Discussion on Papers 15–18

MR THOMPSON, Paper 16

Some countries do not have much of a sludge disposal problem because they do not produce sludge. They merely discharge the untreated sewage into the rivers or the sea. At the other extreme, US legislation is now forbidding the dumping even of treated sludge into the depths of the ocean, e.g. from Los Angeles, where it is claimed to be a harmless operation.

The sensible answer must surely be on the basis

of 'horses for courses1. Just as the breeding

of successful horses takes time, so may the improvement to acceptable standards of sludge quality, through trade effluent control and treatment.