6.2 The Discharge of Agrichemicals into Air
Background and Explanation
Agrichemicals1 are used to control plant and insect pests and fungal diseases, and are relied on in the agricultural sector to protect and ensure a certain quality of product. The application of agrichemicals from ground or aerial sprays can result in spray drift beyond the intended target.
The application of fertilisers, fumigants, animal remedies and sanitisers has been excluded from the definition of an agrichemical. The effects of fertiliser application are addressed in the Water Module. Exclusion of specific reference to these compounds in this section does not mean that effects on air quality from their application are not addressed. Objectionable effects from particulate matter are addressed in the environment thresholds covered in Policy 1 in Chapter 6.1 and the Guidelines for Assessment in Chapter 6.4, where appropriate. Fumigants are addressed in Rule 18.104.22.168. The discharge of agrichemicals can also have other adverse effects that are covered by the issues, objectives and policies in other parts of the Plan.
Effects of Agrichemical Use on Water Quality
One effect of special concern is the effect of agrichemical discharges to water. These discharges can result in contamination of water bodies with hazardous substances and adverse effects on aquatic ecosystems. The discharges can also result in adverse effects on water quality as a result of vegetation along the margins of water bodies being sprayed then decaying, resulting in a reduction of dissolved oxygen in the water body. This has adversely affected water bodies in the Region in the past.
Agrichemical Spray Drift Management in the Waikato Region
A number of agencies have roles and responsibilities for addressing the effects of spray drift. The key enforcement agencies are Waikato Regional Council, Community Health and the Occupational Safety and Health Unit of the Labour Department. Currently these agencies have an informal agreement identifying how they work together.