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Hazardous Substance Strategy: Volume Two

Executive Summary

1 Introduction

2 Environmental and Tolerable Exposure Limits

3 Research on Hazardous Substances

4 Substances Imported for Export Only

5 Improving Compliance Monitoring and Enforcement

6 Data Protection Issues

7 New Pathways

8 Regulatory Impact Statement - Data Collection

9 Having Your Say

10 Glossary

Appendix 1: How Environmental and Tolerable Exposure Limits are Set

Appendix 2: Issues with the Exempt Laboratories Regulations

2 Environmental and Tolerable Exposure Limits

Several problems have been identified with exposure limit controls under the HSNO Act for ecotoxic and toxic substances. In particular, there are concerns that these controls conflict with established methods for setting environmental concentration limits and that they will be very difficult to enforce.

The Hazardous Substances and New Organisms (Transitional Provisions and Controls) Amendment Act came into force on 24 March 2004. One of the outcomes of these amendments is to allow ERMA the flexibility not to set a control for a substance, provided certain criteria are met. The advantage is that environmental and tolerable exposure limits do not have to be set for substances where the setting such limits is not an effective or cost-effective means of controlling the effects of the substance.

In addition to the above Act amendment, the Ministry for the Environment has released a discussion paper concerning regulation amendments for pesticides transfer. [Ministry for the Environment,Proposed Regulation Amendments for Pesticides Transfer and Other Matters, Ministry for the Environment, Wellington, 2004.] The paper proposes a number of amendments to the Hazardous Substances (Classes 6, 8, 9 Controls) Regulations 2001 that we consider would substantially improve the setting and workability of environmental and tolerable exposure limits.

In general, the proposed regulation amendments involve the removal of a number of the technical constraints currently in the regulations, in order to enable ERMA additional flexibility to:

• set a range of environmental and tolerable exposure limits (eg, for fresh water, a range of environmental limits can be set for different pHs)
• consider best international practice (in a prescribed manner) for the assessment of toxicological and ecotoxicological data when setting environmental and tolerable exposure limits
• where there is a lack of sufficient national data, adopt international values as environmental and tolerable exposure limits.

The proposed changes to regulations are due to be in force before 1 July 2004.

Both the HSNO Amendment Act and the proposed regulation amendments will improve the workability of the environmental exposure limit (EEL) and tolerable exposure limit (TEL) controls. However, there are some issues that these changes do not address, particularly around compliance and enforcement. These issues are discussed further below.

ERMA is in the process of consulting on controls for toxic and ecotoxic substances, in preparation for the transfer of pesticides scheduled for July 2004. Most of these substances trigger exposure limit controls. However, given the difficulty with their effectiveness, ERMA is presently proposing not to set EELs and TELs until the issues described below have been resolved.

2.1 The purpose and benefits of environmental and tolerable exposure limits

The purpose of setting environmental and tolerable exposure limits is to establish safe levels of a substance that can be intentionally released into the environment, in order to protect people and the environment from any adverse effects.

EELs are intended to help manage the effects of ecotoxic substances on the environment. An EEL establishes the maximum concentration of an ecotoxic substance legally allowable in a particular environmental medium (eg, water, soil or sediment), and/or a maximum loading of a substance onto a surface (eg, as in spray drift deposition). They are currently single-value concentration or loading limits set for environmental media (water, soil, sediment and surface deposition) after reasonable mixing, outside the target area, or for organisms exposed to ecotoxic substances by secondary poisoning. The process for setting EELs is described in the Hazardous Substances (Classes 6, 8, and 9 Controls) Regulations 2001, and in Appendix 1 of this document.

TELs are controls set by ERMA to help manage the effects of toxic substances on human health. They are single-value concentration limits set for exposure sources to humans (eg, air, water, soil, surface deposition). The process for setting TELs is described in the Hazardous Substances (Classes 6, 8, and 9 Controls) Regulations 2001, and in Appendix 1 of this document.

Apart from providing a measure of safety for people and the environment from activities where hazardous substances are intentionally released or applied into the environment, there is another key benefit of the EELs and TELs approach. Environmental and tolerable exposure limit controls are performance requirements, rather than prescriptive statements of how you should manage ecotoxic or toxic substances. For example, an EEL set for water for pesticide x does not state that x cannot be sprayed aerially or cannot be used in certain weather conditions. However, a person using pesticide x must not exceed the EEL outside the target spray area at any time. The person using x also has to consider their spray method and satisfy themselves that they will keep to the EEL. The advantage of performance-based requirements such as TELs and EELs is that they allow users maximum flexibility as to the manner in which they carry out the task at hand.

2.2 Issues with environmental and tolerable exposure limits

There are four key issues for the workability of environmental and tolerable exposure limits:

1. reconciling the EELs 'pass/fail' approach with the usual risk management approach to environmental limits
2. demonstrating compliance or enforcing exposure limits when multiple sources of the same substance are present in one environment
3. demonstrating compliance or enforcing exposure limits when they are difficult to measure
4. consulting with all affected people when a component occurs in many different substances.

Each issue is discussed in more detail below.

2.2.1 Issue 1: Reconciling the EELs 'pass/fail' approach with the usual risk management approach to environmental limits

EELs are set as a single value that you are either above or below - in other words, pass or fail. This pass/fail approach of the HSNO Act is inconsistent with the site-specific 'trigger value' approach of ANZECC and other international applications of these kinds of values.

If the EEL is exceeded then the offender could be prosecuted - even though it is possible that the receiving environment is suffering no adverse effects from the presence of the hazardous substance. The converse is also possible. The general practice in the environmental field is to take a risk management approach where, if a trigger value is exceeded, then further work is required to determine whether adverse environmental effects are occurring or not.

The HSNO Act does not provide for enforcement agencies or regional councils to take into account the characteristics of the receiving environment. Councils may set more stringent values than the EEL, but they cannot set less stringent ones, even though specific site characteristic may warrant this (eg, high natural background concentrations to which the flora and fauna have adapted, or where the natural background levels are higher than the EEL). This is clearly contrary to the effects-based approach of the RMA.

The HSNO Act pass/fail approach will be in conflict with any risk management-based guidelines. Indeed, the Ministry for the Environment has been involved in developing a number of guidelines that could potentially be in conflict with HSNO environmental exposure limits, including:

• Health and Environmental Guidelines for Selected Timber Treatment Chemicals (Ministry for the Environment, 1997)
• Guidelines for Assessing and Managing Petroleum Hydrocarbon Contaminated Sites in New Zealand (Ministry for the Environment, 1998)
• New Zealand Municipal Wastewater Monitoring Guidelines (New Zealand Water and Environmental Research Foundation, 2002).

2.2.2 Issue 2: Demonstrating compliance or enforcing exposure limits when multiple sources of the same substance are present

The HSNO approach to environmental limits does not deal well with multiple sources of hazardous substances being released into the same environment. Sources of hazardous substances range from industrial activities to storm-water discharge. For example, there could be 10 people spraying the same substance in a catchment - who is responsible for exceeding the EEL if the substance is detected in the local stream?

It is worth noting that this issue is common to all approaches that involve setting exposure limits. Australian and New Zealand Environment and Conservation Council (ANZECC) guidelines, the guidelines commonly used in New Zealand for environmental limits, do not deal with this issue in setting trigger values.

2.2.3 Issue 3: The difficulty of measuring environmental and tolerable exposure limits in the environment

There is a significant issue with measuring environmental and tolerable exposure limits that are close to or well below analytical limits of detection. This problem also applies to many international exposure limits, which are very small. While non-compliance will be measurable, it will be difficult for people to demonstrate compliance with a concentration which cannot be reliably measured.

There is also a misconception that analytical methods will be capable of reaching much lower in the future than at present. In fact many instrumental methods are at or near their theoretical limits already. Issues also arise from an increased probability of sample contamination representing a larger part of the measurement as the measured number gets lower.

Even for higher measurable concentrations, different analytical and sampling methods can produce different results for the same samples. The timing of sampling can also be critical for some substances because they degrade very rapidly within or on plant tissues or soil and they may not leave characteristic residues. This makes demonstrating compliance or catching non-compliance very difficult. In addition, commercial laboratories measure concentrations, but none currently offer surface loading estimates.

2.2.4 Issue 4: Consulting with all affected people when a component occurs in many different substances

The process for setting EELs and TELs is tied to the approval of the first substance containing the particular compound or element (eg, ammonia or copper). It is difficult to consult all those who could be affected by the setting of an environmental or tolerable exposure limit for a compound or element that may be present in other substances. Also, the time requirements in the Act make it difficult for ERMA to delay consultation for the purposes of involving industry or councils.

2.3 Options for improving the workability of environmental and tolerable exposure limits

We propose a combination of approaches to address the issues with EELs and TELs we have been discussing. Table 1 below sets out the issues we are seeking to address (across the top) and the options for consideration (down the side). We then go on to discuss each option in detail.

Table 1: Options and issues for environmental and tolerable exposure limits

View options and issues for environmental and tolerable exposure limites (large table)

2.3.1 Option A: Only set EELs for substances intentionally discharged into the environment

This option helps to address issues 1 and 2 by not setting EELs for some substances. For example, EELs are important and necessary controls for pesticides, but not important to manage the effects of paints.

This option could be implemented by developing an ERMA policy on which substances need EELs. However, in order not to set an EEL, ERMA would still need to satisfy the criteria set out in the Act. [See section 160B, Hazardous Substances and New Organisms (Transitional Provisions and Controls) Amendment Act, enacted on 23 March 2004.]

Taking this option would require the Hazardous Substances Disposal Regulations 2001 to be reconsidered. Currently, if an EEL exists for a substance then you can dispose of it into the environment provided the EEL is not exceeded. If an EEL is not set for a large group of substances, then you could not dispose of those substances by slow release into the environment. The implications of this need further consideration.

2.3.2 Option B: Only set environmental and/or tolerable exposure limits if the effects are not being managed by the RMA

As with option A, option B helps to address issues 1 and 2. Again this option could be implemented by developing an ERMA policy paper on which substances need an EEL, meeting the appropriate criteria set out in the Act. [See section 77A(4), Hazardous Substances and New Organisms (Transitional Provisions and Controls) Amendment Act, enacted on 23 March 2004.]

Unless permitted by a regional plan, discharges of substances into the environment require a discharge permit (a type of resource consent). During the permitting process, councils consider the effects that a discharge could have on the receiving environment, which allows councils to take into account background levels of the substance. This is something that environmental and tolerable exposure limits set at a national level cannot do.

Many regional plans contain standards or limits for substances (or 'contaminants' in RMA language) in the environment. The Ministry for the Environment is also in the process of developing national standards for some contaminants. In the absence of a national standard, ERMA would need to assess whether regional planning mechanisms are in place to manage the effects of particular substances across the whole country. Extensive consultation would be needed and it would in fact be a very difficult judgement to make.

Taking this option would require a significant change in the statutory process for handling applications due to the tight timeframes for consultation under the HSNO Act. Also, option B would only address the relatively few substances picked up by regional plans and national environment standards. Given its limited effect and difficulty in implementing, this is not a preferred option.

2.3.3 Option C: Make use of environmental and tolerable exposure limits as default values, unless a resource consent is applied for

This option addresses issue 1. Under this option an environmental or tolerable exposure limit would apply as its does now, unless a resource consent is applied for. However, a subsequent risk-based RMA-type assessment could allow for the limit to be raised, if the local environmental conditions justified such a change. This would remove the upward restriction on the resource consent-setting process (currently, a limit can be set by a resource consent that is more strict than the relevant EEL or TEL, but not less strict).

This option would:

• allow HSNO protection to be put in place for large parts of the environment not covered through the resource consenting process, and at the same time would
• allow industrial and commercial operations that are discharging a hazardous substance to proceed or continue provided they have been through the RMA resource consenting process, which is already designed to ensure protection of human and environmental health.

This option allows the RMA and the HSNO Act to neatly complement each other, and resolves the issue that EELs set at a national level may be set well below the level where a risk-based site-specific assessment shows that adverse environmental effects would occur.

While this option allows for a risk management approach, it does not address the compliance and enforcement issues for cases where environmental and tolerable exposure limits are set and so is not a solution on its own.

2.3.4 Option D: Set an environmental or tolerable exposure limit, but enforce against codes of practice only

Option D addresses the first three issues identified: 1, 2 and 3.

Under option D, environmental and tolerable exposure limits would be set, but would not be legally enforceable. However, a person using the substance would be required to follow an approved code of practice and could be prosecuted for not following it. ERMA would approve the code of practice if following the code would meet the indicated environmental or tolerable exposure limits.

This approach would improve the ability of people to know how to comply with HSNO controls to prevent adverse environmental effects. It would also make it easier to address the problems of multiple sources of a substance, where it is not possible to identify the responsible individual(s). A code of practice would set controls for how the substance is used to prevent the adverse effects. It is easier to demonstrate that a person is following or not following a best practice procedure than to capture samples of a substance in a stream, for example.

This option would require that codes of practice be developed before a substance is used. However, considerable work has already been undertaken for codes on pesticide use, for example, so for this group of substances requiring development and approval of a code would not be onerous.

Given that this option addresses three of the issues above and would be relatively straightforward to implement, we consider this a strong proposal for further consideration.

2.3.5 Option E: Set exposure limits separately from substance approvals and apply to all substances containing the particular component

Option E addresses issue 4: the problem of how to consult with all people potentially affected by a decision on an EEL for a component of a substance that occurs in other substances as well.

Separation of the environmental and tolerable exposure limit-setting process from any particular application would facilitate robust development of the values. It would, however, create difficulties for ERMA's approval process. If the substance is new, it would take some time for a generic EEL-setting process to take place. This would delay the introduction of a new substance by many months. It would also be difficult to determine who should pay for the process.

To change environmental and tolerable exposure limits to apply to all sources of a particular ecotoxic and toxic substance would require a fundamental change to the HSNO Act and ERMA's role. However, this may be necessary to make exposure limits under the HSNO Act work.

2.3.6 Summary of options

In summary, to improve the workability of tolerable and environmental exposure limits, we propose to:

• set exposure limits as default values but allow regional councils to set less conservative numbers based on site-specific assessment when carrying out a resource consent application assessment (option C)
• set exposure limits, but require people to develop and meet a code of practice that demonstrates that the exposure limits should be met (option D)
• separate the exposure limits-setting process from the approval process (option E).

Options A [Option A: to only set EELs for substances intentionally discharged into the environment.] and B [Option B: to only set environmental and/or tolerable exposure limits if effects are not being managed by the RMA.] can be implemented by ERMA through their internal policy processes. However, we consider that option B will be too difficult in practice to implement. Option C merits investigation as a way to address the conflict between ERMA setting environmental limits at a national level and local background considerations and improves the interface between the HSNO Act and the RMA. However, it does not address the key compliance issues, so is not a solution on its own. Therefore we also propose that options D and E be considered further.