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 Hazardous Activities and Industries List (HAIL), that site is added to Council's Listed Land Use 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 Listed Land Use Register. The register may not, however, capture earlier land uses or activities were records were less reliable, so Council is undertaking a systematic review of historical aerial photos and other information sources in its possession which may be indicative of the presence of contaminates.
Source, pathway, receptor exposure model (source ECAN) can indicate risk.
- 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 be 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 Listed Land Use 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:
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.