EPA Region 10

Review of Exceptional Event Request 2013 Klamath Falls, Oregon 24-hour PM2.5 NAAQS Dates Analyzed: July 30, 2013 and August 5, 2013

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 two days for the Peterson School monitor (Klamath Falls, Klamath County Oregon, AQS site 41- 035-0004 FOCI); herein this will be referred to as "the monitor." The recorded 24-hour PM 2.5 levels for the monitor ranged from 74.8

,LLg/m3 to 79.8 ug/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 evaluation and concurrence.

Table 1. Dates and Values Flagged by ODEQ

Klamath Falls Monitored Values Date PM25 concentration (μg/m 3 )

AQS site 41-035-0004 POCI 7/30/2013 79.8 8/5/2013 74.8

PM 2

, 5 levels from submitted days led to exceedance of the 35μg/m 3 24-hour PM2.5 NAAQS and violation of the 2012-2014 design value for the 24-hour PM2 .5 NAAQS. Documentation provided by the ODEQ demonstrates that there were multiple wildfires occurring in Oregon and California in the summer of 2013, notably the Douglas Complex fire in Oregon.

The ODEQ flagged the monitored values as wildfire exceptional events before the statutory deadline of July 1, 2014. 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 two dates at the site. The ODEQ is requesting concurrence from the EPA on both 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 both values would be used in a regulatory determination and the EPA has, therefore, evaluated both 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 2013 elevated PM2.5 values as wildfire exceptional events in the EPA's AQS database prior to the July 1, 2014 deadline.

• The public had an opportunity to review and comment on the demonstration justifying 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 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, 2016).

Technical Criteria:

• The event satisfies Conceptual Model the criteria in 40 The ODEQ developed a conceptual model that shows how CFR 50.1(j) (i.e., wildfires in Oregon and California, especially the Douglas affects air quality, is Complex fire in Oregon, affected air quality in the Klamath not reasonably Falls area during the summer of 2013. In 2013, a number of controllable or fires burned approximately 350,786 acres in southwestern preventable, is an Oregon. In neighboring California, wildfires burned event caused by 577,675 acres (p 10 and Table 3). In August 2013, weather human activity that conditions in Oregon were hot and dry, typical of the summer is unlikely to recur at periods (Figures 2, 3, 6). The combination of hot and dry

2a particular location

or a natural event, and is determined by EPA to be an exceptional event). 40 CFR 50.14(c)(3)(iii)(A) conditions made the area more susceptible to wildfires (Figure

12). The ODEQ demonstrated that elevated emissions at the monitor were due to direct impact from the Douglas Complex wildfire smoke plume. Other nearby wildfires were also generating emissions (Figure 17).

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 2013, wildfires burned 350,786 acres in Oregon (Table 3), and multiple wildfires burned in the summer of 2013 in areas impacting the monitor. As shown on Table 1, elevated values ofPM2

, 5 occurred in late July and early August 2013.

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 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 2013, wildfires burned 350,786 million acres in Oregon. In late July and August 2013 weather conditions in Oregon were hot and dry, typical of the summer periods (Figures 2, 3, 6). The combination of hot and dry conditions made the area more susceptible to wildfires (Figure 13).

While there were multiple wildfires in Oregon and surrounding states in the summer of 2013, Klamath Falls was primarily affected by the Douglas Complex fire in Douglas County. This fire complex was located 100 miles to the northwest of Klamath Falls. The Douglas Complex fire ignited by lightning on July 27, 2013, burned 48,679 acres, cost an estimated $55 million to control, and was controlled over a month later on September 3, 2013. Table 11 identifies that 2,652 people were part of the response effort. It was managed using the Oregon Department of Forestry management strategy (page 18) and was physically controlled by Oregon Department of Forests

3and the Douglas Forest Protective Association under full suppression control methods (page 20).

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 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 July and early August 2013 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.

• 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 Douglas Complex fire in Oregon located 100 miles to the northwest of Klamath Falls. The ODEQ also identified multiple other fires in the surrounding area during the summer of 2013.

The ODEQ documented the direct connection between the fires and the monitor using MODIS satellite images, HYSPLIT back trajectories, and wind/temperature data.

Figure 41 shows a graph including wind speed, emissions levels, and wind directions. It shows that the winds were coining from the northwest (the direction of the Douglas Complex and Big Windy Complex fires) 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 supports this by showing the trajectory of the plumes from the Douglas and Big Windy Complex fires moving towards Klamath Falls on the high emissions days (Figures 43, 44, 45, 46, 47). Satellite imagery, Figure 40, show the plume from the Douglas Complex fire, as well as from the Big Windy Complex fire and fires in northern California, heading eastward toward nearby Klamath Falls. Wind roses in Figures 48 and 49 also support that winds were coining from the northwest during the days of the high

4emissions levels and from the area where the fires were burning.

Conclusion Based on the suite of evidence provided, including MODIS imagery, HYSPLIT back trajectories, surface wind speed and wind direction data, pressure gradients, and no evidence of unusual sources of anthropogenic PM 2.5 (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 Douglas Complex fire with contribution from the Big Windy Complex fire and fires in Northern California, that occurred in Oregon and surrounding states during the summer of 2013.

• The event is associated with measured concentrations in excess of normal historical fluctuations including background. 40 CFR 50.14 (c)(3)(iii)(C) When reviewing summertime PM 2.5 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 PM? s concentrations during the summertime period between 2000-2011 is 8. I ug/m 3 . If the above mentioned exceedances attributed to wildfires are removed from the dataset, the average lowers to 6.8μg/m 3 (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 99 th percentile high concentration was 17.4 p.g/m 3 . The requested days' concentrations were well over this 99th percentile high concentration and demonstrated that they exceeded historical fluctuations. Table 6 in the submittal also identifies that 90 percent of summer days fall below 12 μ.g/m' 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 "but for" the event. 40 CFR 50.] 4(c)(3)(iii)(D) To show there would have been no exceedances "but for" the

event, the ODEQ demonstrated through historical fluctuations that the average summertime PM- . s values for the 2000-2011 period were relatively low at 8.1 μg/rn 3 , and at the lower 6.8μg/m3 level with suspected wildfire data removed (page 22). It then showed a clear causal relationship between the

5wildfires 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 seven recent years of summer concentrations during low wildfire years. For those seven years, the 99 th percentile high concentration was 17.4 μg/m 3

. The requested days' concentrations of 79.8 1_tg/m 3 and 74.8 pg/m3 were well over this 99th percentile high concentration and demonstrated that they exceeded historical fluctuations.

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 2013, there would have been no exceedances of the 24-hour PM2.5 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 2013.

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 Biog.

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 2013 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 these two 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 Date PM2 .5 concentration (μg/m 3 )

-

AQS site 41-035-0004 POC1 7/30/2013 79.8 8/5/2013 74.8

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-attaimnent plan, maintenance plan or other regulatory decision.

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