Executive summary
This report investigates potential air quality issues from viticulture spraying, including the potential accumulation of chemicals in the Blenheim area. The report stems from concerns about the adequacy of existing legislation and practices in protecting the environment given the significant increase in the amount of land being used for vineyards in the Blenheim area.
The main objective of the report was to identify the chemicals with the greatest potential for accumulation in the air over Blenheim and those that posed that greatest risk in terms of toxicity. The information could then be used to develop a monitoring strategy to determine the potential impacts of any accumulation of spray in Blenheim and potentially result in the implementation of additional measures to avoid, remedy or mitigate the effects of viticulture sprays.
Accurate quantification and assessment of potential impacts was not possible because of issues relating to data collection and collation. However, the analysis suggests that around 115 tonnes of sulphur could be released in the vineyards around Blenheim per year. A range of chemicals are released in smaller quantities that have greater toxicity. Identification of a specific chemical for monitoring was not possible because of uncertainties in the amounts of different chemicals used.
Internationally there is little information available on an effective strategy or design of a programme for monitoring air accumulation impacts associated with spray drift. The topic is currently being researched in America and it is likely that recommendations for monitoring will be available within the next few years. A monitoring strategy could be developed in the absence of the American research results. However, it may be more cost effective to wait for the latter, and for better information on the quantities of chemicals used, before progressing with an extensive programme. A preliminary investigation, however, could measure sulphur as an indicator of the potential for accumulation.
Notwithstanding the current information gaps, this study identifies a number of issues in the industry and makes recommendations including revisions to the proposed Wairau/Awatere plan to better regulate the spray industry. Information requirements regarding these issues are outlined in the report. Marlborough District Council and industry could take several steps to improve base line data. These include:
- Developing working relationships with key industry organisations including New Zealand Winegrowers.
- Reviewing agrichemical requirements in the proposed Wairau/Awatere Plan to improve clarity and consistency for applicators, provide for collation of agrichemical use data, sensitive area identification, notification, signage etc.
- Investigate all drift complaints using a standardised format to improve monitoring and record vital information.
- Increase awareness throughout the community of complaints processes and inform complainants of any outcomes. Annual communication with other data collection agencies, for example the National Poisons Centre to ensure that the number of agrichemical incidences in Blenheim is being accurately represented.
- Regular monitoring of groundwater, rainwater and public water supplies for all agrichemical residues.
- Monitoring of spray drift deposition in specific sensitive areas of concern.
- Development and adoption of a quick, simple standardised spray plan and spray diary software that incorporates information from a proposed spray plan plus the actual spray programme. This would be submitted electronically and include other relevant information such as equipment used and sensitive area identification. The adoption of this approach would improve agrichemical use analysis, council knowledge and investigations.
- Collate spray diary information for at least five years to enable information to be used as part of a future observational study of the health of the Blenheim population.
- Increase agrichemical exposure knowledge of medical professionals and encourage suspected incidents to be reported.
