Findings of the review by Deloitte indicated that the most common issues were incorrect payment for the casual minimum engagement period (59 per cent of payments) and for weekend and public holiday overtime (29 per cent of payments).

The underpayments were in breach of workplace agreements the university made with staff in 2013 and 2018.

Back payments will include superannuation and interest. The university said it will not ask anyone who has been overpaid to repay any money.

Universities have been placed on a watch list this year by the Fair Work Ombudsman over systemic underpayments of casual staff.

The university has committed to reviewing its heavy reliance on casual labour. According to its most recent annual report,51.5 per cent of employees are on fixed-term or casual contracts.

“In 2022,the university will review its approach to workforce planning to reduce reliance on casual employment,recognising that workforce structures which rely heavily on casual employment are neither desirable nor sustainable,” its 2021 report said.

The union’s University of Melbourne branch is pushing for at least 80 per cent of staff to be employed in ongoing roles.

Branch secretary David Gonzalez said the university should come to the bargaining table to negotiate if it is serious about reducing its reliance on casual staff.

“We can’t wait any longer for secure work. Solving the scourge of wage theft can only be accomplished if casual work is dramatically reduced at the University of Melbourne,” Gonzalez said.

The Fair Work Ombudsman said late last year that it was investigating potential wage theft at 14 Australian universities.Separately,it is also pursuing Melbourne University in court,alleging it coerced and took adverse action against two casual academics to stop them from claiming payment for work performed.

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