A document seen by the Otago Daily Times showed the Department of Conservation (Doc) was sourcing tenders for the work, which includes the removal of existing contaminated material and coastal protection by the construction of a rock revetment seawall.
It stated coastal erosion along the seaward edge of the landfill had resulted in the exposure of waste material on the foreshore, with about 90m of the beach being the area more affected.
"Investigations identified the presence of contaminants, including asbestos, in the landfill material at concentrations which present a potential risk to human health and the marine environment," the document said.
"As such, remedial works need to be completed to address the coastal erosion and contamination."
Doc operations manager Murihiku John McCarroll said the presence of asbestos was first noted near Ocean Beach in early 2018 and an initial site inspection was completed.
"Elevated concentrations of heavy metals and asbestos have been identified at the coastal edge of the landfill, along with physical hazards such as sharp objects."
Since then, an asbestos removal company had already cleared about 1.2 tonnes from the beach, he said.
He understood the landfill was composed mainly of demolition material from buildings that were once part of the former Ocean Beach freezing works, Mr McCarroll said.
"The asbestos fragments collected have varied in size from very small to a little bit bigger than the size of your hand.
"The total extent of contamination is linked to the size of the landfill, which extends inland."
The presence of asbestos presented a risk to human health and airborne fibres were harmful if inhaled.
He said Doc staff carried out monthly photographic inspections from specific location points to monitor the site.
"Our advice is for people to avoid exposed landfill material and do not disturb the ground or foreshore. This advice appears on signage at the site.
"We have been working hard to mitigate any public risk through asbestos and steelwork beach removals, regular site monitoring by Doc staff and annual site risk assessments to ensure reasonable mitigation measures."
The work planned for next year was expected to start by April or May and would likely affect public access, as the site would be fenced off as a construction compound, restricting all access to the beach and neighbouring walking tracks, Mr McCarroll said.
"A remedial action plan has been completed to identify the most appropriate long-term management options for the site. Proposed work included rock armouring along the beach area to protect the actively eroding portion of the landfill, monitoring and assessing the balance of the landfill into the future allowing for sea level rise and identifying any future risk to the site.
"Public safety will be paramount during any work on site and there will be notifications of any restrictions as early as possible."
Environment Minister Penny Simmonds this week announced a $30 million fund to help councils and landowners clean up historic landfills and other contaminated sites that are vulnerable to the effects of severe weather.
“With this new fund, we will safeguard New Zealand’s natural beauty and the wellbeing of our communities for future generations," she said.
Ocean Beach has been awarded $534,750 from that fund.