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Of A A E k I a 6 Y 1 1 * F RIVERSIDE PUBLIC UTILITIES Board Memorandum F U R L II C U 7 1 L I T I E S BOARD OF PUBLIC UTILITIES DATE: December 2, 2011 ITEM NO: 3 SUBJECT: MT. VIEW SEISMIC UPGRADE—WORK ORDER NO. 1112103 ISSUE: Board of Public Utilities approval is requested for Work Order No.1112103. RECOMMENDATION: That the Board of Public Utilities approve Work Order No. 1112103 in the amount of$309,105 for seismic upgrades at Mt. View Substation. BACKGROUND: Mt. View Substation was originally designed and built in the 1960's. The Substation's main overhead structural assembly is a steel box-type structure consisting of four bays with an overall footprint of 50 feet wide by 55 feet long. In general, substation structures are designed to support various pieces of high voltage electrical apparatus (such as disconnect switches, insulators, bus, cable, lightning arrestors, etc.). During an earthquake,these substation structures, including their associated foundations and anchor bolts, must withstand seismic loading while supporting the weight of the electrical equipment that is attached. Recently,SAIC Energy,Environment& Infrastructure, LLC(SAIC)was retained to conduct a seismic analysis of the substation structures, including associated foundation and anchor bolts at the Mt. View Substation. The Board of Public Utilities approved a similar project for seismic upgrades at La Colina and Hunter Substations on April 1, 2011. As part of the seismic analysis of the Mt.View Substation, SAIC modeled the main support structures using a structural computer program. The structural computer program was used to analyze substation structure by simulating ground movement for an earthquake which applied both lateral and vertical seismic loads to the substation structure,foundations, and anchor bolts. The results of the seismic analysis concluded that various parts of the substation structure, including associated foundations and anchor bolts do not meet current seismic standards. In order for Mt.View Substation to safely withstand seismic events,the structure and foundations for Mt.View Substation will require some modifications. These seismic upgrades include the replacement of existing structural beams and the reinforcement of existing foundations. Based on the results of the seismic analysis by SAIC, staff recommends that the seismic upgrades at Mt. View Substation be completed. If approved, the work to install the seismic upgrades is expected to be completed June 2012. Outages to support this work will, if required, be coordinated so as to not affect service to Utility customers. FISCAL IMPACT The total capital expenditure for this project on Work Order No. 1112103 is estimated to be$309,105 which includes all costs for consultant analysis, design, engineering, rental equipment, materials, construction, overhead, and contingency. 1