hazardous materials managment handbook

7/31/2019 Hazardous Materials Managment Handbook

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LEADING

PRACTICESUSTAINABLE

DEVELOPMENTPROGRA

MF

OR

THEMINING

INDUSTRY

HAZARDOUS MATERIALS

MANAGEMENT


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HAZARDOUS MATERIALSMANAGEMENT

LEADING

PRA

CTICESUSTAINABLE

DEVELOPM

ENTPROGRAMFOR

TH

EMINING

INDUSTRY

OCTOBER 2009


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ii LEADING PRACTICE SUSTAINABL E DEVELOPMENT PROGRAM FOR THE MINING INDUSTRY

Disclaimer

Leading Practice Sustainable Development Program for the Mining Industr y.

This publication has been developed by a Working Group of experts, industry, and governm ent and

nongovernment representatives. The effort of the members of the Working Group is gratefully

acknowledged.

The views and opinions expressed in this publicat ion do not necessarily reflect t hose of the Australian

Government o r t he Minister fo r Resources, Energy and Touri sm. While reasonable effor ts have been made

to ensure that the contents of this publication are factually correct, the Commonwealth does not accept

responsibility for the accuracy or complet eness of t he contents, and shall not be liable for any loss or

damage that may be occasioned directly or indirectly through the use of, or reliance on, the contents of

this publication.

Users of thi s handbook should bear in mind that it is intended as a general reference and is not in tendedto replace the need for professional advice relevant to the particular circumstances of individual users.

Reference to companies or pr oducts in t his handbook should not be taken as Australian Government

endorsement of those companies or their products.

Cover image: Transpor ti ng hazardous substances. Source: CSBP Lim ited

Commonwealt h of Aust ralia 20 09

ISBN 978 -1-921516-47-4

This work is copyright. Apart from any use as permit ted under t he Copyright Act 196 8, no part may be

reproduced by any process without prior written permission from the Commonwealth. Requests and

inquiries concerning reproduction and rights should be addressed to the Commonwealth Copyright

Administr ation , Att orney-Generals Department, Robert Garran Offices, National Circuit, Canberra ACT260 0 or posted at w ww.ag.gov.au/cca

October 2009.


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HAZARDOUS MATERIALS MANAGEMENT ii i

CONTENTS

ACKNOWLEDGEMENTS iv

FOREWORD vii

1.0 INTRODUCTION 1

2.0 PRINCIPLES 3

2.1 Legislation and regulat ion 3

2.2 Exposure standards 5

3.0 MATERIALS OF CONCERN 7

3.1 Naturally occurr ing hazardous materials 7

Asbest iform mater ials in minerals 9

3.2 Hazardous substances 15

CASE STUDY: Copper solvent extract ion fires 20

3.3 Dangerous goods 22

3.4 Mining wastes and by-product s 25

CASE STUDY: Management of arsenic minerals

at the Yerranderie mine site 27

3.5 Securi ty risk substances 29

Consider chemicals a secur ity r isk 30

4.0 RISK MANAGEMENT 33

4.1 Worker hazard awareness 33

4.2 Communit y awareness 40

CASE STUDY: Tenby10 Program, Nyrstar Port Pir ie Smelter 41

4.3 Cont rols 42

CASE STUDY: The cont rol of pneumoconiosisin the New Sout h Wales coal indust ry 43

4.4 Suppliers 51

CASE STUDY: Amm onium nit rate t ranspor t 53

4.5 Environment 57

5.0 PERFORMANCE MANAGEMENT 59

5.1 Health and environment al monitor ing 59

5.2 Auditing 64

GLOSSARY AND ABBREVIATIONS LIST 67

REFERENCES AND FURTHER READING 73


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iv LEADING PRACTICE SUSTAINABLE DEVELOPMENT PROGRAM FOR THE MINING INDUSTRY

ACKNOWLEDGEMENTSThe Leading Pract ice Sustainable Development Program is managed by a steering

commit tee chaired by t he Australian Government Depart ment of Resources, Energyand Tour ism. The 14 themes in the program were developed by wor king groups of

government , indust ry, research, academic and communit y representat ives. Theleading pract ice handbooks could not have been completed wit hout the cooperation

and act ive part icipation of all members of t he working groups, and their employerswho agreed to make their t ime and expert ise available to t he program. Part icular

thanks go to t he following people and organisations who contr ibuted to the

Hazardous materials managementhandbook.

Professor Ian RaeChair Wor king Group

[email protected]

Mr Peter Scott

Principal AuthorPrincipal EnvironmentalGeochemist

AECOM Environment

www.aecom.com

Shelby Schofield and

Jenny ScougallSecretariat

Sustainable MiningDepart ment of Resources,

Energy and Tour ism

www.ret.gov.au

Mr Ross McFar land

National Pract ice LeaderAECOM Environment

www.aecom.com

Mr Roger Schulz

Environment al Consultant &Auditor

[email protected]


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HAZARDOUS MATERIALS MANAGEMENT v

Dr Sharann J ohnsonOccupational Health and

Safety Consultant

[email protected]

Associate Professor Brian

DaviesSchool of Health SciencesUniversity of Wollongong

www.uow.edu.au

Mr Philip MulveyManaging Director

Environmental EarthSciences

www.environmentalearthsciences.com

Mr Geoff Mance

Environmental ConsultantKMH Environmental Pty Lt d

www.kmh.com.au

Mr J on Panic

Environmental ConsultantKMH Environmental Pty Lt d

www.kmh.com.au


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HAZARDOUS MATERIALS MANAGEMENT vi i

FOREWORD

A strong commitment to leading practice sustainable development is crit ical for a

mining company to first gain and t hen maintain its social licence to operate.

The handbooks in t he Leading Practice Sustainable Development Program for theMining Indust ry series integrate environment al, economic and social aspects through

all phases of mineral product ion from exploration to construction , to operat ionand finally mine site closure. The concept of leading practice is simply the best way

of doing t hings for a given site. Leading practice is as much about approach and

att itude as it is about a fixed set of practices or a par t icular technology.The International Council on Mining and Metals (ICMM) defines sustainabledevelopment as investment s that are technically appropr iate; environment ally

sound; financially profitab le; and socially responsible. Endur ing value: the Australianminerals indust ry framework for sustainable developmentprovides guidance foroperational-level implementat ion of t he ICMM principles and elements by theAustralian mining indust ry.

A wide range of organisations have helped develop t his handbook, which will assistall sectors of t he mining industr y to reduce the impacts of minerals product ion on

the community and the environment by following the principles of leading practicesustainable development .

The Hon Mart in Ferguson AM MP

Minister for Resources and Energy, Minister for Tour ism


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HAZARDOUS MATERIALS MANAGEMENT 1

1.0 INTRODUCTIONHazardous Materials Management is one of 14 themes in t he Leading PracticeSustainable Development Program fo r t he Mining Indust ry. The program aims to

identif y t he key issues affect ing sustainable development in the mining industr yand to provide infor mat ion supplemented by case studies that ident ify sustainable

approaches for t he mining indust ry.

Leading practice sustainable development management is an evolving discipline.

As new problems emerge and new solut ions are developed, or better solut ionsare devised for existing problems, it is impor tant that leading practice be flexible

in developing solutions t hat m atch site-specific requirements. Alt hough there areunderpinning pr inciples, leading practice is as much an approach and an att itude

as a fixed set of practices or a par t icular t echnology. This handbook builds on andcomplements t he management principles and practices developed in t he Best

Practice Environmental Management Series handbook on hazardous materialsmanagement, storage and disposal.

The primary audience for the handbook are the mine, exploration and m ineralprocessing staf f who w ill come into contact wit h hazardous mater ials th rough t heir

work activit y: health and safety and emergency response staff, mine planners andmineral processing designers. In addition, people wit h an int erest in leading practice

in the mining industr y will find t his handbook relevant, including mining companydirectors, managers, communit y relat ions practit ioners, environment al officers,

mining consultant s, suppliers to t he mining industr y, government s, regulator s, non-government organisations, mining communit ies, neighbouring communit ies, and

students. It has been wr itt en to encourage t hose people to play a crit ical role incontinuously improving the mining industrys sustainable development per for mance.

The handbook has been const ructed in fou r m ain sections:

Principles contains definit ions and ident ifies sources ofrelevant Australian handling and storage legislat ion.

Mat erials of concern discusses naturally occurr ing hazardoussubstances that may be encountered dur ing mining, materials import ed

to the site (such as processing chemicals), and substances and miningwastes that are generated dur ing mining and processing.

Risk management presents risk management strategies thatmay be implemented at corporate or m ine site level, includingthe use of material safety data contained in Material Safety Data

Sheets (MSDS) and personal protective equipment (PPE).

Performance management presents information about techniques,such as monitoring, reporting and auditing, that provide inform ation

about the use of and exposure t o hazardous substances.


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2 LEADING PRACTICE SUSTAINABLE DEVELOPMENT PROGRAM FOR THE MINING INDUSTRY

References and fur t her reading contains a list of references and resourcedocuments used to compile t his handbook.

There are 14 handbooks in t his ser ies. Some discuss the management of hazardous

substances, including: Tailings management

Cyanide management

Managing acid and metalliferous drainage.

The following handbooks deal with general pr inciples of handling and managing

hazardous mater ials:

Mine closure

Materials stewardship

Evaluating perfor mance: monit or ing and auditing

Airborne contaminants, noise and vibration

Water management

Risk assessment and management.

This handbook has been designed to ident ify guiding pr inciples and leading practicesin the handling and storage of hazardous mater ials through t he mine life cycle.

It pr ovides links to relevant source mater ial and stat e and federal legislation andguidelines for fur ther reading and detail.

While a primary consideration of hazardous mater ials management is worker healthand safety, the handbook recognises the potent ial for impacts from hazardous

mater ials used and exposed during mining and mineral processing on t he naturalenvironment and the need to manage them to minim ise those impacts. The

environment al impacts from such mater ials are also discussed in the other leadingpractice handbooks listed above.


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2.0 PRINCIPLESPurposeThis section presents the regulatory regime and t he principles on which t heidentification and management of hazardous mater ials are based.

Key messages Indust rial chemicals manufactured in or impor ted into Australia

are assessed by an Aust ralian Government agency under the

Industrial Chemicals (Notification and Assessment ) Act 198 9.

Hazardous substances are governed by t wo key ty pes of legislat ion(the National Model Regulations for the Cont rol of WorkplaceHazardous Substances and the Australian Dangerous Goods

Code), but compliance is a mat ter for states and ter rit ories.

Not all hazardous substances encountered in the miningindustr y are classified as dangerous goods.

Exposure standards have been established for worksites, including m inesites, to reduce risks for people working wit h hazardous substances.

Health surveillance, as either biological monitor ing or regularrout ine medical examinations, is regulated at the state levelto protect the health of workers at some mine sites.

2.1 Legislat ion and regulat ionThis section summarises the national and stat e legislat ion controlling impor t ing,supply, storage, handling and disposal of indust r ial chemicals.

2.1.1 Chemical import s

Where a mining company plans to impor t directly chemicals for use at their site,rather t han use an Australian supplier, it must comply wit h NICNAS (the National

Indust rial Chemicals Notification and Assessment Scheme, www.nicnas.gov.au). If t hechemical or t he chemical component s in the mixture are not registered in Australia,

extensive toxicity data are required for r egist rat ion.

2.1.2 Handling and st orage legislat ion

The states and ter rit ories control the use of indust rial chemicals mainly by exercising

their extensive powers relating to pr ohibit ion, applicat ion of occupational exposurestandards, and health surveillance requirements. Many of t he controls on indust rial

chemicals focus on contr olling a chemical at a par t icular stage of it s life cycle or ina part icular situat ion. These areas include worker safety, t ransport , public health,

environment al protect ion and t he handling of hazardous substances, including theirdisposal as waste.


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The key model codes for mine sites are t hose cover ing hazardous substances anddangerous goods, which can be found on the Safe Work Australia website.1

The cent repieces are the National Model Regulations for the Cont rol of Workplace

Hazardous Substances[NOHSC:1005 (1994 )] and t he National Standard for theStorage and Handling of Workplace Dangerous Goods[NOHSC:1015(20 01)] .

Hazardous materials is an umbrella ter m used to describe any substances that ,

because of t heir chemical, physical or biological proper t ies, can cause harm topeople, proper ty or t he environment . The term collectively describes substances

according t o t he hazard t hey present, and includes dangerous goods, combustibleliquids and hazardous substances.

Legislation dealing wit h hazardous mater ials t reats them on t he one hand as

dangerous goods, or on the ot her as hazardous substances. The two categor ies areclassified according t o different criteria:

Dangerous goods are classified on t he basis of immediatephysical or chemical eff ects, such as fire, explosion, corrosion andpoisoning that might affect propert y, the environment or people.Petrol, pool chlorine and some pesticides are examples.

Hazardous substances are classified on t he basis of health effects,whether immediate or long-term, part icularly in relation t o workplaces.

For example, exposure t o hazardous substances can cause adversehealth effects such as asthma, skin rashes, allergic reactions,

allergic sensit isat ion, or cancer and other long-term diseases.

Dangerous goods are extensively regulated and controlled for t ransport by theNational Transpor t Commission, which is responsible for the Australian Dangerous

Goods Code, now in it s seventh edit ion (ADG7).2

In 200 7, the Aust ralian Government init iated changes to t he national codes at t he

federal level, and there is a plan to harmonise the framework of nat ional and statemodel codes and regulations. The new f ramework will use the Globally Harmonized

System of Classification and Labelling of Chemicals (GHS) as the basis for hazardclassification and hazard communicat ion element s on labels and MSDS.

1 ht tp:/ / www.safeworkaust ral ia.gov.au/swa/HealthSafety/OHSstandards/

2 ht tp:/ /www.ntc.gov.au/ viewpage.aspx?AreaId=35&Document Id=1147


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State and terr itor y government mining and natural resources authorit ies websitesprovide local occupat ional health and safety (OHS) and environm ental legislation:

Nort hern Terr itor y www.nt .gov.au/d/ Minerals_Energy/

Queensland www.dme.qld.gov.au/Western Aust ralia www.dmp.wa.gov.au/

New South Wales www.dpi .nsw.gov.au/

Sout h Aust ralia www.safewor k.sa.gov.au/

Tasmania Depart ment Primary Industr ies, Parks, Water andEnvironment, Tasmania www.dpiwe.tas.gov.au

Mineral Resources Tasmania (MRT)

www.mrt.tas.gov.au

Workplace Standards Tasmania

www.wst.tas.gov.auVictoria www.worksafe.vic.gov.au

Inform ation papers prepared by various stat e government agencies provideadditional informat ion on legislat ion; for example:

Information Paper No. 9, Hazardous materials legislation in Queensland:a guide developed by t he Chemical Hazards and EmergencyManagement (CHEM) Services with the assistance of the Inter-Departmental Hazardous Substances Co-ordinating Committee.

2.1.3 Workplace exposures and healt h surveil lance

The Nat ional Exposure Standards cont rol exposures to many of the hazardoussubstances used in the mining industr y known t o have acute health effect s.

State author ities also impose regulated health examinations for mining occupationsconsidered t o be high r isk. For example, in NSW, coal miners are required to undergo

a full m edical examinat ion every five years. In addit ion, Safe Work Aust ralia hasexamined health surveillance (such as biological monitor ing for lead exposure

dur ing lead mining) and established biological exposure standards in t he HazardousSubstances Infor mat ion System.

2.2 Exposure standardsOccupat ional exposure standards are developed by Safe Work Australia andregulated t hrough stat e legislation. The standards refer to airbor ne levels of

hazardous substances, including dust and crystalline silica generated in the miningprocess. It is believed that nearly all workers can be repeatedly exposed t o such

levels for a wor king life wit hout adverse health eff ects. In Australia, the levels arerefer red to in t he National Exposure Standard and are listed in t he Hazardous

Substances Infor mat ion System.3

More informat ion on exposure standards can be found in Section 5

(Performance management).

3 htt p:// www.safeworkaustralia.gov.au/swa/HealthSafety/ HazardousSubstances/HSIS


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8 LEADING PRACTICE SUSTAINABL E DEVELOPMENT PROGRAM FOR THE MINING INDUSTRY

Amphibole, and to a lesser extent serpent ine, minerals are widely dist ribut ed in theEarths crust, so asbestos can occur as an accessory mineral. These minerals arefound in mafic and ultr amafic rocks, skarn deposit s and associated igneous rocks

in contact wit h limestone, such as porphyry copper deposits. They are commonlyassociated w ith faults and shears in these rocks and geological sett ings. Asbestos

can occur as an accessory m ineral wit h ot her industr ial minerals (such as amphiboleasbestos wit h verm iculite and t alc). Fibrous minerals may be associated wit h

carbonate-facies iron formations.

Serpent ine and amphibole that are found in mafic and ultramafic rock form ationscan have fibrous and non-fibrous structur es. The fibrous for m is called asbestos

and is rare compared to ot her asbest ifor m minerals and non-asbestifor m amphiboleminerals. It is import ant t o note t hat non-fibrous for ms can have similar chemical

composition, but do not have the same health eff ects as the fibrous for ms. Someother m inerals are similar t o asbestos in their par t icle shape, but do not possess thecharacteristics required to classify t hem as asbestos.

Serpent ine and amphibole minerals are found in mafic and ultramafic rocks of t he

greenstone belts in Wester n Australia that host major nickel and gold deposits,as well as other mafic and ultramafic rocks elsewhere in Aust ralia. Rarely, these

minerals are asbestif orm and, if t hey are present, they usually occur in veins or smallveinlets. Such occurrences are usually small and isolated and are t herefore not oft en

not iced. The best known asbestos deposits are near Witt enoom in the Pilbara regionof Wester n Australia and at Woodsreef near Armidale in New South Wales.

Where asbestifor m minerals are encountered, airbor ne asbestos fibres may appear

as a minor/ t race contaminant in the dust produced during blast ing, crushing andsubsequent handling and processing. Concern about the effect on health f rom long-ter m, low-level exposure to asbestos requires that appropr iate procedures be applied

wherever asbest ifor m m inerals are encountered, to ensure that exposures are as lowas is reasonably pract icable. It is the responsibility of the mine operator to ensure

that mining operations provide a safe and healthy work environment.

Safe Work Australia defines a respirable asbestos fibre as one with a diameter less

than 3 microns (1micron = 1/ 1000 m illimetr e), a length greater t han five micronsand a length-t o-width rat io greater than 3:1. For comparison, a human hair is

approximately 20 to 100 microns wide.

With asbestos, the size of t he part icle is crit ical in determ ining whether t here will bea risk to health f rom inhaling the fibres. Fibres around 10 microns or less long and

3 microns or less wide are the most likely t o remain in t he lungs. Fibres larger t hanthis tend to be removed by the normal clearing mechanism of the lungs.


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Asbest iform mat erials in minerals

Expert guidance and a robust management program are needed whereverasbest ifor m m inerals are encountered, to ensure that exposures are as low

as is reasonably practicable. Asbestos is a known carcinogen and is regardedwit h zero tolerance by workers, regulator s and the commun ity. It is a banned

substance in many count ries.

Issues to be considered in min ing operat ions and expor ted mater ials are asfollows:

Product liability

affected by international and national laws

communit y, consumer and end user issues

cradle-to-grave documentat ion of risks and exposures.

Sustainable development

potent ial impacts on the community where waste, tailings

and mater ials are stor ed and t ransport ed (includingenvironment al and product liability r isks)

contaminat ion of widespread areas, requiring clean up.

Occupat ional health and safety r isks to workforce

industr ial relat ions impacts (asbestos has caused mor e disputes

in the wor k environm ent t han other hazardous substances)

litigation by workers

increased costs for detailed medical surveillanceand occupational exposure monit or ing.

To minimise the potential r isks from asbest ifor m material, a competent person(such as a geologist or mineralogist) should analyse exposed rock dur ing t he init ial

studies into the ore body to determine the presence and extent of asbestos.

An asbestos management plan can t hen be developed for the risk areas

determ ined through asbestos exposure monito ring. The plan should address thefollowing key areas:

Information, instruction, training and supervisionshould be provided t o all employees.

Writ ten procedures should be developed.

Airborne fibre levels should be monitored.

Regular surveillance of all mined rock should be undert akento ensure minimal distur bance of fibrous material.

(continued)


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SilicaSilica minerals make up the mat rix or occur in association w ith t he targeted mineral

in ore bodies. They include quartz, a common gangue m ineral and a const ituentin many m inerals in igneous and metamorphic rocks. Silica minerals are oft en

concent rated by t he same natural process that results in sulfide ore bodies. They arestable unt il ground or blasted into a dust.

Crystalline silica dust is classified as a Group 1carcinogen by the Inter nationalAgency for Research on Cancer.4 Hence, the National Exposure Standard is low at

0.1mg/m3. The dust is also an irr itant to t he lungs.Management of silica minerals is discussed in m ore det ail in Hustr ulid (198 2), Karm is(2001), Hedges & Djukic (2008), and Hedges et al. (200 7, 200 8ab).

Acid and metall iferous drainageAcid and metalliferous drainage (AMD) can occur naturally when rocks containing

metal sulfide minerals are exposed to oxygen and water, or when sulfidic rockmater ial is distu rbed and exposed to oxidation as a result of mining, highway

const ruction or coastal land development (acid sulfate soils). The predominant acid-

generating sulfide mineral is pyr ite (FeS2); other acid-generating m inerals includepyr rhot ite (FeS), marcasite (FeS

2), chalcopyrite (CuFeS

2) and arsenopyr ite (FeAsS).

The reaction of pyr ite wit h oxygen and water produces a solut ion of fer rous sulfate and

sulfur ic acid. Ferrous iron can be oxidised, producing addit ional acidity. Iron and sulfuroxidising bacter ia are known to catalyse these reactions at low pH, thereby increasing

the rate of react ion by several orders of magnitude (Nordst rom & Southam 199 7).

4 http://monographs.iarc.fr/ENG/Monographs/vol68/index.php

Access to all areas containing fibres should bestrictly controlled and monitored.

To t he extent that is reasonably pract icable, dust should be suppressedat source and workers should be isolated f rom dust by t he provision ofappropr iate equipment and facilities. Dust containment, collect ion and

handling facilities should be introduced to minim ise airborne fibre levels.

Approved disposal procedures should be implemented for fibrous waste.

The Wester n Australian Depart ment of Mines and Pet roleum has developed

comprehensive reference sources on asbestiform materials (www.dmp.wa.gov.au/ 6751.aspx).

Sources: Western Australian Depart ment of Mines and Petro leum and Mr A Roger, OH&S Pty Ltd.


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In undisturbed natu ral condit ions, acid generation is a relatively slow process overgeological t ime. Mining and processing of r ocks and materials containing m etalsulfide substances greatly enhances the acid-generating process because it rapidly

exposes those substances to oxid ising condit ions.

Not all sulfide minerals are acid-generating dur ing oxidation, but most have thecapacity to release metals on exposure t o acidic water. During mining, reactive

sulfides can be rou t inely exposed to air and water in waste rock piles, ore stockpiles,tailings storage facilities, pits, underground mines, and heap and dump leach piles.

Leading practice AMD management involves st rategies to minim ise the interact ionbetween reactive sulfides and air, water or bot h (DITR 2007). Because large masses

of sulfide minerals are exposed quickly during m ining and milling, the surroundingenvironment often cannot attenuate t he resulting low pH conditions.

Metals found in water draining f rom m ine sites include Ag, Al, As, Ba, Be, Cd, Co, Cr,

Cs, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Ra, Sb, Se, Sr, Th, Tl, U, V and Zn. Metal concentrationsincrease in waters at lower pH. Once released, metals will persist in t he environment .Their concent rat ion in water can be reduced th rough physical removal (sorpt ion,

precipitat ion, biological uptake) (Smit h 200 7).

Metals increase the t oxicity of mine drainage (Earle & Callaghan 199 8 ) and act as

metabolic poisons. Iron, aluminium, and manganese are t he most common heavymetals compounding t he adverse effects of m ine drainage. Heavy metals are

generally less tox ic at cir cum-neut ral pH. Trace metals, such as zinc, cadmium, andcopper, which may also be present in mine drainage, are toxic at extremely low

concent rat ions and may act synergist ically to suppress algal growt h and affect

fish and benthos (Hoehn & Sizemore 1977). In addit ion to dissolved met als, iron oraluminium hydroxide precipitat e may form in streams receiving mine discharges wit helevated metals concent rat ions. Ferr ic and aluminium hydroxides decrease oxygen

availability as they for m; the precipitate may coat gills and body surfaces, smot hereggs, and cover t he st ream bot tom , filling in crevices in rocks, and making t he

subst rate unstable and unfit f or habit ation by benthic organisms (Hoehn & Sizemore1977).

Aluminium rarely occurs naturally in water at concentrat ions greater t han a fewtent hs of a milligram per litr e; however, higher concent rat ions can occur in acidic

drainage from m ine sites as a result of the breakdown of clays (Hem 1970 ). The

chemistry of alumin ium compounds in water is complex. It combines with organicand inorganic ions and can be present in several for ms. Aluminium is least solubleat a pH between 5.7 and 6 .2; above and below t hat range, it tends to be in solution

(Hem 1970, Brown & Sadler 198 9). Once acid drainage is created, metals are releasedinto t he surrounding environment , and become readily available to biological

organisms. Historically, AMD, characterised by acidic metalliferous conditions inwater, is responsible for physical, chemical and biological degradation of stream

habitat in many areas of t he world where mining has occurred.


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While the main im pact of AMD is on environmental values, in extreme cases it canpotent ially affect human health through contaminat ion of water supplies and heavymetal t ake-up in aquatic organisms used as food. Managing acid and metalliferousdrainage(DITR 2007) details the underlying geochemistr y and the impacts of poor lymanaged drainage, and includes case studies of best practice management.

Acid drainage affect ed King River, Tasmania, downstream from

Mount Lyall Copper Mine. Source: Professor David J Will iams.

React ive clays and salini t y

In many par ts of Australia, mining is associated wit h salinity. Salinity is a result of twoseparate occurrences: aeolian deposition of salt fr om the sea, including salt basins

being deposited and leached into t he regolith, over t he past two million years; andconnate salts laid down wit h t he ore body. In both cases, salt-laden overburden is

deposited wit h t he waste rock in overburden or waste rock dumps. Leaching of saltfr om t he overburden and disposal of salt-enr iched groundwater can be the greatest

regional impact f rom mining. Many sedimentary basins, including the Hunter Valleyand the Bowen Basin, contain connate water that is salty. Salty water (star t ing above

about 10% of seawaters salt concentrat ion) has an osmot ic potent ial too high forfreshwater biot a and most terrest rial plants to survive. Therefore, it does not take

much salt to destroy a ripar ian environment. Victor ious arm ies sometimes ploughedsalt int o the farmland of enemies to render it useless. They were successfu lthatland remains unusable today. Careful management of waste r ock, overburden and

groundwater discharges is required to ensure that t he environm ental impacts ofsalinity are avoided.


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Alt hough saline groundwater is enriched in sulfate, discharges of saline waterinto dams or ephemeral st reams might have no apparent short -term im pacts.However, in the presence of organic matt er under aerobic condit ions, the sulfate is

converted to monosulfide black ooze that collects at the bot tom of t he water bodyor as amorphous pyrite in water logged soil. A drop in water level due to a climate

change or change in process may expose the ooze, which can be oxidised and rapidlyproduce sulfur ic acid, causing plant and fish kills.

React ive clays and sodicit y

Although at first sight clay minerals do not appear to be hazardous, the physicalchanges in their structu re brought about by exposure to cert ain chemicals can

damage mineral processing equipment and the environment. The primary m ineralsconcerned include kaolinite and benton ite, while secondary m inerals such as

smectite and illite may result fr om weather ing. Clay minerals have an excess of

negative charge across the crystal, which is balanced by cations f rom the pore water.Because of the mineral structure, clay minerals clump together into dom ains wit hcations between the clay sheets within t he domain and in a cloud around t he domain.

Cert ain clay mineral clumps swell and disperse (break up) or clump t ighter toget her(coagulate) depending on cations in t he surrounding por e water. These minerals

include clays of t he mont mor illonite group (smectit e, bentonit e, high-chargedvermiculit e) and illite and interstratified minerals. The type, molar st rengt h and tot al

ionic activit y of cations in solution aff ects these swelling clays, causing swelling andcoagulat ion depending on the chemical stat e. The cat ions can swap wit h each other,

depending on t heir valency and ionic st rengt h, and are known as exchangeable

cations.In the nat ive stat e, the exchangeable cations consist of calcium, sodium andmagnesium. When t he exchangeable sodium content (relative to t he cation exchange

capacity) exceeds 4% in the presence of swelling clays, the domains will disperse,leading to high sediment, piping erosion and poor retur ns of water and reagents from

tailing dams. The inverse also happens to clays prone t o swelling. The introduct ion ofsaline water, acid water, or water r ich in ammonium, divalent and t rivalent cations will

cause swelling clay domains to excessively coagulate to t he part icle-size equivalentof silt or fine sand. This can cause natural clay liners or impor ted bentonite liners to

leak. The potential for leaching water int o the clay to do t his is defined as sodium

adsorpt ion rat io for mine waters (SAR-Mining). This needs to be interpreted bysomeone with exper t ise in clay minerals.

Failure to consider t he occurrence of t hese clay minerals can have a substantial

impact on recoverable efficiencies, problems wit h piping failure, high sedimentload in dams, creeks and ponds, and, in the worst case, catast rophic ear then dam

failure. It can also result in dam liners leaking at a rat e up to 100 0 t imes greater t hanexpected.


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RadioactivityAll minerals contain radionuclides that are members of t he naturally occurr ingradioactive decay chains. The impact of these radionuclides needs to be considered

in certain types of mining. Igneous and certain metamor phic rocks are moreradioactive t han most sedimentary rocks. Thus living in Arm idale you will be exposed

to elevated background radioactivit y compared t o living in Sydney. This radioactivityobviously increases in uran ium orebodies, but can also be elevated in mineral sands,

rock phosphate and other ores.

Exposure to elevated radioact ivity levels can also occur dur ing rare eart h product ion,bauxite production , and oil and gas extraction, amongst many examples. The level of

potent ial hazard from radioactive minerals depends on the type of radioactivit y andits half-life. One of t he major radiological risks in mining is associated wit h inhalation

of radon (a radioactive gas with a shor t half-life) and its shor t-lived radioactive decayproduct s. Radon is produced by t he radioactive decay of radium. Radon can be amajor problem in underground mines and needs to be carefully considered.

There are a number of laws covering radioactivit y. You should contact the

radioactivit y liaison officer in your state depart ment of mines for more informat ion,or refer to the Code of Practice and Safety Guide for Radiation Protection andRadioactive Waste Management in Mining and Mineral Processing (2005) onthe website of the Australian Radiation Protection and Nuclear Safety Agency

(ARPANSA).5

Met haneMethane is commonly encountered in coal seams and is a well-known explosive

hazard. Adequate vent ilat ion can min imise the risk. In some cases the coal seammethane is collected for use as fuel.

3.1.3 Managing naturally occurr ing hazardous mat erials

Management of naturally occurr ing hazardous materials begins wit h their cor rectidentification dur ing pre-feasibility planning, followed by proper characterisation of

the orebody, waste rock, overburden, mine process residues and natural soil underthe mine infrastructur e. If problematic naturally occurr ing minerals are encountereddur ing mining, activit ies should cease unt il t he hazard has been proper ly evaluated

and correct ive act ion has been planned.

Proper characterisation and hazard assessment will involve the use of anexperienced environment al geochemist or soil chemist and occupat ional hygienists.

These professionals should be involved during the planning stage to prepare amitigation or avoidance program or corrective action.

Hazards from nat urally occurr ing substances depend not only on t he concentrat ionof t he substances but also on their chemical for m and the surrounding environment .

A risk assessment is undert aken to deter mine whether t he natural geology andenvironment can cont inue to accommodate t he substances wit hout causing an

adverse impact on human health or the environment . This is done by confirming

5 htt p:// www.arpansa.gov.au/pubs/r ps/rps9.pdf


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t he concentrat ions of t he substances and comparing those concent rat ions withpublished crit eria or threshold levels that are likely to cause harm t o human healthor the environment . However, threshold levels and published criter ia are oft en

guidelines, and site-specific levels are often more suitable because of var iations ingeological and environment al conditions.

For example, react ive clays are not dispersive unt il sodium is added at low

concent rat ions. Adverse reactions wit h reactive clays are more common in thegold industr y in eastern Australia, where sodium hydroxide is used to elevate pH to

control cyanide, than in the goldfields regions of Wester n Aust ralia. This is becausealthough the sodium content is high, the sodium is present in sodium chloride, so

the salinity is very high and the clay is so weathered t hat m inimal reactive claysoccur. In some cases, it is bett er t o use anot her caustic agent bot h for environment al

protection and for gold recovery because the sodium promot es dispersion, whichincreases the potent ial for failures in tailings dam str uctur es and leaks intowaterways.

Work practices and procedures for a safe and environmentally acceptable mine site

start well before any mining commences, and are ideally developed dur ing detailedor bankable feasibility study stages. These practices are designed to mit igate t he r isk

to t he environment and worker health during constr uction and operation of the mineand associated facilities, and should demonstrate cont inued improvement over t ime

in accordance with changes in relevant legislation, standards and guidelines.

Typically, an environment al geochemist and occupational hygienist or similar

suitably qualified professional should be involved in t he identification of pot entially

hazardous naturally occurr ing substances, and in the design of waste emplacementfacilities to mit igate the potent ial environment al impact f rom t hose substances.

3.2 Hazardous substancesTo understand t he workplace health and safety requirements for hazardous

mater ials, legal obligat ions must be considered and r elevant legislation and codes ofpractice must be understood.

3.2 .1 What law applies?

State legislat ion, codes of practice and guidance documents must be considered. The

regulator y regime is not the same in all stat es. Details can be obtained through thewebsites of state m ines depart ment s or workplace author ities (listed in Section 2.1.2).


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3.2 .2 What are hazardous substances?

Hazardous substances are mater ials that can have an adverse effect on hum an

health due to their physical, chemical, and biological proper t ies. A chemical

or mixt ure of chemicals is classified as a hazardous substance if it meets t hetoxicological crit eria in the Approved crit eria f or classifying hazardous substances[NOHSC: 1008(2004)] , which addresses short -term and long-term health eff ects.More infor mat ion about hazardous substances can be found on t he Safe Work

Australia website.6

Under t he National Model Regulations for the Cont rol of Workplace HazardousSubstances [NOHSC:1005 (1994)], a hazardous substance is one that :

is included on the List of Designated Hazardous Substances [or]

has been classified as a hazardous substance by the manufacturer or impor ter

in accordance wit h the Approved crit eria f or classifying hazardous substances.If hazardous substances are not stored or handled correct ly, they harm workers,members of t he public, proper ty and the environment. Detailed requirements

are out lined in stat e hazardous substances legislation fo r labell ing, MSDS, r iskassessments, control strategies, training and health surveillance of workers.

Hazardous mater ials include many commonly f ound industr ial, commercial,pharmaceut ical, agricultural and domestic chemicals, many of which are found in

mine sites, as well as dusts, metal f umes and met al concent rates. Examples are

flotation chemicals, solvents, cleaning agents, petroleum products, compressed

gases, and biocides.

Some chemicals and propr ietary m ixtur es are hazardous substances, includingmany dangerous goods for which a manufacturer or import er m ust prepare, amend,

provide and review an MSDS. All MSDS for industr ial product s introduced on sitewill have a statement (Classified as a Hazardous Substance or Not Classified as a

Hazardous Substance) that alert s the user t o apply appropriat e engineering cont rolsto prot ect workers.

Hazardous substances classifications are:

Very Toxic

Toxic (includes acute toxic chemicals; carcinogens, categor ies 1and 2; mut agenicagents, categor ies 1and 2; and reproduct ive toxic agents, categor ies 1and 2)

Harmful (includes carcinogens, category 3; mutagenic agents,category 3; reproduct ive toxic agents, category 3)

Corrosive

Irritant

Sensitiser.

6 htt p:// www.safeworkaustralia.gov.au/swa/HealthSafety/ HazardousSubstances/


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Each hazardous substance MSDS will include a series of r isk and safety phrases toassist the worker to handle it safely and be aware of the hazards. The Safe WorkAustralia website includes infor mat ion on hazard substance labelling.7

Many hazardous substances are also classified as dangerous goods, but chemicalswit h long-term health ef fects (such as carcinogens and sensitisers) are not classifiedas Class 6 Toxic and Infectious Substances under the Aust ralian Dangerous Goods

Code (ADG7).

In the next few years, it is intended to in tr oduce the Globally Harmonised System

of Classificat ion and Labelling of Chemicals (GHS). Developed by a United Nationsagency, the GHS provides a uniform way of classifying chemicals internationally. It

also uses risk statement s and pictograms to inform chemical users about chemicalhazards they may be exposed to. The GHS system will have impact s on the curr ent

system of classification and labelling of hazardous substances, and sites should

review t he final program when it becomes available.

Bulk storage vessels should be appropr iately labelled or placarded in accordance wit hADG7. Hazardous substances that are not dangerous goods should be appropriately

identified. The MSDS should be located nearby in a storage container (as discussed inSect ion 4.1.2).

A full list ing of hazchem and dangerous goods placarding requirements can be found

in ADG7.

Hazardous substances used and hazardous waste generated on mine and mineral

processing sites can include t he following:

Acids (sulfuric, hydrochloric). Contact wit h strong acid liquids or fum es isa human health hazard and may also cause st ruct ural damage in a facility.

Releases of acid to t he environment may have direct eff ects on biota butalso solubil ise and t hus mobil ise heavy met al toxicant s, as described inthe Managing acid and metalliferous drainagehandbook (DITR 2007).

Sodium cyanide for gold r ecovery in large operat ions. Cyanide management(DRET 2008a) provides extensive inform ation about sodium and calciumcyanides, wit h part icular attention t o toxicity in mammals and environment al

impacts. Environmental best practice is exemplified by adherence to t he

International Cyanide Management Code for the Gold Mining Indust ry, towhich major gold mining organisations subscribe.8 The code covers theproduct ion, transport , use and disposal of cyanides. The risk of cyanide

poisoning arises from ingestion and exposure t o wor kplace vapours, mistsand solutions. Small quant it ies of hydrogen cyanide are generated when

sodium cyanide is exposed to moist air, and for genet ic reasons onlyone person in two is able to detect t he odour of hydrogen cyanide.

7 ht tp:/ / www.safeworkaustralia.gov.au/swa/HealthSafety/ HazardousSubstances/Labelling/

8 http://www.cyanidecode.org/


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Mercury for gold recovery in small/art isanal operations. In small or art isanaloperations, workplace concentrations of mercur y should be monit oredrout inely where exposure is possible, for example from t hermal desorpt ion

of metallic mercury. This can occur when ores containing t race amount s ofmercur y (some zinc concent rates, for example) are roasted. Risk assessmentand management(DRET 2008b) includes a case study of the reduct ionof mercury pollut ion fr om ar t isanal mining. In that case, assistance from

a mining company operating nearby was provided under the UnitedNations Industr ial Development Organizations Global Mercury Project.

Metals as ions or complexes from Cu, Pb, Zn, Ni, Fe, As, Hg and Cd sludges orsolutions. Recovery of the metal is usually the object of the mining project ,but hazards may arise from t he presence of toxic by-products (for example,

arsenic and cadmium) or metals released as a result of developing acidification,as descr ibed in Managing acid and metalliferous drainage(DITR 20 07).

Thiosulfates and polyt hionates, also result ing f rom acid mine wateror processing solut ions. Sodium dit hionite generates sulfur dioxidein solution and may be stored on mine sites as an alternat ive togaseous sulfur dioxide. Accidental wett ing of dit hionite leads to an

exotherm ic process that may produce sulfur dioxide fumes.

Process reagents (acids, alkalis, frot hers and collectors, modifiers,flocculants and coagulants) t hat contain aluminium and iron saltsand organic polymers. Refer to t he MSDS for t hese substancesfor informat ion necessary for best practice management.

Nitrogen compounds from blasting materials. In enclosed spaces, the combustionproduct s fr om nit rate explosives (mainly ammonium nit rate and fuel oil at

present) need to be dispersed before work can restart in the affected area.Best practice consists of adequate ventilat ion and monitor ing of t he workplaceatmosphere, rather t han the use of personal prot ective equipment.

Oil and fuel used for engines, power plants, and lubrication. Althoughhydrocarbon products can cause dermatit is when skin is contacted, fire is themain hazard. Because considerable quant it ies of hydrocarbons may be stored

on a m ine site, their presence also constit utes a secur ity hazard because

they could be targeted in an att ack. There are also potential impacts on t heenvironment fr om spills, storage tank leaks and accidental discharges.

Suspended soils, mine water, surface drainage and process effluents. Stat eand terr itor y regulat ions cover discharges to watersheds and water -bodies, but best practice should go beyond mere compliance and seek

oppor tunit ies to avoid environm ental damage and to improve water quality.

Polychlorinated biphenyls (PCBs) f rom t ransformers. Australias PolychlorinatedBiphenyls Management Plan (200 3) has been taken up in stat e and terr itor yregulations.9 As a result of ear lier effor t s to remove PCBs from service,

9 http:/ /w ww.environment.gov.au/sett lement s/publications/chemicals/scheduled-waste/pcbmanagement/index.html


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many t ransform er oils are actually dilute solut ions of PCB in paraffin.Where the PCB content is 50 mg/ kg (50 ppm) or greater, the materialmust be tr eated to dest roy PCBs and reduce the level to 2 ppm or less.

Although complete phase-out may still be some years away, most PCB-containing oil has been removed f rom serv ice and t reated as required.

Asbestos from on-site plants, including asbestos cement sheets in oldbuildings. Asbestos lagging is seldom employed on pipewor k thesedays, but some old plants may st ill contain it. State and terr itor y

regulations place restr ictions on it s removal and disposal.

Surplus paints, pesticides and laboratory chemicals. Stored oil-basedpaints are fire hazards, while pesticides and laborator y chemicals mayhave human health impacts, environment al impacts, or both. Chemical

containers may contain residual chemicals that pose risks to hum an

health and the environment . They should be disposed of safely. Cleanedcontainers might not be hazardous, and collect ion and recyclingopt ions may be available under t he drum MUSTER program for plast ic

and metal containers in which pesticides have been supplied.10

Solvents used in extraction plants. Hydrocarbon solvent s, such as kerosene,are used in solvent ext raction plants for separating complexed metal ions. Asfor petroleum products, there are flammability hazards and securit y r isks.

Atm ospheric contaminants can include the following:

Dust/particulates. These can include crystalline silica, lead and n ickel.

Gases produced by combustion. These are produced by blasting and industr ialcombustion engines, and include CO, CO2, NOx, SO2 and diesel par t iculate.

Natural gas. This includes methane, which is common in coal mines but rare inbase metal mines.

Chlorofluorocarbons (CFCs) from cooling equipment andfire protectiondevices. CFCs can be released wit h equipment fails. Alt hough they arenot tox ic, CFCs released into enclosed spaces can displace air and createan asphyxiat ion hazard. Most CFCs were phased out some years ago

because they damage t he Ear ths ozone layer. They were replaced with

hydrochlorofluorocarbons (HCFCs) or hydrofluorocarbons (HFCs), which posethe same asphyxiation hazards but are also flammable. Other hazards mayemerge from t he reintroduction of sulfur dioxide and ammonia, and possibly

supercrit ical carbon dioxide, as new r efr igerants t o replace t he HCFCsbecause of HCFCs global warming potent ial. The older chemicals have the

potent ial to be risks to human health if handled incorrect ly and released.

10 htt p:// www.drum muster.com.au/


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Gross emissions to the atmosphere. Gross emissions are a special category ofhazardous mater ials. They are discussed in the leading pract ice handbook

Air contaminants, noise and vibration(DRET 2009), which covers what areknown as the cr iteria pollut ant sSO

2

, CO, NO2

, photochemical oxidants report edas ozone, lead, and par t iculate mat ter (PM10). Emissions of hydrocarbons

must be repor ted t o t he National Pollutant Inventory as volatile organiccompounds. From 1J uly 20 09, emissions of greenhouse gases such as

carbon dioxide and methane need to be report ed to t he Greenhouse andEnergy Data Officer in t he Greenhouse and Energy Report ing Office.11

11 h tt p:/ / climat echange.gov.au /repo rt ing/

CASE STUDY: Copper solventextraction firesThe first two commercial copper solvent ext raction (CuSX) plants were small-

scale plants built in Ar izona in the late 196 0s. The plants were built t o t reat heapleach and dump leach solut ions, respect ively, and to produce 550 0650 0 short

ton per annum (stpa) cathode copper. They were followed soon after by a muchlarger CuSX plant in Zambia, which treated tailings leach solution and produced

approximately 100,000 tpa cathode copper. Since then, CuSX plants haveproliferat ed world-wide. Cont inued improvement s in design and lower unit capitaland operating costs have led to t he product ion of up t o 168 ,000 tpa (185,00 0

stpa) at t he wor lds largest electrowinning (EW) plant , at Morenci, Ar izona. Aneven larger 20 0,00 0 tpa capacity plant is to be built in Chile.

In CuSX plants designed wit hin t he past two or three years, fire safety has been

closely examined and incorporated int o appropr iate low-r isk designs. However, itseems highly likely t hat fire r isks and cont rols were not adequately addressed in

plants designed before 200 2.

Small but serious CuSX fires occurred at copper heap leach operations in

Ar izona in 2003 and in Mexico in 2004. The fires demonstrated the need fora serious and immediate review of CuSX design policies for fire control. Both

were examined in detailed reviews of fire safety, but there has been only lim itedpublic report ing of the findings. The results of t hese and ot her reviews are being

applied to the design of some new plants and possibly to the retr ofit of someexist ing plants to m inimise the risk of fire. Litt le is known about refits of the

older CuSX plants, which might still face significant fire risk.

(continued)


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Causes of fires in CuSX plants include static electricity, inadequate piping design(allowing t he form ation of flammable vapours and mists inside organic drain

lines), and human error dur ing maintenance work. Of four fires since 1969, allwere in relatively new plant s. There appears to be no connection between t he

size of t he mining companies or constr ucting engineer ing companies and therisk of fires. The fires were more likely in a culture t hat has been insensitive to

the real risks of fire in CuSX plant design, operation and maintenance.

Solvent extract ion is practised at t wo Aust ralian minesRanger and Olympic

Dam. No solvent fires have been report ed at Ranger, but BHP Billitons 200 3Environment, Health and Safety Report said of the Olympic Dam site:

In October 20 01, a fire caused substant ial damage to the solventextraction unit at Olympic dam. There had been a fire in a similar area

of t he plant in December 199 9. The 2001fire was most l ikely caused byignition of solvent-soaked crud (an impur ity f rom t he solvent extract ion

process) inside a solvent t ransfer pipe. The hazard of an internal fire wasnot identified at any t ime during t he design, constr uction and operation

of t he solvent ext raction plant, and had not previously been experiencedin the solvent extraction industry.

In rebuilding the solvent extract ion plants, we incorporated new

standards for fire prevention and fire protection as identified in theinvestigation of t he 20 01fire. They include:

changing pipe work material fr om high-densitypolyethylene to conduct ive, fibre-reinforced plast ic

to reduce static build-up in the pipe work

installing an automat ic system to scutt le solventfrom t he tanks in the event of a fire

increasing t he bunding and drainage sumps tocontain and r emove any solvent spillage.

No further fires have been report ed at t he Olympic Dam facility.

Source: Olympic Dam, including mater ial fr omhsecreport.bhpbilliton.com/wmc/ 200 3/sitedata/crp_ehsprf_ftly.htm


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3.3 Dangerous goodsDangerous goods should not be confused wit h hazardous substances they areclassified according t o diff erent crit eria. Dangerous goods are classified on t he basis

of immediate physical or chemical effects, such as fire, explosion, corrosion andpoisoning affect ing proper ty, the environment or people.

3.3.1 What law applies?

Regulations and codes of practice governing t he storage and handling of dangerousgoods in the workplace can be obtained from state mines department s andwor kplace author ity websites (listed in Sect ion 2.1.2).

The Australian Dangerous Goods code (current ly in it s seventh edition, ADG7),

published by The National Transpor t Commission, covers t he t ransport of dangerousgoods.12

3.3.2 What are dangerous goods?

Dangerous goods are usually chemicals with t he potent ial to present an imm ediatethr eat to people, property or t he environment if they are not properly contained or

controlled.

3.3.3 Types of dangerous goods

Substances (including mixt ures and solutions) and art icles subject to the ADG7 are

assigned to one of nine classes according to t he hazard or t he main hazard t heypresent . The classes are denot ed by labels (or diamonds), and some are subdiv ided

into divisions.

The classes and divisions are as follows:

Class 1: Explosives

Division 1.1: Substances and ar t icles which have a mass explosion hazard

Division 1.2: Substances and ar t icles which have aprojection hazard but not a mass explosion hazard

Division 1.3: Substances and ar t icles which have a firehazard and either a minor blast hazard or a minor projection

hazard or both, but no t a mass explosion hazard

Division 1.4: Substances and ar t icles which present no significant hazard

Division 1.5: Very insensitive substances which have a mass explosion hazard

Division 1.6: Ext remely insensit ive ar t icles whichdo not have a mass explosion hazard

12 htt p:/ /www.ntc.gov.au/ viewpage.aspx?AreaId=35&Document Id=1147


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Class 2 : Gases

Division 2 .1: Flammable gases

Division 2.2: Non-flammable, non-t oxic gases

Division 2.3: Toxic gases

Class 3: Flammable liquids

Class 4 : Flammable solids; substances liable to spontaneous combustion;substances which, in contact wit h water, emit flammable gases

Division 4.1: Flammable solids, self-reactive substances

and solid desensit ised explosives

Division 4.2: Substances liable to spontaneous combustion

Division 4 .3: Substances which in contact wit h water emit flammable gases Class 5 : Oxidising substances and organic peroxides

Division 5 .1: Oxidising substances

Division 5.2: Organic peroxides

Class 6: Toxic and infect ious substances

Division 6.1: Toxic substances

Division 6.2: Infectious substances

Class 7: Radioactive material Class 8 : Corrosive substances

Class 9: Miscellaneous dangerous substances and articles

The numer ical order of the classes and divisions does not denote t he degree of danger.

Table 3.2 gives examples of dangerous goods and t he places they might be found on

a mine site.


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Table 3.2 : Dangerous goods and t heir l ikely locat ions on mine sit es

Class Descript ion Examples Locat ion in mine

1 Explosives ANFO M

2.1 Flammab le gases l iquefied petr oleum gas (LPG)liquefied nat ural gas (LNG)acetyleneoxygenmethane

PPP,WS,MPM

2.2 Non-flammable,non-toxic gases

nitrogencarbon dioxidecompressed airhelium

PP,W,MM,P,WSP

2.3 Toxic gases anhydrous ammoniahydrogen cyanidesulphur dioxidecarbon monoxide

PP, WP, WM, P, WS

3 Flammable liquids unleaded petrol (ULP)dieselkeroseneaviation fuel

M, WSMP

4.2 Substances liableto spontaneouscombustion

Pyrite bearing coalSome base metal sulfides in the presence of pyrit e

M, WM, W

5.1 Ox id ising agents Caros acidammonium nitratehydrogen peroxidepotassium permanganatecalcium hypochlorite

PM (explosives)PPP

6.1 Toxic substances cyan idearsenic compoundscadmium compounds

PP, WP, W

7 Radioactivematerial

naturally occurring radioactive m ineralscontaining radioactive elements (U, Th Ce etc.)radon gasradium in dust and watermeasuring instruments using radioactive sources

M, P, WS, W

8 Corrosivesubstances

nitr ic acidsulfuric acidhydrochloric acidCaros acid

sodium hydroxidecalcium hydroxidecalcium oxidelead acid batteries

PPPP

PPPW

9 Miscellaneousdangerous goods

asbestossome metal concentrates

W, P, M, WSP

M = mining; P = processing; W = waste; WS = workshop and maintenance

ADG7 was issued in 200 9, and included prot ocols and crit eria fo r aquatic

environment al toxicity t est ing. Those inclusions have impacts on the t ransport ofmetal concentrates off site to por ts, as there are cases where result s for diff erent

metal concentrates have been classified as Class 9, UN 30 77, EnvironmentallyHazardous Substances. (UN 3077 relates to mixt ures of solids which are not subject

to t he ADG7.)


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Mine sites must test their concentrates before t ransport to determine whetherthey are classified as Class 9, UN 3077. Classified concentrates must be storedand handled in compliance wit h AS 46 81and transpor ted in compliance with t he

requirements in ADG7.

3.4 Mining wastes and by-product s

3.4 .1 What are mining waste materials?

Mining waste mat erials are a class of materials generated through t he mining and

processing of rock mater ial containing economic quant ities of metalliferous orindustr ial minerals, coal, or oil (shale oil).

3.4.2 Types of mining waste materials

There are several classes of m ining waste. Waste rock or overburden is mater ial that

is mined from an open cast pit or underground workings in order t o gain access torock m ater ial hosting economic grades. The classification of waste is based largelyon t he market pr ice and t he grade of t he target commodit y. Generally, waste rock

contains little or no economic quant it ies of t he mineral or energy commodit y. Itincludes topsoil, weathered and part ially weathered overburden, and primary or

unweathered waste rock. Topsoil, on t he ot her hand, cannot be regarded as wastesince it is a valuable resource for rehabilitat ion of the mine site upon closure. In

many met alliferous and coal mines, low-grade or sub-economic grade ore or coalis stockpiled fo r later processing when economic circumstances improve and

commodit y pr ices rise. Oft en, low-grade ores are left to weather, are never t reatedand become classed as high-grade waste rock stockpi les. Stockpiles of low-grade

oresor high-grade waste rock, depending on t he economic viewpointof ten containsulfides that can oxidise when exposed to air and moisture, for ming sulfur ic acid.

The acid is itself hazardous, but also carr ies dissolved met als that can damage theenvironment. Managing acid and metalliferous drainage(DITR 200 7) gives a fullaccount of t he hazards and the best practice relating to t hem.

Tailings are t he fine-grained residue remaining aft er t he processing of ore and

extract ion of t he target commodit y. Tailings fr om metalliferous ores contain smallquantit ies (sub-economic grade) of t he target m etal plus accessory minerals (for

example, sulfide minerals, oft en in high concent rat ions), metal ions and process

chemicals. Processing of coal generatesfi

ne- and coarse-grained rejects, which maycontain sulphide minerals and metal ions, including aluminosilicates that may be asource of alum inium in acidic mine drainage. Tailings best pract ice is described in

Tailings m anagement (DITR 2007).

Heap leaching technology is applied to low-grade ores. The ore is crushed to a

nominal par t icle size, stacked on lined pads, and ir rigated wit h a leaching solution,such as cyanide for gold ores or sulfur ic acid for copper ores. When t he process

is complete, the heap leach pads are decommissioned and t he remnant mater ialbecomes a mine waste product. A variat ion on t he heap leach pad is the dump leach,

in which low-grade ore is placed in a stockpile and ir rigated wit h a leaching solut ion

in an operation similar to heap leaching.


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The other main waste material is mine water t hat accumulates within minestructur es, such as open pit s, underground, or interacts with mine distur bed areas.Fur ther infor mat ion on tailings can be found in t he leading practice handbooks

Tailings m anagement, Managing acid and metalliferous drainage, and Watermanagement.

Monitor ing the concentrations of hazardous mater ials discharged into tailings

storage facilit ies of any typesuch as a paddock, central discharge t ailings (CDT) orpit infillfor environmental effects is part of best practice for the mining industry. For

example, the gold mining industr y has adopted t he voluntary International CyanideManagement Code to m inimise the hazardous effect of cyanide on the environment .

All operat ions are expected to comply wit h t he code, compliance is verified byindependent audito rs, and repor ts are published on the Internat ional Cyanide

Management Inst itu tes website.13

One site, Anglo Gold Ashant i Aust ralias Sunr ise Dam operat ion, uses hypersalinegroundwater in it s gold winning process. While the operat ion works cont inuouslyto r educe the cyanide levels used in the process to min imise the loss to t he CDT,

the discharge t o t he CDT is st ill above the Int ernat ional Cyanide Management Codeguideline level of 50 mg/ L weak acid-dissociable cyanide. Recent extensive

peer-reviewed research14 provided a novel way to reduce the environm ental impactand prevent wildlife death (par t icularly bird deaths) due to cyanide toxicity by

ensuring t hat discharge to the CDT is above a cer tain m inimum in salinity. Theresearch ident ified protective mechanisms that prevent birds fr om drinking from t he

ponded solution and drains, and produce a faster oxidation rat e of t he cyanide to less

toxic cyanate for ms. Even the most salt-tolerant avian species cannot drink waterwit h a salinity above 50,00 0 mg/ L tot al dissolved solids.

Simple daily salinity deter minat ion confirm s that the cyanide solut ions are above

the minimum salinity level. When rain or storms threaten to dilute t he salinity belowthe established safe level, wind, solar and mine-operated groundwater pumps

add hypersaline groundwater to t he cyanide solut ions, thus protect ing wildlife andcontinuing t he fast oxidat ion of t he cyanide.

The Cowal gold mine in central New Sout h Wales is a heavily regulated operat ionbecause it is in an environment ally sensitive area adjacent to a lake that fills

intermittently fr om overflow of the Lachlan River. The concent rat ion of weak

acid-dissociable cyanide discharged t o t ailings ponds must not exceed 30 ppm andmust remain below 20 ppm for 90 % of operating time, in order to reduce the hazardposed to birdlif e in the area.

13 ht tp:/ /www.cyanidecode.org/

14 ACMER research pro ject 58 : A Risk Assessment of the Eff ects of Goldm ining Cyanide-Bear ingTailings Solutions on Wildlife.


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CASE STUDY: Management of arsenic

minerals at t he Yerranderie mine sit eYerrander ie is a histor ic abandoned silverlead mining town southwest of Sydneynear t he Wor ld Herit age listed Blue Mountains Nat ional Park. The site is about12 kilometres upst ream f rom Sydneys major water supply dam, Warragamba.

Mining at Yerrander ie occurred between 189 8 and t he 1930 s, and recoveredsignificant quant ities of silver, lead and gold. There was minimal rehabilitat ion

aft er m ining ceased.

In 200 3, intensive environm ental studies found t hat small areas of t he site had

arsenic contaminat ion levels that were potentially hazardous to hum an healthand the surrounding environment , in part icular Warragamba Dam. At some

locations, the material contained up t o 25% arsenic. Fencing and signage aroundthose areas was a temporar y solution to protect the health and safety of visitor s

to the historic site, but a robust longer t erm management solution was required.

The arsenic-contaminated material was classified as hazardous waste, and therequirement s for handling, t ransport ing and disposing of it were investigatedin detail. Among a number of potential remediat ion options, the best was the

Dolocrete tr eatm ent a chemical fixation and imm obilisat ion technique. TheNSW Depart ment of Environment and Climate Change provided a specific

immobilisation approval that permitt ed the use of t hat t echnique. The aim wasto immobilise the arsenic in the mineral matr ix using a magnesium oxide based

binder. This would allow t he reclassification of the material from hazardousto indust r ial waste, for disposal to a licensed waste facility. The desired

rehabilitat ion outcome was to significantly reduce the potent ial risks to humanhealth and the impact on t he surrounding environment.

To manage t he potent ial occupat ional health and safety (OHS) r isks to wor kers

during the project, full-t ime project and OHS supervisors were engaged toensure that all works were carr ied out in accordance wit h the approved OHS

management plan.

Aft er approximat ely 10 1tonnes of t he mater ial was stabilised, laborator y analysis

confirmed that t he treatment effectively reduced the mobility of t he arsenic(and changed t he waste classification fr om hazardous to indust rial). The mater ial

was then disposed of at a licensed waste facility. The project was complet edusing clean soil from t he site to reshape the remediated area so that it was

free-draining and landscaped in harmony wit h the amenit y and fabric of t hesurrounding heritage site.

The project substant ially rehabilitated t he Yerrander ie site, reducing risks to thesurrounding environment and Sydneys water supply and improving safety for

visitors and tour ists.

(continued)


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Fencing and signage was not a long-term management solution.

Part of t he mining heri tage at Yerranderie.Source: NSW Depart ment of Industry and InvestmentMinerals and Energy.


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3.5 Securit y risk substances

3.5 .1 What law applies?

The basis for secur ity r isk substances (SRS) regulat ions is the COAG agreement of

25 J une 200 4 relating to counter-ter rorism measures. All states and territ ories haveadopted SRS regulations.

States and ter rit or ies did not need identical or even new specific legislation, but they

contr ibute t o nat ional consistency in various ways. For example, Western Australiadeveloped t he Dangerous Goods Safet y (Secur ity Risk Substances) Regulat ions2007, rather than including security risk substances in explosives regulations. This

avoids confusion or inconsistencies between safety and securit y requirementsfor ammon ium nit rate. The regulations contain guidance and definitive statutory

requirement s. The requirements of t he SRS Regulations are in addit ion to t hose of

other dangerous goods safety r egulations.

3.5.2 Types of securit y r isk substances

The fo llowing substances, ot her than Class 1Dangerous Goods, are SRSs in WesternAustralia:

solid mixtures containing more t han 45% ammonium nitr ate (AN)

ammonium nit rate emulsions, suspensions or gels.

The latter group does not include single-phase, homogeneous aqueous solut ionsof AN (as opposed to mult iphase, heterogeneous mixtures). Such solutions are

classified as Class 5.1, UN 2426 in t he ADG7 and are commonly used as fert iliser or ashot , concentrated solutions for making AN emulsion explosives. However, it includes

calcium amm onium nit rate (CAN), which is not a dangerous good under t he UNclassification system.


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Consider chemicals a securi t y r isk

The Aust ralian minerals indust ry strongly support s the need for a social licenceto operate as a complement to a regulator y licence issued by government. To

the industry, a social licence to operat e is about operat ing in a manner t hat isatt uned to comm unity expectat ions and which acknowledges that businesses

have a shared responsibility wit h government, and society more broadly, to helpdevelop strong and sustainable communit ies.

All minerals operat ions receive, store, ut ilise and dispose of chemical substances.Some of those chemicals can be used to develop materials that can be used to

harm people or proper ty. Most m inerals operations have securit y proceduresin place related to m itigat ing OHS, personnel management, environment al

performance and asset management risks.

Minerals operat ions should remain vigilant about the potent ial for people ororganisations to access chemicals used in industr y operat ions and use them

in ways for which t hey are not intended. Such an event would incur significantreputational and direct costs for an operation, the company involved and the

broader industry.

Chemicals securit y r isks can be for mally considered and m anaged in exist ing

operational r isk management processes. The Risk assessment and managementleading practice handbook (DRET 200 8b), AS/ NZS 4360 :2004 and the

mater ials stewardship philosophy provide a robust f ramework for assessing andmanaging operat ional risks throughout the value chain. The Standards Australia

/ Standards New Zealand Security risk managementhandbook (HB 167:20 06)prov ides specific guidance on managing securit y-related r isks.

Incorporat ing chemicals securit y into r isk registers allows minerals operationsmanagers to understand, identif y and manage securit y r isks. The following items

could be considered for incorporation into exist ing r isk assessment processes:

employability or desirability of the chemical

could this substance be of int erest for ter ror ist purposes?

if not , it would not require fur ther assessment

from a security perspective

supply chain vulnerability, for example

employee/cont ractor suitability assessments

inventory control measures

volumes and packaging t ransport ed

site/rout e location and accessibility

securit y awareness t raining and communication f or suppliers

(continued)


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on-site vulnerability, for example

access contro ls for chemical stor e (access onto and wit hin operat ion)

employee/contractor suitability and monitor ing

t ime and frequency of chemical storage

inventory control, including documentation and auditing

t raining in and awareness of chemicals securit y concerns

procedures for handling, use and disposal.

Leading practice operat ions in Australia have taken a life-cycle approach tocustodianship of all chemicals brought to and used on site, which also extendsto chemicals suppliers and waste disposers. They apply r isk assessment

and management processes, and typically have comprehensive chemicalsinventor ies that document accountabilities, amount s, storage conditions and

disposal methods. This is oft en implemented wit h dedicated tracking soft ware.At leading pract ice operat ions, chemicals management is factor ed into site

risk management t hrough r isk registers t hat are subject to regular andcomprehensive audits against company standards.

These exist ing comprehensive systems can be tailored to include par ticular

issues related to chemicals security risks.

Thefts of hazardous mater ial from mine sites can be dangerous. In 200 8 ,

German prosecutors brought charges of membership in a ter ror ist or ganisationagainst two men, and a third man was extradited from Turkey to face charges

of providing 26 explosive detonators. According t o German media repor ts, thealleged ter ror ists wanted t o blow up US targets in Germany and had stockpiled

hundreds of lit res of concentrated hydrogen peroxide.15 The quantit ies ofchemicals were large enough to build bombs that could have been more powerf ul

than t hose that killed 191commut ers in Madrid in 20 04 and 52 commuters inLondon in 2005 .

15 htt p:// www.welt.de/politik/ art icle2384 639/ Prozess-gegen-Sauerland-Terro risten-eroef fnet .html


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4.0 RISK MANAGEMENTPurposeThis section presents risk management strategies that may be implemented at t hecorporat e, mine site or personal level.

Key messages Substitut ion of materials or cont rol measures, such as vent ilation and

containment, can reduce exposures to hazardous substances.

Worker hazard awareness and training is of vit al impor tance.

Communication of r isks to t he community needsto be part of broader communication.

Suppliers stewardship programs can augment mine management practice.16

In July 2009, the International Council on Mining and Metals released Good practiceguidance on health r isk assessment(HRA), which describes the development ofhealth risk assessments of chemicals at mining sites. This useful document is

available on the councils website.

4.1 Worker hazard awareness

4.1.1 Mat erial Safety Data Sheet s

Material Safety Data Sheets (MSDS) were established around 30 years ago to fulfilworker s righ t t o know legislation in t he United States.

Before the 199 0s, Australian legislat ion cont rolling OHS informat ion on labels and

MSDS was poor, leading to incident s in which wor kers were not aware of hazards orhow t o handle chemicals safely. Nat ional legislat ion was introduced to ensure that

MSDS and labels meet standards and include required informat ion content .

The key documents, which can be found on t he Safe Work Australia website17, are:

National Code of Practice for t he Preparation of MaterialSafety Data Sheets, 2nd edit ion [NOHSC: 2011(20 03)]

National Code of Pract ice for the Labelling of WorkplaceSubstances[NOHSC: 2012 (1994 )] .

16 htt p:// www.icmm.com/page/ 14733/new-guidance-on-health-risk-assessment

17 ht tp:/ / www.safeworkaustralia.gov.au/swa/AboutUs/ Publications/ NationalStandards/ IndexofNati onalStandardsCodesofPracticeandrelatedGuidanceNotes.ht m


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LegislationThe various OHS Acts require t hat employers provide infor mat ion, in the form of anMSDS, to allow wor kers to handle hazardous substances safely. Even when a product

is not classified as a hazardous substance or a dangerous good, it is recommendedthat an MSDS be prepared for the mine site to enable workers and managers to stor e

and handle the product safely. A similar approach should be taken to waste mater ialthat needs to be disposed.

Employers responsibilit ies

Employers have the fo llowing responsibilities:

They must provide the informat ion needed to allow the safehandling of hazardous substances used at work.

They must ensure that all employees have ready access to

MSDS (either as paper copies or in databases). They should encourage employees to read MSDS for the hazardous

substances that workers may be exposed to in t heir wor k.

MSDS on site must be dated and current (within five years of the issue date).

In some states, mining legislation requires t hat a r isk assessmentof every product be conducted and the r isks be cont rolled th roughsafe wor k procedures or ef fect ive contro ls. This occurs by a default

reference to a guideline, but is nevert heless a legal requirement.

Mine operator s that directly impor t chemicals must ensure that those chemicals arelisted in the Australian Inventor y of Chemical Substances, which is managed t hrough

the National Industr ial Chemicals Notification and Assessment Scheme (NICNAS).18 Inthe case of a mixt ure or blended product, such as a lubricant, its component s must

be listed. In addition, the m ining company becomes responsible for preparing anMSDS to m eet t he legal guidelines.

New chemicals coming on sit eThe following r ules apply when a new chemical comes onto a m ining site:

Procedures must be available to control and assessnew products or chemicals being introduced.

Before a hazardous substance is used at t he site, an MSDSmust accompany the first supply of the substance.

A r isk assessment must be conducted and signed off by a competent person.

Any necessary contr ols on the use of t he substancemust be established in the workplace.

Aft er t he risk assessment , a procedure must be generated to ensurethat t he workers can handle the hazardous material safely.

Figure 4 .1shows a sample checklist for a risk assessment .

18 ht tp:/ /www.nicnas.gov.au


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Figure 4 .1 Sample r isk assessment checklistIdentification (Complet ed By Person Bringing Chemical t o site)

Product Name:

Supplier:

Site: Locat ion:

Department/Contractor:Person Requiring Product :

Intended use:

Applicat ion Method: Average use (eg lit res/ hour):

Frequency of use Daily: Weekly: Monthly: Hour in use:

Dangerous Goods Class: Poison Schedule: UN No:

Storage Quant it ies: Container size:

Storage Location:

Risk Assessment (Completed By Safety Officer)

High Medium Low

1. Eye

2. Inhalation

3. Skin4. Ingestion

5. Fire hazard

6. Overall Rating

Cont rol (Completed By Safety Officer)

Determine t he appropriate level of control from the evaluation above.

1. Can the use of this product be avoided or eliminated?

2. Are safer substitut es available

3. Can the product be isolated

4. Engineering contr ols to reduce t he risk

Open ventilation Barricades / Guards

Forced ventilat ion Fire extinguisher

Atmospheric Monitoring TrainingAdditional lighting Writt en procedure

Warning signs other

5. What special personal prot ective equipment is required

Splash proof goggles Full Face Respirator

Full face shield Ai r flow hood / Mask

Standard Rubber gloves Disposable Coveralls

Special Gloves PVC Apron/coveralls

Particulat e Mask other

Half Face Respirat or

Environment (Completed By Environment al Superint endent)

The product (or components) is reportable under the National Pollutant Inventory?

Storage containment / bunding required?Special waste disposal requir ements?

Spill cont rol pr ocedures are necessary?

Stores (Completed By Store Superint endent)

Storage Compatibility:

Stor age Requirement s:

Recommendat ions/Act ions/Comments

Safety Environment Warehouse Technical Expert

Reviewed by

Signed

Date

Department Manager Approval

Signature: Date:

Source: Newcrest Mining Lt d


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Waste materialsWaste mat erials should also be assessed and an appropr iate MSDS and label shouldbe prepared to ensure that the wor kers handling the dr ums of material on site or off

site can do so safely.

RegistersAll hazardous mater ials on site must be on a site register, which is oft en a

computerised MSDS database.

For all hazardous mat erials, the register must include the product name, the MSDS,the quantit y, and the location

hazardous materials managment handbook

Documents