Understanding the Critical Loads Approach: Protecting Clean Air and Air Quality Related Values

1. Understanding the Critical Loads Approach WESTAR Workshop November 2005

2. Protecting Clean Air and Air Quality Related Values: PSD and Other Mandates • PSD program was intended to protect against effects that may occur notwithstanding attainment of NAAQS preserve, protect and enhance the air quality in national parks, national wilderness areas, national monuments, national seashores, and other areas of special national or regional natural, recreational, scenic, or historic value.” Independent and complimentary FLM mandates to conserve natural and cultural resources “unimpaired” for the enjoyment of future generations.

3. Success is … • Economic growth occurring without compromising clean air, especially in national parks and wilderness areas • Effective protection of air quality and resources affected by air quality in Class I and II areas

4. Is It Working? • Technology-forcing requirements have limited pollution increases • FLMs knowledge of how air pollution affects resources has increased signifcantly, but is far from complete • Efforts to MANAGE the clean air resource are primarily limited to NSR • “Periodic” review of increment consumption hasn’t occurred in most states • Air quality in many Class I areas is deteriorating and scenic and natural resources are experiencing adverse effects • Framework doesn’t fit the problems occurring

10. EFFECTS OF ATMOPSHERIC DEPOSITION • Forms: Wet (rain, snow), dry and clouds • Acidifies soils and surface waters • Changes soil processes • Can cause eutrophication (nitrogen only) • Causes shifts in plant community composition and diversity (nitrogen only) • Increase in native or exotic grasses, other invasive plants • Altered fire cycles (due to greater fuel loads caused by N fertilization) • Increased susceptibility to pests and other stresses • Increases availability of aluminum (which can be toxic to plants and animals)

11. Purposes of PSD Program More Likely to be Achieved thru… • More attention to cumulative impacts on ENVIRONMENT • improved partnership between FLM & States, including shared recognition of value of assessing and addressing cumulative impacts on AQRVs • More direct link between regulatory framework and desired outcome

12. Critical Load Approach Links Air Quality Management to Ecological Effects • “Critical loads” define desired condition: • “The quantitative estimate of an exposure to one or more pollutants below which significant harmful effects on specified sensitive elements of the environment do not occur according to present knowledge.” (Nilsson and Grennfelt 1988) • “Target loads” to track progress: • The level of exposure to one or more pollutants that results in an acceptable level of resource protection; may be based on political, economic, or temporal considerations.

13. Scientific Approaches to Develop Critical Loads • NPS research on sensitive receptors and endpoints ongoing at: • Rocky Mountain NP, Glacier NP, Yellowstone NP, Grand Teton NP, Great Sand Dunes NP • Shenandoah NP, Great Smoky Mountains NP • Mount Rainier NP, North Cascades • Big Bend NP, Joshua Tree NP • Modeling being tested at: • Rocky Mountain, Great Smoky, Mt Rainier, Acadia and Joshua Tree • Other FLMs also conducting empirical studies and modeling to establish critical loads

14. FLM Future Directions • Increased communication and collaboration between land managers and scientists on resource management needs, sensitive resources, relevant indicators and endpoints to meet resource protection goals. • Identify/refine appropriate models for estimating critical loads in both aquatic and terrestrial ecosystems • Using critical loads as a resource management tool and performance measure • Defining desired conditions • Assessing current conditions and tracking progress • Explore opportunities for using critical loads in air regulatory planning processes at the national, state, and local level thru a cooperative conservation approach • “EPA recognizes that a State may choose to utilize a critical load concept as part of its air quality management approach to meet its broader air quality goals.” EPA NOx Increment Rule (2005)

15. WESTAR PSD New Framework Ira Domsky, Deputy Director Air Quality Division, Arizona DEQ November 15, 2005

16. Overview • Review of guiding principles • March 31-April 1, 2005 Workshop • The path forward • Major issues related to critical loads

17. Guiding Principles • Achieve the purposes of the PSD program • Protect public health and welfare • Preserve, protect and enhance air quality in Class I and other areas of natural and recreational significance • Assess and manage interstate impacts • Comply with spirit and requirements of PSD permitting processes

18. Guiding Principles • Look beyond existing law, if warranted • Improvement to environment and efficiency • Evaluate feasibility and balance competing values • Harmonize with and complement other regulatory requirements • Incorporate new knowledge and technologies and analytical tools

19. March 31 – April 1 2005 Workshop Attendees • Nearly all states • EPA • NPS for FLMs • WESTAR staff and contractor

20. Issue Mapping • Procedure used for all topic areas • Brainstorm and record – questions, questions, questions • Categorization • Organization • Develop action plan

26. Categories of Issues • Methods, analysis and goals • Roles • Program design • Implementation approach – cap & trade • Resources • Political feasibility • Impacts on sources/equity • Environmental benefits/impacts

27. Major Themes • Mandatory Class I area AQRVs • Effects based AQRV protection (e.g., critical loads) • Non-mandatory Class I, Class II/III areas • 2 options • Change focus from short-term to annual • Alternative without increments • Approach dependent on outcome of Class I process

28. Major Themes • Baseline emissions inventory improvement • 2 options • Secure, stable baseline inventories • Reset baseline dates

29. Caveats • Process for defining specifics for new frameworks will take at least 18 months • Follow-through is essential • Time the roll-out to assure positive outcome

30. Critical Loads Related Issues • Time frame for development of critical loads (CLs) • What pollutants should be assessed? • Will CLs replace increments? • If so, how will transition work? • Can surrogates be developed (e.g., visibi-lity thresholds, weight of evidence)?

31. Critical Loads Related Issues • Stopping point for assessment • Incorporation of new science • Will CLs be “bright line” standards? • Handling of source apportionment and setting of emissions goals/limitations • Dealing with short-term v. long-term impacts

32. Critical Loads Related Issues • Development of “research program” • Implementation time frames for problem identification and responses • Can nonattainment area plan be a model? • Integration into permitting programs • Dealing with potentially competing AQRVs

33. Critical Loads Related Issues • Program evaluation • Addressing background levels and natural events • Institutional relationships – Federal, State, Tribal, RPO • Role of cap-and-trade programs and their implementation