Exceptional Events: A California Perspective Karen Magliano, Chief Air Quality Data Branch Planning and Technical Support Division

Guiding Principles Allow planning efforts to focus on what is controllable Allow planning efforts to focus on what is controllable Recognize recurrent nature of natural events Recognize recurrent nature of natural events Require level of documentation commensurate with the complexity of the event Require level of documentation commensurate with the complexity of the event Consider what are “reasonable and appropriate” control measures in context of event Consider what are “reasonable and appropriate” control measures in context of event 2

Focus of Planning Efforts Recognize a hierarchy of events: Recognize a hierarchy of events: Makes a difference between attainment and nonattainment Makes a difference between attainment and nonattainment Affects design values and classifications Affects design values and classifications 3

Natural Events Not reasonably preventable or controllable Not reasonably preventable or controllable Can recur Can recur Regardless of frequency, are not controllable Regardless of frequency, are not controllable 4

Practical Approach to Documentation Level of documentation should depend on complexity of event Level of documentation should depend on complexity of event Widespread, extreme events: Widespread, extreme events: Less documentation to fulfill weight-of-evidence approach Less documentation to fulfill weight-of-evidence approach Example: Large-scale wildfires or regional/high winds Example: Large-scale wildfires or regional/high winds More complex events: More complex events: More detailed documentation More detailed documentation Example: Distant, smaller fires or micro wind events Example: Distant, smaller fires or micro wind events 5

Special Ozone Considerations More complex—not direct relationship like PM More complex—not direct relationship like PM Wildfires typically occur during ozone season Wildfires typically occur during ozone season In some cases may exacerbate rather than “cause” an exceedance In some cases may exacerbate rather than “cause” an exceedance May require more qualitative analysis May require more qualitative analysis 6

Assessing ‘Reasonable and Appropriate’ Control Measures Determine on an event specific basis Determine on an event specific basis Consider relative contribution of sources Consider relative contribution of sources Consider potential emission reductions and cost- effectiveness of further control Consider potential emission reductions and cost- effectiveness of further control 7

Types of Events in California Wildfires Wildfires High Winds High Winds Fireworks Fireworks 8

Case Study 2008 Northern California Wildfires June to August, 2008 Over 2,000 individual fires 1.2 Million Acres Burned NAAQS Exceedances PM2.5 PM10 Ozone

Smoke from wildfires covers Northern California

Wildfire News Coverage Yosemite/ Sacramento/

CBS Video Clip – 06/24/08

Photos – 2008 Wildfires AP photo/

Wildfire PM Concentrations 7/25 7/8 - 7/12 6/24 - 6/28 All PM2.5 BAM Sites in Northern California

Wildfire PM Statistical Analysis

Wildfire Ozone Concentrations 6/27 7/8 – 7/9

Wildfire Ozone Comparison

Wildfire Ozone Statistical Analysis 7/9 6/27 7/8

Case Study San Joaquin Valley High Wind Event May 21-22, 2008 Wind Gusts up to 48 mph NAAQS Exceedances PM10

High winds impact San Joaquin Valley

High Wind News Coverage Turlock – May 2008

Photos High Wind Event

High Wind PM Concentrations

Summary Exceptional Events Rule is in place to identify events beyond planning process control Exceptional Events Rule is in place to identify events beyond planning process control Events should not drive the planning process Events should not drive the planning process Flexibility needed based on nature and complexity of events Flexibility needed based on nature and complexity of events