Interested and affected persons may file comments by Aug. 10 with the Public Utilities Commission of Nevada (PUCN) on a Southern California Edison (SCE) petition involving a transmission tower of the Eldorado–Mohave 500-kV line, according to a July 18 PUCN notice.
As noted in the petition, SCE is requesting an advisory opinion or a declaratory order as to whether a proposed replacement transmission tower constitutes a “like facility” for the purposes of Nevada Revised Statutes (NRS) 704.865(1).
SCE, which is a co-owner and operator of the Eldorado substation in Boulder City, Nev., as well as the Eldorado–Moenkopi and Eldorado–Mohave transmission lines, intends to modify its transmission lines by crossing the Eldorado–Moenkopi line and the Eldorado–Mohave line.
The purpose of the project is to comply with Western Electrical Coordinating Council (WECC) performance criteria that applies to adjacent transmission lines. The criteria requires a corrective action plan designed to reduce the likelihood, or mitigate the consequences and adverse impacts, of a common mode failure, the petition added.
The transmission corridor south of the Eldorado substation is occupied by three transmission lines within the same right of way (ROW) for about eight miles: the Eldorado–Lugo 500-kV line, the Eldorado–Mohave line and the Eldorado–Moenkopi line – in order, from west to east.
Studies indicate that the common mode failure of the adjacent transmission circuits, Eldorado–Lugo and Eldorado–Mohave, will cause overloads on the Lugo–Victorville line, the petition added.
Swapping transmission line positions between the Eldorado–Mohave and the Eldorado–Moenkopi lines would reconfigure the corridor in a way that the Eldorado–Lugo and the Eldorado–Mohave lines would no longer be defined as adjacent transmission circuits, thus, achieving the project objective, the petition said.
The California ISO (Cal-ISO) has approved the project as a “policy-driven” project, the petition said.
The proposed line swap involves the replacement of existing transmission facilities and installation of a new transmission tower, the petition said, adding that with the exception of one of the replacement transmission towers, identified as M49-T5, all of the affected facilities are located within the corporate boundaries of Boulder City, and, as such, do not require a Utility Environmental Protection Act permit to build under NRS 704.860(2).
The part of the project located outside the corporate limits of Boulder City involves replacement of a transmission tower with a taller transmission tower. The line swap, the petition added, requires that the height of the M49-T5 transmission tower be increased from 94 feet to 182 feet.
SCE believes that replacement of a transmission tower with a taller transmission tower represents “replacement of an existing facility with a like facility” and “does not constitute construction of a utility facility” under NRS 704.865(1), according to the petition.
Accordingly, SCE requests that the PUCN issue an advisory opinion or a declaratory order finding that, for the purposes of NRS 704.865(1), the proposed replacement transmission tower represents a “like facility” to the transmission tower being replaced, the petition said.
Among other things, the petition noted that the increase in height is immaterial because, due to the tower’s location well outside of a populated area, the tower not being in proximity to an airport, and the tower being lower than 200 feet, it does not obstruct anyone’s view or require a determination of no hazard from the Federal Aviation Administration.