Virginia State Corporation Commission (SCC) on Nov. 15 said that FirstEnergy’s (NYSE:FE) Potomac Edison has reasonably demonstrated that a proposed project to rebuild the 138-kV Double Toll Gate-Riverton transmission line in Clarke and Warren counties in Virginia is needed, and that the project reasonably minimizes impact to environmental, scenic and historic resources.
“Staff therefore does not oppose issuing the [company’s] requested certificate of public convenience and necessity,” staff said in a report filed with the SCC.
As noted in the report, the project involves replacing the conductor on about 6.3 of 7.1 miles of the line, replacing 52 out of 60 structures along the line with substantially similar ones, and minor upgrades to the company’s Double Toll Gate and Riverton substations, all within existing right of way (ROW).
The new structures would be on average about five feet higher to accommodate the sag associated with the new conductors, staff said, adding that according to the company, the maximum height of the replacement structures would be 90 feet, with a maximum increase in height of 15 feet. Some structures would be decreased in height.
The requested in-service date is June 1, 2017, and the company plans to begin construction in January 2017 if the project receives all necessary approvals, staff added. The company estimates a cost of about $6.1m for work on the transmission line, and $41,000 for the associated substation work.
Staff also said that it verified the company’s power flow studies and found that the thermal violations identified by Potomac Edison are valid and support the need for the project. Staff also said that while the project area crosses or nears some residences, scenic assets, historic districts, natural resources, and recreational areas, the use of existing ROW and replacement of structures with similar kind and location should result in minimal or negligible incremental impact.
The company said that power flow studies indicate certain NERC Category P6 contingencies will result in thermal violations on the line as of June 1, 2017. Specifically, staff added, the sequential loss of two 115-kV or 138-kV transmission lines or transformers in the area would force additional load onto the Double Toll Gate-Riverton line, leading to a thermal overload of 1.6-7.6%.
Among other things, staff said that the project was identified in the 2012 PJM Interconnection Regional Transmission Expansion Plan as baseline project no. b2268, needed to resolve a system reliability problem.
As TransmissionHub reported, the Virginia Department of Environmental Quality (DEQ) on Sept. 27 issued recommendations for the proposed project, including that the company conduct an on-site delineation of wetlands and streams within the project area with verification by the U.S. Army Corps of Engineers.
Regarding wildlife resources and protected species, for instance, the DEQ report noted that the state Department of Game and Inland Fisheries (DGIF) documents the federally listed threatened Madison Cave isopod and the state-listed threatened Wood turtle from the project area. However, based on the project scope and location, the DGIF does not anticipate the project to result in adverse impacts upon the Wood turtle.