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 PM 2.5 levels for the monitor ranged from 28.1 μg/m 3 to 43.2 μg/m 3 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/m 3 )

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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.

1The 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

2a 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 ofPM 2.5 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 PM 2.5 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

3in 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 PM 25 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

4supports 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/m 3 . 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 PM 2.5 concentrations on the days it is claiming as exceptional events to summer concentrations during low wildfire years. For the low wildfire years, the 99 0 ' 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

5"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/m 3 , and at the lower 6.8p.g/m 3 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/m 3

. The requested days' concentrations of 28.1 jg/m 3 , 43.2 μghn 3 , and 34.1 μg/m 3 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.

6Conclusion

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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