**Appendix W Refresher Tyler Fox** **9 th** **Conference on Air Quality Modeling October 9, 2008** **Newsflash • Promulgation of AERMOD Modeling** **System in November 2005 – Federal Register notice published Dec 9,** **2005 • As of December 9, 2006, AERMOD is fully** **promulgated as a replacement to ISC3, in accordance with Appendix W.** **– See SCRAM for more information at: http://www.epa.gov/scram001/dispersion_pref** **rec.htm Outline** **• Reflect back on . . . – 8** **th Modeling Conference** **• Vision and Essential Elements – RO call for improved support** **• AERMOD Development & Maintenance • CALPUFF Model Update Protocol** **• R/S/L Workshops • Modeling Clearinghouse** **• Clarification Memos (Roger Brode) • Importance of Process** **Dispersion Modeling Futures: Vision Statement** **“Lead and promote collaborative efforts on near-field air quality modeling to** **improve source culpability assessments”** **First Essential Element Foster a collaborative environment** **aimed at strengthening our technical expertise and working relationships** **across EPA, other Federal agencies, and the scientific community to regain** **our leadership role and promote use of best science and evaluation methods.** **Fourth Essential Element Promote a community approach to** **model development and acceptance that champions the use of best science,** **supports continual improvement in modeling science and data, and timely** **model acceptance for use in regulatory arena.** **Need for Improved Modeling Support • In May 2006, the ROs presented two** **recommendations to the Air Division Directors:** **– OAQPS needs to enhance its technical expertise regarding the “new generation” of** **near-field models – OAQPS needs to accelerate its reinstatement** **of an active and effective Model Clearinghouse to provide technical expertise** **for permitting and SIP applications • OAQPS has responded and taken actions** **AERMOD Modeling System: Development and Maintenance** **• AERMOD Implementation Workgroup –** **Built upon initial AERMOD Implementation Group – Apr il 2005 to April** **2006 (See A. Cimorelli presentation at 8 th** **Modeling Conf) –** **Inaugural AIWG Conference Call in January 2007 with Roger Brode and** **Randy Robinson as co-chairs –** **Composed of State, Local, EPA Regions, EPA HQ with 3 State led** **subgroups on MET issues, surface characteristics, a nd urban** **improvements. –** **Collaborative and inclusive process that relies on the experience and** **knowledge of model users in the states and regions to advise OAQPS** **on implementation issues and priorities for resourc es.** **• Re-instituted AERMIC to guide OAQPS on science** **issues –** **AMS/EPA Regulatory Model Improvement Committee init ially** **formed in 1991; charged to develop replacement for ISCST** **based on state-of-the-science; AERMOD promulgated D ec.** **2006 • New AERMIC committee met in RTP during March,** **2008 and July, 2008 • Membership of “new” AERMIC committee:** **• Roger Brode, OAQPS, Co-chair • Jeff Weil, CIRES-NCAR, Co-chair** **• Akula Venkatram, UC-Riverside • Al Cimorelli, EPA Region 3** **• Bret Anderson, EPA Region 7 • Vlad Isakov, EPA/ORD/AMD** **New AERMIC CALPUFF Update Process** **• Incumbent upon EPA to perform an independent assessment of CALPUFF** **when updating to new versions • CALPUFF requires extensive assessment** **and understanding of changes made; approvals made by EPA, not developer** **• CALPUFF Update Tool – Introduced at 8 th** **Modeling Conference in Sept 2005 CALPUFF Update Tool** **• Compares 2 CALPUFF versions; proposed (beta) vs. current version (base)** **• Determines differences in results across 10 scenarios, including a range of domains, met** **inputs and sources • Provides a standardized methodology for** **assessing consequences from changes in model codes** **• EPA has successfully applied as part of updates: – Version 5.7 to 5.711a (Dec 2005)** **– Version 5.711a to 5.8 (June 2007) Role of R/S/L Workshops** **• Appendix W includes the following references to EP A** **regional workshops: – “Historically, three primary activities have provi** **ded direct input to revisions of the** Guideline**. The first is a series of annual EPA workshops conducted for the purpose of** ensuring consistency**and**providing clarification**in the application of models.” [Preface, paragraph (b)]** **– “From time to time situations arise requiring**clarification of theintent of the guidance**on a specific topic. Periodic workshops are held with the headquarters, Regional Office, St** **ate, and local agency modeling representatives to** ensure consistency**in modeling guidance and to promote the use of more ac** **curate air quality models and data bases. The workshops serve** **to provide further explanations of Guideline requirements to t** **he Regional Offices and workshop reports are issued with this** clarifyinginformation**.” [Paragraph 1.0(f)] – “Two additional** sources of modeling guidance**are the Model Clearinghouse and periodic Regional/State/Local Mod** **elers workshops.” [Paragraph 3.0(a)]** **History of R/S/L Workshops • EPA’s 2008 Regional/State/Local Modelers** **Workshop was held on June 10-12, 2008 in Denver, CO** **• This was the 30 th** **R/S/L Workshop, beginning with 1978 but skipping one year** **• Attendance was limited to OAQPS & Regional Modeling Contacts in the beginning, but now** **includes State & local agencies • 2008 attendance was about 90 total, including** **all 10 EPA Regional Offices, 29 States, 5 local agencies, and 5 FLMs** **• Presentations since 2005 are available from SCRAM at:** **– http://www.epa.gov/scram001/conferenceindex.htm Model Clearinghouse** **• What is it? – A process and mechanism by which an EPA Regional** **Office can obtain EPA Headquarters concurrence on implementation issues related to air quality modeli** **ng. • Statutory authority?** **– Appendix W, Section 3.3(b): “As appropriate, Regi onal** **Office may request assistance from the Model Clearinghouse after an initial evaluation and decis** **ion has been reached concerning the application of a** **model, analytical technique or data base in a parti cular** **regulatory action. Model Clearinghouse Goals** **• Provides national consistency in regulatory decisions** **• Timely interpretation of guidance (as issues arise)** **• Minimizes bad precedents: – Get in early on issues** **– Memoranda provide essential support to regions, states and locals** **• Guidance development through consensus building** **MC Operation • Technical issues** **– Response provided by OAQPS/AQMG and other technical experts with review by policy** **staff • Policy issues (if submitted to MC)** **– Referred to New Source Review Group – Response provided by OAQPS/Air Quality** **Policy Division (Bill Harnett, DD) with technical inputs as appropriate** **• As appropriate, MC responses may be reviewed by OGC** **Formal Clearinghouse Process • State contacts Region** **• Region writes memo to clearinghouse: – Statement of Issue** **– Desired approach – Justification** **• Clearinghouse facilitates solutions and writes for mal** **response • Clearinghouse summarizes & archives decisions:** **– Searchable database (MCHISRS) via web access (SCRA M)** **– Present summary at annual Regional/State/Local wor kshop** **– Write annual report • OAQPS develops guidance as appropriate:** **– Policy memo, EPA Report, Rule Making Model Clearinghouse Information** **Storage and Retrieval System (MCISRS) • Old MCHISRS system** **– Only searchable by those who have an “epa.gov” address** **– Formal memos and MCHISRS records are separated on SCRAM** **• New MCHISRS system (as of 5/10/07) – Allows full public access so restriction to “epa.g** **ov” eliminated** **– Links MCHISRS records to the formal MC memoranda – Searchable by topic, pollutant, RO, fiscal year, m** **odel, etc.** **– http://www.epa.gov/scram001/guidance_ clearinghouse.htm** **Importance of Process • Importance of Model Clearinghouse process has** **been stressed recently, especially with promulgation of CALPUFF and AERMOD** **– Emphasis on formal process of Regional Office pres enting** **issue to Model Clearinghouse, perhaps initiated at State level,** **with full background information and RO position – Informal contacts with OAQPS staff do not constitu** **te “consulting with the Model Clearinghouse”** **• Importance of “Modeling Protocols” to get review and input early in the process (EPA & FLMs)** **• Respecting the roles of various parties/stakeholde rs** **– Applicant – Reviewing authority (RO or State)** **– OAQPS as needed, with both technical (AQMG) and po licy** **(AQPD) perspectives – Public** **Importance of Process • Importance of consistency is stressed several** **places in Appendix W, including the very first sentence:** **– “Industry and control agencies have long expressed a need for** **consistency in the application of air quality model s for regulatory** **purposes.” • Clarify distinction between regulatory modeling** **applications, which fall under purview of Appendix W,** **and non-regulatory applications, such as risk assessments** **– “The Guideline recommends air quality modeling tec hniques that** **should be applied to State Implementation Plan (SIP ) revisions for** **existing sources and to new source reviews (NSR), i ncluding** **prevention of significant deterioration (PSD). Appl icable only to** **criteria air pollutants, it is intended for use by EPA Regional Offices** **in judging the adequacy of modeling analyses perfor med by EPA,** **State and local agencies and by industry.”**