How Ozone is Regulated under the Clean Air Act

1. How Ozone is Regulated under the Clean Air Act Darcy J. Anderson AZ Dept. of Environmental Quality

2. Presentation Outline • 8-Hour Ozone Standard – Background / Timeline • 8-Hour Ozone Standard – Designation Process • Arizona Designation Process – Examples • Potential Impacts of 8-Hour Ozone Designations on Tribes • Next Steps in 8-Hour Ozone Process

3. 8-Hour Ozone Standard – Background / Timeline • July 1997: EPA issued revised 8-hour health-based standard for ozone. • New standard 0.08 ppm averaged over 8 hours. Pre-1997 ozone standard 0.12 ppm averaged over 1 hour (40 CFR §§ 50.9 and 50.10) • Studies show that long-term, low exposure to ozona as harmful to human health as short-term, high exposure. • New standard more protective for longer exposure

4. 8-Hour Ozone Standard – Background / Timeline • 2000: EPA issues guidance documents “Boundary Guidance on Air Quality Designations for the 8-Hour Ozone National Ambient Air Quality Standards” and “Guidance on 8-Hour Ozone Designations for Indian Tribes” • See http://www.epa.gov/ttn/naaqs/ozone/ozonetech/#newstd and http://www.epa.gov/airprogm/oar/tribal/tribe8hd.html

5. 8-Hour Ozone Standard – Background / Timeline (cont.) • February 2001: Following court challenge, • U.S. Supreme Court upheld 8-hour ozone standard • Directed EPA to develop an implementation approach that blends CAA Title I, Part D, Subpart 1 and 2 requirements • (Whitman v. American Trucking Association, U.S. Supreme Court, Nos. 99-1257, 99-1426, February 27, 2001)

6. Comparison of Ozone Standards *Because of rounding convention, 0.085 ppm considered level of violation

7. 8-Hour Ozone Standard - Designation Process • November 2002: As part of lawsuit settlement, EPA and environmental groups agree on schedule for EPA to promulgate 8-hour ozone designations (April 15, 2004–See 67 FR 70070) • See http://www.epa.gov/ttn/naaqs/ozone/ozonetech/

8. 8-Hour Ozone Standard - Designation Process (cont.) • February 27, 2003: EPA memorandum on 8-hour ozone designations extends deadline for states to submit recommendations for designating areas from April 15, 2003 to July 15, 2003 • See http://www.epa.gov/ttn/naaqs/ozone/ozonetech/

9. 8-Hour Ozone Standard - Designation Process (cont.) • June 2003: EPA proposes rule for implementing 8-hour NAAQS • See text of proposed rule at http://www.epa.gov/airlinks/airlinks4.html • Final rule for implementing 8-hour NAAQS expected early 2004

10. 8-Hour Ozone Standard - Designation Process (cont.) • July 15, 2003: State recommendations for area designations submitted to EPA • see www.epa.gov/oar/oaqps/glo/designations/index.htm • Tribes could also submit recommendations by this date • Options: attainment / unclassifiable or nonattainment

11. 8-Hour Ozone Standard - Designation Process(cont.) • Governor’s recommendation for Arizona submitted to EPA in July 2003 • Analysis included looking at monitoring data, location of emission sources, meteorology, geography, population, traffic and commuting patterns, jurisdictional boundaries • Recommended all areas of state attainment / unclassifiable for 8-hour standard except Phoenix metro area • No state jurisdiction / recommendation for Indian reservations • Some Arizona tribes submitted their recommendations

12. Arizona Designation Process – Examples • Monitoring data – exceedances, violations • Location of emission sources • Meteorology, geography, and jurisdictional boundaries • Population • Traffic and commuting patterns

17. Meteorology, Geography and Jurisdictional Boundaries

20. Potential Impacts of 8-Hour Ozone Designations on Tribes • Boundary / background / transport • Tribes can provide valuable ozone data for urban nonattainment areas • Tribes can conduct additional ozone and NOx monitoring to assist with model verification • Public information / outreach (API) • Ozone mapping – AIRNOW

21. Next Steps in 8-Hour Ozone Process • February 6, 2004: Revised nonattainment area recommendations due to EPA • EPA looking at 2003 ozone monitoring data to determine effect on recommended area designations • Designations and classifications published in FR by April 30, 2004 (signed by April 15)

22. Next Steps in 8-Hour Ozone Process: Ozone Implementation Plan • June 2, 2003 - EPA proposed rule to implement 8-hour NAAQS (68 FR 32802) • August 6, 2003 - Draft rule text made available (68 FR 46536) • Possible options for implementation – CAA Subpart 1 or subpart 2 • Option 1: All areas under subpart 2 (Classify 8-hour nonattainment areas based on 8-hour design values) • Option 2: Separate areas based on whether they meet the 1-hour standard (Regulate areas generally meeting the 1-hour standard under Subpart 1 and areas generally exceeding the 1-hour standard under Subpart 2) • Subpart 1 - more flexible, minimal mandated controls (max attainment dates 5 or 10 years after designation) • Subpart 2 - proscriptive (attainment dates based on classification [marginal, moderate, serious, etc] consistent with subpart 2 provisions, i.e., 2007, 2010, 2013, 2019)

23. Next Steps in 8-Hour Ozone Process: Ozone Implementation Plan (cont.) • Anticipate implementation of new standard for Phoenix area either under subpart 1 or marginal under subpart 2 • Subpart 1 option - Attainment demonstration due 2007; attainment required 2009 • Subpart 2 option – Attainment required 2007 • New control measures may be necessary to meet proposed attainment date

24. Next Steps in 8-Hour Ozone Process: NOx Waiver • Draft rule proposes NOx waiver provisions under CAA Section 182(f) apply to any area designated nonattainment for 8-hour standard; • Requires new analysis to obtain waiver under 8-hour guidance • NOx control for RACT required for moderate and above areas under subpart 2 option, unless EPA approves NOx waiver • NSR & RACT requirements for major stationary VOC sources also apply to all major NOx sources unless NOx waiver provision implemented