Envirnment Agency Advice psitin during exceptinal weather Slurry and milk spreading n agricultural land Land spreading f slurry r milk in exceptinal weather cnditins (see belw) can present a serius risk f pllutin. All effrts must be made t fllw the hierarchy f ptins given in this dcument befre spreading takes place. Where land spreading is the last resrt, we wn t recmmend enfrcement f regulatin where slurry r milk is spread t waterlgged, snw-cvered r frzen land, unless the activity has caused r is likely t cause pllutin r harm t human health, and prvided that; existing farm strage meets the regulatry minimum and ther ptins are nt available; there are n imprted materials taking up strage r being spread, and; we have had prir discussin with the farmer. Backgrund This advice is prvided t help ur staff advise farmers n the safe management f slurry and milk waste in exceptinal weather cnditins. The advice nly cvers livestck slurry (which includes dirty water), and waste milk. CGAP 1, the relevant waste exemptins fr spreading milk 2, and the NVZ Regulatins 3, all advise r regulate against spreading rganic manures t land that is waterlgged, snw cvered, r has been frzen fr 12 hurs r mre in the preceding 24 hurs. This is because f the high risk f pllutin t surface water r grundwater. Farmers must understand the imprtance f having at least the minimum strage capacity requirement, as set ut under NVZ 3 and SSAFO Regulatins 4. Hwever, in times f climatic uncertainty this minimum will nt cver all reasnably predictable events, s farmers shuld be encuraged t prvide an additinal level f strage capacity as a cntingency measure. Exceptinal weather may lead t difficulties with milk being picked up frm farms due t access, and there may be limited capacity n farm t accmmdate this. Individual farm businesses have t decide what additinal strage fr slurry beynd the regulatry minimum is apprpriate fr them. 1 Prtecting ur Water Sil and Air, (A cde f gd agricultural practice fr farmers, grwers and land managers) Defra 2009 2 Spreading waste n agricultural land t cnfer benefit (U10) 3 Nitrate Pllutin Preventin (England) Regulatins 2008 (as amended 2013) 4 Water Resurces (Cntrl f Pllutin) (Silage Slurry and Agricultural Fuel Oils) (England) Regulatins 2010 as amended 2013 (SSAFO) Versin 3.5 December 2015 1
Our regulatry apprach In nrmal circumstances there is n need r justificatin t spread slurry r milk t land that is waterlgged, flded r snw cvered, r has been frzen fr 12 hurs r mre in the preceding 24 hurs. Where spreading ccurs during exceptinal weather cnditins we can t guarantee nt taking enfrcement actin, but the weather cnditins can be taken int accunt when staff cnsider if spreading was unavidable. In NVZ areas farmers will be in breach f their Crss Cmpliance respnsibilities. Althugh, we rutinely reprt all Crss Cmpliance breaches t the Rural Payments Agency (RPA), we are nt bliged t. Where a farmer has engaged with us t vercme the situatin as described at the tp f this dcument, we may cnsider it better nt t reprt a breach t maintain a gd wrking relatinship with the farmer. The primary aim is t prevent pllutin and t minimize pssible pllutin incidents rather than t penalize farmers. What are exceptinal weather cnditins? Exceptinal weather cnditins are thse that surpass what is cmmn r usual, r can be reasnably expected. Fr example, a 1 in 20 year event is unlikely t be cnsidered exceptinal, whereas a cnsiderably mre severe event that can t realistically be planned fr can be. It s clear that just having the regulatry minimum strage capacity requirement is nt ging t prvide adequate capacity in all weather related circumstances. Sme farms may nt meet the minimum requirement because they are perating with ld strage systems nt required t meet the SSAFO Regulatins. Fr us t cnsider a case f mitigatin fr exceptinal weather cnditins, a farmer must in the first instance, demnstrate cmpliance with the minimum strage capacity requirement based n their present (rather than their histrical) farming activity. What is reasnable in respect f milk is mre cmplex as weather r civil circumstances (such as strikes) can prevent tankers frm making cllectins frm farms. Hwever, it is reasnable t expect a farmer t have a cntingency plan in place, except fr prlnged circumstances. Enfrcement The abve apprach still allws us t perate within ur stated apprach t enfrcement, please see ur Enfrcement and Sanctins guidance. What actin shuld farmers take? 1. Measures shuld be taken t reduce the amunt f slurry (including dirty water) prduced n a daily basis, such as: Washing dwn a dairy parlur with a lw vlume hse system (0.6 cubic metres per cw per mnth r 20 litres per cw per day), where it wuld nt cmprmise milk hygiene standards. Remving excess dung with a brush r squeegee befre hsing dwn will help reduce the amunt f wash water needed. Keeping animals n straw if pssible, t prduce slid manure (FYM) rather than slurry. Diverting uncntaminated surface water away frm dirty yard areas, and; Versin 3.5 December 2015 2
Keep/mve livestck nt the minimum yard area necessary Install/maintain/repair gutters and dwnpipes, especially n rfs that drain nt dirty yard areas Cnsider cvering expsed dirty yard areas. 2. Farmers shuld cnsider in advance cntingency arrangements fr their business using the fllwing hierarchy f ptins: Mst favured ptins Strage* at the place f prductin; Strage* at the place f use; Dispsal t an ff-site Anaerbic Digestin # plant, r ther effluent treatment plant (including Sewage Treatment Wrks); Strage* at a third party lcatin; Spreading n lw run-ff risk land. * including hire r purchase f apprpriate temprary strage. See appendix # milk can nly g t permitted AD sites Least favured ptins 3. Additinal practical advice n strage and landspreading f slurry and milk SAFETY NOTE: Mixing milk with slurry can increase the risk f lethal r explsive gases, fr example methane, carbn dixide, ammnia, and hydrgen sulphide. Slurry and milk must nly be spread n land with the lwest run-ff risk. Lw run-ff risk land: has an average slpe f less than 3 degrees; des nt have land drains (ther than sealed impermeable pipes); in the last 12 mnths, has nt been pipe drained, mle drained, r sub-siled; des nt have a shallw sil (<30 cm) abve fissured rck; has a sufficient depth and suitable type f sil abve grundwater t prevent pllutin; is nt within a designated grundwater Surce Prtectin Zne 1; is at least 50m frm surface water r a cnduit leading t a surface water, and at least 50m frm springs, wells and brehles where grundwater is used fr human cnsumptin; desn t have cmpacted sil r a sil surface which is capped (e.g. nly spread where the sil is permeable and has a gd structure). Versin 3.5 December 2015 3
Slurry r milk shuld be spread thinly and widely, at an applicatin rate nt exceeding 20 m 3 /ha. A lwer applicatin rate shuld be used if there is a risk/evidence f run-ff that culd enter surface water. N mre slurry must be spread than is abslutely necessary (e.g. t prevent a stre frm verflwing). Where slurry r milk is spread t land, the activity must be regularly mnitred, including checking adjacent watercurses, t ensure pllutin is nt happening and is nt likely t happen. Milk shuld nly be landspread when a U10 waste exemptin has been registered with us. Steve Wds E & B senir advisr agriculture regulatin December 2015 Versin 3.5 December 2015 4
Appendix Advice n Temprary Slurry Strage Intrductin Shrt term extra strage may be prvided n a farm r grup f farms. Optins culd include: Re-using/reinstating disused stres n farms, including tanks reclaimed frm elsewhere; Installing new tanks r lagns; Regulatry matters Farmers shuld check with the Lcal Planning Authrity fr any planning requirements, making clear that this is a temprary arrangement. Fr temprary installatins we can cnsider reduced requirements fr slurry strage cmpliance with the SSAFO Regulatins, as described in the guidance belw. Farmers must de-cmmissin all temprary facilities as sn as the current difficulties are reslved. If farmers intend t retain the stre fr lng term use it must be re-assessed fr full SSAFO cmpliance, and planning apprval (if that is apprpriate). Farmers must prtect the H&S f all users. HSE sheet AIS9 prvides advice n safety fencing. Practical matters If a farmer needs new r additinal permanent strage, then it needs careful planning, e.g. t avid wasting mney. We anticipate that earth bank lagns, lined lagns r pssibly slurry bags will be the mst likely installatins fr temprary strage. Fr shared facilities: Farmers will need t cnsider any bisecurity risks; Regulatry psitin Versin 3.5 December 2015 The management arrangements, and where the ultimate respnsibility lies, must be agreed between the parties and written dwn; Farming rganisatins may be able t help t brker shared facilities. Facilities that stre slurry must nrmally cmply with the SSAFO Regulatins. Hwever, the full requirements can be waived fr stres that will be used fr less than twelve mnths. Temprary stres are expected t meet the requirements set ut belw. Requirements The Envirnment Agency must be ntified befre cnstructin. Temprary strage must nly be cnsidered where existing facilities are inadequate. Each individual lcatin must be agreed with us (althugh generic designs may be used). Tanks, liners and slurry bags must be installed t manufacturer s instructins. 5
The base f earth bank lagns must be abve the water table it is recmmended that there is at least ne metre f clay subsil beneath the prpsed base. A trial pit is required t cnfirm the depth f the clay layer; the resulting hle must be backfilled and puddled in. Liners must be used where there is any dubt abut sil permeability. Lwer grade liners shuld suffice fr temprary strage (prvided the site is nt a high grundwater risk area). Use higher grade liners fr high risk areas. (See als permeability and liners belw.) Careful initial mnitring must cnfirm the integrity f the stre. Site stres at least 10 metres frm watercurses and land drains, and 50 metres frm grundwater surces. Temprary trial trenches are recmmended if there is any dubt abut the presence f land drains. Permeability and liners Basic sil suitability can be assessed using hand texturing r a jar settlement test (see belw). There are a wide range f liners available fr lining strage lagns. Plastic liners such as plythene r PVC are widely available and generally cheaper than the butyl rubber alternatives. The thickness f liner used needs t be apprpriate t the particular n-site cnditins (site sensitivity, sil prsity and s n). Cnstructin Industry Research and Infrmatin Assciatin (CIRIA) recmmend a minimum f 1.5 millimetre thickness fr liners, but this is fr liners expected t perfrm fr several years. Liner thicknesses in the range f 0.5 t 1.0 millimetre thickness shuld be suitable in mst cases fr temprary stres. Where sheets have t be jined t cver a large area, the supplier can advise n minimum thickness and methds t ensure that jints are prperly sealed. Thin liners are mre susceptible t puncturing, s they must be laid n tp f apprximately 50 millimetres f sand, r a getextile membrane. Take extra care during installatin f thinner liners. Treat sil with weed killer prir t installatin t prevent puncturing frm belw. Abve grund strage Unless earth banks are fully engineered, filling earth bank stres abve the riginal grund level is best avided. In any case, a 750 millimetres freebard must be maintained. Versin 3.5 December 2015 6
Sil clay cntent tests By Masn, P A (1992) Farm waste strage: guidelines fr cnstructin, R126, CIRIA, Lndn (ISBN: 978-0-86017-352-6). G t: CIRIA Reprt 126 Versin 3.5 December 2015 7