Water Journal June 1975

I 1ssN 0310 - 0367 j Official Jo rnal of the AUSTRALIAN WATE R AND WASTEWATER ASSOCIATION

IVol. 2 No.2 - June 1975- Price $1-00 I

An A.P.M. Mill Pond.

Water is life Water is as necessary for papermaking as are forests .

And, like a forest, water is a renewable resource provided man works with nature to conserve it.

Water conservation has always been a feature of A.P.M.'s activities in the company's mills as well as in the fo rests, especially in recent years. Fairfiel d Mill , near Melbourne, for example, has managed by intensive recycling to redu ce the amount of water

it uses to make each tonne of product to about one third of what it needed ten years ago. Thi s is the result of research, constant care, and the installation of advanced fi It ration and reclamation plant. And the improvement is continuing.

At A.P.M .'s mills elsewhere the story is similar maximum possible recycling of water within the plant and puri fication of the used water befo re it is released. At Petrie,

Broadford and Maryvale mills the company has built large aeration ponds to help nature's sunlight, wave action and oxygen recondition the used water.

Nature has responded with an increase in waterfowl and fish life in these areas. We make paper to do things better.

m

Australian Paper Manufacturers Limited.

466

EDITORIAL COMMITTEE Chairman: C. D. Parker Committee: M. Dureau G.R . Goffin F.R. Bishop L.C. Smith Joan Powling R.L. Clisby B.S. Sanders A.G. Longstaff W. Burnett W. Nicholson A. Macoun A.F. Herath Hon. Editor: Publisher: John G. Craig A.H. Truman BRANCH CORRESPONDENTS CANBERRA A.C.T.: A. Macoun, P.O. Box 306, Woden, 2606.

NEW SOUTH WALES: M. Dureau, Envirotech Australia Pty. Ltd., 1 Frederick Street, Artarmon.

VICTORIA: A.G . Longstaff, Gutteridge Haskins & Davey, 380 Lonsdale Street, Melbourne, 3000.

QUEENSLAND: L.C. Smith, 24 Byambee Street, Kenmore, 4069.

SOUTH AUSTRALIA: R.L. Clibsy, C/· E. & W.S. G.P.O. Box 1751, Adelaide, 5001.

WESTERN AUSTRALIA: B.S. Sanders, 39 Kalinda Drive, City Beach, 6015.

TASMANIA: W. Nicholson, 7 Swansea Court, Lindisfarne, 7015.

NORTHERN TERRITORY: A.F. Herath, 59 Allwright St., Casuarina, 5792.

Editorial Correspondence: Hon . Editor, A.H. Truman, C/· Davey·Ashmore Pty. Ltd., P.O. Box 4709, Melbourne, 3001.

Or to State Correspondents.

Advertising Enquiries: John Craig, 'Water' P.O. Box 100, Caulfield East, 3145.

Phone: 211·7978 - 874·2133

CONTENTS Editorial - Winds of Change ...····················~··············· 7 Association News.......................................................... 8 Reuse of Effluent for Agricultural Purposes - P. Jakobsen & R. Wetselaar ............ .10 The Googong Dam - R. E. Goldfinch .......................17 The Dispersal of Alum Sludge G. C.- Cossins.........19 Water Monitoring ........................................................22 AWWA Regional Conference ..................................... 23 Conference Calendar.................................................. 24 New Products ................................................................ 26

COVER STORY The fir st Philips automatic water po llution mon itor in Australia is now in service in the Parram atta River monitoring th e condition of the water at Rhodes .

Install ed by the Philips Scientific and I ndustrial Equipment, it is being demonstra ted to potential cust omers.

The monitor consists of a boat mounted pump moored about ten metres from t he shore and connected to a land based housing which contains the measur ing and calibrat ion equipment .

Automatic electrode cleaning and calibration are features of the monitor which wil l run for a month or longer without attent ion .

Parameters being monitored at Rhodes are acidity and alkalinity , chlorine content , electrical conductivity, the amount of ox idisation or reduction taking place, dissolved ox ygen , t urbidity (suspended sol id s) and t emperature.

The boat pump is connected to thyland ·based housing by electrical leads and hoses which carry the water to and from the pump.

See story page 22 .

Printed by Stockl and Press Pty Ltd .

1

METERS FEEDERS CONTROLS

ACROMET 900 -

POWER & PROCESS WATER TREATMENT POLLUTION CONTROL

DIAPHRAGM METERING PUMPS

A compact, versatile, robust metering pump, totally encloaed, no expoeed moving parts, manual or automatic control. The Ideal pump for accurate metering of water treatment and proceN additive chemicals. Simplex or Duplex with Micro capacity adjustment while in operation, double diaphragm construction, double valving, solution or slurry heads.

Australian designed and manufactured In materials to suit any chemical.

ACROMET -

[!].

•

MINI METERING PUMPS

A low capacity, low cost, sail contained diaphragm metering pump. Capacities to 340 litres per day - preaaures to 690 kPa.

AQUAMATIC -

pH

A total system for pH control comprising detecting section, indicator-control unit and metering pump with servo motor. The Aquamatic-pH control system offers reliable automatic control of pH in water and waste water neutralisation and industrial applications.

ADVANCE -

CHLORINATORS SULPHONATORS AMMONIATORS

The safe simple chlorination system proven throughout Australia in municipal and industrial water treatment, swimming pools, pollution control , food and other manufacturing procesaes.

Low in initial cost and low in maintenance requireme~ta ADVANCE is supported throughout Australia by a unique installation design and replacement unit service.

Automatic Residual Control. Automatic Flow Proportioning. Capacities to 150 k11/hr.

BALL -

VORTEX METERS

Available for gases and liquids in Aluminium, Carbon Steel and Stainless Steel, sizes to 150 mm -diameter, accuracies to ±0.25¾. With readout and control accessories for batching blending .ticket printing, remote rate of flow indication, digital totalising , etc . '

BALL -

LEVEL AND FLOW SWITCHES, PULSATION DAMPERS

Level alarms suitable for any application from process column to sump level control. Flow switches for the simplest to the most exacting control requirement .

No Seals, diaphragms or bellows.

Accessories for heating, cooling, purging, time delay, electric or pneumatic switching .

Available in bronze, steel , stainless, monel, hastelloy.

Pulsation dampers with pressure ratings to 69 MPa wetted parts available in neoprene, Buna-N and hypalon .

BRUNER -

SOFTENER & FILTER CONTROLLERS

BRUNER-MATIC CONTROL CENTRES serve to regenerate water softeners and backwash water filters. Operation may be fully automatic using water meter or time control, automatic' push -button start or manual.

Brunermatlc Control Centres may be used on any size plant and are available with all brine controls.

CHLOR -

SCALE

Developed for the water treatment industry, the Chier-Scale, with integral tare weight ad justment, provides local indication of the amount of ch lorine remaining in a container. The heart of the system is a rugged hydraulic load cell. Chlor-Scale may be fitted with alarm con tacts and 4·20 mA.OC. transmitter for remote indication, record or alarm.

ERDCO -

TOXEX FLAMMABLE GAS-VAPOR DETECTION

Toxex Alarm and Control Systems provide ultra-stable and accurate monitoring of potentially toxic or explosive conditions. Sensing heads with a response time of less than one second may be located up to 10,000 meters from the instrument. Guaranteed reliability for twelve months between servicing, only possible by use of Erdco's long life specially developed humidity immune filament. Single, sequential or multi-point detection and the Erdco patented 'Sniff and Sneeze' for dusty atmospheres.

ERDCO -

FLOWMETERS

A vane type rate of flow indicator calibrated for each application to give a constant accur&cy within 2X even with solid contaminants. Self cleaning nonposition sensitive. AVailable in sizes to 300 mm with alarm contacts and transmitter for remote flow rate indication. Pressures to 17 MPa, temperatures to 177' C.

KATES -

AUTOMATIC FLOW RATE CONTROLLERS

The ideal instruments for the accurate control of flow of clean liquids from a pressurised source. The KATES controls flow rates over a range of 15:1 to within :I;: 1.51. irrespective of upstream and downstream pressure variations and without the need for any other in~ strumentation. KATES controllers are available in various sizes to control flow rates up to 33 litrH-second and in materials to suit most liquids. KATES controllers may be adjusted manually or automatically using pneumatic and electric signals.

KEENE -

METERING EQUIPMENT

"XACTO" MODEL 460 leading the world in metering accuracy by true positive displacement.

Various mechanical, electrical and electronic accessories are available to totalise, batch, blend or package liquids of endless variety.

MODEL 450 Oscillating Piston Meter 20-50 mm stainless, cast iron, bronze, Accuracy± 0 .2%, Respeatability ± 0.3% . also available with batching, totalising and ticket printing accessories.

2

L.E.M. -

DRY MATERIALS FEEDERS & CONVEYORS

LEM auger type feeders and "New-Matlc" conveyors handle everything from grain to ground glua pharmacaoticaf elements. bakery Ingredients and water treatment chemicalo.

MADDEN -

BOILER BLOW-DOWN CONTROLS

The Madden Orifice Meters puts an end to hit or miss intermittent boiler blowdown, it drains from the area of maximum concentration continuously, preventing any accumulation of impurities. It controls discharge precisely with less heat loss and where desired facilitating heat recovery. Orifices are guaranteed for 10 years each orifice plate offers a selection of 17 different blow-down rates.

NIKKISO -

NON SEAL CANNED MOTOR CENTRIFUGAL PUMP

The no leakage pump especially suitable for the prevention - of waste of valuable liquids - ot hazardous conditions due to leakage of toxic or combustible liquids - of pollution from leakage of toxic liquids.

NIKKISO -

CONTROLLED VOLUME PUMPS

High pressure precision plunger and diaphragm controlled volume pumps produced in a computer controlled manufacturing process under controlled atmospharic conditions for the ultimate in accuracy and reliability .-Standard pressure rating 24 MPa, high pressure rating 49 MPa viscosity to 200,000 cps and temperature to 50)• C.

NIKKISO -

HI-POWER PUMPS

Horizontal, single acting plunger pumps with multi~lex cylinders for delivering fluids at high capacities and high discharge pressures.

Capacities to 40 litres per second. Pressures to 440 MPa. Temperatures to 450 degrees Celcius.

PODDY METERS -

MANOMETERS

A range of precision single-column, 'U' tube and Inclined (Draught Gauge) Manometers. The Poddy range incorporates gauges specifically designed for the gas industry with non-spill and anti-blow off feature.

PODDY METERS -

FLOW SYSTEMS, FLOWMETERS

Orifice Flow Systems for both water and gas flow, both fixed and portable flow gaugas are available for these s)'Slems, the latter being particularly suited for application in heating and airconditioning.

SINGER -

AUTOMATIC VALVES

Th·e Singer Series 106 automatic valve is suitable for control of all variables encountered in water and alr reticulation systems as well as in the form of combination valves to perform more than one function . The Series 106 is available in sizes to 400 mm. Pressure reducing , Pressure & Surge Relief, Check, Solenoid control, Rate of Flow control , Level control and Pressure sustaining .

VANTON -

FLEX-I-LINER PUMP

The Flex-i-liner is a sealless plastic pump having an ideal application in the transfer of liquids in the electroplating industry or where the nature of the liquid causes difficulties with packing glands etc. The Flex-i-liner is seij-priming and will develop vacuums up to 660mm Hg . The Flex i-liner is non-agitating , the gentle pumping action prevents chu rning or foaming making it ideal for the pumping of emulsions and the like. Capacities ere available up to 3 !~res/second and pressure ratings to 340 kPa.

VANTON -

CHEMGARD AND SUMPGARD CENTRIFUGAL PUMPS

Chemgard centrifugal pumps are designed to accommodate any commercially available mechanical seal. They are heavy duty pumps in which ALL wetted parts are plastics. Capacities to 32 litres/second. pressures to 60 metres head and temperatures to 149'. C. Sumpgard -vertical pumps - incorporate many Chemgard feat~res complete freedom from metallic contamination heavy-duty all plastic pressure lubricated sleeve bearings designed and spaced for shaft stability and vibration-free operation.

VANTON -

GAUGE GARDS & STRAINERS

Pressure gauge activator-isolators available in PVC and polypropylene with neoprene, hypalon and viton diaphragms. Pressures to 1.0 MPa, temperatures toss• C. Strainers.to 80 mm in PVC and polypropylene with mesh sizes 5-60.

VANTON -

FLEX-I-PLUG ALL PLASTIC VALVES

Combines no-pressure-drop design of gate valve with flow control features of a globe valve plus corrosion and abrasion resistance of plastic. Manually and Pneumatically controlled 15-50 mm. PVC and polypropylene with neoprene, hypalon or Viton plugs.

VANTON -

"FLEXI" FILTER SYSTEMS

" FLEXI" pump-filter systems are ideal for plating solutions and for all chemicals where leakage is costly or dangerous and metal contact must be eliminated . They are specially recommended for dependable filtration of:- Chl0rides, fluoborates, acids and' alkaline solutions - Chromium, nickel, zinc, cadmium, gold, silver, platinum, palladium and similar plating solutions.

- Corrosive chemicals where no contact with metals is permitted.

ACROMET PTY. LTD. 12 FURY COURT, SOUTH CLAYTON

P.O. 8Ok <191, CLAYTON, VIC. 31e8.

PHONE 5"'7 3077

5/181-183 SOUTH CREEK RD. DEE WHY, N.S.W. 20119 PHONE 982 8055

PERTH-Henderson Instruments Pty. Ltd. 81-4477 ADELAIDE-F.R. Mayf.leld Pty, Ltd, 87-3161 BRISBANE- Queensland Meters and Controls Pty, Ltd. 58-3533 HOBART-E lectrical and Engineering Supplies Pty, Ltd, 72-8833 LAUNCESTON- Electrical and Engineering Suppf(es Pty, Ltd, 31-6155

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CHEMICAL ANALYSIS BY COLOUR COMPARISON Chemical analysis can be complicated. Comparing colours is simple and quick - a task that even an unskilled operator can perfor~.

Tintometer have taken more than 300 analytical tests and produced complete and simplified procedures and instructions for carrying them out by visual , colorimetric methods.

-¡¡

The instrument used is the Lovibond 1000 Cominexpensive and robust with interparator changeable discs carrying permanent glass colour filters.

For each test a solution is produced from the sample, if the sample is not already in liquid form.

A reagent is used to produce colour in the solution.

Then the colour is compared and matched against the filters on the disc , and the quantitative answer read direct.

'

SELBYS SCIENTIFIC LTD Melbourne 544 4844

Sydney 888 7155

Brisbane 71 1566

Perth 21 9431

Adelaide 51 4651

Hobart 34 4166

I .

C h OICe. donkin Frontrunners in gas compresSion and control

Two major Australian public authorities recently chose Bryan Donkin compressors for their new sewage treatment plants. The equipment is being installed at the South Eastern Purification Plant of the M.M.B.W. at Carrum, Victoria and the Lower Molonglo Water Quality Control Centre of the National Capital Development Commission in the A.C.T.

acked by over a hundred years of manufacturing experience, the Bryan Donkin Company is dedicated to continued development of gas handling technology.

For more information, contact the Australian machinery age.its Hawker Siddeley Brush Pty. Ltd.

~ HAWKER SID DELEY BRUSH PTY LTD Incorporated in NSW

VIC . 262-284 He ide lberg Road , Fairfield , 3078 . Tel. 489 2511 . N.S .W. 12 Frederick Street , St. Leonards, 2065 . Tel. 4398444 .

QLD .193 Mary Street , Bri sban e , 4000 . Tel. 21'2926 . W.A . 113 Kew Street , Welshpool, 6106 . Te l. 617944 .

Hawker Siddelev Group supplies mechanical, e lectrical and aerospace equip ment with world-wide sa les and service.

4

6009 HSBD

Rocla awarded its 20th prestressed concrete pressure pipeline in Australia Since 1952 over 2000 km of Rocla prestressed concrete pressu re pipes have been used in important projects throughout Australia and 15 other countries. Now Townsville City Council has chosen Rocla for the Ross River Dam Water Supply Pipeline. Talk to Rocla's major contracts people about the ever increasing advantages of Rocla prestressed concrete pressure pipes.

Rocla Industries Limited-Major Contracts Division

.Rocla RPCP/3372

Branches in all States

5

THIS SYSTEM

... monitors this stream's water quality automatically Phillps have turned a concept into a reality with this automatic water monitoring system based on continuously operating. fully automated stations Running unattended for a month or more. these stations are actually automatic laboratories. measuring any desired combination of pH. redox . pCI or other ,on act1v1ty. conduct1v1ty dissolved oxygen. temperature. and turb1d1ty You determine what you mean by water quality . and this system wril measure 11 Besides automatic measurement. each station also provides automatic sensor cleaning .. automatic calibration .. automatic sampling automatic emergency

storage automatic In-statIon recording automatic alarm and even automatic data transmIssIon to a central Processing Unit The key to the system Is its flexibili ty Data may be provided In virtually any form. and transmitted by line or radio link Each station Is engineered to the application The central Data Reductor can be as simple as a chart recorder ... as sophisticated as a computer

By cutting manpower costs to the bone. the Philips system Is now on-stream, making real-time water quality management a reality-at lowest applied cost.

If you r job is controlling the quality of surface water, drinking water, or domestic/ industrial effluents, you should get the full story now.

Contact : Pollution Monitoring Department, Philips Scientific & Industrial Equipment, G.P.O. Box 2703, Sydney 2001. or phone your nearest Philips office.

Inside view of an automatic water monitoring station installed

by Philips in Sydney.

Scientific and Industrial Equipment

PHILIPS 38.2486

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FEDERAL SECRETARY: R.F. Goldfinch, P.O. Box 359, Canberra, 2601 BRANCH SECRETARIES: Canberra, A.C.T. D. Butters, Cf- Dept. of Housing & Construction Phillip, A.C.T., 2606 New South Wales: Dr. D.T. Lacey, 16 Fairy Dell Close, Westleigh, 2120.

Victoria: R. Povey, C/- S.R. & W.S. Commission, 590 Orrong Rd., ¡ Armadale, 3143.

Queensland: A. Pettigrew, P.O. Box 129, Brisbane Markets, 4106.

South Australia: M .C. Sanders, C/- Engineering & Water Supply Dept.

Victoria Square, Adelaide, 5000.

Western Australia: B.S. Sanders, P.O. Box 356, West Perth, 6005.

Tasmania: P.E. Spratt, Cl- Fowler, England & Newton, 132 Davey St., Hobart, 7000.

Northern Territory: N.R. Allen, 634 Johns Place, Nightcliff, Darwin, 5792.

EDITORIAL

Winds of Change A decade or more ago, Harold McMillan, one time British Prime Minister spoke of "the winds of change sweeping through Africa" . In a completely different context the winds of change have been capriciously sweeping through Australia.

The winds, I refer to, are the current attitudes and concerns of the general public and the multi disciplinary professions involved in t he water and wastewater fields.

Traditionally our industry has been conservative in its desire to safeguard public health, provide continuity and effective low cost operation of water and wastewater utilities and these objectives are still of paramount importance.

However, in the past, lack of depth in project investigations often coupled with financial constraints have meant that while primary objectives are met, there may have been some detrimental aspects introduced to the environment Systematic examination of the options available and analysis of beneficial and detrimental effects that can result from each option, may permit a decision to be made that is in the community's overall interest.

The current format used in Environmental Impact Assessments is in fact a sophisticated check list of possible factors and variables and a formal method of reporting with due specificity and selectivity on particular issues.

Thus while some of the detrimental effects which may or may not be irreversible should be highlighted, subtle and important sociological community issues may be missed .

How do we achieve these community objectives, certainly not by abdicating to laymen - but I believe by achieving a carefully designed programme of public participation in which a selected cross section of a community joins the technical study team in discussing the objectives of the project, encouraging co-operation so that controversial issues can be resolved, and an open flexible planning process maintained which responds to people rather than format.

Thus the process of public participation should help to bridge the credibility gap; by using the virtues of openness, flexibility, persistence, candour and hopefully removing emotion and politicking from the decision making process.

The mind boggles at the thought of how environmental assessment and public participation may have varied the Egyptian Aswan Dam project - an ecological disaster, and the possible ecological victory gained when the United States Government deferred the Alaskan_ Pipeline until an impact assessment was done.

All the above help to make for the improved quality of life, western nations strive for, however one cannot help but reflect on the profligacy with which we squander our natural resources - in particular water for domestic, industrial and agricultural purposes. Year by year per capita consumptions grow with attendant increases in headwork costs which ultimately the community has to pay for.

Surely the time cannot be far away when basic water allowances will be allocated with a punitive charge for excessive use of water. Perhaps in this throw-away world the community cannot respect and restrict their use of water when it is only $7 or $8 per tonne and less acceptable socially than beer ateighty times the cost.

Two A.W.W.A. Tours for 1975 A.W.W .A. "World T our" - October, 1975. , A.W.W .A. " Inda-Australian Work shop."

(See A ssoci ati on New s for further d eta il s.)

Perhaps as members of the Association we should be looking to playing our part in guiding the community more positively than in the past.

F. R. BISHOP

7

re

ASSOCIATION NEWS

INSPECTION - JOHN LYSAGHT PTY LTD Some 45 branch members inspected the wastewater treatment facilities at the John Lysaght (Australia) Ltd., Westernport, Cold Strip Mill. .

It is interesting to note that the capital cost of the wastewater treatment facilities was $5m. compared with a total capital cost of the plant of $92m.

The Association wishes to express its thanks to Messrs. Hull, Taylor and T hompson and to all the other emp loyees of John Lysaght who helped to make the two visits such an outstanding success.

ADDRESS BY R.W.G. EVANS VICTORIA The first half of 1975 has been a very lively one in Victoria A.W.W.A. circles, as one might expect with Alan Strom at the helm. A varied and extremely interesting program has played to packed houses which we're sure are in no way related to the exotic pre meeting fare.

The year's activities got away to a fine start with the February visit to Lysaght's factory at Hastings. Discharge of tradewastes to our most sensitive waterway (Westernport, not the Yarra, for other states' ben efit ) requires a very sophisticated system of pretreatment, and the large group present were most appreciative of the opportunity to view the scheme at close quarters.

Bill Evans, Senior Executive Engineer from 'the Rivers' (State Rivers & Water Supply Commission), led off the formal program with a most informati ve review of the trials and trends in overseas wastewater treatment practice. Although Bill's tour included Pari s (he says for the I.A.W.P.R. Conference) hi s slides were confined to technical aspects of his trip, much to the chagrin of those mem bers who remain co nvinced that no-one (but no-o ne) visits Paris to inspect Wastewater Treatm ent facilities.

The April meeting was addressed by Dr Graham Frecker, newly appointed Environmental Project Director with the Ministry of Conservation. Another large attendance was kept on their toes, by a very thoughtful presentation of overall environmental objectives.

Graham, previously MMBW project leader for the Port Phillip Bay environmenta l study, emphasized the need for careful consideration of all aspects of any environmental project involving diversion of basic resources (water etc.).

And to round off a very successful series, we were pleased to welcome to the May General meeting our senior executive from the land of milk and money, Federal Secretary Reg Goldfinch. Reg developed in very able manner the story of the history of Canberra's water supply and the development of the new Googong Water Supply System to ¡ a large and appreciat ive audience.

Victorian notes for th is edition would not be comp lete without mention of the pleasure we all have in the appointment of Committee Member J. S. (Sam) Rogerson to the position of Commissioner of the State Rivers & Water Supply Commission . Those who recal l his organisation of the last Federal Convention in Melbourne, will need no reassuring that this is a particularly apt appointment.

Sam, with Nance, is presently enjoying a wel I earned long service leave overseas and will no doubt be relieved to hear that there are no moves afoot in our local "Caucus" for spill. No need to hurry back, Sam.

8

I feel that it is almost unnecessary to mention the talk given by Bill Evans as a record number (approximately 70) attended this meeting. I feel certain that none of the members present were disappointed with the talk and the discussions that followed, and will endorse my suggestion that Bill be asked to present another talk at a later date .

ADDRESS , BY Dr. G.B. FRECKER The very high standard set by the first speaker was maintained by Dr . Frecker who spoke to a near capacity audience on 3rd April.

His theme of "Environmental Studies" was obviously of great interest to the audience who joined in lively discussion after the talk .

If this high standard can be maintained we are in for a "vintage" year so make sure you don't miss any future meetings.

The Spring Conference at Lorne - the weekend of October 10th-12th, looks like being a real pleasure even if it is discussing "Urban Discharge Problems". (See the Conference Calendar for details.)

CANBERRA The 24th General Meeting of the Canberra Branch was held on 3rd June, 1975. Guest speakers were Mrs. C. Settle and Mr. A. Hatfi eld of the Department of Environment and Conservation.

The speakers recently attended the following conferences: W.H.O. Regional Conference on Water Quality in Manila U.N. Committee on National Resources in Tokyo O.E.C.D . Water Management Sector Group 7th W.M .O. Conference The speakers discussed current world trends in the fields of water quality , Water management and National Resources Management. A film entitled "Stormwater Pollution Control" was also shown.

NEW SOUTH WALES The regional conference was addressed

by Sir John Fuller on March 15th at Orange.

The theme of the conference - "Decentralisation and Water" - was a tremendous

A.W.W.A. SUMMER SCHOOL CANBERRA, 1975 Copies of the two-vo lume set of lecture notes are available. Please submit cheque for $20 payable A.W .W .A .

Summer School and mail to: Hon . Secretary, A .W.W.A . Summer School, P.O. Box 359, CANBERRA CITY, A.C.T . 2601 Payment includes packing and postage within Australia .

'Success capped August all ~ ho

and the conference programme was by a great barbecue under t he warm sun beside Carcoar Dam. Thanks to participated.

In April , Sir John Fuller, M.L.C ., Minister for Planning and Environment, N.S.W. and Leader of the Government in the Legislative Council, officially opened the new Water Conservation Faci lities at Shell's Clyde Refinery. Members were ab le to gain an excellent idea of t hi s ultra-modern plant when Graham HolmesWa lker of Shell addressed our Ju ne 18th Genera l Meeting. The new install ati on effect ively closes the water loop at t he refinery and includes a massive mul tice ll coo ling tower, a filtratio n plant, and a f ull y automated biological treatment p lant for sour water and other contaminated wastewaters.

"Environment 75" is one of the main events of the year and all of us seem to be involved with this conference/exhibition in one way or another. It takes place at the Sydney Showground between the 1st and 6th of July and we hope to see a large number of interstate visitors there.

Future meetings planned for t he N .S.W. Branch are:23 July : Annual General Sydney.

Meeting,

University

of

20th August : General Meeting M .W.S . and D.B. "Recreational Uses of Water Supply Reservoirs" by Prof. Burton of the University of New England.

19th September : Annua l Dinner at Crows Nest Businessmen's Club. Also in September is the delayed Hawksbury Agricu lt ural Col lege's Res identia l Schoo l on "The Treatment of Wastes from Processing and Manufacture of Food and Agricultural Products" .

15th October: Meeting at M.WS. and D .B. Paper by Mr. Nichols of D.U .R. D. on the "National Sewerage Programme" .

12th November: Meeting at M.W.S. and D .B. Panel session on "Computing in the Water and Wastewater Industry" .

5th December : Christmas Party at the Kirr ibi ll i Ex-Servicemen's Club.

ANY NEWS ITEMS? Manufacturers are invited to send news of any new products, projects or services for inclusion in the new product and projects section, see page 26. Editorial should be around the 250 to 350 words, photographs of the products would be welcome.

Post to John Craig, P.O. Box 100, Caulfield East, Vic., 3145.

QUEENSLAND

2. RECENT ACTIVITIES

On Saturday, 24th May, 1975, a Field Day was held by the Queensland Branch of the A .W.W.A. Members from as far afield as Dalby a路nd Maryborough attended the function, together w ith w ives and families . The day was high ly successful from both a social and. viewpoint .

Attendance was technical approximately 60 persons.

During the morn ing, we inspected the Brisbane City Council water treatment plant at North Pine Dam, which has recently been completed to augment the B.C.C . water supply. Having seen this project during its co nstruction , members found it most interesting to see the treatment plant in operation and the completed structures.

After a picnic lunch in the grounds of A.P.M ., members inspected the Water Pollution Control Plant recently built by Pine Rivers Shire Council, which also proved most interesting and informative .

We are indebted to Mr. G . Cossins, Brisbane City Council, the Pine Rivers Shire Counci l and their co nsulting engineers for their courtesy in allowing the inspections and to A .P.M. for the use of their pi cnic grounds, and also to Alan and Margaret Pettigrew 路who made the necessary arrangements.

REGIONAL CONFERENCE At t he May Committee Meeting, it was resolved that the Queensland Branch should organise a regional conference to be held on the Gold Coast probably on the weekend, 3rd-5th October, 1975. John Ryan is f urther investigat ing t hi s proposal and it is hoped to obtain papers from local Gold Coast members. Further information will be forwarded to members by the Secretary when f i nal arrangements are known .

SYMPOSIUM 75 Wastewater - What to do with it Papers del ivered on 17th April 1975.

Copies are available from Queensland Branch Secretary at a cost of $6, plus 50c postage.

D .J. Lane, Chief Chemist , and K .J. Shepherd, Engineer for Water Resources both of the Engineering and Water Supply Dept . addressed a Branch meeting on 28th February on "Water Resources - Quality and Quantity." Mr. Lane spoke on developments in overseas water pol lution and research laboratories, whilst Mr. Shepherd spoke on recent developments in water resou rces measurement and planning for S.A. and the organisation of the newly created Water Resources Branch of his Departmen t.

Prof. J.W. Holmes and Dr. G. Allison addressed a meeting on 30th May on "Isotopic Investigations of the Water Reso urces of the South East." During the years from 1959 to the present time C.S.I.R .O. ' and latterly Flinders University have attempted to measure the actual evapotranspiration from grassland and forestland (P. Rad iata). 路A successfu I outcome of this work indicated as early as 1965 that evaporation from forest so exceeded that from grassland that groundwater recharge annually was insignificant beneath the forest. By contrast recharge beneath grassland was shown, at one site to be about 65 mm yr-1 . Subsequent careful application of tritium hydrology techniques has proved that' beneath grassland' rechargr can be in the range 40-180 mm yrdepending mainly upon sub-soil and deeper lithology.

Present work is directed towards more intensive isotope studies and very detailed micrometeorology of the forest canopy to elucidate the importance of intercepted moisture retained on the canopy of the trees. It appears to evaporate up to twice as fast as the rate of evapotranspiration when the canopy is dry.

3. Future Activities A Branch Meeting will be held in August on a subjedt to be fixed.

On 31st October, Prof. Schwerdtfuger, Mr. Lee and Mr. Robin will give an address on "Weather in Monarto."

SUSTAINING MEMBERS 1974n5 CANBERRA National Capital Development Commission Directora~e of Engineers

NEW SOUTH WALES SOUTH AUSTRALIA 1. OFFICE BEARERS President Vice-President Immediate Past President Secretary Treasurer Committee

Mr . K.O. Trevarton Mr. D.J. Lane Mr. A.D.R. Marlow Mr. M .C. ~ant;!~rs Mr. A . Glatz Mr. R.L. Clisby Mr. A .O. Greenhough Mr . A .G. Shepherd Dr. J.M . Dwyer Dr. C.D. Fuller Mr . R .C. Williams

Laporte Australia Ltd .

Water Conservation & Irrigation Commision Metropo litan Waste Disposal Authority Gosford Shire Council John Thompson (Aust.) Pty . Ltd. Maritime Services Board Health Commission Public Works Department Sharples Stokes Pty . Ltd. Atomic Energy Commission Braemar Consolidated Pty. Ltd .

ACI Technical Centre Concrete Industries (Monier) Ltd. Council of the City of Blue Mountains Council of the Municipality of Dubbo Envirotech Australia Pty. Ltd .

Gatx-Fuller Australasia Pty. Ltd .

The Hunter District Water Board John Lysaght (Aust.) Ltd. Lightnin Mixers Pty. Ltd. M.W .S. & D . Board Permutit Co. of Aust. Pty. Ltd.

Rankine & Hill Rous County Council Southern Riverina County Council Toledo Engineering Pty . Ltd. 路.Tubemakers of Aust . Ltd . Wallace & Tiernan Pty : ltd .

VICTORIA VICTORIA: Commonwealth Department of Works State Department of Health State Rivers & Water Supply Commission State Electricity Commission Melbourne & Metropolitan Board of Works Ballarat Sewerage Authority Gee long Waterworks & Sewerage Trust Latrobe Val ley Water & Sewerage Board Gutteridge, Haskins & Davey Camp, Scott & Furphy Garlick & Stewart C.S.I.R.O. Candy, Scroggie & Drummond Pty. Ltd. William Boby & Co . (Aust.) Pty. Ltd. James Hardie & Co. Pty. Ltd. Dandenong Valley Authority I.C.I. Research Laboratories Davy-Ashmore Pty. Ltd. E.P.C.O. Pty. Ltd. Water Science Laboratories Pty. Ltd .

Humes Ltd. Caldwell Connell Engineering Environmental Protection Authority

WESTERN AUSTRALIA Metropolitan Water Board

QUEENSLAND I.C.I.Australia Ltd. Water Supply & Sewerage Department Recla Pipes Pty . Ltd .

James Hardie & Co. Department of Local Government Pettigrew Engineering Co. l>ty. Ltd .

Underhill Day & Co. Pty. Ltd. Concrete Industries (Old.) Ltd. Irrigation & Water Supply Commission Co-Ordinator General's Department of Public Works Evans Deakin Ltd .

Evans, Anderson & Phelan Dunlop I.B .C. Pollution Prevention Engineering Pty . Ltd .

Beaudesert Shire Council A lbert Shire Council

SOUTH AUSTRALIA Coca Cola Bottlers Pty. Ltd. Cooper & Sons Ltd. Ellis & Clark Pty. Ltd. Engineering & Water Supply Department Fairey Austra lasia Pty. Ltd. - Culligan Division Humes Ltd. I.C.I. Aust. Petrochemicals Ltd. James Hardie & Co. Pty. Ltd. F.R. Mayfield Pty . Ltd. S.A. Meat Corp.

Petroleum Refineries P.G.H. Industries Ltd. Recla Concrete Pipes Ltd. S.A. Brewing Co. South Aust. Housing Trust S.A. Institute of Technology .

Our thanks to these companies and instituti_ons for their generous support.

9

REUSE OF EFFLUENT FOR AGRICULTURAL PURPOSES by P. Jakobsen and R. Wetselaar CSIRO, Division of Land Use Research Canberra Reuse of effluents is promoted by 1) a scarcity of water, and 2) by the frequent comparatively high nutrient content of effluents, which can be harnessed in plant production and which otherwise can lead to harmful eutrophic effects in natural water ways. As water becomes increasingly scarce in many places in the world, much research is directed towards its efficient usage. The major means is recycling, and the ultimate aim is a method so refined that sewage effluents can be used for human consumption.

At present, sewage effluents are used for industrial purposes, particularly in the paper manufacturing industries (Ref. 1) and in agriculture. Werribee farm and smaller plants in Victoria and South Australia are the major centres for evaluat ion and use of sewage effluents in Australia. At Werribee, in 1969, more than 450 000 cubic metres per day, contain ing 700 mg/I organic materi al and J ,200 mg/I mineral salts, were appl ied over 4,550 ha of pastures supporting up to 19,000 catt le and 50,000 sheep (R ef. 2). In South Australia sewage effluents are discharged over recreational grou nd s, horticultural crops and pastures (Ref. 3).

General requirements for optimum use of effluents for irrigation are: 1. Evapo-transpiration of the cropped land is greater than the natural water supply.

2. The effluent is available when needed.

3. The effluent is of sufficient quality to ensure continual and long-term use.

4. Drainage effluents can efficiently and rapidly be removed.

This paper deals mainly with the third requirement, i.e. with the quality of effluent and its short- and long-term effects on agricultural systems.

Ideally the effluents shou Id contain only those nutrients that are required by the crops co ncerned, in amounts which sat isf y optimum growth . Both types and amou nts of co urse, vary from crop to crop, and the relationship between supp ly and up take is dependent on soi l type and clim atological factors. In practice, an efflu ent often contains either an excess of p lant nutrients and /or undesirabl e constituents that may have a detrimental effect on soil or plant.

Fortunately, plants usually tolerate a wider range of concentrations ·of elements than man and animals. They may in fact act as screening buffers in the uptake of elements such as fluoride , molybdenum, vanadium, and copper where there are narrow limits between nutr ition and tox icily. In general , a detrimental effec t ca n be due to an excess o f : 1.

2.

3.

4.

5.

6.

7.

Major nutrients· (e.g. nitrogen and phosphorous).

Minor-nutrients (e.g. copper and zinc).

Non-esse ntial elements (e.g. cadmium and lead).

Salts.

Pesticides Detergents, and Pathogenic bacteria and viruses.

Numerous factors and th eir interactions must be stud ied to fully understand the short- and long-term impact of these parameters on soil, plant, animal , and man. In t hi s paper we attempt to b ring out the more f und amental aspects, with emphas is on the metals. as their presence appea rs to decide the restrictions on the use of eff luents.

For a more exhaustive delineation of the limits of derogatory and beneficial effects of chemicals in irrigation water the reader is referred to "A Compilation of Australian Water Qu ality Criteria" by Hart (Ref. 4 ), and "Water Quality Criteria" by McKee and Wolf (R ef. 5).

10

MAJOR NUTRIENTS

Nitrogen and potassium are taken up by crops in q~antities ranging from 100-200 kg ha· 1 , wh ile on ly 20-40 kg ha· of the elements phosphorous, magnesium, sulphur is co nsum ed. Surplus app licat ion of nitrogen may resul t in lodging of grain crops or lower quality of fruits (citrus, avocados etc.). Stonefruits usually suffer delay in matu ration, and co lours may not develop in ripening apples (Ref. 6). Factors gu iding the efficient application of nitrogen to crops and t he effects of its losses to the environment have been dealt with in several recent reviews (R ef. 7, 8 and 9). Excess potassium, ca lcium, or magnesium does not usua lly pose problems; large excesses of phosph ates may, however, have derogatory effects , particular ly on p lant uptake of zinc and iron.

MICRONUTRIENTS AND NON-ESSENTIAL ELEMENTS

The fate of an element in the agricultural system depends main ly on its chemica l properties, and these are to a great ex t ent reflected in the periodic table. Many minor elements be long to t he firs t transition se ries, w hich comp ri ses scandium, tita nium , vanad ium, chromi um, manganese, iro n, coba lt , nicke l , copper and zinc. The order specifies progressive filling of the inner 3d subshell of the atoms with electrons, and consequently these elements have many physical and chemi ca l propert ies in common . They all form insoluble hydroxides and sulphides, important factors in reducing their toxicities. Their halides and sulphates are solub le, and they readily form co-o rdination compounds and c rysta ls in which other transition metal ions can be su bstituted to form extens ive so l id so lutions.

Copper

Copper, better th an any other element of the series, illustrates the biological behaviour of the above micron utrien ts, i.e. it read ily reacts w ith amino ac ids and proteins and forms very stable chelates, it is a very versatile and active cata lyst, part icularly wheni ncorporated into the protein of an enz yme, and it has versatility as an electron acceptor or do nor as it readily exists in both monovalent and divalent forms (Ref. 10). T he more important copper enzymes are I isted in Table 1.

A n app licat ion rate of 7-14 kg CuSO 4 ha· 1 to the so il wil l usually meet the dem and of crops for severa l yea rs ( Ref. 11 ).

Concentrations of 50 mg/I Cu and above in effluents to plants and trees may cause toxicity, and trees may suffer leaf burn and "die back" of growth (Ref. 12). Alleviation of t9xicity may occ ur through prec ipitation of copper ions as carbonates in neutral or alk aline soils, adsorption of hydroxy-cupr ic ions to clay minerals, and formation of organic compo unds (R ef. 12 and 13).

Hydroxy-c upri c ions are adsorbed to clay particles according to the Freundlich adsorpti on isotherm equation : , where y is the copper adsorbed per unit adsorbent y = ac 1 and c is tRI! concentration of Cu in the so lu tion, and a and n are constants depend ing on soil type and pH. Adsorption increased with in creasi ng pH ( Ref. 14). Copper as an organically com plexed anion is less t ox ic than the cation (R ef. 15); the latter reacts readily with am ino, imino , and sulphydry l groups in amino ac ids and proteins (Ref. 10 and 16). The movement of t he co mpl exed anion also is less restricted, conseq uent ly it may easily move out of the growth zone of plants.

Zinc

Z inc is act ive in several enzy me systems, part icul arly these involved in aux in production so that zinc deficiency may be detected by reduction in long itud inal and latitudinal growth of shoots, apart from the chl orotic and necrotic spots which 'usually develop on the leaves (R ef. 12 ). High phosphate co ncent ra t ions may, due to the antagonistic effect of phosphate to zinc, agg ravate zi nc defic iency and al lev iate its toxic ity. Antago ni stic effects of other ions (e.g. iron) may d o likew ise (Ref. 12, 13 and 17). For some species high co ncentrations of zinc may be present in the soil before tox icity is evident; fo r example Leeper (R ef. 13) reports that exchangeable zinc concentrat ions (1 / 10 N HCI extractant ) of 400 mg/I zinc in th e upper 150 mm layer of soil at a sewage farm in Victoria did not cause toxicity to perennial rye grass. However , Karlson (Ref. 18 ) claimed that tox icity occurred to pl ant growth in Sweden when th e zinc co ntent of the soi l was about 300 mg/I exchangeab le.

Z inc toxicity may be alleviated by increasing soil pH by liming, particularly using magnesium ca rbonate, as the magnesium and zinc and 0.72 ions are approximately of the same size (0.66 respectively), and consequently may become interchanged on the ionic crysta l lattices. Z in c is not as strongly chelated as copper (Ref. 12).

$.

i

Nickel

Nickel is ana logous to copper in strength of chelation but otherwise behaves generall y like zinc. Its availabi lity decreases with increasing pH. About 50 mg/1 Ni in the plant has been reported to be toxic (Ref. 13 and 19); this concentration was recorded for plants growing in soils containing organic matter with 2000 mg/I Ni. Nickel may be re leased from weathering of ultra-basic rocks, and the so il derived has been reported to contain up to 8,000 mg/I, of which 100 mg/I was extractab le by acetic ac id (Ref. 20). Nicke l appears to be less avai lable to p lants at soil pH values above or below 6.5 to 7; it is mobilised in soi ls following flooding and aeration, and it is more read ily ava il ab le in poorly drained so i ls (Ref. 16 ). It interferes with plant absorption of iro n, and suff icie nt iron may reduce the phyto-toxicity of n icke l (R ef. 16). Nickel does not appear essential for plants or animals.

A proposed zinc equ ivalent of toxicity is given by : Total Toxicity= Zn+ 2Cu +8N i, implying that copper is twice as toxic as the. same amount by weight of zinc, while nickel is eight times as tox ic (R ef. 21). For sensitive crops tox ic metal additions to agr icu ltu ral soils should not exceed zinc equiva lents equal to five per cent of the cation exchange capacity of the unamended soil at pH 6.5 (R ef. 22).

Iron and Manganese Iron and manganese are often present in the soi l in quantities so great that extraneous additions are not li ke ly to affect natural conditions sign ificant ly, except in cases where the pH may be altered. 'Waterlogged (i.e. rice cu ltures ) or acidic condit ions may release ferrous and manganese ions in toxic quantities ( Ref. 13).

Cobalt

Cobalt is an essential element for certain algae (Ref. 12) and is required for nitrogen fixation in legum inous plants and forms part of vitam in B12. It appears more toxic to p lants than nickel, and an app li cation to the so il of 2 kg Co ha¡ 1 may decrease yields. Toxicity is characterised by intraveina l ch loros is, which later degenerates into necrosis, and tips of leaves become red co loured and the rootmass decreases. Toxicity may be alleviated using l ime and large quantities of phosphate, the reby precipitating coba lt as insolub le phosphate compounds (Ref. 12 ).

Chromium

Chromium is not essent ial for plants, although they usual ly co ntain about 0.03 - 1 mg/I. Irrigat ion with sewage wastes has raised the chromium contents in p lants 3-10 times of those of the control (R ef. 16 ). Hexavalent chromium is cons idered more toxic than t ri va lent chrom ium, and both inhibit nitrification of ammonium in soi l. Chromium is antagonistic to lead (Ref. 16). A deficiency of the former in humans may cause abnormal glucose metabolism. (Ref. 16.) Chromium, coba lt, and nicke l are poorly adsorbed from ord in ary diets by animal s and humans and consequent ly little toxicity may occur (R ef. 23).

Vanadium

Vanadium is considered essential for some algae, and the fungus Aspergillus niger (R ef. 12). It appears useful in contro lling levels of cholesterol in the blood, and it may also prevent dental car ies (Ref. 19). Plant growth may be decreased by high levels of vanadium, but the vanadium content of the above-ground parts of the p lant is usuall y less t han that of the roots. Toxicity transferred to animals and hum ans has not been recorded. The availabi lity of vanadium is greater in poorly drained so il s (R ef. 16). The rema in ing elements of the ser ies' titanium and scandium have been little exp lored with regard to toxic ity.

Molybdenum and Cadmium

Molybdenum and cadmium belong to the second transition series, where higher oxidation states tend to be more stable than in the first transition series and belong to the same groups as chromium and zinc respectively. Molybdenum is so strong ly oxidised that it occurs in the soil only as the anion Mo02/4-. As such it reacts with aluminium and iron in acid soils. Newly precipitated ferric hydroxides may occlude molybdate (Ref. 12 and 24). The availability of molybdenum in alkaline soi ls may be so great that "luxury uptake" occurs, which may result in toxicity for cattle (Ref. 13). Imbalance of Mo and Cu may occur when forage contains more than 5 mg/I Mo; this may result in stunting of growth and bone deformation (Ref. 19). Allev iation of molybdenum toxicity can occur through app lication of CuSO 4 , sulphates or man~nese fertilisers, or by improving soil drainage, and Mo0 4 ions are of similar si ze, and competitive uptake w ill occur.

High phosphate levels in the soil will tend to increase molybdenum uptake ( Ref. 12 and 25). Many soils in Australia, New Zealand and Scandinavia are deficient in molybdenum, and legumes, crucifers, and citrus are most affected (Ref. 26). Molybdenum is involved in the reduction of nitrates by plants, and its defici,!: ncy symptoms are similar to those of nitrogen deficiency.

soi¡

Cadmium is not considered essential for plants, but up to 1 mg/I has been found in plants where ¡sewage effluents have been applied over a period of 60 years (Ref. 27). The uptake of cadmi um is great ly influenced by soi I type and plant spec ies and even parts of the plant; thus only 12-18 per cent of the cadmium in cereal plant tops may be translocated to the grain (Ref. 28). Cadmium is highly toxic to man, and it has been associated with hypertension, ateriosclerotic heart diseases, proteinuria, kidney damage, anosmia, and testicular atrophy. Zinc has been shown to protect the body against the toxic effects of cadmium (Ref. 27).

Soils at Werribee having received sewage effluents for about 60 years have attained a total Zn/Cd ratio of 100 against 47 of the control. This ratio was largely reflected in the plant (Ref. 27 ). This seems to indicate that cadmium could have migrated out of the top soil faster than zinc, thus providing a self-regu lating anti-tox ic mechanism . The logarithmic concentration of cadmium adsorbed to soil has been found to be_directly proportional to the pH of the so il.

No difference .was observed using calcium carbonate or magnesium carbonate in increasing the pH (Ref. 29), indicating that no significant interchange occurred between t he similar ions calc iu m or cadmium on the crysta l lattice of calcium carbonate.

Mercury

Zinc, cadmium, and mercury belong to the same, group in the 1st, 2nd, and 3rd transition series. Inner subshells are fi ll ed with electrons, and outer she lls on ly are involved in chemical bind ing.

The zinc group is in many aspects similar to the group of alk aline earth metals (magnesium, ca lcium, and strontium ). The respective individual members have similar radii : zinc: 0 .72 A, magnesium : 0.66 A cadmium: b.96 A, ca lcium: 0.99 A mercury: 1.10A,strontium: 1.15A The elements of the two groups have the va lency 2. The chemical binding of the alkaline earth metals are, however, more ionic in character than those of the zinc group, where the nuclear charge is less protected by the electrons in the d sub-she I Is than those in the p sub-shel ls of the alka line earth metals. This results in bonds of more covalent character of the elements in the zinc group.

The ionic potential (charge/radius) of the zinc group decreases in the order Zn Cd Hg. T)le firmness at which the metals are bound to exchange sites varies in the reverse order; the addition of mercuric ch loride to soils results in the immediate fixation by organic matter and the clay fraction (Ref. 16). The order of decreasing electronegativ ity of the metals is Hg Cd Zn. Methylation, a commo n metabo lic reaction , is be lieved to occur only with metals of sufficient electronegativity. Thus, mercury is methy lated w hereas the higher activation energies and greater ease of hydro lysis of cadmium and zinc seems to prevent methylation (Ref. J6). Mercury may be methylated in presence of decay ing fish (Ref. 30 ).

11

Alkyl (methyl and ethyl) mercury compounds may cause mental retardation, abnormalities of chromosomes, cerebral palsy, coma , and death. Aryl (phenyl) mercury compounds and inorganic sa lts are less dangerou s as they are degraded fairly rapidly in the I iver and kidney and excreted as inorganic mercury. In alkyl mercury the mercury is firmly bound to the carbo.n atom which resists its break-down (R ef. 31). Mercury has a strong affinity for sulphydry l groups in proteins, and when bound to these may interfere with membrane functions, and the functions of mithochondria and lysosomes within the cell (Ref. 31 ).

Plants usually contain less than 0.5 mg/I mercury (Ref. 16).

However, marine algae may accumulate mercury in concentrat ion up to 100 times that of the surrounding seawater. The concentration of mercury may further be increased in animals consuming the algae and in successive trophic levels (Ref. 31).

Diffusion of methyl, ethyl or phenyl mercury fungicides through the seed-coats of seeds may result in high mercury content of plants (Ref. 16).

Lead The toxity of lead is similar to that of mercury in that it readily reacts with sulphydryl groups. Its effects have been observed particularly in the en zymes responsible for the synthesis of heme, a constituent of hemoglobin and cytychromes. In acute lead poisoning kidney functions are impaired, leading to excessive excretion of phosphates, causing hypophosphatemia. Encephalopathy and edema may also occur. The above co nditions are usually revers ible when the tox ica nt is removed. Chron ic nephr itis and death of 165 people is estimated to have occurred in Queensland, when water from tanks co ll ected from roof tops with lead pigments was continuously consumed (R ef. 32).

The uptake of lead in plants depends more on soil and plant type than the supply of lead in the soil. Lead increases in the plant with maturity and cont inues to do so even when the plant rema ins dormant (Ref. 19). Lead does not seem essential for biolog ical life (R ef. 19 and 32).

Molybdenum, Arsenic, Selenium, Boron and Fluoride Of these anions, molybdenum was mentioned ear lier in relation to its position in the periodic table. Arsenic is in the same group as phosphorus, and selenium in that of sulphur The elements of each re~pective group have many properties in common.

The main source of srsenic in effluents is probably from pestic ides. The pentavalent ¡form. present in wel I aerated soi Is, is far less toxic than the trivalent form. The levels of arsenic in sea-foods are frequent ly in excess of estab lished tolerance levels for th is element, but plants rarely contain more than 1 mg/I of arsenic The primary danger arises from soil part icles attached to plants.

Application of ferrous sulphate, aluminium sulphate, and lime have been reported to alleviate toxicity of arsenic in soils. Any treatment which reduces arsenates is, however, also likely to reduce phosphate concentrations (Ref. 19).

Seleniu m is essential for animals and possib ly p lants (Ref. 33), but narrow limits exist between nutrition and tox icity. Diets contain ing in excess of 4.5 mg/I may result in depressed growth rates and infertility. Levels of 0.40-0.20m/1 appear sufficient ( Ref. 19). Under alkaline, well-aerated conditions, selenium becomes oxidised to se lenates in the soil; these are readily avai lab le to plants, and toxic concentrations may be reached. Barium ch loride is used as a precipitant to reduce the avai labil ity of se lenium in the soil (R ef.

19). Add itions of sulphates, as compet itive ions, appear successfu l on ly where sulphates are in low supply (Ref. 12). The tax icity of the selenates decreases in the following orde r: H 2 Se0 3 H 2 Se0 4 Na 2 Se0 3 Na 2Se0 4 (Ref. 34).

Application of Na 2 Se0 4 at a rate of 0.07 kg ha_ 1 may result in concentrations of Se toxic to livestock, even a year after its application (Ref. 35). The mobility of Se applied as Na 2 Se0 3 is greater in neutral than in ca lcerous so il s, and is intermediate in mobility between Cu and Mo (R ef. 36).

Narrow limits also exist between tax icity and nutrition of boron . and toxicity has occurred using irrigation water conta ining 0.5 mg/I boron (Ref. 12), although somewhat higher limits usua ll y are considered safe (Ref. 4). Additions of 30 kg B ha¡ 1 has caused damage to wa l nut, corn, beans, and potatoes, and part icu larly cereals ( Ref. 12). High calc ium concentratio ns tend to decrease

12

boron toxicity (Ref. 37), and the amou nt of boron adsorbed on clays increases with increasing pH ( Ref. 38).

Plants appear to have a high buffer capacity aga in st fluoride, and even large concentrations of avai lable fluoride in the soi l will not alter its uptake ( Ref. 16).

MICRONUTRIENTS EFFLUENTS

AND

NON -ESSE NTIAL

ELEMENTS

IN

Most of the ions described above are present in effluents (Table

11). Their transference in aqueous systems has been evalu ated by Gibbs (Ref. 39), who determined the number of ions tra nspo rted by the fo ll owing systems: 1.

2.

3.

4.

5.

In solution and organic complexes.

Adsorbed on solids.

Precipitated and co-precipitated entities.

In organic solids.

In crystalline sediments.

No consistent pattern in the number of ions"transported by the different systems was observed, indicating that any effluent w ill have to be eva luated on its own mer its. It is likely, however, that sewage effluents co ntain a great proportion of its ions in organic complexes.

Although sewage effluents usually have a comparative ly low content of metal , their app licat ion may eventua ll y lead to dangerous levels in agricu ltural soi ls. Sewage farms ope rating for 70-100 years in Europe have experienced decreases in yields due to accumulation of copper and zinc (Ref. 40). Johnson et al. (Ref. 27) report that application of 1120 mm per year of raw sewage for a period of 48-73 years on pastures at Werribee, Melbourne, has resulted in increased nitrogen, organic carbon, and phosphorous in the soi l.

While the carbon/nitrogen ratio dec reased, the ca lcium/magnesium ratio increased , potassium remained constant, all trace elements increased, and exchangeab le nickel and zinc (0.1 N HCI extractant) increased considerably.

The zinc equivalent of toxicity (described earlier) in fact exceeded the danger value in top soils irrigated for 60 years or more.

Plant uptake largely reflected soil content. Eighty -ninety per cent of zinc, cadmium, chromium, and lead was removed by the soil plus pla nt, making this procedure at least as efficient as secon dary treatment works. Nitrogen and phosphorous were removed more efficiently than could be expected by conventional treatment (Ref. 27). Effluents from industries usually have too high a heavy metal content to be applied directly. Metal ions may be removed by chemical precipitation, electrode deposition, solvent extraction, reverse osmosis, or ion exchange, depending on the kind of ions and their concentration (Ref. 41).

SALINITY Wherever irrigation occurs, the danger of sali ni ty looms. Salinity refers to the total concentration of ions in the effluent, and is frequently measured by the Electric Condu ctivity (EC). Otherwise the weight of solute is determ ined, following evaporation of the solution; th is is expressed as Total Soluble Solids (TSS) . A convers ion factor is frequently applied when conve rting EC to TSS, although the regression may not be exactly linear.

The effects of salinity are an important factor in the water balance of crops and hence in their nu trition and product ion. Apart from the total effect of ions the effects of the individual ions must also be considered. Divalent ions (ca lcium and magnesium) are held more tight ly to colloid surfaces t han monovalent ones (sod ium), thereby reducing the zeta potential of colloids, al low ing coagu lation to occur.

Coagulation results in conglomeration of soil particles interspersed with air spaces in contrast to the dispersed colloids, which result when sodium dominates, and which leads to impermeable soil structure.

The Sodium Adsorpt ion Ratio (SAR), given by Na+/v(Ca2+ + Mg 2 +)/2 and the Exchangeable Sodium Percentage (ESP) of the soi l are two indicators of sodium hazards. The two parameters are often combined by regression equations, and conversion tables or nomograms. The USDA uses four classifications of water on the . basis of salinity, ranging from low to very high salinity, and four classifications on the basis of sod ium hazards ranging from low to very high (Ref. 42) . SAR val ues of 8- 12 and ESP va lues of 10- 15 per cent are frequently cons idered approach ing danger levels.

App lication of gypsum (CaSO 4 ) wi ll alleviate these, thus the SAR values were lowered 3-4 units on rice soils in the Kimberleys, when gypsum was app lied. Calci um displaced both magnesium and sodium from t he exc hange comp lexes Ref. 43).

Sodiu~ may cause tox ic ity to plants before danger levels for the soi l structure is 'reached. This may occur 'at ESP values as low as 5 per ce nt ( Ref. 4).

High bicarbonate concentrat ions wi ll precipitate calcium and magnesium as their ca rbonates, thereby increasing the SAR values.

The residual sodium carbonate (RSC) - the difference between the sum of bicarbonate io ns, and the sum of calcium and magnesium ions, - expressed the bicarbonate hazards. Bicarbonates may induce iron ch lorosis and cause reduction in growth of plants (Ref. 44 and 47). App li cation of gypsum will reduce the bicarbonate concentration, and application of 8000 kg gypsum ha· 1 on rice soils in the Kimberleys increased dry matter production of rice by 100 per ce nt ear ly _in the growth period. This ultimately was manifested in 20-30 per cent higher grain yields. These yields corre lated significa ntly w ith decreases in bicarbonate concentrations (Ref. 43).

Antagonism and synergism between ions exist. Thus antagonistic effects have been observed between phosphorous and zinc (Ref. 13 and 17), and between iron and zinc. Decreases in yields of maize were fou nd when the ratio of Fe/Zn in the plant tissue was below 1.5 or a P/Fe ratio 60 or a P/Zn ratio 300. Antagonism has also been found between Mn 2 + and Fe, and between P and Cu (Ref. 13 and 44) . Synergism has been observed between complexing agents and major nutrients such as nitrogen and phosphorus. (Ref. 48). Toxic effects of zin c and cadmi um or nicke l and cobalt as sulphates were found additive, whereas the combined toxicity of nickel and zinc, copper and zi nc, or copper and cadmium was much greater than additive (Ref. 16).

Soi l and plant type, the age of the plant, and the mode of efflue nt app lication greatly influence the effect of salinity. Waters of 6000 mg/I T SS and above have successfully been used on sandy so il s. Boyko (Ref. 45) has extensively investigated these conditions and made clear that water percolates rapidly through the soil profile in sa nd y soils, where the root system is well aerated. Magnesium and sod ium chloride, the components he considers most harmful to plants, are easi ly leached beyond the root zone, while upward movements may deposit magnesium and calcium salts as crustaceous material on the soil surface. Feeder roots of plants are only in co ntact with the salty water momentarily , and oxygen is well suppl ied. Boyko claims furthermore, t hat with lowered night temperature condensation forms on the root, providing them with pu re water, and that a ba lanced salt solution such as sea-water is less damaging to plants than a solution containing major amounts of a single component . · The sensitiv ity of plants to sa lin ity may vary ten-fold (Ref. 50), but depends also on the developmenta l stage of the individual plant (R ef. 4 ). The germination stage has been found to be the most se nsitive (R ef. 50). Soaking seeds prior to sowing in saline solutions has been reported to increase the salt to lerance of seedlings (Ref. 45) .

Trickle irrigation allows use of water of higher salinity than that of spr in k ler irrigat ion, as it adds the effluent in constant but smaller amounts, and the effl uent does not touch the crop foliage (Ref. 4, 45 and 46).

Drainage and leac hing are importa nt features of irrigation . Poor dra inage has destroyed much so il . In Iran about 25 million ha are salt affected. In west Pakistan about 40,000 ha'·· go out of production yearly. In India about 6 mil li on ha have gone comp lete ly out of product ion. This, in spite of the cla im made that irrigation technology is now so fa r advanced that irrigation agriculture can be permanent (Ref. 45). · The amoun t of ir rigat ion necessary to leach out the ions from the root-zone of plants is given by the formula for Leaching Requirements (L R) : EC L R= iw

~

whe re

EC · dw iw ·is t he sa lin ity of the irrigation water and ECdw is

salinity ot the drainage water. ECdw is usually selected as the electric conductivity of the saturation extract (EC ) at which the yield is reduced by 50 per cent in experiments of Jniform salinity profile throughout the root-zone. The formula is based on the assumption of uniform irrigation, abse nce of rai nfall , no removal of salts by the crop , and no precipitation of salts in the soi I. Other formula allowing for these factors have resulted in lower LR (Ref. 4).

Sewage effluents frequently contain fairly high concentratio ns of salts. The Glenelg treatment works in South Australia has managed to decrease the TSS from 2,500 mg/I in 1933 to a present level of 1,500 mg/ I (Ref. 3). Somewhat similar levels have been obtained at Werribee (Ref. 2).

PESTICIDES Pesticides are ubiquitously present in the env ironment, and they also find their way to effluents. Three groups may be considered: insecticides, fungicides, and herbicides. These belong to three chemical groups: 1) inorganic compounds (co~er sulphate, lead arsenate, mercuric chloride etc.) the effects of wh ich have been dealt with earlier, 2) organo-chlorines (DDT, Dieldrin , Aldrin etc.) the characteristics of which are chemical and biological stability, insolubility in water, lrnd a tendency to become co ncentrated in food chains, 3) organo-phosphates and carbamates (Parathion, Malathion etc.) which are more soluble in water, and easily hydrolyzed (Ref. 4, 51, 52 and 53). Table 111 ( Ref. 53) depicts the hazards, sources, and sinks of these groups of pesticides.

Several pesticides degrade readily in the agueous phase and may do so_ within a period of 2 weeks ( Ref. 54), and the most persistent substituted urea and carbamate pest icides were not found to exist beyond 4 weeks, although they may exist in excess of two years in the sediment (Ref. 52). Fenac, a trichlorophenyl acetic acid, was found to persist in the aqueous phase in a pond 202 days after application (Ref. 55). The dipyridinium herbicides (paraquat and diquat) may readily disappear from solution, but they can become adsorbed to sediments where they may be very persistent (Ref. 52).

The degradation of organo-chlorines may become accelerated under anaerobic conditions as observed with lindane in flooded rice soils (Ref. 56).

When the pesticides reach the soil, many, espec ial ly amongst the organo-chlorines, are adsorbed to the soil particles. The power of adsorbents are in the soil particles. The power of adsorbents are in the following order: organic matter high-charge clays low-charge cl ays. Total surface area, water content, temperature, and pH are also important soil factors. Relevant properties of the pesticides include chemical configuration , dissociation constant water so lubility, and molecular size (Ref. 51, and 52). ' Degradation occurs by hydrolysis, and by microbial and photochemical action. Hydrolysis may be accelerated by adsorption catalysis (Ref. 52). Thiocarbamate, phenylcarbamate, substitu ted urea herbicides, and commonly used chlorinated aliphatic and phenoxy alkanoic acids (2, 4 , 5- T and 2, 4 D) are microbially degraded over a short time. Benzoic and phenyl acetic acids are more persistent. Picloram and trifluralin are among the more persistent ones (Ref. 52).

The importance of photodecomposition of pest icides is uncertain, but common ly it includes de-ha logenation, sulphur oxidation, and isomerization (Ref. 51). It is noteworthy that photochemically degraded Dieldrin Isomer 111 is almost twice as toxic to flies and mosquitoes as the parent compound (Ref. 52).

DETERGENTS These consist of a variety of chemicals with li pophi lic and hydro-philic properties balanced in the molecule accord ing to the planned use of the detergent. Anionic-active, cationic-active , nonionic, and ampholytic detergents exist. The anionic and catio ni c detergents are incompatible and will precipitate out if added together. The nonionic detergent is compatib le with either and is unaffected by salts, acids, and alkal ies. The anionic detergents are ordinary soaps (sodium - and potassium salts of fatty acids), and many synthet ic ones containing sulpho nates. Many of the cationic detergents contain quartenary ammonium sa lts, whi le non-ion ic detergents usually are may up of poly-hydric alcohols,

13

polyoxethylene chains etc., providing reactive centres for amides, ester,- and other linkages , rendering lipo-philic and hyd ro-pilic properties to the molecule. In addition to the surface-active ingredients detergents contain salts such as sodium sulphates, sili cates , sodium perborate, and chlorinated tri-sodium phosphates (Ref. 57). T he addition of perborate may conceivably add to boron toxicity, but generally, the greatest derogate effect of detergents .in agricultural effluents is their lowering of surface tension of water, resulting in foaming.

TABLE I Biological Function of Metallic Ions.

(Frieden, E. (1972) The chemical elements of life Sci. American 227¡52-60)

.

Metal Iron Iron in heme

HEALTH HAZARDS Pathogenic bacteria and viruses are major health hazards in sewage efflue nts, but they can be fairly weil controlled by chlorination (Ref. 58), but if this precaution is not taken there is potential danger. Thus an out-break of cholera occurred in Jer usalem i n 1970, when 250 cases were traced to the irrigation of vegetable crops with sewage effluents (Ref. 59. Chemicals causing acute or chronic toxicity, carcinogenic, teratogenic, and mutagenic agents must also be considered. Many of these health hazards are often complicated by long dormancy of their effects (Ref. 58).

Copper

T yrosinase Plastocyanin Hemocyanin

Organic chemicals, petro-chemica ls A lkalis, chlorine, inorganic chem ica ls Fertilizers Petro leum refini ng Basic steel works, foundries Basic non-ferrous metal-works, foundr ies Motor vehi cles, aircraft-p lating, finishing Flat glass, ceme nt asbestos products etc.

Textile mill products Leather ta nni ng, f ini shi ng Steam generation power plants

14

Cr

Cu

. '

Zinc

Heavy metals in effluents from major industries (Dean, J. G. et al. ( 1972) - Env. Sci. & Techn . 6, 518-522 As Cd

Aldehyde oxidat io n Electron T ransfer Protection aga in st Hydrogen peroxide Oxygen tra nsport

Ceruloplasmin Cytochrome oxidase

Carbonic Anhydrase

F

Iron utilization Prin cipa l terminal oxid ase Elasticity of aortic wa ll s !..Skin pigmentation Ph otosynthes is Oxygen transport in invertebrates

Carboxy Peptidase Alcoho l Dehydroge nase

CO2 formatio n, regulation of ac idi ty Protein digestion Alcohol metabolism

Manganese

Arginase Pyruvate carboxy lase

Urea formatio n Pyr uvate metabolism

Coba lt

Ribonucleotide reductase Glutamate mutase

Ona biosynthes is Am in o acid metabo li sm

Molybdenum

Xanthine ox id ase Nitrate reductase

Purin e metabolism Nitrate utili zat io n

Calcium Magnesium

Li pases Hexok inase

Lipid digestion Phosp hate tr ansfer

TABLE II

Ag

Aldehyde ox id ase Cytochromes Cata lase

Lysine oxidase

Full utilirntion of water, in particular via recycling, poses great demands on the user, the engineer and the scientist, but it becomes increasingly important to meet these demands, particularly in Australia, one of the driest of all conti nent s. The study of many of the ulterior interactions of water and its solutes with the environment is still in its infancy, but results are fast forthcoming , and an important task for the future is to collate, co-ordinate, and project these results into a model which can be used to establish a mon itori ng program for environ mental effects with regard to plant production, soil stability, health hazards. and so on.

Al

Actio n Photosynthesis Aeorobic oxidat ion of carbohydrates

Haemoglob in

IN CONCLUSION

Pulp, paper m1fls,' paper board , building paper board mills

Enzyme Ferredoxin Succinate Dehydrogenase

Fe

Hg

Mn

Pb

Ni

Sb

C:,n

Zn

TABLE Ill Properties of major pesticides and persistence in aquatic systems (Bowmer K. H., & O'Loughlin E.M. (1974) Pesticides in Water Proc. A.W.W.A. Sixth Federal Convention. Melb. 1974)

Pesticide

Persistence/hazards

Organochlorines

DDT, BHC, Lindane, Aldrin. Dieldrin, Endr in

Years. Fish kills biological magnfn, long-term sublethal.

Endosulfan

Fish k ii Is

Organophosphorus

Hours-weeks Variabl e acute toxicities -fish kills

Insecticides acaricides, aphicides Diffuse : crop protection, tick and flystrike control

Chemical hydrolysis

lnsectides ) Crop Fungicide ) Protection

Chemical hydrolysis

Carbaryl, Aminocarb Zineb

Hours-weeks Variabl e acute toxicities - fish kills

Miscellaneous Acrolein, Aromatic solvents 2, 4 -D, Amitrole, 2,2-DPA Diuron, TCA Diquat Copper sulphate

Hours Fish kills Days-weeks crop damage Weeks-years crop damage Minutes no hazard Hours fish kills

Aquatic herbicides: Injected into water Foliage spray Foliage or soil applied Foliage spray Algaecide

Vol atilisatio n, (?) hydrolysis Microbial and chemical degradation Adsorption (colloids ) Precipitation. adsorption

Dioxathion, Diazinon zinphos, Malathion, Parathion , Mevinphos, Monocrotophos, TEPP Carbamates

Insecticides.

Point : sewage, industry Diffuse : crop protecti, termite, mosquito co ntrol

Sediment, general environment Endosulfan metabolised

Note: Plastic materia ls, synthetics, meat products, dairy products, fruits and vegetable grain milling, beet sugar, beverages, and livestock feedlot industries have no heavy metal discharges.

REFERENCES 1. Norman, N .E. (1974) - Reuse of water in the pulp and paper industry . Proc. of Australian Water & Wastewater Association Sixth Federal Convention, Melbourne, 1974.

2. Hammer, U .T. (1973) Sewage disposal. An ecological approach. Probe 28, 10-12.

3. Cooper, P.G., Goss L ., and Matheson, W.E . (1974) - South Australian experiences and studies in effluent reuse for 1mgation. Proc. of Austra li an Water & Wastewater Association Sixth Federal Convention Melbourne, 1974.

4. Hart, B.T. (1974) - A compilation of Australian Water Quality Criteria . Australian Water Resources Council Technical paper No. 7.

5 . McKee J. E., and Wo lf, H.W. (1963) - Water Quality Criteria .

Ca l ifornia State Wate r Resources Control Board Pub lication No. 3-A. 6. Baier, C.D., and Fryer, W.B . (1973) - Undesirable plant responses with sewage irrigation. Journ . of Irr. and Drainage Div . 99. 131-141.

7. Simpson , J.R. (1974) - Fates of nitrogen fertilizers-plant uptake, soil fixation and losses to the environment under different cropping systems. Proc. of Symposium : Fertilizers and the Environment. Sydney, 1974.

8. Wetselaar, R. (1974) - I ncreasing the efficiency of nitrogen fertilizer usage by minimizing losses to the Enviro nment.

Proc . of Symposium : Fertilizer and the Environment.

Sydney, 1974.

9. Jakobsen, P. (1974) - Natural and ferti lizer nitrogen in streams and lakes. Proc. of Symposium : Fertilizer and the Environment. Sydney , 1974.

10. Frieden, E. (1968) - T he biochemistry of copper. Sci. Am. 218 No. 5, 103-115, 11. Achorn, F.P., and Cox, T.R . (1971) - Production, marketing and use of solid, solution and suspension fertilizer in fertilizer technology and use. In "Fertilizer Technology and Use" . (Ed. A.A . Olson, T .J. Army, J.T . Hanway, and V.J. Kilmer).

Second Edition . Soil Sci. Soc. of Am. Madison, Wisconsin.

12. Steenbjerg, F. ( 1965) - Plante rnes Aernaer ing. DSR Forlag, Copenhagen 1965.

13. Leeper, G.W. (1972) - React io ns of heavy meta ls wit h soil s with special regard to their app l ication in sewage wastes . Report prepared for Department of the Army, Corps of Engineers, under contract No. DACW 73-73-C-0026.

14. Heydem ann, A. (1959) - Adsorption au~ sehr VerduntenKupferlosungen an veinen Ton mineralen . Geochm ica et Cosmochimica Acta 15, 305-329.

Steeman Nielsen, E., and Wi um Anderson, S. (1970) Copper ions as poison in the sea and freshwater. Marine Bio l.

6, 96-97.

16. Lisk, D.J. (1972) - Trace metals in soils, plants and anima ls.

Adv. in Agron . 24, 267-321.

17. Jakobsen, P., And Wi lliams, B.G. (1972) - The effects of h igh phospha te concentrations o n rice disorders in the Ord Riv er Val ley. Proc . Austra li an R ice Research Co nference, Leeto n, N.S.W. 1972.

18. Karlson, N. (1952) - Analytica l work on zinc in the vegetat ion of Middle Sweden . Acta Agric. Scan. 2, 173-182.

15.

Agronomic controls over the 19. Allaway, W.H. (1968) environmental cycling of trace elements. Adv. in Agron. 20, 235-274.

20. M itchell, R. L. (1965) - Trace elem ents in soi ls. In "Chemistry of the Soil". (Ed . F.E. Bear). Second Edition . Am . Chem.

Soc. New York, 1956.

21. Chumbley, C.G. ( 1971) - Permissable levels of toxic meta ls in sewage used on agricultural land. Agr. Dev. Adv . Service (Wo lverhampton) M inistry Agr. Fish and Food Ad visory paper.

22. Chaney, R.L. (1973) - Crop and food chain effects o f toxic elements in sludges and effluents. Proc. Jo in t Conf. Recyc l.

Munic . Sludges and Effluents on Land . Nat. Assoc. State Univ . Land Grant Colleges.

23. Underwood, E.J. (1971) Trace elements in Human and Anima l Nutrition . Academic Press, New York, 1971.

24. Reisenauer, H .M . Tabikh, A.A., and Stout, P.R. (1962 ) Mo lybdenum react ion with soi ls and the hydrous ox ides of iron, aluminium, and titaniu m . So il Sc i. Soc. A m er. Proc. 26 , 23-27.

15

.J

Continued from page 15

25. Stou t , P.R ., Meagher, W. R. Pearson G .A ., and Johnson, C.M .

(1~51) - Molybdenum nutrition of crop plants I. The influence of phosphate and sulphates on the adsorption of molybdenum from soils and solutiori culture . Plant and Soil 31 , 51 -87.

26 . Mortvedt, J.J., and Cunningham , H .G. (1973) - Production, marketing and use of other secondary and micro -nutrient fertilizers. In "Fertilizer Technology and Use" (Ed . A .A .

Olson, T.J. Army, J.T . Hanway, and V .J. Kilmer) . Soil Sci .

Soc. of Am . Madison, Wisconsin .

27. Johnson, R.D ., Jones, R. L., Hinsley, T .D., and David, D .J. (1974) - Selected chemical characteristics of soils forages, and drainage water from the sewage farm serving Melbourne, Australia. Report prepared for the U.S. Department of Army.

Corps of Engineers 1974. In print.

28. Williams, C.H ., and David, D.J . (1973) - The effect of superpjosphate on the cadmium content of soils and plants.

Aust. Jour . Soil Res. 11, 43-56.

29. Willi ams, C.H. (1974) - Trace elements in soils and plants.

Presidential add r ess, Aust. Soil Sci. Soc ., Canberra 1974.

30. Jensen , S. , and Jernelow, (1969) - Biological methylation of mercury in aquatic organisms. Natu re (London) 223 , 753-754.

31. Goldwater, L .J. ( 1971) - Mercury in the environment. Sci . Am .

224 No. 5, 15-21 .

32. Chisolm, J.J. (1971) - Lead poisoning. Sci. Am. 224 No. 2, 15-23 .

33 .. Trelease, S. F., and Trelease, H .M. (1938) - Selenium as a stimulating and possible essential elem ent for indicator plants. Am .J. of Bot. 25, 372.380.

34 . Levine, V .J. (1925) - The effect of selenium compounds upon growth and ge rmination of plants. Am. J. of Bot. 12, 82.80.

35. Grant, A .B. (1965) - Pasture top dressing with selenium . N.Z .J. Agr. Res. 8. 681 .690.

36. Jones, G.B., and Belling, G.B. (1967) - The movement of copper molybdenum , and selenium in soils as indicated by radio-active isotopes . Aust. J. Agr . Res . 18, 733 -740.

37. Reeve, E., and Shrive, J.W. (1944) - Potassium -boron and calcium-boron re lationship in plant nutrition . Soil Sci. 57, 1-14.

38. Hingston, F.J. (1964) - Reactions between boron and clays.

Aust . Journ . of Soil Res . 2, 83 -95.

39. Gibbs, R.J . (1973) - Mechanism of trace metal transport in rivers. Science 180, 71 -73.

40 . Carlson, C.W., and Menzies, J.D . (1971) - Utilization of urban wastes in crop production . Bioscience 561 -564.

41. Dean, J.G., Bosqui, F.L., and Lanouette, K.H . (1972) Removing heavy metals from waste water . Env . Sci. and Technol. 6, 518-522.

42. Richards, L.A. (1954) - Diagnosis and improvements of saline and alkali soils. U.S. Dep. of Agr. Handbook No. 60.

43. Jakobsen , P., and Williams, B.G. (1972) - The ameliorative effects of gypsum on Cununurra c lay, and its bearing on rice disorders. Proc. Australian Rice Research conference . Leeton, N.S.W., 1972.

44. Jakobsen, P. (1972) - Rice nutrition on Cununurra clay.

Kimber ley Research Station Annual Report 1971-1972.

45. Casey, H.E. (1972) - Salinity problems in arid lands irrigation.

A Literature Review and Selected Bibliography . U .S. Dept. of Interior, Washington D .C. ( 1972) 46. Boyko, H. (1967) - Salt water agriculture. Sci. Am. 216, 89 -96. No . 3.

47 . Watanabe , F.S., Lindsay, W.L., and Olson, C.R. (1965) Nutrient balance involving phosphorous, iron, and zinc. Soil Sci. , Proc. 29, 562-568 .

48. Jordan, A .A., and Bender, M .E. (1973) - Stimulation of phytoplankton growth by mixture of phosphate, nitrates and o rganic chelates . Water Research 7, 189-191 .

49. Bernstein , L . (1964) - Salt tolerance of plants. U.S. Department of Agriculture, Agricultural Research Service, Agricultural In formation Bulletin No. 283 50. Millington, A .J., Birwill, C.H., and Marsh, B. (1951) - Salt to lerance, germination and growth tests under controlled sa linity conditions. Journ . of Agr . Western Australia 28, 198-2 10.

51. Halling, S.C., Kearney , O .C., and Alexander, M . (1971) Behaviour of pesticides in soils. Adv . in Agron. 23, 147-241.

52. Pionke, H.B., and Chesters, G. (1973) - Pesticide-sediment water interaction . Journ. of Env. Qual. 2, 29-45.

53. Bowmer, K .H., and O'Loughlin, E.M. (1974) - Pesticides in water. Proc. of Australian Water and Wastewater Association Sixth Federal Convention, Melbourne, 1974.

16

54. Eichelberger, J.W., and Lichtenberg, J.J. (1971) - Persistence of pesticides in river water. Environ. Sci. Technol. 5, 541-544.

55. Grzenda, A .A., Nicholson, N.P., and Cox, W.S. (1966) Persistence of four herbicides in pondwater. J. Amer. Water Works Assoc . 58, 326-332 .

56. Yashida, T ., and Castro, T .F. (1970) - Degradation of gamma BHC in rice soils. Soil Sci. Soc. Amer. Proc. 34,440.442.

57. Duthie, J.R. (1972) - Detergent developments and their impact on water quality. In "Nutrients in Natural Waters" (Ed. H .E. Allen and J. R. Kramer). Wiley lnterscience, New York, London, Sydney, Toronto, 1972.

58. Sloan, W.N. (1974) - Public Health aspects of domestic reuse.

Proc. of Australian Wastewater Association Sixth Federal Convention, Melbourne, 1974.

59. Report of a W.H .O. meeting of experts (1973) - Re-use of effluents : Methods of waste (1973) water treatment and health safeguards

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,... â&#x20AC;˘

GOOGONG DAM *

By R. E. GoldJinch

SUMMARY Googong Dam will be constructed as part of a major augmentation to the Canberra-Oueanbeyan water supply system. The design was carried out by the Australian Department of Housing & Construction, Canberra Branch, for and on behalf of the National Development Commission.

The original selection of Canberra as the seat of Federal Government involved considerations of the water supply requirements of the Capital Territory and provision for it was made in the Seat of Government Act 1909-1955. Apart from the Cotter River Catchment and others which are wholly contained within the Australian Capital Territory, the Commonwealth was given the rights to the use and control of the waters of the Oueanbeyan and Molonglo Rivers and their tributaries.

INTRODUCTION The Googong Water Supp ly Project consists of the dam described in this article, a Pumping Station and Treatment Plant of 363 000 3 m /day maximum capacity, 26 km of welded steel pipeline and other associated works. The project will be constructed in two stages: the first stage consists of the dam in its entirety and the rema ining works to half capacity; the second stage of the project w i ll involve completion of the latter works to fu ll capacity.

The existing Cotter River water supply system cons ists of Corin, ' Bendora and Cotter Dams and associated works and is capable of supp lying water on an unrestricted basis to a population up to 225,000 persons. On current trends this popu lation wou ld be attained early in 1976.

The Googong Project together with the Cotter River system will be able to supp ly water on an unrestricted basis to a total popu lation of 450,000 persons. The capacity of the Googong reservoir includes provision for ripar ian rights, topp ing up of the recreationa l and ornamental Lake Burley Griffin in Canberra and minor irrigation between the dam and the lake.

Googo ng Dam is located on the Oueanbeyan River approximately 9 km upstream of Oueanbeyan. It is a 60.5 m high rockfill dam with an earth core im;ounding a reservoir 119 x 10 6 m 3 and has a catchment of 875 km .

Th e general arrangement of the dam is shown in Figure 1.

GEOLOGY The geology of the dam site was f irst investigated as early as 1929 and the adits and shafts used during the investigation are stil l visib le. Subsequent ly geological investigations of a pre li minary nature were carried out by the Bureau of Mineral Resources, first ly in 1955 to compare Googong and Bendora Dam sites, and aga in in 1962 to compare Googong and Corin Dam sites. Geo logica l investigations were recommenced in 1970 and , after a full engineer ing and economic assessment, it was concluded that Googong shou ld be the next dam site to be developed.

The loca l rock in the area of the dam is a near vertical sequence of metasediments and dacites of midd le Si lur ian age known as the Co l inton Volcanics. The dacite has been intruded by granite of Siluro-devonian age. The embankment is founded ma in ly on dac ite, although the downstream toe and the higher levels of the left abutment are on granite. Shearing and jointing in the foundation rock are pronounced but permeabilities are low.

No major fau lt zone has been found on the dam site . However fracture zones with associated deep weather ing exist, probab ly caused by the intrusive effect of the granite and associated hydrothermal activities.

Both granite and dacite are expected to be su itab le for rockfi ll , although the massive nature of the granite could present some fragmentation problems. *R. E. Goldfinch, Dept of Housing and Construction, Canberra Branch.

FIG 1 The reservoir area is considered to offer no leakage problems and no areas of slope instability have been detected. The reservoir is underlain by folded and sheared slates , sandstones and I imestones of the London Bridge formation, and slates and dacites of the Co linton Volcanics.

MATERIAL INVESTIGATIONS A_ satisfactory core material deposit, in excess of the quantity requ ired, has been found in a sma ll va lley approximate ly 1 km north-east of the dam site. The material consists of slope-wash generally classified as clayey sands (SC ) and silty sands (SM).

Laboratory resu!ts have indicated that the material has good grading, compaction and permeabi l ity properties at optium moistu re content or below. Above optimum moisture content, compaction problems could increase due to a loss of cohesio n, particu lar ly in t he silty sands.

It is considered that sufficient sand for fi lter requirements is availab le along the river upstream of the embankment.

CONSTRUCTION PROCEDURE Hydrological studies have ind icated that f lood probabilities are considerab ly reduced in the drier September to March period of the year. For this reason it is considered necessary to construct the bu lk of the embankment in this period.

BRISBANE POLLUTION CONTROL Hawker Siddeley Brush Pty Limited Environmental Division has secured a contract worth $1 .16m from the Brisbane City Council for the design, manufacture and commissioning of a trave lli ng sl udge lifter complete with gantry spanning four drying beds and associated conveyor equipment.

Due for comp letion in the latter half of 1976, this is to be part of a total waste water treatment scheme bei ng designed and constructed by Brisbane City Counci l.

Insta ll at ion of the sewage plant will be at Luggage Point, Brisbane, where it is to serve an initia l popu lat ion of 500,000.

In operation the equipment will be transferring wet sludge onto sand drying beds and, following drying, conveying the sludge to a stockpile prior to disposal. The equipment is also to be used for the preparation of the beds which are each 18 .25 m wide and 660 m (approxi mately½ mi le) long.

Design of the sludge lifter is being carried out by an associated company of Hawker Siddeley Brush, Templewood Hawkesley Activated Sludge Ltd, in the U.K. The sludge lifter and gantry structure wi ll be manufactured in aluminium by Highgate Engineering, a division of Comalco Ltd, in Brisbane . The associated co nveyor system is also being produced in Brisbane by Birkrad Engineer ing Services.

The entire plant w il l be manufactu red and insta lled utilis ing Austra lian materials and services.

Further information is avai lab le from Hawker Siddeley Brush Pty. Limited, 262 -284 Heidelberg Road, Fairfie ld, V ictoria, 3078 .

17

It is considered neith er practical nor necessary to construct a river diversi on system which would avoid the possibility of overtopping the uncompl eted embankment during construction.

Adequate reinforcement of the down-stream slope will be carr ied out to prevent surface unravell ing and, if necessary, deep seated slips.

Briefly it is proposed to make the following all owances for r iver diversion and embankment safety during diversion: a. Constru ct a 5 m di ameter diversion tunnel through the left abutment which, after plugging, would be utilized as part of the outlet works ; b. Reinforce the downstream rockfi ll slope w ith mesh and bars in such a mann er that at least 3 m of overtopping can be withstood ; reinforcem en t will probably be terminated 40 m above river level; c. Construct the lower 15 m embankment prior to the drier season, as failure of the dam up to this height would not have serious co n~quences; d. Constru ct the rema inder of the embankment in t he drier September to March season at a predetermined rate of progress which must be achieved by the Contractor; e. Constru ct the 3 m high spillway crest after the embankment is completed.

It is considered that if th e above provisions are adhered to, the r isk to both the embankment and downstream population is minimal and in accordance with the more conservative engineeri ng practices.

EMBANKMENT A typical cross sectio n of the emba nkment is shown in F igure 2.

The 60 15 m high embankment has a crest length of 336 m and contains a total of 758 000 m~ of material.

The embankment is situated in a short gorge section of the river and geological investigations have indicated that stripping and dental treatment on the foundations shou ld not be excessi ve. Adi ts and shafts fr o m 1929 investigations w ill be cleaned o ut , f ill ed with co ncrete and, if necessa ry grouted.

Cf:,

l"nFIH'flOUS f 1tl

{DF,tt.r @s,1, , t,droc1<t,ll

@

Rock fil l ,n 1 m \oyius

@ @

Rockf1llu,2mtoyers R1p-ro p

@

(;round surfoc, /

GOOGONG DAM - TYPICAL SECTION 10

0

I0Om

FIG. 2 SADDLE EMBANKMENT A secondary embankment will be constructed in a sadd le north-east of the main embankment. This sad dle embankment is 13.5 m high , 240 m long and has side slopes of 1 2.5. The cross sect ion is zoned into imperviou s materi al upstream and random f ill downstream, both of w hich will come from a borrow area immediately upst rea m of the sadd le. A bl anket filter 1 m thick will be provided at the downstream toe. The upstream slope will be protected with riprap and the downstream slope is to be grassed .

The foundations for thi s sad dle embankment although weathered are fai rl y impervious and, as o nly 6 m of water will be reta ined at fu l l supply level , grouting is co nsidered necessa ry.

18

SPILLWAY The spillway cons ists of a 124 m long, curved, free overflow crest and a 64 m long concrete li ned chute, converging to 62 mat the lip.

Flows down the spillway, after passing from the l ined ch ute into an unl ined rock channe l, wi ll cascade or d ro p into the lower (g ran ite ) quarry wh ich will act as an energy d iss ipating pool. It is anticipated that some eros ion will occur at higher spi llway discharges, and slides may develop in the rock cha nnel. It is expected that a stable slope will eventually be achieved between the lip of the lined spillway chute and the floor of the lowe r q uarry . A concrete and grouted cut-off will be provided at the l ip of the sp illway chute to prevent any fu rther headward erosion in the sp illway cha nnel.

The excavat ion for the spi ll way and spi llway approach channe l will in effect form the upper (dacite) quarry which, toget her with the lower (granite) quarry, will provide the rockfi ll material for the emba nkment.

The maximum probab le f lood infl ow of 4530 m 3 /sec was ca lculated using a maximised storm determined by the Bureau of Meteorology, together with a unit hydrograph derived from a flood at the dam site in 1925 which had a recurrenc interva l in t he order of 100 years.

OUTLET WORKS Both water supply and river discharge out let system s w ill be provided, and the two systems w ill be interconnected for added f lex ibility and for maintenance. Th e in take tower will co nsist of a circ ul ar dry-type reinforced concrete tower founded on rock and co nnected to pipework in the t unnel through a wet shaft. Water supply can be drawn from any of the six intake leve ls in the tower.

The intakes cons ist of 1100 mm diameter pipes and are provided with trash racks, stop logs, butterfly va lve closure, etc.

EMBANKMENT DETAILS Whil st wate r p ressure testing of t he diamond dr ill ho les has indicated that the foundations of the embankment are reasonably impermeable, both blanket and curtain grouting wi ll be ca rried out.

The grout curtain wi ll be cont inu ed beneath the spi llway crest.

A relative ly wide core (0.8 x height) was se lected due to possibl e non-un ifo rmity within the core borrow area. The co re has been in cl ined upstream to assist in obt aining acceptabl e slope stabi lities with the most economica l embankment sect ion. The co re depos it contains some areas of a coarser mater ial. For this reason, the provision in the downstream sect io n of the core of a zone with a slightly reduced grading req uirement is being c~ nsidered, to enba le this coarser material to be used rather than wasted.

Relatively narrow filters, 1.8 m upstream and 2.5 m downstream , w ill be prov ided each side of the imperm eab le core. A processed fi lter mater ial, probab ly from river sand, some river agg regat e and cru shed aggregate , wil l be used.

Adjacent to each filter selected rock fill zones will be constructed , probab ly consisting mainly of dacite whi ch, because of its close joint spacing, should provide a sma ll er sized rockfill. It is planned that all rockfill material for the embankment wi ll come from two q uarries which wi ll form the basis of the sp illway excavation.

A leakage co l lection system, fo und at ion p iezomet ers and monuments for deformation surveys wi ll be install ed to monitor the performance of the dam after construction.

A low level outlet through the tunne l plug will normally be used for river discharges; however it is also an integral part of the water supply system at times of low reservoir level. River releases wi ll be contro ll ed by free discharge valves of the Howell-Bunger type: a small 200 mm diameter va lve for the normal riparian discharges, and a 760 mm diameter valve for larger re leases.

A water supp ly drawoff of up to 363 000 m 3/ day has been planned. However addit io nal capacity is provided in t he towe r and tunnel pipework for unforeseen future requirements: Up to 2.8 m 3/ s can be re leased to the river without affecting the f low in the water supp ly pipework. River re leases can be doub led by diverting the water supply flow to the river discharge va lves, with a conseq uent reduct ion in the water supplied to the Pump Station .

CONTRACT ARRANGEMENTS A contract for construct ion of the Dam was awarded to Th iess Bros. P/L. for the sum of $9, 142,000 on 4th March, 1975.

The pumping station and water treatment plant will be described in the next issue of "Water".

THE DISPOSAL OF ALUM SLUDGE OR TOOTHPASTE

- JELLY -- CHOCOLATE - ROADMETAL

By G. C. COSSINS Water Supply & Sewerage Design Brisbane City Council The majority of the world's municipal water treatment plants use alum (aluminium sulphate) as a coagulant for turbid water. This is the least expensive coagulant used in present day rapid filter plants.

The aluminium hydroxide is precipitated as gelatinous floe in the water.

Various stirring devices are then used to encourage the floe particles to grow by accretion. In the process the colloids in the water have their charges neutralised and then the colloids are engulfed by the floe particles.

A quiet settling basin allows the majority of floe particles to settle to the bottom forming sludge whilst the settled water, still conta ining some alum floe, moves on to the filters; alum floe being essential for the operation of rapid filters. Sludge gradually clogs the filters and has to be removed from them periodically by backwashing.

Waterworks alum sludge is a most unattractive material. The community shows little enthusiasm for utilising it so, up until recent times, it was almost universally dumped back into the watercourse from which the raw water was drawn. Here it formed unsightly sludge banks which grew by accret ion until a fresh or a flood dispersed them downstream.

The game is now up! The dumping of alum sludge back into rivers is out and alternative ways must be utilised for its disposal.

THE PROBLEM Alum sludge dries very slowly. The gelatinous hydroxide floe that is so efficient in removing colloids is also very reluctant to part with its water. Higher proportions of alum are required in periods of low turbidity. The rate of production and disposal of alum sludge is therefore likely to vary throughout the year. This al l adds up to a difficult disposal problem.

More than 20 years ago the London Metropolitan Water Board carried out a thorough experimental investigation of rapid sand filtration in the hope that the hundredfold increase in filtration rates would reduce land use requirements significantly.

The Board reluctantly concluded that the problem of alum sludge disposal would outweigh the advantages of rapid filtration.

Fortunately for those now faced with a new and difficult problem, some waterworks have always faced it and their experimental and practical approaches to the problem have provided a great deal of data and understanding on which later generations are now able to draw.

Furthermore, as it is now evident that large amounts of money will be invested in sludge disposal in the affluent countries, the development of plant and machinery for alum sludge disposal has rapidly passed from

the hands of the amateur practitioners into the hard world of profitable exploitation.

The stakes are high and the product has improved immensely in a short time to the stage where data from an experimental case study will now furnish most of the constants required to develop a practical, economical and reliable alum sludge disposal system.

Various ways of dealing with alum sludge greatly affect its rate of drying and, therefore, the area of land required to deal with it. Lagooning results in the slowest drying rate of all. It requires a great amount of land for successful drying and the appearance of the lagoons is aesthetically objectionable. Very few plants have found lagooning to be economical.

The provision of under-drainc1ge in the drying beds developed conventional originally for sewage sludge greatly increases the rate of drying of raw alum sludge. The performance of the beds is greatly increased if the sludge is first thickened by simple Many types of mechanical means. economical sludge thickener have been on the market for a long time. The latest addition to this range is the tube clarifier which functions very successfully as a sludge thickener . Most of these devices will thicken alum sludge to a concentration of 3% of solids.

Alum sludge will flow and pump successfully up to a concentration of about 5% solids. At a concentration of 10% solid the alum sludge has the consistency of toothpaste, at 25% jelly, at 30% soft. chocolate and below 50% water it is hard and solid. When pre-thickened to 20% solids the drying process will continue relentlessly and the sludge will not re-absorb water.

SOLUTIONS Filter presses and vacuum filtration will further dewater the sludge and increase the drying rate of raw alum sludge but are rarely used these days with the raw sludge.

Likewise, a source of heat can be used to dry sludge rapidly to the solid stage but, with the increasing cost of fuel, this method is not receiving much attention.

Various techniques ca n be used to accelerate the al um sludge drying rate. The outstanding technique of recent years has been the introduction of conditioning agents to accelerate alum sludge drying. The inost successful of these conditioning agents are the organic polyelectrolytes. These persuade the aluminium hydroxide to release its water by disrupting the floe particles. Conditioned sludge dries rapidly on conventional sand-drying beds and can be lifted by mechanical sludge I ifters when the water content has dropped to about 65%. At this stage the sludge is quite firm and can be dumped into a quiet corner until it has become hard and can be used for dry filling.

If land is at a premium then various machines can be used to dewater the sludge and therefore subsequent accelerated

drying.

Centrifugal dryers were first introduced more than 70 years ago. A decade ago the improved types became popular in the U.S.A. whilst Europe preferred filter presses. Disillusionment over the reliability of the machines has caused the U.S.A. to swing .to filter presses whilst Europe has taken up the newer improved centrifuges with entb.usiasm. No doubt an equalibrium will finally be reached but the product is continually improving.

Sludge typical ly leaves a centrifuge with the consistency of stiff jelly and a solids content of 25%. It can be dumped in a quiet corner for further drying before dry land fill disposal.

When either a drier product is required or practice and prejudice dictate, a filter press can be used. Th is is a gigantic horizonta I press which squeezes the water out through prepared cloth at multiple points and gives a sludge product like chocolate with 30% solids content. This also is left to dry in the open awaiting dry land fill disposal .

At present filter presses and centrifuges offer similar economies and it is difficult to see which wil l gain the advantage. The filter press is a batch processor whereas the centrifuge has a continuous throughput. The filter press works best with conditioned sludge whereas the centrifuge can deal only with conditioned sludge, in fact, in the latest models, the conditioner is sprayed into the bowl with the entering sludge.

All the above methods deal with raw sludge modified only •by conditioning. The drying of the sludge can also be accelerated by reducing the aluminium hydroxide concentration. This is done by reacting the hydroxide with concentrated sulphuric acid and is similar to the reaction used in the production of alum from bauxite as follows : 2 A1(OH) 3 + 3 H 2 SO 4 - A1 2 (SO 4 l3 + 6H 2O · This process is used in a number of waterworks to recover alum for reuse as a raw water coagulant in order to minimise the cost of alum purchases: the saving being the differences in the costs of alum over concentrated sulphuric acid brought to the plant. The remaining sludge is highly acid and must be neutralised at some stage.

Sludge from the acid process neutralised with lime dries satisfactorily but it bulks enormously. The acid sludge can be dried satisfactorily and the underdraining can be neutralised.

TEST WORK With the introduction of the Clean Waters Act into Queensland legislation · it was clear that Brisbane City Council would have to find an alternative to river dumping for . the alum sludge from its Mt. Crosby plant and also to devise a satisfactory method of disposal for its North Pine River treatment plant which was then under construction. The problem was complicated at Mt. Crosby by the practice of intermittent cleaning of the sedimentation basins.

19

This practice had arisen in the days when the commercially available alum had a large insoluble silica content. Together wit h the acid conditions in the basins this was sheer hell on underwater bearings and made chain scrapers impracticable. Due to the construction of the basins this was the only type of scraper suitable in the circumstances.

Furthermore, the former days of cheap labour encouraged the practice.

Successful sludge drying is virt ual ly a continuous process so a large storage basin would have been required at Mt . Crosby to buffer the large discharges of sl udge from the · intermittent cleaning of the basins. A short study showed that it would be more economical to install sludge scrapers i n t he sedimentation basins tha n to build a sl udge storage reservoir at Mt. Crosby. Chain scrapers were instal led in No. 4 basin in 1974 and will be instal led in No. 3 basin in 1975 and No. 2 basin in 1976. The coff in shaped No. 1 basin, an adaption of a pure water storage reservoir, presents problems for the installation of scrapers. No satisfactory solution has been form ulated to date.

A pilot plant was built at Mt. Crosby in · 1974 to study both alum recovery and sludge drying with Mt. Crosby and North Pine sludges. It was located below No. 4 sedimentation basin at Mt. Crosby as a handy source of sludge and comprised a 68 kl steel sludge holding tank, equipped w ith perforated air pipes to keep the sludge stirred, a 20° conical bottomed fibreglass 7 kl tank for thickening primary sludge and a similar one for thickening secondary sludge, a 2 .25 kl fibreglass tank for alum solution storage, a 450 litre mild steel acid storage tank, a 100 I itre stainless steel reactor ta nk equipped with stirring paddles and a 450 litre mild steel tank for lime slurry storage.

The installation is completed by four drying beds each 3.3 m. square and consisting of 100 mm pea gravel underlain by 50 mm of 10 mm to 20 mm gauge ·crushing stone and underlain in turn to 150 mm of 75 gauge crushed stone, the whole being underframed by ag r icultura l pipes. The pipework is arranged so that raw sludge can be fed either directly on to the drying beds, or through the primary thickener and then to the drying beds or, alternatively, into the acid reaction tank.

From the acid reaction tank, the acid sl udge can be fed to the secondary thickener and thence to the sludge beds being neutra lised by lime on the way. Th e supernatant 'l iquor from the secondar y thickener is discharged into the liquid alum storage tank. North Pine sludge is brought across· in drums from time to time for testing.

Due to a series of those frustrating shortages which plague professiona l investigations increasingly in this age of aff lu ence, h·igh wages and overworked supervisory staff, it has not been possible to carry out all the investigations that were p lanned.

Nevertheless, useful results have been obtained to date and the pilot tests are continuing.

T he investigations to date have been concentrated in three fields: the chemi ca l characteristics of the sludge and treat men t by-products, the recovery of alum from sludge, and the drying characteristics of sludge on drying beds.

20

RESU LTS The buffering ca pac ity of both Mt .

Crosby and North Pine sludge has bee n measured and it was found that Mt . Crosby sludge required betwee n 30% and 50% more acid to obtain the. same p H and t he same aluminium content as the amo unt required by the North Pine sludge. The d ifference could be due to the different hardnesses of the two raw waters .

The concentration of catio ns prese nt in the solution recovered from the settling of the sludge after reaction w ith co nce n trated sulphuric acid was carefully measured , the reuse of the alum sol u tion in the treatment plant for flo cculation of the raw wate r could well result in the undesirable bui ld -up of metalions in the pure water from the plant. The analyses of the recovered alum solution are shown in Tab le 1.

It wil l be noted from the tab le t hat the co ncentrations of copper , nickel, chro m ium , iron and aluminium rise as the p H fa lls, whi lst that of manganese, zinc and ca lci u m fa ll. The tabl e, however , shows that t he onl y metals w hi ch are dissolved in sufficient quantities to require considerat ion are manganese, iro n, calci um and aluminium, taking in to account raw water dosage levels.

Aluminium is not considered a prob lem as it is the flocculating agent for the treatment of the water and is the meta Ii on so ught in the study. Ca lcium is not co nsidered d etri mental at this level si nce it is nor mally high in the water supply, appea ring as hardness in t he wate r.

I ron and manganese were t he onl y problem cations encountered due to their co lour ing properties. T he iron is considered as a co-precipitating agent w ith al u min iu m leavi ng only the manga nese in do ubt.

T AB L E 2 Comparison of Properties of Recovered and Prepared A lumm

Prepared alum Recovered alum

Colour 1000 220

Turbid ity p H 500 3.4 35 2.4

From tests using t he recovered alum and the regul ar prepared alum several facts are worthy of note:(a) The two alum sol u tions are quite compa rable in qual ity at t he 9. 1 ppmA I dose as far as remov ing co lour and t urbidity, tho ugh at t he lowe r dose rate of 4.7 ppm Al, the prepared al um sol ution was superior; (b) the floe formed by the prepared alum solution was aga i n superior in prod ucing a larger mo re stab le floe; (c ) pH adjustment w ith li me of the recovered alum is impractical due to the high dosage of lime req uired. Adj ustment w ith ca ustic soda may be feasible; (d) the co lour in t he water supp ly var ies from 0-15 units and the t urbid ity var ies from 1.0 - 10.0 units (7). T he major ity of th e supernatant liq uors after floccuation fall within th is range and hence are accepta ble; (e)

from th e concentration of manganese left in the supernatant liquor after floccuatio n , it appears that on ly manganese co uld be tro ublesome.

alum However , as the reco ve red sol ution is to be used in associat io n with the prepared al um sol ut io n, it could be expected t hat the d ii ut ion effect of the recovered alum so lu t ion w ill eli minate t his h igh concent ration of manganese. This wo uld th en eliminate the problem of co lou r in th e f i nal treated wate r.

The optim um p H range for th e extracti on of alum using sul ph uric acid was fo und to be 2.0 to 2 .5 It has also bee n possib le t o make a roug h Quan ti tat ive assessment of t he recovery of al um and th e possible eco no m ics of chem ica l co nsumpt ion. In t hi s period up to 25t h September 1974, a tota l of 48.0 k ilo li t res of raw sl udge was treat ed wit h an ave rage specific gravity of 1.006 fro m w hi ch 24.9 ki lo litres of alu m liq uor w ith a st re ngth of 18 10 mg/ 1 A l and 445 mg/ I of Fe. At the then ru li ng pri ce of alum , th e recovered alum was worth $44.88. A f u rther 2.7 k il o li tres of supern at ant liqu or w as recovered from the dryi ng bed s.

T he cost of chemicals to product thi s alum were: Su lphur ic acid $23 .21 Polyelect ro lyte (Calgon) 3 .18 $26.49 The recove red alum was worth abo ut twice t he cost of t he prod ucing chemi ca ls.

Th e recovered alum so lutio n was f ed intermitten tl y in to No. 4 basi n du ri ng th e test ru ns of the pi lot p lan t and ap pea red t o be comp lete ly satisfactory. It had been hoped to dose the recovered alum into basin No. 4 continuo usly. T his wo uld enab le some assessment to be made of any poss ib le bu ild -up of undes ira bl e cat io ns o r oth er substances. It has not bee n possib le to d ate to do t hi s b ut a length y tria l w il l be ca rried o ut as soo n as p ractica ble.

Act ual ly, it was orig inal ly proposed t o make t he pi lot p lant a com plete ly integrat ed water treat m ent plant with its own floccu lat io n and settl in g bas in . It is o nly in th is way t hat a coml!) lete ly Quanti t at ive assessment can be made of t he alum recovery and reuse process. T he present open-e nded system has inevitabl e lossess w hich cannot be acco un ted for.

Some useful measure ments have been made of slud ge dry ing ti m es for bot h raw sl udge directly from t he slud ge hoppers of No. 4 bas in and fo r t he sludge fro m t he secondary t hick ener afte r t he acid tr eat ment.

N o po lyelect ro ly te co nditi o ned sl ud ge has yet been subject t o dry ing tests.

T ests have shown th at th e sludge ca n be lifted whe n t he mo ist ure co ntent fa ll s below 66%. In t he case of t he raw sludge, th is conditi on is reached aft er 16 days on t he dryi ng beds. Some tests ha ve bee n mad e of the reabsorption of sl udges af ter 35 days o n t he drying beds. T he d r ied sludge w as soaked in water for one ho ur and the w at er uptake was measured ; t he res ul ts being as fo ll ows: W ater p e rcen t age af te r 3 5 d ay s Dr ied r aw sludge Dri ed ac id sludg e Dri ed n eu t ra li zed slud ge Co n c lu sio n

2 5.6 % 33.2% 57 .6% Uptak e of wa t er afte r soaking 15 % 38 % 19%

TABLE 1

Analyses of Recovered Alum Solution for Metals (a) Mt. Crosby Sludge * Solution

Straight Soln.pH6.5 pH 5 .5 5 .0 4 .5 4 .0 3.5 3.0 2 .5 2.0 1.5 1.0

*

*

*

*

*

*

*

*

Copper (Cu) mgms 1· 1

Nickel (N i ) mgms 1· 1

Manganese (Mn) mgms 1· 1

Zinc (Zn) mgms 1· 1

Chromium (Cr) mgms 1· 1

Iron (Fe)

Calcium (Ca)

Aluminium (Al)

Lead (Pb)

N il Nil Nil Ni l N il 0 .08 0.08 0 .84 0 .80 0 .84

Nil Ni l Nil Nil 0.10 0.10 0 .27 0 .27 0 .33 0.32 0.46

Nil 13.1 14 .3 14.1 16.6 16.7 7 .6 6.5 5 .9 6.2 6 .9

6 .90 13.3 15.1 14.7 17.9 16.5 7.1 5 .8 5.5 5 .7 6 .2

6 .7 Nil Nil 0.4 0 .5 0 .8 1.3 1.38 1.35 1 .41 1.46

N il 90.4 251 .5 211 .7

17.5 128 .0 128.8 139 .1 161 .5 201.6 163.4 92.6 90 .8 96.1 108 .9

127.2 Ni l Nil Nil 92 185 2660 3700 4230 4290 3930

Nil Nil Nil Nil Nil Ni l Nil N il Nil Nil Nil

434.4 478 .2 642 .5 688 .8 760 .1 808 .6 816 .7

(b) North Pine Sludge Solution Straight Soln.pH6.5 pH 5 .5 5.0 4 .5 4 .0 3.5 3.0 2 .5 2 .0 1.5 1.0

*

*

*

*

*

*

Copper (Cu) mgms · l

Nickel (Ni) mgms 1· 1

Manganese (Mn) mgms 1· 1

Zinc (Zn) mgms 1· 1

Chromium (Cr) mgms 1· 1

Iron (Fe)

Calcium (Ca)

Aluminium (A l)

Lead (Pb)

Nil N il Trace T r ace 0.15 0 .21 0.37 0.34 0.44 0 .35

Nil Nil Nil Nil 0 .10 0 .15 0 .20 0 .2 0.2 0 .33 0.47

Nil 17 .2 20.9 22.9 25 .0 15.0 12.5 11.8 12.4 12 .7 13.1

10.3 N il Nil 0.1 0 .1 0.2 0 .2 0 .2 0.3 0 .3 04

Nil Nil Ni l N il Nil 0 .84 1.06 1.40 1.42 1.12 1.43

Nil 62 130 177 303 381 391 549 676 723 740

34 30.6 31.7 36.6 42 .9 20 .2 19 .1 21.4 22 .7 22 .3 23.9

30.0 Nil Ni l Ni l 222 1790 2186 2570 2485 2498 2507

Nil Nil Nil Nil Nil Nil Nil Ni l Ni l Nil Nil

* Expressed as mgms per Iitre of recovered sludge.

Summary of Mt. Crosby investigation Sufficient investigation has been carried out, already, at Mt. Crosby to indicate that the recovery of alum from sludge is practicable and would pose no special technical problems. Likewise, the drying of sludge on conventional underdrained beds also appears to be practicable. However, much work remains to be done before the full parameters necessary for the design of a practicable and economical prototype can be finally determined.

A pilot centrifuge is to be installed at Mr. Crosby to providf! additional data and a pilot sludge press may possibly be installed.

The sludge disposal system of the North Pine Treatment plant was designed at the outset as an integral system to deal with both settling basin sludge and filter washings. The combined sludge is gathered in a small circular, basin and thickened in a tube clarifer before being dried on conventional beds. The supernatant liquor is held in a detention pond for seven days before being chlorinated and discharged to the North Pine River.

WATER Water is far from a simp le commodity, Water's a socio logical oddity, Water's a pasture for science to forage in.

Water's a mark of our dubious origin, Water's a link with distant futurity.

Water's a symbol of ritual purity, Water is po litics, water's religion, Water is just about anyone's pigeon.

Water is frightening, water's endearing.

Water is much more than mere engineering.

Water is tragical, water is comical, Water is far .from the pure economical.

So studies of water, though free from aridity, Are apt to produce a good deal of turbidity.

"Kenneth Boulding Aqua, Spring 1972."

NEW REPORTS CONFIRM REDUCED HEART DISEASE IN HARD WATER AREAS Whil e d isagree ing on t he specific ca use, researchers have co nf irmed ea rlier stud ies li nki ng hard wat er areas to lowered heart disease death rat es. Dr. Henry A. Schroeder of Dartmouth Medica l Schoo l and Luk e Kramer of Brattl eboro, Ver mo nt , recently repor ted on a sta tistical stud y t hey had co nducted in some 9 0 cities. T hey speculated that soft water was mo re corro sive and hence bro ught t r ace meta ls from pipe wa ll s in to so luti on w hich over many years ca used d amage to t he heart and circulato ry syst em. Draw ing a seemin gl y opposite co nclusi on, t hat trace met als in hard water reduce hea rt disease ri sks, Dr. H. Mitchel l Perry, pro fessor of medici ne at Wash ingt o n Uni versity, St . Lou is, Mo., indicated that physicians have compa red heart di sease mortal ity rates in bo th hard and soft water areas w ith 60 soci oeco nomic fact ors, including smokin g and air po llution , and have found th at hard wa ter appeared to be t he on ly co nsta nt fac t or fo und in low hea rt disease areas. In addition , a te n yea r evalu at ion in Engl and has repo rted th at in five hard wa t er areas studied , t here we re near half as many hear t disease re lat ed death s th an in si x other areas utilizi ng softened water .

21 _j

WATER MONITORING We have in Australia many inland cities and towns which draw their water from rivers and lakes which already carry a considerable quantity of pollution.

Such problems are of a quite frightening magnitude in Europe where a river can meander through industrial areas in many cities.

The river Rhine drains its water from six countries such that when it reaches Rotterdam it is heavily polluted.

Philips originated the development of automatic water monitoring stations to continuously monitor the larger waterways.

There are presently over 17 of these stations standing sentinal on Europe's waterways.

The basic automatic water monitoring station is capable of monitoring the basic of dissolved oxygen and parameters turbidity, and secondary parameters of pH, · pC I, conductivity, Redox potentia l (reduction and oxidation), and temperature.

The original concept was for a fu lly automatic station which could be left unattended for a month. Thus the electrodes have regular cleaning cycles by means of an ultrasonic transducer, and standard solutions for pH and pCI can be introduced to calibrate the electrodes.

The unattended feature is very attractive in these days of inflationary labour costs.

I

To pick upon the water sample the water is pumped into the station from a floating pump rather than a suction pump in the station .

This eliminates the priming and reduces the risk of the dissolved oxygen reading being affected.

The pump must be in the main stream, thus it is normal to locate the station on an outer bend.

Two types of floating pump are available, the first consists of a tubular guide in which fits the floating pump. This assembly requires to be supported in the water . The second alternative has the floating pump located in a boat with a rotating filter unit. This version is more appropriate for Australia with the wide water level variations that are available here.

Two valves control the sequence of supplying the measuring block with river water, calibration fluid (1) or calibration fluid (2).

The calibration cycle can be initiated every 12 or 24 hours and will take 45 minutes.

The followina calibrations are available :-

In addition to these, conductivity electrodes ¥JS / cm and a cover a range 0-2000 resistance thermometer for temperature (0-30°c or 0-60°C). A separate water distribution system allows water into a light scatter turbidity meter (Hach) (0-100 FTU).

The measured parameters will be displayed on pen recorders to give a continuous record of pol lution levels.

From th is basic concept several variations are available for example other ion selective electrodes can be introduced into the block (pF, pNH 4 , pCa or pCN).

Our experience is that interference from similar ions and fatty deposits on the membranes, reduce the effectiveness of many of these ion selectives except where accidental "overspill" in a waterway is possible.

These parameters are f requently traces for other problems, and it is necessary to take water samples to determine the exact cause of the problem .

Alarm contacts on the recorders can switch on Automatic Sample Collection equipment which moves an index head over a system of valves to fil I one of the number of sample bottles when initiated by an alarm situation.

An alarm situation may be a drop in dissolved oxygen or a rapid rise in turbidity.

An alternative to a chart recorder could be a micro computer which scans the outputs and derives half-hourly averages which are stored either on paper tape or onto a magnetic cassette tape .

This information is corrected by the calibration figures and converted into engineering units. Once a day 24 hour averages are printed out together with new ca libration va lues.

A further variation would be the use of telemetry modules for collation of the information to a central processor.

The central processor or the micro computer can generate calibration signals.

The recording of these essential parameters is a prerequisite to obtaining sufficient data for the control of the water.

Many water authorities are interested in a more mobile station, with perhaps hand calibration at more frequent intervals.

Such a station has been developed by Philips for this market.

It contains a flow through block to reduce cleaning of electrodes.

The standard unit will monitor up to 6 parameters: : 5-10 pH pH : 2-4 pCI pCI : -500mV to +500mV Redox : 0-2000 uS/cm Conductivity : 0-100% saturated Dissolved oxygen : 0-30°C (or 0 -60°C) temperature 21% o2

15, 20,parameter

range calibration solution ( 1)

ca l ibration solution (2)

15,20, parameter

range calibration solution (1) 5-10 pH 2-4 pCI -500mV to +500mV 0-100%

calibration solution (21 6 .88 pH 2.2 pCI -130mV air 21 % 0 2

pH pCI Redox dissolved oxygen

22

9 .22 pH 3.2 pCI -350mV

Calibration would be required every few days, depending on local conditions, and would involve the removal of the electrodes from the block for individual calibration.

The water pick -up and monitoring are separate from the main apparatus and are dependent upon local requirements.

OXYGEN & OXYGEN DEMAND The major aspects of water quality measurement involve the balance of oxygen and nitrogen compounds in the water.

Dissolved oxygen can be measured readily by the Philips Dissolved Oxygen Meter and will give an indication of the oxygen available, whilst the oxygen use is a function of biological oxidation due to organic materials present in the water.

Obviously for 'good' water the demand must be below the dissolved oxygen availability.

The origin al method of measuring this demand was the Biochemical Oxygen Demand (BOD 5 ) technique which involved the oxidation of organic matter by micro-organisms and took five days to achieve. To improve on this chemica l oxidation methods were used (Chemical Oxygen Demand) which gave results in two hours.

With the introduction of the Philips Total Oxygen Demand (TOD) Meter this process can be reduced to less than three minutes.

This instrument relies upon the ability of zirconium oxide tubes to allow migration of oxygen through its walls when a voltage is applied across them (Faraday's Law).6 Further the converse is also used that a voltage is generated depending on the amount of oxygen in the tube (Nerust's Law) .

To avoid a logarithmic relationship a balance system is employed.

A nitrogen carrier gas is dosed with a small quantity of oxygen by means of a set voltage applied to a zirconium oxide tube. A water sample is injected and the sample and carrier gas are passed through a catalytic combustion chamber operating at 200°C .

Moisture is removed from the resultant gas by a dryer and fed into a second zirconium ox ide cell in which the oxygen is monitored and used to generate a difference voltage which is re-applied to the zirconium oxide cell to cause oxygen migration into the sample to restore this difference voltage to a ba lance.

This signal can be integrated to give a reading which can be directly calibrated in TOD value, which makes the instrument rather unique.

Many people now talk of Total Organic Carbon (TOC) which can be derived by simply adding a Non-Dispersive Infrared monitor to the gaseous output stream.

The Hydrogen is oxidised to water which is absorbed in the dryer, sulphur to SO 2 and SO 3 whilst the carbon and organic compounds are oxidised to CO. Combined nitrogen is oxidised to NO 3 and NO 4 and causes predictable errors in measurement.

Since the equipment is similar to a natural process it is readily accepted and shows very good co-relation to COD values .

Comparison of measured TOD and COD with theoretical values FOR DIAGRAMS & TABLES TURN TO PAGE 28

AWWA NSW REGIONAL CONFERENCE · The following is taken from the speech by the Hon. Sir John Fuller, M.L.C., Minister for Planning and Environment and Leader of the Government in the Legislative Council, at the dinner of the N.S.W. Branch - Regional Conference - "Decentralisation and Water" - at Orange, 15th March, 1975.

Introductory remarks included thanks for the invitation and hospitality extended to the Minister and his wife, and a commendation on the selection of Orange for a conference venue, "a fine example of decentralised activity".

The talk cont inued with a brief history of environmental planning in the State and the development of the twin Commissions to meet "the twin requirements of pollution control and environmental management t hrough properly assessed land use planning.

To ensure a carefully co-ordinated approach to these requirements, two Commissions function under my Ministerial administration the State Pol lution Control Commission and the N.S.W. Planning and Environment Commission".

"We can't plan properly unless we know that it will be properly policed and we can't po li ce our environment properly if it is not p lanned correctly.

It will be seen, Mr Chairman, that each Commission will contribute to the protection of the environment - one working towards the objective by planning the future environment and the other by attending to and policing the environmental problems of the day.

And, in accordance with the Governpolicy of co-ordinating and ment's streaml ining the functions of Government, t he role of the State Pollution Control Commission has been greatly expanded and strengthened.

The Commission now administers the Clean Air Act and the Clean Waters Act and wi ll also administer the noise control legislation which should be before Par I iament within the next week.

In accordance with the same principle, a new department of water resources has been set up within the Department of Public Works.

The Department of Water Resources will contro l all activities associated with water conservation and the planning and management of our water resources w i 11 be centred under the control of one Minister.

Since the present Government came to office in 1965 ex tensive surveys have been carr ied out to establish a ba lanced and sou ndly based programme for conservation, development and use of water - not only surface water but our groundwater reserves.

The water resources of some 30 ind ivid ual valleys have been assessed in these surveys and it is felt the creation of this new depa rtment of water resources wil l provide an opportunity to rationalise all activities relating to water supply and the use of water.

The new department wi ll place a greater emphasis on our sparse water resources and see that they are properly managed in the best interests of water users.

I should make clear, Mr. Chairman, that this new department will not be concerned with operations in the Sydney and Newcastle regions. These areas will sti ll remain the responsibility of the Sydney Water Board and the Hunter District Water Board. In the country regions, however, all water resources will be developed and managed by one Minister.

So much for the conservation and rationalisation of water resources. The responsibility of maintaining those resources in a condition of quality - in an unpolluted condition - will again be the responsibility of one Minister - the Minister for Planning and Environment.

We need to know in environmental planning what is genu inely of cultural value - what scenic and aesthetic units of the environment are in need of protection what sources of air and water pollution need minimising - what we can sensibly afford to do so that the whole community, and not just a favoured section, benefits.

We have reached the stage where we need to be searching for new techniques looking at new concepts - evaluating and discarding what is no longer appropriate of past approaches to such things as water sewage and water reclamation and reuse.

This is where an association such as yours, Mr. Chairman, can play a most important role and contribute positive suggestions to Government in these times of profound change."

•

In the major c ities on the coast where a large proportion of the State's population is concentrated, drinking water of good quality is generally being supplied through the adoption of a policy of protected catchmen t s in whi ch polluting activities are prohibited .

In the coastal areas, pollution control efforts are being directed towards the· prevention of pollution of river, estuary and ocean waters so as to protect recreation activities, fishery production and aesthetic qualities.

The situation is different in these areas west of the Great Divide. In these areas rivers provide both water supply and drainage systems.

The sewage and drainage from one town can become the water supply of the next town downstream, so the clarification of water and the treatment of waste liquids assumes much greater importance particularly as population increases as a result of the Government's decentralisation initiatives.

Generally speaking the quality of water in any particular basin reflects the quality of life of the people who live in that basin - or the degree of care taken to protect the whole environment.

•

FOR SALE Unbound copies of Water Pollution Control 1906-1972 (missing: 1908, 1926, 1938-Pt 2, 1952, 1954-Pt 3, 1958-Pt 1, 1972-Pt 1). Very good condition. (Jnl. of Inst. of Water Pollution Control.)

Price: $5 per issue (163 issues).

Will sell as a set only.

Sewage Works Journal (now Water Pollution Control Federation Jnl.) 1935-1939, 1947-1949 (missing: 1939-No.

2).

•

Price: $2 per issue.

International Water Supply Assn - Proceedings of 5th Congress, 1961, 2 vols.

Price: $25.

Owner: Mrs. M. Thistiethwayte, 25 Glen Road, Roseville, N.S.W. 2069. Telephone: 46-4747.

FROM THE LITERATURE

So we come back again to environmenta l planning and all the disciplines involved in environmental planning.

The U .S.A. American Water Works Associat ion 'Journal ' February 1975 issue, contains a very fine series of articles on "Water-Quality Criteria - Industry's Stake in the Water Industry". Water quality requirements of various industries are detailed and reuse economics and practicalities highlighted.

As I see it, environmental planning can be simply stated as p lanning w ith nature for the benefit of people.

Water quant 1t1es deta il ed for: -

And only those in professions such as you draw your membership from can appreciate how much we are going to depend upon the interdisciplinary approach to achieve these objectives.

Interdisciplinary skills entering into environmental planning add up to a considerable number.

There are the earth sciences, the biological sciences and the combination of these making up ecological science.

Technology enters in the form of engineering, architecture and town p lanning disciplines - in all of which the emphasis is changing from a strict physical science basis to something more in tune with human scales and values.

and

qualities

are

Various industries Textiles Petro leum Chemical Manufacturing Dairy and Food and various services Boi ler Feed Coo ling (once-through) Cool ing ( make-up) Process from various sources Fresh Brackish

23

CONFERENCE CALENDAR AWWA WORLD STUDY TOUR There are st ill some vacancies for members and their wives who wish to join the AWWA World Study Tour.

An extensive itinerary, technically satisfying but with tourist interest has been arranged encompassing Hong Kong, Tokyo, San Francisco, Reno, Lake Tahoe, Miami, Washington , Boston, London, Paris, Stockholm, Rome, Tel Aviv, Johannesburg, Windhoek, Melbourne and Sydney.

The Tour departs 26th September, 1975 and returns 4th November, 1975.

The all inclusive cost wil I be about $3000.

Applications and enquiries should be addressed to: Mr R .F. Goldfinch Hon . Federal Secretary AWWS P.O . Box 359, Canberra - Telephone (062) 81-9358 or to the Travel Agent Mr R. Priestley Arts and Festival Tours P.O. Box 355, Geelong, Telephone (052) 43-5208.

P .S. The Commissioner for Taxation indicates that Tour expenses could be considered for Tax Deduction purposes.

THIRD

NATIONAL CHEMICAL ENGINEERING, CONFERENCE, MILDURA, VICTORIA AUGUST 20-23, 1975 TREATMENT, RECYCLE AND DISPOSAL OF WASTES Organised by the Victorian Group of the Institution of Chemical Engineers this conference is co-sponsored by The Institution of Chemical Engineers (Australian National Committee), The Institution of Engineers, Australia, the Royal Australian Chemical Institute and the Australasian Institute of Mining and Metallurgy.

Aim The conference will provide a forum for people concerned with treatment, recycle and disposal of wastes in Agricultural, Forest Products and Urban Fields, in Food and Manufacturing Industries and in Mining, Meta llurgical. Chemical and Petro leum Industries.

The first half of the conference program has been designed to cover a large number of topic areas with presentation of problems and their so lu tions. In this way, it is hoped that a li vely interchange of ideas will occur.

The second half involves one day of four parallel sessions devoted entirely to specifi c so lutions to problems and opportunities for recycle in the industries mentioned above.

Venue Mildura, Vic to ria .

Plenary sessions wil l be held at the Arts Centre whi le the four parallel sessions will use the Grand Hotel and the adjoining Riverland Moto r Inn . Although the warmest city in the State, Mildura has a disadvantage, vi z. accommodation and other facilities must limit the number of participants to 250. The indicated response already exceeds this number so act now!

Registrations will be accepted on a first come first served basis.

Registration Fees Participants $60 Accompanying persons and students $20 The fees include a -~opy of the proceedings, the conference and barbeque dinners, lunches on Thursday, Friday and Saturday, morning and afternoon teas and transport between venues. Mea ls on the Wednesday are not covered.

Accompanying persons a," Pntitled to al I meals and visits.

Registration forms, information on accommodation. and copies of the comp lete program are ava ilable from: Dr. D .V. Boger, Department of Chemical Engineering Monash University Clayton, Victoria, 3168 . Telephone : 541 -3427

24

A.W.W.A. VICTORIAN BRANCH SPRING CONFERENCE LORNE HOTEL 10th-12th OCTOBER, 1975 THEME - "URBAN DISCHARGE PROBLEMS" In October, when the sun is beginning to break through the winter clouds, the birds are starting to sing and Engineers, Chemists, Biologists, Scientists etc. are trying to break out the winter doldrums, the Victor ian Branch of the A.W .W.A . will be holding a "BREAK -OUT" weekend conve ntion at Lorne.

A carefully conducted SECRET "POLL" has verified that ALL Victorian members will be eager to attend this "BREAK-OUT" on the weekend of the 10th , 11th and 12th of October, 1975. It has also been established that the families of these members will be DESPERATE for a weekend at Lorne to enjoy its well known attractions (beaches, bush, birds, golf, pubs etc. etc.) and with this in mind the Lorne Hotel -Motel has been booked for the weekend . It is unfortunate that a number of our members wil I not be able to attend this function - probably because they did not reg ister soon enough! (Pity help them when their fami lies find out.)

SYMPOSIUM The New South Wales State Committe will present a one day Symposium in the State Office Block. Phillip Street, Sydney. on 3rd July, 1975 entitled: "BEACH EROSIONS AND ITS IMPLICATIONS FOR AUSTRALIA" SPEAKERS AND SUBJECTS "The Beach Erosion Hazard " Mr. D .N. Foster B.E., M .I.E . Aust.

Officer in Charge Water Research Laboratory.

Manly Role .

"Geomorphologica l Studies" - Events Since the Ice Age Dr. Bruce Thom Australian National University, Canberra.

"The Problems of Data Collection for Investigation in Remedial Works" Mr . W. Hulcombe B.Sc . (Eng.) M.I.E. Aust.

Depa rtment Public Works, N.S .W. "B each Erosion and Damage in N.S.W. - the Implications for Management" Mr . Brian Watt B.Sc. (Eng.) , Research Officer Soil Conservation Service, N.S.W. "The Crisis in Northern and Other Beaches in 1974" A Speaker from the µosford Shire Council

AUSTRALIAN WATER & WASTEWATER ASSOCIATION NEW SOUTH WALES BRANCH IN CO-OPERATION WITH

THE HAWKESBURY AGRICULTURAL COLLEGE SCHOOL OF FOOD SCIENCES RESIDENTIAL AUTUMN SCHOOL AT HAWKESBURY AGRICULTURAL COLLEGE RICHMOND, NEW SOUTH WALES 8th-12th SEPTEMBER, 197~

THE TREATMENT OF WASTES FROM THE PROCESSING AND MANUFACTURE OF FOOD AND AGRICULTURAL PRODUCTS

8TH INTERNATIONAL CONFERENCE OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH SYDNEY, AUSTRALIA 17-22 OCTOBER, 1976 SPONSORS Elec. Commission of NSW A.W.W .A .

Hematite Petroleum, Vic. Government of Aust.

Humes ltd., Vic. Government of N .S.W .

Electro lu x, Vic. Government of Sth . Aust.

Shell Oil (Aust.)

Sydney Water of Board Aust. Paper Mills Melb. Board of Works Brambles Industries E. & W.S. Adelaide Wallace & Tiernan Brisbane City Council I .C.I. (Aust.)

Newcastle Water Board Petroleum Information Bureau Broken Hill Water Board Qantas Perth Water Board T.A.A. S.E.C., Vic. SOCIAL PROGRAMME The socia l programme wil I include events catering both for delegates as well as for those who accompany them - the ladies will be especially provided for to make Conference week a memorable expe_rience.

STUDY TOURS A special selection of study tours or technical inspections will be made available to all delegates. Post Conferen ce Continuing Education Seminars are to be held in Melbourne.

SCIENTIFIC PROGRAMME 1. Chemical Uuality Standards and their D etermination .

2. Biological Monitoring Parameters and their Characteri zation.

3. Public Health Aspects, Virology, Disinfection.

4. Biocides, Pollutant Accumulation in Macro-organisms.

5. Fish Studies.

6. Stream Analysis - Modelling - River Management.

7 . Eutrophicat ion - Chemical and Biologica l Aspects .

8. Marine Ecology.

9. Estuarine Pollution - Surveys.

10. Pipeline Disposal to Sea. 11 . Pollution from Oil and Offshore Materials Resources Development .

12. Groundwater Quality Studies.

13. Sewerage overlows, Storm Water Storage and Treatment.

14. Sedimentation, Sludge Characteristics and Thickening.

15. Slud ge : Dewatering, Incineration, Land Disposal.

16. Anaerobic Processes, Digestion, Septic Tanks.

17. Practical Aspects of activated sludge process, Nitrification, Denitrification, simultaneous phosphorus removal.

18. Aeration Systems, Oxygen plants.

19. Trickling Filter, High rate p lastic media, rotary discs.

20. Advanced Wastewater treatment, Physicochemical Processes, case stud ies of operation.

2 1. Large Treatment Plants.

22. Small Treatment Plants, Rural problems, Land Treatment, Lagoons, Transient population communiti es.

23. Industria l Wastes - Farm, Agricu ltural, Food Process.

24 . Industrial Wa5tes - Petrochemical, Synthetic Organics, Paper pulp.

25. Industrial Wastes Inorganic Toxicants - Non B iodegradable.

26. Water Qua lity Network Control .

27 . Miscel laneous - Papers of Wide General interest not covered within above Specific Categories.

The Conference wil l arrange two streams of concurrent technical sessions on each of eight half days as well as a Reception at the Sydney Opera House, and Opening and Closing Ceremonies at the Wentworth Hotel . Simultaneous interpretation in English, German and French w ill be provided . Included are Technical Tours, Workshop Sessions and Panel Discussions with World Specialists.

Authors must submit papers by September 15, 1975 in accordance with the Rules for Submission of Papers.

CONFERENCE SECRETARIAT Enquiries concerning the 8th Conference may be addressed to : I .A.W.P.R. 8th International Conference G.P.O. Box 2609, Sydney. 2001. Austra lia Cab les to "Conventions", Sydney, telephone: (code 27-6940.

02)

SUBSCRIPTIONS AUSTRALIAN WATER & WASTEWATER ASSOCIATION JOURNAL I enclose herewith the sum of $ ....... (Australian) as prepayment for supply of the following issues of 'WATER' March o

June

o

Sept.

o

Dec. o 197-

Note:AII subscriptions conclude with the December issue, renewals are due by the end of February for a full year's subscription. Price, including surface mail to all countries, is $1.00 (Aust.) each issue, made payable to the A.W.W.A. - 'WATER'.

Name .... .... ... ....... ... ....... .. ..... ................................... .

Address ........... .... ......... ............... .. ....... , ................. .

Mail this form to: John Craig, 'Water', Box 100, Caulfield East, 3145, Victoria, Australia.

A.W.W.A. MEMBERSHIP Request for Application Form for Membership of the Association To the Hon. Secretary, Australian Water & Wastewater Assoc., Mr. R. F. Goldfinch . P.O. Box 359, Canberra City, A.C.T., 2601

1, .... ................................... ... .............. ..................... .

(Name)

of, ..... ............ ... ... .. ... ... ............................................ .

(Address}

do hereby request an application form for membership in your Association.

Membership is in four categories.

1. Member - qualifications suitable for membership in the Inst. of Engineers. or other suitable professional bodies.

2. Associate - experience in the W.& W.W. Industry, without formal qualifications.

3. Student .

4. Sustaining Member an organisation involved in the W.& W.W. Indu stry wishing to sustain the Association.

25

NEW PRODUCTS AND PROJECTS

using standard so lutions and th en t he am mon ia concentratio n in th e samp le can be read directly from the sea le of the instrument .

MINIMUM SAMPLE SIZE E.I.L. AMMONIA PROBE FOR INDUSTRIAL AND LABORATORY USE The E. I.L. Mod el 8002-2 Ammonia Probe, which can be used for both industrial - and laboratory -app li cations is now available from Kent Instr uments (Au stra lia) Pt y Ltd. The Model 8002-2 Ammonia Probe was developed by and is manufactured by Electronic Instruments Limited, the George Kent Group Company specialising in analytical instrumentation and sensors. The Ammonia Probe makes possible direct measurements of dissolved ammonia and ammonium ion (after con version to ammonia) in aqueo us sol utio ns , easily and quickly.

Applications of the Ammonia Probe includ e the measurement of total or free ammo ni a in natural water, boiler feed water, · biological fluids, so il s, ef fluents and sewage; the measurement of total organic nitrogen (after Kjeldahl digestion) and ammoniaca l nitrogen in sewage. Another app lication is the measurement of nitrate (after reduction to ammonia) in sea water.

The model 8002-2 Ammonia Probe can be used for measurements over the range 1M to 1o· 6 M ammonia ( 1700mg/1 to 0.017mg/1), however meaningf ul measure7 ments down to 10· M ca n be o bta ined with care. Reproduci b i li ty of measurement is -typ ica lly within +2% of the ammonia level 'in the sampl e.

REQUIRED EQUIPMENT For bo th laboratory and industrial use the Ammonia Probe is co nnected to a sensitive pH meter (300mV f.s.d. ma x imum). Other requ irements are standard solutions and possibly a pH buffer for treatment of samples w hen total ammonia or ammonium ion d eterminations are made.

RESPONSE TO IONS Since the gas permeable probe mem-. bran e is hydrophobic, ions cannot enter the probe and t herefore wil l have no direct effect. Howeve r. at any given ammo ni a co nce ntrati on the partial pressure depends o n the total concentration of dissolved species in solutions w hich shou ld th erefore be left constant.

PRECISION The Model 8002-2 measures low levels of ammonia but, as it is a logarithmic device, it cannot detect sma ll changes in ammonia level at high co ncentration. With frequent ca libratio n, measurement sho ul d be reproducib le to +2% of the sample ammonia level.

TEMPERATURE EFFECTS Since the probe potential is effected by changes in temperature. standardising solutions should be at the temperature of the sample. The pro be ~n be used at temperatures from 5 to 40 C provided that temperature equilibrium is obtained.

MEASUREMENTS The probe may be ca librated wit h standard solutions of known free ammonia co ntent. Probe potentials are recorded in two or mo re standards in succession and the ca libration graph p lotted, o n semi -logarithmetic paper. of potential ( I in ear scale) against concentration (l og scale ). The ammo nia co ncentrat ions of unknown so lutio ns are then d etermined by reference to the graph. Alternatively, a p H /p ion meter w ith a logarithmetic concentration scale (for exam p le the E. I. L. Model 7050 instrument) may be used for the ca librati on of the probe

Standard Ammo nia Probes can be used for th e determination of ammo nia in samp les as small as 2.5 ml. However, if fitted w it h the f low -thro ugh ca p determinations can be made in samp le vo lu mes as low as 1 ml.

ON-STREAM INDUSTRIAL APPLICATIONS In on-stream industrial applicat ions the Model 8002-2 Ammonia Probe is used in an E. I. L. automatic selective ion monitor . This unit provides a cont.i(luous o ut put signal proportional to the ammoni a content which could be fed to remote recording control or telementry equipment.

Automatic sample preparation is performed w ith in th e liquid handling unit of the se lective ion monitor. w here the sa mple temperature is co ntrol led and th e reagent, if necessary . add ed and m ixed with the sample .

Th e E. I .L . 8000 Seri es monitor also includes an automatic sta ndisation fac ility to elimin ate any flow drifts in the instrument. Automatic standardisation is car r ied out at regular interva ls and in addition the standardising sequence may also be initiated manually by a push button co ntrol .

For further informat ion p lease contact Mr D. J . Rickard Marketing Manager Kent Instruments (Aust ra li a) Pty . Ltd .

70 -78 Bo x Road (P.O. Box 333 ) Caringbah, N .S.W. 2229 Telephone: (02) 525-281 1 Or contact the Kent office in your state

RESPONSE TO AMMONIA Th e M odel 8002-2 Probe detects free ammo nia by measuring its effect on th e pH of an ammon ium chloride so lution separated from t he sample by gas -permeab le hydrophob ic membrane. Ammo nia passes t hro ugh the membrane until the partial pressure in the thin f ilm of internal filli ng solution between the probe membrane and t he pH electrode membrane is the same as t he partial pressure of the sa mpl e. The equilibrium co ncentratio n of ammonia in the fi lm gives a characteristic pH valu e w hi ch is measured by th e specially designed pH electrode. As both the indicati ng pH electrod e and the reference electrode are built into the Ammo nia Probe th e technique for ammonia determinati o n is as si mpl e as for pH measurement.

RESPONSE TO OTHER GASES The probe w i 11 be affected by other gases if they change the pH of the internal fi ll ing solution (i .e. gases having an acid ic or basi c nature - such as H 2 S or CO 2 gas whe n in aqueous solutions) . At high pH , when measuring total amonia or ammonium io n co ncen tratio ns, H 2 S and CO 2 do not interfere.

26

Illustration: 1. E.I.L. Model 8002-2 Ammonia Probe used with E.I.L. Model 7050 pH/pion meter in a laboratory application.

OIL POLLUTION CONTROL INITIAL DETECTION Now released in Australia, is the range of Durham Oil Detection Buoys and Alarm Systems marketed by Tecalemit (Australasia) Pty . Limited. T hese systems have applications in harbours and ports, drainage canals, etc., for fast detection of spi ll ed oi l.

The detector membrane is specificall y designed so that it is both hydrophobic and lipo-philic. This means that water is repelled from the membrane and oil passes through.

Once the oi l has passed through the mesh, it flows into a storage receptacle and is detected by means of a float activated switch.

The Alarm is transmitted by cab le to the monitor .

Th e Alarm threshold is about 8 mis of collected sample and is preset. When this quantity has been accumulated, the monitor registers an alarm. Power supply for the monitor is 110 . 220 v, 50- 60 Hz. Range of the radio transmitter is up to 25 miles.

RECOVERY CDA systems, are a recent Austra lian development by Tecalemit. Capillardiamin, CDA, is a modified urea-formaldehyde foam which can absorb 70 times its own we ight in hydrocarbons, and is completely hydro phobic, non-toxic and non-flammable. It can be incorporated in filters and strainers for removal of o il contamination in effluent streams. In the advent of an oil spil l, a quick drying form of CDA can be generated on site.

This ensures that the oi l rema ins floating, bound up in the foam where it can not po ll ute.

After an o il spi ll is contai ned using CDA, it may be col lected by skimming and straining using nets, or, vacuum pumps, etc. It can also be al lowed to wash ashore for later collect io n, because when in side the foam the oil can not stain beaches. Any absorbed oil may be rec laimed from the foam by pressure squeez ing, acid-washing or distillation.

CDA has now created so much interest, that it is currently being exported to various parts of the World.

UNIQUE PRESTRESSED CONCRETE PIPES Unique P.C. pipes made for first time Production of concrete pipes with cathodic protect ion has begun in a new factory at Townsvi l le, Queensland .

This protection technique, w id ely used for steel pipelines, is being used for prestressed co ncrete pipes in Austra lia for the first time .

T he 1220 mm diameter prestressed concrete pipes are being made by Rocla under a contract valued at $840 000 for Townsville City Cunci's Ross Ri ver dam water supply scheme.

Cathod ic protect ion ensures freedom from corrosion of the stressed wire spiral which is wound aro und each pipe core and is regarded as supplementary protection for the Town svi lle pipes. It has been adopted by Rocla for use in aggressive soi l fo ll owing the experi ence of the company's overseas licensees.

Nine kilometres of pipes, each 5 m long, are expected to be installed by the counci l under contract starting in April ( 1975).

Initially, the pipeline will operate as a gravity main, bl,lt the pipes have been designed for a maximum operating head of 65 metres under pumping, to boost water supply in future years .

WATER QUALITY MONITORING SYSTEMS A broad range of water quality monitoring analyzers and data acquisition recorders, developed and manufactured by Martek Instruments, U.S.A., is now offered to meet most fie ld and industrial applications. These portable instruments provide in situ measurements of temperature, conductivity, salinity, pH, se lect ive ions , dissolved oxygen, t urbidity , and depth in fresh or sea water bodies to depths of 300 meters. Each instrument provides a recorder output for on-site recording or te lemetry of data. A permanent record may be obtained by utilizing virt ually any potentiometric strip chart recorder or Martek 's magnetic tape cassette data logger and/or paper tape data printer which al lows further processing of data by an external device such as a computer or calculator. A portable winch with slip rings permits monitoring and recording of data during profiling appli cations.

A suitab le ana ly zer may be selected for a ·variety of appli cat ions including remote, unattended long term surveys at specific sites or in situ, vertical prof ii ing. The instruments may be used in boats, and are equally adaptab le to permanent inst allation at industrial faci lities, aboard sh ips and offshore platforms, where co ntinuous measurements at an operating site are required.

Supplied in Australia by SELBYS SC IENTI F IC LTD . Offices in all states .

DESIGN_INITATIVE CUTS CULVERT COST The potential for cost saving in construct ion work through manufacturer des ign ini t iative has been well illustrated in a culvert project at North Ryde, N.S.W. A fresh design approach offered to the contractor, Thiess Bros., by Humes Limitied increased the competitive advantage of precast cul vert constru ct ion over in-situ work.

Th e 428 m, three-ce ll culvert will channel the waters of Shrimpton's Creek ben eath an access road for a new shopping complex for Grace Bros.

Three standard, crown type pre-cast units could have been used across t he width of the cu lvert, but Humes Limited was able to red uce the unit req uirement to two by its development of the "slab link" technique.

In this method, the central cel l is created by closing th e space between two outside units with a pre-cast sla b. Slab, joint and crow n design ensure the tra nsfer of side loading pressures from one side to the other.

The pre-cast structure is supported by an in-situ slab foundation.

Design of the Shrimpton's Cree k culvert units had also to provide for five changes of direction and one change in grade without any in-situ infi ll sections. Each unit was 1.22 m long , with a span of 2590 mm and 2740 mm legs .

Construction work, car ried out under the supervision of Wa l lis and Moore, eng ineers and surveyors, was assisted by the reduction in excavation width made poss ible by the "slab link" technique.

REAGENT CAN CAUSE CANCER (From W.P.C.F. Deeds & Data, January, 1975.)

Ortho-tolidine, the reagent most w idely used in the measurement of chlorine residuals at water and wastewater p lants, was listed as a known ca rcinogen in t he Reg ulations pub· li shed in the Federal Register (May 3, 1973). ·Calgon Corp., suppli e of several chlorine test kits that use ortho-tolidine, recently decided that, in view of the stringent government safety requirements, Ca lgon person nel would no longer handle the chemical. Prod uction of test kits that use ortho-tolidine has been discontinued by the com pany . A methyl orange procedure has been offered as a substitute.

Water and wastewater personnel should be aware that, because of its cancer-ca using properties, ortho-tolidine may be a significa nt health hazard .

FROM THE MINUTES OF THE MAY 2nd FEDERAL COUNCIL MEETING. TREATMENT PLANT OPERATOR TRAINING Mr Rod Williams of the Dept. of Urban

& Regiona l Development has indicated that D.U. R.D . is interested in funding training programmes.

A document had been prepared by the N.S.W. Public Works Department seeking funds to finance training. The Chairman fe lt the only role of the Association is to catalyse the required activity.

A Committee wi ll be implemented and will advise the Minister on action to be taken . Mr Wil liams had ind icated to him tha it should be possible for the Association to become involved in the matter of certification if it so desired . He believed that the Committee would be established by October. If requ ired the Association could become signatory to the certificate.

NATIONAL WATER SCIENCE & ENGINEERING RESEARCH INSTITUTE. Mr Sanders advised that he understood that money is available from D.U.R .D. for suitable research projects. The Association will wr ite to the Dept. of Environment indicating that it is understood that the Dept. wou ld like to receive the views of the Association in relation to research matters and that the Association would be p leased to meet with appropriate officers of the Department to discuss the proposals for a Research Institute.

27

SPOTTED OVERSEAS The city of Stuttgart, West Germany, as we\ I as many neighbouring cities suffered long dry summers in 1947 and '49. Coupled with rising water demand in the post war clim at e, long estab li shed hygienically saf e wate r su pplies were becoming inadequate .

A group of city and state authorit ies combined to bring water from BodenseeLake Constance on t he Swiss border , first by gravity and later by pumped mains, 160 k m to Stuttgart, with d ist r ibution to many other cities o n the way.

Most water suppli es in Germany come from undergro und sou rces and are trea t ed by iro n oxidation and filtration, the use of surface water required a somew hat d ifferen t approach. La ke water quality is seasonal ly variable, algae is the main contaim inan t , providing both suspended so l ids and co lour.

T o m in imise the pi ck- up of algae, the water is drawn from about 60 m d ow n, sti ll there is contin ual small algae content and annually a seasonal increase. The lakeside pumping station, situated b elow lake water level, pu mps the lake water up to the treatment plant, over 300 m above the lake.

The two pump suction intakes are protected by sta t ionary scree n s and elect r ic fish b arri ers which are occass ionally serv iced by divers.

Treatment is bas ical ly Microstraining Ozo ni sing and Rapid Sand Fi lt rat ion A nnual averages for t he raw water quality are tem perature 4 .5°C ph 7 .8 T .D.S. 200 mg/I Carbonate hardness 120 mg/I (as Ca

FROM PAGE 22

Constant current source

Rubber . -septum N2 - -·----

-

Dosing electrode _..,...

_..,....

Inner electrodes /

Measuring electrode

Combustion oven

Schematic illustrating principle of operation of Tod Meter

TOD values for nitrogen-containing substances.

Range used

Substance

C0 3 )

T ota l h ardness 160 mg/I D issolved oxygen 10-11 mg/I Oxyge n demand 8-9 mg/I (KMn 0 4 ) Plant Capacity I nitially 2160 I/s (41 MGD) commissioned 1958 Increased in 1964 by increased pump in g, to 3000 I/s (57 MGD) Present 7 500 I/s (14 3 MGD) with the addition al pumping, treatment plant and pipeline comp leted in 1969.

Costs of tne sc heme To 1958, approximately $50m.

The 1969 exte nsions , approximate ly $66m.

The circular plant inlet struct ure ho uses 12 microstrainer uni ts an d 12 ozo ne gas gen erato rs. Filtration is by rapid gravity nozzleless sand fi lt ers. Final chl or inatio n treatm en t protects the water on its lo ng journey to the consumer distribution centres.

Th e microstrainers and o zon isation produce a water su itably d eco lor ised and fl occulated for sand filtr at ion w ithout th e add ition of flocc ul ants and the attendant increased solids - sl ud ge disposal require ments.

28

Measure TOD

Theory Measure/ for Theory N ... N 2 N --. N2

Theory Measure/ Theory for N --. NO N --. NO

EDTA

3 000

1 04u

1 070

0.975

1 180

0.88

TRIS

3 000

1 740

1 735

1.00

1 900

0.91

Glycine

1000

854

855

1.00

1 042

0.82

HMTA

1 000

582

585

1.00

695

0.84

Dimethy l formamide

10 000

3 470

3 510

0.99

3 923

0.89

Urea

10 000

4 020

3 996

1.01

6 660

0.60

EDTA TRIS HMTA

Ethylenediaminetetracetic acid disodium salt Tris(hydroxy)aminomethane Hexamethylenetetramine

Comparison of measured TOD and COD with theoretica l values Substance

Range Used

coo ·

TOD Meas.

% theor .

Meas.

Glucose

100

61

100

48

Glucose

3 000

2 405

99

2 350

% theor.

TOD/ COD Meas.

80

1.25

97 .5

1.02

Glucose

10 000

2 350

97 .5

2 350

97

1.00

Mannose

3 000

2 820

99

2 785

97 .5

0 .99

Fumaric acid

3 000

2 010

98

2 035

99

0 .99

Malic acid

3 000

2 060

100

2 061

100

1.00

3 055

10 000

3 380

107

Sodium citrate

100

89

99

Sodium citrate

10 000

8 950

100

Ethanol

Plant supplied by Bamag Verfahreustechnik for Bodensee-Wasserversorgung (BWV) at Lake Constance.

Platinum catalyst

Electronic measuring and feedback

'COO measured by standard dichromate method .

85.5

92 .5

1.15

95

1.04

not measured

EFFLUENT SLUDGE DEWATERING • MUNICIPAL SEWAGE • WATER TREATMENT • OILY WASTES • NEUTRALISED PICKLE LIQUOR • METAL HYDROXIDES • ACTIVATED SLUDGE • FOOD PLANT WASTES • MISCELLANEOUS GUNK

DON'T use up expensive real estate to make a smelly lagoon or pay to have it dumped in someone else's backyard .

Let us settle your effluent problem with a centrifuge.

Capacities from 1,000 gallons per week to 10,000 gal Ions per hour.

Please telephone or write to arrange for us to test your sludge with one of three portable centrifuges we have built specifically for field testing throughout Australia.

SHARPLES - STOKES Pty. Ltd P.O. Box 731, Crows Nest, N.S.W. 2065. Cables PENNWALT SYDNEY Telephone (02) 439-4458 or (02) 439-3545 29

Oil Pollution DETECTION

COLLECTION

The Durham range of oil pollution detection buoys and alarms is now available in Australia through Tecalemit. Models available with radio monitors covering a range of up to 25 miles.

C.D.A.*, the Australian designed oil adsorbent has been proved in this country and is now expected overseas. 1 kilo of C.D.A. will adsorb 70 kilos of oil. C.D.A. foam may be generated on site.

â&#x20AC;˘ A registered trademark of U.F.C. Pollution Control P/L used under licence by Tecalemit (A 'sia) Pty Ltd.

TECALEMIT (A/asia) Pty. Ltd.

Please send me fu rther detai Is about C.D .A. and/or Durham .

Name:

Head office and factory Sheffield St, Woodvill e North , S.A., 5012.

. ............... . . .. ....... . .. .

Address: . . . . ...... ... .. .. . . ... . . . .. .. .

Bra nches: Sydn ey , Melbourne, Brisbane.

. ........... . . . ...... Postcode:

------------------------------ -- -------------------J

EFFUJErlT problems? liEITT.....,._. gets it under Eantral

Kent Instruments (Australia) Pty. Limited

4r

Sydney (02 I 525 2811 Melbourne (03) 874 1233 Adelaide (08) 352 1455 Brisbane (072 I 78 5761 Perth (092) 65 5377 Kent Instruments ( NZ) Ltd .

Auckla nd ( NZ) 59 7011 Wellington (NZ) 4 3173 Christchurch ( NZ) 6 4743

The George Kent Group

30

Save time, trouble and money with go -anywhere E. I .L. * pH / red ox control systems. If effluent is your problem you could need ...

Model 6320 pH / redox indicator controllerweatherproof, corrosion resistant Model 2867 electrode system-simple, ruggedconnects directly to controller Model 1630 slurry valve- unblockable, reliablefor low cost acid neutralisation The cost of the system? .. . Less than $600- and of course, ex -stock ... why consider others!

And we haven't mentioned KENT pollution control know-how and nationwide after-sales service *

11 GEOROE KENT Oroup Comp1r1v

PJ6360

Pollution .is a dirty word

Nobody likes to talk about sewerage: Humes helps clear up the matter.

V\1P hC'cH < 1 Int morC' ,1hou1 pollu11nn th,m

we do about man 's ,1hility 10 cope w 11h 11. good l'xample i,;; Melbourne·~ SouthE,v;;;rcrn Purifi cc1 tion Plant , ior which Hume~ 1,;; supplying co ncrete and plasti c pipe~ .1nd over UX)O conc rel e , tructura l unit~ to 1\

thC' value of some 52 million . Authonst•d

by the fores ighted Melbourne .incl Metro· politan Bo,ud oi Work!'-, th e plant , ont' ol l~e most modern m rhe world , will produu~ co lourles~. udou rl cs!t, recond1tioned \Wttcr for cli sc hargl' into B,v.. ~ Strait. A pre tt y clean solution to ,1 pollut1on probl em .

Humes also ,l1pplil'd " Pl,1-.filinf'" ,c-wr r ,1

pipes lo hring the sewage to the plant .111d " Plastiline" ~heet to protec t the uprcr

,t•ction, ni th e concre te gallC' n es whic h tr,111'-port scw,1gc around the plant. We have been hPlp ing to so lve problems like this for

,·c.ir ... Tak C' that Hume~ " Pla,tiline" ptpC' lor in'i lJncc: it 1, lined with PVC ,heel lo m,1ke !ht• roncrC' IC" free• irom H.S attack . Hume, 111\'<'nlf'd 11. And palcnl f'CI 11 - ,1, 11 did 1hc nwt hod ni CC'n triiug,1ll y , p1n n111g rc-i nlorcccl connell' p ipf' ,n tlw iir,1 plan·. Th.11 ,\ u,1r,11i,111 -born nwlhocl i, now u,cd Jround the world .

\VhC'thor ,t he on hug<' induo;lri al pro 1ects a!'! yo u o;ee here. o r p ipe and C'q uipm enl to brin g wate r to a sunbu rn t co untry or C'vcn troughs 10 wa1e r and feed the , toc k on whic h so much of our economy clC'pC'ncl s, Hum es

ha o; the w,1y. That ', Au'1r,11i,1n .

CONCRETE O PLASTICSO STEEL IH 5 \Vdh,1m Strc1•1. Mt'lhouuw , moo. rc•l<'ph,inC' ,)011221 .

• ,, •!

., ,

. .. ~ I ,. .,

31

(OJ))INDUSTRIAL ENGINEERING LIMITED restore the ENVIRONMENT .. !

CLEAN AND CLEAR WATERWAYS

withfflud Cat UNDERWATER WASTE REMOVER

MUD CAT dredges have been specifically designed for the economical removal of pollutant substances from waste settling ponds, weed-infested lakes and streams and for channel clean -out. Their unique features permit the removal of deleterious matter, weeds, silt, sand, sludge and industrial wastes with the minimum of water turbidity, thus allowing the pond, lake, stream or channel Deve loped by the Nationa l Car Rental System Inc., of U.S.A. AUSTRALIA WIDE DISTRIBUTORS:

to operate or flow normally during the clean-up operation. Two machines are available, the MC10 which will operate to a depth of 10'6" and the larger MC15 wh ich operates to a depth of 15'0". Both machines are prope lled in both the forward and reverse directions by winching along a wire rope which is furnished in the form of a harnessing kit.

t1ffl'l

INDUSTRIAL ENGINEERING LIMITED \\YI/

:~~;1:~~~iTP~e:;,~~~;i,c~:~ex

AA30756

Sales and Service through the I.E.L.-CONTRACTING PLANT ORGANISATION CONTRACTING PLANT (QLD.l DIV. CONTRACTING PLANT (N.S.W.l DIV. CONTRACTING PLANT (VIC.) DIV. SOUTH AUSTRALIAN DIV. INDUSTRIAL AVENUE WACOL 288 PARRAMATTA RD . AUBURN (TASMANIA} 585 GRAND JUNCTION RD .

' 32

PHONE 72 2122

PHONE 648 0301

cnr. FOOTSCRAY RD . & DUDLE Y ST.,

WEST MELBOURNE . PHONE 328 4571

WEST AUSTRALIAN DIV.

cnr. RUSSELL & SPARKS RDS .

GE PPS CROSS. PHONE 62 661 2 STH.COOGEE. PHON E 90 142 MCI

If clean water is an essential part of your process plant ... or the econom ic separation of suspended, entrained or dissolved materials such as chemicals, minerals, oils, spirits, etc .... then you need the specialised skills and equipment available from Permutit.

De-ionisers/ Filters Reverse osmosis u, u, Q)

0

~

C. Q)

Ul

Q)

0

e! 'iii

i;'i~

a:

0

Nobody treats water more cleanly than Permutit!

IPERMUTITI The Permutit Company of Australia Pty. Ltd. A subsidiary of The Permutit Company Ltd. , England.

A member of The Portals Group.

Cnr. Wattle Road and Short Street, Brookvale, N.S.W. 2100.

Telephone : 93-0311. Telex: AA24742. Cables : Thepermutit, Sydney.

P.O. Box 117, Brookvale, N.S.W., Austra lia 2100.

2-6 Hardner Road, Mount Waverley, Victoria 3149.

Telephone : 544-2811. Telex : AA31868.

P.O. Box 237, Mount Waverley, Victoria, Australia 3149.

Pennutit treats

pettigrevv water A COMPLETE SERWCE

IN

e e e

POLWTIONCONTROL

SURVEYS AND CONSULTING

e OVER 40 YEARS' EXPERIENCE AND

PILOT STUDIES OF WASTEWATER

e INSTALLATION, TESTING AND

DESIGN AND MANUFACTURE

RELIABILITY COMMISSIONING e CONTINUOUS AFTER-SALES SERVICE

HYDRAULICS ENGINEERING FOR INDUSTRY Pettigrew Engineering manufacture and installation i llustrated by Hydraulics for boiler water treatment for steam and fluids transfer; accompanied in this instance by air pollution control per medium of a 60 metre chimney stack . Th~ location is a large provincial hospital.

PETTIGREW ENGINEERING CO PTY l TD 34 REGINALD STREET, ROCKLEA, OLD., 4106, AUSTRALIA TELEPHONE (072) 46 3322 - CABL ES "PECOTRADE"

-