The Resource Management Act 1991 (RMA) is the primary piece of environmental legislation used to control the effects of the use of contaminated land on the environment and people. The RMA also outlines the roles and responsibility of local government. Because the Marlborough District Council is a unitary authority we have both regional and territorial functions and responsibilities under section 15, 30 and 31 of the RMA which include:
- Control of discharges to the environment, such as discharges from a contaminated site to soil, air, groundwater or surface water
- Investigation of land for the purpose of identifying and monitoring contaminated land
- Prevention or mitigation of any adverse effects of the development, subdivision, or use of contaminated land
How Does the Council Manage Information about Contaminated sites?
Once a site has been identified as contaminated or has been used for an activity or industry listed on the HAIL, that site is added to Council's Sites at Risk Register. The register is an electronic database used to manage information about sites within the region. After the site is added to the register it is investigated and assigned into one of six categories.
The information stored on the register is useful for a range of organisations including central government, environmental consultancies and is used by Council in response to Land Information Memorandum (LIM) and Project Information Memorandum (PIM) requests. This ensures that prospective purchasers of existing properties are aware of the potential presence of contaminants on a site.
What Are the Risks Associated with Contaminated Sites?
Council is currently identifying and adding sites to the Sites at Risk Register. The risk posed by individual sites is then assessed using the New Zealand Ministry for the Environment's Risk Screening System. The RSS provides a nationally consistent means of ranking sites that are, or are suspected of being, contaminated as being of high, medium or low risk and prioritising them for investigation. The ranking of sites is based on the source-pathway-receptor model.
Source, pathway, receptor exposure model (source ECAN)
- Source – presence of a significant source of contamination
- Pathways – through which contamination moves from the source to the receptors
- Receptors – the plants, animals and/or people which may be adversely affected by the contamination
It is only when the source, pathway and receptor chain is complete that a risk actually exists.
Minimising the Risk of Contaminated Sites
Risks associated with contaminated sites can minimised by breaking the source-pathway-receptor chain. This can be achieved by either:
- Removing the source of the contamination eg; remediation
- Removing the pathway that allow contaminants to impact on a receptor eg; capping the site
- Removing the receptor eg; fence out animals
Information for Property Buyers
Over time information recorded on the Sites at Risk Register will be transferred onto Land Information Memoranda (LIM) and Project Information Memoranda (PIM) issued by Council. In addition, a series of four brochures are available on the topics of what you need to know when:
Contaminated Land - Buying a property (789 Kb)
Contaminated Land - Selling a property (783 Kb)
Contaminated Land - Conveyancing a property (788 Kb)
Contaminated Land - Valuing a property (778 Kb)
Information includes why contamination is a problem, how to find out if land is contaminated, who is responsible for a contaminated site, and the unitary council role in contaminated land as well as advice for prospective buyers, sellers, lawyers and valuers.