Kirkwood Meadows Public Utilities District Power Line Reliability Project Project Description: Alternatives, Including the Proposed Action KMPUD Project Description page 1 of 31 Introduction ____________________________________________ This chapter describes and compares the alternatives considered for the Kirkwood Meadows Power Line Reliability Project. It describes both alternatives considered in detail and those eliminated from detailed study. The end of this chapter presents the alternatives in tabular format so that the alternatives and their environmental impacts can be readily compared. Alternatives Considered in Detail __________________________ Based on the issues identified through public comment on the proposed action, the Forest Service developed four (4) alternative proposals that achieve the purpose and need differently than the proposed action. In addition, the Forest Service is required to analyze a No Action alternative. The proposed action, alternatives, and no action alternative are described in detail below. Alternative 1 – No Action Under the No Action alternative, current management plans would continue to guide management of the project area. No power line or supporting structures would be constructed to accomplish the purpose and need, and the Kirkwood community and ski resort would continue to be powered primarily by diesel generated electricity. Currently low sulfur dyed diesel fuel #2 is trucked into Kirkwood roughly two to three times per week during the winter months and once per week during the summer months. The number of trips depends on the consumption. Snowmaking, for instance, may consume as much as 5,000 gallons in a 24-hour period. There have been fuel spills during transport and transfer of fuel to the storage tanks. Alternative 2 – Proposed Action The Proposed Action would involve the construction of a 34.5 kV power line connecting Kirkwood (in Alpine, Amador, and El Dorado counties) to an existing 115 kV transmission line owned by Pacific Gas & Electric Company (PG&E) that terminates at the PG&E hydroelectric facility at Salt Springs Reservoir in Amador County. The Proposed Action would extend the existing 115 kV as an overbuild circuit along the existing 12.5 kV overhead line for 1.3 miles to a new substation located near the intersection of the overhead line with Cole Creek Road. At the new substation, named KM Green Substation, the voltage of the overbuild circuit would be stepped down from 115 kV to 34.5 kV and continue to Bear River Road along the remaining 1.8 miles of PG&E overhead power line. The existing overhead power line terminates on the north side of Bear River Road. From Bear River Reservoir, the proposed 34.5 kV power line would be buried within existing roadways and disturbance corridors the remaining 24.6 miles to Kirkwood, KMPUD Project Description page 2 of 31 California. No new overhead power lines would be constructed except within the existing corridor. At Kirkwood, the 34.5kV line would terminate at a new substation named KM Blue. Supporting Structures In addition to the 34.5 kV overhead and underground power line segments, the Proposed Action requires the construction of several supporting facilities, including: • KM Green Substation: A KMPUD Interconnection substation located at the terminus of the 115 kV line, • KM Blue Substation: A KMPUD substation located at Kirkwood, • Sectionalizing cabinets located approximately every 2,600 to 3,500 feet along the underground cable alignment, and • Shunt reactors • Fiber Optic Line KM Green Substation: 115kV to 34.5kV step down The purpose of this substation is to connect Kirkwood Meadows PUD to the PG&E high voltage electrical grid and to step down the voltage from 115 kV to 34.5 kV. The existing 115 kV line would be extended from its current termination at Salt Springs Hydroelectric Powerhouse through an overbuild of the existing 12.5 kV line to the new substation. The location of the KM Green substation will be selected based on site access, suitability for construction, and minimization of impacts to resources. The substation will be located as close as possible to the existing 12.5 kV overhead lines along Segment 2, but outside of the FERC boundary (100 feet wide on either side of the existing powerline) and south of Forest Service Road 8N03. Within this area, site selection will be based on accessibility from existing roadways, visual quality, slope, geology, vegetation, and distance from riparian conservation areas and other sensitive habitats. A minimum distance of 300 feet from intermittent or perennial streams and 100 feet from ephemeral streams will be maintained. The entire area being analyzed for selection is located within a Partial Retention VQO designation. The KM Green Substation would include a 35-foot high, steel A-frame structure upon which the 115kV conductors will terminate, a 115kV circuit breaker and disconnect switch, instrument transformers for metering, a power transformer that would transform the voltage from 115 kV to 34.5 kV, and a 34.5 kV circuit breaker and two associated disconnect switches. The 34.5 kV transmission line would leave the substation from a steel structure with an approximate height of 30 feet. There will be a small building (approximately 15’ x 15’ x 12’) to house the protective relays, communications and control equipment, and a battery. Buried beneath the substation would be a ground grid made up of copper cables buried 18” below finished grade. The surface of the substation would be approximately six inches of crushed rock. The substation would be KMPUD Project Description page 3 of 31 surrounded by a 16-foot high chain link fence with three strands of barbed wire at the top. The fence will enclose an area of approximately 150’ x 100’. For safety purposes, the ground grid will extend three feet outside of the fence (figure). The KM Green Substation would be visually screened from roadways through the strategic planting of native trees and shrubs, and using a coated and darkened fence to reduce shine. KM Blue Substation at Kirkwood The KM Blue Substation serves as the termination point of the 34.5 kV line. The substation will transform the electrical voltage from 34.5 kV to 12.5 kV. This is necessary for distribution of power to KMPUD’s loads with an interconnection to existing generation. The substation would be located adjacent to the new KMPUD powerhouse in the upper Red Cliff parking lot. The location was selected based on its proximity to the previous powerhouse and accessibility to the existing electrical distribution infrastructure. The KM Blue Substation would be composed of a termination structure for the 34.5kV insulated cables, instrument transformers at 34.5 kV and 12.5 kV, a 34.5 kV circuit breaker and two associated disconnect switches, a power transformer that will transform the voltage from 34.5 kV to 12.5 kV, and 12.5 kV distribution equipment in the form of circuit breakers and disconnect switches housed in a metal-clad switchgear building. All 12.5 kV distribution feeders will leave the substation through underground cables. The metal-clad switchgear building will also house the protective relays, communications and control equipment, and a battery. Buried beneath the substation will be a ground grid made of copper cables buried 18” below finished grade. The surface of the substation will be approximately six inches of crushed rock. The substation will be surrounded by a 16-foot tall chain link fence with three strands of barbed wire at the top. The fence will enclose an area of approximately 100’ X 100’. For safety purposes the ground grid will extend three feet outside of the fence. Sectionalizing Cabinets Sectionalizing cabinets are used to join segments of the power line together and to aid in the maintenance and repair of the system. The sectionalizing cabinets would be 1’10” wide by 7’ long, approximately 2’6” high. A 1’-6” ground sleeve pad would be buried below grade. The sectionalizing cabinets would be installed at transition points between direct burial segments and segments where the power line is placed within conduit. “Warning” signs would be mounted on the outside face of the secured access door. A “Danger” sign would be mounted on the inside face of the access door. Along power line, sectionalizing cabinets would be spaced approximately every 2,600-feet in single conduit installation sections and spaced every 3,400 feet in direct burial installation. The location of sectionalizing cabinets will be determined during preparation of detailed design in KMPUD Project Description page 4 of 31 consideration of the local engineering, environmental, visual, and safety constraints, and then field fit to select the most optimal location. Sectionalizing cabinets are necessary at transition points between conduit and direct burial sections; however, the sections in conduit will be extended away from scenic corridors in order to place the sectionalizing cabinets in areas less visible and away from traffic. To the extent possible, sectionalizing cabinets will be: • Located outside of the Caltrans right of way; • Located in areas accessible from existing roadways; • Visually screened from Highway 88, Bear River Road (FS Road 8N03) and other recreational use areas. Shunt Reactors Shunt reactors would be necessary along the alignment to regulate voltage through the countering of electrical capacitance. Shunt reactors would be located as determined during detailed design. The shunt reactors would be installed within a metal cabinet approximate 15 feet x 15 feet with a height of 4.5 feet. Based on final system design and configuration of the KMPUD powerhouse and substation, approximately 2 to 5 shunt reactors will be necessary. One shunt reactor will be located at the KM Blue substation. The other shunt reactors, if necessary, will be spaced intermittently along the power line. Location criteria for the shunt reactors is the same as for sectionalizing cabinets.