Virginia State Corporation Commission (SCC) staff has recommended that the SCC approve Appalachian Power Company’s (APCo) proposed project that includes two 138-kV overhead transmission lines within Wythe County, Va., and the town of Wytheville, Va.
“The staff believes that the company has demonstrated a public need for the proposed project,” staff said in March 18 pre-filed testimony on the company’s application for a certificate of public convenience and necessity (CPCN), which was filed with the SCC in November 2012.
The project is consistent with existing and future land use plans, and the Virginia Department of Environmental Quality (DEQ) has provided its recommendations for minimizing potential environmental impacts. “Based on its investigation, the staff recommends that the commission approve the proposed project and issue the requestedCPCN,” staff said.
A hearing is scheduled for April 16.
The company, which is a unit of American Electric Power (NYSE:AEP),is seeking approval and issuance of a CPCN to build and operate the two lines, and provided two possible routes for the lines, including its preferred route of about 17.6 miles and a possible alternative route of about 20.1 miles. Staff also said the preferred and viable alternative routes would allow the project to be built and operated effectively and efficiently as a satisfactory solution for the projected voltage criteria violations and existing operational problems.
The preferred route includes about 12.5 miles of double-circuit and about 5.1 miles of single-circuit transmission line.
Staff also said that the company proposes a 100-foot right-of-way (ROW), supporting structures and conductors and substation improvements. Additionally, APCoseeks approval of a 500-foot-wide corridor based generally on the centerline of its preferred route.
The project is meant to improve service reliability and support projected load growth in the Wythe area. Staff also noted that the company wants the estimated $100m project to be in service on Dec. 31, 2015.
According to APCo, a voltage issue was identified on the AEP 138-kV transmission system in the 2011 regional transmission expansion planning study conducted by PJM Interconnection on behalf of APCo. The PJM board has approved the project.
Staff added that among other concerns, APCo has predicted that during projected summer 2015 peak load conditions, the N-1-1 double contingency outage most adverse to the Wytheville area would likely be the loss of the Broadford-Smyth 138-kV circuit, followed by the loss of the Jacksons Ferry-Huffman 138-kV circuit. Consequently, voltage deviations would occur on the 138-kV system at 11 substations, the most significant being a 24% deviation at the Willis Gap substation.
The proposed lines, known as the Jacksons Ferry-Progress Park 138-kV circuit and the Jacksons Ferry-Wythe 138-kV circuit, will begin at the Jacksons Ferry substation in Wythe County and continue to a point near Wytheville, where they will then diverge.
The two lines will share ROW and supporting structures along the portion of the route from the Jacksons Ferry substation to the point of divergence.
At that point, staff added, the Jacksons Ferry-Progress Park 138-kV circuit will extend to the existing Progress Park substation in Wythe County, and the Jacksons Ferry-Wythe 138-kV circuit will extend on a separate ROW to the existing Wythe substation in Wytheville.
In addition to the lines, the company proposes supporting construction at the three substations.
Both routes – the preferred and viable alternative – begin at APCo’s Jacksons Ferry substation located about 1.5 miles east of the Foster Falls Village and three miles northeast of Poplar Camp, Va. Both routes exit the substation and head northwestward for about 2.3 miles, paralleling the western edge of an existing 765-kV transmission line ROW across Fosters Falls Mountain, spanning the New River and ascending Chestnut Ridge.
Staff also said that the preferred route continues westward for about 1.5 miles, crossing Chestnut Ridge, to intersect with an existing gas pipeline ROW adjacent to I-77. The route turns northwest and runs parallel to the pipeline and turns to the west, spans I-77, and continues northwest for about 1.2 miles just west of the closed Fort Chiswell Outlet Mall.
The route spans I-77/81, continues northwest for about 1.3 miles and then turns west for about 2.5 miles, crossing Route 121 about one mile south of Max Meadows. The double-circuit line splits into two single-circuit lines, each on its own ROW. One circuit continues northwest for about 0.5 mile, crosses over Reed Creek and the Norfolk Southern Railroad, and ends at APCo’s Progress Park substation located within the Wythe County Progress Park, staff added.
The other circuit continues west and southwest roughly parallel to the railroad and Reed Creek for about 1.75 miles and crosses I-77-81. The line continues southwestward for about 1.75 miles until it meets an existing 69-kV transmission line. From there, staff added, the line parallels the existing transmission line to the northwest for about one mile, crossing Reed Creek, entering Wytheville, spanning the railroad, Chapman Road and Route 11, and ending at APCo’s Wythe substation.
The project will not be built on existing easements, except where the new transmission line exits or enters a substation. Staff also said that new easements for the preferred route 100-foot ROW would be required for about 91 parcels.
The proposed project will require, among other things, the installation of one new transformer, two new 765-kV circuit breakers, six new 138-kV circuit breakers and about 2,300 feet of new 138-kV transformer connection line.
Staff also said that of the alternatives presented, the preferred route is the shortest route, affects the fewest number of residences and minimizes the total amount of forest clearing. APCo found that an underground route for the project would be impractical and that the estimated cost of an underground route could cost more than six times the cost of placing the same line overhead.
In a March 27 filing, APCo responded to the recommendations of the state environmental agencies incorporated into the DEQ coordinated review report submitted on Feb. 13.
Among other things, the company said it concurred with some of therecommendations, although it objected toa recommendationto maintain “naturally vegetated buffers of at least 100 feet in width around all on-site wetlands and on both sides of all perennial and intermittent streams where practicable.”
APCo said its experience shows that this recommendation may present safety and service reliability risks due to the potential for vegetation and wire contact from tall tree growth and therefore opposes it.
“[M]aintaining a 100-foot undisturbed wooded buffer within the right-of-way as recommended would require taller and heavier structures and additional line length, thereby unnecessarily increasing costs and visual presence,” APCo said.