Silage Pollution and How to Avoid it

Transcription

1 Silage Pollution and How to Avoid it 1998 Crown Copyright - This document is subject to Crown copyright protection & has been reproduced under licence from the controller of HMSO. The user may not supply copies to third parties nor publish / sell this material to others with out written consent of the Controller. The ADLib Version - This document has been reproduced in full & the technical content is the same as the original. Presentation may vary from the original. Contents The problem of silage effluent pollution 2 The causes of silage effluent pollution 3 Action you can take 4 Before ensiling 4 After ensiling 4 The regulations 5 Advice 5 Support from the Environment Agency 6 Who are we? 6 What do we do? 5 Further information 7 Management and contacts 7 (C) Environment Agency,

2 The Problems of Silage Effluent Pollution Silage liquor is one of the strongest pollutants that occurs on farms. Even in very small quantities its effects are devastating. It's at least 200 times stronger than untreated domestic sewage. It kills fish and the tiny creatures they feed on, starving them of oxygen until they suffocate. It can badly affect water abstractions. Just small amounts pollute groundwater, springs, wells and boreholes, endangering public water supplies. Although the number of substantiated silage pollution incidents and serious pollutions are falling (thanks both to farmers investing in improved facilities and recent dry summers), there is no room for complacency. Silage clamps and effluent collection facilities can deteriorate rapidly if they are not properly managed and maintained. Even months after ensilement, problems can occur. Also, remember that the weather can strongly influence the likelihood of silage pollution problems. So, too, can silage additives and silage made at less than 25% dry matter, both of which often create more effluent. 2

3 The Causes of Silage Effluent Pollution Farmers must be aware that silage liquor is highly corrosive - so much so it can actually dissolve cement. The result of it reaching a watercourse can therefore be devastating. The main causes of silage pollution are: Cutting and ensiling grass when it's too wet; the wetter the grass, the greater the problem. Structural failure of silage clamps, tanks and/or pipe work. Silage liquor overflow from effluent tanks. 3

4 The Action You Can Take Do remove or block off any drains under the silo. Do plan ahead for the weather. Do wilt silage to increase dry matter above 25%. Do consider roofing your silo to minimise effluent Before Ensiling Do ensure the location for any field silage making is chosen carefully and is at least 10 metres from any watercourse. Do make sure the effluent tank is empty before ensiling. Do make sure that drains and collection channels are intact and unobstructed. Do check silos annually when empty for cracks, corrosion or other damage Do make sure that rainwater from fields or yard areas is not entering the silo or tank. After Ensiling Do check the level of effluent in the tank daily. Do empty the effluent tank as soon as practicable. Do check that effluent is not escaping around the perimeter. Do check nearby ditches and streams for any signs of contamination. Do keep collection channels and drains unobstructed. Also make sure that effluent is not soaking into the ground around the sides of the silo, where it can contaminate groundwater or enter land drains. Do remember that problems can occur well after the silage is first made. 4

5 The Regulations and Advice The Regulations Since September 1991, any new, substantially altered, or substantially reconstructed silage making facilities have to meet the requirements of the Control of Pollution (Silage, Slurry, and Agricultural Fuel Oil) Regulations A more detailed leaflet is available specifically on the Regulations, but some of the main points are: Silage made in a structure: Silage clamps, tanks and drains must be impermeable and resistant to attack from silage effluent (which is highly corrosive). They should meet BS 5502, part 22, and have a life expectancy of at least 20 years with proper maintenance. Tanks placed partially or fully underground should have a life expectancy of at least 20 years without maintenance, because of the safety risk with tank inspection. The base should extend beyond any walls and include perimeter drains. Effluent tank capacity should be at least 20 litres/cubic metre of silo capacity (up to cubic metres). For larger facilities a further 6.7 litres/cubic metre is required. No part of the installation should be within 10 metres of a watercourse. Baled and wrapped: Baled and wrapped silage should not be stored or opened within 10 metres of a watercourse. Field silage: Farmers intending to enlarge, relocate or commence making field silage (including Ag-bags) must notify the Agency at least 14 days before making it (forms are available), and it must not be made within 50 metres of a water supply source. Advice Specific advice on design and construction of facilities can be obtained from various sources such as: A farm waste consultant. MAFF (Defra) Code of Good Agricultural Practice for the Protection of Water (see FURTHER INFORMATION). CIRIA Report Farm Waste Storage, Guidelines for Construction (see FURTHER INFORMATION). 5

6 Support from the Environment Agency Who are we? The Agency is an independent public body charged with safeguarding and improving water and air quality, and for ensuring that waste management activities do not cause pollution or harm to human health. We are responsible for regulating waste disposal and those industrial processes with the greatest potential for pollution. Alongside pollution control, we are responsible for flood defence, regulating rivers and groundwaters, protecting and improving fish stocks and promoting water-based recreation of all types. We are committed to improving wildlife habitats and conserving the natural environment in everything we do. What do we do? We keep a regular check on river water quality. Anyone discharging effluent into rivers must obtain legal permission from us first in the form of a 'discharge consent'. The effluent is monitored regularly to check that it is up to standard. Our staff are also on call to deal with pollution incidents and the resulting clean-up operations. Although the Agency has strong powers of prosecution, we firmly believe that prevention is better than cure. Our aim is to make everyone aware of the risks of pollution and what steps can be taken to prevent it occurring. Our staff regularly visit a range of premises to see what pollution prevention measures are in place. We are happy to offer guidance and to visit your farm to talk about preventing pollution. It is far better to talk to us about potential problems before undertaking work and possibly making expensive mistakes. We may be able to offer guidance which will prevent a pollution threat from becoming a reality. All water pollution and uncontrolled waste disposal are criminal offences under the Water Resources Act 1991 and farmers who fail in their responsibilities to the environment face substantial fines and clean up costs. They may also face claims for compensation from downstream river users. In addition, it your silage, slurry or fuel oil store presents a significant pollution risk, the Environment Agency can serve a notice requiring improvements to the store - we don't have to wait for pollution to occur. Farmers may also face prosecution for using a store built after 1991 if it does not comply with the Control of Pollution Regulations. The Environment Agency is available to give help and advice at any time. Get in touch with us and take action before it is too late. Make sure effluent collection facilities are adequately maintained 6

7 Futher Information, Management and Contacts Further information The Code of Good Agricultural Practice for the Protection of Water can be obtained free from MAFF (Defra) or the Agency. Farm Waste Storage: Guidelines for construction (CIRIA Report 126) is available from CIRIA, tel The following are available free from the Environment Agency: Leaflets on the Control of Pollution Regulations and other farm pollution issues. A detailed checklist of items that should be covered by a farm waste management plan. The National Farm Waste Management Planning Register of farm waste consultants conversant with up-to-date requirements. Management and contacts The Environment Agency delivers a service to its customers, with the emphasis on authority and accountability at the most local level possible. It aims to be cost-effective and efficient and to offer the best service and value for money. Head Office is responsible for overall policy and relationships with national bodies including Government. Rio House, Waterside Drive, Aztec West, Almondsbury, Bristol BS32 4UD Tel: Fax: lnternet World Wide Web Environment Agency regional offices: Anglian Kingfisher House, Goldhay Way Orton Goldhay, Peterborough PE2 5ZR tel: fax: Midlands Sapphire East,550 Streetbrook Road Solihull B91 1QT tel: fax: North East Rivers House, 21 Park Square South Leeds LS1 2QG tel: fax: North West Richard Fairclough House, knutsford Road, Warrington WA4 1HG tel: fax:

8 Southern Guildbourne House, Chatsworth Road, Worthing West Sussex BN11 1LD tel: fax: South West Manley House, Kestrel Way Exeter EX2 7LQ tel: fax: Thames Kings Meadow House Kings Meadow Road Reading RG1 8DQ tel: fax: Welsh Rivers House/Plas-yr-Afon St Mellons Business Park St Mellons, Cardiff CF3 0LT tel: fax: For general enquiries please call your local Environment Agency office. If you are unsure who to contact, or which is your local office, please call our general enquiry line. The 24-hour emergency hotline number for reporting all environmental incidents relating to air, land and water. ENVIRONMENT AGENCY GENERAL ENQUIRY LINE ENVIRONMENT AGENCY EMERGENCY HOTLINE