The Dunedin City Council signalled about $37.8m would be set aside over the later years of the 2025-34 draft long-term plan for remediation of the former landfill under Kettle Park sports fields, beside Middle Beach.
Landfill material there is at risk of being exposed by coastal erosion.
The threat is being headed off by geo-textile bags on the beach for the moment, but work on a permanent fix could start in 2030-31.
A remedy is likely to include excavation of material.
A report for a city council meeting today highlighted $5.9m was indicated in draft budgets for 2030-31, and then $10.6m, $10.7m and $10.7m in the following three years.
This would need to be covered by rates, although the council has also previously signalled external funding bids are likely.
The council was unable to confirm yesterday what might be required beyond 2034.
What it has said is contaminated material from Kettle Park would end up at the Smooth Hill landfill, which is due to open in 2029.
Dunedin Mayor Jules Radich last year described landfill material beneath Kettle Park as a toxic threat to a stunning coastline.
The council had also said in 2023 the landfill site was larger and closer to the sea than had been thought.
Kettle Park operated as a landfill from about 1900 to the 1950s.
The landfill was capped in the 1960s and sports fields were developed there.
An investigation by Tonkin + Taylor completed in 2023 found concentrations of copper, lead and zinc were generally elevated at the locations it tested.
Most results for the three metals exceeded screening criteria for a Ministry for the Environment class-A landfill or the private Burnside landfill.
The results indicated landfill materials would require some form of pre-treatment to reduce leachability.
A council staff report at the time said contaminants in the landfill and capping materials were at concentrations that presented a potential health risk, but they were covered by layers of topsoil and turf.
Health risk for users of the sports fields remained low.
