Sprayer handling areas and biobed systems

Transcription

1 Sprayer handling areas and biobed systems Steps to limit point source pollution Rosanna Dollman England Catchment Sensitive Farming Delivery Initiative

2 Background High levels of some pesticides have been found in surface water In UK water companies now need to mix or treat water to comply with the EC Drinking Water Directive Sprayer use, and in particular pesticide handling areas, can be a significant source of water contamination. The Water Framework Directive identifies priority substances and the need to meet good ecological status thus indicating a further need for compliance.

3 Catchment Studies In UK, Germany and Sweden 20-70% pesticide load in surface water catchment is derived from point sources UK - River Cherwell study % of catchment pesticide load originated from concrete handling/washdown area

4 Sources of Farmyard Pesticide Pollution 8 % 28 % 12 % Spillage while mixing Tank Rinse Water Foil Seals 17 % 10 % 25 % Mud from tractor wheels Tractor exterior washings Spillage of container washings Results from Year 1 Aventis Cherwell Study Bayer CropScience Cherwell Study

5 Pesticide in mud mg/kg Front Rear Sprayed headland Unsprayed headland

6 Benefits from a handling site review

7 Benefits from a handling site review

8 National Sprayer Testing Scheme - Results Number of tests up to 22 nd September 2003 Over 30,000 tests completed so far Tested and Passed % failure rate - all corrected during test Of the above 50% passed without any work needed Main failure points The remainder needed work done The main causes of the work needed were; Leaks and drips 33% Nozzles inaccurate 20.4% Hose condition 14.9% Pressure gauge inaccurate 13.9%

9 Working routines to minimise contamination Wash down away from the yard, keep sprayer clean Ensure sprayer is well maintained. Triple wash, drain and do not invert empty containers Provide spill kit for leaks, drips and spillages Avoid spraying when the soil is very cohesive Spray headlands last Store sprayer under cover

10 Portable Bunds & Splash catchers

11

12 What is a biobed, how does it work?

13 What is a biobed in UK trials? A hole in the ground filled with compost mix. It receives the liquid draining from a sprayer filling area and has an impermeable liner with a coupled drain for disposal as irrigation / reuse. 2 trialled systems: 1 2 composted mix 50% by volume straw, 25 % soil, 25% peat free compost and grass - turfed over (direct or offset) filled with friable sandy loam soil, not compacted with grass - turfed over

14 Biobed System Components 1An area (bunded) where the sprayer stands 2Drainage from that area to a biobed 3The biobed 4Drainage from the biobed either direct to the soil or to a designated disposal area

15 Biobeds - Function, location and size How do they work? By locking up the pesticides and then providing conditions for enhanced microbial degradation of the active ingredients over time Location A biobed can be sited independently from the loading area, taking account of local drainage, access, groundwater risks, contours etc. Size Where a 24 m, 3000 l sprayer has been used then 5 x 4 x 1 m deep bed has been satisfactory, though local rainfall and frequency of use will influence final size. Biobeds should always be at least 1m deep

16 Which mixing / loading surface? - UK early small scale assessment Concrete Tarmac Crushed stone Soft pavement Pesticide in Biobed drainage was 0.1% of that in concrete run off Grass/soil Biobed

17 Indirect Lined Biobed with irrigation area area Bunded area area Collection Tank (1500 l) (1500 l) Trickle irrigation over biobed Turf biobed BIOBED Irrigation to vegetative area by area by drip or sprinkler LINER Pump

18 Drive-over Lined Biobed with irrigation area irrigation area Steel Grid Grid Irrigation by drip drip or sprinkler sprinkler Turf BIOBED Liner Pump

19 OFFSET + BIOMIX Bunded concrete area Final distribution area with drip irrigation(ground water authorised) BIOBED with Drip irrigation Pre biobed tank

20 BIOBED -SOIL /GRASS with Drip irrigation OFFSET + SOIL / GRASS Drip irrigation to GWA area Bunded concrete drained area

21 DIRECT - BIOMIX Drive over grid Final Drip Irrigation Tank -Pre irrigation to GWA area

22 Typical concs. (μg/l) after application Concrete pad to biobed PESTICIDE Days elapsed Isoproturon Concrete Biobed leachate <0.5 <0.5 <0.1 Chlorothalonil Concrete < <0.1 <0.1 Biobed leachate

23 Topsoil v.s. Biomix Concentration µg/l Mean soil Mean Biomix Days after treatment

24 Under construction - Feb 2002 Liner with connected drain 5m 3 Post biobed storage tank 3m 3 pre biobed storage tank

25 Under construction - March 2002 Drip irrigation of liquid from sprayer loading area Biomix in liner with grass turf on top

26 Operational Aspects Water storage - dilution, flow management & biobed moisture Controls - simple pumps with float and time switches Drip irrigation to biobed and to disposal Area Annual Biomix Top-up Winterisation - frost protection Long Term Biomix Disposal - Residues? 9 bulked samples from top 30 cm -ND

27 CSF Advice Workshops held for farmers in priority catchments Funding available under CSF Capital Grant Scheme (50% costs 2850 for biobeds, 1700 for sprayer handling areas)

28 More Information choose Library, then publications then Best Practice Guides, Pesticide handling areas Biobeds Biobed Manual ADAS Gleadthorpe Cranfield University Environment Agency Scottish Environment Protection Agency PEPFAA Do s and Don t s Guide Bill Basford mechbasford@aol.com om