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SECTION 6.0:ALTERNATIVES 6.5.1 Alternative Natural Gas Supply Pipeline Routes The preferred natural gas pipeline route would be adjacent to the existing 2.5-mile pipeline for the STIG Plant which is adjacent to the proposed LEC site. The existing gas pipeline exits the STIG plant approximately 400 ft to the south of the White Sough metering station and then turns east along the access road to the WPCF and under Interstate 5 (1-5). The pipeline continues east from I-5, along a utility easement,bordering several private agricultural fields until the intersection of De Vries Road and Armstrong Road. The pipeline then continues in an easement adjacent to the north side Armstrong Road to PG&E's high pressure natural gas pipeline#108. Due to the presence of the existing 2.5-mile gas pipeline, no other alternatives were analyzed. 6.5.2 Electrical Transmission System Alternatives The preferred transmission route would be to link the LEC site to the power grid through the existing STIG plant's 230-kV switchyard substation by a three-phase 230-kV transmission circuit. The proposed 230-kV route will exit the project site at the northwest corner and will extend along the northern border of the STIG plant before turning south along the eastern boundary of the STIG plant and continuing to the existing 230-kV switchyard.From the switchyard,the line will tie into the PG&E 230 kV transmission corridor. Due to the presence of the existing electrical switchyard adjacent to the LEC site, no other alternatives were analyzed. 6.5.3 Water Supply Alternatives The LEC project will connect with the WPCF for supplies of recycled water for cooling through a utility corridor linking the power plant and WPCF. Other sources of cooling water might include potable water from an onsite well used to supply potable water to LEC, or the potable water from the WPCF onsite well. Reclaimed water is clearly the better alternative because it provides for beneficial use for treated wastewater which might otherwise be wasted. Using potable water from the onsite well would involve consuming large quantities of scarce fresh water for power plant cooling that could be more beneficially used for other purposes. 6.6 Technology Alternatives The configuration of the LEC was selected from a wide array of technology alternatives. These include generation technology alternatives,fuel technology alternatives,combustion turbine alternatives,NOX control alternatives. 6.6.1 Generation Technology Alternatives Selection of the power generation technology focused on those technologies that can utilize the natural gas readily available from the existing transmission system. Following is a discussion of the suitability of such technologies for application to the LEC. 6.6.1.1 Conventional Boiler and Steam Turbine This technology burns fuel in the furnace of a conventional boiler to create steam. The steam is used to drive a steam turbine-generator,and the steam is then condensed and returned to 6-14 SAC/371322/082330003(LEC_6.0_ALTERNATIVES.DOC)