Exceptional Events Rule Revisio

Notice of Proposed Rulemakin

and 

Draft Wildfire/Ozone Guidanc

Notice of Availability

US EPA

Office of Air Quality Planning and Standards 

November 2015

Disclaimer: Positions and views expressed here represent proposed rule content and draft E
Overview

• Key Points

• Background on Exceptional Events Rule and Guidanc

• Exceptional Events Schedule in 2015 Ozone NAAQS

• Anticipated Schedule for Rule and Guidance• Exceptional Events Rule Revisions• Wildfire/Ozone Exceptional Events Implementation

Guidance

• Communication and Outreach• Available Resources• Clarifying Questions
Key Points

• EPA initiated the Exceptional Events Rule revisions and guidance de

process to address certain substantive issues raised by state, local a

regulators and other stakeholders since promulgation of the rule an

increase the administrative efficiency of the Exceptional Events Rul

and process.

• The rule revisions and guidance are intended to make the demonst

manageable for the air agency seeking to exclude data and for the 

reviewing and acting on these demonstrations.

• EPA initiated the rulemaking effort to address concerns and reques

additional flexibility raised by stakeholders that could not be achiev

the Interim Exceptional Events Implementation Guidance issued in 

• The exceptional events improvements efforts over the past several 

been collaborative involving multiple public webinars, listening sess

meeting presentations and best practices discussions.

• The Exceptional Events Rule revisions and related guidance are key 

in implementing the 2015 revised Ozone NAAQS.
Background

• Origin of the Exceptional Events Rule

• Promulgated on March 22, 2007 (72 FR 13560)

• Required by statute (Section 319 of the Clean Air Act)

• Replaced previous EPA policies/procedures

• Applies to all criteria pollutants and NAAQS and includes genera

for identifying data and submitting demonstrations

• Elements of the Exceptional Events Rule

• Establishes procedures and criteria for identifying, evaluating,

interpreting, and using air quality monitoring data affected by ex

events

• Provides a mechanism by which air quality data can be excluded 

regulatory decisions and actions

• Affects design value calculations, NAAQS designation decisions,

attainment determinations, and State / Tribal Implementation P

development
Background

• Criteria To Be an Exceptional Event (2007 Rule)

• The event affects air quality

• The event is not reasonably controllable or preventable

• The event is caused by human activity that is unlikely to recur at 

location or is a natural event

• There is a clear causal relationship between the event and the m

concentration

• The event is associated with a measured concentration in excess 

normal historical fluctuations

• There would have been no exceedance or violation but for the e

• Examples of Exceptional Events

• High Wind Dust Events

• Wildfire Events

• Volcanic and Seismic Activities
Background

• Exceptional Events Rule Current Process

• Air agency identifies potential event‐related exceedance

• Air agency flags data in Air Quality System (AQS) and provides EPA w

event description

• Air agency prepares demonstration package and provides public not

opportunity to comment

• Air agency submits demonstration package to support data exclusion

• EPA reviews submittal and either approves or disapproves the excep

event claim

• If EPA agrees that event is “exceptional,” then data are excluded

• If EPA does not agree with air agency claim, then data remain and are u

regulatory determinations

• Implementation has been Challenging

• Exceptional events are unique and varied

• Difficult to provide guidance that is both concrete and generally app

• Difficult to pre‐determine how much evidence / technical analysis fo

demonstrations is enough

• Final rule text and preamble left room for interpretation
Background

• March 2007 – Exceptional Events Rule promulgated• May 2013 ‐ EPA finalized interim exceptional events implemen

guidance

• Memorandum to Regional Air Division Directors with 2 attachme

• Attachment 1 ‐ Frequently Asked Questions document

• Attachment 2 ‐ High Winds Guidance document

• May 2013 – EPA announced intent to revise the Exceptional Ev

and develop wildfire/ozone implementation guidance

• August thru November 2013 – Stakeholder outreach and listen

sessions related to rule revisions

• November 2014 – Ozone NAAQS proposal containing flagging 

demonstration submission schedule for data influenced by exc

events

• October 2015 – Final Ozone NAAQS containing exceptional eve

submission schedule (promulgated as proposed)
Exceptional Events Schedule in 2015 Ozo

NAAQS

• Developed to ensure that EPA has adequate time to assess any excep

events demonstrations that would substantively affect designations u

2015 revised Ozone NAAQS (e.g., nonattainment vs. attainment, Mar

Moderate). Relevant monitoring data years:

• 2014‐2016 for ozone designations promulgated in October 2017 under the 

designation schedule

• 2017 data ‐ only if designations are completed under a 3‐year schedule

• Schedule follows past practice and splits the available time during the

designations process between the states and EPA.

• Schedule establishes demonstration submission deadlines as follows:

• October 1, 2016 (for 2013 ‐ 2015 data)

• May 31, 2017 (for 2016 data)

• Demonstration submission rule language in the 2015 Ozone NAAQS s

generic “delta schedule” that could be applied to any future NAAQS r

• The proposed Exceptional Events Rule revisions retain the same “delt

schedule” that we promulgated in the 2015 Ozone NAAQS.
Anticipated Schedule for Rule and Guidan

• Exceptional Events Rule revisions and guidance developm

• November 10, 2015 – sign Notice of Proposed Rulemaking f

revisions and Notice of Availability for draft guidance

• November 2015 – publication in Federal Register

• December 8, 2015 – public hearing in Phoenix, Arizona (10a

Arizona Department of Environmental Quality office)

• January 19, 2016 – close of comment period

• August 2016 – sign final rule and issue final guidance docum

• Relationship to other actions

• Schedule allows air agencies approximately 2 months to co

final rule revisions and final guidance prior to submitting th

designation recommendations for the 2015 Ozone NAAQS (

10/1/2016, using 2013‐2015 data).
Proposed Exceptional Events Rule

Revisions 

• Clarify the types of determinations and actions to which the a

statutory authority in CAA section 319(b) applies

• Designations• Classifications• Attainment determinations

• Attainment date extensions

• Findings of SIP inadequacy leading to SIP call

• Return to the core statutory elements and implicit concepts of 

section 319(b)

• The event affected air quality in such a way that there exists a cle

relationship between the specific event and the monitored excee

violation (as supported by a comparison of the of the claimed eve

influenced concentration(s) to concentrations at the same monito

other times)

• The event was not reasonably controllable or preventable

• The event was a human activity that is unlikely to recur at a partic

location or was a natural event
Proposed Exceptional Events Rule

Revisions 

• Clarify “not reasonably controllable or preventable” criteria

• Rely on attainment/maintenance SIPs approved within 5 years of demonstration submittal

• Indicate that air agencies generally have no obligation to specifica

controls for emissions originating outside their jurisdictional (i.e., state/tribal/international) border(s)

• “Controllable” and “preventable” are separate tests

• Clarify high wind elements currently addressed in guidance

• Include provisions for the high wind threshold

• Include provisions for “extreme” events

• Codify requirements for the content and organization of excep

events submittals

• Make initial notification by the state to the EPA of a potential exce

event a required (but waivable) preliminary step before submittin

demonstration (based on best practices)

• Include narrative conceptual model• Address core statutory elements• Include documentation that public comment process was conduc

• Remove “general schedule” deadlines for data flagging and demonstration submittal
Proposed Exceptional Events Rule

Revisions 

• New fire‐related rule language and preamble text

• Clarify that all wildfires on wildland are natural events

• Clarify that prescribed fire is a human‐caused event eligible for tr

an exceptional event and propose a streamlined path to show ho

agencies can satisfy rule criteria

• Rely on land/resource management plans (for frequency of recurrenc

“not reasonably preventable”)

• Identify recommended components of Smoke Management Program

Smoke Management Practices

• Define fire‐related terms in regulatory language

• Other provisions

• Address who may submit a demonstration

• Event aggregation

• Mitigation
Draft Wildfire/Ozone Exceptional Events

Implementation Guidance

• Full document name: Draft Guidance on the Preparation of

Exceptional Events Demonstrations for Wildfire Events that 

Influence Ozone Concentrations

• What does the draft guidance do?

• Incorporates and applies the proposed rule revisions to wildfir

events

• Provides example analyses, conclusion statements, and techni

that air agencies can use to provide evidence that the wildfire 

influenced the monitored ozone concentration

• Invites comment on the appropriateness of either expanding t

wildfire/ozone guidance, or developing a separate guidance d

to specifically address demonstration components for prescrib
Draft Wildfire/Ozone Exceptional Events

Implementation Guidance

• What does the draft guidance do?

• Identifies fire and monitor‐based characteristics that would 

a streamlined demonstration package using a three‐tiered 

• Tier 1 demonstrations

• Simplest and least resource intensive

• Apply when fire events cause clear O3 impacts in areas or during t

that typically experience lower O3 concentrations

• Use time series plot and evidence of transport to the monitor

• Tier 2 demonstrations

• Apply when the impacts of the fire on O3 levels are less clear and 

require more evidence than Tier 1 demonstrations

• Use Q/D (emissions/distance) screening criterion, threshold‐base

concentrations and evidence of transport to and influence at the 

• Tier 3 demonstrations

• Apply when the relationship between the subject fires and influe

concentrations is more complicated

• Build upon tiers 1 and 2

• Appropriate tier to be determined by affected air agency and reviewing E

office during proposed “Initial Notification” process
Proposed Exceptional Events Rule Revisio

and Draft Guidance – Requests for Comme

• Proposed Exceptional Events Rule Revisions

• Incorporating elements of guidance in rule revisions

• Clarifications to the scope of Administrator determinations included wit

Exceptional Events Rule

• Components and approaches associated with “not reasonably controlla

“not reasonably preventable”

• Proposed approach to defining recurrence at a particular location

• Approaches that could effectively communicate expectations regarding reasonable controls

• Characterizing “extreme” events

• Incorporating smoke management program elements in rule text versus 

• Appropriateness of Federal Land Managers and other federal agencies s

demonstrations directly to EPA

• Proposed changes to the Air Quality System for data flagging

• Approaches for mitigation, including whether changes are needed, plan

components and implementation

• Draft Wildfire/Ozone Guidance

• Approach for tiering• Key factors

• Appropriateness of either expanding the wildfire/ozone guidance or dev

separate guidance document, to specifically address demonstration com

for prescribed fires 
Communication and Outreach

• Public outreach webinar following proposal

• Content of the proposed rule revisions

• Content of draft guidance

• Public hearing

• December 8, 2015 from 10am – 6pm• In Phoenix, Arizona at Arizona Department of Environ

Quality offices

• Details and registration information provided in Feder

Register and on Exceptional Events website

• Implementation workshop(s) for states, tribes, and o

affected stakeholders following rule promulgation a

release of final guidance

• Continued development of exceptional events tools 

website, templates)

• Revisions to existing Interim Exceptional Events Implementation Guidance following promulgation
Available Resources

• Docket for the rule revisions: EPA‐HQ‐OAR‐2013‐0576 at

http://www.regulations.gov

• Docket for the draft wildfire guidance: EPA‐HQ‐OAR‐2015‐0229 at

http://www.regulations.gov

• Exceptional Events Website at http://www2.epa.gov/air‐quality‐

analysis/treatment‐data‐influenced‐exceptional‐events

• EPA Regional Office staff and/or EPA Office of Air Quality Planning 

Standards staff
Clarifying Questions