Long-term Effects of Sewage Sludge and Farm Slurries Applications (repost)

Previous seminars organised by the working party under the auspices of the EEC Concerted Action have been devoted to the evaluation of the nitrogen, phosphorus and organic matter content of sewage sludges, almost invariably over the twelve month period of application.

Depending on the type of sludge they have been shown to be useful sources of nitrogen, phosphorus and organic matter for grass, cereals and in land restoration in terms of improving the physical properties of disturbed lands. However, distance from the treatment work severely limits the radius of operation. Whereas it is of value to farmers within reach of the works, the impact which it makes nationally on reducing the annual fertilizer bill is very small.