The storage requirements for liquid fertilisers depend on the number of grades required at any one time, farm topography and logistics.
If spilled, liquid fertilisers can be very damaging to the water environment, whether from accidental spillage, poor management or vandalism the result could be water pollution with legal and financial consequences.
Farmers share a duty of care for siting, use and maintenance, even when the supplier provides the tanks.
Using liquid fertiliser tanks
Ensure tanks, pipework and valves are fit for purpose, ie resistant to corrosion.
Ensure all tank fittings are tamperproof. Lock all valves shut when not in use.
Ensure delivery companies are aware of emergency procedures.
Ensure tank, pipework and valves are in good condition before deliveries are made.
Check tank has sufficient capacity before delivery.
Avoid overfilling.
Maintaining liquid fertiliser tanks
Have tanks, pipework and valves inspected internally and externally, for damage and corrosion at least annually by a suitably qualified technician.
Carry out any necessary remedial work immediately.
Undertake additional checks at the start of the season and when deliveries are made to and from the tank. If in doubt do not use the tank or bowser.
Drain down and flush through all pipework at the end of each season.
Keep a maintenance record.
Permanent storage tanks
All sites must be more than 10m from a watercourse.
Conduct an environmental risk assessment. Advice is available from the Environment Agency in England and Wales or SEPA in Scotland
Construct secondary containment where environment assessment shows a high risk. Use of reinforced masonry or concrete is recommended and provision should be made for at least 110% of tank capacity. Properly designed and constructed earth embankments may be an acceptable alternative. All pipes, valves and sight gauges should be within the containment area.
Tanks must be on a solid, stable flat concrete on a hardcore base to take the full tank weight.
Consider additional stabilisation against high winds for GRP tanks.
Bowsers and mobile tanks
Temporary storage can pose a significant hazard to watercourses. Thus suitable siting is crucial before filling or dispensing. Transport around the farm needs careful consideration. Roadways and tracks must be able to withstand fully laden bowsers passing over or being parked on them.
Ensure bowsers and all fittings are fit for purpose and protected from corrosion.
Ensure bowsers are set down on level, solid ground before delivery is made.
Provide sufficient support beneath parking legs to carry loaded weight without it sinking into the ground or becoming unstable.
Ensure all hatches and manholes form a watertight seal when closed.
Do not move laden bowser unless all hatches, lids and valves are closed and locked.
Open hatches slightly, when emptying bowsers, to avoid a vacuum which could cause the tank to crumple and collapse.
Further information
The AIC has prepared a series of codes of practice for the storage of liquid fertilisers. These can be downloaded from the AIC website
