This statement, one of a series prepared by the U.S. Department of Energy’s Bonneville Power Administration on various facets of its construction and maintenance activities, addresses the potential impact of a major new facility proposed for fiscal year 1979. To allow power generated in Wyoming to be delivered to Southwest Oregon and to facilitate the exchange of electric power between the Pacific Northwest and the Middle Snake region, two basic plans of service, each with two corridor routing options, have been identified to meet system requirements. BPA proposes construction of the following two transmission facilities: (1) a 500-kV line from Idaho Power Company's Brownlee Substation in Idaho to BPA's Slatt Substation near Arlington, Oregon, and (2) a 500-kV line from Buckley (near Maupin, Oregon) to Malin, Oregon. This statement must be reviewed and used in conjunction with the overall programmatic environmental statement titled "The Role of the Bonneville Power Administration in the Pacific Northwest Power Supply System, Including Its Participation in the Hydro-Thermal Power Program: A Program Environmental Statement and Planning Report" (The "Role EIS"), particularly Appendix B - BPA Power Transmission.