The Vermont Public Service Board (PSB), in a June 29 final order, adopted the findings, conclusions and recommendations of a hearing officer, who had recommended that the PSB approve the PV20 Cable Replacement Project, and issue a certificate of public good (CPG), subject to conditions.
As noted in the order, Vermont Transco LLC and Vermont Electric Power Company (VELCO) last September filed a petition requesting the CPG for the construction of the project, which consists of the replacement of submarine transmission line and termination and control equipment; the installation of connecting line structures; and the removal of the former submarine transmission line, termination structures, and connecting line structures, all located within the town of Grand Isle, Vt.
A technical hearing was held on April 28.
As TransmissionHub reported, the existing PV20 circuit connects the New York Power Authority (NYPA) Plattsburgh substation in Beekmantown, N.Y., to the VELCO-Sand Bar substation in Milton, Vt., VELCO said in its petition. A portion of that circuit runs underwater (submarine) in Lake Champlain between Plattsburgh, N.Y., and Grand Isle. The existing submarine segment of the circuit consists of four cables installed in 1958, and three cables installed in 1970. The existing cables are damaged, with one being no longer usable, and are at the end of their expected useful service life, VELCO added.
“Replacing the existing cables and termination stations in Vermont and New York, and rerouting terrestrial and overhead portions of the PV20 line, is necessary to maintain this vital high-voltage circuit,” VELCO said.
The project seeks to:
- Replace the VELCO-owned segment of the PV20 circuit from the New York border, located underwater within Lake Champlain, to the overhead point of interconnection, located in Grand Isle
- Replace the existing Grand Isle termination station with a new termination station, to be located north of the existing station
- Reroute the overhead transmission line with the installation of two new transmission structures
- Remove the existing cables
- Remove the existing Grand Isle termination station and its associated equipment
- Remove two no-longer-required overhead line structures
The total estimated cost of the PV20 removal and replacement in New York and Vermont is $91.6m, which is comprised of $83.3m for the installation of new cables, spare cable and structures, and $8.3m for the removal of existing cables and structures, VELCO said. The estimated capital cost for VELCO’s portion of the installations is $45.1m, and the estimated cost for VELCO’s portion of the removals is $4.6m.
VELCO also said that its schedule calls for work on the access road, site grading and horizontal directional drilling to begin this year, and with primary construction beginning in the spring of 2017. The project is scheduled to be completed by the winter of 2017, and the removal of the existing facilities in 2018.
According to the PSB’s order, the project is required to meet the need for present and future demand for service that could not otherwise be provided in a more cost-effective manner through energy conservation programs and measures, as well as energy efficiency and load management measures.
Also, operating the PV20 circuit in a reduced capacity would negatively affect wind generation in New York, reduce VELCO’s ability to conduct day-to-day maintenance activities, and reduce import capacity into the northwest Vermont region. The order further noted that the project would not have an undue adverse impact on system stability and reliability.
In addition, the project would not have an undue adverse effect on aesthetics, historic sites, air and water purity, the natural environment, or public health and safety, the order said.
The project presents the risk of introducing aquatic invasive species (AIS) into the lake through the use of vessels, such as barges and tug boats, that travel from the New York and New Jersey metropolitan areas, along a substantial length of the Hudson River, and through the Champlain Canal en route to the project site. The order added that an AIS mitigation plan is necessary to avoid undue adverse impacts to the lake.
While no threatened or endangered species or necessary wildlife habitat are within the aquatic or terrestrial project areas, as a means to preserve and protect fish and wildlife habitat, VELCO has agreed to seasonal restrictions for lakebed-disturbing activities and to obtain advance approval from the Vermont Agency of Natural Resources (ANR) for any permanent removal of woody debris, trees, stumps, historical sawn logs, rock, aquatic plants, or animal life from the lake during installation and removal activities, other than for incidental removal of small items, the order said.
Among other things, the order said that VELCO is to restrict construction activities and related deliveries, except during required outages or as required by other permits, to the hours between 7 a.m., and 7 p.m., Monday through Friday, and between 8 a.m., and 5 p.m., on Saturdays, and is to cease construction activities on Sundays, as well as on state and federal holidays.
Additionally, VELCO is to limit lakebed-disturbing activities – which include activities related to cable installation and cable removal – to the period from June 1 to Oct. 1, the order said.