DETR 03/99 and WO 10/99 (1 April 1999)
This circular provides advice on the exercise of planning controls on non-mains sewerage and associated sewage disposal aspects of future development so as to avoid environmental, amenity or public health problems which could arise from the inappropriate use of non-mains sewerage systems, particularly those incorporating septic tanks.
If the system proposed is unsatisfactory, this would normally be sufficient to justify refusal of planning permission for a proposed development. An annex sets out the factors to be considered in reaching a decision, including contravention of recognised practices, adverse effect on water, damage to the environment, high water table, liability to flood etc.
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