Implementation of Exceptional and Natural Events Policies and Rules in Arizona Ira Domsky, Deputy Director February 25, 2009

Overview of Presentation Arizona experience with exceptional events policies and the EPA rule Examples Special Issues Future Needs

Background Air Quality Exceptional and Natural Events Policy established in April 1999 State law EPA policy Technical Criteria Document focused on exceptional meteorology Revised in January 2006 to address regional natural events Revised in June 2007 to address EPA Exceptional Events Rule

Exceptional Event Demonstration Most events in Arizona are driven by meteorology – windblown dust Demonstration is complex Telling the story in a picture is both effective and efficient Format is based on tiles containing data, color, geographic relationships, images and a narrative

Key Elements Average and peak wind speeds in relevant areas of the State Ambient air quality data Satellite and camera images Event contribution analysis making the “but- for” assessment. Historical distribution to address exceptional nature of the event Narrative structure to address required elements of the EPA rule (CFR citations)

Arizona’s Evaluation Procedures Preliminary Review of event to determine validity of reading Gather input data from variety of sources and archive (met and ambient air quality data, forecasts, photograpic images, satellite maps, NWS advisories) Assemble Draft Assessment Report Stakeholder Meeting / Finalize Report Public Comment / Final Submittal

Documenting Exceptional and Natural Conditions AzMet, NWS, local winds/met (hourly) GOES-West Sat Images (hourly) Phoenix Vis Network Cameras (15-min) Hourly AQ data where available Excel integrated “Assessment Master” Links all sources Variety of “tiles” available Assembles into 11” x 17” format

Guided Tour of Arizona Document High wind event of July 19, 2007 Multiple exceedances in Phoenix NWS “tile” notes visual range and “Haze” Event contribution analysis shows NAAQS would have been met. Historical Distribution shows concentration well above 95 th percentile Required elements from EPA rule are cited in narrative

7/19 11PM Winds & Blowing Dust

Narrative & Concentration Graph

Satellite & Photographic Images

Event Contribution Analysis

Historical Distribution

What Does A Haboob Look Like? Wall of dust created from strong downdraft from the core of a very tall thunderhead See Video

Example of Non-flagged Event Higley monitor 10/9/2004 – high wind event. High winds in the southwest Valley. Subsequent investigation found potential existed that activity at nearby facility could have caused exceedance. Not flagged. Current practice is to fully document.

Public Process Initial Stakeholder outreach meeting Final report after stakeholder input. 30-day comment period on final report Final report forwarded to EPA with comments received

Partnering with Region 9 Active working relationship with Region IX on natural events. Concurrence received on some historical flags; recent flags pending Input from EPA staff instrumental in evolving the assessment tool and packaging of the assessment report

Specialized Issues Flagging of below-NAAQS values for Limited Maintenance Plan eligibility Flagging of International Transport issues at Nogales (stagnation/drainage from Mexico) Haboob type storms frequent Recent problems with BAMS monitors

Flagging Unreliable Data: BAMS Monitor Experience Several exceedances at Yuma BAMS in Flagged and explained in standard assessment format. Statistical examination of “paired-in-time” data with two co-located filter samplers (FRM & CoFRM) performed. Results showed BAMS is high-biased and statistically different than FRM; FRMs showed random variation and were statistically similar BAMS decommissioned and replaced with TEOM in 2007

YUMA BAMS vs CoFRM Errors

YUMA TEOM vs CoFRM Errors

YUMA and NOGALES BAMS Errors

BAMS Conclusion: BAMS do not produce representative data in the Yuma and Nogales areas. TEOM monitors agree much better with Filter based FRM.

Additional Issues Clarification of flagging non-exceedance values for LMP and what type of treatment will it be (old policy or EER) Need something “in writing” about any deficiencies in our analytical method, and clarity about acceptability of submittals.

For More Information Contacts: Shawn Kendall (602) Diane Arnst (602)