Erosion visible from the Hampden Closed Landfill. Photo: Supplied/Waitaki District Council
Three sites containing historic waste are in danger of slipping into the sea and potentially causing an environmental disaster in the Waitaki District.
Two are illegal dumping sites on Beach Road, three kilometres south of Oamaru, and the third is the former Hampden landfill that sits next to the beach and closed in the 1990s.
The Waitaki District Council solid waste manager Steve Clarke said the council was acting now to remedy the situation.
Some waste has been removed and remediation has been done, but roughly 30,000 cubic metres of waste remains across the three sites, with 25,000m3 of it at the Hampden site.
"Many locals remember dumping their rubbish at one of these sites, and while they've said they never felt good about it, it was just the done thing," Clarke said.
"We know better now and are striving toward fixing the past and working toward a better future."
The waste from these sites could be received at the council's Palmerston Landfill and the Otago Regional Council has approved the move.
But the landfill closes in August 2027 once the consent expires, and it can not be renewed.
The nearest landfill that would receive the waste was the AB Lime landfill in Winton.
The council was also working on other longer term solutions, Clarke said.
The Beach Road sites were never opened or approved by council for landfill, but were believed to have been used between the 1950s to the 1970s.
They were partially remediated in 2017 and roughly 60 tonnes of waste was moved after rubbish was reportedly washing onto the beach.
Solid Waste Manager, Steve Clarke. Photo: Supplied/Waitaki District Council
The former Hampden landfill received an estimated 30,000m3 of waste while operating between 1970 to 1996.
Coastal erosion has already exposed previously buried waste and washed some of it onto the beach, with remedial work undertaken in 2009 to prevent further contamination.
That included removing part of the buried waste in the Palmerston landfill and the creation of a rocky slope to cover the edge of the landfill onto the beach.
Heritage, Environment and Regulatory group manager Roger Cook said the council has removed part of the waste.
"But with what we understand about coastal erosion and the expensive and destructive impacts of the waste falling into the sea, we need to take action now."
Request for proposal documents have been published and the successful bidder was expected to take possession of the sites from August.