Why may a state choose to submit an abbreviated CAIR SIP revision?
A state choosing to adopt one or more of the part 96 CAIR model trading rules (the SO2, NOx annual, or NOx ozone season model trading rule) to address its CAIR requirements may save time and resources by avoiding development of full SIP revisions and still be able to make certain key implementation decisions (e.g., regarding the methodology for allocating NOx allowances) through the use of abbreviated SIP revisions. Note that EPA is the implementing authority under a FIP whether or not that FIP trading program is modified by an abbreviated SIP revision. The abbreviated SIP option may also be attractive to a state that chooses to do a full CAIR SIP revision but may not be able to meet the submission deadline. If the state submits both a full SIP revision after its deadline and an abbreviated SIP revision on or before its deadline EPA may be able to approve the timely abbreviated SIP revision, but not the late full SIP submission, in time for the 2009 compliance year. The state’s full SI
