Managing Operational Discharges

This section describes the aerial application, risk factors and management options (pilot management options and plan provision options) for the three types of aerial applications. A summary table of management options is provided for each aerial application type (fertilisers, agrichemicals and VTAs), which identifies:

  • Potential adverse effects.
  • Risk factors.
  • Exposure pathway.
  • Pilot management options.
  • Options for plan provisions and consent conditions (note this is not provided for VTAs).

When identifying the appropriate management option, it is also important to assess the key considerations and section 32 requirements when developing plan provisions and controls to manage the adverse effects of the agricultural aviation industry.

Fertilisers

Fertilisers are substances that are applied to land to improve the productivity of plants for primary production, which includes pastoral farming (sheep, beef, deer and dairy), horticulture, viticulture, and forestry. They are critical to the success of primary production and therefore contribute to GDP and the economic well-being of communities. Fertilisers are also used on sports fields and golf courses. About 600,000 tonnes of fertiliser is applied by air annually in New Zealand, both by fixed wing aircraft and helicopters.

There is a wide range of fertilisers used for different purposes, in both solid and liquid forms. The most common types are superphosphate and nitrogen based fertilisers. Essential nutrients to retain soil balance, such as potassium and sulphur, magnesium and cobalt, are also applied as fertilisers or added to fertiliser mixes.

Fertiliser definitions

The ACVM (Exemptions and Prohibited Substances) (ACVM (E&PS)) Regulations 2011 defines a fertiliser and requirements and conditions for fertilisers. Relevant definitions in these regulations are as follows:

Fertiliser

  1. means a substance or biological compound or mix of substances or biological compounds that is described as, or held out to be for, or suitable for, sustaining or increasing the growth, productivity, or quality of plants or, indirectly, animals through the application to plants or soil of—
    1. nitrogen, phosphorus, potassium, sulphur, magnesium, calcium, chlorine, and sodium as major nutrients; or
    2. manganese, iron, zinc, copper, boron, cobalt, molybdenum, iodine, and selenium as minor nutrients; o
    3. fertiliser additives; and
  2. includes non-nutrient attributes of the materials used in fertiliser; but
  3. does not include substances that are plant growth regulators that modify the physiological functions of plants.

Fertiliser additive

  1. a non-nutrient substance added to a fertiliser, or applied to land by itself, that—
    1. improves the supply and uptake of nutrients; or
    2. increases the biological activity of soil; or
    3. modifies the physical characteristics of a fertiliser to make it more fit for its purpose;

      but
       
  2. does not include substances that are plant growth regulators that modify the physiological functions of plants.

These definitions are considered appropriate for incorporation into plan provisions. Agricultural lime is applied to condition and change the pH of the soil and under these definitions is considered to be a fertiliser additive.

For other definitions of fertiliser see the Technical Information relating to the Agricultural Aviation Industry.

Relevant legislation relating to fertilisers

Fertilisers are managed under both the HSNO and ACVM Acts. While not specifically mentioned or provided for in the RMA, fertilisers can also be managed under the RMA as they fall within the definition of contaminants.

Regional councils are responsible for managing fertiliser discharges to air, onto or into land and/or water. The application of fertiliser, including aerial applications, is generally provided for in regional plans as a permitted activity, subject to conditions.

Territorial authorities are primarily responsible for the management of land use activities which can include the control of hazardous substances. As most fertilisers are classified as hazardous substances they are managed under the HSNO Act. However if councils consider that HSNO controls are not sufficient to meet the purpose of the RMA, then councils can address this through their district plans. District plans should address the storage of fertilisers. HSNO Act regulations are also relevant in this regard and are discussed further in Technical Information relating to the Agricultural Aviation Industry. Under the ACVM Act, the requirements for end users are outlined in the ACVM (E&PS) Regulations.

Aerial Application of fertiliser

Superphosphate is typically applied from the air at rates of between 100 and 300kg/ha over complex topography where no other application methods are viable. Superphosphate fertilisers tend to be of variable quality in terms of particle size and size range. Nitrogen based fertilisers (and other high analysis fertilisers) tend to be applied over more productive, and hence more uniform land for both pasture and cropping. Nitrogen based fertilisers are also usually more uniform and consistent in terms of particle size.

Maximising the productivity gains from fertiliser application requires evenness of application across the target area. Achieving an even application within the target area has an impact on the precision of application (i.e. the requirement to confine the fertiliser to the target area). There are a range of systems, equipment and techniques required to consistently and reliably achieve an even application of fertiliser and this also enables fertiliser applications to be confined to the target area.

There are a number of publications setting out best practice for fertiliser application including:

For more information on these codes and standards see Technical Information relating to the Agricultural Aviation Industry.

Risk factors of aerial application of fertilisers

The key risk factors for aerial application of fertiliser are particle size, wind speed and wind direction. It is important to recognise that not all fertiliser has the same physical characteristics. The particle size of fertilisers varies, which directly affects the ballistic property of the substance and how it falls when discharged. Coarser particle size means that the product trajectory will be more predictable, whereas a smaller particle size presents a greater likelihood of off-target drift and dust.

Wind speed at the time of application influences how far the fertiliser will travel from the point of release. At a given wind speed, small particles will move down wind further than large particles. Wind direction determines the direction in which the fertiliser particles will travel. Both wind speed and wind direction needs to be factored in by the pilot, along with the product quality and particle size to determine flight paths, to avoid sensitive areas, and to ensure the product is applied to the target area. An operator can verify the track flown and where they have discharged fertiliser. However to accurately verify where the product has landed requires information on wind speed (which influences how far the product will go from the track flown) and wind direction which determines the direction the fertiliser particles will travel from the point of release.

Management options for the aerial application of fertilisers

The risk management section sets out the general framework for a risk management approach for aerial applications. This section provides guidance on how to apply this approach specifically to manage the discharge of fertilisers. Table 5identifies management options for plan provisions and consent conditions to manage the adverse effects from the aerial application of fertilisers based on the type of adverse effect, relevant risk factors and the exposure pathway. It also identifies the measures pilots can take to minimise risks and potential adverse effects from the aerial application of fertilisers.

Table 5: Risk management approach for aerial application of fertiliser

Potential adverse effects Risk factor Exposure pathway Pilot Management Options (see Technical Information relating to the Agricultural Aviation Industry Information relating to the Agricultural Aviation Industry and the Aerial Spreadmark Code Spreadmark Code) Options for plan provisions and consent conditions

Health effects which may include:

  • Allergic reactions
  • Irritations
  • Toxic poisoning
  • Hazard class of chemical (substance) being used and exposure to it (HSNO Classes[1] 6, 8 and 9)

Indirect:

  • Off-target drift or dust

Direct:

  • Applications to non-target area through handling and loading

Indirect:

  • Minimise potential for drift – technical options

Direct:

  • Personal Protective Equipment - management of loading and handling operations
  • Require documentation of operator risk assessment to ensure use of appropriate technical options can be verified if required
  • Classify dwellings, educational facilities and public places as sensitive areas (drift hazard of fines)
 

Contamination of crops and plants including sensitive crops and organically farmed properties;

  • Growth and quality of the crop; or
  • Threatens organic registration

Fertiliser type:

  • Excessive residue levels
  • Timing of application
  • Crop stage
  • Application rate – calibration
  • Drift

Indirect:

  • Off-target drift

Indirect:

  • Minimise potential for drift – technical options
  • Require documentation of operator risk assessment to ensure use of appropriate technical options can be verified if required
  • Classify crops and non-target plants as sensitive areas

Contamination of domestic or commercial water supplies where it renders the drinking water non-potable

Fertiliser hazard and type:

  • HSNO Classes 6 and 8

Indirect:

  • Off-target drift

Direct:

  • Applications to non-target area

Indirect:

  • Minimise potential for drift – technical options
  • Require documentation of operator risk assessment to ensure use of appropriate technical options can be verified if required
  • Classify water bodies/ drinking water supplies as sensitive areas
  • It may be appropriate to include conditions or other restrictions for some applications over or near water bodies
 

Contamination of indigenous flora, fauna, habitat areas and reserves where the inherent values of these areas are damaged or lost

Ecotoxicity of fertiliser:

  • HSNO Classes 9.2, 9.3A and 9.4A
  • Poor/no target identification
  • Fertiliser quality (particle size and stability)

Indirect:

  • Off-target drift

Direct:

  • Applications to non-target area

Indirect:

  • Minimise potential for drift – technical options*
  • Target site identification (GPS)
  • Ensure that fertiliser quality is appropriate to minimise potential for drift
  • Require site identification as part of risk assessment
  • Classify as sensitive areas
 

Contamination of wetlands, surface water bodies, and coastal and marine environments where it causes:

  • Death of flora and fauna
  • Water takes affected leading to un-potable water or damage to crops and animals

Fertiliser type and hazard:

  • HSNO Classes 6, 8 and 9
  • Application rates
  • Location of application and proximity to water take points
  • Inappropriate disposal
  • Poor/no target identification
  • No identification of at-risk water bodies
  • Non-point fertiliser – dust

Indirect:

  • Applications adjacent to water bodies – off-target drift or overland flow
  • Disposal adjacent to water

Direct:

  • Applications into water
  • Spillages/ overflows at mixing sites
  • Disposal to water
  • Management measures for loading sites
  • Follow label requirements
  • All reasonable measures must be taken to avoid discharges to surface water bodies – risk assessment to establish appropriate measures
  • Use of fertiliser with good ballistic properties (particle size)
  • Require that loading sites in proximity to water bodies be managed to contain spillages
  • Require documentation of operator risk assessment to ensure use of appropriate technical options can be verified if required, including identification of sensitive areas
  • Require that all reasonable measures are taken to avoid discharges to surface water bodies
  • Classify water bodies as sensitive areas
  • Require label requirements to be followed
 

Contamination of groundwater

  • Concentration of fertiliser and application rates
  • Soil type – highly permeable and fertilisers that are mobile

Indirect:

  • Leaching through soil

Direct:

  • Spillages/ overflows at loading sites
  • Inappropriate disposal

Direct and indirect:

  • Inappropriate disposal of wastes
  • Management of loading sites
  • Ensure that client has established appropriate rate, concentration gradient for the soil profile
  • Methods of disposal
  • Require that loading sites in proximity to wellheads be managed to ensure that spillages are contained
 

 

Contamination of soils/ land which may cause death of flora and fauna

  • Fertilisers that are, or contain substances not mobile in soil
  • Inappropriate application rates
  • Inadequate containment at loading sites

Indirect:

  • Permeability – water moves nutrients through soil profile but contaminants e.g.: Cd and F remain bound to soil particles

Direct:

  • Frequency and rate of application of fertiliser
  • Follow use requirements
  • Ensure that client has established appropriate rate, for the soil profile
  • Loading sites, and storage
  • Label requirements to be followed
  • Ensure management of loading sites to contain spillages
   

Amenity values

  • Proximity of people – timing and location
  • Fertiliser volatility and toxicity class
  • Aircraft operating

Indirect:

  • Off-target drift

Direct:

  • Exposure if public in public areas at time of application

Noise:

  • Aircraft and machinery
  • Minimise potential for drift – technical options
 
  • Classify high amenity areas as sensitive areas
  • Plan provisions relating to reverse sensitivity in rural areas (including noise and drift) to identify what is reasonably expected in the rural area

All potential adverse effects

   
  • Competent to carry out risk assessment for operation
 

 

Agrichemicals

The term ‘agrichemical’ is commonly used to describe a range of substances that control pests. Agrichemicals are applied to land, water or crops to control pests in primary production activities of pastoral farming (sheep, beef, dairy and deer), horticulture, viticulture and forestry.

Examples of agrichemicals include:

  • Herbicides to control unwanted plants, including some that are specific for aquatic use in water;
  • Insecticides to control insects such as clover flea or potato psyllid;
  • Fungicides to control fungus e.g. rust, mildew, moulds; and
  • Plant growth regulators e.g. Hi Cane.

Agrichemicals are usually discharged into air rather than applied directly onto the target species. Under the RMA such applications are classed as a discharge of contaminants to air, land or water.

Agrichemical applications can be by both fixed wing aircraft and helicopters, and vary due to a range of factors so plan provisions need to be appropriate, flexible and applicable across the range of situations. Aerial application of agrichemicals range from total vegetation control (e.g. pre-plant herbicide application in cropping and forestry) where confining the spray to the target area is the first priority, through to application of a biological insecticide as a biosecurity requirement (e.g. Painted Apple Moth eradication in Auckland). In the latter case, large urban areas were sprayed with small spray droplets in specific local wind conditions to achieve the required target penetration and coverage.

Definition of Agrichemical

The terms agricultural chemicals, agricultural compounds and pesticides are often used to describe the same or similar groups of products. The terminology and definition used in a plan is important so it is clear exactly what substances fall within the parameters of any regulation.

The most commonly used definition in RMA plans is the definition from NZS 8409:2004 Management of Agrichemicals (NZS 8409) which defines agrichemicals as:

“Any substance, whether inorganic or organic, man-made or naturally occurring, modified or in its original state, that is used in any agriculture, horticulture or related activity, to eradicate, modify or control flora and fauna. For the purposes of this Standard, it includes agricultural compounds but excludes fertilisers, vertebrate pest control products and oral nutritional compounds.”

This definition is considered appropriate to incorporate into plan provisions.

Pesticides are not defined in regulations or the HSNO or ACVM Acts. Pesticides can include a wider range of substances than the definition of agrichemical in NZS8409. Pesticides generally include any chemical mixture of substances intended for preventing, destroying or controlling any pest. For example, VTAs or timber treatment chemicals would be classed as a pesticide, but not as an agrichemical as defined in NZS 8409. For other definitions see the Technical Information relating to the Agricultural Aviation Industry.

Aerial Application of Agrichemicals

Aerial application of agrichemicals normally involves mixing it with water in a spray tank according to the rate and concentration specified on the product label[2]. It is then applied using a boom fitted to the aircraft that has the appropriate number and type of nozzles fitted. The nozzles regulate the flow rate and determine the droplet size produced. Getting an even spray pattern from an aircraft, whether fixed wing or helicopter, depends on the way in which the spray boom and nozzles are mounted on the aircraft.

Most aerial spraying of agrichemicals in New Zealand involves herbicide application where it is important to ensure maximum deposition onto the target, while minimising off-target drift. The application equipment used, the way this equipment is fitted and the type of aircraft can significantly affect the extent to which off-target drift is minimised.

Sometimes a different technique is needed, where lateral movement of small droplets in the spray is used to obtain large swath widths and horizontal droplet deposition. Examples of this technique in New Zealand include fungicide application to broad-acre crops and control of pest incursions such as the Tussock Moth and Painted Apple Moth. This technique can produce very good target coverage but containing such spray in the target area is more difficult.

There are existing industry best practice standards for agrichemical application. The most relevant is NZS 8409.This performance standard applies to any agrichemical application, including aerial methods. NZS 8409 was developed by Standards New Zealand and sets out the requirements for the safe, responsible and effective management of agrichemicals. EPA has approved NZS 8409 as a Code of Practice under the HSNO Act and by complying with the standard you are considered to have met ACVM conditions. NZS8409 is one of the Codes of Practice that form part of the AIRCARE™ Accreditation programme.

Risk factors of aerial application of agrichemicals

There are a number of potential adverse effects that can arise from agrichemical applications and the nature of these effects will vary depending on the combination and level of risk factors for the operation. The relevant risk factors for the discharge of agrichemicals include:

  • The chemical being used, hazard class and type, and exposure to it.
  • The concentration and rate of application of the chemical.
  • The timing of the application.
  • Location of sensitive activities.
  • The proximity of people – timing and location.
  • The location of the application and use, including mixing sites.
  • Weather conditions.
  • Spray quality.
  • Target identification.
  • The permeability of the soil.
  • Whether non-target animals are present (e.g. when applying to pasture).

In seeking to avoid or minimise adverse effects from the discharge of agrichemicals, these risk factors must be assessed and addressed in the context of the relevant exposure pathways.

Exposure pathways and management options

The exposure pathways for agrichemicals can be either:

  • Indirect – off target drift, leaching, overland flow; or
  • Direct – application on subject areas, point source discharges (e.g. spillages).

Off target drift - Spray drift and drift hazard
Drift hazard is defined in NZS 8409 as the hazard associated with drift and consequent trespass which may result in an adverse effect to human health, animal health or the environment.

Every spray application of agrichemicals will result in some degree of spray drift as it is not possible to have zero drift due to the range of variables. However, the most important issue from a risk managementperspective is what risk the spray drift poses and how the risk can be avoided or minimised.

Appendix G of NZS 8409 provides a drift hazard guidance chart. Technical Information relating to the Agricultural Aviation Industry includes a potential draft hazard scale from NZS 8409. This table highlights the range of variables that need to be considered such as wind speed and direction, height and application, and sensitive areas. It also identifies ways to address these hazards which requires knowledge of all the variables that are relevant to the agrichemical application at the time. Table 4.1 in the Technical Information distinguishes between pre-determined and real-time factors and identifies that the most significant factor causing adverse effects from off target spray drift is almost always wind direction – a real-time factor.

Plan provisions relating to the discharge of agrichemicals need to ensure they recognise these options so that they are assessed at the time of application.

Management options for the discharge of agrichemicals

The risk management section sets out the general framework for a risk management approach for aerial applications. This section provides guidance on how to apply this approach specifically to manage the discharge of agrichemicals.

For each potential adverse effect, table 6 identifies the relevant risk factor, exposure pathway and management options to manage potential adverse effects for both the pilot and councils. The extent to which a risk factor applies and management options need to be considered varies according to the nature of the receiving environment and the potential adverse effect.

Table 6: Risk management approach for aerial application of agrichemicals
         

Potential adverse effects Risk factors Exposure pathway

Pilot management options

(see Technical Information relating to the Agricultural Aviation Industry Agricultural Aviation Industry)

Options for plan provisions and consent conditions

Health effects caused or possible:

  • Allergic reactions
  • Irritations
  • Toxic poisoning
  • Exposure to carcinogens and teratogens
  • Hazard class of chemical being used and exposure (HSNO Classes 6 and 8)
 

Indirect:

  • Off target drift

Direct:

  • Applicator

Indirect:

  • Minimise potential for drift – technical options
  • Notification (drift hazard)

Direct:

  • Personal Protection Equipment
  • Require documentation of operator risk assessment to ensure use of appropriate technical options can be verified if required
  • Classify dwellings, educational facilities and public places as sensitive areas
  • Require notification where application adjacent to sensitive areas

Potential toxicity to bees and other pollinators, including beneficial insects (insects that perform valued services like pollination and pest control)

  • Chemical type (herbicide, insecticide, fungicide etc.)
  • Excessive residue levels

Indirect:

  • Off target drift
  • Minimise potential for drift – technical options
 
  • Require documentation of operator risk assessment to ensure use of appropriate technical options can be verified if required, including identification of sensitive crops and methods to avoid drift onto those areas

Contamination of crops and plants including sensitive crops and organically farmed properties.

Effects include:

  • Chemical type (herbicide, insecticide, fungicide etc.)
  • Excessive residue levels
  • Timing of application – crop stage
  • Application rate (calibration)

Indirect:

  • Off target drift
  • Minimise potential for drift – technical options
 
  • Require documentation of operator risk assessment to ensure use of appropriate technical options can be verified if required, including identification of sensitive crops and methods to avoid drift onto those areas
  • Classify crops and non-target plants as sensitive areas
  • Require notification to greenhouse operations in the area

Contamination of domestic or commercial water supplies where it renders the drinking water non-potable

Chemical type and hazard class:

  • HSNO Classes 6 and 8

Indirect:

  • Off target

Direct:

  • Discharges
  • Minimise potential for drift – technical options
  • Require documentation of operator risk assessment to ensure use of appropriate technical options can be verified if required
 
  • Classify water supplies as sensitive areas
  • It may be appropriate to include conditions to avoid direct applications over such areas

Contamination of indigenous flora and fauna, habitat areas and reserves where the inherent values of the areas are damaged or lost

(Note: in considering effects consideration should be given to whether the application is specifically for the control of environmental weeds in areas of native vegetation / reserve land)

  • Ecotoxicity of substance (HSNO Classes 9.2, 9.3A and 9.4A[3]
  • Poor or no target identification
  • Spray quality

Indirect:

  • Off target drift

Direct:

  • Applications
  • Minimise potential for drift – technical options
  • Target site identification (GPS)
  • Require site identification as part of risk assessment
  • Require documentation of operator risk assessment to ensure use of appropriate technical options can be verified if required
  • Classify as sensitive areas (except in relation to environmental weeds in areas of native vegetation / reserve land)

Contamination of wetlands, surface water body and coastal and marine environments where it causes:

  • Death of flora and fauna
  • Water takes affected leading to un-potable water or damage to crops and animals

(Note: in considering effects consideration should be given to whether the application is specifically for the control of environmental weeds in wetlands and other waterbodies).

  • Chemical type and Hazard Classes 6, 8 or 9
  • Concentration of chemical and application rates
  • Location of application in proximity to water take points
  • Inappropriate disposal
  • Poor or no target identification
  • No identification of at-risk water bodies
  • Non-point spray quality

Indirect:

  • Applications adjacent to water bodies – off target drift or overland flow
  • Disposal adjacent to water

Direct:

  • Applications into water is prohibited for the vast majority of pesticides, but could still occur
  • Spillages/ overflows at mixing sites
  • Disposal into water is prohibited for the vast majority of pesticides unless it has been treated first and made non-hazardous
  • Minimise potential for drift – technical options
  • Target site identification (GPS)
  • Management measures of mixing sites NZS8409 Section 5.3.2 and Appendix R
  • Management of disposal NZS8409 Section 6 and Appendix 6
  • Require reasonable measures be taken to avoid discharges to surface water bodies unless for intended aquatic use[4].
  • Operator risk assessment undertaken and documented to establish reasonable measures and ensure use of appropriate technical options
  • Classify water bodies as sensitive areas (except in relation to aquatic herbicides)
  • It may be appropriate to include conditions to avoid direct applications over such areas (except in relation to aquatic herbicides and other environmental weeds such aswillow, spartina, tradescantia, alligator weed)

Contamination of groundwater

  • Concentration of chemicals and application rates
  • Soil type – highly permeable and chemicals that are mobile

Direct:

  • Spillages/ overflows at mixing sites

Indirect:

  • Leaching through soil 

Direct and indirect:

  • Inappropriate disposal of unwanted agrichemicals and surplus spray mix
  • Management measures of mixing sites – bunded etc. NZS8409 Section 5.3.2 Appendix R
  • Appropriate rate, concentration, gradient, soil profile (e.g. GROWSAFE calculator)
  • Methods of disposal NZS8409 Section 6 and Appendix S
  • Require compliance with NZS8409 Section 6 and Appendix S and Section 5.3.2 and Appendix R (must specify the exact date and version of the standard as standards can be subject to change)
 

Contamination of soils/ land

  • Use of substances that persist and accumulate in the soil – e.g. copper
  • Inappropriate application rates
  • Inadequate containment at storage and mixing sites

Direct:

  • Frequency and rate of application of persistent chemicals

Indirect:

  • Permeability – includes water source to move through the soil profile
  • Appropriate tools (e.g. GROWSAFE calculator)
  • Fate processes NZS8409 Appendix F
  • Mixing sites and storage NZS8409 Section 4 Appendix L
  • See label requirements
 
  • Require that NZS8409 Section 4 and Appendix L are met (must specify the exact date and version of the standard as standards can be subject to change)

Amenity values

Offensive and/or objectionable effects such as:

  • Limiting access to public areas
  • Off target drift other than health and vegetation damage
  • Excessive noise
  • Proximity of people – timing and location
  • Chemical – volatility and toxicity class
  • Air craft and machinery operating
 

Direct:

  • Exposure if in public areas at time of application
  • Off target drift
  • Noise – aircraft and machinery
  • Minimise potential for drift – technical options
  • Notification (drift hazard)
 
  • Classify amenity areas as sensitive areas
  • Plan provisions relating to reverse sensitivity in rural areas (including noise, odour, spray drift) to identify what is to be reasonably expected in the rural area

All potential adverse effects

   
  • Competent to carry out risk assessment for operation
  • Recommend pilot competency through Pilots Agrichemical Rating issued by CAA and that the operator is accredited for agrichemicals
 

 

Vertebrate Toxic Agents

This section provides background information on the safe and responsible management of the most common aerial application of VTAs – 1080 applied as cereal bait or carrot bait[5]. VTA (as defined in the ACVM Standard for Vertebrate Toxic Agents) is “a toxic substance used to kill or reduce the viability of vertebrate animals. It does not include attractant or repellent substances that are not toxic”. VTAs, commonly referred to as baits, are substances, inorganic, human made or naturally occurring, modified or in its original state, that are used to kill, control or limit the viability of vertebrate pests, including possums, rats, rabbits, mice and mustelids. These substances are sometimes known as vertebrate pest control products and include products that have a negative effect on reproduction.

This section does not provide options for managing VTAs in district and regional plans. The Parliamentary Commissioner for the Environment (PCE) found that where controls and consent conditions are imposed under the RMA they often create unnecessary inconsistency or duplication with controls under the HSNO Act. Therefore, councils are encouraged to pursue this matter under the HSNO Act and to refer to relevant resources such as:

Aerial application of VTAs

Aerial application of 1080 usually involves the 1080 substance contained within cereal bait or it is added as a soluble concentrate on site with carrot bait. Bait containing 1080 is principally used to manage possums in the Conservation estate to protect indigenous flora and fauna and on primary production land to control possums as vector carriers of TB to cattle. Rabbits are also controlled by using 1080 and Pindone.

Guidelines and standards for aerial 1080 are available on the EPA’s website. In addition, the main users of 1080, such as the Department of Conservation (DOC) and TBfree New Zealand have developed their own Standard Operating Procedures (SOP’s), and other bodies have developed best practice measures for the aerial application of VTAs, including:

Note that management of VTAs is not included within NZS8409: 2004 Management of Agrichemicals, therefore the standard is not an appropriate management tool for VTAs.

Risk Factor of aerial application of VTA

ERMA’s Decision (now EPA) for the reassessment of 1080 (Table C1) has already assessed the level of risk for the application of VTAs and has accordingly set national controls to manage the potential risks. Hazard classifications for sodium fluoroacetate (1080) and formulated substances containing 1080 are given in Section 7 of the reassessment.

Overview of management options for the aerial application of VTAs

The application of 1080 is regulated under the HSNO Act by the EPA, with the EPA risk assessment controlling its use. There are also controls on their use under the ACVM Act, which is administered by MPI.

The former Environmental Risk Management Authority (ERMA), now the EPA, undertook a reassessment of 1080 in 2007. This assessment provides full information on the product, risks and controls which must be met by operators. It looked at the broader environmental effects of 1080, and identified that existing hazardous substance controls are adequate to control the adverse effects of 1080 on public health and the environment. This assessment recommended that more effort should be put into ensuring that the existing controls are complied with by all users of 1080 through implementation of best practice guidelines and standards. For more information, see the 1080 webpage on the EPA website.

While the application of VTAs is considered a discharge of contaminants to air, land or water under the RMA,additional controls under the RMA (through consent conditions or district or regional plan provisions) should only be used to address a resource management issue which a council considers is not adequately controlled by the EPA under the HSNO Act.

The following table sets out a risk management approach for use of VTAs. It is based on the ERMA (now EPA) reassessment of 1080 in 2007 and provides examples of how pilot management options give effect to controls under the HSNO Act.

Table 7: Risk management approach for VTA (1080) use

Potential adverse effects

Risk factor*

Exposure pathway (Nature of risk)

Examples of pilot management options addressed under the HSNO Act

(see Technical Information relating to the Agricultural Aviation Industry)

Adverse human health effects (both short and long term)

(Note: risks to public health from 1080 are covered by the HSNO Act public health permission)

B

Minor/ Improbable

Exposure of occupationally exposed persons during the handling of treated carrot and apple baits in the field and from handling cereal pellets if Personal Protection Equipment is not worn correctly.

Nature of risk:

  1. The risk is voluntary;
  2. The risk will not persist over time (exposure is not on-going and the effect will not persist across generations since 1080 is not mutagenic);
  3. The risk is controlled in scope and location;
  4. The potential effects may be irreversible but information was incomplete on this aspect;
  5. There is good understanding in the occupational setting for managing exposure (e.g. protective equipment) and little risk of public exposure.
  • Ensure all personnel involved have and use appropriate Personal Protection Equipment.

Effects following direct exposure to pellets during aerial operations and coated baits on:

  1. native birds
  2. native mammals (bats)
  3. native herpetofauna (frogs and lizards)

A – D

D

A - C

Nature of risk:

  1. Exposure of organisms to the substance is involuntary
  2. The risk will not persist over time as 1080 is biodegradable
  3. The effects are controllable and would be irreversible only in the event of the loss of a species or a significant population
  4. Risks are generally well understood by users of formulated substances containing 1080 and can be managed, but are less well understood by the general public
  • Ensure accurate GIS mapping of target area
  • Clearly identify target area boundaries and water bodies
  • Avoid flight outside target area while undertaking the operation
  • Don’t apply bait outside the target area

Effects following indirect exposure on non-target food producing animals.

**

Nature of risk:

  1. Exposure of animals to the substance is involuntary
  2. Potential for residue to occur in food or milk
  3. The risk will not persist over time as 1080 is biodegradable
  4. The effects are controllable and would be irreversible only in the event of the loss of a species or a significant population
  5. Risks are generally well understood by users of formulated substances containing 1080 and can be managed, but are less well understood by the general public
  • Ensure accurate GIS mapping of target area
  • Clearly identify target area boundaries and water bodies
  • Avoid flight outside target area while undertaking the operation
  • Don’t apply bait outside the target area

* See ERMA Decision - Table 12.2 (Overall evaluation of adverse effects). The ‘level of risk’ column in the guidance note reflects the information in the last column of Table 12.2 (‘level of risk adjusted to take account of approach to risk’). For further information, refer to Appendix C ‘Qualitative descriptors for risk/benefit assessment’ for additional information, particularly Section C2 ‘Describing the magnitude of the effect’ (pg. 203) and Table C5 (Assignment of level of risk/benefit, pg. 206).

** Not included in ERMA Decision

 


[1] These refer to the HSNO Classification Codes. A full list is available on the EPA website.

[2] Note that Appendix C3.2 of NZS 8409 specifies use outside of conditions (off-label use)

[3] Note that just because a product does not have a high 9 classification under the HSNO Act it does not mean that it does not pose a risk to the environment. This is because the HSNO Act only considers acute effects for classification which could be problematic when considering other impacts such as reproductive effects.

[4] Aquatic herbicides are used to control weeds in some wetlands. This activity is typically undertaken by DOC, MPI, regional councils, territorial authorities, farmers and contractors. The use of aquatic herbicides onto or into water is not a matter for regional and district plans, as it is controlled by the EPA pursuant to section 95A of the HSNO Act.

[5] This guidance note does not address applications of other VTAs, such as pindone pellets, or non-aerial methods of applying VTAs.