industrial wastewater fields, with an annual loss by retirement and other causes of about 15% . To date approximately 150 persons have been trained to a basic standard un_d er the Queens land Technic!l l Co rrespondence School course. In line with o ne of th e reco mm endation s of the report , atte mpts are now bein g made in Queens land , to set up and adv isory committ ee on training of both water and wastewater operators, which wou ld endeavour to introduce several levels of training and/ or qualifi cation to suit varying complexiti es and sizes of faci li ties handl ed by operators. Th e Water Qua li ty Coun cil of Queensland has adopted a po licy requiring th at all wa stewater treat ment pl ant s be under the ¡co ntro l of a qualified operator and that such requirement should be included in licences at so me future date. Due to the inadequate number of qua lified operators, th e Council has not yet implemented this policy . WASTEWATER REUSE IN QUEENSLAN D The major reuse of reclaimed municipal wastewater in Queensland is for th e irrigation of golf links, sports fi elds a nd recreat ion areas. This, however, uses onl y a small proport ion of th e wastewater avai lab le, probably no more than 5% of the total State volum e. Although some investiga tions have been made into the reuse of municipal wastewater for power station coo ling water, the cost has not been sufficientl y attractive. By far the largest element in the cos t wou ld be pipeline transport , since the most proba bl e application is for new power stations remote from large urban centres . Th is situation co uld change in the next two decades with the es ta blishment of new major users of process water such as paper mill s and ext ractive industries and th e further commitment of the State' s fresh water resources for agriculture. Certain Queensland industri es reuse their wastewater either as process water or for irrigation. Notable exampl es a re sugar mills, a battoirs and coal mining. Reuse in sugar mills is for was hwater and for suga r cane irrigation, in abbattoirs for pen washing and holding yard irrigation and at several coal mines water for coa l washing is reused after pond settling. Such reuse is es timated to be about 25%. LEGISLATION AND ADMINISTRATION In Queensland, legislative control over wastewater is ves ted in both State and Local Government. The most speci fi c state co ntrol s are the Pollution of Water by Oil Act and the Clean Waters Act. The form er applies only to the discharge of oi l into natural waters. In relati on to offences against illegal di scharges of oil , thi s Act ta kes precedence over the Clean Waters Act. Where wastewater is a mixture of oil and other waste material, an offence may be punishable under either pi ece of legislation . The Clean Waters Act appli es to all other wastewaters with som e nominated exceptions referred to later, and is the major tool used in the State's control of wastewater disposal in Queensland. Loca l government control stem s from the Local Government Act 1936 - 1981, the City of Brisba ne Act 1924 - 198 l and the Sewe rage and Water Supply Act 1949 - 1981 , the fir st two Acts givi ng Queens land Local Authorities power to undertake the function of providing sewerage, the third setting out standard Local Authority By-laws for both sewerage and water suppl y. The principal By-laws associated with wastewater are the fo ll owing Sewerage By- laws:By- law 33 Compulsory and Permiss ible Discharges By- law 34 Prohibited Discharges By- law 35 Conditions of Discharge These By-laws give a Local Authority power to control di scharges . to sewerage systems. Other Sewerage By-laws are aimed at preventing overflows from sewerage systems. Prior to the proclamation of th e Clean Waters Act in early 1973, wastewater disposa l was largely the responsib ility of Local Authorit ies except for some special agreements between the State a nd large indu stries. Thus the Local Authority would decide the degree of treatment necessary for the discharge from its own sewerage system and also th e requirements for wastewater di sposal from private indu stry in its area. Long established industries such as sugar mills a nd abattoirs were, in practice, free to di spose of their wastewaters as they thought fit. The State exercised some influen ce on effl uent stand ard s
• 24 WATER March, 1983
by virtue of State-guaranteed fund conditio~ but this had no statu tory basis. Since 1973, effl uent control has been administered by the Water Quality Council under the Clean Waters Act subj ect to the Mini ster for Local Government. The Act requires that a person occupyi ng premises from which wastewater is discharged to any natural waters mu st hold a licence for that disc harge. Some wastewater discharges are excluded from the licensing requirements, including wastes from vessels di scha rging into tidal waters, effluents from septic tank in stallations usually serving not more than 100 persons, stormwater runoff from agr icu ltural land and certain industria l effluent s where special state industry Acts or agreements refered to earli er a ppl y. A ll discharges to natural waters from Local Authority sewerage systems and from pri vate wastewater systems are subject to li censing under the Clea n Waters Act. Such discharges includ e overflows as well as wastewa ter treatment plant efflu ent s. Wastewater di scharges di sposed of totally by percolation in to the gro.und or by evapotran spiration, even when the weather is wet, are not subj ec t to lice nsin g. Licences under the Clea n Waters Act spec ify max imum volumes and rates of discharge a nd qua li ty a nd may include oth er specia l co nditions. They are subj ect to annual rev iew. By April 1982, there were 188 licences held by Local Authorities and 227 by other orga ni sat ion s co nsistin g of se mi -governm ental and pri va te organi sation s and indu stry. These figures exclude li cences for overflows, that is, they are solely for di scharges from wastewater treatment plants. FUTURE DEVELOPMENTS IN THE WASTEWATER INDUSTRY A considerable proportion of current expenditure on municipal sewerage is for the augmentation of treatment , trunk sewers and pumping systems. The remainder is direted to overcoming the backlog of unsewered a reas, largely in the south-east corner of Queensland, and for ex tending sewerage to new growth areas such as developing tourist regions and mining towns. Increased effort s wi ll be made to ex tract greater effi ciency from existi ng Local Authority treatment systems and to expanding such plant s with minimum capital outlay. The increased emphasis on these matters has been brought about in the last two yefirs by the changed relativity, between the interest rate on loans (that is, the cost of capital) a nd the inflat ion rate. Economic assessments now prescribe that capit al be expended on ly when it is essential to compl y with present regulatory or other unavoida ble requirem ents. Capital outlay for long term needs ca n no longer be justffied on economic gro unds. Hence, systems with lower capital cost but hi gher operation cost will have in creasing vogue. For example , activated sludge treatment plants could be upgraded by increas ing their oxygenation capacity using air or oxygen inj ection , by the use of flow- equalising storage basins or pumpin g equipment , and by pre-treatment by upstream sewers or press ure main oxygenation. Pl ant expansions wi ll be for shorter proj ections than has been past practice . In dustry has never built wastewater systems for as long a design life as has been the practice for municipal work s because, in general industry has not seen the same permanency in activities. However, faced with the same problems in capital outlay as semi-government bodi es, indu stry will be placing similar importance on limiting capital expenditure wherever possible. In summary, practical research to develop a changed approach to was tewater treatm ent and di sposal by both the Local Authorities and private industry is forecast. ACKNOWLEDGEMENTS A ll of the data contained herei n has been o btained by virtue of my employment in th e Queensland Department of Local Government. I thank a ll officers of that Depa rtment who have assisted me in compilin g thi s inform ation, particularly Mr. H . F. Desmond , Queensla nd Director of Water Qua lit y a nd Mr. D . E. Kemp, Executive Engineer of the Water Quality Section of the Department.