Under this option, EPA approval of the substance of the
mitigation plan would be a precondition for EPA concurrence on an
exceptional events demonstration. Because the EPA would approve the
content, completeness and sufficiency of a mitigation plan, the EPA's
disapproval

of the plan could result in the EPA's nonconcurrence on a current or
future exceptional events demonstration.

VII. Draft Guidance on the Preparation of Exceptional Events
Demonstrations for Wildfire Events That May Influence Ozone
Concentrations

A. What is this draft guidance about and why is it needed?

    The Exceptional Events Rule contains the regulatory requirements
and criteria necessary for the EPA's approval of the exclusion of air
quality data from regulatory determinations related to NAAQS
exceedances or violations. During the implementation of the 2007
Exceptional Events Rule, the EPA and stakeholders have identified a
need for implementation guidance that provides an interpretation of and
examples for addressing the regulatory requirements specific to the
most common event types. One event type that has been identified by the
EPA and stakeholders is wildfire influence on ozone concentrations. In
2013, the EPA finalized the Interim Exceptional Events Implementation
Guidance documents (see section IV.D), which included the Interim High
Winds Guidance document and an Interim Overview document that also
committed to the preparation of a Draft Wildfire Ozone Guidance
document. The EPA intends to address this need and commitment via the
Draft Guidance on the Preparation of Exceptional Events Demonstrations
for Wildfire Events that May Influence Ozone Concentrations (``Draft
Wildfire Ozone Guidance document''), which accompanies this proposed
rule and is also available for comment.
    This Draft Wildfire Ozone Guidance document includes example
analyses, conclusion statements and technical tools that air agencies
can use to provide evidence that the wildfire event influenced the
monitored ozone concentration. The Draft Wildfire Ozone Guidance
document also identifies fire and monitor-based characteristics that
might allow for a simpler and less resource-consuming demonstration
package. The EPA has developed the Draft Wildfire Ozone Guidance
document concurrently with the proposed Exceptional Events Rule
revisions so that the Draft Wildfire Ozone Guidance reflects the
proposed rule changes. Once finalized, this guidance will provide the
EPA regional offices and air agencies with guidance on how to prepare
and submit evidence to meet the Exceptional Events Rule requirements
for monitored ozone exceedances caused by wildfires. The guidance, when
finalized, will not be an EPA rule, and in specific cases the EPA may
depart from the guidance for reasons that the EPA will explain at the
time of the action.

B. What scenarios are addressed in the draft guidance?

    The EPA has prepared the Draft Wildfire Ozone Guidance document to
provide assistance and example analyses for wildfire events that may
influence ozone concentrations. Though many of the technical analyses
included in the draft document may also be applied to prescribed fire
events, the draft guidance document available for comment at this time
does not provide guidance specific on how prescribed fire events can
address all proposed rule requirements. Limiting the scope to wildfire
events is intended to make the document easier to use for wildfire
events. With this notice, the EPA invites comment on the content of
this guidance document and whether it is appropriate to expand the
scope of the guidance to include prescribed fire events. If commenters
believe it is necessary to expand the scope of the EPA's final new
guidance beyond the scope of the Draft Wildfire Ozone Guidance
document, the EPA seeks comment on whether wildfire and prescribed fire
events should be addressed in a single fire ozone guidance document or
in separate guidance documents.

VIII. Environmental Justice Considerations

    The Exceptional Events Rule provides the criteria by which state,
local and tribal air agencies identify air quality data they believe
have been influenced by exceptional events, which by statutory
definition are not reasonably controllable or preventable. Because
these events are not reasonable to prevent or control, they can affect
all downwind populations including minority and low-income populations.
For this reason, in adding section 319(b) to the CAA, Congress
identified as a guiding principle in developing regulations, ``the
principle that protection of public health is the highest priority.''
The 2007 Exceptional Events Rule at 40 CFR 50.14 requires air agencies
to seek public comment on prepared exceptional events demonstrations
prior to submitting them to the reviewing EPA regional office. The
public can also comment on rulemakings that include decisions related
to the exclusion of event-influenced data. The mitigation of
exceptional events language at 40 CFR 51.930 also requires that air
agencies provide public notification and education programs related to
events. To protect all people and communities, notably minority and
low-income populations, air agencies should ensure that notifications
and education programs are communicated using the language (e.g.,
English and Spanish) and media (e.g., radio and postings in local
community centers) best suited to the target audience(s). Additionally,
these proposed revisions are part of a public notice-and-comment
rulemaking effort, which will include a public hearing. These
opportunities for public input and education ensure that all those
residing, working, attending school or otherwise present in areas
affected by exceptional events, regardless of minority and economic
status, are protected.

IX. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review

    This action is a significant regulatory action that was submitted
to the Office of Management and Budget (OMB) for review because it
raises novel policy issues. Any changes made in response to OMB
recommendations have been documented in the docket.

B. Paperwork Reduction Act

    This action does not impose any new information collection burden
under the PRA. The information being requested under these proposed
rule revisions is consistent with current requirements related to
information needed to verify the authenticity of monitoring data
submitted to the EPA's AQS database, and to justify exclusion of data
that have been flagged as being affected by exceptional events. OMB has
previously approved the information collection activities for ambient
air monitoring data and other supporting measurements reporting and
recordkeeping activities associated with the 40 CFR part 58 Ambient Air
Quality Surveillance rule and has assigned OMB control number 2060-
0084.

C. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic
impact on a substantial number of small entities under the RFA. This
action will not impose any requirements on small entities. Instead, the
proposed rule revisions provide the criteria and increase the
efficiency of the process by which state, local and tribal air agencies
identify air quality data they believe

have been influenced by an exceptional event. The proposed rule
revisions also clarify those actions that state, local and tribal air
agencies should take to protect public health during and following an
exceptional event. Because affected air agencies would have discretion
to implement controls on sources that may need to be regulated due to
anthropogenic contribution in the area determined to be influenced by
an exceptional event, the EPA cannot predict the indirect effect of the
rule on sources that may be small entities.

D. Unfunded Mandates Reform Act (UMRA)

    This action does not contain an unfunded mandate of $100 million or
more as described in UMRA, 2 U.S.C. 1531-1538, and does not
significantly or uniquely affect small governments. The action imposes
no enforceable duty on any state, local or tribal governments or the
private sector.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. The EPA
believes, however, that this action may be of significant interest to
states and to local air quality agencies to whom a state has delegated
relevant responsibilities for air quality management. Consistent with
the EPA's policy to promote communications between the EPA and state
and local governments, the EPA consulted with representatives of state
and local governments early in the process of developing this action to
permit them to have meaningful and timely input into its development. A
summary of the concerns raised during that consultation is provided in
section IV of this preamble.

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

    This action does not have tribal implications as specified in
Executive Order 13175. It would not have a substantial direct effect on
one or more Indian tribes. Furthermore, these proposed regulation
revisions do not affect the relationship or distribution of power and
responsibilities between the federal government and Indian tribes. The
CAA and the TAR establish the relationship of the federal government
and tribes in characterizing air quality and developing plans to attain
the NAAQS, and these revisions to the regulations do nothing to modify
that relationship. Thus, Executive Order 13175 does not apply to this
action.
    Although Executive Order 13175 does not apply to this action, the
EPA held public meetings attended by tribal representatives and
separate meetings with tribal representatives to discuss the revisions
proposed in this action. The EPA also provided an opportunity for all
interested parties to provide oral or written comments on potential
concepts for the EPA to address during the rule revision process.
Summaries of these meetings are included in the docket for this
proposed rule. The EPA specifically solicits additional comment on this
proposed action from tribal officials.

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

    The EPA interprets Executive Order 13045 as applying only to those
regulatory actions that concern environmental health or safety risks
that the EPA has reason to believe may disproportionately affect
children, per the definition of ``covered regulatory action'' in
section 2-202 of the Executive Order. This action is not subject to
Executive Order 13045 because it does not concern an environmental
health risk or safety risk.

H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution or Use

    This action is not a ``significant energy action'' because it is
not likely to have a significant adverse effect on the supply,
distribution or use of energy. The purpose of this proposed rule is to
provide the criteria, and increase the efficiency of the process, by
which state, local and tribal air agencies may identify air quality
data they believe have been influenced by an exceptional event. The EPA
does not expect these activities to affect energy suppliers,
distributors or users.

I. National Technology Transfer and Advancement Act

    This rulemaking does not involve technical standards.

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

    The EPA believes the human health or environmental risk addressed
by this action will not have potential disproportionately high and
adverse human health or environmental effects on minority, low-income
or indigenous populations. The results of this evaluation are contained
in the section of the preamble titled ``Environmental Justice
Considerations.'' This proposed action provides the criteria and
increases the efficiency of the process by which state, local and
tribal air agencies identify air quality data they believe have been
influenced by exceptional events, which, by statutory definition, are
not reasonably controllable or preventable. These proposed regulatory
provisions do, however, provide information concerning actions that
state, local or tribal air agencies might take to uniformly protect
public health once the EPA has concurred with an air agency's request
to exclude data influenced by an exceptional event. The mitigation
component of the proposed rule could ultimately provide additional
protection for minority, low income and other populations located in
areas affected by exceptional events. Therefore, the EPA finds that
this proposed action would not adversely affect the health or safety of
minority or low-income populations, and that it is designed to protect
and enhance the health and safety of these and other populations.

X. Statutory Authority

    The statutory authority for this action is provided by 42 U.S.C.
7401, et seq.

List of Subjects in 40 CFR Part 50

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

    Dated: November 10, 2015.
Gina McCarthy,
Administrator.

    For the reasons set forth in the preamble, it is proposed that 40
CFR part 50 be amended as follows:

PART 50--NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY
STANDARDS

0
1. The authority citation for part 50 continues to read as follows:

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

0
2. Amend Sec.  50.1 by:
0
a. Revising paragraphs (j) and (k).
0
b. Adding paragraphs (m), (n), (o), (p), (q) and (r).
    The revisions and additions read as follows:

Sec.  50.1  Definitions.

* * * * *
    (j) Exceptional event means an event and its resulting emissions
that affect air quality in such a way that there exists a clear causal
relationship between the specific event and the monitored exceedance or
violation, is not reasonably controllable or preventable, is an event
caused by human activity that is unlikely to recur at a particular
location or a natural event, and is determined by the Administrator in
accordance with 40 CFR 50.14 to be an

exceptional event. It does not include stagnation of air masses or
meteorological inversions, a meteorological event involving high
temperatures or lack of precipitation, or air pollution relating to
source noncompliance.
    (k) Natural event means an event and its resulting emissions, which
may recur, in which human activity plays little or no direct causal
role. Anthropogenic sources that are reasonably controlled shall be
considered to not play a direct role in causing emissions.
* * * * *
    (m) Prescribed fire is any fire intentionally ignited by management
actions in accordance with applicable laws, policies, and regulations
to meet specific land or resource management objectives.
    (n) Wildfire is any fire started by an unplanned ignition caused by
lightning; volcanoes; other acts of nature; unauthorized activity; or
accidental, human-caused actions, or a prescribed fire that has been
declared to be a wildfire. A wildfire that predominantly occurs on
wildland is a natural event.
    (o) Wildland means an area in which human activity and development
is essentially non-existent, except for roads, railroads, power lines,
and similar transportation facilities. Structures, if any, are widely
scattered.
    (p) High wind dust event is an event that includes the high-speed
wind and the dust that the wind entrains and transports to a monitoring
site.
    (q) High wind threshold is the minimum wind speed capable of
causing particulate matter emissions from natural undisturbed lands in
the area affected by a high wind dust event.
    (r) Federal land manager means, consistent with the definition in
40 CFR 51.301, the Secretary of the department with authority over the
Federal Class I area (or the Secretary's designee) or, with respect to
Roosevelt-Campobello International Park, the Chairman of the Roosevelt-
Campobello International Park Commission.
0
3. Amend Sec.  50.14, as amended on October 26, 2015, at 80 FR 65452,
effective December 28, 2015, as follows:
0
a. Revise paragraphs (a) and (b);
0
b. Revise paragraphs (c)(1), (c)(2)(i) through (v), and (c)(3).
    The revisions read as follows:

Sec.  50.14  Treatment of air quality monitoring data influenced by
exceptional events.

    (a) Requirements--(1) Scope. (i) This section applies to the
treatment of data showing exceedances or violations of any national
ambient air quality standard for purposes of the following types of
regulatory determinations by the Administrator:
    (A) An action to designate an area, pursuant to Clean Air Act
section 107(d)(1), or redesignate an area, pursuant to Clean Air Act
section 107(d)(3), for a particular national ambient air quality
standard;
    (B) The assignment or re-assignment of a classification category to
a nonattainment area where such classification is based on a comparison
of pollutant design values, calculated according to the specific data
handling procedures in 40 CFR part 50 for each national ambient air
quality standard, to the level of the relevant national ambient air
quality standard;
    (C) A determination regarding whether a nonattainment area has
attained the level of the appropriate national ambient air quality
standard by its specified deadline;
    (D) A determination that an area has had only one exceedance in the
year prior to its attainment deadline and thus qualifies for a 1-year
attainment date extension, if applicable; and
    (E) A determination under Clean Air Act section 110(k)(5), if based
on an area violating a national ambient air quality standard, that the
state implementation plan is inadequate to the requirements of Clean
Air Act section 110.
    (ii) A State, federal land manager or other federal agency may
request the Administrator to exclude data showing exceedances or
violations of any national ambient air quality standard that are
directly due to an exceptional event from use in determinations by
demonstrating to the Administrator's satisfaction that such event
caused a specific air pollution concentration at a particular air
quality monitoring location.
    (A) For a federal land manager or other federal agency to be
eligible to initiate such a request for data exclusion, the federal
land manager or other federal agency must:
    (1) Either operate a regulatory monitor that has been affected by
an exceptional event or manage land on which an exceptional event
occurred that influenced a monitored concentration at a regulatory
monitor; and
    (2) Initiate such a request only after discussing such submittal
with the State in which the affected monitor is located; and
    (B) When initiating such a request, all provisions in this section
that are expressed as requirements applying to a State shall, except as
noted, be requirements applying to the federal land manager or other
federal agency.
    (2) A demonstration to justify data exclusion may include any
reliable and accurate data, but must specifically address the elements
in paragraphs (c)(3)(iv) and (v) of this section.
    (b) Determinations by the Administrator--(1) Generally. The
Administrator shall exclude data from use in determinations of
exceedances and violations where a State demonstrates to the
Administrator's satisfaction that an exceptional event caused a
specific air pollution concentration in excess of one or more national
ambient air quality standards at a particular air quality monitoring
location and otherwise satisfies the requirements of this section.
    (2) Fireworks displays. The Administrator shall exclude data from
use in determinations of exceedances and violations where a State
demonstrates to the Administrator's satisfaction that emissions from
fireworks displays caused a specific air pollution concentration in
excess of one or more national ambient air quality standards at a
particular air quality monitoring location and otherwise satisfies the
requirements of this section. Such data will be treated in the same
manner as exceptional events under this rule, provided a State
demonstrates that such use of fireworks is significantly integral to
traditional national, ethnic, or other cultural events including, but
not limited to, July Fourth celebrations that satisfy the requirements
of this section.
    (3) Prescribed fires. (i) The Administrator shall exclude data from
use in determinations of exceedances and violations, where a State
demonstrates to the Administrator's satisfaction that emissions from
prescribed fires caused a specific air pollution concentration in
excess of one or more national ambient air quality standards at a
particular air quality monitoring location and otherwise satisfies the
requirements of this section.
    (ii) In addressing the requirements set forth in paragraph
(c)(3)(iv)(D) of this section regarding the not reasonably controllable
or preventable criterion:
    (A) With respect to the requirement that a prescribed fire be not
reasonably controllable, the State must either certify to the
Administrator that it has adopted and is implementing a smoke
management plan or the State must demonstrate that the burn manager
employed the generally applicable basic smoke management practices
identified in Table 2 to Sec.  50.14. To make the latter demonstration,
the State may rely on a statement or other documentation provided by
the burn manager that he or she employed those practices. If an
exceptional event occurs using the basic

smoke management practices approach, the State must undertake a review
of its approach to ensure public health is being protected.
    (B) With respect to the requirement that a prescribed fire be not
reasonably preventable, provided the Administrator determines that
there is no compelling evidence to the contrary in the record, the
State may rely upon and reference a multi-year land or resource
management plan for a wildland area with a stated objective to
establish, restore and/or maintain a sustainable and resilient wildland
ecosystem and/or to preserve endangered or threatened species through a
program of prescribed fire, but also provided that the use of
prescribed fire in the area has not exceeded the frequency indicated in
that plan.
    (iii) Provided the Administrator determines that there is no
compelling evidence to the contrary in the record, in addressing the
requirements set forth in paragraph (c)(3)(iv)(E) of this section
regarding the human activity unlikely to recur at a particular location
criterion for demonstrations involving prescribed fires on wildland,
the State must describe the actual frequency with which a burn was
conducted, but may rely upon and reference an assessment of the natural
fire return interval or the prescribed fire frequency needed to
establish, restore, and/or maintain a sustainable and resilient
wildland ecosystem contained in a multi-year land or resource
management plan with a stated objective to establish, restore, and/or
maintain a sustainable and resilient wildland ecosystem and/or to
preserve endangered or threatened species through a program of
prescribed fire.

 Table 2 to Sec.   50.14--Summary of Basic Smoke Management Practices, Benefit Achieved With the BSMP, and When
                         It Is Applied Before, During or After Ignition of the Burn \a\
----------------------------------------------------------------------------------------------------------------
                                         Benefit achieved with the     When the BSMP is  applied--before/during/
   Basic smoke management practice                  BSMP                            after  the burn
----------------------------------------------------------------------------------------------------------------
Evaluate Smoke Dispersion Conditions.  Minimize smoke impacts.......  Before, During, After.
Monitor Effects on Air Quality.......  Be aware of where the smoke    Before, During, After.
                                        is going and degree it
                                        impacts air quality.
Record-Keeping/Maintain a Burn/Smoke   Retain information about the   Before, During, After.
 Journal.                               weather, burn and smoke. If
                                        air quality problems occur,
                                        documentation helps analyze
                                        and address air regulatory
                                        issues.
Communication--Public Notification...  Notify neighbors and those     Before, During.
                                        potentially impacted by
                                        smoke, especially sensitive
                                        receptors.
Consider Emission Reduction            Reducing emissions through     Before, During, After.
 Techniques.                            mechanisms such as reducing
                                        fuel loading can reduce
                                        downwind impacts.
Share the Airshed--Coordination of     Coordinate multiple burns in   Before, During, After.
 Area Burning.                          the area to manage exposure
                                        of the public to smoke.
----------------------------------------------------------------------------------------------------------------
\a\ Elements of these BSMP could also be practical and beneficial to apply to wildfires for areas likely to
  experience recurring wildfires.

    (4) Wildfires. The Administrator shall exclude data from use in
determinations of exceedances and violations where a State demonstrates
to the Administrator's satisfaction that emissions from wildfires
caused a specific air pollution concentration in excess of one or more
national ambient air quality standard at a particular air quality
monitoring location and otherwise satisfies the requirements of this
section. Provided the Administrator determines that there is no
compelling evidence to the contrary in the record, the Administrator
will determine every wildfire occurring predominantly on wildland to
have met the requirements identified in paragraph (c)(3)(iv)(D) of this
section regarding the not reasonably controllable or preventable
criterion.
    (5) High wind dust events. (i) The Administrator shall exclude data
from use in determinations of exceedances and violations, where a State
demonstrates to the Administrator's satisfaction that emissions from a
high wind dust event caused a specific air pollution concentration in
excess of one or more national ambient air quality standards at a
particular air quality monitoring location and otherwise satisfies the
requirements of this section provided that such emissions are from high
wind dust events.
    (ii) The Administrator will consider high wind dust events to be
natural events in cases where windblown dust is entirely from
undisturbed natural lands or where all anthropogenic sources are
reasonably controlled as determined in accordance with paragraph (b)(7)
of this section.
    (iii) The Administrator will accept a high wind threshold of a
sustained wind of 25 mph for areas in the States of Arizona,
California, Colorado, Kansas, Nebraska, Nevada, New Mexico, North
Dakota, Oklahoma, South Dakota, Texas, Utah, and Wyoming provided this
value is not contradicted by evidence in the record at the time the
State submits a demonstration.
    (iv) In addressing the requirements set forth in paragraph
(c)(3)(iv)(D) of this section regarding the not reasonably preventable
criterion, the State shall not be required to provide a case-specific
justification for a high wind dust event.
    (v) With respect to the not reasonably controllable criterion of
paragraph (c)(3)(iv)(D) of this section, dust controls on an
anthropogenic source shall be considered reasonable in any case in
which the controls render the anthropogenic source as resistant to high
winds as a natural undisturbed land area. The Administrator may
determine lesser controls reasonable on a case-by-case basis.
    (vi) For remote, large-scale, high-energy and/or sudden high wind
dust events, such as ``haboobs'' in the southwest, the Administrator
will generally consider a demonstration documenting the nature and
extent of the event to be sufficient with respect to the not reasonable
controllable criterion of paragraph (c)(3)(iv)(D) of this section.
    (6) Determinations with respect to event aggregation and multiple
national ambient air quality standards for the same pollutant. (i)
Where a State demonstrates to the Administrator's satisfaction that for
national ambient air quality standards with averaging or cumulative
periods longer than 24-hours the aggregate effect of events occurring
on different days has caused an exceedance or violation, the
Administrator shall determine such collective data to satisfy the
requirements in paragraph (c)(3)(iv)(B) of this section regarding the
clear causal relationship criterion and otherwise satisfies the
requirements of this section.

    (ii) The Administrator shall accept as part of a demonstration for
the clear causal relationship in paragraph (c)(3)(iv)(B) of this
section, a State's comparison of a 24-hour concentration of any
national ambient air quality standard pollutant to the level of a
national ambient air quality standard for the same pollutant with a
longer averaging period.
    (7) Determinations with respect to the not reasonably controllable
or preventable criterion. (i) The Administrator shall determine that an
event is not reasonably preventable if the State shows that reasonable
measures to prevent the event were applied at the time of the event.
    (ii) The Administrator shall determine that an event is not
reasonably controllable if the State shows that reasonable measures to
control the impact of the event on air quality were applied at the time
of the event.
    (iii) The Administrator shall assess the reasonableness of
available controls for anthropogenic sources based on information
available as of the date of the event.
    (iv) Except where a State is obligated to revise its state
implementation plan, the Administrator shall consider enforceable
control measures implemented in accordance with a state implementation
plan, approved by the EPA within 5 years of the date of a demonstration
submittal, that address the event-related pollutant and all sources
necessary to fulfill the requirements of the Clean Air Act for the
state implementation plan to be reasonable controls with respect to all
anthropogenic sources that have or may have contributed to event-
related emissions.
    (v) The Administrator shall not require a State to provide case-
specific justification to support the not reasonably controllable or
preventable criterion for emissions-generating activity that occurs
outside of the State's jurisdictional boundaries within which the
concentration at issue was monitored. In the case of a tribe with
treatment as a state status with respect to exceptional events
requirements, the tribe's jurisdictional boundaries for purposes of
requiring or directly implementing emission controls apply. In the case
of a federal land manager or other federal agency submitting a
demonstration under the requirements of this section, the
jurisdictional boundaries that apply are those of the State or the
tribe depending on which has jurisdiction over the area where the event
has occurred.
    (c) Schedules and procedures--(1) Public notification. (i) All
States and, where applicable, their political subdivisions must notify
the public promptly whenever an event occurs or is reasonably
anticipated to occur which may result in the exceedance of an
applicable air quality standard.
    (ii) [Reserved]
    (2) Initial notification of potential exceptional event. (i) A
State shall notify the Administrator of its intent to request exclusion
of one or more measured exceedances of an applicable national ambient
air quality standard as being due to an exceptional event by creating
an initial event description and flagging the associated data that have
been submitted to the AQS database and by engaging in the Initial
Notification of Potential Exceptional Event process as follows:
    (A) The State and the appropriate EPA regional office shall engage
in regular communications to identify those data that have been
potentially influenced by an exceptional event, to determine whether
the identified data may affect a regulatory determination and to
discuss whether the State should develop and submit an exceptional
events demonstration according to the requirements in this section;
    (B) For data that may affect an anticipated regulatory
determination or where circumstances otherwise compel the Administrator
to prioritize the resulting demonstration, the Administrator shall
respond to a State's Initial Notification of Potential Exceptional
Event with a due date for demonstration submittal that considers the
nature of the event and the anticipated timing of the associated
regulatory decision;
    (C) The Administrator may waive the Initial Notification of
Potential Exceptional Event process on a case-by-case basis.
    (ii) The data shall not be excluded from determinations with
respect to exceedances or violations of the national ambient air
quality standards unless and until, following the State's submittal of
its demonstration pursuant to paragraph (c)(3) of this section and the
Administrator's review, the Administrator notifies the State of its
concurrence by placing a concurrence flag in the appropriate field for
the data record in the AQS database.
    (iii) [Reserved]
    (iv) [Reserved]
    (v) [Reserved]
* * * * *
    (3) Submission of demonstrations. (i) Except as allowed under
paragraph (c)(2)(vi) of this section, a State that has flagged data as
being due to an exceptional event and is requesting exclusion of the
affected measurement data shall, after notice and opportunity for
public comment, submit a demonstration to justify data exclusion to the
Administrator according to the schedule established under paragraph
(c)(2)(i)(B).
    (ii) [Reserved]
    (iii) [Reserved]
    (iv) The demonstration to justify data exclusion must include:
    (A) A narrative conceptual model that describes the event(s)
causing the exceedance or violation and a discussion of how emissions
from the event(s) led to the exceedance or violation at the affected
monitor(s);
    (B) A demonstration that the event affected air quality in such a
way that there exists a clear causal relationship between the specific
event and the monitored exceedance or violation;
    (C) Analyses identified in Table 3 to Sec.  50.14 comparing the
claimed event-influenced concentration(s) to concentrations at the same
monitoring site at other times consistent with Table 3 to Sec.  50.14
to support the requirement at paragraph (c)(3)(iv)(B) of this section.
The Administrator shall not require a State to prove a specific
percentile point in the distribution of data;
    (D) A demonstration that the event was both not reasonably
controllable and not reasonably preventable; and
    (E) A demonstration that the event was a human activity that is
unlikely to recur at a particular location or was a natural event.
    (v) With the submission of the demonstration containing the
elements in paragraph (c)(3)(iv) of this section, the State must:
    (A) Document that the public comment process was followed and that
the comment period was open for a minimum of 30 days, which could be
concurrent with the Administrator's review of the associated
demonstration provided the State can meet all requirements in this
paragraph;
    (B) Submit the public comments it received along with its
demonstration to the Administrator; and
    (C) Address in the submission to the Administrator those comments
disputing or contradicting factual evidence provided in the
demonstration.
    (vi) Where the State has submitted a demonstration according to the
requirements of this section and the Administrator has reviewed such
demonstration and requested additional evidence to support one of the
elements in paragraph (c)(3)(iv) of this section, the State shall have
12 months from the date of the Administrator's request to submit such
evidence. At the

conclusion of this time, if the State has not submitted the requested
additional evidence, the Administrator will consider the demonstration
to be inactive and will not pursue additional review of the
demonstration. After a 12-month period of inactivity, if a State
desires to pursue the inactive demonstration, it must reinitiate its
request to exclude associated data by following the process beginning
with paragraph (c)(2)(i) of this section.

         Table 3 to Sec.   50.14. Evidence and Analyses for the Comparison to Historical Concentrations
----------------------------------------------------------------------------------------------------------------
    Historical concentration evidence      Types of analyses/supporting information      Required or optional?
----------------------------------------------------------------------------------------------------------------
1. Comparison of concentrations on the    Seasonal (appropriate if exceedances occur  Required seasonal and/or
 claimed event day with past historical    primarily in one season, but not in         annual analysis
 data.                                     others).                                    (depending on which is
                                           Use all available seasonal data     more appropriate).
                                           over the previous 5 years (or more, if
                                           available).
                                           Discuss the seasonal nature of
                                           pollution for the location being
                                           evaluated.
                                           Present monthly maximums of the
                                           NAAQS relevant metric (e.g., maximum
                                           daily 8-hour average ozone or 1-hr SO2)
                                           vs monthly or other averaged daily data
                                           as this masks high values.
                                          Annual (appropriate if exceedances are
                                           likely throughout the year).
                                           Use all available data over the
                                           previous 5 years (or more, if available).
                                          Seasonal and Annual Analyses..............
                                           Provide the data in the form
                                           relevant to the standard being considered
                                           for data exclusion.
                                           Label ``high'' data points as
                                           being associated with concurred
                                           exceptional events, suspected exceptional
                                           events, other unusual occurrences, or
                                           high pollution days due to normal
                                           emissions.
                                           Describe how emission control
                                           strategies have decreased pollutant
                                           concentrations over the 5-year window, if
                                           applicable.
                                           Include comparisons omitting
                                           known or suspected exceptional events
                                           points, if applicable.
2. Comparison of concentrations on the     Include neighboring days at the    Optional analysis.
 claimed event day with a narrower set     same location (e.g., a time series of two
 of similar days.                          to three weeks) and/or other days with
                                           similar meteorological conditions
                                           (possibly from other years) at the same
                                           or nearby locations with similar
                                           historical air quality along with a
                                           discussion of the meteorological
                                           conditions during the same timeframe. \a\
                                           Use this comparison to
                                           demonstrate that the event caused higher
                                           concentrations than would be expected for
                                           given meteorological and/or local
                                           emissions conditions.
3. Percentile rank of concentration when   Provide the percentile rank of     Required analysis when
 compared to annual data. \b\              the event-day concentration relative to     comparison is made on an
                                           all measurement days over the previous 5    annual basis (see item
                                           years to ensure statistical robustness      #1).
                                           and capture non-event variability over
                                           the appropriate seasons or number of
                                           years.\c\
                                           Use the daily statistic (e.g., 24-
                                           hour average, maximum daily 8-hour
                                           average, or maximum 1-hour) appropriate
                                           for the form of the standard being
                                           considered for data exclusion.
4. Percentile rank of concentration        Provide the percentile rank of     Required analysis when
 relative to seasonal data. \b\            the event-day concentration relative to     comparison is made on a
                                           all measurement days for the season (or     seasonal basis (see item
                                           appropriate alternative 3-month period)     #1).
                                           of the event over the previous 5 years.
                                           Use the same time horizon as used
                                           for the percentile rank calculated
                                           relative to annual data, if appropriate.
----------------------------------------------------------------------------------------------------------------
\a\ If an air agency compares the concentration on the claimed event day with days with similar meteorological
  conditions from other years, the agency should also verify and provide evidence that the area has not
  experienced significant changes in wind patterns, and that no significant sources in the area have had
  significant changes in their emissions of the pollutant of concern.
\b\ The EPA does not intend to identify a particular historical percentile rank point in the seasonal or annual
  historical data that plays a critical role in the analysis or conclusion regarding the clear causal
  relationship.
\c\ Section 8.4.2.e of appendix W (proposed revisions at 80 FR 45374, July 29, 2015) recommends using 5 years of
  adequately representative meteorology data from the National Weather Service to ensure that worst-case
  meteorological conditions are represented. Similarly, for exceptional events purposes, the EPA believes that 5
  years of ambient air data, whether seasonal or annual, better represent the range of ``normal'' air quality
  than do shorter periods.

[FR Doc. 2015-29350 Filed 11-19-15; 8:45 am]
BILLING CODE 6560-50-P


[Federal Register Volume 78, Number 194 (Monday, October 7, 2013)]
[Notices]
[Pages 61942-61943]
[FR Doc No: 2013-24366]

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

DEPARTMENT OF ENERGY

Federal Energy Regulatory Commission

Combined Notice of Filings 1

    Take notice that the Commission received the following electric
corporate filings:

    Docket Numbers: EC13-155-000.
    Applicants: Consolidated Edison Company of New York,.
    Description: Section 203 Application of Consolidated Edison Company
of New York, Inc.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5136.
    Comments Due: 5 p.m. ET 10/17/13.

    Take notice that the Commission received the following exempt
wholesale generator filings:

    Docket Numbers: EG13-63-000.
    Applicants: Mountain Wind Power, LLC.
    Description: Notice Of Self-Certification Of Exempt Wholesale
Generator Status Of Mountain Wind Power, LLC.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5096.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: EG13-64-000.
    Applicants: Mountain Wind Power, LLC.
    Description: Notice Of Self-Certification Of Exempt Wholesale
Generator Status Of Mountain Wind Power II, LLC.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5098.
    Comments Due: 5 p.m. ET 10/17/13.

    Take notice that the Commission received the following electric
rate filings:
    Docket Numbers: ER10-1847-004; ER10-1856-004; ER10-1890-004; ER11-
2160-004; ER10-1962-004; ER11-4677-005; ER12-2444-004; ER10-1989-004;
ER10-1992-004; ER11-4678-005; ER12-631-005; ER10-1971-012.
    Applicants: Diablo Winds, LLC, FPL Energy Cabazon Wind, LLC, FPL
Energy Green Power Wind, LLC, FPL Energy Montezuma Wind, LLC, High
Winds, LLC, NextEra Energy Montezuma II Wind, LLC, North Sky River
Energy, LLC, Sky River LLC, Victory Garden Phase IV, LLC, Vasco Winds,
LLC, Windpower Partners 1993, LLC, NextEra Energy Power Marketing, LLC.
    Description: Notification of Non-Material Change in Status of the
NextEra Resources Entities.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5139.
    Comments Due: 5 p.m. ET 10/17/1.

    Docket Numbers: ER12-2643-003.
    Applicants: California Independent System Operator Corporation.
    Description: 2013-09-26--DGD to be effective 11/18/2012.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5091.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: ER13-1963-001.
    Applicants: Midcontinent Independent System Operator, Inc.
    Description: 09-26-2013 Sch 43C Ameren Deficiency Response to be
effective 1/1/2013.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5069.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: ER13-2087-001.
    Applicants: Arizona Public Service Company.
    Description: Revisions to Rate Schedule 268--Compliance Filing to
be effective 10/1/2013.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5037.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: ER13-2456-000.
    Applicants: Arizona Public Service Company.
    Description: Rate Schedule No. 249 Amendment 1 Round Valley
Substation to be effective 10/1/2013.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5038.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: ER13-2457-000.
    Applicants: Arizona Public Service Company.
    Description: Service Agreement No. 219, Amendment 1 Saddlebrooke
Ranch Substation to be effective 10/1/2013.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5039.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: ER13-2458-000.
    Applicants: Tuscola Wind II, LLC.
    Description: Tuscola Wind II, LLC Application for Market-Based
Rates to be effective 11/10/2013.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5062.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: ER13-2459-000.
    Applicants: Elizabethtown Energy, LLC.
    Description: Seller Category Revision to Market-Based Rate Tariff &
Request for Notice Waiver to be effective 9/27/2013.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5063.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: ER13-2460-000.
    Applicants: Lumberton Energy, LLC.
    Description: Seller Category Revision to Market-Based Rate Tariff &
Request for Notice Waiver to be effective 9/27/2013.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5067.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: ER13-2461-000.
    Applicants: Pheasant Run Wind, LLC.
    Description: Pheasant Run Wind, LLC Application for Market-Based
Rates to be effective 11/25/2013.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5101.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: ER13-2462-000.
    Applicants: Pheasant Run Wind II, LLC.
    Description: Pheasant Run Wind II, LLC Application for Market-Based
Rates to be effective 2/1/2014.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5103.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: ER13-2465-000.
    Applicants: Pepco Energy Services, Inc.
    Description: Application of Pepco Energy Services, LLC to allow PJM
Interconnection, L.L.C. to terminate

payments for Reactive Supply and Voltage Control from Generation
Resources in connection with retired plants.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5134.
    Comments Due: 5 p.m. ET 10/17/13.

    Docket Numbers: ER13-2466-000.
    Applicants: Unitil Energy Systems, Inc.
    Description: Notice of Termination of Unitil Energy Systems, Inc.
Rate Schedule No. 2 with New Hampshire Hydro Associates.
    Filed Date: 9/26/13.
    Accession Number: 20130926-5135.
    Comments Due: 5 p.m. ET 10/17/13.

    The filings are accessible in the Commission's eLibrary system by
clicking on the links or querying the docket number.
    Any person desiring to intervene or protest in any of the above
proceedings must file in accordance with Rules 211 and 214 of the
Commission's Regulations (18 CFR 385.211 and 385.214) on or before 5:00
p.m. Eastern time on the specified comment date. Protests may be
considered, but intervention is necessary to become a party to the
proceeding.
    eFiling is encouraged. More detailed information relating to filing
requirements, interventions, protests, service, and qualifying
facilities filings can be found at: http://www.ferc.gov/docs-filing/efiling/filing-req.pdf. For other information, call<PHONE_NUMBER>
(toll free). For TTY, call<PHONE_NUMBER>.

    Dated: September 27, 2013.
Nathaniel J. Davis, Sr.,
Deputy Secretary.
[FR Doc. 2013-24366 Filed 10-4-13; 8:45 am]
BILLING CODE 6717-01-P