operat iona l condition and the odour again di sappeared. Sli ght o dour problems aga in became ev ident in mid Dece mber and furth er dosin g was carried out for IO days. No dos in g was necessa ry durin g th e fo ll owing eight weeks. The initial dosing program in vol ved 300 kg of the Ac tizyme a nd the quantities purchased by the Water Boa rd were a t a specia l rate of $ 13.80 per ki logra m. In addit ion it was necessa ry to hire a n Actifeeder for the dosing period . The all -up cost for the seven week dosin g program was $4,23 0. If it is necessary to maint a in a ge neral maint ena nce dosing fo r the other I 9 weeks of the wi nter period a t,
say , 2 kg per day, a further 266 kg may be required resulting in a n add iti ona l cost, wit h hire of the Actifeeder, of approxima tely $4000. . All ow ing fo r so me minor dos in g during the summer period a nd continual dosing during the winter month s, it is est im ated that the total annual cos t of the Actizyme dosing progra m will not exceed $ I 0,000. This cost ca n be compared wit h the alternative of installation of a n aerato r on th e pond, the capital cos t, power cos ts a nd mai ntena nce cos ts of which wo uld result in an a nnual cost of between $25,000 and $30,000 .
January 26-30, Florida, USA Geotechnical App lications of Remote Sensing Transmission February 6-8 , New Delhi , India 4th Groundwater Congress February 16-23, Adelaide, SA 8th Aust. Geological Co nvention February 22-27, Monte Carlo, Monaco Mediterranean Water Technology Ex hibiti o n and Conference. February 27-March 1, Singapore Water and Wastewater Management in Asia March ? , Melbourne, Vic. Environmenta l Engineering March 27-28, Florida, USA 6th Internationa l Sym pos ium on Environmental Pollution I April 1-4, Hangzhou, China 2nd Internatio nal Co nfere nce on Small Hydro April 7-8 , Edmonton , Canada 2nd National Co nference o n Drinking Water (Treatment for Organic Conta mina nts) April 9-11, Dubrovnik, Yugoslavia International Symposium on Comparison of Urban Drainage Models with Real Catchment Data April 9-11, London, UK Measuring Techniques for Hydraulic Phenomena April 14-18, Adelaide , SA Engineering Conference, IE Aust April 16-18, Southampton , UK H ydrau lic Design in Water Resources Engineering
Experimental dosi ng of t he sewerage sys tem with 'Actizyme ' has proved successful in controll in g an odo ur problem at the Swan Hill Treatm ent plant at a cost less than est im ated for mecha nical aerati on, a nd has also proved beneficia l in helping clean sewer mains and co ntrol localised odo ur probl ems at pumping stations. Further in vestigation a nd ex perim enta ti on is now required to determine the nomin al dai ly dosage rate necessary, after the slug dosi ng, to control odour problems during th e worst six month s of the yea r. It is a nticipat ed that the ponds will need litt le o r no treatment during the six warmer month s. August 17-22, Rio de Janeiro, Brazil 13th IA WP RC Biennial Conference
CALENDAR 1986-87 January 18-28 , Co nference - Pollution Monitoring and Contro l
Co nclu sion
April 21-24 , Pennsylvania, USA Environment al Geotechn ology
A ugust 24-30 , Canberra , ACT Sed iments Down-Under
April 22-25 , Ostend , Belgium 4th World Fil trat ion Co ngress
August 25-27 , Rio de Janeiro, Brazil Marin e Di posal of Wastewater IAWPRC
April 28-May 3, Perth , Western Australia A WRC National Work shop on Urban Water Management May 11-16 , Brisbane , Qld International Conference Systems Under Stress
Ground water
May 14-15, Lo ndon , UK Sewerage - Va lue for Money May 14-16, Brighton , UK Water for Energy May 15-16 , Madeira, Portugal 7th Europea n Co n ference o n Envi ronmental Protect ion May 21-23, Brighton , UK Condition Monitoring May 28-30, Paris , France Management of Water and Sa lin a tio n Network s June , Jerusalem, Israel Ecology and Environmental Quali ty June 3-6, Basie, Switze rland Pro Aqua - Pro Vita June 10-13, Bournemouth, UK Water Qua li ty Modelling in the Inland Natural Env ironment June 15-26, Beijing, China Inter-Basin Water Transfer
September 7-10 , Minneapolis, USA Distri bution System Symposi um Septe mber 8-15, Karlovy Vary, Czechoslovakia 19 Co ngress International Association of H ydrogeologists Se ptember 9-11, Durham, UK Jet C utting Technology September 15-19, A mste rdam , Holland Anaerobic Trea tm ent - A Grown Up Technology ' September 22-24, Hanover, W. Germany Press ure Surges 1'
November, Bris bane, Qld Hydrology Co nference November 19-26 , Sydney , NSW 56th Anzaas Co ngress ovember 25-27, Griffith Un, Brisbane , Qld River Basin Management December 6-10 , Baltimore, USA Water Quality Technology Co nference
1987 January 14-16, Khon Kaen, Thailand Rain Water Systems March 23-28 , Adelaide, South Australia
July 2-10, Budapest, Hungary 2nd IAHS Scientific General Assy July 14-17 , London, UK World Water '86
A WW A 12th Biennial Co nventi on
April 6-10 , Rome, Italy H ydrology in Perspective
July 17-1 8, London, UK Famine and Drought
May 26-29, San Juan , Porto Rico Water and Sa nitation in Develo ping Coun tries
August 11-13, Adelaide, SA Expansive Soi ls Conference
June 22-25 , Lisbon , Portugal Waste Stabilization Ponds WATE R December, 1985
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