Hundreds of homeowners in Napier have been warned they could be living on a contaminated former dump site.
Hawke's Bay Regional Council has sent letters to about 350 affected properties around Onekawa Park, telling them part or all of their properties may be located over the former dump, and that it could be contaminated with methane and toxic heavy metals.
The Onekawa site was used as a landfill until the 1930s and loaded with rubble after the 1931 earthquake, but authorities do not know its precise boundaries.
The council has known about the site for at least a decade, but is taking action now because of an Ombudsman's ruling that the information could not be withheld from the media.
Long-time residents in the area say they have always known about the dump, and believe any contamination is well buried.
Resident Tim Davidson says some parts of the area have been subsiding but he has no reason to think there is any danger of contamination, and some locals are angry the past is being raked up.
100 possible sites in Manawatu-Wanganui
The Manawatu-Wanganui Regional Council says it has no timetable for investigating all the possibly contaminated sites in its region.
The council has released its list after a request was made by Radio New Zealand under the Official Information Act.
The list shows more than 100 possible sites which have not yet been investigated and 16 sites where contamination is known to exist but has not been cleaned up.
The council's environmental protection manager, Alison Russell, says consultants have assessed the contaminated sites and there are no immediate safety issues.
However, Ms Russell says she does not know how long it will take for the others to be investigated and the list is being processed on a case-by-case basis as resources allow.