In July 2007, Idaho Power Company (IPC) and Great Basin Transmission LLC (Great Basin) submitted to the Bureau of Land Management (BLM) an SF-299 seeking approval of an amendment to Right-of-Way (ROW) Grant NVN-49781. The BLM had granted the ROW, which approved construction of the Southwest Intertie Project (SWIP) 500kV transmission line, to IPC in 1994. IPC had subsequently put the project on hold until it entered into an agreement with Great Basin to go forward with the project.
The amendment accommodated two modifications for the southern portion of the SWIP. In May, 2008, IPC requested that the BLM assign it's interest in the southern portion of the SWIP ROW to Great Basin. The assignment was approved under Right of Way Grants NVN-85210 and NVN-85211.
The two proposed modifications consist of (1) an extension of the ROW and 500kV transmission line for approximately 4 miles from the originally approved southern terminus, which was to be at the Dry Lake 500kV Substation (which was never constructed), to the now existing Harry Allen 500kV Substation in Clark County, Nevada, and (2) a modification of the ROW Grant in the Robinson Summit area northwest of Ely in White Pine County, Nevada, which would shift the location of the Robinson Summit Substation from its currently approved location, to a new site, referred to as Thirtymile Substation immediately to the west of the designated SWIP utility corridor, and approximately ¾ mile to the northwest of the currently approved site.
In August 2007, an Environmental Assessment (EA) was prepared and distributed by the BLM to the public and agencies for review. Included in this EA were an evaluation of these two modifications as well as an evaluation of a relocated portion of the SWIP ROW to the west side of U.S. Highway 93 in Coyote Spring Valley which had been mandated by Congress in the 2004 Lincoln County Conservation, Recreation, and Development Act (LCCRDA). Additionally, the EA also addressed policy and resource updates associated with key environmental resources that may affect the SWIP.
The Decision Record and Finding of No Significant Impact were signed July 30, 2008. Great Basin has submitted a Construction, Operations and Maintenance Plan for the BLM to review prior to issuing a Notice to Proceed for the project.