Unite Scotland has blasted the decision by Worley to announce job losses at Sullom Voe Terminal.
Worley operates the gas export pipeline to the terminal.
The company has refused to furlough its 27-strong workforce and are instead making them redundant.
Unite said Worley had blamed the proposed redundancies on the need to make cost savings due to the significant fall in the price of oil and by the added pressures to their business from the coronavirus pandemic.
The union highlighted that Bilfinger, another contractor on site, furloughed its workforce following discussions in late March.
Unite stressed that it would “continue to push Worley to reverse this decision on all redundancies” and would explore all legal options, including the possibility of lodging unfair dismissal cases on behalf of the workers.
Unite regional officer John Boland said: “It is a disgraceful way to treat a workforce that have worked at Sullom Voe for many years, to discard them with no care or thought as to how they will survive.
“It’s clear that Worley is only interested in itself, and has no regard for the workforce. We urge the company to look at how the government scheme can be used to support the workers during this difficult time by delaying the redundancies as Bilfinger has done.
“If they don’t do the right thing then Unite will consider all actions in order to support the workforce including the possibility of lodging unfair dismissal cases on their behalf.”