Comhairle nan Eilean Siar’s planning board yesterday (Wednesday) agreed to permit the first phase of work on the Lewis Hub. It will come before full council this afternoon.

However, concerns were raised about potential damage to the main Stornoway to Tarbert A859 road from work to excavate and build up the adjacent ground to enable heavy loads to access the site.

Councillor John Norman Macleod, representing An Taobh Siar Agus Nis, raised fears about the peat depth, the amount of water that could seep out, and potential sinking of the road at this point.

He put forward an amendment, suggested by planning officer Morag Ferguson, to approve the report subject to this site access work being taken out and derogated for further investigation. The amendment was agreed and will go to the full Comhairle.

The planning board was considering a report from planning officers which recommended approval for the initial enabling works on the strategic electricity transmission hub near Arnish. The report concerns the first application out of an expected three for the project around two kilometres south-west of Stornoway.

The application is for SSEN Transmission’s construction of the substation and converter station on the Arnish Moor. It involves a 16-month construction programme involving heavy groundworks, rock blasting and extensive peatland restoration.

It is vital work for the Western Isles HVDC Link Project – the interconnector which aims to connect 1.8GW of renewable energy capacity to the mainland grid.

The report presented to the planning board advised that approval be granted subject to finalising outstanding landscape mitigation conditions.

The original proposal was for 285 hectares across two sites but one of those areas, Creed North, has been dropped and it is now focused solely on the Arnish Moor site, which is 127 hectares.

Planning officer Morag Ferguson said this was “still a significant area” as she spoke to the report.

It will include the construction of two platforms. The first will be for the AC Substation and will cover an area of 260 metres by 250 metres while the second, for the HVDC Converter Station, will extend to 320 metres by 310 metres.

There will be extensive rock and peat excavation and Ms Ferguson stressed the proposed landscaping was “a very critical part of this application”, as was noise mitigation associated with the rock extraction.

Councillor John Norman Macleod raised concerns over work that would be needed for the permanent site access from the main A859 road.

He questioned the extent of knowledge around the peat depths, given the work that was going to be necessary on the site access junction in order to support heavy loads.

He asked if we knew “what was under the A859” road itself.

Cllr Macleod: “I am concerned about the A859 and what’s underneath it. If we take all the peat out of there, that’s beside that road, there’s nothing to stop the water in the peat under the A859 seeping out… which would then cause the road obviously to sink.”

He asked: “Would it not be better to find out before we proceed?’

Ms Ferguson suggested that be added to the matters to be derogated for colleagues to provide more information.

Cllr Macleod proposed an amendment to that effect, having stressed: “I would like to see more info on that particular access before I put my name to say I’m happy with the planning permission.”

He wanted more information about what is underneath the road, how it will be built and how it will be supported.

Also at the meeting, Cllr Angus McCormack of Steornabhagh a Deas – not a member of the planning board – asked a question about landscaping on behalf of Sandwick residents.

He asked about the bunding that would be done to the east of the site.

He said: “The principle matter that’s been raised with me is the view from Lower Sandwick over towards the site and I wonder if we are satisfied that the bunding on the east of the site will be such that it at least diminishes the impact over that stretch of water?”

Ms Ferguson responded with assurances that landscaping was being “looked at very carefully” and the Comhairle had brought in its own landscaping consultants to provide “specialist advice” but “we haven’t completely bottomed that out which is why we’re seeking derogation for it”.

Landscaping recommendations include, among other measures, an earth bund of nine metres high and 220 metres long along the eastern side to screen the converter platform.