It has also spent about $81,000 a year removing and taking contaminated water from the site at the former Dunedin Gasworks site, in Hillside Rd, for disposal at a Christchurch facility.
A council spokesman said the more than $2 million it had in this year’s budget to deal with the potentially cancer-causing chemicals and other toxic waste stored in the tar well underground at the site had been "pushed out" until its next long-term plan.
In January 2022, the council said it expected to have a remediation plan in place in the middle of that year.
This month, the council remained unable to release a preliminary feasibility report, the spokesman said.
"The feasibility report is still a work in progress and not yet able to be released.
"Funding for any future remediation of the site has been pushed out alongside timelines for this project, but will be included in the draft nine-year plan to be considered by council next year."
The former city-owned gasworks stopped operating in 1987.
Nearly a decade ago, engineering consultants MWH told the council the cost of remediation and disposal for the site could be significant.
The council received $200,000 for the feasibility assessment and the development of a remediation plan in September 2021 when the Otago Regional Council secured funding from the Ministry for the Environment’s contaminated sites remediation fund for the project.
At the time, the city council said it had $2.64m budgeted in its 10-year plan for the cleanup.
The bulk of the money was to be spent this year ($2.1m) with the rest intended to be spent next year ($540,000).
The council spokesman said the council had spent about $300,000 since 2021 on the detailed investigation and planning stages of the project, and about $81,000 a year since 2017 on the removal, transportation and safe disposal of contaminated water from the tar well site at a Christchurch facility.
"Detailed investigation and planning are vital parts of this project, given the complexities of the work involved, as is our work to make sure the site remains well managed, monitored and contained in the meantime.
"We also remain in close contact with the Otago Regional Council and Ministry for the Environment to keep both parties updated about the progress being made," he said.