The council say they are “investigating further” after images were shared on social media of alleged run-offs from Viking Energy construction work running into the Sandwater loch.
Sustainable Shetland shared pictures on Facebook which the group said showed material from the “borrow pit” making its way into the loch.
The SIC said on Tuesday night they had received “a number of complaints” on this, and that they were now “investigating further”.
A member of Sustainable Shetland, who contacted The Shetland Times about the images, said that Sepa had also been notified.
Viking Energy have not responded to a request for comment.