150 SOUTH NINTH STREET 

EL CENTRO, CA 92243-2850 

TELEPHONE: (442) 265-1800 

FAX: (442) 265-1799 

AIR POLL 

January 19, 2016 

U.S. Environmental Protection Agency 

EPA Docket Center 

Attention: Docket ID No. EPA-HQ-OAR-2013-0572 

Mail Code 2821T 

1200 Pennsylvania Avenue, NW 

Washington, DC 20460 

DISTRICT 

RE: Imperial County APCD Comments on EPA's proposed revisions to the 2007 Exceptional 

Events Rule 

To Whom It May Concern: 

Pursuant to the solicitation for public comment published in the Federal Register by U.S. Environmental 

Protection Agency (EPA) on November 20, 2015 (80 FR 72839), the Imperial County Air Pollution Control 

District (ICAPCD) is pleased to provide the following comments on EPA's proposed revisions to the 2007 

Exceptional Events Rule (EER). 

First and foremost, ICAPCD would like to express our recognition and appreciation to EPA for the effort 

made in reviewing, preparing, and working with air agencies in proposing these changes to the 2007 

EER. As a small air agency, it is imperative that we receive consistent and reliable assistance from EPA 

on such a scientific and technical process that is getting concurrence on demonstrations of Exceptional 

Events that may have huge consequences in planning efforts and attainment status. 

Due to the applicability of this rule to current and future Exceptional Events in Imperial County, the 

ICAPCD has continued to be engaged in the process for the review and guidance of the EER. Our last 

comment letter dated August 30, 2012 outlined our concerns with the Draft Exceptional Events 

Guidance and its related documents. To recap briefly, the concerns we shared at that time dealt with 

our belief that changes needed to come in the form of rule revisions and not guidance, disagreements 

with EPA's high wind event, "reasonable control", and "but for" interpretations, not to mention the 

extreme rigor in analyses that seemed open ended and the resources required for event submittals. 

AN EQUAL OPPORTUNITY I AFFIRMATIVE ACTION EMPLOYER 

1 
With this current proposed rulemaking, EPA has addressed one of our main concerns which is we 

believe that revisions needed to occur as part of an official rule making process. We understand that 

this is, and has been, a very lengthy process but we feel it was necessary in order to remove much of the 

uncertainty and clarity issues that have plagued the process in the past. 

While we agree and appreciate the helpful proposed general changes with respect to clarifying what 

constitutes and exceptional event which include: 

• Revising the definition of exceptional event by including the concept of considering the 

combined effects.of an event and resulting emissions. 

• Removing the "but for" element 

• Moving the "clear causal relationship" element into list of criteria that must be met 

• Subsuming the "affects air quality" element into the "clear causal relationship" element. 

• Removing the term "historical fluctuations" and replacing it with text referring to a 

comparison to historical concentrations, identifying types of analyses that are necessary 

in a demonstration. 

However, we feel there is still a need for further revisions throughout the draft rule which are explained 

below. 

As a general comment, we would like to see the proposed changes in strikeout/underline format (same 

as required of air agencies to provide EPA when adopting new or revised rules) to minimize time 

comparing different versions of the rule and to facilitate more focused review. 

Scope and Applicability 

EPA is proposing to limit exceptional event requests to a specific set of regulatory actions (i.e., 

initial area designations, classifications, attainment determinations, determinations regarding requests 

for attainment date extensions, and findings of SIP inadequacy leading to a SIP call). However, there 

may be other compelling reasons why states and local air agencies would want EPA action on an 

exceptional event demonstration, including exceedances that may contribute to a violating design value 

in a future year; exceedances that may impact modeling or statistical analyses; exceptional event 

demonstrations that use historical data comparisons; and to address public perception of air quality in a 

region. ICAPCD urges EPA to not limit demonstrations to just the five types of regulatory actions in the 

proposed rule, but to also include an option for the region and state to decide on a case-by-case basis 

that data from an event outside the listed regulatory actions may be considered for exclusion as an 

exceptional event. 

We appreciate that EPA is proposing to issue an alternative to the rule itself for excluding 

exceptional events (Draft Guidance for Excluding Some Ambient Pollutant Concentration Data from 

Certain Calculation and Analysis for Purposes Other than Retrospective Determination of Attainment of 

the NAAQS), suggesting that this will address exceptional events that do not fall into the list of five 

proposed in the Rule. However, because this guidance will not be available before the Exceptional Event 

Rule revisions are final, states cannot rely on it to address the above concerns. While the forthcoming 

2 
guidance may provide other options, without knowing what will be in this document, and for states that 

must rely on requirements within a rule, the Rule should contain the option to consider other events for 

exclusion on a case-by-case basis. 

Not Reasonably Preventable and Controllable 

As a condition for approval of an exceptional event request, states are required to demonstrate, 

to EPA's satisfaction, that any control measures that could "reasonably" have been in place at the time 

of the event must have been in place, including escalating control measures in areas subject to recurring 

dust events and wildfire events. ICAPCD supports EPA's proposal to consider relevant control measures 

included in non-attainment and maintenance SIPs approved within five years of the event sufficient to 

meet this criterion and appreciate EPA's recognition of the role SI P's play in establishing reasonable 

control measures. Additionally, to clarify the proposed rule language at S0.14(b)(7)(iv): 11 

••• approved by 

the EPA within 5 years of the date of a demonstration submittal . .. 1

11 we urge EPA revise the language to 

say" ... approved by the EPA within 5 years of the date of an event at issue ... " The revision aligns with 

the language in the preamble at 72861, center column, first full paragraph. It makes sense that the 

approval date of the SIP should fall within five years of the event and not a demonstration submittal, 

which may be submitted an unspecified number of years after the event. 

We also agree that the implementation of measures that would materially provide public health 

protections against unhealthy levels of air pollution make sense, such as those measures outlined in 

Section VI of the preamble, states and local air agencies should not be required to guess what additional 

measures EPA would find acceptable to qualify as "reasonable" under the exceptional events rule. We 

therefore reiterate our previous comments that if EPA believes that any state SIP is deficient, it is EPA's 

responsibility to clearly identify the deficiency and the measures they believe are necessary to provide 

for attainment and maintenance of the relevant air quality standard. Finally, while we agree that in 

areas with recurring events, a periodic review of controls is appropriate, an increasing level of control 

may not necessarily be either feasible or effective. 

Mitigation 

ICAPCD supports the requirements of 40 CFR 51.930 to take appropriate and reasonable actions 

to protect public health by providing prompt public notification, public education concerning actions 

individuals may take to reduce exposure, and implementation of appropriate measures to protect public 

health. In the preamble to the 2007 Exceptional Events Rule, EPA stated that states should take 

reasonable and appropriate measures to protect public health, and that states should determine what 

measures constitute those that are reasonable and appropriate. Based on experience to date in 

implementing the Exceptional Events Rule, ICAPCD believes this approach continues to be the most 

effective method for addressing public notification and mitigation requirements. We note that many 

states and local air agencies have existing documents or mechanisms in place that address these 

requirements. ICAPCD therefore continues to support EPA's current approach that provides flexibility 

3 
and deference to states in determining the most appropriate mitigation and public notification efforts 

and mechanisms. 

Submittal of Exceptional Event Requests by Federal Land Managers 

ICAPCD has concerns about EPA allowing federal agencies (land managers) to flag data and 

submit demonstrations independent of the state and local air agencies. While we welcome 

collaboration from federal agencies in preparing demonstrations for exceptional events where 

regulatory-grade federal monitors have measured exceedances or the event originated on federal land, 

we do not believe it is appropriate to grant authority for these decisions to an agency other than an air 

quality agency, because other agencies have different functions and priorities. Although the proposal 

provides that the federal agency should proceed with developing the demonstration only after 

"discussing" the event with states, granting land managers the authority to submit demonstrations is 

inappropriate. Instead, while the decision to develop and the development of a demonstration may be 

a joint one, between the air agency, land manager and EPA, the responsibility for air quality in a state, 

including exceptional event requests, rests with the state agency. Therefore, ICAPCD does not support 

the section of the proposal that grants flagging and demonstration submittal authority to federal land 

managers. 

Timing 

ICAPCD believes that EPA should make a timely determination on all submittals that meet the 

criteria in the proposed Exceptional Events Rule, or that the state and EPA have decided on a case-bycase basis to consider. This was EPA's intent when it drafted the, Interim Guidance on the Preparation of 

Demonstrations in Support of Requests to Exclude Ambient Air Quality Data Affected by High Winds 

Under the Exceptional Events Rule in May, 2013. On page 33 of that document, EPA proposed to conduct 

a complete initial review and send a letter to the state, "outlining preliminary assessment of 

completeness of package/need for additional Information" within 120 days of receipt of the 

demonstration. EPA further proposed that states would then have 60 days to respond. We request that 

EPA include, within the proposed Exceptional Events Rule, a similar timeframe under which EPA must 

respond to state submittals with a completeness letter and note any additional information that is 

needed. We also believe that EPA should include, within this proposed rule, a 12 month deadline from 

the date the submittal was received in which EPA must concur on a submittal or explain why they 

cannot. 

Dispute Resolution Process 

As noted in our previous comments, ICAPCD continues to believe that the Exceptional Events 

Rule should contain an administrative dispute resolution process to resolve disagreements over 

concurrence or approvals before a significant regulatory action is taken. We agree that establishing 

early and regular communication with EPA regional office staff is a positive step. As part of this 

communication process, we support EPA's proposal regarding requirements for initial notification of 

exceptional event requests states and air agencies expect to pursue. This initial notification will help 

4 
establish a dialog between EPA, states and air agencies regarding expectations for subsequent 

documentation that will support development of approvable demonstrations. 

However, situations may still occur where states and air agencies will disagree with an EPA 

regional office action to disapprove a demonstration package. We therefore reiterate our 

recommendation for EPA to develop an administrative dispute resolution process. This process should 

ensure that states and air agencies have the ability to present their concerns to EPA Headquarters staff 

directly, or could alternatively involve a third party with technical expertise to provide for an 

independent review of the documentation prepared by a state and air agency as well as the EPA 

regional office assessment. 

In closing, the ICAPCD appreciates EPAs efforts to date and we also appreciate the opportunity to share 

our comments and concerns with EPA and do look forward to our continued collaboration on the 

proposed Exceptional Events Rule. We believe this rule is absolutely necessary and a vital tool for the 

ICAPCD and other air agencies to use and will allow us to focus on effective air quality efforts that 

benefit public health. 

Brad Poiriez 

Air Pollution Control Officer 

cc: Imperial County Air Pollution Control Board of Directors 

California Air Resources Board 

U.S. EPA Region IX 

California Air Pollution Control Officers Association (CAPCOA) 

Western States Air Resource Council (WESTAR) 

National Association of Clean Air Agencies (NACAA) 

5