Sponsored by the European CropProtection Association and the England Catchment Sensitive Farming Delivery Initiative

Good management of soil and handling areas is key to keeping chemicals out of water. Here the Voluntary Initiative's Patrick Goldsworthy explores best practice for filling – and cleaning – sprayers.

About 40% of the pesticides that reach water come from pesticide handling areas.

As just a few drops of chemical on a foil seal are sufficient to cause pesticide levels in excess of the EU Drinking Water standard along 30km of a stream, it is worth investing thought, time and money in pesticide-handling areas to keep water clean. There are two main options or a combination of both. First, a dedicated area within a farmyard. Second, carrying out filling and cleaning operations in fields.

The critical challenge is to devise a pesticide handling operation that ensures no concentrate, diluted spray or washings reach water. The system has to provide clean, efficient filling practices, sprayer washing – inside and out – as well as dealing with container washings.

How do you minimise point-source contamination?

Yard-based systems

Aim to have a system which catches all water that may contain any trace of pesticide and directs it to a holding tank from where washings can be safely disposed.

Pay attention to drainage and slopes within the filling area, and seal any cracks or joints. Ideally, edges should be raised with a small concrete or brick bund to stop water leaving the pad and more importantly to avoid extra rainwater adding to the volume of washings that need disposal. The lip will also discourage additional traffic that could carry pesticide residues elsewhere on the farm.

Disposal of washings may be by specialist contractor off the farm, through a lined biobed or by spraying on to farmland (subject to what your groundwater permit allows). When creating such a system, pay attention to logistics, such as location of chemical store and water supplies to minimise time and transport.

Bayer’s Cherwell study identified the importance of operator skills. Paying attention to container storage, drips and splashes as well as reviewing the filling location helped prevent 99% of pesticide losses from the farmyard. This, and similar experiences from other European countries, resulted in the pan-European TOPPS (Train the Operators to Prevent Pollution from Point Sources) project which has produced a wealth of useful material for sprayer operators.

A good operator can cut pesticide losses from farmyard filling by 99%.

Field-based systems

Filling and washing down in the field is perhaps the lowest-cost system as it uses cropped land to catch any chemical spillage. Ensure the washing operation does not result in the overall application rate exceeding that permitted for the crop.

The chosen area should be sited at least 10m from any surface water, such as a ditch or watercourse. Also it should not be sited directly over a field drain.

Avoid waterlogged, compacted or frozen soils. The filling locations should be changed regularly to avoid compaction and any risk of residue build-up. Roads, farm tracks and gateways should be avoided as they tend to be too close to watercourses or storm drains.

Portable bunds, or spill trays, can be used in field or yard. However, care is needed to ensure all washings are returned to the spray tank for spraying out.

Filling in the field is a low-cost system but locations should be changed regularly.

How can a biobed help?

UK environment agencies fully support lined biobeds as a means of dealing with washings from pesticide-filling areas. A mixture of straw, soil and peat-free compost is very effective at retaining and degrading pesticides. Residues can be reduced by up to 100,000 fold.

Biobeds need waste exemption from the Environment Agency, must be lined and need careful management including topping up the biobed mixture each year and completely refilling every 4-6 years.

Construction costs can vary from under £1000 where farm labour adapts an existing site to over £5000 for a new bespoke filling area. However, the England Catchment Sensitive Farming Delivery Initiative (ECSFDI) may assist with grants in some catchments.

Well-constructed biobeds are very good at retaining and degrading pesticides but need careful management.

BIOBED CHECKLIST

• Environment agency approval
• Located away from watercourse, spring, well or borehole
• Size (surface area) calculated to allow for rainwater and washings
• Impermeable liner
• Irrigation site for biobed liquid
• ECSFDI grant availability

MORE INFORMATION ON BIOBEDS

• Environment Agency Guidelines
• Biobed design manual
• Best practice guide – Biobeds
• ECSFDI grants

Filling areas and regulations

UK environment agencies seek to be pragmatic on handling areas. However, they can – and will – issue anti-pollution works notices if there is evidence that on-farm activities are leading to pesticides reaching water.

Besides being designed to protect against spray solution or washings reaching watercourses, a well-designed filling area should have:

• Easy access to pesticide storage
• Waist-high work surface for easy handling and measuring
• Area for draining, segregating and storing rinsed pesticide containers
• Clean water storage tank or water supplied via a double check valve.
• Drip tray or portable bund
• Spill kit (cat litter, dust pan/shovel, brush etc).

WHAT TO AVOID

• Filling on hardcore, gravel or compacted soil
• Farm drains and watercourses
• Trip hazards
• Filling the sprayer from streams, ponds, etc

Now take the test on pesticide handling or view the Academy on water stewardship.