The making and storage of silage not in bales or bulk bags

This General Binding Rule (GBR) applies to the making and storage of silage other than in bales or bulk bags.

Authorisation level

General Binding Rule (GBR)

Rules

The making and storage of silage not in bales or bulk bags is covered by General Binding Rules. If you intend to carry out this activity, and you comply with the rules set out below, your activity will be authorised. You don’t need to apply to SEPA for an authorisation.

If you carry out an activity under this authorisation you must comply with the rules. It is an offence if you do not comply with the rules.

If you cannot comply with the rules, you will need a different type of authorisation.

General Binding Rule (GBR) for the making and storage of silage not in bales or bulk bags

1. Silage must be made and stored in a silo which—

   1. complies with paragraphs (b) to (g),
   2. if constructed, or substantially reconstructed or enlarged, on or after 1 September 1991, in addition to paragraph (a)(i), complies with paragraphs (h) to (j),
   3. if new (including a silo constructed from used materials), or substantially reconstructed or enlarged, on or after 1 January 2022, has a life expectancy of at least 20 years, with proper maintenance, from its construction, reconstruction or enlargement,

2. the base of the silo must be constructed with channels to collect silage effluent from the silo, and with channels or pipes which must drain any such silage effluent to an effluent tank,

3. the capacity of the effluent tank must be at least—

   1. for a silo with a capacity of less than 1500 m³, 20 litres for every 1 m³ of silo capacity, or
   2. for a silo with a capacity of 1,500 m³ or greater, 30,000 litres, plus 6.7 litres for every 1 m³ of silo capacity over 1,500 m³,

4. where the effluent collection system associated with the silo incorporates a system of pumps and sumps, it must be fitted with an automatic overfill prevention device with a dedicated electrical supply and an alarm,

5. the base of the silo, the base and walls of its effluent tank and channels, and the walls of any pipes must be impermeable,

6. the base and any walls of the silo, its effluent tank and channels, and the walls of any pipes must, so far as reasonably practicable, be resistant to attack by silage effluent and, where the walls are made of earth, they must be lined with an impermeable membrane of 1000 gauge polyethylene or a material of at least equivalent impermeability and durability,

7. if the silo has retaining walls which are not made of earth, the stored silage level within that silo once compacted must be managed so that the retaining walls of the silo are not overloaded,

8. the base of any silo constructed, or substantially reconstructed or enlarged, on or after 1 September 1991 must, in addition to paragraph (b)—

   1. comply with British Standard EN 1992-3:2006(a) and British Standard EN-1-1-2004 +A1:2014 (for concrete bases) (b), or British Standard EN 13108-4:2016 (for hot-rolled asphalt bases) (c),
   2. where the silo has retaining walls made other than of earth, extend beyond those walls and be provided with channels designed and constructed so as to collect any effluent which may escape from the silo and adequate provision must be made for drainage of that effluent from the channels to an effluent tank through a channel or pipe,

   (a) Published by the British Standards Institution on 31 July 2006 (ISBN 0-580-48267-7).

   (b) Published by the British Standards Institution on 23 December 2004 (ISBN 978-0-580-83726-5)

   (c) Published by the British Standards Institution on 28 February 2018 (ISBN 978-0-580-52033-4). 

9. where any part of an effluent tank constructed, or substantially reconstructed or enlarged, on or after 1 September 1991 is installed below ground level, it must be designed and constructed in accordance with the Buildings and structures for agriculture: Code of practice for design, construction and loading, BS 5502-22:2003+A1:2013(d),

   (d) Published by the British Standards Institution on 10 June 2003, last updated in 2013 (ISBN 978-0-580-78768-3).

10. a silo constructed, or substantially reconstructed or enlarged, on or after 1 September 1991, which has retaining walls which are not made of earth, must have retaining walls capable of withstanding the minimum wall loadings calculated in accordance with the Buildings and structures for agriculture: Code of practice for design, construction and loading, BS 5502-22:2003+A1:2013,

11. a silo constructed (including from used materials), or substantially reconstructed or enlarged, on or after 1 January 2022, which has retaining walls which are not made of earth, must have the maximum loadings of the silo visibly displayed on it,

12. a silo, its effluent tank, channels and any associated pipes constructed on or after 1 January 2022 must not be situated within 10 metres of any surface water or opening into a surface water drain which silage effluent could enter if it were to escape,

13. the silo, its effluent tank, channel and pipes must be operationally maintained to be free of any structural defects during its lifecycle,

14. the silo must not be filled beyond the drainage channel,

15. where a silo or effluent tank is to be constructed or to be substantially rebuilt or enlarged—

    1. the operator must give notice to SEPA of the works no later than 30 days prior to commencing the works,
    2. the notice under sub-paragraph (i) must be accompanied by an engineering plan for the works to be carried out,
    3. the operator must retain the engineer’s final sign-off certificate for the works for the lifetime of the silo or effluent tank, for inspection by SEPA on request.

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