Contaminated land on Oamaru's foreshore is being capped with sand, clay and soil to be redeveloped as open space and landscaped as part of the harbour redevelopment.
A timber treatment plant once operated on the site between the old railway line to the harbour and the foreshore, south of Oamaru Creek.
Remedial work, including a containment cell with concrete capping to hold some contaminated material, was done in the 1990s after the plant had been closed for at least a decade and fears were raised about arsenic and other contamination from the timber treatment chemicals.
Now, further capping is being done after investigations and analysis found areas of arsenic soil contamination above acceptable limits (80mg/kg of soil).
Last year the Waitaki District Council, which owns the land, made up to $145,000 available from its hazards mitigation fund, along with a grant from the Ministry for the Environment through the Otago Regional Council, for the work.
The area was fenced about three weeks ago and a 300m-long concrete retaining wall built alongside the last leg of the Alps 2 Ocean cycleway and path which runs along the foreshore.
About 6000-7000 cubic metres of sand is being dug out of the bay in the southeast corner of the Oamaru Harbour, then transported and spread across the affected area. It will be covered by clay and soil and landscaped.
Taking sand from the bay will also enable the council to see if that helps reduce silting of the Oamaru Harbour and its entrance.
The final cost of the job will not be known until it is completed in about two months and issues such as landscaping finalised.
A management plan will be developed for the area, which will include future monitoring of contamination.
