CHAPTER IV WORKPAPER SUMMARY Transmission Pipeline Enhancement Plan

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1 SUMMARY Transmission Pipeline Enhancement Plan SoCalGas Workpaper Workpaper Testimony Section Corresponding Testimony Tables Workpaper Page Phase 1A Pipeline Miles and Subprioritization IV.D.1 and IV.D.4 IV 5 WP IV 2 SDG&E Workpaper 1 Workpaper Testimony Section Corresponding Testimony Tables Workpaper Page Phase 1A Pipeline Miles and Subprioritization IV.D.1 and IV.D.4 IV 5 WP IV Line 1600 cannot be hydrotested until a replacement line is constructed. Line 1600 is planned to be In Line Inspected using Transverse Flux Inspection (TFI) Technology in Phase 1A, and planned to be replaced in Phase 1B. Table IV 5 does not include Line1600 becausethereplacement will not becompleted until Phase1B. WP IV 1 of 12

2 Transmission Pipeline Enhancement Plan Page 2 of 12 Description and Methodology SoCalGas prioritized the pressure test or replacement of transmisison pipelines in Phase 1A ( ) to be pipelines or pipeline segments in Class 3 or 4 locations or Class 1 or 2 high concequence areas without sufficient documentation of post construction pressure tests to at least 1.25 times their maximum allowable operating pressure. Per the decision tree (Figure IV 1), these pipelines were arranged into one of five groups based upon the pipeline length, impacts to customers, and capability to be in line inspected. The pipelines within each group were then sub prioritized for project initiation purposes by the pipeline's potential impact radius (PIR) divided by a long seam factor. A pipeline's potential impact radius is calulated by squaring the diameter (inches) of the pipe and multiplying this value by the pipeline's MAOP (psig). The square root of this product is then multiplied by the constant 0.69 to provide the radius in feet. The fomula is PIR = 0.69*square root of (MAOP*Diameter 2 ). The long seam factor is identified in 49 CFR While these subprioritizations will be used to initiate projects, it is anticipated that many projects will be addressed in parallel to complete all Phase 1A work within the 4 year window. Also, any segments or lengths of pipeline that will be included outside the respective groups and this program are identified as "accelerated" lengths and are tabulated below in miles. Phase 1A Subprioritization Groups 1 through 5 In support of the cost estimation process each Phase 1A pipeline was placed into one of five groups. The first group includes all test or replacement segments that were 1,000 feet or less in length. The second group includes pipelines that cannot be taken out of service for pressure testing due to non manageable customer impact and are not piggable. Pipelines in the second group are planned for replacement in Phase 1A. The third group includes pipelines that are piggable but cannot be taken out of service for pressure testing due to nonmanageable customer impact. Any pipeline in this group that cannot be replaced within the Phase 1A time period is planned for in line inspection in Phase 1A with the replacement to be completed in Phase 1B (Box 6 in the decision tree). The fourth group of pipelines can be taken out of service, are not piggable, and are planned to be pressure tested in Phase 1A. The fifth group of pipelines can be taken out of service, are piggable, and are planned to be both in line inspected and pressure tested in Phase 1A. WP IV 2 of 12

3 Transmission Pipeline Enhancement Plan Page 3 of 12 The tables below summarizes the Phase 1 groups and pipeline subprioritization. Complete Direct Examination or Replace and Abandon Group 1 (Box 1)(1,000 feet or less criteria miles) ID805 T XO BO BR XO LT XO BO BR A B LT1BP BP BP2ST ID BR BR BR BR WP IV 3 of 12

4 Transmission Pipeline Enhancement Plan Page 4 of U X BR BP BP BP ST ID629 T BO BR N ID ID BO BR F BP KST C A ID465 T ID465 T LT J WP IV 4 of 12

5 Transmission Pipeline Enhancement Plan Page 5 of A FST BP2ST BP2ST BP2ST BP ID502 T ID567 P ST Total Group WP IV 5 of 12

6 Transmission Pipeline Enhancement Plan Page 6 of 12 Replace and Abandon Sub Group 2 (Box 2) North A K F A A A WP IV 6 of 12

7 Transmission Pipeline Enhancement Plan Page 7 of A F I BR A A Total Group WP IV 7 of 12

8 Transmission Pipeline Enhancement Plan Page 8 of 12 In line Inspect (TFI) and Replace Group 3 (Box 3) Total Group (none planned at SoCalGas) Total Group 2 + Group 3 Criteria Miles Accelerated Miles Pressure Test Group 4 (Box 4) 1 Playa del Rey La Goleta Honor Rancho Total Group WP IV 8 of 12

9 Transmission Pipeline Enhancement Plan Page 9 of 12 In line Inspect (TFI) and Pressure Test Group 5 (Box 5) East West East West East Total Group Total Group 4 + Group 5 Criteria Miles Accelerated Miles WP IV 9 of 12

10 SDG&E Phase 1A Pipeline Miles and Subprioritization Chapter IV WORKPAPER Transmission Pipeline Enhancement Plan Page 10 of 12 Description and Methodology SDG&E prioritized the pressure test or replacement of transmisison pipelines in Phase 1A ( ) to be pipelines or pipeline segments in Class 3 or 4 locations or Class 1 or 2 high concequence areas without sufficient documentation of post construction pressure tests to at least 1.25 times their maximum allowable operating pressure. Per the decision tree (Figure IV 1), these pipelines were arranged into one of five groups based upon the pipeline length, impacts to customers, and capability to be in line inspected. The pipelines within each group were then sub prioritized for project initiation purposes by the pipeline's potential impact radius (PIR) divided by a long seam factor. A pipeline's potential impact radius is calulated by squaring the diameter (inches) of the pipe and multiplying this value by the pipeline's MAOP (psig). The square root of this product is then multiplied by the constant 0.69 to provide the radius in feet. The fomula is PIR = 0.69*square root of (MAOP*Diameter 2 ). The long seam factor is identified in 49 CFR Although these subprioritizations will be used to initiate projects, it is anticipated that many projects will be addressed in parallel to complete all Phase 1A work within the 4 year window. Also, any segments or lengths of pipeline that will be included outside the respective groups and this program are identified as "accelerated" lengths and are tabulated below in miles. Phase 1A Subprioritization Groups 1 through 5 In support of the cost estimating process, each Phase 1A pipeline was placed into one of five groups. The first group includes all test or replacement segments that measure 1,000 feet or less in length. The second group includes pipelines that cannot be taken out of service for pressure testing due to non managable customer impact and are not piggable. Pipelines in the second group are planned for replacement in Phase 1A. The third group includes pipelines that are piggable but cannot be taken out of service for pressure testing due to non managable customer impact. Any pipeline in this group that cannot be replaced within the Phase 1A time period is planned for in line inspection during Phase 1A with the replacement to be completed under Phase 1B (Box 6 in the decision tree). The fourth group of pipelines can be taken out of service, are not piggable, and are planned to be pressure tested in Phase 1A. The fifth group of pipelines can be taken out of service, are piggable, and are planned to be both in line inspected and pressure tested in Phase 1A. WP IV 10 of 12

11 SDG&E Phase 1A Pipeline Miles and Subprioritization Chapter IV WORKPAPER Transmission Pipeline Enhancement Plan Page 11 of 12 The tables below summarizes the Phase 1 groups and pipeline subprioritization. Complete Direct Examination or Replace and Abandon Group 1 (Box 1)(1,000 feet or less criteria miles) Total Group Replace and Abandon Group 2 (Box 2) Total Group In line Inspect (TFI Phase 1A) and Replace (Phase 1B) Group 3 (Box 3)(Replacement in Box 6) Total Group Total Group 2 + Group 3 (1) Criteria Miles Accelerated Miles (1) Line 1600 cannot be hydrotested until a replacement line is constructed. Line 1600 is planned to be In Line Inspected using Transverse Flux Inspection (TFI) Technology in Phase 1A, and planned to be replaced in Phase 1B. Table IV 5 does not include Line 1600 because the replacement will not be completed until Phase 1B. WP IV 11 of 12

12 SDG&E Phase 1A Pipeline Miles and Subprioritization Chapter IV WORKPAPER Transmission Pipeline Enhancement Plan Page 12 of 12 Pressure Test Group 4 (Box 4) Total Group In line Inspect (TFI) and Pressure Test Group 5 (Box 5) Total Group (none planned at SDG&E) Total Group 4 + Group 5 Criteria Miles Accelerated Miles WP IV 12 of 12