3. Procedural Requirements under Rule 16.4

Rule 16.4 governs the process for the filing and consideration of Petitions for Modification. Rule 16.4(b) requires that a Petition for Modification concisely state the justification for the proposed relief and to propose specific wording for all requested modifications. SCE's Petitions contained a concise but thorough statement of justification for the proposed modifications. SCE's Response proposed specific wording for all requested modifications in Appendices A and B of that Response. Hence, this requirement has been fulfilled for the Petitions.

Rule 16.4(d) states that if more than one year has elapsed since the effective date of the decision, then a petition for modification must explain why it could not have been presented within one year of the effective date of the decision. SCE's Petitions are based upon a number of factors, including changes to costs over time and engineering costs that were uncertain until third-party interconnection requests were filed and designs could be completed. Most significantly, given a significant increase in interconnection requests, SCE has elected to upgrade ATP Segments 1, 2, and 3 from 230 kV to 500 kV operability, as permitted in the Decisions. Those Decisions, however, did not include some of the costs of this upgrade in their approved maximum costs because such a system upgrade was not anticipated to occur until much later. Given these factors, which were known at the time of the Decisions, we anticipated that such Petitions would be necessary and explicitly authorized their filing in Ordering Paragraph 6 of both Decisions. While it is possible that some portions of the requested relief could have been presented at an earlier date, the benefits of considering them in a consolidated manner, rather than piecemeal, justify the delay.

Hence, we conclude that SCE's Petitions, viewed together with SCE's Response, comply with the requirements of Rule 16.4.