2.1 Overview of the Proposed Project - Keystone XL pipeline - US ...

Draft Supplemental Environmental Impact StatementKeystone XL ProjectElectrical Cooperative’s service to Pump Station 13. Land acquisition for the substationexpansion would be completed by Western.• Philip Substation, Haakon County, South Dakota: Western’s Phillip Substation would requirean expansion with a new 115-kV bay addition and two 20 MVAR capacitor banks. Theexpansion would accommodate West Central Electric Cooperative’s service to Pump Station18. A slight yard expansion onto property already owned by Western accommodated a new230-kV breaker addition unrelated to the proposed Project, and provided enough room toinstall the new Central Electric Cooperatives facilities. No additional land acquisition wouldbe required.• Midland Substation, Haakon County, South Dakota: Western’s existing Midland Substationwould require expansion for a new 115-kV bay to accommodate West Central ElectricCooperatives service to Pump Station19. Construction of this interconnection would require asmall yard expansion to the east. Land acquisition for the substation expansion would becompleted by Western.• Gregory Substation, Gregory County, South Dakota: Western would expand its GregorySubstation with a new 115kV switchyard adjacent to the existing and aging facilities. Inorder to accommodate Rosebud Electric Cooperative’s request for serving Pump Station 2,Western would be required to construct a new six-position main-and-transfer sub, includingeight 15-kV power circuit breakers, two 10 MVAR capacitor banks, and take-off structures,reposition the existing 115/12.47 power transformer, and install new control buildingcontrols and relays. Land acquisition for the substation expansion would be completed byWestern.Locations of four of the five new pump stations in Nebraska have not yet been finalized, and thedetails regarding the distribution lines have not yet been determined. It is expected that the sitingand construction of these lines would be similar to those in Montana and South Dakota.In each of the states, the pump stations would have a substation integrated into the general pumpstation layout. The exact location of each substation cannot be identified at this time because theelectrical supply lines would access pump stations from different alignments. Each substationfootprint would be approximately 1 to 1.5 acres and is included in the total land size of eachpump station. The actual size of a substation would be dictated by the specific design and sizerequirements of the local power supply company, the capacity of the power supply linesconnected to each specific pump station, and the associated equipment. Figures 2.1.4-1 and2.1.9-1 provide typical layouts for substations and pump stations.Other electrical power requirements, such as power for MLVs, would be supplied fromdistribution service drops from adjacent distribution power lines with voltage below 69 kV. Eachdistribution service drop would typically be less than 200 feet long, and would require theinstallation of one or two poles and a transformer. The electric utility would typically install apole-mounted transformer within 200 feet of the valve site location. However, in some cases theelectric utility would install the transformer on an existing pole, which would be more than 200feet from the valve site. The decision on where the transformer pole would be located wouldgenerally be based on the most economical installation. For example, MLVs north of the MilkRiver in Montana would be supplied from transformers on poles along small lines that currentlysupply power to irrigation systems. Upon completion of the new service drops, the electricalpower providers would restore the work area as required, in accordance with local permits.Project Description 2.1-84 March 2013