EPA Region 10

Review of Exceptional Event Request

2012 Klamath Falls, Oregon

24-hour PM2.5 NAAQS

Dates Analyzed: August 25, 28 and 31, 2012

Background

On March 22, 2007, the EPA adopted a final rule, Treatment of Data Influenced by Exceptional Events

(Exceptional Events Rule at 72 FR 13560), to govern the review and handling of certain air quality

monitoring data for which the normal planning and regulatory processes are not appropriate. Under the

Exceptional Events Rule, the EPA may exclude data from use in determinations of National Ambient

Air Quality Standard exceedances and violations if a state demonstrates that an "exceptional event"

caused the exceedances. Before the EPA can exclude data from these regulatory determinations, the

state must flag the data in the EPA's Air Quality System database and, after notice and opportunity for

public comment, submit a demonstration to justify the exclusion. After considering the weight of

evidence provided in the demonstration, the EPA decides whether or not to concur with each flag.

ODEQ's Request

The Oregon Department of Environmental Quality requested concurrence on flagged 24-hour PM2 .5 data

on multiple days for the Peterson School monitor (Klamath Falls, Klamath County, Oregon, AQS site

41-035-0004 POCI); herein this will be referred to as "the monitor." The recorded 24-hour PM2.5 levels

for the monitor ranged from 28.1 μg/m3 to 43.2 μg/m3 for the data values for which the ODEQ is

requesting the EPA's concurrence as exceptional events. Table 1 lists all of the values at the monitor for

which the ODEQ has requested EPA concurrence.

Table 1. Dates and Values Flagged by ODEQ

Klamath Falls Monitored Values

Date PM2 .5 concentration (μg/m3 ) -

AQS site 41-035-0004 POCI.

8/25/2012 28.1

8/28/2012 43.2

8/31/2012 34.1

The submitted days were deemed regulatorily significant as they contributed to the 2012-2014 design

value that led to violation of the PM2.5 NAAQS. Documentation provided by the ODEQ demonstrates

that there were multiple wildfires occurring in Oregon and California in late summer 2012, notably the

Bagley Complex fire in California.

The ODEQ flagged the monitored values as wildfire exceptional events before the statutory deadline of

July 1, 2013. The agency made the documentation available for public comment for 30 days starting on

October 1, 2014 and received no comments. The ODEQ submitted the exceptional event demonstration

package to the EPA Region 10 on November 12, 2014 for three dates at the site. The ODEQ is

requesting concurrence from the EPA on all of these days.

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The EPA's Exceptional Event Evaluation

The EPA evaluated whether the documentation provided by the ODEQ for the flagged values at the

monitor demonstrates that the requirements of the Exceptional Events Rule were met. The EPA has

determined that all values would be used in a regulatory determination and the EPA has therefore

evaluated all of the days and values listed in Table 2 with respect to the Exceptional Event Rule

requirements.

The matrix below summarizes the requirements of the Exceptional Events Rule and describes how the

ODEQ met each requirement. All references to page numbers, tables, and figures relate to the ODEQ's

November 12, 2014 submittal.

Procedural Requirements: EPA's Evaluation of Flagged Exceedances:

• The data are flagged

and include an initial

event description in

the EPA's AQS

database. 40 CFR

50.14(c)(2)(i) and (iii)

The ODEQ flagged and described the summer 2012 elevated

PM2.5 values as wildfire exceptional events in the EPA's AQS

database prior to the July 1, 2013 deadline.

• The public had an

opportunity to review

and comment on the

demonstration

justifying the data

exclusion. 40 CFR

50.14(c)(3)(i) and (v)

The ODEQ provided a 30-day public comment period on the

documentation for the multi-day claimed exceptional event.

The public comment period occurred between October 1, 2014

and November 1, 2014 for the demonstration. The ODEQ

received no comments during the public comment period.

• The demonstration

justifying the data

exclusion was

submitted timely to

the EPA. 40 CFR

50.14(c)(3)(i)

The EPA received demonstration documentation from the

ODEQ on November 12, 2014 before the deadline of not later

than three years following the end of the calendar quarter in

which the flagged concentration was recorded (in this case,

September 30, 2015).

Technical Criteria:

• The event satisfies

the criteria in 40

CFR 50.10) (i.e.,

affects air quality, is

not reasonably

controllable or

preventable, is an

event caused by

human activity that

is unlikely to recur at

Conceptual Model

The ODEQ developed a conceptual model that shows how

wildfires in Oregon and California affected air quality in the

Klamath Falls area during the summer of 2012. In 2012, more

than 1.2 million acres in Oregon burned as a result of wildfires

(Table 3). Typically, Oregon and the surrounding region have

less than 2 million acres that burn, but in 2012 over 7 million

acres burned. This was the largest acreage in the past 12 years

(p 11, 12). The Bagley Complex wildfire ignited in midAugust 2012 70 miles to the SSW of Klamath Falls and

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a particular location

or is a natural event,

and is determined by

EPA to be an

exceptional event).

40 CFR

50.14(c)(3)(iii)(A)

generated a smoke plume that directly impacted the monitor.

Additional nearby wildfires also generated emissions (Figure

14).

Affected Air Quality

As evidence that the event affected air quality, the ODEQ

documented that the event exceeded historical fluctuations and

that there was a clear causal relationship between the event and

the exceedances at the monitor. As discussed above, in 2012,

wildfires burned over 1.2 million acres in Oregon (Table 3).

As mentioned in the conceptual model section, multiple

wildfires burned in the summer of 2012 in areas impacting the

monitor. As shown on Table 1, elevated values ofPM2.5

occurred at the end of August 2012.

The historical fluctuations criterion is discussed in further

detail later in this analysis. The clear causal relationship

criterion (also discussed later in further detail) also supports

the conclusion that the event affected air quality by describing

conceptually how the emissions generated by the wildfires

reached the monitor, and by analyzing each affected day using

HYSPLIT air mass back trajectories, hourly PM2.5 levels,

observed meteorological data, MODIS imagery, and/or text.

The Appendices provide supporting information in the form of

daily data analyses, newspaper articles and distributed ODEQ

air quality alerts.

Natural Event and not Reasonably Controllable or

Preventable

In 2012, wildfires burned more than 1.2 million acres in

Oregon. Weather conditions in Oregon during July and August

are typically hot and dry (Figures 2, 3, 6). In August 2012, the

mean temperature in Oregon was elevated compared to prior

years (Figure 12). The combination of hot and dry conditions

made the area more susceptible to wildfires (Figure 12).

While there were multiple wildfires in Oregon and surrounding

states in the summer of 2012, Klamath Falls was primarily

affected by the Bagley Complex fire 70 miles SSW in

California. This fire was ignited by lightning on August 18,

2012 that burned 47,011 acres and cost an estimated $1.4

million to control. It was controlled approximately 1 month

later on September 15, 2012. Table 10 identifies that 1,655

people were part of the response effort. It was managed using

the National Park Service management strategy (page 19) and

was physically controlled by the United States Forest Service

under full suppression management (page 20). Based on

historical records, the 1.2 million acres burned from wildfires

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in Oregon was over 4 times the average annual amount of

wildfire burned acres from the prior 10 years (page 19).

The ODEQ discussed that, based on interviews with multiple

state and local officials, there were no unusual anthropogenic

sources of emissions during this period. Typically,

anthropogenic emissions are low in August. No prescribed

burning or slash burning occurs during July and August

because conditions are highly susceptible to loss of control of

fires. (Table 2 in the executive summary, page 14, page 21,

Section 7.3 on page 49).

Based on the submitted information, the EPA concludes that

the wildfires that occurred in and around southwest Oregon in

late August 2012 were natural events that affected air quality

at the monitor and that they were not reasonably controllable

or preventable due to their size despite the significant

resources committed to suppression of these fires by the land

management agencies.

• There is a clear

causal relationship

between the

exceedance and the

claimed exceptional

event. 40 CFR

50.14(c)(3)(iii)(B)

Overview

The ODEQ established the clear causal relationship by

describing how the elevated emissions in Klamath Falls came

primarily from the Bagley Complex fire in California. The

ODEQ also identified multiple other fires in Oregon during

August 2012.

The ODEQ documented the direct connection between the

fires and the monitor using MODIS satellite images, HYSPLIT

back trajectories, and wind/temperature data.

MODIS satellite imagery on pages 24-26, Figure 23-25, show

the smoke plume from the Bagley Complex fire on August 25,

28, and 31 and how Klamath Falls is at times directly within

the plume. It also depicts three other fires in the area: the Fort

Complex fire, North Pass fire, and Chips Wildfire. The

imagery indicates that the plume from the North Pass fire also

may have directly contributed to the elevated monitor values,

with emissions from the other fires potentially contributing to

elevated PM25 levels at the monitor.

Figure 26 shows a multi-input graph including wind speed,

emissions levels, and wind directions. It supports the visual

evidence of the MODIS images by showing that the winds

were coming from the south (from the direction of the Bagley

Complex fire) during times of elevated emissions levels at the

monitor and at speeds sufficient to transport the emissions

from the fires to the monitor. HYSPLIT modeling further

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supports this by showing the trajectory of the emissions plume

intersecting with Klamath Falls on the days of higher recorded

emissions during the event (Figures 30, 31). Wind roses in

Figures 34-36 also support that winds were coming from

multiple southerly directions during the days of the high

emissions levels and while the wildfires to the south were

burning.

Conclusion

Based on the suite of evidence provided, including MODIS

imagery, HYSPLIT back trajectories, surface wind speed and

wind direction data, and no evidence of significant unusual

sources of anthropogenic PM2 .5 (as discussed in the Not

Reasonably Controllable or Preventable section of this

analysis), the EPA concludes that there is a clear causal

connection between the Peterson School monitor values in

Klamath Falls, Oregon for the days listed in Table 2 of this

analysis and the multiple wildfires, primarily the Bagley

Complex fire in California, that occurred during the summer of

2012.

• The event is

associated with

measured

concentrations in

excess of noulial

historical

fluctuations

including

background. 40 CFR

50.14 (c)(3)(iii)(C)

When reviewing summertime PM2 .5 values from 2000-2011 at

the monitor, there were 27 days over the standard, all of which

ODEQ attributed to wildfires (Table 5).

The average PM2 .5 concentrations during the summertime

period between 2000-2011 is 8.1 pg/m3 . If the abovementioned exceedances attributed to wildfires are removed

from the dataset, the average lowers to 6.8 ,ag/m3 (page 23).

The data shows that with or without wildfires the summertime

average is generally very low.

The ODEQ compared the PM2.5 concentrations on the days it is

claiming as exceptional events to summer concentrations

during low wildfire years. For the low wildfire years, the 990'

percentile high concentration was 17.4 ug/rn3. The requested

days' concentrations were well over the 99th percentile high

concentration and this demonstrates that they exceeded

historical fluctuations. Table 6 in the submittal also identifies

that 90 percent of summer days fall below 12 iag/m 3 further

supporting lower summer concentrations.

Based on the presented data, the EPA concludes that the values

listed in Table 2 are in excess of normal historical fluctuations,

including background.

• There would have

been no exceedances

To show there would have been no exceedances "but for" the

event, the ODEQ demonstrated that the average summertime

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"but for" the event.

40 CFR

50.14(c)(3)(iii)(D)

PM2 .5 values for the 2000-2011 period were relatively low at

8.1 pg/m3 , and at the lower 6.8p.g/m3 level with suspected

wildfire events removed (page 22). It then showed a clear

causal relationship between the wildfires and the elevated

PM2.5 values at the monitor through the analysis in the clear

causal relationship section. The ODEQ also showed that there

were no other significant sources of PM2,5 that would have

contributed at the time or in the quantity needed to result in the

elevated values that were recorded at the monitor during this

time period.

ODEQ compared the requested days' concentration to 7 recent

years of summer concentrations during low wildfire years. For

those 7 years, the 99`h percentile high concentration was 17.4

pg/m3 . The requested days' concentrations of 28.1 jg/m3 , 43.2

μghn3 , and 34.1 μg/m3 were well over this 99th percentile high

concentration and demonstrated that they exceeded historical

fluctuations.

As stated above, the ODEQ discusses that there were no

unusual anthropogenic sources of emissions during this period.

Given this, the EPA concludes that but for the wildfires in and

around Oregon in the summer of 2012, there would have been

no exceedances of the 24-hour PM 2.5 NAAQS at the monitor in

Klamath Falls, Oregon.

• Mitigation, 40 CFR

51.930

As described in the not reasonably controllable or preventable

section above, a significant amount of financial and human

resources were invested in containment of the multiple fires in

and around Oregon in 2012.

Additionally, multiple agencies and organizations in Oregon

utilized a wildfire response protocol to organize state response

efforts and responsibilities (Section 8.2.1). This includes

management and use of the Oregon Smoke Blog.

The ODEQ also maintains an air quality index website to

communicate ongoing air quality levels and issues health

advisories through the web and via email during prolonged

(72+ hours) unhealthy air quality periods. Appendix A

includes news releases on unhealthy air quality levels for the

2012 events. The ODEQ took mitigation actions to protect

health from elevated particulate matter levels related to these

exceptional events.

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Conclusion

Based on the documentation submitted by the ODEQ on November 12, 2014, the EPA concurs with the

exceptional events flags for the three days listed in Table 2, which have been flagged by the ODEQ in

AQS as exceptional events.

Table 2. Dates and Values Concurred on by EPA

Klamath Falls Monitored Values

i Date PM2 .5 concentration (ig/m')

AQS site 41-035-0004 POC1

8/25/2012 28.1

8/28/2012 43.2

8/31/2012 34.1

The information and analyses presented in the ODEQ's exceptional event demonstration package

provided a weight of evidence sufficient for the EPA's concurrence on the flagged data from the monitor

on the dates listed in Table 2 above and as described in this document. Accordingly, we are placing a

concurrence indicator in the EPA's AQS database for these dates at this monitor.

Note that the EPA's decisions on exceptional event exclusions are not considered final agency action

until they are acted upon as part of a final regulatory action subject to public notice and comment. Such

actions would include, for example, decisions to exclude the affected data from use in an approval of a

non-attainment plan, maintenance plan or other regulatory decision.

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