Parent Paula Loustos alerted the school and Environment Protection Authority to the issue about three weeks ago, after residents noticed smoke and a burnt, gassy smell emanating from the earth next to the school.

On Monday, she addressed Wollongong council, calling for assurances about the safety of her children and others.

“This is not a normal smell for Cringila, it smells like the coke ovens from years ago,” Ms Loustos told councillors.

“How come we can smell it streets away? Why does nothing grow well there? We need documented evidence to state that our children are and always have been safe.”

The fenced-off site between the school and its sportsfields last drew attention in 2007, when the NSW education department – which owns the land – undertook major remediation works to extinguish a fire burning several metres underground.

The fire had been burning for decades unnoticed until 2001. It was caused by coal wash dumped on the site by BHP to create the school’s playground in the 1970s. The material was not compacted sufficiently, so the oxygen in the air reacted with the coal wash and spontaneous combustion kicked in. 

The day after Ms Loustos raised the issue with Cringila Public School on September 18, the education department launched an investigation with Fire and Rescue NSW, NSW Health and the EPA to find the source of the new smoke.

This revealed that a long spell of dry weather, and subsequent drop in the water table, had resulted in ignition of the underground coal.

Fire crews attended and flooded the area with water in an effort to stop the ground from smouldering.

However, weeks later residents say the smoke has not stopped, and when the Mercury attended the site on Tuesday, a burning coal smell was still evident next to the fenced off area.

“The safety authorities monitored the site to determine the nature of the smoke emanating from underground and determined that there was no danger to the school community,” a spokeswoman from the department of education, leading the inquiry, said.

“The area in question will continue to remain cordoned off, and measures undertaken to keep the site secure while the department continues to carry out ground and air monitoring.”

The school is on the EPA’s register of contaminated sites, but is listed as not requiring regulation under the management act.

While the site is not council land, Wollongong Lord Mayor Gordon Bradbery has met with Ms Loustos about her concerns.

“A couple of weeks ago, when it was first noticed, Paula and I had a look at the site, and when we arrived the HAZMAT people were there pouring water into it where it was venting out of the ground,” he said.

“Children aren’t playing there, it is fenced off and there are concrete and clay barriers that have been put around it in the ground.”

He said the issue was now in the education department’s hands as the investigation continues.

Parents have been notified about the issue and will be kept informed.

“The health and safety of students, staff and the school community is of utmost importance to the NSW Department of Education and everything possible is being done so that the school site remains safe for our students,” the spokeswoman said.

“The department, once further information on the extent of the issue is known, will investigate options to manage the site, in conjunction with specialist agencies.”