How close can you go?
Buffer zones to keep spray drift out of field margins and watercourses are due for a rethink. Andrew Blake examines the latest plans
NEW proposals to remove some of the confusion surrounding spray buffer zones have been drawn up. But the recent change of government sees them on hold.
The plans, from a Pesticides Safety Directorate working party, have been approved in principle by the Advisory Committee on Pesticides and are backed by the NFU. They are intended to make restrictions on pesticide applications near water more flexible, explains working party member Dave Arnold, head of environmental sciences with AgrEvo.
However, similar moves to permit a more pragmatic approach to spraying field margins in general remain some way off, says Mr Arnold.
The latest water-related proposals are being considered by ministers, he says. "We are unsure whether the principles will be approved by the new government. But technically we believe they represent sound management practice."
At present statutory labels on some pesticides forbid applications closer to watercourses than an arbitrary 6m (19.7ft). Other products escape similar restrictions, but labels encourage growers not to spray close to field margins.
"The latter guidelines are only voluntary but are designed to avoid unnecessary contamination of the aquatic environment," explains Mr Arnold.
Key to the new proposals is LERAP – Local Environmental Risk Assessment for Pesticides. "This is effectively an on-site COSH* type assessment, taking into account classification of product and local factors."
The latest idea is to classify products as high, medium or low risk according to their potential effect on aquatic life. High risk materials would continue to attract a fixed buffer zone. Low risk products would merit no buffers and medium risk ones could have reduced zones.
"Measures or features that could lead to narrower buffers are still being considered. But they could include dry ditches, reductions in the dose of product applied and engineering controls to reduce drift.
"It has to be stressed that the principle of LERAP has to be approved in the first place, before agreement can be reached on what can or cannot be included.
Other factors which might be taken into account include watercourse size. "For example there may not be the same pressure on big rivers as there is on more sensitive streams.
"The benefits of a local risk assessment would be that farmers and operators would share in the responsibility for protecting the environment."
Providing more flexible guidance on margin restrictions to protect beneficial insects from specific pesticides appears a stiffer task and has not been considered by the current buffer zone working party.
"There are no short answers." That is because the potential problems and risks vary throughout the season, explains Mr Arnold. "The British Agrochemicals Association supports the view that we need to provide more information, not on labels but perhaps through leaflets, to explain the environmental impact of these chemicals."
Width watcher? Variable spray zones to protect watercourses from pesticide contamination would be welcome, says James Lunn.
• More flexibility near water.
• Individual risk assessments.
• Scope to vary buffer zones.
• General margins not covered.