70 



to note that the transport region includes the entire area of all 

 member states. Until modeling and other impact analysis are 

 completed, the Commission will be unable to assign specific 

 source contributions to the problem. As a side note, the 

 Commission is also working with the Mexican government to develop 

 an inventory for assessing the potential impact of Mexican 

 emissions on the Colorado Plateau. 



The Commission is integrating several modeling approaches 

 into its analytical framework for assessing the relationship 

 between emission changes and visibility impairment. In addition, 

 it has undertaken an analysis as to why clear days exist on the 

 Colorado Plateau. This analysis will provide a response to the 

 CAAA of 1990 mandate to analyze the concept of clean air 

 corridors. It needs to be noted that the concept of clean air 

 corridors has often been translated into "no growth" corridors 

 which has created potentially unnecessary conflict for the 

 Commission. 



A more positive atmosphere would exist if congress had not 

 embellished the straight forward charge of preventing future 

 impairment. 



The analytical techniques being developed by the 

 Commission's committees will be used to analyze a candidate set 

 of emission management options that have been approved by the 

 Commission for in depth analysis. These options are: 



• A baseline option that includes mandatory requirements 

 in the Clean Air Act and other federal, state and local programs. 



• A straight technological approach where sources would 

 have prescribed control parameters . The concept of controls 

 could include fuel and management practice requirements. 



• A standard or visibility goal approach similar to the 

 current state implementation plan process. In this approach 

 standards or goals for parks and wilderness areas would be 

 established and states or source regions would be required to 

 reduce emissions proportionate to there contribution to any 

 exceedences of the standard. 



• An emission cap approach with the option of utilizing a 

 market based approach to achieve and stay within caps. Caps 

 could be either fixed or decreasing over time and trading could 

 be indexed to visibility improvement. International trading may 

 be a possibility if Mexican emissions are found to be a 

 significant haze contributor. 



Incorporated into each of these options will be scenarios 

 that include such components as incentives, voluntary programs, 



