Frequently asked questions about contaminated land
What is contaminated land?
How does land become contaminated?
When is contaminated land a problem?
What can I do if I am concerned my land is contaminated?
Who manages contaminated land?
Where can I find out more information?
What is contaminated land?
Under the Resource Management Act, contaminated land is land with hazardous substances in or on the land that are reasonably likely to have significant adverse effects on the environment (including human health).
The full definition of contaminated land under section 2 of the Resource Management Act is:
“contaminated land means land that has a hazardous substance in or on it that -
(a) has significant adverse effects on the environment; or
(b) is reasonably likely to have significant adverse effects on the environment”
How does land become contaminated?
The inappropriate storage and use of hazardous substances and disposal of hazardous wastes can result in the contamination of the environment. Contamination is not always limited to a specific site: hazardous substances may seep through the soil into groundwater, or be carried to nearby land and waterways in rainwater or as dust. Hazardous gases can also pollute the air.
Some land in New Zealand has been contaminated as a result of industrial, domestic or agricultural activities. In particular, the manufacture and use of pesticides, fertilisers, production of coal and gas, mining, timber treatment and sheep dipping are activities commonly associated with contaminated sites in New Zealand. Many of these activities – for example, the use of dieldrin in sheep dips and to kill insects in the 1940s to the 1960s – were not considered as hazardous at the time.
When is contaminated land a problem?
Contaminated land is a problem when the hazardous substances are at a concentration and/or are located where they have, or are reasonably likely to have, a significant adverse effect on human health and the environment. Contaminated land is a more urgent problem when contaminants are close to buildings and people, or close to water bodies and important habitats.
People, animals and the environment can be exposed to hazardous substances on contaminated land by:
- direct contact with contaminated soil
- swallowing food or water from contaminated environments
- breathing vapours or contaminated dust .
As well as endangering health, these substances can:
- limit the use of land
- cause corrosion that may be threaten building structures
- reduce land value.
As land is increasingly developed in New Zealand, it is important to know where contaminated land is located so people are not exposed to contaminants that may affect their health.
To help with identifying potentially contaminated land, the Ministry of the Environment has compiled a list of activities and industries commonly associated with contaminated land This list is called the Hazardous Activities and Industries List (HAIL).
Local authorities may use the HAIL to identify potentially contaminated sites. Further investigation of an individual site is required to determine whether the site is contaminated.
What can I do if I am concerned my land is contaminated?
If you are concerned that your land is contaminated check out our How to find out if your land is contaminated web page.
Who manages contaminated land?
The Ministry for the Environment is responsible for administering the Resource Management Act (RMA) 1991. The RMA is the core piece of environmental legislation for controlling the effects of contaminated land on the environment and people.
Local government (regional councils, city and district councils) are responsible for the day-to-day management of contaminated land and have specific functions under the RMA. Local government is in charge of controlling the effects of contaminated land, and also for controlling activities that cause land to become contaminated. Sections 30 and 31 of the RMA give local government the following functions:
- regional councils – “the investigation of land for the purposes of identifying and monitoring contaminated land”
- district and city councils – “the prevention or mitigation of any adverse effects of the development, subdivision, or use of contaminated land”.
These functions generally mean that regional councils work to identify and monitor the environmental effects of land that is contaminated within their region. District and city councils are responsible for checking, before approving a subdivision, development or change of land use, that health guideline levels are not exceeded for any contaminants present In addition to the RMA functions, local authorities also have responsibilities under other Acts to provide information about the presence of hazardous substances on land.
More information on the roles and legislative responsibilities see existing measures for managing contaminated land in New Zealand.
Where can I find out more information?
For the public
For information about contaminated land in your region, contact contaminated sites staff at your regional council. Links to council websites can be found from the Local Government New Zealand website. The following regional council websites also have good information about contaminated land:
For regional and district councils
Guidance for regional and district councils can be found on the Ministry for the Environment’s contaminated land management guidelines web pages.
For more information about any of the Ministry’s work on contaminated land please see: Contaminated land managementor email standards@mfe.govt.nz.
Last updated: 7 July 2011
