A minister has been forced to explain why more than 200 staff were being paid to work at Perth's new Fiona Stanley Hospital despite there being no patients due for eight months.
Despite delays to the opening of the $2 billion hospital, 230 staff from under-fire contractor Serco are already in place.
WA's health minister Kim Hames admitted the staff were being paid to prepare and maintain the hospital ahead of its staged opening beginning in October.
"About the half of those are getting ready, getting set up and maintaining the grounds," Dr Hames told Fairfax radio.
"There is a huge amount of work to be done, all the fitting needs to be done, we have got to put in equipment, all the beds, all the linen - all the stuff that you need to run a big hospital when it is fully operational.
"It is a big job, and a big hospital."
Serco's relationship with the Barnett government has been brought into question in recent weeks, following a series of escapes from prisons and detention centres being staffed by the private contractor.
Dr Hames said hundreds of medical staff were also already in positions at the hospital, some of them while employed at other hospitals, Dr Hames said.
"They are not sitting on their bum doing nothing, they are planning the whole service that will sit under their control," Dr Hames said.
The WA government has copped previous criticism after other health projects were "reprioritised" to free up tens of millions for a computing system at the Fiona Stanley Hospital.
The six-month delay in commissioning the new hospital - attributed to the complexity of a "paperless" computing system - is estimated to cost more than $50 million in fees to Serco.
The state opposition labelled the latest revelation as an "outrageous waste".