The Control of Pollution (Silage, Slurry and Agricultural Fuel Oil) (Scotland) Regulations 2003

Regulation 2(1)(a)

SCHEDULE 1 REQUIREMENTS FOR SILOS

1.  The requirements which have to be satisfied in relation to a silo are that–

(a) it complies with the following provisions of this Schedule; or

(b) it is designed and constructed in accordance with the standard on cylindrical forage tower silos as published by the BS 5502 (parts relating to Cylindrical Forage Towers).

2.  The base of the silo shall, where the silo has retaining walls made other than of earth, extend beyond those walls and shall in all cases be provided with channels so constructed as to collect any silage effluent which may escape from the silo and adequate provision shall be made for the drainage of that effluent from the channels to an effluent tank through a channel or pipe.

3.—(1) Subject to sub paragraph (2) below, the capacity of the effluent tank–

(a) in the case of a silo with a capacity of less than 1500 cubic metres, shall be not less than 3 cubic metres for each 150 cubic metres or part thereof of silo capacity; or

(b) in the case of a silo with a capacity of 1500 cubic metres or more, shall be not less than 30 cubic metres plus 1 cubic metre for each 150 cubic metres or part thereof of silo capacity in excess of 1500 cubic metres.

(2) The effluent collection system associated with silos may, with the agreement of SEPA, incorporate a system of pumps and sumps, together with detailed sizing, pumping and management requirements, designed to reduce the capacity of the effluent tank.

4.  The base of the silo, the base and walls of its effluent tank and channels and the walls of any pipes shall be impermeable.

5.  The base and any walls of the silo, its effluent tank and channels and the walls of any pipes shall, so far as reasonably practicable, be resistant to attack by silage effluent and, where the walls are made of earth, they shall be lined with an impermeable membrane.

6.  No part of the silo, its effluent tank or channels or any associated pipes shall be situated within 10 metres of any inland or coastal waters which silage effluent could enter if it were to escape.

7.  If the silo has retaining walls–

(a) the retaining walls shall be capable of withstanding minimum wall loadings calculated on the assumptions and in the manner indicated by paragraph 15.6.1 to 15.6.3 of BS 5502 (Part 22: 1993); and

(b) the silo shall at no time be loaded to a depth exceeding the maximum depth consistent with the design assumption made in respect of the loadings of the retaining walls.

8.  Subject to paragraph 9, the silo, its effluent tank and channels and any pipes shall be designed and constructed so that with proper maintenance they are likely to satisfy the requirements of paragraphs 2 to 5 and, if applicable, 7(a) for a period of at least 20 years.

9.  Where any part of an effluent tank is installed below ground level, it shall be designed and constructed in accordance with BS 5502 as referred to in paragraph 7(a) so that with proper maintenance it is likely to satisfy the requirements of paragraphs 4 and 5 for a period of at least 20 years.