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Energy / Ground investigation work for future power set-up to get underway this week

Photo: SSEN Transmission

GROUND investigation works are set to begin this week in preparation for the transmission link being laid, which will connect Shetland to the national grid.

The work will allow teams from SSEN Transmission to examine sections of the route.

The cable, which will run from Caithness into Weisdale Voe, is expected to go live in 2024 once the Viking Energy wind farm is operational.

The ground investigations will take place along the proposed 132kV electricity transmission network overhead line and cable route between these sections: Kergord and Gremista; Kergord and Cul Ness on the mainland; and Burravoe and the proposed switching station and Beaw Field windfarm substation in south Yell.

Works will start from today (Thursday) at the sections between Kergord to Gremista and in Yell, before moving onto the other section between Kergord and Cul Ness.

The work is expected to take place over eight weeks, with work programmed to be completed in early June, weather permitting.

As part of the Shetland Connections project, the work will be undertaken by specialist contractor BAM Ritchies with local firms providing plant hire, fencing and local support services.

Ground investigation works are said to be a key part of the project development process and the results of these investigations will provide the project with “valuable information to help inform the final design of the proposed onshore overhead line and cable routes, providing connections back to Kergord substation which is currently in construction as part of the Shetland HVDC link”.

Up to 25 people working across five teams will be undertaking the works, which will include drilling boreholes and excavating trial pits, as well as monitoring and conducting environmental and archaeological surveys where necessary.

Overseeing the works will be a team of environmental and archaeological specialists who will ensure any environmental impact is monitored and kept to a minimum.

To carry out the ground investigations around 300 trial pits will be excavated and around 40 boreholes will be drilled with rigs towed by specialised low ground pressure vehicles, which are used for their low impact on peat lands.

In addition, two low ground pressure excavators will be used for excavating trial pits on the more sensitive areas and one standard tracked excavator will also be used on more stable ground condition areas.

There will be two compound areas set up to cover the works with the main site being in Lerwick and a satellite compound set up in the Burravoe Hall car park in Yell.

Landowners and tenants will be informed with more detailed information on dates of works to be carried out on their property.

Temporary traffic lights will be in place on the A970 and B9071 for short durations of one to two hours only to allow the project to be carried out safely and to ensure disruption to road users is kept to a minimum.

All local residents and relevant stakeholders have been informed about the project in advance to advise about the work taking place and minimise any impact.

SSEN Transmission project manager Edward Holten said:  “This is a key step in our plans to build the Kergord to Gremista and Kergord to Yell connections, which will allow us to investigate the ground conditions in the area to inform our final engineering design.

“The two 22km circuits between Kergord and Gremista, which will be a combination of overhead line and underground cabling, will provide a connection between the proposed Gremista GSP and Kergord substation, which is currently in construction as part of the Shetland HVDC link.

“Upon completion, this will provide a connection to Shetland’s local electricity distribution network, connecting the islands to the GB electricity network for the first time, helping secure Shetland’s future security of supply.

“Ahead of works we would like to thank the local community for their patience while we carry out these essential ground investigation works. We will work to keep disruption to a minimum at all times and apologise in advance for any inconvenience which may be caused.”