A guide to leading practice sustainable development in mining

More documents

Recommendations

Info

Geochemical assessment aims to identify the distribution and variability of key geochemical parameters (such as sulfur content, acid neutralising capacity and elemental composition) and acid generating and element leaching characteristics. A basic screening level investigation is essential and should commence at the earliest possible stage. The need and scope for detailed investigations will depend on the findings of initial screening. Since some studies such as leach tests or sulfide oxidation rate measurements require a long time frame to provide the necessary data, it is important to initiate this work well ahead of key project milestones. Reference to other mining operations in the region, particularly those situated in the same stratigraphic or geological units may provide empirical information on the likely geochemical nature of similar ore types and host and country rocks. The Pine Creek Geosyncline in the far north of Australia is renowned for its propensity for acid mine drainage potential in virtually all gold mines that operated in the 1970s and 80s. Early indications can also be provided by exploration drill core where it is leading practice to log key indicators such as sulfide and carbonate type, abundance and mode of occurrence. All samples should be analysed for total sulfur content as a minimum, and include key environmental elements in all drill core assays. Mineralogical investigations should examine the type and mode of occurrence of sulfide and carbonate minerals. A number of procedures have been developed to assess the acid forming characteristics and metal leaching behaviour of mine materials. The most widely used screening method is based on the Acid Base Account (ABA) which is a theoretical balance between the potential for a sample to generate acid and neutralise acid. The simplest form of the ABA is known as the Net Acid Producing Potential (NAPP). Some sulfur minerals do not generate acid (but may contribute to metalliferous drainage), and there are different forms and reactivities of AMD generating minerals and AMD neutralising minerals. As a result, there is a level of inherent uncertainty in prediction based solely on the theoretical ABA. Mineralogical investigations, elemental analysis, sulfur and carbonate speciation, acid neutralising capacity, reactivity, and the Net Acid Generation (NAG) test (a rapid direct oxidation procedure) are used to address this uncertainty. AMD prediction is greatly enhanced by using a combination of tests, in particular independent tests such as NAPP and NAG. Sampling Sample selection is a critical task and must be given careful consideration at all stages of a project. Samples should represent each geological material that will be mined or exposed and each waste type, for current and projected mine plans. Sampling design normally utilises drill hole cross-sections through the deposit. The number and type of samples will be site-specific and will depend on the phase of project development, but must be sufficient to adequately represent the variability/ heterogeneity within each geological unit and waste type. Factors such as grainsize, structural defects, alteration, brecciation, veining, etc., must therefore be considered in sample selection. As a minimum requirement, through the exploration phase to final feasibility, all drill hole samples should be assayed for total sulfur. A GUIDE TO LEADING PRACTICE SUSTAINABLE DEVELOPMENT IN MINING 47
Although drilling and sampling will focus on ore zones in the exploration and pre-feasibility phase, samples of host and country rock should be increasingly represented as the project develops so that adequate data are available to produce block models and production schedules by geochemical waste types. Key sampling guidelines are listed below (Scott et al., 2000): Drill core and percussion chip samples should represent no more than 10 metre intervals and cover individual geological types and ore types. Each composite sample should not be obtained from more than one drill hole. Each sample should be approximately 1-2 kg. The sample should be crushed to nominal 4 mm size, then riffle split to produce 200-300 g for pulverising to minus 75 micron. The minus 4 mm and pulverised splits should be retained for testing. Pre-mining Few mineral resources are homogeneous and relatively little is understood about them and their host rocks in the pre-mining phases. However, it is important during the pre-mining phases that the project team, including geologists, mine planners, environmental scientists and AMD experts, ensures that an adequate geological and geochemical database is compiled to clarify baseline conditions and the risk of AMD. A typical progressive test work program is summarised in Table 3. Knowledge of the likely wastes that will be generated and materials exposed and the constraints that these will place on the mining operation is vital (Scott et al., 2000). A detailed Closure Plan needs to be developed and costed for a site during the feasibility phase. This must remain a “living document”, as the mine proceeds, with regular reviews and updates based on new technologies, stakeholder inputs, changing mine conditions and community expectations. Monitoring Purpose The main purpose of an AMD monitoring program is to provide relevant information that can be used by site planners and managers as a basis for informed decision making. An effective monitoring program will facilitate the implementation of an AMD Management Plan for the site that can reduce or eliminate the impacts of AMD on the environment, community and mining operations. 48 LEADING PRACTICE SUSTAINABLE DEVELOPMENT PROGRAM FOR THE MINING INDUSTRY
Page 1 and 2:
LEADING PRACTICE SUSTAINABLE DEVELO
Page 3 and 4:
Disclaimer This publication has bee
Page 5 and 6:
3.0 DEVELOPMENT AND CONSTRUCTION 61
Page 7 and 8: ACKNOWLEDGEMENTS The Leading Practi
Page 9 and 10: viii LEADING PRACTICE SUSTAINABLE D
Page 12 and 13: 1.0 INTRODUCTION The Purpose and La
Page 14 and 15: Airborne Contaminants, Noise and Vi
Page 16 and 17: Water Management (LP Water) This ha
Page 18 and 19: Site water team Corporate managemen
Page 20 and 21: Sustainable Mining There is no one
Page 22 and 23: Mining the resource efficiently. Th
Page 24 and 25: Efficiency SUSTAINABLE MINING PRACT
Page 26 and 27: LOCATION: Vilabouly District, Savan
Page 28 and 29: Leading Practice The handbooks in t
Page 30 and 31: 2.0 PRE-DEVELOPMENT: MINERAL EXPLOR
Page 32 and 33: The application of high standard en
Page 34 and 35: The Business Case for Sustainabilit
Page 36 and 37: The information obtained from these
Page 38 and 39: conditions are appropriate. In NSW,
Page 40 and 41: Such richness also brings challenge
Page 42 and 43: The dunefields of Shelburne Bay had
Page 44 and 45: Community Engagement in the Early S
Page 46 and 47: Baseline studies and social impact
Page 48 and 49: Upon completion of the study, resea
Page 50 and 51: The scenarios envisaged for the Wat
Page 52 and 53: 2. Reflections on the significance
Page 54 and 55: Engaging with Indigenous communitie
Page 56 and 57: Figure 2.9 - A New Township under C
Page 60 and 61: Regardless of the project phase (ex
Page 62 and 63: Evaluating Performance: Monitoring
Page 64 and 65: For these reasons, it is important
Page 66 and 67: Risk Management and Exploration Exp
Page 68 and 69: Post-mining & closure Resource deve
Page 70: level of family diversity was maint
Page 73 and 74: Introduction The development and co
Page 75 and 76: MINE: Mt Todd LOCATION: Near Kather
Page 77 and 78: Airborne Contaminants, Noise and Vi
Page 79 and 80: Biodiversity Management During Deve
Page 81 and 82: Rather than taking a generic approa
Page 83 and 84: Step 2: Working in collaboration On
Page 85 and 86: course was designed to train and pr
Page 87 and 88: Adjustments for changes in the mine
Page 89 and 90: indicators of high importance durin
Page 91 and 92: Operating major mining projects pre
Page 93 and 94: the earliest stage of development,
Page 95 and 96: Watercourse diversions In order to
Page 97 and 98: Figure 3.7 - Morwell River after di
Page 99 and 100: tailings disposal techniques contin
Page 101 and 102: Figure 4.2 - Predicted blast overpr
Page 103 and 104: Responsible management of biodivers
Page 105 and 106: Leading practice management of wate
Page 107 and 108: MINE: Pierina Mine LOCATION: Distri
Page 109 and 110:
Weipa - a sustainable approach to t
Page 111 and 112:
Adopting the International Cyanide
Page 113 and 114:
Box 1: Major recent incidents invol
Page 115 and 116:
MINE: Chatree gold mine LOCATION: P
Page 117 and 118:
The audit outcomes also highlight t
Page 119 and 120:
Mercury for gold recovery in small/
Page 121 and 122:
Figure 4.9 - Geological control to
Page 123 and 124:
highest rating group for the whole
Page 125 and 126:
Figure 4.13 - Beverley uranium mine
Page 127 and 128:
from 2.5 - 3.0 tonnes/man-shift to
Page 129 and 130:
Figure 4.17 - Sunrise Dam TSF Taili
Page 131 and 132:
Dry stacking bauxite residue is now
Page 133 and 134:
Once the water is used underground
Page 135 and 136:
The Rio Tinto “Excellence in Wate
Page 137 and 138:
Background Image: Sourced from GOOG
Page 139 and 140:
Company policies and government reg
Page 142 and 143:
5.0 MINE REHABILITATION AND CLOSURE
Page 144 and 145:
Closure involves the implementation
Page 146 and 147:
Biodiversity and Closure Introducti
Page 148 and 149:
e better than the high standard bei
Page 150 and 151:
Figure 5.7 - Pasture and shelter tr
Page 152 and 153:
The Argyle Diamonds case study (see
Page 154 and 155:
support and on site accommodation a
Page 156 and 157:
Having the right information to mak
Page 158 and 159:
Figure 5.13 - Misima after rehabili
Page 160 and 161:
In January 2011, the PNG government
Page 162 and 163:
MINE: Former lignite mines LOCATION
Page 164 and 165:
Fig 5.16: Former Minister Stein Coa
Page 166 and 167:
Figure 5.19 - Rehabilitated mine si
Page 168 and 169:
Figure 5.21 - Pit water treatment p
Page 170 and 171:
Final Rehabilitation Rehabilitation
Page 172 and 173:
Figure 5.23: Aerial view of Area 4
Page 174 and 175:
Landform construction In general, e
Page 176 and 177:
The Hsin-Chen Shan quarry terrain i
Page 178 and 179:
Figure 5.29 - Spreading topsoil at
Page 180 and 181:
Risk Management Risk at closure and
Page 182 and 183:
During the 1980s and 1990s, a numbe
Page 184 and 185:
An example of direct vegetation is
Page 186:
Water Management Central to a mine
Page 189 and 190:
Department of Resources, Energy and
Page 192 and 193:
GLOSSARY AND ACRONYMS Abandoned min
Page 194 and 195:
Biodiversity offsets Conservation a
Page 196 and 197:
Cultural heritage Cultural heritage
Page 198 and 199:
Engagement At its simplest, engagem
Page 200 and 201:
High rate thickener A thickener thr
Page 202 and 203:
NAPP Net Acid Producing Potential,
Page 204 and 205:
Product stewardship This is perhaps
Page 206 and 207:
Risk management process The risk ma
Page 208 and 209:
Sustainable development Sustainable
show all

A guide to leading practice sustainable development in mining

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?