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3.2 Ambient standards

Air Quality Technical Report Number 46, Section 2.1, contained the following summary of the proposed ambient air standards:

The key ambient air pollutants of concern are carbon monoxide, particles less than 10 microns in diameter (PM10), nitrogen dioxide, ozone and sulphur dioxide. The proposal sets out a two tiered approach with a level set at the current guideline level with a specified number of times that the standard limit can be exceeded per year and an upper maximum limit that the above exceedances cannot exceed even once.

General issues raised in submissions relating to the standards themselves and how they will be implemented and enforced are summarised below.

Submitters 3, 121, 123 and 206 support the proposed ambient standards and/or their intent. Submitter 123 asks that they be retained as proposed.

Submitters 6, 163 and 174 are concerned that the standards have not been developed according to health-based criteria and that they do not reflect well-debated, expert, national and international best practice and knowledge. The submitters' view is that the standards ignore primary health implications and are inconsistent with the stated objectives. The submitters do not support the concept of an absolute maximum for breaches, or the number of allowable breaches. This is largely because no justification has been provided for the values, they do not appear to have been set on a health basis, and the approaches are inconsistent between pollutants.

Submitters 6, 163 and 174 are concerned that the proposed standards include only one averaging period for each pollutant and that no justification has been provided for the period selected. The submitters seek averaging periods for short and long-term exposures to be included in the standards (where relevant) for health effects, as per the 2002 Guidelines. The submitters are concerned that the standards do not support the key principles of the 2002 Guidelines, which are:

  • not polluting up to guidelines/standards
  • maintaining air quality where it is below guidelines/standards
  • enhancing air quality where it is approaching or exceeding guidelines/standards
  • guidelines/standards are minimum criteria and should not be exceeded.

Submitters 6, 75 and 174 want the status of the 2002 Guidelines to be clarified, particularly regarding contaminants not included in the proposed standard. The submitters also seek clarification regarding contaminants that were identified in the 2002 Guidelines as requiring review. Submitters 6, 163 and 174 seek a commitment to developing a PM2.5 standard within two years.

Submitter 26 is opposed to the ambient standards because they are assumed to apply to the outdoor environment when we spend 85% of our lives indoors.

Submitter 28 seeks guidance for the protection of humans from fluoride, including guidelines for longer periods of exposure such as 300 days per annum. The submitter also seeks a guideline stating the maximum allowable fluoride or other chemical concentrations in soil for vegetable gardens.

Submitter 31 supports the standards because they are based on existing guidelines that have been extensively reviewed. The submitter asks that the concentration limits be adopted as the "bottom line" in terms of ambient air quality and that regional councils may set more stringent limits to maintain and enhance air quality (ie, they are not to pollute up to levels).

Submitter 33 is opposed to the ambient air standards on the basis that if they are interpreted literally they will effectively stifle business growth in Christchurch.

Submitter 37 requests that the Ministry investigate alternative ways to achieve the standards other than command and control, and in particular asks that there be a range of market-based approaches that are effective and efficient. The submitter wants the standards to be rewritten to reflect the importance of implementing and achieving the standards in the most efficient way.

Submitter 75 supports the development of national ambient air quality standards but is opposed to the standards in their current form. The 2002 Guidelines state that "the main goal for sustainable air quality management is to maintain air quality where it is good and to improve air quality where it has been degraded and is affecting people's health". The submitter is concerned about the move away from the Guidelines for PM10 and NO2, with no accompanying reasoning. The submitter is concerned that there is no underlying justification of the number of allowable exceedances, which vary from the Guidelines. The Submitter 75 wants the values in the standards to be based on the 2002 Guidelines because they were developed on the basis of a process of consultation and "well-debated, expert, national and international best practice and knowledge".

Submitter 75 asks that exemptions be provided where the most probable source was non-anthropogenic, or for an event such as Guy Fawkes, and comments that exceedance allowances should be set on the basis of an analysis of the costs and benefits of the impacts of such exceedances. The submitter also wants the sampling frequency to be factored into the standard-setting process, such as the one-day-in-six high-volume method.

Submitter 75 is concerned about the relationship between the maximum limit and concentration limit and which value actually represents the standard, and notes that it is also unclear why all contaminants have not been assigned a maximum limit. The submitter requests that:

  • evidence be provided in support of the proposed standards and number of exceedances, with a comprehensive analysis of all relevant costs and benefits
  • the maximum limits be removed
  • the regulations provide very clear methods of monitoring for compliance
  • a method for defining an air shed be provided
  • no exceedances be allowed for, and that instead a realistic phase-in approach be developed on a regional basis
  • the values and averaging periods for contaminants included in the standards be the same as those for the 2002 Guidelines
  • the standards provide for maintaining and enhancing existing air quality, including areas of good and excellent air quality
  • ambient standards be further developed in consultation with regional councils, including identification of the costs and benefits.

Submitter 85 feels unable to support or oppose the standards because there is a need to clarify the key elements, including:

  • where the ambient standards will apply (ie, the nature of the sites to which ambient standards apply)
  • how and where ambient monitoring sites are to be established to ensure consistency and accuracy
  • how the ambient standards relate to non-point sources, particularly because motor vehicle emissions are not directly regulated by regional councils and regional plans do not form a regulatory means of vehicle emission control
  • how the ambient standards relate to land-use planning and designations.

Submitter 85 asks that transitional actions, targets and responsibilities be specified, and considers the timeframe in which ambient standards are to be achieved needs to reflect the long lead times of measures to improve air quality. The submitter wants the standards to state that vehicle emissions are non-point sources, and believes that further policy development and clarification need to occur if the standards are to apply to non-point emissions.

Submitters 88, 91, 117, 153, 167, 170, 172, 180, 215 and 219 are opposed to the standards and consider that the standards should not proceed until:

  • the 2002 Guidelines are not working and compulsory standards are needed
  • the costs and benefits to a range of industries in each region have been assessed at a local level
  • there is a reasonable period of consultation.

Submitter 90 supports the introduction of the specified number of exceedances and an upper maximum limit, and considers that the specified exceedances resolve ambiguity in the 2002 Guidelines as to the meaning of the 99th percentile.

Submitter 93 wants the ambient standards to be amended to remove discretion for local government to apply the standard in response to local conditions because a standard capable of re-interpretation will do little to meet the objectives of consistency, certainty and a level playing field.

Submitter 98 seeks an extension to the timeframe within which the ambient standards come into force because of the costs involved in meeting the standards in a short timeframe.

Submitter 109 supports the ambient standards and notes that they do not preclude a region from taking a more restrictive approach where the local conditions warrant it.

Submitter 117 wants the application of the standards to be deferred until the actions outlined above have been taken.

Submitter 119 wants the principles behind the justification and incorporation of compliance criteria in the ambient standards to be made clear (ie, the averaging periods selected and the inclusion of maximums). The submitter seeks clarification as to why no annual averaging period has been used in the ambient standards, and, if necessary, that this be provided.

Submitter 127 is opposed to the establishment of ambient air quality standards and considers that there has been insufficient analysis of the legal implications and their workability in practice. The most appropriate mechanism for achieving better air quality is a combination of national standards, as proposed for some emissions, and the development of robust methodologies for specifying requirements for discharges to air in regional plans.

Submitter 130 considers that there should be a specific exclusion for emergency and network load-shedding generators, because it would be nonsensical for national standards to prevent the use of emergency generators during a power crisis and network load shedding can avoid costly upgrades of main transmission lines. Alternatively, specific standards could be set to provide a permitted activity for modern, high-efficiency diesel generators.

Submitter 133 requests that the following omissions be addressed: benzene, 1,3-butadiene, benzo(a)pyrene, formaldehyde, metals (lead, mercury, chromium and arsenic) and PM2.5.

Submitter 136 considers that there should be a phased approach to the standards to allow for the permitted number of exceedances to reduce over time as technologies improve. The submitter asks that forecasted traffic growth be factored into projected emissions when considering the potential for exceedances in an air shed.

Submitter 145 considers that the use of the term "maximum limit" to be confusing and queries which criteria is the standard: the maximum limit or the standard limit? Submitter 145 wants the maximum limits to be removed.

Submitter 153 opposes the standards because they would have major impacts on discharges that have particulate matter emissions and would have negative consequences in areas that exceed the standards. The submitter asks that standards only be imposed where it can be shown that local planning is not working, and requests that any standard be grounded in a robust cost-benefit analysis and any changes to the proposal include adequate consultation consistent with the RMA.

Submitter 155 considers that all the proposed standards should be demonstrated to have integrity by the competent application of scientific and engineering knowledge in respect of the assessment of environmental effects, and full peer review. This is not the case for the majority of the information presented in the proposed standards.

Submitter 162 comments that there is a lack of clarity about where the standards will apply and seeks a definition as to where the standards apply, or a mechanism whereby regional councils can determine this.

Submitters 161 and 201 support the proposed standards being applied to the air outside houses and buildings and beyond the property boundary. The statement "where people may be affected" should be clarified to ensure that the boundary is not the de facto measurement point. Wording such as "where people live or gather outside the boundary" is preferred, and the use of "affected" should be changed to "exposed for the periods relevant for each pollutant".

Submitters 125 and 224 request that where the standards apply should be clarified to specifically address ambient air quality, and that the standards distinguish between ambient monitoring sites and "hot spot" sites.

Submitter 175 is concerned that the wording "the standard only need apply where discharges affect where people live or gather outside that site from where the discharge originates" is very vague.

Submitter 183 requests that:

  • all significant sources be accounted for, including vehicles
  • a clearer indication of the policy underpinning the standards be provided
  • consideration be given to extending the four-year timeframe for implementation
  • incentives for non-profit organisations to reduce emissions be considered
  • certainty be provided as to whether the standards are primarily for the industrial sector or for broader application
  • controls over school boilers or other combustion processes as a result of the standards be not unduly restrictive
  • the standards be technically and environmentally sound, as well as economically and socially viable
  • the role of tangata whenua and the Treaty of Waitangi be articulated.