Land slip at Wollongong coal mine still needs more repair work

The company had to seek permission to work "out of hours" from the NSW Department of Planning and Environment (DPE), in order to deal with last week's slip which was near a conveyor portal to bring coal out.

Residents reported loud noises in the night last weekend, suspected to be explosives. The night work exemption was meant to last until Tuesday but has now been extended to Monday, July 25.

"The continued emergency works include structural improvements to required due to changes in ground stability, the development of further fracturing, and continued control room movement monitoring," Wollongong Coal told nearby residents in a letter drop on Wednesday.

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The Mercury understands there was some internal damage to the portal but it did not collapse and was not blocked.

Remedial work has included bracing inside and outside the portal, with the site being checked twice a day.

On Friday a company spokesman told the Mercury there had been no risk to workers or neighbours.

"Wollongong Resources can confirm that there had been a localised land slip near the vicinity of its conveyor portal that is small by nature and of no risk to adjoining property owners," he said.

"It has been caused by the recent heavy rain and is unfortunately a common event within the escarpment.

"Due the necessity to stabilise the area with traditional civil techniques we had gained permission from the DPE to extend our normal working hours and potential noise limitations.

"This included notifying all neighbours that may be affected. There was no risk to our workforce nor our local community."

Questions as to the precise location, or whether explosives had been used, did not receive an answer.

DPE compliance officers have visited the site.