Pesticide handling areas and biobeds

 A well planned, designed and operated area linked to a biobed will allow pesticides to be retained and degraded by a considerable amount 10,000 -100,000 fold reduction  A pesticide h

Pe s tic ide Handling Are as

and Biobe ds

A pre s entatio n fo r farme rs ,

ope rato rs and advis e rs

De ve lo pe d fo r the Cro p Pro te c tio n As s o c iatio n and Ag ric ultural Indus trie s

Co nfe de ratio n by ADAS The as s is tanc e o f the Enviro nme nt Ag e nc y, SEPA &

 High levels of s ome pe s ticides have be en found in

s urface wate r

 In UK wate r companies now need to mix or tre at water

to c o mply with the EC Drinking Wate r Dire ctive

 Spraye r us e, and in particular pe s ticide handling areas ,

c an be a s ignificant s o urce o f wate r co ntaminatio n.

 The Water Framework Directive identifies priority

s ubs tance s and the ne e d to me e t go o d e c o lo gic al

s tatus thus indic ating a furthe r ne e d fo r c o mpliance

Atmo s phe ric

Ve te rinary

me dic ine s

Drainage / runo ff to

s urfac e wate rs

 In UK, Germany and Sweden

– 20-70% pesticide load in surface water catchment is derived from point sources

 UK - River Cherwell s tudy 1998-2000

– Funded by Bayer CropScience (UK) Ltd– 40% of catchment pesticide load originated from concrete handling/washdown area

s ourc e s of c ontamination

drift tank filling ro ads drainflo w was te dis po s al pave me nts

s urface flo w was hings railways

inte rflo w/bas e

Pe s tic ide Pollution

Spillage of container washings

Spillage while mixing

Tank Rinse Water

Foil Seals

Results from Year 1 Aventis Cherwell Study Bayer CropScience Cherwell Study

Typic al co ncre te filling are as

s ho wing

c o ntaminatio n and

run o ff

 Minimis e contamination incidents through good

o pe ratio nal ro utine

– Limit contamination s pre ad from inadve rte nt actions – Minimis e wate r volume s (rain and was hings ) on handling

to collection quantities

Dis po s al

through a licensed disposal contractor

Tre atme nt

Consider a Biobed

Available from

www.s pills ave c o uk

 Whe re s ite allows , filling the s prayer over a pe rmeable

s urface c an be us e ful Natural bre akdo wn o f the

pe s ticide s is achie ve d by micro bial actio n in the s o il

 BUT

– Site >10m away from field drains and watercourses;>50m from springs, wells and boreholes– Prevent soil compaction by use of drive over grid or hardcore

– May need to move site around periodically if compaction occurs

– Avoid use on heavy clay

 A well planned, designed and operated area linked

to a biobed will allow pesticides to be retained and degraded by a considerable amount (10,000

-100,000 fold reduction)

 A pesticide handling area (mixing and sprayer

loading only) may be linked to a biobed without the need for a Groundwater Authorisation from the

local environment agency.(See sprayer washing note on next slide)

 Be s t Practice for tank was hings and s praye r

e xte rio r s urface s is to carry this o ut in the fie ld

– Any washings should be discharged onto the previously sprayed cropped area

– Observing maximum dose for that area – Follow Statutory (Green) Code advice

If s praye r was hdo wn is inte nde d at the pe s tic ide handling are a with dis po s al to land e ls e whe re , unle s s a line d bio be d is be ing us e d, a Gro undwate r Autho ris atio n mus t be

o btaine d fro m the yo ur lo c al e nviro nme nt ag e nc y

 EA and SEPA s upport Lined Biobeds as

s ignificant improvement over current practice

NEW Regulatory advice for England

and Wales from EA

– Groundwater Authorisation (GWA) not required for lined Biobed

– Water from lined Biobed can be “irrigated” or used without GWA

re-– Site will have to be registered with EA in the future but is expected that registration will be free and can

be done on line

– Scotland check with SEPA – Northern Ireland check with EHS

De s ig n, Cons truc tion, Us e and

Mainte nanc e

1 An area (bunded) where the s prayer s tands

2 Drainage from that area to a biobed

3 The biobed

4 Drainage from the biobed

•either direct to the soil

•or to a designated disposal area

 Offset - the sprayer mixing and loading area is

separate from the biobed area

– Features:

• Bunded concrete,

• Slope of 1:100 to silt trap

• Drain - to supply biobed

 Direct - the sprayer mixing and loading area is directly

over the biobed area

– Features

• Direct - bunded

linke d to Biobe ds

 What do the des igns look like?

– Offs et - A separate area, bunded concrete, where the sprayer stands and any

liquids drain to a biobed

– Direct - A drive over grid all

liquids drain directly to the biobed below the grid

 Both des igns may us e

lined o r unlined bio be ds ; but o nly line d bio be ds are

s uitable fo r was hdo wn

-with dis pos al are a

Turf over

Steel Grid

Dis po s al by drip

o r s prinkle r

Line r

 Close to sprayer water filling point, chemical

store and electricity supply

 Away from other traffic / access routes,

footpaths etc.

 Avoiding collecting extra rainfall - check yard

contours, other drain routes and overflow issues

 Separate from other drains / watercourses

(>10m;>50m)

 Groundwater Risks?

300 mm

s ilt trap to pump

c hambe r

W

L

W = Spraye r trans po rt

width + 2 m

L = Spraye r

le ngth + 1.5 m

Co nc re te

pad

Bund

Size - as for offset

Grid - to support total full sprayer weight

Mesh must be removable for biomix annual top-up

Grid size 100 x 40

 Normally a hole in the ground filled

with:

– Either a composted mix 50% by volume straw,

25 % soil, 25% peat-free compost (biomix)

with turf on top

– Or a friable loamy soil with turf on topThe hole may be lined with an impermeable liner -

or not, dependant on system function, soil type, local drains, local environment agency advice etc

 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.

 The biomix materials could be varied from the mix

s ug ge s te d Guidanc e mus t be s ought to e ns ure re quire d prope rtie s e xis t.

 Turf cover over the biomix is vital to encourage the

biologic al ac tivity of the mix and as s is t in the manag e me nt

of the mois ture s tatus of the biomix

 Efficient dis tribution of the water over the biobed s urface is

c ons ide re d c ritic al, drip irrigation is s ugg e s te d at 400 mm

s pac ing

Drip

he ade r pipe Go o d turf gro wth

Sprayer type Overall

length (m)

Overall width (m)

 From offset loading area, install pump in small

chamber, e.g 0.75 x 0.75 x 1m deep.

 Pump, with integral float switch - approx 40 l/min@6m

head, installed to appropriate regulations.

Site all pipe runs for adequate frost protection.

Pipe to optional holding tank or direct to drip over biobed

 Excavate biobed and liner with sealed drain as

appropriate Liner to be 1.5mm geotextile membrane

on specified inner liner and/or sand as detailed.

 Des ign and cons truct grid to ade quate ly s upport

s pray ve hicle and e ns ure s afe o pe rato r us e

– Operator should be kept off biobed surface for functional and safety reasons

– Allow for grid to be removed in sections for annual biomix top-up.

 Cons truct foundations , as appropriate , avoiding

s uppo rt o n bio be d line r if us e d.

 Excavate biobed and liner with s ealed drain as

appro priate

 Liner to be 1.5 mm geotextile membrane on

s pe cifie d inne r line r and/o r s and as de taile d.

See further biobed installation notes

 Biobed can either be a biomix - s traw, s oil and

pe at-fre e co mpo s t, o r lo amy s o il

 Biobed will need lining whe re was hdown is to be

practis e d (with Gro undwate r Autho ris atio n)

 Lining mus t be s eale d to outle t drain e ffe ctive ly

with co ars e filte r o ve r drain inle t, e g 6 mm me s h

 Whe re unlined, ens ure that s ubs oil is

unco mpac te d

 Lining s hould overlap top of s ide batter by

appro x 300 mm the re by pre ve nting unne ce s s ary rainfall re aching bio be d

 Dire ct drain to optional tank or s mall pump chambe r

as be fo re , o r to pump to final dis po s al are a

 Biomix mus t be compos ted for 4-6 wee ks before

us e and e ve nly lo ade d into ho le Ove rfill ho le to allo w fo r e arly s inkag e

 Turf s hould be laid at time of filling to encourage

gro wth Turf do e s no t ne e d to be hig h quality and is laid o ve r the s urface o f the bio mix, wate ring e arly to

e nco urage g ro wth

 Ins tall drip irrigation, hard hos e type bes t, laid onto

the bio be d turf s urface as we ll as the final dis po s al are a, lightly anc ho r drip line s

 Te s t pump s ys tem before us e

 Biobed irrigation will maintain regular

watering of turf and thus control biomix mois ture condition

 Gras s growth will encourage mois ture us e

and thus evapo-trans piration from biobed

 Check weekly for condition and function

Inves tig ate any tendency for waterlog g ing

 Any foliage cut from biobed turf cover to be

mulched over biobed area

 Where biomix is us ed, material will degrade

and level s inks by approx 300 mm per year

 Biomix top-up annually neces s ary

Dependent on turf growth, turf may be peeled back (with adequate operator protection) and new mix added to res tore level, replace turf.

 Soil bas ed s ys tems probably will not

‘s hrink’ as fas t

 Check irrigation function

 Biomix material in the hole will probably have a life

o f 6 -8 ye ars be fo re re plac e me nt o r re cycling

 Re moval of biomix s hould be done care fully (with

appro priate o pe rato r pro te ctio n) to a co nc re te are a

fo r furthe r c o mpo s ting fo r o ne ye ar Re s e arch

s ug ge s ts any pe s tic ide s re maining are fully

de grade d in that pe rio d.

 Drainage from this area s hould be preferentially

ro ute d to the re ple nis he d bio be d.

 Final dis pos al of the s pe nt biomix mate rial mus t

be in ac co rdance with advice fro m lo cal

e nviro nme nt ag e ncy.

 Where drip irrigation us ed, lay hard hos e

pipes at 400 mm s pacing with drippers at around 1.5 l/h flow rate.

– 1-1.5 running hours per day applies 2-4 mm of water, dependant on equipment used

 Set controls , e.g level s witch and any

timers , to achieve this , allowing for override in intens e rainfall

– buffer available from optional tank if installed

 Sprayer loading area - depends on whether

adequate concrete pres ent with bund added or new material - rang e £300 - £850

 Each chamber £140, pump £60

 Biobed, excavation and materials £500

 Liner, if needed with drain £1000

 Drip irrigation to biobed and final dis pos al,

depends on areas £200- £400

 Sprayer vehicle grid - range £2000 - £5000

 Biobed, excavation and materials /

foundations £800

 Liner, if needed, with drain £1000

 Each chamber £140, pump £60

 Drip irrigation to final dis pos al, depends on

area £300

 www.biobeds.info

 www.voluntaryinitiative.org.uk

– choose Library, then publications then Best Practice Guides,

• Pesticide handling areas

 Scottish Environment Protection Agency

– PEPFAA Do’s and Don’t’s Guide

BASIS CPD Points AP/032/034/d =

1AP

NRoSO CPD Points N0340530c = 1AP

Prac tic al Simple

So lutio ns