Workers on the Snowy Hydro 2.0 project are threatening to walk off the job over conditions, saying safety is being compromised and workers have been served maggot-infested food.
The Australian Workers' Union has released photos of steak riddled with maggots allegedly served on the site in the NSW Kosciuszko National Park where workers are building a national renewable energy project.
AWU NSW Secretary Tony Callinan said the food being served was indicative of a broader management problem on the site.
"Supermax prisoners are served better food than the workers building Snowy Hydro 2.0," Mr Callinan said in a statement on Tuesday.
"You have workers living, literally locked up in a camp with limited recreational facilities in the middle of nowhere, being fed maggot-infested food.
"The site has an abysmal safety record. It's an absolute pressure cooker right now."
Many workers were living off canned tuna and two-minute noodles and were threatening to walk off the job.
"The problem is the joint venture who was awarded the contract is pinching every penny they can to try and improve their profit margin," Mr Callinan alleged.
The union also claims it receives regular reports of serious safety issues on the site.
"The whole site's a tragedy waiting to happen," Mr Callinan said.
Comment is being sought from Snowy Hydro.