The find has also prompted a subcontractor - speaking on condition of anonymity - to question whether workers were still being exposed to a hidden asbestos threat too often.
It was confirmed yesterday the university's $2.75million, 152-space car park had struck trouble after the remains of an asbestos roof were found buried under old building slabs.
The find, on December 16, meant a nine-week delay to the project, before some work resumed tentatively late last month.
The discovery and delays were also expected to add between $300,000 and $400,000 to the project's total cost, university property services director Barry MacKay said.
The find also prompted the unnamed subcontractor to contact the Otago Daily Times, concerned not enough was being done to check for asbestos at building sites before contractors went in.
''There's a lot of sites that get shut down [due to asbestos] after the workers have been through, running their services and stuff.
''It just concerns me. I've got a young family. I don't really want to retrain, but you're coming across it every week,'' he said.
Mr MacKay said an asbestos survey of the Wickliffe Press site had been conducted before demolition began, and had identified the buildings' roofs as containing asbestos.
They were removed by specialist contractors and demolition proceeded, but contractors then uncovered further ''asbestos roofing shards'' under the concrete slabs.
''This material was not identified in the original survey as it had been difficult to detect, as it lay underneath the existing structure,'' Mr MacKay said.
The site was shut down and WorkSafe notified, while a specialist was brought in to test the material, confirming it contained asbestos.
An asbestos removal control plan was put in place.The area was isolated, air tests were conducted and water was used to control dust, he said. Neighbours and university workers were advised. The plan would remain in place until the material was removed and further tests confirmed the area was safe, he said.
Air test results so far showed the amount of asbestos fibres in the air was ''well within safe exposure levels'' at the site and the neighbouring Information Technology Building, he said.
Mr MacKay said the university did have processes to identify asbestos ''where possible'', and deal with it, but did ''not always have the full history of the current building and, much less, the actual ground''.
''The materials under the old concrete floor in this case were a little harder to predict.''
The university had also carried out a campus-wide asbestos survey in 2015, identifying the extent of the issue it faced, offered asbestos awareness training to staff and had an asbestos management plan prepared, he said.
