The white van comes under cover of darkness. It's quiet and quick, it's a secret after all, but by the time garbage trucks arrive with the early morning light, many bins across the Queanbeyan-Palerang region are already empty.
For the past fortnight, the mystery of the disappearing rubbish has had locals scratching their heads - and some crying foul.
One resident whose bin was hit in the early morning sweep described it as "creepy", and estimated just one bin per street was unloaded each Thursday.
"I assume it's something for the council but you do think who's going through my rubbish? There hasn't even been a note in the mail," she said.
Bungendore residents took to social media to share stories of the van, some voicing their alarm or displeasure at the "intrusion".
Councillor for the Queanbeyan-Palerang area Peter Marshall revealed the secret behind the pre-dawn collection on Thursday, confirming to Fairfax Media that the collection was part of a council audit of waste in the area.
Households were selected at random, Mr Marshall said. He understood their rubbish was kept confidential and later returned to the usual tip for disposal.
"It's kept secret in advance so that people don't change their practices knowing that their bin might be in the sample," he said.
On Friday afternoon, the council also came clean, moving to reassure residents "there's been nothing sinister going on" and the final collection in the audit had been carried out that morning.
"Some residents have resorted to social media to find out what has been happening, but until now Council has remained quiet about the activity because of the risk that any publicity could have changed people's behaviour and jeopardised a very important project," the council said in a statement.
A council spokesman said the van did have lettering on its side declaring it to be a "council contractor", but operating about 5am in the dead of night, it is unlikely this was seen by locals.
A similar audit had been undertaken in 2015 and its findings formed part of recommendations to council on waste management.
This month's audit would also inform the council's new waste strategy, to begin in mid-2018.
"It will also determine the amount of eligible containers in recycling bins for the Return and Earn scheme so that negotiations can begin with the Materials Recovery Centre in respect to refunds," the spokesman said.
While Mr Marshall had previously reassured some residents on Facebook that the collection was all "Kosher", not everyone was satisfied with the explanation.
"I understand the council's intentions are honourable but covertly collecting our rubbish and sifting through it without our permission or any notification feels like a breach of privacy," the resident said.
While the council had received a "small number of enquiries" about the collection, waste audits were a normal activity of councils across Australia, the spokesman said.
Similar bin audits have been conducted by the ACT government in recent years.