the superiority and demonstrable conclusions of McRae's and Russell's work, which further buttressed legislative and policy plans for the state's environmental strategy. McRae pointed out one of the essential ingredients in this vindication of their model: their determination to certify the work as solid science. "[The industry modelers] simply claimed their conclusions without exposing the details of the calculations to scientific peer review," McRae was quoted as saying (Schneider, 1990, p. 44). McRae and his colleagues, however, invited the test of scientific scrutiny by publishing their results in an established journal (Milford et al., 1989). Although purely scientific, that paper indicates the nature of pollution politics and reads like a manifesto for change, based on the strong demonstrative evidence developed by the authors from the model of Los Angeles. The following paraphrase of that paper matches the tone and summarizes the contents of the published version:

The Problem. More than half of the people living in the United States reside in areas where ozone concentrations exceed the National Ambient Air Quality Standard of 0.12 ppm mandated by the U.S. government, and many cities, like Los Angeles, also fail to comply with the standards governing particulate matter (PM10) pollution. In the face of this shortcoming, science suggests that the standards should be even tighter, and many agencies already feel that they have exhausted the technical, political, and economically feasible control measures currently available to address the problem. Moreover, there is a growing awareness that the scope of the problem is not fully captured by the historical convention of concentrating on cities, since recent evidence and modeling suggest downwind problems are sometimes more severe than in the areas whence the pollution was generated.

The Traditional Response. Given a mandated, numerical air quality goal, strategies to reduce ROG emissions to a level that leads to air that meets that standard have been evaluated for cost-effectiveness. The Empirical Kinetics Modeling Approach employs a simplified, single-cell trajectory formulation to model the impact of a number of possible ROG and NOx emission level combinations on the resultant ozone level, and then to derive a new ROG reduction goal. Lowering NOx has not been mandated (except in some jurisdictions such as California), since observations suggest that sometimes lower NOx can paradoxically lead to higher ozone. The model fails to incorporate the significance of other pollutants, such as gas-phase pollutants other than ozone, and particulate matter components less than 10 micrometers in diameter. Further, it is not clear whether peak ozone concentra-

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