Chemical trespass occurs where agricultural and veterinary chemicals are used or disposed of in a manner that causes:

• Actual or potential contamination of land, animals or plants outside the target area
• Actual or potential harm to human health and safety (within or outside the target area)
• Actual or potential environmental harm (within or outside the target area)

Examples of common chemical trespass incidents include:

• Spray drift or contaminated run-off causing contamination or damage to crops and pastures
• Spray drift causing livestock contamination
• Spray drift, contaminated run-off or unacceptable disposal of unused or waste chemical causing environmental contamination
• Spray drift impacting on human health, eg nausea, headache, respiratory irritation, skin irritation, eye irritation.

Chemical trespass coordinator

Biosecurity SA Rural Chemicals Operations employs a Chemical Trespass Coordinator to manage and coordinate chemical trespass (spray drift) inquiries and complaints on behalf of various government agencies including the Environment Protection Authority, Department of Health and Local Government.

Phone: 08 8226 0528

Email: PIRSA.ChemicalTrespass@sa.gov.au

When reporting chemical trespass incidents, please try to provide as much detail as possible, including:

• Incident date and time
• Incident location
• Name and contact details of chemical user
• How chemical was applied (plane, airblast sprayer, etc)
• Weather conditions
• Chemical involved
• Effect from incident (risk to produce/health/environment)

Refer to the Rural Chemicals Operations fact sheet Guidelines for Reporting Chemical Trespass Incidents (.PDF) for further information.

Fact Sheets, posters and information

PIRSA/BIOSECURITY SA

Rural Chemicals Operations has a range of fact sheets and information about reducing or avoiding chemical trespass.

Working together to minimise spray drift (.PDF)
Encourages communication between chemical users and neighbouring landholders to minimise spray drift problems.

SA Code of Practice for Summer Weed Spraying (.PDF)

Reducing Harm to Honey Bees from Pesticides (.PDF)
This fact sheet outlines practices that beekeepers, pesticide applicators and crop growers can take to reduce the risk of managed bees being harmed by pesticides, particularly insecticides.

Posters

Preventing Chemical Trespass (.PDF) depicts examples of sensitive areas and issues that chemical users should consider when planning spray operations.

Fox Bait Talk Back (.PDF) illustrates some of the risk management practices that must be observed during fox baiting programs. Sodium fluoroacetate (1080), the poison used in fox baits, can also kill dogs and cats.

External sites

Spray Drift Management - Principles, Strategies and Supporting Information (external site)
This CSIRO publication focuses on managing the risks associated with chemical use, in particular the off-target drift. It is essential reading for landowners, spray contractors and operators, growers, government agencies and consultants. It contains useful information about the design and principles of vegetative barriers.

GRDC Spray Drift Fact Sheet (external site)
This fact sheet provides general information about avoiding spray drift, and some technical details about equipment selection.

Nufarm Spraywise - Top tips for drift reduction (external site)

Code of Practice for Summer Weed Spraying

Spraying of summer weeds, to conserve soil moisture and nutrients, is now an integral part of SA cropping systems. GPS and guidance systems allow farmers to spray accurately at night and this practice has been commonly adopted for summer weed spraying. The different atmospheric conditions that prevail at night, particularly the likely presence of surface temperature inversions, mean that farmers have to be very careful with night spraying. In conjunction with the Mid North Spray Drift Committee, Biosecurity SA has developed a Code of Practice for Summer Weed Spraying (.PDF).

All agricultural chemical users must exercise a General Duty of care when spraying and must take all reasonable and practicable measures to prevent chemical trespass. Following the Code of Practice will minimise the off-target risks of summer weed spraying. The Code of Practice is voluntary but chemical users should follow it to to demonstrate their General Duty.

Weather for Spraying

Weather conditions - particularly wind speed, wind direction, temperature and relative humidity - play a key role in reducing the potential for chemical trespass. Recommended weather conditions for spraying are:

• consistent light winds (3-15 km/hr) blowing away from sensitive areas
• mild temperatures and high relative humidity

DO NOT spray under still and inversion conditions, as the distance and direction of spray drift can be unpredictable.

Australian Pesticides and Veterinary Medicines Authority (external site) has information about surface inversions on its website.

Grains Research and Development Corporation (external site) has published "Weather Essentials for Pesticide Application" and a fact sheet about "Surface Temperature Inversions and Spraying" .

A Bureau of Meteorology pamphlet Weather for Pesticide Spraying (.PDF, 593KB) explains the influence of weather on spray application.

Make use of available weather data to plan your spray operations. The Bureau of Meteorology provides weather forecasts and recent weather observations for South Australia. These will give a guide to the prevailing weather conditions for your region. Click on the following links to be taken to the Bureau of Meteorology website.

SA Weather Forecasts (external site)

SA Weather Observations (external site)

In addition to external weather data, you should assess and record weather conditions at the site of application prior to spraying, preferably using a hand-held weather-recording instrument (eg Kestrel® brand (external site)).

Use of 2,4-D, MCPA and Triclopyr near grape growing regions

Reducing drift and off-target damage

A Biosecurity SA fact sheet about 2,4-D (.PDF) provides information about 2,4-D label instructions, as well as an understanding of how these instructions aim to help users manage spray drift. Growers can view a map of grapevines in their area at: www.phylloxera.com.au/statistics/maps (external site)

Reports of suspected herbicide damage to grape vines

Biosecurity SA - Rural Chemicals Program needs to be advised on any suspected cases of off-target herbicide damage to grape vines. Please report any suspected herbicide damage to Rural Chemicals Operations by using the Report of Suspected Herbicide Damage to Grape Vines form (Word file, 95KB).

Buffer zones

There is increasing pressure on spray drift management at the rural-urban interface as residential developments approach land occupied for agricultural or horticultural use. Wherever possible, a buffer zone between contrasting land uses is desirable and can help to alleviate impacts of chemical use, noise, dust, smell, etc.

A PIRSA document "Using Vegetative Barriers to Minimise Off-target Movement of Chemicals" (.PDF, 82KB) describes the issues associated with use of buffer zones.

A Report "Natural and Artificial Barriers for Spray Drift Exposure Mitigation in South Australia" (.PDF, 1.7MB) describes a field study that was conducted in the Mount Lofty Ranges to evaluate the effectiveness of a natural and an artificial barrier for reducing spray drift from a vineyard using two types of vineyard sprayer. There was a difference in drift potential between the two sprayers and the two barriers. The natural vegetation barrier had slightly higher drift reduction than the artificial barrier at near-field distances with a slight increase in deposition at a distance of 20 x barrier height.

The Adelaide Hills Council (AHC) Policy on Buffers (external site), which is publicly available on the AHC website, is a useful guide.

Aquaculture

Fish, including yabbies and marron, are susceptible to many agricultural chemicals - especially insecticides. Before spraying, determine whether there are any aquaculture enterprises nearby that may be at risk if chemical trespass occurs. The PIRSA Aquaculture Public Register indicates the location of marine-based aquaculture lease and licence sites.