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Working Towards a Comprehensive Policy Framework for Managing Contaminated Land in New Zealand

Acknowledgements

Executive Summary

1 Introduction

2 Existing Measures

3 Opportunities for Change

4 Next Steps

Appendix A: Main Contaminated Land Legislation

Appendix B: Comparison of Key Elements with Existing Measures

Appendix C: Detailed Process Diagram

Appendix D: Hierarchy of Documents Containing Guidelines Values for Soil, Surface Water, Groundwater and Sediment

Appendix E: New Zealand Guideline Values for Soil, Surface Water, Groundwater and Sediment

Appendix F: WasteTRACK

Appendix G: Section 43 of the Resource Management Act

References

3 Opportunities for Change

In its Statement of Intent 2006-2009 (Ministry for the Environment, 2006e), the Ministry signalled an ongoing commitment to developing policy for contaminated land; in particular, to “confirm a comprehensive policy framework for managing contaminated land, including national environmental standards”.  A number of opportunities are available to the Ministry to deliver on this commitment, and these are discussed below.

3.1 Elements of a contaminated land policy framework

To help identify and prioritise these opportunities, we outline the ideal key elements of a contaminated land framework for New Zealand.  These were identified by referring to contaminated land policy in the United Kingdom, Europe, the US and Canada.

The key elements of a contaminated land framework in New Zealand could include:

• a legislative framework that has definitions, planning controls and a liabilityregime, and defines roles and responsibilities for agencies
• measures to prevent contamination of land
• mechanisms to identify, record, investigate, manage, remediate and report on contaminated land
• protection of humanhealth from the effects of contaminated land
• protection of the environment from the effects of contaminated land
• access to information.

These key elements would contribute towards achieving the outcomes identified in Figure 1.

3.2 Opportunities for change

Opportunities for change were identified by comparing the existing measures described in section 2 with the ideal key elements of a New Zealand contaminated land framework identified above.  A priority is assigned to each of these opportunities based on their perceived need and/or urgency.

Table 1 summarises this analysis.  Each identified opportunity is then described and discussed in the following sections.  A detailed table comparing key elements with existing measures, opportunities and their relative priority is attached in Appendix B.

Table 1: Key elements of a New Zealand contaminated land framework, opportunities for change, and their priority

View key elements of a New Zealand contaminated land framework, opportunities for change, and their priority (large table).

A nationally consistent method to derive soil guideline values

Numerical values for hazardous substances that are protective of human health and the environment, and the methods used to derive them, are important tools in the assessment of contaminated land.  Without these values and methods we would not be able to consistently assess the effect of contaminated land on the environment or on human health.

Typically, New Zealand practitioners have relied on a mixture of national and international guidelines from which to select numerical values for decision-making.  However, these guidelines use different methods for deriving numerical values.  Although CLMG No. 2 has helped practitioners select appropriate values from this mix, it remains unclear which guideline value to choose for a given assessment, or how a value should be applied to the investigation or management of land.  In addition, calculation errors contained in some of the guideline values (eg, timber treatment, oil industry) and inconsistencies between guidelines (eg, gasworks, oil industry), have remained uncorrected and are often still used in assessments.

These issues have contributed to uncertainty for practitioners and local government when investigating, identifying, preventing or mitigating the adverse effects of the development, subdivision or use of contaminated land.  Problems arising from this uncertainty have most notably occurred in Auckland, with the residential subdivision of former horticultural areas.

An overarching national guideline that sets out a method to derive numerical values for key soil contaminants and how they can be applied to decision-making to protect human health and ecosystems will significantly improve decision-making on contaminated land in New Zealand.  The process for developing a guideline, and a component of the guideline, may also be suitable for being applied to the development of a national environmental standard.

The rationale for national health-based guidelines

National guidelines have been the main mechanism used by central government to guide and support contaminated land practitioners in industry and local government.  The development of an overarching national guideline for contaminated land that consolidates key soil guideline values for the assessment of contaminated land into one document is likely, in itself, to significantly improve contaminated land management.  A national guideline would help improve practice by:

• providing a one-stop reference for practitioners on the derivation and use of health-based numerical values
• reducing confusion about what method or value to use, and in what circumstances
• containing numerical values protective of land uses tailored to the New Zealand setting (eg, a lifestyle block)
• increasing consistency in how land is assessed and managed.

Such a guideline should be developed in collaboration with the other relevant government regulatory agencies (Ministry of Health, Ministry of Agriculture and Forestry, ERMA, NZFSA), with specialist advice from local government and industry representatives.  The methodologies, receptors, land uses and terminology used should be agreed by these agencies to provide the highest level of endorsement and uptake of the guidelines.

Guidelines, however, are voluntary and local governments are not required to implement them.  Although credible guidelines are widely implemented by local government and practitioners, it is unusual for all councils and practitioners to fully subscribe to their contents.  Also, the transition time between publishing a guideline and that guideline being widely used may be lengthy.  Plans that reference previous guidelines would need to be changed for the guidelines to have full effect in those areas.  As an example of the sometime lengthy transition period, of the 18 district plans that contain specific contaminated land rules, 13 still reference the Australian and New Zealand Guidelines for the Assessment and Management of Contaminated Sites (ANZECC, 1992), which has been largely outdated for over six years (Ministry for the Environment, 2006c).

An overarching national guideline could also complement and create a platform for the development of a national environmental standard (NES) for contaminated land.  Ideally, the development of a national guideline would form the first step of any process to develop a NES for contaminated land.

The rationale for national environmental standards

National environmental standards are regulations made under sections 43 and 44 of the RMA.  Standards can be numerical values, narrative statements, or methodologies in a legally enforceable form.

A NES that provides a method and/or numerical values for soil contaminants would ensure the immediate and consistent use of those methods or values.  The key benefits of a NES approach over a national guideline are that a NES:

• overwrites conflicting guidelines and local government plans, avoiding the transition normally associated with the implementation of guidelines
• is considered suitable for setting human-health thresholds, where consistency and certainty are desirable
• ensures that any methods or values it contains are implemented because any requirements are binding on local government.

However, these benefits need to be balanced against any loss of flexibility that can be provided through a guideline-based approach.  Some numerical values derived in a national guideline may not suit a NES.  For example, soil contaminant values derived for the protection of groundwater may be suitable in a guideline but inappropriate for a NES.

A NES for contaminated land would need to be developed in collaboration with the other relevant government regulatory agencies (Ministry of Health, Ministry of Agriculture and Forestry, ERMA and NZFSA), with technical advice from local government and industry representatives.  These agencies would need to agree on the functional application of numerical values and methods.

A method-based NES could be used to define what method is to be used to derive numerical values.  This method could then be used to derive site-specific numerical values which would assist in the management of a piece of contaminated land (tier 2 assessment).  A method-based NES could stand alone or work together with a numerical-value NES.

A numerical value-based NES could be used to:

• help define contaminated land according to its definition under the RMA [If a NES is developed for contaminants in soil, the NES soil levels are unlikely to be the sole determinant of whether land is “contaminated”. Where contaminants are not listed in the NES, or if ecological levels are not included, the existing mix of guidelines would need to continue to be used to establish whether the land “has, or is reasonably likely to have, significant adverse effects on the environment”.]
• establish the suitability of land for its intended land use
• act as a remediation or clean-up target
• trigger further investigation, management or remediation.

It is unlikely that numerical values would serve as an absolute remediation requirement (ie, a level that all contaminated land would have to achieve).  It is envisaged that risk-based methods would still be able to be used to derive site-specific values, especially where clean-up is not justified or practical.

The agencies would also need to agree on what methodology to use.  During previous scoping on possible NES two main options were identified[Note that these and other methodologies would be revisited and reassessed by any future advisory group.].

• A New Zealand-specific NES: New Zealand-specific methods could be used to derive soil contaminant levels (eg, the Landcare risk assessment method for contaminated sites).  The NES could be based on a national list of priority contaminants developed in consultation with key stakeholders.  This option has received widespread support from previous technical and policy stakeholder groups.
• NES based on the Australian National Environment Protection (Assessment of Site Contamination) Measure (NEPM): adoption of the NEPM soil limits for human health and the environment would have the benefit of more closely aligning Australian and New Zealand contaminated land policy.  The adoption of NEPM numbers was discussed during October 2006, but was not supported by local government and industry.

Once an option is agreed, we would need to decide whether the NES should include both human health and ecological soil methods and numerical values.  It may be more practical to develop health-based soil values first, leaving the option for ecological soil values to be added.  Human health-based soil levels are relatively straightforward to derive because there is only one target species (humans), and large databases from epidemiological and toxicological studies worldwide can be accessed.  Ecological soil levels are much less straightforward due to a number of technical and policy-related issues.

Develop a roles and responsibilities protocol

Although the roles and responsibilities of local government have been clarified by recent amendments to the RMA, there is still uncertainty as to how the main agencies (territorial authorities, regional councils, public health agencies) should work together on a day-to-day basis.  This uncertainty may lead to disputes between agencies, and roles and responsibilities not being filled or undertaken.

To clarify roles and responsibilities relating to contaminated land, the Ministry for the Environment could by developing guidance for how local government can best fulfil their respective functions.  This guidance could build upon the new RMA contaminated land functions by:

• providing recommended roles regional councils, territorial authorities, unitary authorities health agencies and potentially landowners will have at the key decision points (e.g. identification, investigations, remediation, management, etc) 
• identifying and describing best practice for these roles.

Any guidance would be developed in consultation with local government and public health, and would recognise existing practice and successful alternative roles and responsibility frameworks.

Tracking contaminated soil and wastes

Where contaminated land is disturbed and contaminated soil or waste is disposed off-site it is important this material is safely transported to an approved disposal or treatment facility.  The inappropriate off-site disposal of contaminated soil and waste can simply result in the creation of more contaminated land.

An online tracking system, WasteTRACK, is being adopted by liquid waste contractors through their industry code of practice and is progressively being required through amendments to territorial authority trade waste bylaws.  The liquid waste contractors have already seen the benefits of using WasteTRACK, such as improving business practices, tracking seasonal variations in waste generation, and planning business workloads and maintenance.

Although WasteTRACK is only being used for the liquid waste industry, it is planned to require this system for the transport of all hazardous waste, including solid hazardous waste.  This should include the transport of soil or waste from contaminated land.  The most appropriate mechanism for requiring WasteTRACK nationally has been identified as group standards under the HSNO Act.  The Ministry is currently preparing to draft group standards for hazardous waste with industry.

Further information on WasteTRACK is attached in Appendix F and on the WasteTRACK website [www.wastetrack.co.nz].

New guidelines and revising existing guidelines

There are many existing contaminated land guidelines (see section 2).  To remain credible and useful to practitioners, these guidelines need to be regularly revisited and, if necessary, revised as more information becomes available or as policy changes.  There are also opportunities for new guidelines to fill gaps in the policy framework.

The Ministry can continue to develop further guidelines on specific types of contamination.  The sheep-dip guidelines have recently been completed.  In addition, our stakeholders have suggested a number of other possibilities for further guidance, including:

• roles and responsibilities (see section above)
• clean-up technologies and methods
• remediation by natural attenuation
• horticultural guidelines.

If a NES or overarching national guideline were to be developed, the existing industry guidelines would also need to be reviewed.  This review could be as simple as pulling conflicting numerical values and derivation details out of the documents while maintaining the useful generic and industry-specific sections [This review may be more complex for the oil industry guidelines because the numerical values depend on soil type.].

Support could also be provided for industry groups who wish to revise existing guidance. Representatives from the oil industry have signalled to the Ministry that they would like to review the Guidelines for Assessing and Managing Petroleum Hydrocarbon Contaminated Sites in New Zealand, one of the most widely used industry-based guidelines.

Liability regime

Liability is managed under the RMA by the requirement to avoid, remedy or mitigate any adverse effects on the environment.  However, there is no clear liability for pre-1991 sites.  Generally, in these cases, the buyer of the land becomes liable by default for any contamination present on the land (caveat emptor, or buyer beware).  The degree to which this issue is posing a barrier to the clean-up of contaminated land is unclear, although feedback from local government suggests that it does pose a barrier in some situations.

The Ministry can work with central government agencies to investigate an appropriate pre-1991 liability regime for contaminated land.  Liability regimes that could be applied include:

• the owner/occupier is liable
• a hierarchy of liable parties (from polluter to owner/occupier) [International examples of hierarchical liability regimes are found in: the UK - see www.defra.gov.uk and search for Defra Circular 01/2006 (Defra, 2006) and NSW, Australia - see www.environment.nsw.gov.au/clm/index.htm]
• no hierarchy.

If establishing a liability regime is not favoured, the Contaminated Sites Remediation Fund should be specifically identified as the mechanism to deal with any equity and liability barriers to clean-up created by not having a liability regime.  Modifications may need to be made to the Fund to specifically address these barriers.

Before any liability regime is investigated it is important to clearly establish the degree to which this issue is posing a barrier to the clean-up of contaminated land.  The collection of national information on contaminated land, as discussed below, would enable a more informed investigation and recommendations to Government.

Contaminated Sites Remediation Fund

The Contaminated Sites Remediation Fund continues to be a successful policy initiative directly contributing to real on-the-ground actions.  However, its success is limited by the Fund’s size.  Although the Fund has been successful and has recently been expanded, it is still not large enough to provide the assistance needed for many large-scale clean-up projects.

Accreditation of practitioners

There is no requirement for contaminated land practitioners, or most other environmental specialists in New Zealand for that matter, to be accredited, nor is there a specific contaminated land accreditation system.

The existing suite of industry-based guidelines and the Contaminated Land Management Guidelines series have established a benchmark for contaminated land practitioners and a basis for local government audit of investigations (especially CLMG No. 1).  However, a requirement for practitioners to be accredited may introduce an additional level of consistency and quality assurance to contaminated land investigations.  Accreditation systems are used extensively internationally; for example, several accreditation schemes are running in Australia, which require review of investigations by accredited auditors[New South Wales (www.environment.nsw.gov.au/clm/auditorscheme.htm); Victoria, South Australia (http://www.epa.sa.gov.au/pdfs/expl_ep_site.pdf) and Western Australia.].

However, before any accreditation system is established its benefits would need to be assessed against the additional costs of set-up, administration and liability insurance, and the barriers these increased costs could add to the investigation and clean-up of land.

Providing training

Local governments often do not have the capability to discharge their responsibilities for contaminated land under the RMA effectively, and this lack is presenting a barrier to the identification, investigation, management and remediation of contaminated land.  To improve the capability of local government in this area, the Ministry could contribute to improving the competence of staff through training.  Initiatives might include:

• providing training directly
• better linking existing training providers with local authority officers and private sector practitioners
• encouraging, or even assisting, local government to provide training to staff working with contaminated land.

National information

At a national level, we do not have a clear understanding of the extent of contaminated land requiring management or remediation.  A 1992 desktop assessment of the number of contaminated sites estimated (with a ±50 percent margin of error) that there were 7,200 land-use sites (sites with potentially contaminating land uses).  Approximately 1,580 sites were high-risk contaminated land (Worley Consultants Ltd, 1992).  Since then, work by regional councils has established that there are many more than 7,200 sites with historical or current land uses with the potential to contaminate, but it is unclear how many of these might present a high risk.

The Ministry could collect national information on contaminated land.  It is envisaged this would involve collecting summary data from existing local government registers.  National information would not contain property-specific information, but would be a national overview only.  The collection and administration of property-specific information would remain with local government.

National information would provide a useful overall picture of the state of contaminated land, enabling:

• better prioritisation of actions (eg, identifying priority sites for funding)
• national reporting on the effectiveness of contaminated land policy (eg, periodically assessing changes in the number and severity of contaminated sites, or land that has been investigated, managed and remediated)
• improved policy development (eg, information on numbers of pre-1991 contaminated sites would be useful to tailor options for liability regimes or modify other policy measures such as the CSRF).

However, national information is only as good as the local information that is available, and the collection of accurate local information about contaminants on land is hampered by several factors, including the following:

• councils use different systems to classify information about land or potentially contaminated land, which significantly complicates collecting national information
• councils put varying levels of effort into identifying contaminated or potentially contaminated land, which can result in a wide unexplained variance between regions of the number of contaminated sites
• councils may apply different thresholds to define contaminated land
• landowners/occupiers are not compelled to report land contamination to councils.  This is especially an issue for establishing the location of historical sheep-dip sites, where there are large numbers of sites and a decreasing awareness of their exact locations as the original landowners/occupiers sell or retire
• the lack of expertise by some contaminated land investigators, inconsistent standards of site assessment and the lack of consistency in reporting mean that a site may not be correctly identified as contaminated, or may be identified as presenting more risk than it really does.

CLMG No. 4 Classification and Information Management Protocols (Ministry for the Environment, 2006b) may partially address some of these barriers by promoting best practice among local authorities for identifying and classifying sites.  If this guideline is widely implemented by local authorities, and supported by a model contaminated land information database [A contaminated land information management database is a database that contains and sorts information about contamination on land within a region or a district. It is envisaged that a database supporting CLMG No. 4 could be developed by adopting and/or modifying an existing database.], the periodic national collation of data on contaminated sites should be a relatively simple task.  CLMG No. 1 Reporting on Contaminated Sites in New Zealand (Ministry for the Environment, 2003a)and CLMG No. 5 Site Investigation and Analysis of Soils (Ministry for the Environment, 2004b)have tried to address some of the investigation and reporting issues, although uptake has been variable among territorial authorities and practitioners.

Therefore, before any information is collated the Ministry should first concentrate efforts on encouraging and supporting local government implementation of CLMG No. 4.  While not addressing all of the barriers to the collection of accurate information, the widespread adoption of this guideline and the use of a supporting information management database are considered important first steps towards collecting accurate information about contaminants on land.

Other national environmental standards

This paper discusses the possibility of a NES being used to set numerical values for soil contaminants and methods to derive these values.  However, the RMA enables standards to be applied in a range of other ways, and there needs to be further discussion and debate about the potential for a NES to be applied to other contaminated land issues.  For example, a NES could be used to introduce a level of consistency to district plan requirements.

To enable readers to explore these possibilities with a view to discussing or suggesting other ways a NES could be applied to contaminated land management, we have included the following suggestions and links.  Section 43 of the RMA (see Appendix G) sets out what a NES can include.

The following examples show how NES have been, or are proposed to be, used[Note that standards are not limited to these types.]:

• prohibit specified activities
• require consents for specified activities
• restrict the granting of resource consents
• restrict the setting of permitted activities
• in design standards
• require monitoring and reporting by councils.

Examples of these types of standards can be found on the Ministry’s NES web pages[www.mfe.govt.nz/laws/standards/index.html].

Emerging issues and research

The work on an overarching policy framework and the development of many of the opportunities identified above can be informed by other emerging initiatives.  For example:

• a national working group on levels of cadmium in soils from fertiliser use has been established to advise government
• Environment Waikato recently convened a workshop of scientists, regulatory staff and policy advisers to discuss polycyclic aromatic hydrocarbons in urban areas of New Zealand.

Further research can be co-ordinated to fill information gaps in necessary areas.