What is a Contaminated Site?

Land is considered to be contaminated when hazardous substances are present at levels above background levels and they are likely to pose an immediate or long-term risk to human health or the environment.

People, animals and the environment can be exposed to hazardous substances on contaminated land in a number of ways, including:

• 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 threaten building structures
• reduce land value.

Based on past land use we know that a significant number of sites in Canterbury region pose risks to human health and the environment. Environment Canterbury aims to identify and record these sites (on our database) so that they can be safely managed.

Several national guidelines for contaminated land have been published or are being prepared by the Ministry for the Environment. We recommend that these are used when investigating, managing or remediating sites. Visit the New Zealand Ministry for the Environment website  for further details on the guidelines.

Managing contaminated land can be complex. Currently there is no comprehensive national policy to co-ordinate the identification, assessment and management of contaminated land. Therefore, a co-operative approach involving all parties and factors is considered to be the most practical way of managing sites and accomplishing any remediation work. Environment Canterbury would like to see stronger national policy to enable more effective management of contaminated sites in the future.

How can I prevent contamination in the future?

Hazardous substances and hazardous wastes need to be carefully managed to prevent contamination.

We can minimise the effects of hazardous substances in our environment by:

• only using hazardous substances when absolutely necessary
• applying safe practice when using and storing hazardous substances
• transporting hazardous substances safely
• disposing of hazardous substances correctly. Visit the waste section for details about managing hazardous wastes.