SAICE Civil Engineering 14(8), 2006

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MAGAZIN

EPU

BLISHERS

ASSOCIATI

ON

OF

SA

ENVIRONMENTAL

Civil Engineering| August 2006 1

OPINIONWhat distinguishes a profession? 3

LEGAL AND MANAGEMENTLiability of professional civil engineers 2 24

Update on broad-based black economic empowerment 26

AWARDSWinners of the National Innovation

Competition 2005 announced 27

CMA Awards set high standards for

precast concrete industry 29

IN BRIEF 31Isotherm goes green! ACSA kick-starts construction

of new central terminal building e-go Solutions expands

Africa operations to include satellite broadband solutions

Sinkhole adds to traffic blues PHD joins Golder

Chryso admixtures for multi-billion dollar Qatar airport

Clay Brick Association predicts boom in building industry

will continue Product design awards Update on

SAPPMA Developments in Port Elizabeth Potain tower

crane eases constraints on tight site Bigen Africa to

relocate to SAs first science park Creative concrete in

transport New ownership initiative structured from solid

foundations Upgrading of the Pretoria State Theatre

HISTORY AND HERITAGEPast Masters 3 and 4: Charles Jasper

Selwyn and John Montagu 40

SAICE AND PROFESSIONAL NEWSBuilding and breaking bridges at Maropeng 43

New standard for the design and construction of

reinforced soils and fills now available 45

Gijima 46

Profile: Its all about wanting to

see whats out there 4

The City of Cape Town brings treated

effluent to the forefront 10Remediation of water ingress to old gold

workings linked to active mines 12

UV-cured lining work offers solution to

pipeline renovation at Farnham Station 16

Focusing on the preservation

of the environment 20

Integrated water resources management

involving wetlands as wastewater

treatment alternatives on mines 23

PUBLISHED BY SAICE/SAISI

Block 19, Thornhill Ofce Park,Bekker Street, Vorna Valley, MidrandPrivate Bag X200, Halfway House, 1685Tel 011-805-5947/48, Fax 011-805-5971http://www.civils.org.za

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EDITOR

Sarie [email protected]

Tel 012-804-2754, Cell 082-376-2652

EDITORIAL PANEL

Elsab Kearsley (chair), Irvin Luker (vice-chair), SamAmod (president), Wally Burdzik, Johan de Koker,Huibrecht Kop, Jeffrey Mahachi, Jones Moloisane, EbenRust, Marco van Dijk, Michelle Theron, Sarie Moolman(editor), Barbara Spence (advertising), Verelene de Koker

(secretariat), Dawie Botha (executive director)[email protected]

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SA R525,00 (VAT included), International $110,00

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Tel 011-463-7940, Fax 011-463-7939Cell 082-881-3454

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PRINTING

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The South African Institution of Civil Engineeringaccepts no responsibility for any statements made oropinions expressed in this publication. Consequentlynobody connected with the publication of the magazine,in particular the proprietors, the publishers and theeditors, will be liable for any loss or damage sustainedby any reader as a result of his or her action upon anystatement or opinion published in this magazine.

ISSN 1021-2000

August 2006 Vol 14 No 8

ON THE COVERPaste technology is now well acceptedas both a reliable and cost-effective

backfill method and an attractive tailingsmanagement option for surface disposal.In this article Jaco Snyman and MichelleTheron give an overview of the latest trends(see page 8)

The latest trends in paste technology 8

Civil Engineering August 2006 Vol 14 No 8


3/432 Civil Engineering| August 2006

Date and venue Event and CPD validation number Presenters Contact details25 August Nelspruit

29 August Pietermaritzburg

30 August Richards Bay

31 August Durban

5 September Port Elizabeth

6 September East London

12 September Cape Town

13 September George

19 September Pretoria

21 September Upington

3 October Johannesburg

Water Law of South Africa A prac-

tical approach to resource manage-

ment and the provision of water

services

SAICEwat06/00073/09

Hubert Thompson Sharon Mugeri

[email protected]

25 August Cape Town 2006 Brunel Lecture (ICE London)

Engineering Civilisation from the

Shadows (focusing on the roleof engineering in addressing the

challenges with respect to the

Millennium Development Goals)

SAICEenv06/00067/07

Professor Paul Jowitt, vice-president

ICE

Dawn Hermanus

[email protected]

29 & 30 August SAICE House Technical Report Writ ing

SAICEbus06/00014/08

Mike Baillie Dawn Hermanus

[email protected]

28 August 1 September

University of the Witwatersrand

Design of Masonry Structures Professor Herbert Uzoegbo uzoegbo @civil.wits.ac.za

4 & 8 September University of

Johannesburg

The Application of Finite Element

Methods in Practice

SAICEstr06/00018/08

Roland Prukl Dawn Hermanus

[email protected]

4 & 5 September Durban

7 & 8 September Gauteng

11-12 September Cape Town

Best Practice in Specifying and

Inspection of Structural Steelwork

SAISC Presenters Elaine Taylor

[email protected]

6 September SAICE House Lecture: St rategic Public Transport

Network Project for the City of

Johannesburg

SAICEtr06/00082/07

Zwelakhe Mayaba

Kollan Pillay

Sharon Mugeri

[email protected]

7 & 8 September SAICE House Handling Projects in a Consulting

Engineers Practice

SAICEproj06/00003/08

Wolf Weidemann Dawn Hermanus

[email protected]

11 & 12 September Gauteng The Second Underground Operators

Conference

SA Institute of Mining and

Metallurgy

Lara

[email protected]

12 & 13 September SAICE House Business Finances for Built

Environment Professionals

SAICEfin06/00004/08

Wolf Weidemann Dawn Hermanus

[email protected]

17 & 18 September 2007 - China 5th International Conference

on Current and Future trends in

Bridge Design, Construction and

Maintenance

ICE Dayle Long

[email protected]

For more informationon courses, venues and course outlines please visit www.civils.org.za/courses.html

ISSUE OF MAGAZINE DIVISION/FOCUS BRANCH(ES) D-DATE

October Urban and Rural Western Cape (Contact Tony

Murray) and Southern Cape

1 September

November/December Information Technology Tertiary Institutions 2 October

January 2007 Legal and Management Young Engineers 2 November

February 2007 Awards International Projects 15 December

Artic les may be sent to the chair of the branch/division, to the contacts above, or direct ly to the editor, Sarie Moolman, at [email protected] . Visitwww.civils.org.za/pdf/article_outline.pdfto view a suggestedoutline for your article(s), as well as important information about length of the ar ticle, photoformat, etc

D-dates for submissionsDivisions, branches and other contributors, please note the following deadlines for submissions to the

magazine, and the relevant features. Why dont you use this opportunity to showcase your latest project(s)?


4/43Civil Engineering| August 2006 3

WE LIVE IN A WORLD generally ruledby words on paper. Protocols, agreements,contracts, codes of conduct, codes of ethics reams and reams of paper to be filled in,signed, and abided by.

But do we really live by the rule? Do wereally stop to read the fine print? Everydayexperience proves that the answer to thisquestion is unfortunately most likely not. Itwould seem as if the intrinsic value systemsaccording to which we are brought up nowa-days have not only been diluted, but haveregrettably also disappeared in many ways.

The world is certainly changing, yes, and

value systems will of course adapt accord-ingly, but core ethics are not negotiable.

In the light of this, and in an attemptto re-focus ourselves regarding what ourprofession stands for, a new SAICE Code ofEthics was developed recently and has nowbeen incorporated into our bylaws.

In this magazine a copy of the said newcode is enclosed. We are presenting it inan attractive format that will hopefully en-courage our members to:

Read itDisplay it in their officesTell non-members about it

Inform communities, clients and em-ployers that this is what they believe inand how they do businessInclude suitable clauses in contracts andletters of employment/appointment thatclearly indicate expected behaviour inthe world of civil engineeringMentor young people to inculcate a pro-fessional approach to their work

Our SAICE Code of Ethics is truly a matterof the mind and of the heart!

Over the next few months we intend todedicate some energy and space to assistand encourage our members to LIVE ourCode of Ethics. We also invite membersto contribute anecdotes, stories and casestudies of the good, the bad and the ugly,so that all of us can learn and move for-ward with this important aspect of our livesand of our profession.

O P I N I O N

What distinguishes a profession?

It would seem as if the intrinsic value systems according to which

we are brought up nowadays have not only been diluted, but have

regrettably also disappeared in many ways

Text Dawie BothaExecutive director

SAICE



TRAINING GROUND FOR MANAGEMENTThe foundation for Johns strategic abilitieswas laid at a youthful age in the military. Theorganisation and structure of the military,

especially the emphasis on strategic detail,made it the ideal training ground for manage-ment. I was conscripted to the army straightafter school in 1969, where I suffered basictraining like most, and then went on tobecome unit quartermaster at the age of 21.

As you move up the officer ranks you getvaluable training in strategic skills. I thinkmy experience as a young man, having toplan the logistics that went with moving menaround in the field and keeping suppliesflowing, gave me an excellent footing onwhich to expand later in life, he says.

Since commando service was a part-time activity, it ran parallel to his universitycareer. He obtained his BSc degree in civilengineering at Natal University in 1972 andimmediately went on to do a masters underProfessor Ken Knight. Like so many civilengineering students of that era, John was

enormously inspired by Knight. His aca-demic approach to engineering motivatedme to understand cause and effect relation-ships. I became acutely aware of the im-

portance of understanding and describingthe ways systems behaved, especially engi-neering systems, in terms of being able tosolve problems, he says.

During his postgraduate years he alsolectured in soil mechanics and founda-tion engineering. I loved teaching, but itshard to describe exactly what gave me theimmense satisfaction I derived from it. Itwas probably because I was able to impartknowledge to others and see young minds though I wasnt much older than theywere absorb it and become knowledge-able. It was also satisfying to see someof the students that I had taught becomeprominent figures in geotechnical engi-neering later on.

To get a grasp of the contracting busi-ness, John joined Frankipile in 1975. I wasthrown in at the deep end of the rough

and tough of engineering, working as a

site engineer on the Richards Bay iron andtitanium project. At the time it was prob-ably one of the biggest piling contractsin the country more that 1 500 pileswent into that site. Fortunately I was ableto catch on fairly quickly to the needs tooptimise the way in which work was doneon a construction site in order to minimisecosts. So I learnt a very simple lesson, butnevertheless the most important lesson inconstruction, namely how to plan aheadand do things efficiently in order to makethe contract profitable and come on streamon time.

Another project that he remembers wellwas the Umlaas canal bridge adjacent toDurban airport. It was the first project inSouth Africa where we used reverse circula-tion drilling under slurry to form 1,2 mdiameter piles down to depths of 40 m. It

Test Lorraine [email protected]

Its all about wanting to see

whats outOne will find no special mention of achievement or award in John

Wates professional rsum. I find it difficult to talk about myself,

he says. Im too restrained a person. But talk to present and former

colleagues and it becomes evident that he is regarded as an expert

strategist and an authority on waste management and environmental

geotechnics, having been responsible for the design of numerous

mine tailings storage facilities and industrial and domestic waste

disposal sites. Lorraine Fourie spoke to John at the offices of Golder

Associates Africa where he is business development director and

is simultaneously keeping a sharp eye on the running of specialist

waste, tailings and environmental projects

Environmental assessment for a gold mine in

the Democratic Republic of Congo, 1992



was a very unusual technique that had beenintroduced from Europe and Frankipilewere the first to apply it, he recalls.

STEPPING INTO THE VOIDJohn then took what he considers animmense step into the void. In 1977 heenrolled for full-time MBA study at theUniversity of Cape Town, much againstthe advice of most of the people I knew,who thought I should stick to my career. Inthose years it was not so common a quali-fication as it is nowadays. It was a hugesacrifice because I had to stop working anddepend on my wife to support me.

John, of mixed Welsh, English andIrish stock from the Eastern Cape, hadmarried his university sweetheart, MargoBraak from Pretoria, who traces her rootsback to the early Dutch settlers. She hadcompleted her BCom and we got married in1974 while I was still finishing my masters.Fortunately we didnt have any children yetwhen we went down to Cape Town, andshe managed to get a job and helped me getthrough a very difficult year.

He fared reasonably well, he says, asdid most of the engineers on the course. Theaccountants used to get most irritated withus, because they thought they were smartat business matters the MBA being a verynumerative type of course but the engi-neers were of course analytically quite welleducated.

After that I probably took one of thegreatest decisions of my life. Of our classof about 72 approximately a third were en-gineers, and I was the only one to go backinto engineering. I decided to combine thelittle bit of business training Id got throughthe MBA with the background that I hadthrough my MSc studies. He never lookedback and considers it one of the best careerdecisions he has made. I love engineering;theres never a dull moment. Its a creativeand challenging profession and Im very

sad to see how very few young people takeit up these days.

John and Margo left Cape Townwhen he took up a position with Jones& Wagener Consulting Engineers in

Johannesburg in 1978. They had estab-lished that I had an MBA qualification andcontacted me for a job in mine tailingsengineering, which was a rare thing inthose days. There werent very many tail-ings engineers around. In spite of being ageotechnical engineer, I had never heardof tailings, but I learnt quickly under theguidance of Fritz Wagener, who was a greatmentor and taught me how to think aboutengineering problem solving. Within acouple of months I had designed my firsttailings dam at Vaal Reefs gold mine. Thatwas a great challenge because it happenedwhile Fritz was overseas and I had to do itwithout his help.

Recently John has had the opportunityto assess the work he did as a novice tailingsengineer. That very facility at Vaal Reefshas been decommissioned and is now beingreprocessed, and Ive had the opportunity to

look at some of the structures we put in atthe time and havent seen for so many years.Im not physically involved, because it isntan engineering project, but Anglo Americanis still one of my clients and I get feedbackon the reclamation. Its so interesting to seethe old structures that we built being ex-posed, and learn how they have performed.Thats another thing that makes engineeringfascinating to be involved over the full lifecycle of a project and see whether your de-sign actually stood up to the test, performingaccording to the way you thought it shouldhave, he marvels.

Fritz Wagener remembers John as aperson who always gave his best to hisclients. During his seven years with them,

John handled both tailings and geotechnicalprojects. These two go together and itsunfortunate that there are very few tailings

engineers today who get exposed to puregeotechnical engineering as much as I did,

John remarks. Having been offered a direc-torship at age 31, he probably would havestayed with Jones & Wagener for the rest ofhis life if the independence bug didnt bite.Yes, it was with great regret that our pathsseparated, but he always remained loyal tothe partners he left behind, Fritz says.

BUILDING A BUSINESSWell, I simply had to see whether I couldbranch out on my own and build a busi-ness from scratch. It was all about wantingto find out whether there was somethingelse out there, some other challenge andexcitement. This proved to be true. In1986 John formed Wates and Wagner (with

Johan Wagner), which in 1991 mergedwith Meiring and Barnard to become

Wates, Meiring and Barnard, with Johnas managing director. We became quite asubstantial consulting practice, with a staffcomplement that has now grown to about170 people, specialising in environmentalsciences, geotechnical engineering, tailings

and wastewater.Reflecting on those early days, John says

its difficult to build an organisation. Itssuccess lies in attracting the right people toconsulting, because there are not so many ofthem around people who are highly spe-cialised, committed and good at their work.So I cottoned on to the idea of alliancing.

In establishing work relationships withseveral other companies John found thatthey could deliver a better and broaderservice to clients. But these alliances hada second spin-off. In time, many of thealliance partners found that they enjoyedworking with like-minded people, so muchso that they joined our organisation andhelped to grow it. This is a technique thatI reckon we have just about perfected.Many people try their hand at it, but to getit right you have to develop what I call an

P R O F I L E

there



abundance mentality. If youre going to workclosely with another company you must beprepared to give something to get somethingback. Its the giving away thats difficult andI think thats why a lot of people fail. If anabundance mentality does not exist, withtime one of the alliance partners tends toencroach on the territory of the other andin so doing violates the understanding ofno competition. Youve got to be strict aboutthat; youve got to manage it internally.Everybody in the company must understandwhat the rules of the game are to make itwork. We have been good at it because ourcommunication around it has been good.

VISIONARY AND STRATEGISTA major accomplishment for John was thedeal brokered with the international Golder

Associates Group in 2002 to purchase thenetwork of alliances he had helped build

over the years, operating under the Wates,Meiring and Barnard Trust.

In consolidating the transaction, asister company, Zitholele Consulting, wasestablished to give effect to black economicempowerment. Zitholele was already part ofour family through Solly Manyaka of majoralliance partner Manyaka Greyling Meiring.

Apart from serving the purpose of empower-ment through enterprise formation, Zitholeleis also a vehicle through which we can helpgrow and mentor young, up-and-comingblack professionals, John explains.

He regards it as one of the highlights ofhis life to have formed long and lasting rela-tionships with key people who have workedin his organisation to this day and whom hecan call his close colleagues and friends.

Such a friend and colleague of morethan 15 years is Fred Sutherland, a man-aging director at Golder, who says Johnhas been highly instrumental in buildingthe company to where it is today. One of

Johns strongest points is that he has a veryclear vision of where the industry is goingand how a company such as ours shouldposition itself. For instance, he saw the

environmental market opening up beforemany others did, so he positioned us wellto take advantage of it at an early stage. Hesalways been the strategist and has guidedus as an entity.

Fred has come to know John as aperson with strong principles, which he ap-plies not only in the business environmentbut also in his personal life. You alwaysknow very clearly where you stand with

John. He knows where hes going and hesteers a clear path to get there.

John himself admits to be peeved by lackof commitment. It gets to me if people dontgrasp the opportunities that are given tothem. But then, I believe in management bygentle persuasion and by setting an examplein perseverance. I never give up. In fact, Ihave in my office a saying that I subscribeto: I CAN, which is derived from I Commit,

Assume responsibility and Never give up.Being responsible for strategic and busi-

ness development at Golder Africa, John iscurrently exploring prospects in Africa. Wedo business with most countries in Africa,specifically the major mining companiesoperating there. We have offices in all of thecontinents, which provide an opportunity forour people to broaden their experience. I ampersonally quite involved in South America,which I find particularly stimulating.

On that continent he is applying hisknowledge of tai lings disposal to big copperprojects in Chile. Ive developed two areasof specialisation that are my particularpassion, he says. One is paste technology,which involves drying out mine tailings byfiltering or thickening it to the consistencyof toothpaste before pumping it under highpressure to disposal sites. Apart from savingwater, which is a huge environmental ben-

efit, the waste is rendered less threatening tothe groundwater environment since seepageis either eliminated or much reduced. I wasfortunate to have gained my experiencethrough exposure to one of the first full-scale applications of paste in the world forgold tailings in Tanzania, where Ive beenthe professional engineer of record for themining company ever since.

His other passion is his vision onsustainable development and how its bestapplied through engineering projects.

As chairman of the Golder AssociatesSustainability Council hes been instru-mental in developing an approach for thegroup that is applied worldwide throughtheir offices in 47 countries. I have a teamfrom around the world who work on under-standing the concept of sustainable develop-ment and turning it into a practical notionthat can be implemented throughout theorganisation. We already offer sustainabilityservices to many of our clients, in particularin the mining industry. So the techniquesthat weve developed are now being appliedby a number of mining companies in theworld, he notes with satisfaction.

Within SAICE John was a foundingmember of the Environmental Division inthe early 1990s and later also chairmanand treasurer until he retired at the end oflast year. I had been there for so long thatI though I must give some other people achance, he laughs. Hed also been with theGeotechnical Division for ten years, two ofwhich were served as chairman and eightas editor of the division magazine GroundProfile. As a Fellow he remains involved inthe activities of the Institution. Im busyorganising the fourth of a series of confer-ences on mining and industrial wastemanagement for next year. John believesthat the Institutions role is very importantfor civil engineers and technicians. I wouldlike to see SAICE strengthen its learnedsociety role, because I believe it to be itsmost important purpose, he says.

John profiling test holes in the early part of his career, ca 1979

Below: With mentor Ken Knight and partner Peter Day

of Jones and Wagener at SAICE banquet, 1984

Below middle: At the SAICE Conference on Mining and Industrial

Waste Management with Benght Broms, president of ISSMFE, 1987

Bottom: 13 Addressing the audience at the

Bob Laburn Award function, 1998



PASTE1TECHNOLOGY IS now well ac-cepted as both a reliable and cost-effective

backfill method and an attractive tailingsmanagement option for surface disposal. Apaste conference was held for the first timein Europe (Ireland) in April 2006. Thiswas the ninth seminar in the successfulseries that has already attracted hundredsof vendors, consultants and mine opera-tors from Chile, Australia, Canada andSouth Africa.

The use of paste technology for surfacedisposal is an extension of thickened tail-ings disposal developed 30 years ago byRobinsky in Canada. When he first sug-gested the placement of tailings with littleor no bleed water, the equipment for thepreparation and transportation of it wasnot yet available to realise his innovativedesign. Improvements in the technologyhave gathered pace and a number of manu-facturers now market paste thickeners that

have achieved reasonable success across awide variety of mineral wastes.

Historically, the relatively large portionof liquid in a slurry waste has demandedthat its containment and recovery formthe core of the design philosophy ofalmost every major mineral processingoperation (ie, tailings impoundment). Theadvantages of removing water from a tail-ings disposal facility are many, not leastthe reduced environmental risk associatedwith the lack of transport medium tocarry contaminants from the site in theevent of a failure. For many years, it hasbeen recognised that dewatering the wastestream brought with it many inherent ad-vantages. These include:

Reduction in airspace requirementsReduction in geotechnical hazards asso-ciated with containment structuresReduction in short- and long-term li-ability

Increased recovery of expensive processminerals

Increase in siting and operational flex-ibility of storage facilities, andSignificant water conservation potential

In this article we offer an overview of thelatest trends in paste and thickened tech-nology as presented at the PASTE06 confer-ence in Ireland.

PASTE06 CONFERENCEOver 30 technical presentations werepresented during the three-day seminar,all published in a hard-backed volumeof proceedings. A plenary session fromEuromines opened the conference anddiscussed the impact of increased regula-tory scrutiny from an industry perspective.Keynote speakers included: Ted Lord ofSyncrude, who talked about surface pastedisposal experience in Canada; DaveLandriault of Golder Paste Technology

TextJaco SnymanGolder [email protected]

Michelle TheronUniversity of the [email protected]

O N T H E C O V E R

The latest trends

in paste technologyAn overview


9/43


Limited (Canada), who talked of his 25year battle to have paste backfill acceptedas a legitimate and cost-effective backfillmethod (he won, by the way!); and PeterScales from the University of Melbourne,who talked about the thickening process.

The remaining papers presented atPASTE06 conference were grouped intofour main subjects that covered the mostimportant areas of paste technology. Theseconsisted of:

Thickening and rheologyTransportPaste backfillSurface disposal

Various case studies were presented wherehigh density thickened tailings were em-ployed for surface disposal or are in anadvanced stage of implementing the tech-

nology. It was demonstrated that the tech-nology could be applied equally successfulto new and old operations. At a number ofoperations, particularly in Canada, existingconventional ta ilings management opera-tions have been successfully convertedto high density thickened tailings opera-tions. It also became apparent that surfacedisposal of paste is a viable alternative in

hostile circumstances. Improvements in theunderstanding of post-deposition behav-iour of thickened tailings on surface weremade by means of extensive monitoringand testing that is occurring at some sites.The risks posed by potential liquefactionand instability by surface deposition ofpaste, were highlight. Experienced gainedover the past decade enable designers torecognise these ri sks at an early stage anddesign accordingly.

Cover systems constructed on poten-tially acid forming tailings facilities orwaste rock dumps should act as a barrierto oxygen and water ingress to prevent acidmine drainage. The possibility of using amixture of waste rock, tailings and slag toconstruct a high-quality barrier cover wasinvestigated. Laboratory tests carried outon the material indicated that it could bea viable option. The preliminary results

of large-scale lysimeters were positive andmonitoring will continue for an additionalseven years.

The successful application of pastetechnology as an underground backfill wasalso reported. Application of it as backfillmaterial reduced number of seismic activi-ties and prolonged the life of mine as thenumber of ore pillars is reduced. It should

be noted that preventative maintenance isrequired to prevent plugs in boreholes.

Advances in thickener technology werediscussed. Interesting developments in theability to pump higher and higher yieldstress materials using centrifugal pumpswere reported.

Other attractions at the seminar in-cluded a short course on rheology and thesurface disposal of paste and thickenedtailings. A couple of interesting site visitswas arranged that demonstrated both pastebackfill and the surface disposal of paste.Finally, the organisers have to be congratu-lated on a fantastic social programme thatallowed the conference attendees the oppor-tunity to experience true Irish sounds andhospitality.

CLOSING REMARKSPapers published and presented at

PASTE06 indicated that paste technologycould be successfully applied. Muchprogress has been made in the developmentand understanding of the technology.

NOTE1 Paste can be defined as a single-phase combi-

nation of water and solids that has negligible

excess water when left to rest.

Left: Yummy paste, just like chocolate approaching



WATER IS A SCARCE resource in SouthAfrica, and also in Cape Town. For morethan a century there have been periods ofwater restrictions followed by the develop-

ment of new schemes to expand the cityswater supply, usually through the buildingof a dam. Until 1995 the focus was prima-rily on managing the supply of water withnew schemes being developed to meet thegrowth in water demand.

Cape Town is a growing city of ap-proximately 3,2 million people and it isexpected that in the coming years it willcontinue to grow and to consume morewater. Not only because we will have morepeople, but because the South Africaneconomy is also growing. Research thattakes into account demographic shifts,including the impact of HIV/Aids andmigration of people to Cape Town, showsthat demand is set to grow.

The City of Cape Towns approach towater demand management is based onthree broad principles, namely that water

is a strategic, precious and scarce resource;that there should be no wastage of water;and that all water used should be measuredand accounted for. The principle of meas-

urement is critical to ensure that water ismanaged effectively as a strategic, preciousand scarce resource.

The City of Cape Town recognises thatif its inhabitants are to make use of theirwater resources is a sustainable manner,they will have to carefully manage growthin water demand and look at ways in whichthey can reduce demand, primarily bychanging the behaviour of consumers ofwater and implementing projects that uti-lise an alternative water resource.

Some alternative water resources are thedesalination of sea water, exploring deepaquifers, or the reuse of treated waste water sewerage to name but a few.

Two thirds of the citys water consump-tion ends up in more than twenty treatmentworks across the city, from where the finaleffluent is discharged back into the envi-

ronment. The opportunity of reusing thetreated effluent has not yet been fully de-veloped. The majority of golf courses in thecity are using treated effluent for irrigation

purposes. A limited number of industriesare using treated effluent together with theirrigation of parks and sports fields. Thetotal existing average daily summer reuse is30 Mper day (7% of the total waste watertreated).

More than a year ago the city undertooka project to investigate the refurbishmentand capacity investigations of the treatedeffluent systems at the various waste watertreatment works. The project has beeninitiated with the purpose to increase avail-ability of effluent to the present consumersand also encourage others to use it as alter-native supply to meet their water needs.

Although the philosophy is nothing newand some schemes has existed for morethat 40 years, it was never a formal councilservice and therefore never received a highpriority. The investigation established that

TextLeon PienaarDirectorBVi Consulting Engineers WC (Pty) Ltd

The City of Cape Town bringstreated effluent to the forefront

E N V I R O N M E N T A L


11/43

the potential of treated effluent use couldbe expanded to 170 Mper day (40% of thetotal summer wastewater treated per day) atan average total supply cost of below R2/k.This equals 30% of the annual supply fromthe new Berg River Dam project.

The first extension was completed atthe Bellville waste water treatment worksand increased the available treated ef-fluent by 4 Mper day to 7,0 Mper day.In the 2004/05 financial year a project wasimplemented which increased the reuseof effluent at the Parow and Kraaifonteinwastewater treatment works from 1,2 Mper day to 3,7 Mper day. All the effluentused from the above works replaced po-table drinking water.

POTSDAM TREATED EFFLUENT SUPPLYAND STORAGE SCHEME

A contract for the upgrading of the treated

effluent supply from Potsdam was awardedin June 2005. The project is nearing com-pletion and includes the following:

A new intake chamber with floatingskimmerTwo new pump stations capable of ulti-mately pumping 1 600 kper hour(40 Mper day) to the storage reservoir

A filtration plant removing al l suspendedsolids up to 120 m

A 600 mm diameter bulk supply pipeA 40 Mstorage reservoir constructed ofa earth embankment with HDPE linerand FPP floating cover

Users and demandThe project will increase the treated ef-fluent used from Potsdam by 17 Mper dayup to 24 Mper day. All 17 Mper day willbe replacing potable fresh water. A further20 Mper day will be made available for

agricultural use.The scheme also provides the bulk

infrastructure for future extensions to otherindustrial users and residential develop-ments in the area. A new development onthe farm De Grendel will also utilise thetreated effluent and install a dual water re-ticulation network for domestic irrigation.

All the above projects have orangecolour-coded networks to ensure zerocontamination risk and prevention of con-tamination by controlled splitter chamberconnections and regular inspections (multi-barrier, multi-precaution approach).

The City of Cape Town (Water Services)through a tender process employed BVi

Consulting Engineers WC (Pty) Ltd and aJoint Venture between Peak Projects andPDR Construction for the civil constructionand Tricom Africa for the mechanical andelectrical installation respectively.

THE FUTUREThe feasibilities for further expansion andre-use schemes are being investigated at allother wastewater treatment works withinthe city. It is clear that the scope for furtherdevelopments is promising.

Some of the existing users New users on scheme

Milnerton Golf Course Caltex Refinery

Theo Marais Sportsfields Khynoch

Sappi Paper Agricultural use

Schools in Milnerton and Table View

Public open spaces and Table View beachfront

dunes


Opposite page: The 40 MPotsdam

storage reservoir under construction

Right: Colour coded glass reinforced pipes (GRP)

Bottom right: Compact modular filtration units



GROOTVLEI Proprietary Mines (Pty) Ltd is the last remainingoperational gold mine in the East R and Basin of the Witwatersrandgold fields. Mining in the East Rand Basin has been ongoing overthe last 80 years, and the basin is now largely mined out.

The mine is located in Gauteng, some 25 km east ofJohannesburg. Grootvlei Mine currently dewaters about 75 M/dayfrom its workings in order to maintain access to undergroundreserves, with the pump station located at a depth of 740 m belowsurface. The water is treated to remove primarily iron and is thendischarged into the Blesbokspruit, which flows over the East RandBasin. This discharge is in line with the conditions of the existingwater use license issued by the Department of Water Affairs andForestry (DWAF).

Some of the water pumped from underground is believed tooriginate from surface water. A high proportion of the flow in theBlesbokspruit is the result of industrial discharges, primarily fromfour sewage treatment plants and a paper mill. An investigationwas carried out to identify methods to reduce the volumes of water

required to be pumped from underground, with the first phase ofthe recommended remediation works being carried out.

INGRESS INVESTIGATIONNumerous previous studies on the ingress of the water indicatedthat a significant proportion originated from surface water. In addi-tion, a large proportion of the flow in the Blesbokspruit comprisesindustrial flows (some 205 M/day, compared with 68 M/daynatural flows). It is therefore not unreasonable to assume that re-ducing the flow in the Blesbokspruit would significantly reduce therecharge to the East Rand Basin.

Based on this, a previous investigation suggested the constructionof a canal, 35 km long, to remove the industrial flows from the river.

The ingress volumes show strong seasonality, with summerinflow rates being almost double those in winter. The industrialflows, on the other hand, are largely constant. Field studies showedthe presence of significant clay alluvium along the Blesbokspruit,which would be expected to limit recharge volumes from surface.

Figure 1Ponding in the southern Blesbokspruit Figure 2Ponding at West Pit

Text Mike PalmerJones & Wagener (Pty) [email protected]

Chris WaygoodJones & Wagener (Pty) [email protected]

Irene LeaBema Gold SA

[email protected]

Remediation of wateringress to old gold workingslinked to active mines


13/43


In addition, mining personnel indicated that inflows appear to besignificantly higher in areas of shallow undermining than deeperareas. Removal of the industrial flows would also not reduceponding over much of the catchment, since the ponding is attrib-uted to areas where culverts and road structures have resulted insilting, as illustrated in figures 1 and 2.

This was seen as a major drawback of the canal proposal, inthat after construction, significant problem areas would still remainin terms of surface recharge.

It was therefore decided to identify all recharge mechanismsand to quantify the contribution of each mechanism to the surfacewater ingress. From this it would be possible to identify, evaluateand cost a range of remedial options for reducing the volume ofsurface water recharge.

Investigational workA conceptual groundwater model was required to gain an under-standing of the primary mechanisms of ingress into the basin. Thefollowing assessments were carried out to enable the developmentof a model:

Basin geologyThe geology of the basin and its influence on re-

charge to the workings was considered.Seasonality of ingressHistorical pumping, water level and rainfalldata were obtained. The water level data were used to calculatestorage volumes underground. Ingress volumes could then becalculated and the seasonality determined.Photo surveyAn aerial survey of the catchment was carried outover the length of the mining area to assess its status and theimpact of newer developments such as roads, tailings dams andtailings reclamation activities.

Delineation of areas of shallow underminingObservations by miningpersonnel indicated that any mining shallower than 300 m fromsurface is characterised by significantly increased groundwaterinflows.Alluvium surveyA hand auger survey was undertaken alongthe Blesbokspruit to assess the depth of alluvial clays. It wasfound that clays are present to depths of at least 1,5 m in mostinstances. In addition, there are extensive silt deposits of up toseveral metres depth at some culverts and bridges.Flow measurementsFlow rates were measured underground atareas where inflows could be associated with shallow workingsor a particular geological feature. Surface flow measurementswere undertaken upstream and downstream of areas of potentialingress.Isotope studyMeasurement of nitrogen isotopes indicated thatthere is a link between the industrial discharge (primarily treatedsewage water, thus high in nitrates) and the underground re-charge.

Conceptual modellingGround water modelling usually implies analysis of groundwater

flow volumes using two primary concepts, namely Darcys Law andthe conservation of mass. Mathematical computations can then beundertaken to determine inflows or outflows within a particularenvironment.

Where this is not possible because of limited data, or a highlycomplex site, the problem can be simplified by considering broadareas or components for which a particular recharge or flow is as-sumed or determined from field data.

To a large degree, the second approach was followed. As with any



multi-parameter model, it is possible to simulate the observed resultsby assigning incorrect values to the various components. However, theconceptual model provides an indication of the likely contributionsand the extent to which mitigation measures may be successful.

Each area of ingress was assessed, and the components of thegroundwater balance are summarised in table 1.

Main Reef outcrop where mining has extended to surfaceWhere theMain Reef outcrops on surface, surface and shallow mining hascaused subsidence along the outcrop area (figure 3). Two mainingress mechanisms are associated with this feature the first

is via direct rainfall along the exposed outcrop, and the secondmechanism occurs when surface outcrop areas intersect streambeds.Sub-outcrop where shallow undermining has taken placeThe ingress to

areas of mining shallower than 300 m was quantified using ac-cessible areas where flows could be measured, and extrapolatedto the remaining shallow areas.Structural featuresStructural features tend to be the main conduitfor recharge from the overlying dolomitic aquifer. One fault inparticular, referred to by mine personnel as the rain forest, issituated below a dam (see figure 4). The flow along this fault hasbeen measured and is estimated to contribute as much as 10M/day.Overlying dolomitic aquiferExperience has shown that the base ofthe dolomites is generally very impermeable and inflow to themine workings from the dolomitic aquifer is restricted to geo-logical features linking the two. The inflow from the dolomitesis, however, significant and is expected to be relatively constant,particularly where karstification has been accelerated in the ex-posed areas of dolomite around the Blesbokspruit.

Modelling resultsThe estimated recharge for each component is indicated in table 1.

The model indicated that the primary sources of surface water

Figure 3Old access shafts on outcrop

Figure 4Underground seepage at the rain forest

Figure 5 Remedial works at West Pit

Table 1Groundwater recharge components

Recharge component

Average flow rate (M/

day)

Wet season Dry season

Catchment recharge into outcrop 42,00 7,00

Direct recharge via outcrop 2,53 0,00

Shallow undermining 24,29 24,29

Preferential recharge (geological structures) 10,38 10,38

Recharge via dolomitic aquifer 29,34 29,34

Total 108,54 71,01


15/43

ingress are related to the outcrop and shallow undermining areas.The modelling also calculated the ingress at West Pit, an area of

shallow undermining, to be in the order of 12% of the average ingressfrom surface water. Should remedial works prevent all ingress at WestPit, the overall dewatering rate could be reduced by some 7%.

Proposed remediation optionsBased on the outcome of the modelling, it was decided to focus theinitial remediation measures on the outcrop areas and the areas ofshallow undermining.

In the dry outcrop areas, the extent of faulting makes it difficultto plug the holings. However, much of this area is currently beingre-mined opencast, and will be rehabilitated as part of the miningprocess.

There are a number of areas of shallow undermining adjacentto Grootvleis West Pit, an opencast pit next to the stream andwetland (figure 2). Underground mining in this area is extremelyshallow, being only 7 m below surface in places, and significantunderground seepage is experienced.

A large quantity of silt (mostly gold tailings) has been depositedupstream of a road culvert and appears to cover most of the foot-

print of the wetland. It was important to improve the drainage inthis area to minimise the extent of ponding.

The strategy proposed for this area is to divert low flows aroundthe wetland and to improve the drainage by opening up the down-stream road and railway culverts, allowing the area to dry. Thiswould be followed by removal of the tailings, and revegetation ofthe area. The rehabilitation of the West Pit area was therefore se-lected as the first phase of the remedial works.

REMEDIATION AT WEST PITThe shallow mining adjacent to West Pit is covered by a wide wet-land area that has been created by a combination of environmen-tally poor road and railway construction, flat slopes and tailingswashing from old tailings dams into the stream.

Scope of workConstruction works involved the following (see figure 5):

Construction of a weir across the wetland to direct the industrialflows and runoff up to the 1:5 year event into a low flow canalaround the wetlandThe low flow canal is separated from the floodplain area by aberm and will direct these flows under the roadway via a newculvertThe existing culvert will be opened up and the original streamwill be reinstated, while the area of ponding will be allowed todry outOnce the area has drained, the exposed tailings will be removed

The area will then be revegetated and maintained to prevent thegrowth of large stands of reedsOver the area with the highest risk of ingress, the low flow canalwill be lined with concrete to minimise seepage

The end result is expected to be an open, grassed area which isonly inundated during extreme events, with the low flows re-stricted to a dedicated canal, where the width over which ingresscan occur is significantly reduced.

Challenges encounteredDifficult working conditions on site have presented both the con-sultant and the contractor with a number of challenges.

Access to waterlogged areasVery soft ground conditions have madeaccess to the waterlogged areas difficult. In order to gain accessit was necessary to construct rockfill platforms into the wetlandarea. A woven geotextile is used as a support layer beneath therockfill material. This measure has proved highly successful,with minimal loss of material.Depth of tailingsDuring construction the tailings thickness wasfound to be greater than expected, causing concerns about invert

levels, and the ability to effectively drain the area, given the ex-tremely flat slope on this portion of the stream.Flat slopesThe flat longitudinal slope (in the region of 1:1 000)has resulted in large-scale silting. It was therefore necessaryto excavate a canal downstream of the area to provide a directdrainage route to the main watercourse. The downstream canalis located within a wetland area, requiring the construction ofa rockfill access road on woven geotextile. The flat slopes meanthat this canal will be prone to silting, and maintenance will berequired to keep it open.

CONCLUSIONSThe investigations indicated that a significant portion of the ingressto the East Rand Basin originates from surface water. The mainsources of this water appear to be ingress at the open holings and

subsidence areas at the Main Reef outcrop, as well as from areas ofshallow undermining.

The current rehabilitation will only address one area of shallowundermining, and this could reduce the required undergroundpumping rate by up to 7%. While the works will improve the flowpast West Pit, the reduction in ponding is also partially dependenton the downstream areas being able to drain effectively. Regularmaintenance on the downstream canal will however be required tokeep it clear and maintain the flow.

PROJECT TEAM

Client Grootvlei Mine, a subsidiary of Bema Gold SAConsultant Jones & Wagener (Pty) LtdContractor Trollope Mining Services (Pty) Ltd




THAMES WATER, the UK company re-sponsible for sewer operations in London

and the Thames Valley, needed to find asolution for a problematic drain locatedat Farnham railway station, Surrey. Thedrain in question, which ran beneath a railcrossing at the intersection of WaverleyLane and Station Hill near the Tilford Road

junction, had repeatedly flooded, leadingto major concerns for the company. After

jetting clean the drain, a CCTV surveyinvestigation revealed the cause of theflooding to be extensive root infiltrationand a number of structural defects.

The drain, a vitrified clay pipe, was 70 mlong and 225 mm in diameter with six lateralconnections, several of which were intrudinginto the main bore. It was laid to a steep gra-dient and had a high rate of flow.

Locality was also a significant factorto be considered, as the drain runs alongthe approach road to the railway station.

Owing to the towns location in the south-east of England commuter belt, this makes

it a very busy road during peak periods.Another difficulty was that the upstreammanhole location was within the boundsof the level crossing serving the station atthe Waverley Lane and Station Hill inter-section. This required an interface withNetwork Rail to obtain access to facilitatethe renovation work and manage flowcontrol during the works. Works also hadto be completed overnight so as not impacton the regular day-time services runningthrough Farnham Station.

The complexities of the project resultedin a number of contracting companies ap-proached by Thames Water declining thecontract. However, DBI EnvironmentalServices Ltd of Kemble, near Cirencester,Gloucestershire, confidently took up thechallenge.

After careful consideration of the op-

tions available, it was decided that thedrain should be lined using a UV-curedliner in order to stabilise its structuralcondition. The liner would also act as a rootbarrier to prevent future re-growth andsubsequent new blockages.

LINING SOLUTIONIn view of the circumstances of the site,DBI decided to line the drain using anultraviolet light (UV) cured in place pipe(CIPP) as it had clear advantages over a hot-cured lining system.

The main advantages in relation to thisparticular project were:

A greatly reduced site footprint comparedto using hot cure lining technology, thatis, no requirement for boilers, scaffoldtowers, circulating pumps or refriger-ated trucks. From initial discussionswith Network Rail, it was clear that aminimum amount of impact would beallowed on the level crossing. To erect ascaffold tower within the bounds of thelevel crossing would require a possession

of the railway line, which would havetaken several months planning with in-creased costs due to a large Network Railpresence.

A greatly reduced curing time, estimatedas being around 90 minutes for the UVcure process as opposed to around sixhours for a hot cure liner. DBI was givenonly a six-hour window each night inwhich to carry out the works. Installationand curing would not have been achiev-able in this time using any of the avail-able hot cure liners.There was no requirement for curingwater and its associated disposal prob-lems.

The liner used for the Farnham project wasprovided by SAERTEX multiCom GmbH ofGermany. Based on a glass-fibre material,the liner product utilises, and is impreg-

UV-cured lining work offerssolution to pipeline renovationat Farnham Station

The UV light train used for curing the new liner


17/43


nated with, a photo-initiated polyester orvinylester resin. The liner is available forinstallations from 150 mm to 1 200 mm indiameter, with wall thicknesses from 3 mmto 12 mm, depending on structural require-ments.

Once the liner is in place in the hostpipeline, the resin is cured using a UV lighttrain, which is passed through the inflatedliner at a set speed. The speed of the lighttrain is dependent on the liner diameterand the wall thickness used on any par-ticular installation, but is normally between0,58 minutes/metre (or 35 seconds/metre)and 1,5 minutes/metre. The light trainfor the project in Farnham was providedby specialist equipment manufacturerProKasro GmbH of Germany.

DBI was able to procure both the linerproduct and the UV light source throughthe Saertex and ProKasro UK distr ibutionagent CJ Kelly Associates Ltd. John Kellyof CJ Kelly worked closely with DBI and itsinstallation crew throughout the planningand implementation phases of the work toensure both the liner and the curing equip-ment were readily available as and whenrequired given the tight schedules associ-

ated with the project.As part of the instal lation process, the

invert of the host pipe is pre-lined with aglide foil. This is designed to help the linermaterial winch smoothly into the host pipeduring the initial installation stages.

INSTALLATION PROCESSA typical installation process involves thefollowing steps:

Isolating the section of pipe in need ofrepair and de-watering it.

High pressure jetting/cleaning to remove

The robotic cutter unit with its on-board camera system

and (inset) the control cabin used during the cutting work



debris and dirt that might affect thelining processCCTV inspection to establish fully anyneed for remedial intrusion removal suchas roots or lateral pipe sections and toestablish lateral positions for reopeninglaterInsertion of the glide foil into the pipeinvert to ease the liner installation

Winching the impregnated liner into thehost pipe over the length to be linedInsertion of the UV light train into theliner, sealing of the ends and inflationagainst the host pipe wallInitiating the curing process, passing thelight train through the length of the linerOnce curing is complete and the linerhas cooled, opening of the ends of theliner to remove the light train and winchcablesRe-opening of laterals to complete theinstallation.

PLANNING FOR FARNHAMDBI approached Network Rail to discussand agree working arrangements on thelevel crossing. Subject to approval of site

specific risk assessments and method state-ments, Network Rail stipulated a number ofconditions within which the works had tobe carried out.

An appointed crossing guard was to be inattendance at all times, who would deter-mine when DBI could workNo operatives or plant were permittedwithin the level crossing during trainmovementsNo scheduled train movements wereanticipated between 11:45 pm and05:45 am, however this did not accountfor the movement of engineering trains,etc. DBI was therefore only permitted toplace plant on the crossing for a brief pe-riod of time under the supervision of thecrossing guard

This meant that flow control would haveto be achieved using tankers and that all

lining plant had to be located outside of thelevel crossing area. Traffic management alsohad to take into account the location of thelevel crossing.

To solve the problem of the cablesrunning from the cutting and lining rigsduring the works, a system of pulleys wasdevised to ensure that they would rununder the level crossing gates even if theywere shut. The work was programmed to becarried out over three consecutive nights.From the site survey it was estimated thatthe lateral connections were of sufficientlength that they could remain blocked offfor up to 24 hours without affecting theproperties that they served. To make surelocal people were kept up to date and pro-vided with information about the work, aleaflet drop was made.

OPERATIONAL INSTALLATIONThe programme of works was completedover three nights.

Night 1In the six hours available, all pre-instal-lation preparation work was carried out.

The drain was jetted from the downstreammanhole and a CCTV survey carried out.The robotic rig was then positioned andutilised to remove any remaining roots,cut back the intruding lateral connectionsand smooth out any displaced joints. Theposition of the lateral connections was thenplotted and recorded for reference duringthe re-opening operation. All preparationwork was completed within the allocatedtime.

Night 2The drain was jetted from the downstreammanhole to ensure it was clean to installthe liner. A final pre-lining CCTV surveywas also carried out to ensure the drainwas ready to line. The guide rollers werethen installed and the glide foil pulled intoposition. The resin impregnated liner was

then pulled into the drain with a winchand the downstream packer and end capfitted along with the draw cord for the lighttrain. The liner was then part ially inflatedusing compressed air from an inlet in thepacker. This allowed the light train to beinserted.

The liner ends were sealed withpackers. The liner was then fully inflated toits correct pressure to ensure a close fit tothe host pipe inner wall and the UV lighttrain was pulled into position for the startof curing. The UV lights were switched onand curing commenced with continuousmonitoring.

The curing process required the UVlight train to be pulled through the resinimpregnated liner at a steady rate of ad-vance to ensure that the resins cured evenlyand effectively. With the liner used atFarnham, comprising a 6 mm wall thick-

ness Polyester UV resin impregnated mate-rial, the advance rate required for the lighttrain was calculated at 56 seconds/metre.

Once curing was complete, the lighttrain was turned off and allowed to cool in-side the lined drain. When the monitoringsensors showed that the liner had cooledsufficiently, the packers were removed. Thelight train followed along with all other an-cillary items. Again all work was completedwithin the allocated time.

Night 3The robotic rig was positioned and alllateral connections re-opened. The endsof the liner were trimmed and a final flushand CCTV inspection were carried out. Theduration of this work was just four hours.

CLOSING REMARKSIn relation to the Farnham work, Dr SteveOvington, business development directorfor DBI, said: This project has been a suc-cess on several fronts, not least the manage-ment of various stakeholder expectations.The asset owner, Thames Water, has beenable to rehabilitate a drain which has given

repeated problems. Network Rail, theowner of land and assets within which thedrain is located, has incurred no damageto property and a minimum of disruptionto its services. Domestic householdersconnected to the drain have experiencedno interruption to their normal supply. Allin all, the project has been well planned,managed and executed and DBI is proud ofthe efforts of our delivery team.

INFO

DBI Environmental Services Ltd

T +44 (0) 1285 772300

[email protected]

CJ Kelly Associates Ltd

T +44 (0)1832 293030

[email protected]

The Farnham drain before lining with root intrusions and pipe defects and after lining with all blockages removed and laterals reopened

To solve the problem of the cables running from the cutting and lining rigs

during the works, a system of pulleys was devised to ensure that they would

run under the level crossing gates even if they were shut



THE RECOGNITION that worker health,safe working practices and environmentalconservation (HSE) have become an obliga-

tion and not a choice remains pivotal tothe pursuit of global best practice in South

Africas bituminous products industry.Driven by the Southern African

Bitumen Association (Sabita) and itsCentre for Occupational Safety, Health andEnvironmental Conservation (COSHEC),this commitment to HSE is underpinnedby an ongoing campaign of technology de-velopment, risk assessment procedures andsafe working practices designed to instil aculture in which profitability is not pursuedat the expense of employee wellness or thefragility of the environment.

This approach dictates that the pros-perity of involved companies and organisa-tions be placed at all times side by sidewith the needs of the people and the planet a direction that is key to Sabitas commu-nications programmes with its members.

HSE is a key strategic cluster in the currentbusiness plan of the association, and opera-tions in this arena are funded by dedicatedallocations received from the primaryproducers of bitumen the oil companies,said Piet Myburgh, chief executive officerof Sabita.

While industr ial health and safety islargely a product of appropriate workingprocedures, preservation of the environ-ment centres on the development andresponsible use of environmentally friendlyproducts. To foster broader acceptance andimplementation of these principles, Sabitahas launched several initiatives, the mostprominent of which are discussed here.

DISCONTINUATION OF THE USEOF COAL TAR PRODUCTSCommonly used until recent times forpriming bases and precoating aggregatesduring road construction, the proven car-cinogenic properties of coal tar productshas resulted in their almost universal ban-ning and replacement with bitumen-based

alternatives. Bitumen is obtained from thedistillation of crude petroleum oil importedto meet the countrys liquid fuel energy de-mands. At ambient temperatures bitumenis non-toxic, non-volatile and resistant towater and weathering, flexible, generallyodourless, and serves as a good insulatorand adhesive.

Coal tar, however, is a condensation by-product obtained from the gassification ofcoal. The carcinogenic hazards inherent inthe use of coal tar products arise from thehigh concentrations of polycyclic aromatichydrocarbons (PAHs) in both low and hightemperature coal tar products. Identified aseither acute or chronic, these hazards havebeen widely acknowledged since 1985.

Coal tar products also pose seriousenvironmental hazards, both in their usageand in the disposal of wastes. Their leach-

ability is far greater than that of bitumen,posing a higher threat to surface andground water supplies, and to microbio-logical systems. This threat is heightenedby the fact that coal tars contain com-pounds of substantially lower molecularweight than bitumen, including phenolsand other aromatic compounds, many ofwhich are liquid at ambient temperatures.

Myburgh noted that despite widespreadawareness of the health and environmentalhazards inherent in the use of coal tarproducts, and the fact that their use hasbeen prohibited in countries throughoutthe world, none of South Africas 248 mu-nicipalities nor any of the six metropolitancouncils have taken heed and precludedthe use of coal tar binders in their built-upenvironments, where the exposure levelsand therefore the concomitant ri sks are farhigher than in the rural environment.

Currently, only the South AfricanNational Roads Agency (Sanral), theProvincial Administration Western Cape(PAWC) and the Gauteng Department of

Public Transport, Roads and Works haveheeded the call to ban the use of theseproducts on their projects, said Myburgh.

He pointed out that cost-effective, non-toxic bitumen-based alternatives to coal tarproducts for road construction were readilyavailable both for priming base layers andprecoating surfacing chips.

Despite the intention of some provincialroads authorities to discontinue the use ofcoal tar products, Myburgh noted, thesewere still, in some cases, being specifiedby consulting engineers and preferred bycontractors.

This is a problem demanding imme-diate and urgent attention, he said. It isinconceivable to an association like Sabitathat professional engineers, perhaps mem-bers of SAICE, should continue to specifyhazardous and unhealthy products for road

Focusing on the preservationof the environment

Together with global stakeholders such as

Eurobitume, EAPA, the Asphalt Institute and

NAPA, Sabita co-sponsored an international

symposium held in Dresden in June this year,

when expert scientists presented peer-reviewed

papers on, inter alia, epidemiological and inhala-

tion studies of bitumen fumes. Co-organised

by the American Conference of Government

Industrial Hygienists (ACGIH) and the Deutsche

Forschungsgemeinschaft (DFG), it is believed

this conference will assist the International

Agency for Research into Cancer (IARC) to in-

corporate current knowledge into a monograph

on bitumen fumes, expected to be issued in

September this year.

The symposium outcomes, to be supported

by a 2,2 million IARC study to examine the

contribution of confounding factors such as

past exposure of workers to coal tar fumes and

vapours, and contributing lifestyle factors. It is

anticipated that this study will corroborate the

findings of past research, which has established

that there is inadequate evidence that bitumens

alone are carcinogenic to humans. Sabita will

assess these findings and their impact on policy

and practice in South Africa.

This is a problem demanding

immediate and urgent attention.

It is inconceivable to an association

like Sabita that professional

engineers, perhaps members of

SAICE, should continue to specify

hazardous and unhealthy productsfor road construction when global

conventional wisdom has led to

the widespread substitution of this

product with safe alternatives


20/43

construction when global conventionalwisdom has led to the widespread substitu-tion of this product with safe alternatives.

We should like to encourage the civil engi-neering profession in South Africa to alignitself to global best practice in this respect.

BITUMEN WASTE DISPOSALMounting proof that bitumen presentedminimal hazard to either users or theenvironment prompted Sabita during2003/04 to conduct a campaign for pen-etration grade bitumen to be de-listed as ahazardous waste, and for waste disposal tobe permitted at certain designated generallandfill sites.

Sabita subsequently investigated theavailability of suitable permitted wastedisposal sites that would both encourageenvironmental responsibility and promotecost efficient waste disposal. Initially under

the control of the Department of WaterAffairs and Forestry (DWAF), responsi-bility for waste control has now shifted tothe Department of the Environment andTourism (DEAT), which has taken over thepermitting role from DWAF as from3 January 2006. A waste control section isin the process of being established for thispurpose, and Sabita is maintaining contactwith the relevant government authorities to

resolve any outstanding issues.A total of 21 sites have been approached

with the view to allow permitting for thedisposal of penetration grade bitumen. Thisincludes eight in KwaZulu-Natal region,three in the Gauteng region, three in the

Western Cape region, six in the EasternCape region and one in the Free StateRegion.

In a related initiative the minimalhazard presented to the environment bypenetration grade bitumen compliant withSABS 307 resulted in its re-classification forroad transportation. The inclusion of pen-etration grade bitumen in the requirementsof transportation code UN 3257 alignsSouth Africa with international practice.This classification will ensure that the ap-propriate transportation emergency cards(Tremcards) are carried in the vehicle, thusensuring appropriate action in the case of

an incident.Increasing pressure on resources

human, financial and natural de-mands that sustainability be placed higherand higher on our governance agendas,Myburgh concluded. This dictates that theactivities of the bituminous products in-dustry be directed at current needs, such asimproved efficiency, without compromisingthe the quality of future resources.

22 Civil Engineering| August 2006

SAICEAWARDSFUNCION

Tursday12 October

2006


21/43


THERE IS A GLOBAL DRIVE towardsfinding sustainable, environmentally con-scious solutions to water resource manage-ment problems such as the treatment ofmine wastewater.

Population growth, industrial develop-ment and climate change are some of theforces placing increased pressure on al-

ready limited water resources, and the needfor integrated water resource management(IWRM) has become urgent and critical.

This need is further highlighted by the re-quirements of the National Water Act (1997),which include that polluted water be treatedbefore it enters any receiving water body.

In the mining industry one of the largestenvironmental problems and challenges isacid mine drainage (AMD) and brines. Since

the environmental impact caused by AMDand brines can be severe, it creates liabilityfor mines long after mine closure.

An option that has been both investi-gated and fairly well documented is the useof wetlands, whether artificial or natural, inthe treatment of mine wastewater, yet therehas been only a limited application of this

technology thus far, both nationally andinternationally.

This may be because the complex struc-ture and function of wetland ecosystems ispoorly understood, as is the variability ofthese systems, making wetlands difficult tomanage and/or reconstruct for the purposesof wastewater treatment.

Since system modelling and systemsthinking integrates so-called hard sciences

such as ecosystem structure and functionand soft sciences such as socio-politicaland management issues, it can be usedsuccessfully in integrated water resourcesmanagement.

In applying systems modelling andsystems thinking to wetlands, it may bepossbile to characterise the ecosystem

structure and function in an integratedmanner in order to construct a predictivesystems model.

Once this has been done, the manage-ment and/or reconstruction of wetlands forthe purposes of mine wastewater treatmentmay finally be within reach, providing asustainable, cost-effective and environmen-tally conscious solution to wastewater treat-ment on mines.

Text Petro VosSenior environmentalist

Jeffares & Green (Pty) LtdT [email protected]

Integrated water resources managementinvolving wetlands as wastewater treatmentalternatives on mines



THIS IS THE SECOND article on liabilityand has come about as a result of a concernexpressed by one of our members in thecivil engineering profession.

The member expressed the view thatcivil engineering professionals believe theyare protected against personal liabilityfor design errors when practising under aPropriety Limited ((Pty) Ltd) company, aLimited (Ltd) or public company or a CloseCorporation (CC).

Why, in the opinion of the writer, thisis considered irregular and although notprohibited by statute in the engineeringprofession, it is expressly prohibited inmany other professions.

Furthermore, the writer would liketo see the civil engineering design pro-fessionals brought into line with otherprofessionals who bear huge responsibili-ties through the work they undertake, bychanging the rules which govern civilengineering professionals by inserting anexpress prohibition to practise under a CC,(Pty) Ltd, or a Ltd company, and make itcompulsory to have professional indemnityinsurance for each individual before under-taking any design work.

THE CONCEPT OF A COMPANY1

When a company is registered, in whateverform, this body takes on a separate legalpersonality and it acquires its own rightsand liabilities. It is a legal person (legal per-sona) and is separate from its share holdersand directors. The directors or memberstake care of the management of the com-pany. The benefits of a company is that its

financial liability is limited to capital con-tributed to it. There is a limited financialrisk and does not afford the design profes-sional any protection against personal li-ability for design errors, whatsoever.

The company as a legal persona can bea party to a contract and sue, and be suedin court, however since it does not have aphysical existence, these actions are under-taken by the organs or agents (directors) onits behalf.

THE CORPORATE VEILThe company, as a legal person, exists as aseparate entity from its directors or mem-bers. This separate existence is, by way ofmetaphor, conceived as a veil separating thecompany from its members and concealingthem from those who deal with it. This isoften referred to as the corporate veil.

The separate legal personality of a com-pany is a matter of substance, not a meretechnicality, and therefore special or excep-tional circumstances must exist before thecourt will pierce the veil.2

The term veil piercing is used looselyto refer to looking behind the corporate veiland occurs when, for the purposes of thisarticle, the directors or members are to beheld personally liable for design errors orerrors of judgment.

The courts are usually reluctant topierce the corporate veil. The general ruleis that a court will pierce the corporate veilonly where special circumstances exist in-dicating that it is a mere faade concealingthe true facts, that is, where the separateexistence of the company is being used toperpetrate fraud, fraud being used in awide sense, for example to absolve a designprofessional of any personal liability. Theseparate existence of a company will notprovide a design professional with any pro-tection against personal liability nor will itconstitute a defence should the design pro-fessional be faced with personal liability.

COMPANIES ACT3AND PERSONALLIABILITYSo how does the Companies Act3deal withpersons such as design professionals whowish to form a company, benefit from alimited financial liability, not abuse theseparate corporate identity and still remainpersonally liable for their own designs?

The answer is to be found in section53(b) of the Companies Act,3which readsthat:

53 The memorandum of a company [may](b) in the case of a private company, pro-

vide that the directors and past direc-tors shall be liable jointly and severally,together with the company, for suchdebts and liabilities of the companyas are or were contracted during theirperiods of office, in which case the saiddirectors and past directors shall be soliable.

The Close Corporations Act4does not havea similar provision.

OTHER PROFESSIONS

Attorneys Act5

This Act provides as follows under section 23:(1) A private company may, notwith-

standing anything to the contrary con-tained in this Act, conduct a practice if

(a) such company is incorporated and

registered as a private company underthe Companies Act, 1973 (Act 61 of1973), with a share capital, and itsmemorandum of association providesthat all present and past directors ofthe company shall be liable jointly andseverally with the company for the debtsand liabilities of the company contractedduring their periods of office

This complies with the requirements ofsection 53(b) of the Companies Act.3In the

circumstances an attorney may not practicehis profession under a (Pty) Ltd and, byinterpretation, neither a CC. An attorneypractising his profession under a privatecompany is required to be an Incorporatedcompany, usually abbreviated Inc(Afrikaans, Ing).

Public Accountants and Auditors Act6

This Act stipulates in section 21:(1) A public accountant may engage in

public practice by himself or in partner-ship with other public accountants

(3) Persons registered in terms of this Actas accountants and auditors and en-gaged in public practice may in termsof the Companies Act, 1973 (Act No 61of 1973), form a company to engage inpublic practice through its members,provided

(a) the company is incorporated and reg-istered as a company in terms of theCompanies Act, 1973, with a sharecapital, and its memorandum of associa-tion provides that its directors and pastdirectors shall be liable jointly and sev-erally, together with the company, for its

debts and liabilities contracted duringtheir period of office

Once again this section complies withthe requirements of section 53(b) of theCompanies Act3. In the circumstances anaccountant may only practise his or herprofession under an Incorporated com-pany.

Close corporations7

Section 65 of the Close Corporations Act7provides that whenever a court is of theopinion that the use of that corporation,or any act by or on behalf of, constitutesa gross abuse of the juristic personality ofthat corporation as a separate entity, thecourt may declare that the corporation isto be deemed not to be a juristic personin respect of such rights, obligations or li-abilities.

Text Adv Emil van der [email protected]

Liability of professional civil engineers 2

L E G A L A N D M A N A G E M E N T


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Engineering Profession Act8

The Engineering Profession Act is, unfortu-nately, silent on the aspect of engineeringdesign professionals practising as a juristicperson.

Code of professional conduct9

The Rules of Conduct for RegisteredPersons provides under Rules of Conduct:2 Registered persons(s) must ensure that, while engaged as part-

ners, directors or members of a privateconsulting practice operating underthe style of a partnership, a companyregistered in terms of the Companies

Act, 1973 (Act No 61 of 1973), or aclose corporation registered in terms ofthe Close Corporation Act, 1984 (ActNo 69 of 1984), and which performsengineering work of a nature generallyperformed in a consulting engineering

practice, the control over the engineeringwork of the organisation is exercised,and the responsibility in respect of it iscarried, by a registered person other thana person registered in terms of section11(2)(b), 12(2)(b), 13(2)(b) or 14(3)(b)of the Act; and

(t) must, when requested by the councilto do so, in writing provide the councilwith all the information available to

them which may enable the council todetermine which registered person wasresponsible for any act which the councilconsiders PRIMA FACIE to be improperconduct.

With all due respect to the author of theabove clauses, the writer is of the consideredopinion that these two clauses are vague,cumbersome and ephemeral in effect.

It is proposed that these clauses bereplaced by a clause that complies with sec-tion 53(b) of the Companies Act.3

RECOMMENDATIONSThe writer is of the opinion that the Rulesof Conduct of the Code of ProfessionalConduct9be amended to read:(u) Juristic person may conduct a practice(1) A private company may conduct a

practice if (i) such a company is incorporated and

registered as a private company underthe Companies Act, 1973 (Act 61 of1973), with a share capital, and itsmemorandum of association providesthat all past and present directors ofthe company shall be liable, jointly andseverally, with the debts and liabilitiesof the company contracted during theirperiods of office;AND

(2) that each registered person, in his orher personal capacity, obtain profes-sional indemnity insurance of a certainvalue, and will not be permitted topractice as a registered person withoutsuch insurance and must furnish proofthereof prior to any engineering workbeing undertaken.

ABOUT THE AUTHOR

Emil is an arbitrator, advocate of the

high court, professional civil engineer and

registered town planner. Members are

cordially invited to submit topics of interest to

Emil at [email protected]

Notes1 H S Cilliers et al, Entrepreneurial law, 2nd ed,

Butterworths.

2 The Shipping Corp of India Ltd v Eudomon Corp

Ltd 1994 (1) SA 550(A).

3 Companies Act (Act 61 of 1973), as amended.4 Close Corporation Act (Act 69 of 1984).

5 Attorneys Act (Act 53 of 1979), as amended.

6 Public Accountants and Auditors Act (Act 80

of 1991).

7 Close Corporation Act (Act 69 of 1984).

8 Engineering Professions Act (Act 46 of 2000).

9 Code of Professional Conduct in terms of sec-

tion 42(6) of the Engineering Profession Act.


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26 Civil Engineering| August 2006

THE BROAD-BASED Black EconomicEmpowerment Act (Act 53 of 2003) becamelaw in January 2004.

That Act, however, is only the skeletonfor BBBEE. The details around the imple-mentation of the Act are contained in theCodes of Good Practice as issued by theDepartment of Trade and Industry.

The last Codes of Good Practice werereleased in December 2005 and these weresubject to public comment until the end ofMarch 2006. It is expected that these codeswill be released by the DTi in August 2006.That will announce the final chapter inrespect of the exact specifications regardingbroad-based black economic empowermentimplementation.

It is imperative that organisations gettheir house in order before this date, as it iswell known what the final Codes of GoodPractice will contain. One of the antici-pated changes to the December 2005 Codesof Good Practice is the increase in thequalifying small enterprise turnover clause.The turnover figures set out in Decemberwere outdated and clearly there will be areview and increasing of those turnoverfigures. It is also believed that the employeequalification in qualifying small enterpriseswill be dropped. Most categories containedemployees below the 50-employee level andthat qualification should be excluded.

It seems logical, in respect of corporatesocial spend and enterprise development,that the final codes will provide that both

of these elements be measured in respect

of net profit after tax. Remember: these arecontributions to mainly black beneficiariesand contributions towards assisting black-owned business in respect of enterprisedevelopment.

There is a great amount of support fora phase-in period of two years. During thisinterim period organisations would have

the choice of only measuring the manage-ment and ownership elements as opposedto the full measurement across all sevenelements. The calculation will be the scoreout of those 30 points for ownership andmanagement multiplied by a factor of 1,92.This will then be recognised as your broad-based black economic empowerment scorefor the first two years (should you elect tomeasure only those two elements).

It is also anticipated that the pensionfund issue will be excluded from owner-ship. This will close the chapter on alengthy debate in respect of pension fundownership under the ownership 20 points.

Finally it would seem that the skillsdevelopment element will still exclude yourskills development levy contributions. Theskills spend and measurement of skillsdevelopment will be over and above yourcurrent 1% skills development levy.

INFO

Should you require any further explanation in

respect of the Codes of Good Practice released

in 2005, e-mail us at [email protected] or

[email protected]

Text Jonathan GoldbergCEO, Global Business Solutions

Update on broad-based black

economic empowermentOne of the anticipated

changes to the December

2005 Codes of Good

Practice is the increase

in the qualifying smallenterprise turnover clause.

The turnover figures set

out in December were

outdated and clearly

there will be a review

and increasing of those

turnover figures



THE NATIONAL Innovation Competition(NIC) is aimed at promoting a culture ofentrepreneurship through technology inno-vation among South Africas youth. It is runby the Innovation Fund of the Departmentof Science and Technology.

Students technological inventionsare required to be of commercial value asdemonstrated by submission of a detailedbusiness plan. Government has identifiedthe importance of technology innovation incontributing to the economy and the crea-

tion of wealth for the nation. The NIC in asmall way is contributing to this importantmandate by stimulating youth to thinkcreatively, innovatively.

A combination of several factors raisesthe NIC to a higher level than that of manyother competitions in this league:

It is aimed at students registered at SouthAfrican higher education institutionsThe focus is on technological innovations not just a clever designIt stimulates students to interrogate thecommercial value of their projects, asbusiness plans form the essence of theparticipation processThe prize money is phenomenal com-pared to similar local competitionsThe winning team will be considered forparticipation in a similar competition atinternational level

The competition has the added advantagethat it provides the opportunity for entriesto be resea

Documents

SAICE Civil Engineering 14(8), 2006