top of page

Contamination and soils- What impact does it have on subdivision?

Updated: Jun 29, 2023

You may have seen our recent blogs in our rural subdivision series (if not, you can access them here). Once you know the “basis” of your subdivision (resource consent) application, which could be bush or wetland protection, or revegetation, you can start looking at other specific characteristics, features or constraints on your site. One of these is potential contamination, and this relates to current and past land uses. The National Environmental Standard for Assessing and Managing Contaminants in Soil to Protect Human Health (usually shortened NES(CS) or NES(Soil)) is relevant in relation to this.

What is the NES(CS)?

Some past land uses using hazardous substances in industry, agriculture and horticulture activities can leave soil contamination. This is a problem when the contamination is at a concentration and in a place where it has, or is reasonably likely to have, an adverse impact on human health or the environment. This could include in cases where food is grown, where people live, close to water bodies or important habitats. The NES(CS) provides a nationally consistent method of identifying and remediating contaminated land. The NES(CS) sits above district and regional plans in terms of the planning hierarchy, and its requirements are relevant all-over New Zealand.

The NES(CS) aims to ensure that land affected by contaminants is identified prior to development, which can include earthworks, and is remediated or the contaminants contained to make the land safe for human use.

How does the NES(CS) affect subdivision?

In general terms, the NES(CS) applies when you are:

  • Removing or replacing a fuel storage system;

  • Sampling soil to determine whether it is contaminated;

  • Disturbing the soil;

  • Subdividing land;

  • Changing the use of the piece of land in certain circumstances.

Specific provisions are present in relation to production land, and we recommend you seek further advice in relation to this.

Subdivision triggers the NES(CS) and you will need to confirm if a hazardous activity has been undertaken on the “piece of land” (as referred to in the NES(CS)). A “piece of land” is not the legal property boundary of the site but rather the area impacted by the activity.

The relevant contamination or hazardous activities are detailed in the Ministry for the Environments Hazardous Activities and Industries List (“HAIL list”). This list is the first step in investigating potential contamination of a site, so is quite a broad list, and it includes present and past land uses. You can investigate past land uses by reviewing the sites property file and other records at your local Council, historical aerial photos, speaking to previous owners and by soil sampling and analysis. You can also understand past land uses through old buildings, concrete platforms etc that may still be on the site. This is something a professional can assist you with also.

What’s the first step if a HAIL activity is/ was present?

If a HAIL activity is/ was present on the piece of land, you will need to undertake a Preliminary Site Investigation (“PSI”). This is undertaken by a Suitably Qualified and Experienced Practitioner (called a “SQEP”)- you must choose this person carefully because if you don’t choose someone suitable, the Council will not accept the PSI. There are many professionals who specialise in contamination; get in contact if you would like a recommendation.

If the PSI can demonstrate that the site activities were unlikely to have resulted in contamination, further investigation may not be required. This could relate for example, to the horticulture practises that were in place at the time or potentially existing certification that the activity was organically operated. If this cannot be demonstrated, a Detailed Site Investigation (DSI) and likely resource consent will be needed.

Detailed Site Investigation (DSI)

A DSI will undertake further investigations of the site, including taking soil samples for testing and analysis, and confirm if the site is safe for the proposed use and what, if any, remedial actions are required. This will be assessed by the Council as part of a resource consent application, usually bundled in with your subdivision consent application (or any other resource consent type if you’re not subdividing). In terms of subdivision, you will usually be required to undertake the remedial works before you can get section 224(c) RMA certification (you can find out more about the subdivision process here).

Need more advice?

While we don’t have in- house contamination specialists, we do work with professionals who have these skills and experience and are recognised SQEP’s. If you have a subdivision in mind, get in contact and we can recommend a specialist from our network who we feel will work well with you and has experience in your type of development. You can contact us on

Hannah Thomson is Director of Planning Plusand has over 20 years of resource management experience working in both local government and the private sector. This includes five years at Rodney District Council in roles including Senior Planner and Team Leader. Hannah has a wide range of experience including commercial, rural, residential and coastal development and subdivision on small to large scales and appearances at both Council and Environment Court as an expert witness for mediation and hearings. Hannah has assisted Councils with policy development and has also assisted private individuals with submissions to Council.

​Hannah holds the qualifications of BSc (Environmental Science) and Masters of Applied Science (Environmental Management), is a Member (Int) of the New Zealand Planning Institute and Secretary of the New Zealand Planning Institute Auckland Branch Committee. Hannah is also a member of the Resource Management Law Association.


As with all our blogs this information is preliminary in nature only and correct at the time of writing. It is not intended to substitute for your own investigations or obtaining specific advice on your proposal from professionals. Planning Plus LtdTM is not liable in any way for any errors or omissions. © Planning Plus Ltd 2023

Recent Posts

See All


bottom of page