Remediation of Contaminated Sites

Remediation or management of sites

In situations where a site has been adequately investigated, and found to contain contaminants above environmental acceptance values, further work is required to address the contamination.

Risks associated with contaminated sites can be managed by breaking the source-pathway-receptor chain. The source-pathway-receptor chain is illustrated in the diagram below.

source-receptors-pathway model illustration

The source-pathway-receptor chain can be broken by:

Removing the source of contamination (remediation).
Removing the exposure pathways that allow contaminants to reach receptors (management).
Removing the receptors (management).

The first approach implies a cleanup of a contaminated site (remediation), while the second and third approaches use engineering or changes in behaviour or activities to reduce or remove risk.

All possible options, along with the chosen approach taken should be documented in a Remedial Action Plan (RAP) that explains why the approach was chosen. Remedial work should be documented in a Site Validation Report, so that future parties can identify the work undertaken.

Contaminated Sites Remediation Fund (CSRF)

Funding from the New Zealand Government is available to assist regional councils in the investigation and remediation of certain contaminated sites. To qualify, the sites must pose a known or potential risk to human health and/or the environment within their regions. Contaminated sites that would qualify for funding under the CSRF are those that are located in environmentally or culturally sensitive areas, where the landowner has the will but not the financial resources to undertake the work themselves.

The New Zealand government has made available up to $2 million per year for the CSRF since 2003. The funding has been made available in two parts; $1 million per year is allocated to the clean up of New Zealand’s highest risk contaminated sites (e.g Mapua). $1 million per year is available as a contestable fund to assist regional councils in the investigation and clean up of high risk sites. (Source MfE (2006) Working Towards a Comprehensive Policy Framework for Managing Contaminated Land in New Zealand Leaving Environment Canterbury ). The budget announcement in May 2006 allocated an extra $1.7 million per year to the fund for the next 3 years (2006-2007). Find out more by visiting the MfE website .

Since 2003 the fund has supported 33 projects throughout New Zealand. Of these projects, 26 have been for assessment and remediation planning rather than actual remediation. A number of sites in the Canterbury Region have benefited from CSRF funding. These include the Sandilands historic landfill area in Christchurch, an abandoned spray contractors yard and an area of Lyttelton Inner Harbour Seabed.

How can I prevent contamination in the future?

The use, storage and transportation of hazardous substances and hazardous wastes need to be carefully managed in order to prevent contamination.

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

only using hazardous substances when absolutely necessary
employing 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.

Safe Storage of Hazardous Substances:

Safe Storage