Science and Technical Support Work Group's Position on AOI/AOV Papers

The Science and Technology Support Work Group has provided technical approaches to be used for implementing the new standards. This body of work has been presented in the Conceptual Model report and in numerous issue papers that STSWG developed in response to questions from other work groups.

The STSWG recommends using scientific methods to establish cause and effect relationships to solve the ozone and PM problems. It is recommended that the problem area be identified as the area of violation (AOV). It is realized that all or part of the cause of the problem may come from outside the AOV. Thus, it is recommended that appropriate technical approaches be used to identify the cause of the problem, and then establish the area of influence (AOI). Then the planning would continue by developing a set of appropriate and effective control measures that would eliminate the cause of the problem. This process provides decision makers with a greater degree of confidence that the controls that are implemented will be successful in eliminating the fundamental cause of the problem. STSWG recognizes that planning will always have inherent uncertainties, and has recommended the use of an iterative process which links observed data to the predicted changes in air quality.

Previous efforts have developed the concept of a Regional Air Management Partnership (RAMP) which would be responsible for the technical work to identify the AOVs and AOIs , and in some cases, recommend control measures that would be effective. This model was partially followed by the Ozone Transport Assessment Group (OTAG). In the past ozone nonattainment areas have been identified and various states and combinations of states had attempted to develop control plans to solve the problem. Some of these areas (e.g. Lake Michigan Air Directors) could be considered as the first level of RAMPs. But, in some areas the modeling process identified several other areas that were larger than the area covered by the modeling that potentially contributed to the ozone problem. OTAG was formed ( and functioned as a second level RAMP) to address these problems of transport across a large portion of the country. The OTAG process identified regional controls that would decrease regional ozone concentrations and assist in solving the ozone problems in the previously identified nonattainment areas.

Two recent non-STSWG issue papers have appeared that recommend mechanisms by which the EPA could move forward to address both ozone and PM nonattainment issues. STSWG believes that these papers do not fully reflect the technical processes that STSWG has suggested.

The first of these papers is from the EPA and is titled "The Regional Air Management Partnership (RAMP) and the Area of Influence (AOI) Process." The paper suggests that no RAMPS are needed for ozone and PM issues should be addressed with two RAMPs nationwide.

The second paper, "A Framework for Areas of Influence/Areas of Violation (AOI/AOV): Responsibility for Reaching Attainment," is a product of a small ad hoc group trying to resolve the problem of the present approach to nonattainment for the new ozone standard and for assumed nonattainment for the yet to be finalized PMFINE standard.. The Framework paper recommends that those areas which would be classified as nonattainment under the new standards make early reductions to improve air quality or even reach attainment prior to implementing a major SIP process. Among the assumptions in this Framework paper is the desirability of developing a presumptive list of control measures that should be implemented by the AOV in the years preceding the SIP process. The paper assumes that the AOV can be exempted from some control measures by using a set of simple criteria and will not need a rigorous SIP analysis to determine what measures are necessary.

The following nine points represent the STSWG concerns with the concepts outlined in these two papers:

1.	STSWG felt that neither paper supports the idea that the underlying foundation beneath EPA's air management process should be the use of adequate tools and databases (both modeling and economic) to establish the cause and effect relationship needed to solve the ozone and PMfine problems. STSWG has consistently recommended that there is a need to improve air quality models, economic models, databases, and data analysis techniques to ensure that planning decisions are effective.

2.	STSWG would like to recognize that a model's strength is in evaluating past episodes and not in making future predictions of meteorological events. This will always introduce uncertainty into the planning process and it is important that model limitations must be recognized in any planning exercise.

3.	STSWG supports the idea that an iterative process be utilized so that a midcourse correction may be made if necessary. Because of the uncertainties in the planning process, model predictions should be compared with ambient air quality measurements at some point in the future (e.g., five or six years after the adoption of the plan), and the effectiveness of the model and the control measures should be re- evaluated. This concept is also embedded in the Reasonable Further Progress issue paper.

4.	STSWG questions the recommendation that an AOV should implement a presumptive set of controls to address air quality issues for secondary pollutants. A method of presumptive controls may be adequate (but not necessarily cost- effective) in some cases for controlling primary pollutants and preclude the necessity of detailed modeling. However, presumptive controls should not be used for secondary pollutants unless sufficient scientific evidence is presented to demonstrate that these control measures will ameliorate air quality. Without understanding the complex non-linear chemistry producing ozone or secondary aerosols, no simple mechanism exists to judge if the presumptive controls will benefit air quality or provide cost-effective solutions. Controls which reduce ozone in one area may not be effective in another region and they may not reduce PMFINE. For PMFINE, specific areas requiring more study include collection of speciated monitoring data, development of modeling techniques, and development of appropriate emissions inventories (for primary PMFINE, organic aerosols, and ammonia).

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5.	STSWG believes that continued technical analyses will be necessary to determine which control strategy choices are appropriate for control of ozone. From a technical perspective, there is a continued need to obtain air quality, emissions and meteorological data and carry out data analyses to better understand the local and regional scale formation of ozone . STSWG has recently stressed the need to consider the concept of a linkage between air quality models and economic models, such as the one developed by the Cornell Institute of Social and Economic Research in conjunction with the Department of Atmospheric Sciences at SUNY. STSWG believes that the economic models also need to undergo a rigorous evaluation of their underlying assumptions. program to address both local and transported ozone precursors.

6. STSWG feels that the results from a linked approach would be negated by the adoption of the recommendations in the RAMP/AOI and Framework papers. The concern is that there may be differences in the ranking of control measures (including the spatial nature of the measure) when considering strategies to maximize pollution reduction and minimize cost for the one- and 8-hour standards. Pursuit of a strategy that moves to meet the one-hour standard may be likely to show improvements in air quality with respect to the corresponding 8-hour standard. However, these controls may not be optimal for meeting the 8-hour standard. Implementation of a control program for the one-hour standard could adversely affect the liquidity of the market needed to devise a least-cost program for the 8-hour standard. Adoption of a set of presumptive controls would also have a negative impact by including options which would not be used in a least-cost approach.

7. The definitions and roles of RAMPs, AOVs/AOIs, and modeling centers should be stated explicitly in such a way that political entities will support rather than hinder the work of the scientific community. STSWG views RAMPs as political entities which identify technical people, establish the funding sources for the modeling centers, and approve the scientific findings. The decisions about where RAMP boundaries are established should not interfere with scientific investigations.

8.	STSWG feels that the OTAG process showed that multi-State planning can work, but OTAG did not operate as the type of RAMP described in the RAMP/AOI paper. The OTAG process was driven by an arbitrary time line which resulted in compromises when developing the underlying database and in planning the ultimate strategies. Although it was successful in terms of developing a scientific process, OTAG did not achieve a unanimous buy-in from all stakeholders regarding which solutions would be effective. In order to deal with the increasingly complex issues associated with the new PM and ozone standards, a cooperative process will be necessary which involves all stakeholders. OTAG and other groups, such as GCTVC and NARSTO, laid the foundation for future multi-state planning efforts.

Some members of STSWG felt that the RAMP process might be more successful if two levels of RAMPs are recognized. The first RAMP could be large and political in nature with the goal of directing the initial analyses and defining the AOIs and AOVs. The AOI and AOV boundaries would then define the second set of RAMPs, and each second level RAMP could proceed with the technical development and the assessment of planning tools and control strategies.

9.	STSWG does not agree with the automatic presumption that there is no need for ozone RAMPs. STSWG also questions the formation of exactly two RAMPs to address PM issues