A developer will be issued with a final clean up notice to remove rubbish left on land at Nattai Ponds.
The rubbish which includes a large amount of building products has been left at the site for months.
A number of local residents have since raised concerns about the effects on the waterway at the back of Nattai Ponds in Mittagong.
Back in November, Wingecarribee Council Rangers issued the owner with a 21 day notice to clean up, but nothing was done.
A final notice will now be issued, and if nothing happens in 12 days, council will clean it up and then invoice the owner.