Pesticides - Best Practice Guides


Pesticide Handling Areas and Biobeds

Why Pesticide Handling Areas are Important

At least 40% of surface water pollution by pesticides may come from the pesticide handling areas. Water is vulnerable from tiny splashes and spills that occur when filling the sprayer and when rinsing the container. Inappropriate wash down, cleaning and disposal activities can also have significant adverse environmental impact. Just one dropped foil seal can contain enough pesticide to contaminate 30 km of stream. In one study it was possible to reduce the pesticide contamination coming from the handling area by 99%. A key step to achieving this change was to review the site and the surface used for filling and wash down activities.

Pesticide users and sprayer operators must therefore not only look carefully at the design and surfaces used in the handling area, but also their own practices so that we can do more to protect water from accidental pesticide contamination.

Reviewing the Site

Siting and design of pesticide handling areas has developed over the years for operational convenience rather than pollution control. New research has shown that the concrete filling area, so typical of many pesticide handling areas, is potentially the worst surface for handling pesticides; things can be made even worse when the water from the concrete pad drains into a local ditch.

Changing the site, its layout and surface to improve the management of waste liquid and run-off can show reductions in pesticide load of 1000-100,000 fold. Under the Voluntary Initiative, all pesticide users and spray operators are being encouraged to review their current sites and to consider solutions and practices which can prevent, control, retain and degrade pesticide residues and significantly reduce pesticide pollution of water.

Keep Water Clean
Prevent spills

Clear up immediately & dispose of waste safely

Planning Ahead

Before making any changes to your existing arrangements you should consider carefully two factors:

1: Local Water Priorities

Establish if and how local water sources may be affected by what you do at your handling area. Advice and information on water quality risks is available from your local office of the Environment Agency. They can also advise you if you are in a Groundwater Protection Zone as well as giving you background information on local hydro-geology. In any event, you should ensure that the pesticide handling area is sited:

  • At least 10m away from any watercourse or vulnerable site;
  • At least 50m away from any borehole spring or well;
  • Away from existing farmyard flash flood routes, rain water outlets and gutter outfalls;
  • Away from farmyard drains and not above any tile or mole drains;
  • Aside from main business traffic routes;
  • On well structured soil with at least 1.6m depth of soil and sub-soil before bedrock;

Ensure as far as practical that any pesticide contaminated water is handled separately from other drainage water. Use a bund (low concrete lip) to keep the handling area water within the area and to keep rain water and other vehicles out of the filling area.

2: Handling Area Purpose

Any handling area should allow the operator to work safely and efficiently, but it is also important that the area contains any contamination. Thus the handling area should collect all drips and splashes and run-off from rainfall. (Note: Any significant spillages should be soaked up and removed for separate disposal). However, the key decision is whether the handling area will be used just for sprayer filling or whether wash- down activities will also take place. If the sprayer is being washed down it will:

  • Increase the amount of waste liquid This means that for some solutions a larger disposal area may be required.
  • Require a Groundwater Authorisation (GWA) All cleaning and wash down operations that do not take place in the crop are regarded by environment agencies as disposal. This means that you require a GWA from your local environment agency. There is a one-off application fee (currently £103) in England/Wales in Scotland there is an application fee (£162) and annual subsistence fee (£132.70). (Note any changes to an existing GWA, such as introducing a Biobed, need to be advised to the local environment agency).

Pesticide Handling Area Solutions

Below, this guide looks at six different solutions all of which have the potential to significantly reduce water contamination when installed and used correctly. All of these solutions are likely to offer an improvement over an ordinary unmanaged concrete pad. A portable bunded area can help trap spills. The use of either a grass/soil area or a biobed can ensure that any pesticides are trapped in a chemically and biologically active area. This means that over time they can be degraded by the processes in the soil or biobed.

Portable Bund

A portable bund with a suitable lip and made from non-absorbent material can be used to trap spills and splashes. The bund can be washed down and then drained back into the sprayer for application to the crop or treated area.



Cheap & Simple

Not suitable for washdown of large application equipment

Ideal for handheld equipment

Bund not proven with sulfonyl ureas

Easy clean up of spills & splashes

May not be practical for regular use

Compatitble with other solutions

Risk of soil contaminated

Grass & Soil 

Move handling area to grass reinforced with a grid or gravel. This is only suitable for filling, mixing and sprayer maintenance. Periodic movement of the area selected is advised. Note: Do not remove top soil when installing grid; a thin layer of gravel may be placed above the top soil to improve surface stability. Not recommended for heavy clay soils due to compaction risks.




May not be convenient for services & sprayer storage

Easy to establish

Not suitable for wash down


Grass/soil will become compacted over time


Not suitable for some soil types - awkward to walk on when churned up

Offset Grass/Soil Disposal Area

Drain handling area to a grass/soil area; the handling area will need to be drained to a sump the liquid from which can then be trickle-irrigated on to a grass/soil surface. This system is suitable for filling, mixing and sprayer wash down.



Low cost

GWA from local environment agency for wash down needed

Suitable for both handling and wash down

Limited capacity


Sump drainage/trickle irrigation will require management

Offset Biobed*

Drain handling area to a biobed*; the handling area will need to be drained to a biobed possibly via a sump. The liquid can then be spread or trickle-irrigated on to the biobed surface. This system is suitable for filling, mixing and sprayer wash down.



Moderate cost

Sump drainage/trickle irrigation will require management

Suitable for both handling and wash down


Drive Over Biobed*

Biobed* with metal grid and support frame. The liquid drains straight through to biobed. This system is suitable for filling, mixing and sprayer wash down.



Ease of management

Major changes may be required to existing handling sites

Suitable for both handling and wash down

Higher costs

Fully Contained System

Full system with sump and tank for storage of all waste water. Liquid waste collected by a licensed waste disposal contractor or a GWA site. Suitable for filling, mixing and sprayer wash down.



No requirement for a GWA

Major changes may be required to existing handling sites

Suitable for both handling and wash down

High cost to build


Careful management of volumes required


High operating cost

* Biobeds
More information on the design and operation of Biobeds can be found in the Best Practice Guide - Biobeds.

Groundwater Authorisation may not be required for lined Biobeds - refer to the Biobed Guide for more details.

The advice in this Guide has been prepared after consultation with the UK environment agencies and leading researchers into pesticide handling areas. Research was funded by Defra, EA, CPA and SNIFFER..
This guide was produced by the Crop Protection Association as part of The Voluntary Initiative.
The Voluntary Initiative is a programme of measures agreed by Government to minimise the environmental impact of pesticides.

(C) Voluntary Initiative November 2004.

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