In a rare show of disunity with the administration, Cr Bradbery has chastised council staff and said they needed to "lift their game" after fragments of bonded asbestos were found in piles of council waste between Bulli Tops and Waterfall this week.

The mounds of soil and other construction materials were placed along the highway by council staff in recent weeks, as part of a three-year "internal staff initiative" designed to deter other dumpers.

"This will be part of the assessment of the general manager's performance, because he is responsible for staff and he will have to be responsible for the discipline within the organisation," Cr Bradbery said. "The message is coming through loud and clear from myself and other councillors that this is not good enough.

"The issue is not so much the fact I fear anyone's health is at stake, but I am concerned about the message this is sending to the community."

"It's highlighted a weakness that needs to be addressed and it's the general manager's task to do so."

Cr Bradbery will use a lord mayoral minute at Monday's council meeting to ask Mr Farmer to review why and how the dumping could have happened.

"I'm requesting ... a total review on where we access soil and fill for such projects and the mechanism we use to check for contamination," Cr Bradbery said.

"I'm also asking the general manager to review our training of staff and, under this particular matter, what disciplinary actions are going to be taken as well."

Asked if he was happy with the way the council had handled the fallout from its botched dumping scheme, Cr Bradbery said he did not believe the administration's actions had been "adequate".

"It's highlighted a weakness in the organisation," he said.

"It really just requires better systems, better checking and more specifically a look at the history of the materials we're using."

He will ask Mr Farmer to report back by the end of June about the actions he has taken and what remediation has been put in place.

Other councillors have also raised concerns about the program, with Greg Petty saying he was disappointed by the lack of information supplied to councillors.

"It would have been nice if they told us they were doing this 'trial'," he said.

He also said he was concerned about the number of times the Environment Protection Authority had investigated the council over its waste processes in the past three years, and thought the concept of dumping construction waste to deter illegal dumping was "illogical".

"The council has said this is to prevent dumping, but in front of one of the piles already there's already another dump," Cr Petty said.

Vicki Curran said she was alarmed to find out about the "hypocritical" scheme, and believed councillors should have been informed of the dumping trial before it started so that they could be certain the right environmental checks had been put in place.

Liberal councillor Leigh Colacino said he was happy with the concept of placing construction waste along the roads to deter dumpers, but said it was "a real shame" the material had been found to be contaminated.

Wollongong City Council has spun into damage control after it dumped toxic material along the Old Princes Highway, with its public relations department emailing councillors a handy cheat sheet of answers to tricky media questions.

Councillors were alerted that asbestos fragments had been found in piles of council construction waste between Bulli Tops and Waterfall just 12 minutes before two top bureaucrats fronted a press conference to admit the mistake to local media.

"Over the last few days there has been some community and media interest in the mounds placed by council on the old Princes Highway to deter illegal dumping," public relations manager Susan Wardle told the councillors in the email.

"I have attached a statement relating to the matter for your information as well as some likely questions and proposed answers."

In the email Ms Wardle also informed councillors they had already been "provided with information about this matter". However, she later told the Mercury that the same email was the first time they had been told about the practice of using construction waste to deter illegal dumpers.

When asked if it was usual practice for staff to feed elected representatives a script about a council matter, Ms Wardle said it is not uncommon for staff to prepare background or briefing notes for senior staff who may address the media or the public, and the background was given to councillors for their information.'