ARCHIVED REPORTS LEC APPLICATION FOR CERTIFICATION

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SECTION 3.0:ELECTRIC TRANSMISSION to move directly into the Interconnection System Impact Study (ISIS) phase. To further expedite the study,NCPA, CAISO and PG&E have agreed to include elements from the ISIS into the Interconnection Facilities Study (IFAS). The draft IFAS will be completed by PG&E and CAISO and delivered to NCPA by December 2008. A copy of the draft IFAS will be provided to the California Energy Commission at that time. 3.4 Transmission Line Safety and Nuisances This section discusses safety and nuisance issues associated with the proposed electrical interconnection of the LEC. 3.4.1 Electrical Clearances Typical high-voltage overhead transmission lines are composed of bare conductors connected to supporting structures by means of porcelain, glass, or plastic insulators. The air surrounding the energized conductor acts as the insulating medium. Maintaining sufficient clearances, or air space, around the conductors to protect the public and utility workers is paramount to the safe operation of the line. The required safety clearance required for the conductors is determined by considering factors such as the normal operating voltages,conductor temperatures, short-term abnormal voltages,wind-blown swinging conductors,contamination of the insulators,clearances for workers, and clearances for public safety. Minimum clearances are specified in the NESC (IEEE C2) and CPUC General Order 95 (GO 95). Electric utilities, state regulators,and local ordinances may specify additional (more restrictive) clearances. Typically,clearances are specified for the following: • Distance between the energized conductors themselves • Distance between the energized conductors and the supporting structure • Distance between the energized conductors and other power or communication wires on the same supporting structure, or between other power or communication wires above or below the conductors • Distance from the energized conductors to the ground and features such as roadways, railroads, driveways,parking lots,navigable waterways,and airports • Distance from the energized conductors to buildings and signs • Distance from the energized conductors to other parallel power lines The transmission interconnection for the LEC will be designed to meet appropriate national, state, and local clearance requirements. 3-2 SAC/371322/082350006(LEC_3.0_ELECTRANS.DOC)