Marlborough Sounds Resource Management Plan 10 March 2006 Effluent can be discharged to land by way of any approved system including transpiration fields, spray irrigation, oxidation ponds, activated sewage sludge plants or a combination of these. The discharge to land of effluent and waste from some activities may cause offensive odours, contaminate the soil and groundwater, and smother pasture leading to a significant reduction in the life- supporting capacity of the land. However, with appropriate management some intensive farming effluent can have a positive effect on the life-supporting capacity of land. Effluent from reticulated sewage treatment systems can be discharged either to land or to water. Given the character of the Marlborough Sounds area, iwi relationship with the water of the Sounds, and the significant use of coastal water for marine farming, land disposal of sewage effluent is preferable to disposal to water. However, the steep slope of the land within the Sounds area and predominance of heavy clays may prevent effective local land disposal. Sewage sludge is a by-product of the sewage treatment process. It is usually disposed of to land. Special attention must be given to the disposal of sewage sludge as it contains high levels of pathogens and is therefore a human health risk. Septic tank cleaning and the disposal of sewage sludge is listed as an offensive trade under the Health Act 1956 and requires a licence from the Public Health Service and the Council. Sewage sludge from septic tanks and sewage treatment plants must be disposed of in an approved manner. There are a number of industrial and trade premises located at Picton, Havelock and Rai Valley. The waste produced at these premises is disposed of to sewer systems via the trade waste system or through on-site waste disposal systems. Irrespective of where waste is disposed to waste producers should seek to discharge the minimum amount of waste and understand the adverse effects of their discharge on the health and functioning of the receiving environment. 14 - 4