MINING: Metallic Ores and Minerals
Technical Support Document
International Training Workshop
Principles of Environmental Enforcement
T
WWF
SEDESOL
Ministry ol Housing,
Spatial Planning,
and the Environment
(VROM) The Netherlands
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MINING SUPPORT PACKAGE
METALLIC ORES AND MINERALS
July 14, 1995
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ACKNOWLEDGEMENTS
This document is one of five Technical Support Documents that have been developed to
accompany international training workshops on the Principles of Environmental
Enforcement. They were developed as resource documents for government officials and
others who are motivated to try to reduce the adverse environmental impacts from
activities described in the case studies used for the course. The five case study areas
include:
o Mining (Metallic ores and Minerals),
o Petroleum Refining and Petrochemicals,
o Residential and Industrial (Solid) Waste Disposal
o Tourism, and
o Deforestation.
The documents provide an overview of the environmental impacts, pollution prevention
and control opportunities, range of institutional mechanisms to control adverse impacts,
and an annotated bibliography of selected reference materials. They do not address
institutional and program development issues surrounding regulatory and enforcement
programs. These topics, as well as country specific program examples are developed in
the Proceedings of the International Conferences on environmental compliance and
enforcement, UNEP institution-building workshop materials and new capacity building
documents under development for the Fourth International Conference scheduled to be
held in April, 1996 in Thailand.
International workshops on the Principles of Environmental Enforcement provide an
opportunity for governmental and non-governmental officials to discover and apply the
definitions, frameworks and principles to develop a successful management approach,
compliance strategy and enforcement program for any environmental problem in any
cultural or legal setting and to explore negotiated resolution of enforcement problems.
The Principles of Environmental Enforcement text and training was developed by the
U.S. Environmental Protection Agency in collaboration with the government of Poland
and in cooperation with the government of the Netherlands. It was adopted as a basis for
international exchange after having been successfully presented with this purpose in mind
at the Second International Conference on Environmental Enforcement held in
Budapest, Hungary, September 1992.
This document was produced under a Cooperative Agreement between the World
Wildlife Fund and the U.S. Environmental Protection Agency in cooperation with the
Netherlands Ministry of Housing, Spatial Planning and the Environment, The United
Nations Environment Program IE, and SEDESOL the Mexican Social Development
Ministry. The topic is one of five identified by an international Executive Planning
Committee for new case studies and stand-alone technical support materials to be used
in workshops on the Principles of Environmental Enforcement launched at the Third
International Conference on Environmental Enforcement held in Oaxaca, Mexico, April
25-28, 1994. Partial funding was also provided by the United States Agency for
International Development.
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Mr. Rick Sturgess of Apogee Research Inc., was principal author of the document, under
the technical direction of Ms. Cheryl Wasserman in U.S. EPA's Office of Enforcement
and Compliance Assurance. A special note of appreciation to Mr. Steve Hoffman,
USEPA's Office of Solid Waste and Emergency Response and international expert on
mining, Mr. Robert Gosik of USEPA's National Enforcement Investigation's Center, Ms.
Nancy E. Dean and Mr. Ray Aufmuth, of the US Bureau of Mines for their helpful
comment and to Mr. William Eichbaum, International Vice President of the World
Wildlife Fund for his support.
This Technical Support Document is intended to accompany the Principles of
Environmental Enforcement Text, U.S. EPA, which describes the basic elements and
approaches for establishing effective compliance strategies and enforcement programs.
As a supplement to international efforts to advance effective environmental compliance
and enforcement programs, the readers are referred as well to the UNEP IE training
manual on Institution Building for Industrial Compliance and Proceedings of the series of
International Conferences on Environmental Compliance and Enforcement for further
discussion of these programs.
Requests for copies and comments on this document can be directed to:
TO:
Ms. Cheryl Wasserman
Associate Director for Policy Analysis
Office of Federal Activities
United States Environmental Protection Agency
Office of Enforcement and Compliance Assurance
401 M Street, MC 2251
Washington, D.C. 20460
FAX 1-202-260-0129
PHONE 1-202-260-4486
or
Mr. Jo Gerardu
The Netherlands Ministry of Housing,
Spatial Planning, and the Environment
IPC681
P.O. Box 30945
2500 GX DEN HAAG
The Netherlands
FAX 31-70-339-1300
PHONE 31-70-339-2536
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TABLE OF CONTENTS
1. INTRODUCTION AND SUMMARY 1
1.1 Purpose and Overview of the Mining Support Package 1
1.2 Metals Mining/Processing and the Environment 1
1.3 Towards Sustainable Development: Pollution Prevention and
Control 3
2. PROFILE OF THE MINERAL INDUSTRY AND OVERVIEW OF THE
MINING AND MINERAL PROCESSING INDUSTRY 6
2.1 Extraction Methods 6
2.2 Beneficiation 7
2.2.1 Amalgamation 7
2.2.2 Flotation 8
2.2.3 Leaching 8
3. PRINCIPALMINING-RELATEDENVIRONMENTALPROBLEMS,AND
ASSOCIATED POLLUTION PREVENTION AND CONTROL
OPTIONS 10
3.1 Mining-Related Water Pollution and Options for Prevention and
Control 10
3.1.1 Acid Mine Drainage and Acid Rock Drainage 11
3.1.2 Water Contamination From Beneficiation 17
3.1.3 Hydrologic Impact and Erosion of Sediment 18
3.1.4 References for More Information on Water Pollution
Prevention and Control 20
3.2 Air and Noise Pollution and Options for Prevention and Control .... 20
3.2.1 Dust 20
3.2.2 Fumes and Exhaust 21
3.2.3 Noise 21
3.2.4 Blasting 21
3.2.5 References for More Information on Air and Noise Pollution
and Prevention Options 22
3.3 Environmental Impacts of Non-Modern and Small-Scale Mining
Methods 22
3.3.1 References for More Information on Non-Modern and Small-
Scale Mining 23
3.4 Mine Closure 23
4. PLANNING, MONITORING, ENFORCEMENT AND COMPLIANCE
APPROACHES 26
4.1 Using Environmental Impact Assessments During Planning 27
4.2 Monitoring Active Mines 27
4.3 Establishing Technical and Performance Standards and Permitting the
Mining Industry 28
4.4 Compliance Monitoring and Enforcement Programs 29
4.5 Mining Associations and General Sources of Information 29
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5. APPENDICES 30
5.1 APPENDIX 1: Sample Environmental Regulations 30
5.1.1 Sample Outline of An Environmental Assessment Report .... 30
5.1.2 Excerpts from the Bolivian Mining Code 31
5.1.3 Excerpts from United States EPA Regulations 32
5.2 APPENDIX 2: Sample Cost Estimates 36
5.3 APPENDIX 3: Checklist for Environmental Impact
Assessments of Proposed Mining Projects 38
5.4 APPENDIX 4: The Berlin Accords 46
5.4.1 Addressed to the Mineral Sector 46
5.4.2 Addressed to Development Assistance Agencies 47
5.5 APPENDIX 5: Annotated Bibliography 49
5.5.1 Accessing Information on Mining 49
5.5.2 The Mining Process 51
5.5.3 Pollution Prevention and Environmental Control
Technologies 52
5.5.4 Acid Mine Drainage and Leaching 53
5.5.5 Information on Mining and Mineral Processing from EPA's
Office of Solid Waste, Mining Waste Section 54
5.5.6 International Sources of Information 56
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MINING SUPPORT PACKAGE
METALLIC ORES AND MINERALS
1. INTRODUCTION AND SUMMARY
This document is an overview of the environmental impacts of metal mining and
processing. It is general in nature and is provided as an introduction to some of the methods
available to prevent, control, and mitigate these impacts. Metals are a valuable natural resource
for many countries and a necessity for the economies of all nations that depend on metal
products. However, unless proper controls are taken in mining and processing metals, serious
environmental damage can result. The environmental effects of mining and/or mineral
processing include: alteration of the landscape with pits and waste rock; subsidence of the land
over underground mine workings; pollution of surface water with acid drainage and metals from
waste rock and tailings and chemicals from mineral beneficiation; damage to sensitive
ecosystems that support fish and wildlife; and human health risks from contaminated water
sources. To prevent these impacts, government policy-makers are taking more steps to strongly
encourage pollution prevention options and to adopt regulatory and enforcement strategies for
minimizing the harmful environmental impacts of mining and mineral processing.
1.1 Purpose and Overview of the Mining Support Package
This document gives a brief description of the metals mining process, examines some of
the options for preventing environmental damage from mining, and outlines various strategies
for regulating mining practices to insure that environmental impacts are controlled. Examples
of environmental management approaches are presented so that government planners can make
informed decisions on the approaches best suited to their needs.
Since this document is intended as an overview document, those wishing to explore the
subject more thoroughly should consult the references listed in the Sources of Additional
Information section for additional reading material.
1.2 Metals Mining/Processing and the Environment
In many countries, mining is performed on a large scale, using heavy equipment and
explosives, advanced beneficiation technologies, and a sizable work force. These operations
may be owned or managed by the public sector, the private sector, or shared jointly between the
two. The mining industry often extracts and processes a variety of metals, minerals, and gems
within a single country and generates profits, tax revenues, jobs, and foreign exchange earnings
for mine owners, employees, and host country governments. While the economic benefits to
private companies, governments, and employees may be substantial, by its very nature the
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extraction of a non-renewable resource from the earth has environmental effects. Table 1
summarizes some of the potential effects of industrial mining on the environment that are
discussed in more detail in the support package.
Table 1: Steps in Mining and Beneficiation and Their Environmental Impact
Mining
Process
Site
Preparation
Blasting/
Excavation
Crushing/
Concentration
Leaching
Water Pollution
Increased turbidity
from erosion due to
removal of
vegetation
Acid Mine Drainage
(AMD)
Increased turbidity
from erosion of
soils
Petroleum wastes
from trucks
Surface
Contamination from
runoff
Ground water
contamination from
acid waste water
discharges
Acid Waste Water
Discharges
Acid Rock Drainage
Surface and ground
water pollution
from ruptures in
pipes or ponds
holding leach
solution
Air Pollution
Exhaust from construction
vehicles, dust
Dust blown to
surrounding area
Exhaust from heavy
machinery
Dust created during
transportation
Heavy metals in dust run
off into surface water and
leaches into ground water
Solid Waste
Clearing Debris
Overburden if not
reused
Waste rock
Additional waste
rock
Tailings
Sludges from
neutralization of
contaminated water
Land, Habitat, Wildlife
Deforestation and habitat
loss from road and site
construction
Loss of habitat
Increase in soil erosion
Loss of plant population
from dust and water
pollution
Reduction in groundwater
resulting from pumping
for use in processing
Loss of fish population
from water pollution
Nearby structural damages
from vibration and settling
Competition for land use
Loss of habitat
Loss of plant population
from water pollution
Loss of fish and water
fowl population from
water pollution
Loss of terrestrial habitat
through soil contamination
and destruction of
cover/food sources
In addition, small-scale mining, common in many countries for the extraction of gold
and other minerals, can cause similar kinds of environmental damage and also may strain the
ability of surrounding residential centers to provide adequate services to a rapidly increasing
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population. Many governments are challenged with balancing the economic benefits of mining
with the environmental costs of this activity.
1.3 Towards Sustainable Development: Pollution Prevention and Control
Since the mining industry is important to the economies of many countries, and the
mining process is often unavoidably destructive, governments often choose to tolerate some level
of environmental damage resulting from mining activities. Many, but not all, of the
environmental impacts of mining can be minimized through careful planning, monitoring, and
enforcement of clear, well-defined regulations. The use of pollution prevention technologies and
environmental controls also can substantially reduce the volume of contaminants released and
the concentration of the contaminants discharged into the surrounding environment. In some
cases, these pollution prevention approaches may also be economically beneficial to mine
operators because they may decrease the process chemicals needed, and therefore the cost of
producing a given amount of mineral. The list below summarizes some of the environmental
control technologies and regulatory approaches discussed in this document.
Summary of Pollution Prevention, Control, and Management Options
Water Pollution Prevention and Control
• Diversion Systems - Reducing the amount of contaminated water produced by
channeling runoff away from exposed mine pits and waste dumps.
• Drainage Ditches - Channeling contaminated water into containment ponds for
treatment or recycling.
• Containment Ponds - Constructing ponds to hold contaminated water for
treatment which prevent contamination of ground or surface water e.g. synthetic
or clay liners.
• Recycling Systems - Reusing contaminated water, after appropriate filtering or
treatment, in the extraction process for dust elimination or drilling.
• Subsurface drainage systems and barriers - Collecting or deflecting groundwater
prior to contact with exposed mine pits, preventing groundwater contamination.
• Liners - Underlinings for leach units or tailings ponds to prevent or minimize
leakage of contaminated water to ground or surface waters.
• Runoff Controls - Providing means for stabilizing, filtering, and/or settling out
soil materials which can be picked up during storm runoff for the purpose of
controlling erosion of disturbed areas and limiting stream sedimentation.
• Wastewater Treatment - Including the use of lime to reduce acidity and settle out
metals and other solid contaminants.
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• Wetlands - An experimental and unproven technology, constructed wetlands rely
on natural processes of wetlands to remove water contaminants before discharge.
Air Pollution Prevention and Control
• Dust Elimination Technologies - Water sprinklers used to reduce dust created
during excavation and transport.
• Dust Suppressant Agents - Compounds such as magnesium chloride can be used
to reduce dust in solid piles and tailings subject to significant wind erosion.
These compounds can harm plant and aquatic life, however, and should only be
used where it can be shown that they will not pose an environmental threat.
Closure and Reclamation Approaches
• Mine Closure and "Capping" - Covering exposed mine pits, tailings, and waste
rock dumps with natural or natural/synthetic material to reduce contamination
of groundwater and creation of dust once mines are no longer active.
• Revegetation and Regrading - Using plant cover and landscape alteration to
reduce erosion, dust, and runoff contamination, reintroduce native species to the
former mine site, and allow alternative uses of the land.
Sample Planning, Monitoring, Enforcement, and Compliance Approaches
• Regulations - Enacting laws and rules governing technology use, acceptable
contaminant levels, reporting and monitoring procedures, penalties, fines,
reclamation bonds, etc.
• Environmental Impact Assessments - Preparing detailed reports that estimate
environmental impacts of proposed sites and present plans for complying with
regulations and managing potential future environmental problems.
• Mine site plan, review, approval and permitting - Reviewing alternative
approaches to mine design and extractibn/beneficiation prior to issuance of mine
permits, and exploring strategies that might minimize environmental impacts.
This approach may also include plans for mine closure, land reclamation and
appropriate environmental management systems.
• Self-monitoring, Self-reporting - Using company-managed environmental
monitoring and reporting systems to supplement government-run enforcement
efforts. This approach may improve cooperation between government and
industry, reduce costs, and still provide adequate environmental protection.
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The approaches selected by governments to manage the environmental impact of mining
depend on a variety of criteria, including the size and breadth of the mining industry, nature of
the mine environment, the funds available for enforcement and inspection, the availability and
local costs of new technological solutions, and the current relationship between government and
mine operators in each country. Since no single approach is appropriate to all countries or
regions within countries, this support document can only offer some approaches for
consideration. Nevertheless, it is hoped that this information will allow policy-makers to more
fully appreciate the problem while taking advantage of the full range of potential solutions.
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2. PROFILE OF THE MINERAL INDUSTRY AND OVERVIEW OF THE MINING
AND MINERAL PROCESSING INDUSTRY
Mining takes place in a wide range of countries, in all regions of the world, in different
topographic and climatic conditions, and at all levels of economic prosperity. Many of the same
basic principles are applied whether one is extracting copper from the mountains of Zaire, or
bauxite from Australia. Since mineral deposits have fixed locations there is little choice as to
where the industry may seek to develop. Although governments may choose to control who may
mine a country's national resources, many of the same large multinational corporations manage
mining operations in countries around the globe. Often these companies operate through joint
ventures with government owned firms, or may compete against public or private companies run
by host country nationals.
Since many companies operate mining operations on a global scale, and the minerals
extracted are often subject to prices determined on world markets, there is less variation in
technologies used in countries of different economic and technological development than in other
more localized industries. Although the wage scales of local workers in different countries and
the costs of procuring specialized equipment do have some bearing on technologies used in the
mining industry, the basic processes are still quite similar whether a mine is located in Peru,
Russia, or the United States. Even mining conducted on a small-scale by individual
"prospectors" still requires the basic operations of excavating non-valuable cover, extracting the
target mineral, and processing the raw ore to concentrate the valuable elements. This section
primarily deals with industrial-scale mining techniques, and the particular problems of small-
scale mining will be presented later in the support package.
Primary steps that mine operators will perform include extraction, milling, and/or
leaching. Extraction is the process of mining or removal of ore from deposits in the ground.
Once the ore is removed, additional milling processes are required to isolate the valuable mineral
from the remaining wastes. Depending on the grade of the ore at metal mines, ore may be
initially crushed, then either processed further by beneficiation or concentrated through heap
leaching. Beneficiation employs one or more methods to separate material into two or more
constituents, at least one of which is the desired product. These methods are used to prepare
ores for further intensive processing and use the differences between the physical properties of
the various minerals in the ore to concentrate the target mineral. Beneficiation processes rely
on differences such as size and density. Following beneficiation, the valuable mineral can be
further concentrated through a variety of metallurgical processes. Heap leaching of ore is
performed by stacking the ore and applying chemical solutions directly through a sprinkler. The
solutions then percolate through the ore, dissolving the metals. The metal-laden solution is then
collected at the base of the pile and pumped to a processing plant where the metal is recovered
from the liquid.
2.1 Extraction Methods
There are two basic ways in which minerals are mined-surface and underground. The
choice of extractive technique depends on the type of mineral being mined, the shape, size, and
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location of the ore body, and cost considerations. Solution mining is a specialized process used
on certain types of metal deposits and will be discussed briefly in the section on leaching below.
Surface and underground mining are more common and are used to extract a wide variety of
minerals.
Surface or open pit mining is used for large, near-surface deposits which have a low
commodity value per unit of volume. Rock is drilled, blasted, loaded into trucks and hauled to
a facility where it is crushed and ground to a uniform size. Surface mining requires the removal
and disposal of a layer of soil and rock containing no minerals, commonly called the
overburden. A second layer of rock, known as waste rock, containing low concentrations of ore
is also removed and, in some cases, disposed of. Once the high-quality deposit is exposed,
excavation continues, with further disposal of surrounding low-grade waste rock, until the
valuable body of ore has been removed. The high-quality ore is broken into pieces that can be
easily transported and moved to a crushing plant for further processing.
Underground mining methods are used when mineralized rock occurs deep beneath the
Earth's surface. To reach the ore body, remove ore and waste, and provide ventilation, miners
must excavate either a vertical shaft, a horizontal adit, or an inclined passageway. Within the
ore deposit, horizontal passages called drifts and crosscuts are developed on several levels to
access mining areas called stapes. Blasted rock is hauled away from the slopes by trains,
loaders, or trucks that may bring it directly to the surface or transport it to a shaft where it is
hoisted to the surface and sent to a crushing facility.
In both underground and surface operations, extraction of ore and wastes requires the use
of heavy machinery and explosives. A variety of bulldozers and shovels as well as hand-held
drills and jackhammers are used to remove soil and soft waste rock. Explosives such as
mixtures of ammonium nitrate and fuel oil are used to blast away harder rock deposits. In
addition, small transportation equipment is used to transport ore to the surface of underground
mines, and large loaders and trucks are used to carry ore away from the mine site for further
processing.
2.2 Beneficiation
Mined ore, with a few exceptions, must be beneficiated before further processing.
Beneficiation, commonly referred to as milling, is the processing of ores to regulate the size of
a desired product, remove unwanted constituents, and/or improve the quality, purity, or assay
grade of a desired product. Processing methods range from simple washing screening and
drying, to highly complex methods used to process copper, lead, zinc, silver, and gold ores.
2.2.7 Amalgamation
Gold and other metals, when brought into contact with metallic mercury, will
amalgamate — meaning that the liquid mercury will alloy with the surface gold to form a
mercury-coated particle which has surface properties similar to those of pure mercury. The
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amalgamated particles will coalesce or cling together much as drops of pure mercury will collect
into a single puddle. When mercury has amalgamated as much gold as possible, the result is
a gray plastic mass. When this mass is heated, the mercury distills off, leaving behind metallic
gold.
2.2.2 Flotation
Metals can also be concentrated through flotation. Flotation is a method of mineral
separation in which a number of reagents selectively float or sink finely crushed minerals in an
enclosed flotation cell. These techniques use physical and chemical properties of the target
minerals along with process chemicals to separate relatively pure minerals from remaining
wastes. The wastes, including the liquids used in the process, are then discarded. The solid
mine wastes from flotation are known as the mine tailings.
2.2.3 Leaching
In some instances, low grade ore is not simply discarded after extraction. Instead, low
concentrations of ore are extracted through a variety of beneficiation processes known as
leaching. All leaching methods involve pouring a solution (commonly acid or cyanide) over
rock to dissolve metals into a solution for later extraction.
There are four main types of leaching: dump, heap, vat, and in situ. In each type, the
basic components of the process are deposits of low grade ore, a leaching solution, and a
holding/recovery area used to extract the desired metal from the solution. The leaching process
used depends on the concentration of metals in the ore and the economics of the mining
operation. For instance, dump leaching is often used on copper ore with 0.05 percent or more
copper content, while heap leaching is used for higher grade ores with copper concentrations
between 0.5 and 1 percent.
In situ leaching, also called solution mining, is an alternative to the underground and
surface techniques described above. Solution mining involves pumping a reagent, such as a
sulfuric acid solution, directly into the ore body. The reagent dissolves the metals hi the ore and
the solution is collected by various means and then pumped to the surface for later extraction
through electrical/chemical techniques.
Dump leaching is the most widely used and often the most environmentally-damaging
leaching process. It involves the creation of large dump piles of low-grade crushed and
uncrushed ore that cannot be profitably processed through other methods. These leach dumps
often rise to heights of up to 60 meters and contain several million metric tons of rock.
Precipitation, and additional acidic leach solution is used to dissolve the desired minerals into
solution. The leaching solution is sprayed, injected, and/or washed over the dump pile, and the
solution is collected in a pond.
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Heap leaching is a modified form of dump leaching usually conducted on a smaller scale
and with higher-grade ore. The ore, usually crushed, is placed on a specially-prepared pad made
of synthetic material, asphalt, or compacted clay. Reagents typically composed of strong acids,
bases, or cyanide are used as the leaching solution.
Vat leaching requires the highest grade ore of any leaching process and involves placing
crushed ore into an enclosed vat of reagents.
In all leaching processes, the desired metals must be recovered from the leaching
solution. The leaching solution containing dissolved metals is pumped from a holding pond to
an extraction plant. Metals are recovered from the solution using chemical or electrical
processes. Once the metal has been removed from the leach solution, the solution is typically
used again in the leaching process.
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3. PRINCIPAL MINING-RELATED ENVIRONMENTAL PROBLEMS, AND
ASSOCIATED POLLUTION PREVENTION AND CONTROL OPTIONS
The typical mining methods described above create the potential for a variety of
environmental problems at many stages in the process. Heavy machinery, explosives, and
underground or otherwise hazardous working conditions common to the excavation process
present dangers to employees and surrounding residents. Reagents used in leaching or created
through natural chemical reactions with exposed mine rock can lead to contamination of streams,
rivers, or underground water sources as a result of ruptures in holding ponds or uncontrolled
runoff. Dust, often containing heavy metals and silica in various forms, created through
excavation and transportation of ore, pollutes the air, land, and water surrounding the mine site.
The primary sources of environmental problems associated with each stage of the industrial
mining process have been summarized in Table 1. These environmental problems and some
common methods to minimize their impacts are discussed in the following sections.
In addition to environmental problems caused by the mining process, serious air and
water pollution problems can also be created in later stages of mineral/metal processing
operations. Smelting (melting or fusing of the ore to separate metal constituents) and coking
(producing carbon for smelting or refining by carbonizing coal in high temperature ovens) can
both result in the emission of harmful contaminants into the air. Although these refinement steps
are beyond the scope of this document, which focusses on the initial extraction and beneficiation
processes, it should be recognized that smelting operations may be located close to mining
operations so as to reduce transportation costs. An understanding of the environmental problems
caused by these processes and the pollution prevention and control options available to minimize
their impact will be important as well.
3.1 Mining-Related Water Pollution and Options for Prevention and Control
In many respects, water pollution represents the most common and most serious
environmental problem caused by mining. Metal-bearing rock that interacts with rainwater or
with process chemicals such as cyanide and mercury can lead to water pollution impacts at all
stages of the mining/beneficiation/disposal process. Principal sources of water contamination
include:
• Runoff from excavated mine pits and changes in surrounding terrain;
• Milling and leaching operations, especially when cyanide, mercury, or other
process chemicals are used in beneficiation;
• Runoff from waste and tailings dumps; and
• Leakage of process or runoff waters from pipes or holding ponds;
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Mine pits create large exposed surfaces of mineral and metal-bearing rock that can
contaminate rainfall which may eventually flow into surrounding streams or percolate into
groundwater. The excavation of mine pits results in problems of erosion, leading to an increase
of sedimentation in streams that may adversely impact wildlife and change water courses.
Changes in terrain may increase runoff and as a result reduce groundwater levels in the region
surrounding the mine site. The use of chemicals such as cyanide and mercury in beneficiation
also results in polluted wastewaters that need to be treated and/or controlled upon discharge.
These chemicals represent pollution hazards in and of themselves and also cause metals pollution
through interaction with minerals in milling and leaching operations, in waste dumps, and along
discharge pathways. Waste and tailings dumps, a solid waste problem, also contaminate runoff
as well as surrounding streams and sources of groundwater through interaction of water,
remaining metals, and residual process chemicals.
The effects of mine-related water pollution can include toxic metals and hazardous
chemical constituents in water supplies that may make water unfit to drink, reduction or
elimination of native fish, plant, and bird species that live near contaminated streams, or
reduction in groundwater available for agriculture and livestock. The thorough understanding
of local hydrologic factors coupled with the use of proper technologies to control the levels of
water pollution are especially important.
Many of the water pollution prevention and control options are relatively inexpensive and
require no special equipment, sophisticated technology, or special training to install and
maintain. Water pollution controls do work best, however, when they are planned and
implemented early in the life of a mine. This section briefly discusses the primary water control
problems and defines options that can be used in a complete system to minimize the water
pollution threat.
3.1.1 Acid Mine Drainage and Acid Rock Drainage
Acid Mine Drainage and Acid Rock Drainage are two persistent and potentially severe
pollution problems associated with the mining industry. They are caused by naturally-occurring
chemical interactions of water, air, bacteria, and exposed mine rock. The resulting
contamination of surrounding water sources with acids and dissolved metals can kill plants and
fish and, in serious cases, poison humans who drink contaminated water or eat fish and plants
from polluted rivers and streams. This section examines how Acid Mine Drainage and Acid
Rock Drainage occur, describes their environmental impacts, and explores potential measures
for prevention, monitoring, and control.
How Acid Mine Drainage and Acid Rock Drainage Occur
Acid Mine Drainage and Acid Rock Drainage occur when sulphide-containing minerals
such as pyrite and pyrrhotite, common to many mine sites, are exposed to air and water. These
minerals, which may either be present as a result of excavation or naturally-occurring, may
react with water and oxygen to create ferrous ions and sulfuric acid. With bacteria acting as a
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catalyst, the ferrous ions react further with oxygen, producing hydrated iron oxide, known as
"yellowboy". This combination of yellowboy and sulfuric acid contaminates surrounding soil,
groundwater, and surface water, producing water with a low pH level and a high sulphate, iron,
and heavy metals content. When this process occurs within a mine it is called Acid Mine
Drainage. When it occurs in waste rock and tailings piles it is known as Acid Rock Drainage.
Since the processes have similar impacts, they will be discussed together as acid drainage.
The Environmental Impact of Acid Drainage
When acid drainage occurs, acidic and metals-laden water may be carried out of the mine
site into groundwater or nearby streams and rivers. Acid drainage lowers the pH of the
surrounding water, making it corrosive and unable to support many forms of aquatic life.
Vegetation growing along streams is also affected as plant species that can survive in acidic
water replace native species.
The flow of acidic mine water can also carry toxic, metal-bearing sediment into streams.
These toxic sediments may kill waterborne plant and animal species. In the most extreme cases,
acid drainage may kill all living organisms in nearby streams. If humans are exposed to water
or fish contaminated with heavy metal, serious health effects may occur.
Acid drainage can continue to be a problem long after a mine closes. Abandoned mines
and refuse piles can produce acid damage for over 50 years. The U.S. Forest Service estimates
that 5,000 - 10,000 miles of streams in the U.S. are currently affected by acid drainage from
active and inactive mines and waste rock piles (see United States Department of Agriculture,
Acid Drainage From Mines on the National Forests: A Management Challenge. Program Aid
1505, March 1993.) Because of the difficulty and cost of acid damage cleanup, environmental
agencies often focus their efforts on prevention.
Pollution Prevention: Avoiding Acid Drainage
There are no widely-applicable technologies to stop a fully-developed acid drainage
situation. Once acid drainage occurs, there are several widely-applicable technologies to address
it. These technologies require perpetual maintenance, however. This makes it particularly
important to prevent acid drainage before it starts. Prevention of acid drainage requires control
of the basic elements of the problem: oxygen, water, bacteria, and sulphide minerals. Within
a mine, oxygen levels cannot be controlled, so Acid Mine Drainage prevention measures focus
on control of the other three parameters, particularly on water flows.
In addition, a number of computer-based predictive models have been developed that
allow mine operators and regulators to identify potential acid drainage problems early in their
development. Through the use of continuous sampling and analysis, many of the control
approaches described below can be implemented and modified appropriately with changing
conditions at the mine site.
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Controlling Water Flow
The primary strategy for minimizing acid drainage focuses on water control. A
comprehensive water control strategy works both to limit contact between water and exposed
mine rock and to control the flow of water that has been contaminated by mineral-bearing rock.
Systems for water control at mine sites require consideration of rainfall runoff as well as process
water used or produced when mine dewatering is required in excavation, concentration, and
leaching. Although the type of water controls used vary widely according to topography, rock
type, and climatic conditions, efforts typically are aimed at directing water flows to a few
containment ponds for easy treatment or evaporation. The five principal technologies used to
control water flow at mine sites are: diversion systems, containment ponds, ground-water
pumping systems, subsurface drainage systems, and subsurface barriers.
Control of Surface Water
Surface water is controlled by diversion systems, primarily made up of drainage ditches.
Some drainage ditches channel water away from mining sites before runoff reaches exposed
minerals while others in the diversion system direct contaminated water into holding ponds for
evaporation or treatment. Ditches are often constructed from soils and clays found in the area
surrounding a mine site. At some sites, ditches are constructed from concrete or mixtures of
natural and synthetic materials. Although these synthetic materials are more expensive, they
often do a more complete job of controlling runoff and process water. Drainage ditches are
typically constructed to handle a volume of water produced in heavy rains that may occur only
a few times a decade. In this way, overflow of contaminated water is minimal in all except the
most severe rainstorms.
Containment ponds and collection dams are used to hold contaminated water for
evaporation and treatment. Containment ponds are constructed of materials that prevent seepage
and leakage of contained water. Ponds may be simple constructions of clay or impermeable rock
built in natural drainage basins, or they may be complex, expensive structures built of cement
or synthetic material with liners and elaborate leakage monitoring systems. Generally, ponds
used to hold leaching solutions are more sophisticated than holding ponds for mine runoff
because of the valuable nature of the metal-rich solutions in leaching holding ponds.
Control of Groundwater
Water control systems at mine sites must also prevent the contamination of groundwater
sources. Groundwater pumping systems are used to control or reduce underground seepage of
contaminated water from collection ponds and waste piles. Wells are drilled where underground
water movement is detected, and pumps are then used to move the water out of the ground to
holding ponds and/or to a treatment plant. Subsurface drainage systems are also used to control
seepage in mining areas. These systems use a drain channel and wells to collect contaminated
water that has seeped underground and move it to a treatment plant. Subsurface drainage
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systems are often more cost-effective than pumping systems, but are practical only in situations
where the contaminated water has sunk to a depth typically less than 25 meters.
Subsurface barriers are used to divert groundwater away from mining operations. The
most common forms are slurry walls and grouting. Slurry walls are made of low-permeability
materials (concrete-bentonite mixtures) that are installed in the ground around mining operations.
Grouting involves the injection of a liquid solution (commonly cement) into rock crevices and
joints to reduce water flow. Both grouting and slurry walls are only effective up to depths of
around 20 meters.
Siting Waste Piles Away From Ground and Surface Water
In addition to controlling water flow, acid drainage minimization also requires that waste
and tailings dumps be properly designed and sited. When selecting a site for waste dumps, mine
operators should consider the topography of the site and the proximity to groundwater, streams,
and rivers. Dumps can be sloped to minimize uncontrolled runoff and to control the velocity
of water that flows into containment ponds. If rivers are nearby, the dump, containment ponds,
and surrounding diversion systems can be designed to channel water away from these protected
areas for control and treatment.
Monitoring of Acid Drainage
Monitoring provides information about the physical condition of the mine site and the
surrounding water quality. If properly performed, monitoring can furnish timely and accurate
information allowing regulators and mine operators to take necessary actions to avoid damaging
acid drainage situations.
Monitoring the Mining Site
Preventing acid rock drainage requires careful monitoring of waste rock dumps, ore
stockpiles and leaching sites. The stability of waste rock mounds is one important consideration.
Unstable piles can cause rocks to shift and roll away from the monitored confines of the mine
site. The large-scale movement of waste piles may change runoff channels and damage
diversion systems, increasing uncontrolled flows of contaminated water to ground and surface
water. A regular program of waste and tailings dump observation can detect unstable conditions
that can be corrected by regrading dumps with heavy machinery or repairing dump barriers and
ditches.
Water Quality Monitoring
A range of chemical, physical, and biological parameters can be used to evaluate water
quality, including: pH, metal content, aquatic toxicity testing using indicator species, and
temperature. Appropriate parameters are selected according to the characteristics of each mining
site. It is also important to select sampling sites that are near streams and lakes that receive
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runoff from waste piles. Monitoring is often performed on a regular basis so that changes in
contaminant levels can be detected quickly. If monitoring detects abnormal levels of
contamination, these sources can be traced and additional control measures imposed.
Treating Acid Drainage
The Conventional Approach
The conventional approach to treating contaminated water produced through acid drainage
involves an expensive, multi-step process that pumps polluted water to a treatment facility,
neutralizes the contaminants in the water, and turns these neutralized wastes into sludge for
disposal. The process is divided into the following steps:
• Equalization,
• Neutralization,
• Aeration,
• Sedimentation, and
• Sludge disposal.
The process is depicted in Figure 1. The first step in the process, equalization, involves
pumping polluted water into a holding basin. The holding basin may be the containment pond
at the base of the waste or tailings dump, or may be an additional basin constructed for this
purpose. A steady "equalized" flow of water is then pumped out of the holding basin to a
treatment plant for neutralization. Lime is commonly added to the water in the treatment plant
to neutralize the acid. The next step, aeration, involves moving the treated water to another
basin where it is exposed to air. This allows ferrous ions in the water to bind with the lime,
creating a solid. The solid then settles to the bottom of the pond as sediment. This sediment
contains most of the contaminants that had previously been mixed with the water. The
accumulated sludge at the bottom of the basin can then be removed for disposal.
Sludge disposal is the most expensive and difficult part of acid drainage treatment. The
easiest method for final disposal is to pump the sludge into abandoned mines. The long-term
environmental impact of this method is undetermined. While the mine is still active, the sludge
may be placed in a basin next to the sediment pond. The sludge is left in this second pond (also
called a sludge lagoon) until evaporation takes place and the sludge dries. The sludge can then
be transferred to an appropriate safe location for long term storage/or disposal.
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Conventional Approach to Acid Mine Drainage
Equalization
Mine Pump
Neutralization
Lime Additive
Holding Basin
Aeration
Settling Ponds
Mixer
Sedimentation
Sludge Requiring Disposal
Sludge disposal
Water Flow
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An Unconventional Approach-the Use of Wetlands
The long-term impact of highly acidic water containing metals upon wetland areas and
surrounding wildlife is well known and of concern. Wetlands serve as important wildlife habitat
and ecosystems as well as natural flood control in and of themselves. Man-made wetlands have
been used experimentally in some circumstances to treat acid drainage containing metals,
however, their use for this purpose remains controversial. In these cases, wetlands, areas
sometimes or always inundated with water, can serve as a passive system to filter polluted water.
They have been of interest in the control of acid drainage because they do not require the
addition of chemicals or the use of large-scale pumping of contaminated water. They rely on
natural processes to neutralize the contaminants in the polluted water, theoretically offering a
less costly method of treatment than conventional approaches. Naturally occurring microbes
may be able to cause oxidation and precipitation of ferrous ions in acidic water. Sludge then
settles to the bottom.
Despite some theories that this method might prove cost-effective, current research results
are inconclusive and raise questions particularly about residuals metals contamination and other
biological effects.
3.1.2 Water Contamination From Beneficiation
Leach sites have the potential to introduce highly concentrated levels of acids and heavy
metals into surrounding water sources. The leaching process mimics acid drainage although it
is conducted under much more aggressive conditions, using high concentrations of acid, base,
or cyanide to extract metals from ore. Since leaching produces large volumes of contaminated
water, it is crucial that leach dumps and associated holding/extraction areas be designed to limit
contamination. It is also critical that high standards of quality assurance and quality control be
applied throughout the construction process. Most of the environmental problems associated
with leaching are caused by leakage, spillage, or seepage of the leaching solution at various
stages of the process. Potential problems include:
• Seepage of solutions through soils and liners beneath leach piles;
• Leakage from solution-holding ponds and transfer channels;
• Spills from ruptured pipes and recovery equipment;
• Pond overflow caused by excessive runoff; and
• Ruptures of dams or liners in solution holding ponds.
Pollution Prevention: Minimizing Discharges from Leach Areas
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To prevent groundwater and surface water contamination caused by the leaching process,
governments can help mining companies set up properly-designed leaching sites by providing
technical assistance and/or guidelines. Governments may also wish to supplement these
guidelines with enforceable regulations to help bring companies into compliance. These
guidelines and regulations could encourage or require mining companies to do the following:
• Locate waste piles away from groundwater and surface water;
• Design leaching sites as self-contained systems that pump the leaching solution
back into the leaching pile;
• Line solution holding ponds with gunite (sprayed cement), clay, or synthetics, and
ditches with concrete using multiple liners with leak detection when appropriate;
• Apply high standards of quality assurance and quality control throughout the
construction process;
• Monitor the leach area closely in order to detect releases early; and
• Establish systems and procedures for spill control, clean-up and notifications,
should a release occur.
While some of these environmental controls involve additional costs to mine owners,
others can actually reduce mining costs. For example, improved holding pond liners that reduce
seepage of metal-bearing solution can increase the volume of minerals extracted. Improved
systems for recycling leaching solution can also decrease costs while minimizing the volume of
contaminants produced. On the other hand, locating leaching sites away from groundwater and
surface water may increase transportation costs.
3.1.3 Hydrologic Impact and Erosion 'of Sediment
In addition to water contamination resulting from acids and dissolved metals, mining
operations have other effects on water sources in the vicinity of mine sites. Changes to the
natural topography of the land surrounding the mine site can reduce the amount of precipitation
that seeps into aquifers and can increase runoff to streams and rivers, causing erosion problems.
This section addresses the effects of mining on groundwater levels as well as the impacts of
surface mining on the erosion of sediments.
Hydrologic Impact
Surface mining can increase or decrease the amount of runoff to streams around the
mining area. Increased surface runoff can reduce seepage to underground water sources, causing
groundwater levels to fall. Frequently too, mines must be continuously dewatered to allow
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required access to flooded ore bodies. This change in hydrology can lead to a temporary or
permanent loss of water in wells for several miles around the site. A reduction in groundwater
levels is a particularly sensitive problem in semiarid areas because of the importance of
groundwater as a source of drinking water for livestock and as an irrigation source for
agriculture.
It is necessary to determine the impact of mining on groundwater levels prior to
beginning mining operations. Hydrologic modeling in conjunction with mine site monitoring can
forecast hydrologic impacts. In addition, steps must be taken once operations begin to minimize
the harmful hydrologic impact of mines. There are, however, few specific remedies for
restoring groundwater to its original level. Wells can be drilled deeper to reach the reduced
groundwater levels or additional water can be transported to affected communities. In areas
where groundwater is crucial, the mining industry and regulators can work together to consider
how mine operators will address the potential future impacts of planned mining projects on
groundwater levels before mining operations begin.
Erosion of Sediment
Sediment is considered one of the world's principal pollutants. Sediment can contain
heavy metals and other toxic substances. Even when sediment is not toxic, it can cause severe
environmental damage by clogging reservoirs, increasing flood crests, and destroying crops.
It can also destroy habitat for fish and other aquatic life. Erosion and sedimentation are usually
gentle natural processes that occur over long periods of time, but surface mining can accelerate
this process by stripping away protective soil cover and changing the natural topology of the
land. A heavy rainstorm can move tons of soil at an exposed, poorly designed surface mine in
a brief period of time.
When designing a mine, it is important to consider the mine's potential impact on
erosion. Three key factors are land type, soil and rock types, and proximity of water sources
to the mine. Mine planners can consider ways to minimize damage to physical features critical
to the control of erosion and sedimentation. There are several steps that can be taken to
minimize erosion and sediment damage. Barriers made from natural or man-made materials,
such as hay bales and rip rap (rock facing), can be erected to control sediment runoff. These
barriers can be part of a general system to pool runoff into an impoundment area or can be built
specifically for at-risk sections of the mine site. Planting and cultivation of dense vegetative
covers of grass and weeds, shrubs, vines, or trees is often a very effective and inexpensive
method of preventing erosion on steep slopes and along drainage pathways.
In some instances, care in site selection and development can help minimize effects on
erosion and sedimentation with no added cost. The mine can be designed to minimize
disruptions to natural runoff paths. Often, mine operators try to limit development and building
construction near streams and rivers in order to maintain floodplains that naturally control water
flow. Ongoing monitoring and maintenance of natural and artificial erosion prevention structures
is necessary to ensure that sedimentation is adequately controlled.
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3.1.4 References for More Information on Water Pollution Prevention and Control
Mining-related water pollution is discussed extensively in many of the references detailed
at the end of this document. Especially useful is the EPA's Office of Solid Waste's series
Extraction and Beneficiation of Ores and Minerals. This series of reports includes information
on the gold, copper, lead, zinc, iron, uranium, and gold placer sectors. In addition, M.
Sengupta's Environmental Impacts of Mining (available from Lewis Publishers) discusses the use
of wetlands for the treatment of mine drainage. For specific information on the environmental
hazards of leaching, the National Technical Information Service document Copper Dump
Leaching and Management Practices that Minimize the Potential for Environmental Releases
comprehensively covers the water pollution controls for leaching operations in Copper mining.
The full references for these documents can be found in the Sources of Additional Information
section.
3.2 Air and Noise Pollution and Options for Prevention and Control
Although the most serious air pollution problems associated with the minerals industry
occur during smelting, substantial air pollution can also occur at mining sites during excavation
and transportation. In addition, the explosives used in mining operations represent an
environmental hazard that may impair the hearing of employees and surrounding residents, and
may damage natural formations and man-made structures in the vicinity of mining sites.
3.2.7 Dust
An important air pollution impact produced during mining is dust. Dust is created at all
stages of the mining process, including excavation, processing, and transportation. Dust clouds
may be carried far from the mine site depending on wind and other climatic conditions. As
such, the harmful effects of mine dust may impair the health of residents who live near mining
sites as well as that of mine employees.
Dust control methods at mine sites are aimed at reducing amounts and concentrations of
dust produced and minimizing human exposure to the dust remaining. The most important
element of dust control at underground mines is properly designed dust capture and removal
integrated into the ventilation system. Ventilation design is a highly specialized field and
ventilation engineers are often consulted during planning and evaluation of new sites. Water
sprays are also widely used in processes such as the transportation of material and the crushing
of ore. These sprays can greatly reduce the level of dust at the site. Surface stabilization of
solid piles or tailing areas which can easily become airborne in windy dry conditions can be
controlled by applying dust suppressant agents such as lignin sulfonates, magnesium chloride and
other compounds if circumstances and use will not adversely affect nearby plants and aquatic
life from runoff into streams.
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3.2.2 Fumes and Exhaust
Despite the best attempts to control dust, there are areas in any mining operation where
workers may be exposed to elevated dust concentrations. For these areas, it is important that
a respirator program is in effect, including a provision for periodic fit testing. Modern mining
techniques require the use of a variety of hazardous chemicals such as acids, mercury, and
cyanide for ore processing. In addition, heavy machinery and explosives used throughout the
excavation process produce harmful exhausts and gases. This section briefly describes the
potential effects of these hazards on employees and provides recommendations for their control.
A serious hazard at underground mining operations results from exhaust gases released
by diesel engines and fumes produced during blasting. These exhausts produce carbon monoxide
and nitrogen oxide gas that can collect in underground cavities. Workers exposed to high
concentrations of these gases risk serious illness and death. The design of proper ventilation
systems at underground mining areas is therefore critical. Ventilation system plans are often
reviewed by qualified experts before mine operations begin.
It is also important to carefully and continuously monitor levels of carbon monoxide and
nitrogen oxide gas in active underground mines. Gas levels can be monitored with direct-
reading devices containing built-in alarms. If gas concentrations approach dangerous levels, the
alarms can signal workers to evacuate the area. Process controls and alarms on key variables
such as pH and temperature are also commonly used to prevent releases of hazardous chemicals.
3.2.3 Noise
Explosives and heavy machinery are used regularly at mining sites, resulting in
potentially harmful amounts of noise pollution. Miners subject to high noise levels for extended
periods of time may become permanently deaf. The European Community has set limits for
daily exposure at 85 decibels with no peak sounds above 140 decibels. Noise levels can be
monitored and steps taken to reduce volumes where appropriate. Ear plugs or other noise-
dampening devices may be appropriate for employees in some cases.
3.2.4 Blasting
The use of explosives for excavation is common in surface mining. Control of
vibrational damage to natural formations is therefore an important environmental consideration.
Damage to natural formations has been observed up to 500 meters away from blasting sites.
Many mines limit the number of explosions, using millisecond delays between blasts to minimize
concussion and noise, especially near population centers, natural scenic formations, wells, and
stream channels.
Several states in the United States have established guidelines for preventing or
minimizing vibrational damage. Listed below is a table established by the U.S. state of West
Virginia for safe blasting distances.
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Distance to Nearest Residence
Building or Other Structure (meters) Max. Explosive Charge (kg)
30 2
150 45
300 180
460 410
610 730
760 1140
910 1630
1060 2220
1220 2900
1370 3670
1520 4530
5.2.5 References for More Information on Air and Noise Pollution and Prevention
Options
EPA's Office of Solid Waste's series on mining and the United Nations Environment
Programme (UNEP) publication are both good sources for information on air pollution from
mining dust. In addition, more detailed information about worker health effects from dust and
noise exposure as well as other hazardous working conditions can be obtained by contacting the
United States Occupational Safety and Health Administration (OSHA) in Washington D.C., the
World Health Organization (WHO) in Geneva, or the International Labor Organization (ILO).
3.3 Environmental Impacts of Non-Modern and Small-Scale Mining Methods
Many of the environmental problems discussed above are common to medium and large
scale mining operations using modem techniques. In many countries, however, small mining
ventures using non-modern methods employ large numbers of people and have large cumulative
effects on human health and the environment. In addition, mines in some countries employ
traditional labor-intensive methods on a large scale. This section describes non-modern and
small-scale mining, especially gold-mining, and its associated environmental problems. In
addition, measures that governments can take to lessen the environmental impact of these mining
operations are presented.
"Non-modern mining" refers to mining ventures that use hand tools and primitive
extraction methods instead of heavy machinery and complex chemical purification technologies.
These operations can be very large and well organized, as in the copper extraction industry in
Peru. "Small-scale Mining" refers to these non-modern methods performed by collections of
individual miners. In contrast to industrial mining, which is typically performed by large
companies, small-scale mining is generally undertaken by individual prospectors with limited
resources. Small-scale mining for gold takes place in many developing countries, including the
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Philippines, Brazil, Venezuela, and many countries in West and Central Africa. Historically,
such small-scale gold mining has occurred in the context of a "gold rush" that brings large
numbers of people to a previously rural area.
Non-modern mining has three principal environmental impacts. First, rural areas where
mining occurs often lack roads, sewage and water systems, and health services to handle the
population increase caused by a "gold rush" or by a rapid increase in employment opportunities
at a company mine. This lack of services can lead to both public health and environmental
problems. For example, the lack of proper wastewater facilities can lead to the pollution of
surrounding ground and surface water, poisoning water supplies and endangering local flora and
fauna. Second, the primitive equipment, methods, and conditions of non-modern mining can
be hazardous to miners' health. Miners can poison themselves through improper use of toxic
chemicals, such as mercury and cyanide, or develop chronic lung difficulties from dust in the
mining environment. Third, when mining activity ceases, prospectors do not have the resources
to restore excavated land to its prior state. For example, in Brazil, small-scale gold mining has
caused deforestation of the rainforest.
Many developing nations regard small-scale mining as an opportunity for economic
advancement of their citizens, and see these small ventures as a more equitable way of sharing
a country's natural resources. In addition, companies that adopt non-modern methods can
employ significant numbers of workers. Some nations are therefore reluctant to impose strict
controls on small-scale and non-modern mining activity. In addition, small-scale miners are
typically a migrant population, and are more difficult to regulate than large companies.
Governments that want to reduce the environmental impacts of small-scale and non-modern
mining, without eliminating the practice entirely, could consider the following actions:
• Provide technical assistance to small-scale miners to encourage environmentally-
sound mining practices;
• Build appropriate infrastructure in rural areas to handle the influx of miners; and
• Enact laws that restrict non-modern mining practices that damage the
environment.
3.3.1 References for More Information on Non-Modern and Small-Scale Mining
The United Nations Environment Program document, Environmental Aspects of Selected
Non-Ferrous Metals Ore Mining, discusses small-scale gold mining issues.
3.4 Mine Closure
When a mine closes, measures are often taken to minimize the future environmental
impact of the abandoned mine site, as well as to ensure the safety of surrounding residents.
Often efforts are made to make the mined land resemble pre-mining topography, approximate
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original soil material, and to reestablish the same or similar vegetative cover. Reclamation
activity is often aimed at establishing a permanently-stable landscape that is environmentally
compatible with the surrounding ecosystem.
Mine closure typically involves securing waste and tailings dumps, covering or "capping"
mine pits and leach areas, and reclaiming and revegetating the land disturbed during mine
operations. Often these closure activities are less expensive and more effective if they are
planned for early in the life of a mine site. Many governments therefore require that plans for
mine closure be included in an Environmental Impact Assessment developed before operations
begin. Governments and regulatory agencies also normally require that mining operators post
bonds or provide other financial assurances to cover all closure activities in case of default.
Mining operations where acid drainage is a problem or where leaching is used are of
particular concern. Often acid drainage at these abandoned sites continues for many years after
operations cease, causing serious water contamination. Cover systems for mine pits and leach
areas are often used to minimize these lingering effects. Cover systems generally include some
type of mine or leach area cap overlaid with a material capable of supporting vegetation.
Sometimes the installation of a cover system is preceded by the detoxicification of leached ore
piles to insure that residual toxic chemicals are properly neutralized. Capping entails the
placement of a layer of material composed of natural soils and rock, clays, and/or synthetic
liners over the leach pile or mine pit. Multilayered caps consisting of a layer supporting plant
growth, a layer of loose soil that allows drainage, and a low-permeability layer that prevents
exposure of mine rock are the most common. Capped soils may also be treated with lime or
other chemicals to reduce the toxicity of the underlying waste pile. In addition, runoff from
sites can still be monitored, and contaminated water can be treated, using the techniques
described in the acid drainage section above.
After the mine pit and leach area are capped, the mine area can be reclaimed through
restoration of the pre-mining topography and revegetation of the land. In many instances, leach
and waste dumps have modified the land to such an extent that efforts at total reconstruction of
pre-mining land shapes is impossible or prohibitively expensive. Nevertheless, trucks, shovels,
and draglines used for waste hauling during active operations can be employed to construct
roughly similar landscapes once operations are complete. Since dumping activity occurs
throughout the active life of the mine, desired post-closure topography must be planned into the
design of waste dumps and leach areas. Closure activity can then focus on refining these
landscapes by trimming dump piles and preparing the ground for revegetation.
Revegetation minimizes erosion at closed mining sites, reduces wind-blown dust, absorbs
contaminants harmful to humans, and helps reestablish natural ecosystems in the surrounding
area. The ability of post-mining land to support plant life is determined by the properties of the
soil in the area where plants lay down their roots, the seed mix, and the local climatology.
Particularly important is the location of the mine since arid locations and those at high altitudes
with short growing seasons represent extreme challenges to revegetation. Efforts are made to
grade for minimum slope requirements and replace soil that approximates the pre-mining
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chemical and physical properties of the original soil. Often the most cost-efficient way to resoil
is to save the soil from the area originally excavated. In instances where this is not possible,
however, soil can be taken from the surrounding area or brought to the mining site expressly
for revegetation.
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4. PLANNING, MONITORING, ENFORCEMENT AND COMPLIANCE
APPROACHES
Although there are a variety of approaches to managing mining-related environmental
problems, a comprehensive program is often the most successful and cost effective. A
successful program generally establishes environmental objectives through clearly defined
requirements, sets voluntary goals on liabilities, balances planning, permitting, monitoring,
enforcement, and builds compliance through education and cooperation between industry,
government, and the surrounding community. The following are characteristics of effective
mining environmental management programs in some countries:
• Environmental management is given a high priority during the planning,
licensing, and development of mining operations.
• Environmental accountability within industry and government rests with high
levels of management and policy-makers.
• Employees at all levels have an individual responsibility for environmental
management. Mine management ensures that adequate resources, staff, and
training are available to implement environmental plans.
• Industry and government involve the local community and other directly
interested parties in the environmental aspects of all phases of mining activities.
• Environmentally sound mining technologies and practices are adopted in all
phases of mining activities. Best management practices are adopted to minimize
environmental degradation.
It is important to emphasize that many of the environmental control technologies and
recommendations discussed in the previous section require careful planning early in the mining
process. They also need to be re-examined throughout the life of the mine as conditions change
and initial assumptions need to be modified. Ventilation systems that minimize hazards to
workers, diversion ditches and containment ponds that limit contamination of streams and rivers,
and well-designed properly installed leach areas that reduce the potential for major contaminant
releases all must be planned before operations begin if serious problems are to be avoided. In
addition, ongoing monitoring is required to detect changes in the environment that pinpoint
inadequacies of current controls or identify the need for maintenance. Finally, adequate
attention to preparing a mine site for closure is necessary if acid drainage is to be minimized
once a mine site is no longer active.
Environmental impacts are minimized when environmental considerations are an integral
component of mining operations, from the planning stages through closure. This section
considers a general approach for integrating environmental concerns into every stage of the
mining process.
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4.1 Using Environmental Impact Assessments During Planning
To bring environmental concerns into the initial stages of mining projects, governments
and industry often use Environmental Impact Assessments (EIAs) when projects are first
proposed. An EIA examines the potential environmental impacts of a project, and outlines ways
in which these impacts can be avoided or mitigated through better project design. The EIA is
a cyclical planning process involving government, industry, and involved citizens, that requires
examination, review, and reformulation of project design until an approach acceptable to
industry and regulators can be developed. EIAs typically address several key areas, including:
• identification - what will be the direct and indirect impacts of the project on the
environment? what regulations apply?
• prediction - what will be the extent of the changes?
• evaluation - will the changes be significant? and
• mitigation — what can be done to avoid or reduce the impact?
EIAs address the entire lifespan of a mining operation, including measures for
revegetation and closure. They are designed to address all of the major environmental issues
associated with mining operations so that expected environmental impacts, planned control
measures, and methods of monitoring are clear to governments and mining operators.
A suggested outline for an environmental assessment is included in the appendices at the
end of this document. EPA's Office of Solid Waste, in cooperation with the Office of Federal
Activities, prepared an EIA technical document and checklist to assist those reviewing EIA on
mining projects. Excerpts are included in Appendix 3 which highlight the general environmental
questions that should be raised and addressed to fully understand the environmental effects of
any proposed mining project.
4.2 Monitoring Active Mines
Monitoring allows government regulators and mining operators to observe a mine's
impact on the surrounding environment and to take steps to minimize that impact. Monitoring
in and around a mine site is necessary to characterize baseline conditions and to identify changes
in conditions during active mining and after mining has taken place. The information is used
to identify unanticipated environmental effects, as well as to locate routine repair and
maintenance needs. Monitoring provides input to decisions on appropriate mitigation and
reclamation strategies. In addition, monitoring can indicate the loss of raw and refined material,
and identify general operational inefficiencies that affect mine profitability.
Environmental conditions that are typically monitored include physical processes such as
water flow, and chemical characteristics such as water quality. Health and safety measures, such
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as air quality of underground operations, medical monitoring, dust concentrations and stability
of stored hazardous chemical are also subject to regular monitoring. Changes in fish and plant
populations are also observed to measure the impact of contaminants on the surrounding
environment. The frequency and complexity of monitoring activity must strike a balance
between the expense of monitoring operations and the cost savings associated with early
detection of environmental damage.
4.3 Establishing Technical and Performance Standards and Permitting the Mining
Industry
In most countries, mining, like other industrial activity, is subject to laws, regulations,
and standards in many areas of operation. Environmental requirements such as waste disposal
and control of water contamination are sometimes incorporated into these laws. Although
mining laws are rarely specific and extensive enough to be considered a complete environmental
control program, they often draw upon laws in related areas (e.g. general environmental
legislation, and/or legislation on health, safety, and chemicals) to provide a legal framework for
environmental protection. Some environmental issues that mining laws can incorporate into
specific regulations or individual permits/licenses include:
• Mine worker exposure limits and monitoring requirements;
• Establishment of wastewater retention and treatment techniques, and safe
management of contaminated runoff;
• Soil erosion control and revegetation procedures during operation and after
closure;
• Numerical limits for discharges;
• A requirement to prepare plans for solid waste and soil disposal prior to approval
of operations including financial assurances such as bonding for all closure
requirements.
• Mandatory reclamation, bonding, and/or restoration of sites and disturbed areas,
and removal of all unused structures and machinery; and
In addition, related legislation may cover aspects of environmental regulation of direct
concern to the mining industry, including:
• Laws governing land use and the impact of development on endangered species,
tropical forests, and flora and fauna;
• Laws governing the impact of development on indigenous cultures;
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• Water quality laws that limit discharges into streams or rivers;
• Proper transport, storage, handling, and disposal of chemicals.
• "Clean Air" laws that govern emissions of toxins in gases or dust; and
• Controls for soil contamination by wastes and chemicals.
These environmental regulations can be packaged in a number of ways, depending
in part on the existence of an environmental legal framework apart from laws governing
mining. New laws can be drafted to build on, and be consistent with the existing legal
structure. The appendix at the end of this document shows excerpts from environmental
mining laws and regulations in the United States and Bolivia. These are intended to serve
as examples and are not presented as the only or best responses to the environmental
problems associated with mining activities in other countries or regions.
4.4 Compliance Monitoring and Enforcement Programs
This Document is intended to accompany the Principles of Environmental
Enforcement Text, U.S. EPA, which describes the basic elements and approaches for
establishing effective compliance strategies and enforcement programs. As a supplement
to international efforts to advance effective environmental compliance and enforcement
programs, the readers are referred as well to the UNEP IE training manual on Institution
Building for Industrial Compliance and Proceedings of the series of International
Conferences on Environmental Compliance and Enforcement for further discussion.
4.5 Mining Associations and General Sources of Information
Additional information on mining and the environment can be found through:
The American Mining Congress, 1920 N St., Suite 300, Washington D.C. 20036
Tel:(202)-861-2800
California Mining Association, 1 Capitol Mall, Suite 220, Sacramento, CA 95814
Tel (916)447-1977, Fax: (916) 447-0348
Colorado Mining Association, 1600 Broadway, Suite 1340, Denver, CO 80202
Tel: (303) 894-0536, Fax: (303) 894-8416
Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401
Tel: (303) 273-3000, Fax: (303) 273-3278
The International Council on Metals and the Environment, 360 Albert St., Ottawa, Ontario,
Canada, K1R7X7
Tel: (613)-235-4263
Environment-Neutral Drainage Program, 555 Booth Street, Ottowa, Ontario, K1AOG1
Tel: (613) 995-4681
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5. APPENDICES
5.1 APPENDIX 1: Sample Environmental Regulations
5.1.1 Sample Outline of An Environmental Assessment Report
Environmental assessment reports are usually concise, limited to significant environmental
issues, and aimed at project designers, and project decision-makers. The level of detail
corresponds to the degree of potential impacts. The report often includes the following sections:
1. Executive summary: A summary of significant findings and recommended actions.
2. Environmental regulations: The policy, legal, and administrative framework related to the project. This
is especially important in the case of co-financed projects when the requirement of many organizations must
be accommodated.
3. Project description: A detailed description of the project, including its technical, geographic, ecological,
economic, and social context. Include any off-site investments required as part of the project, for example,
pipelines, roads, power plants, water supply, housing, storage facilities.
4. Baseline data: The study area's dimensions and a description of relevant physical, biological, and socio-
economic conditions, including any changes anticipated before the project commences.
5. Analysis of alternatives: Alternatives to the proposed project, including the "no action" option. This
section examines the potential environmental impacts, capital and recurrent costs, institutional capacities,
training, and monitoring requirements for all design, site, technology, and operational alternatives.
6. Environmental impacts: The positive and negative impacts likely to result from the proposed project, and
comparison with alternatives. This section reviews the extent and quality of available data, identifies key
gaps in data, estimates uncertainties associated with predictions, and specifies topics that do not require
further attention.
7. Mitigation plan: Feasible, cost-effective mitigation measures that may reduce adverse impacts on the
environment to acceptable levels. The plan can consider compensatory measures if mitigation cannot be
implemented effectively.
8. Monitoring plan: This section recommends a monitoring plan, including implementation by a designated
monitoring agency or individual, cost estimates and other pertinent information such as training.
9. Appendices:
• Personnel and organizations involved in the environmental assessment.
• Persons and organizations contacted, including addresses and telephone numbers.
• References to all written materials used in study preparation. This is especially important given
the large amount of unpublished documentation often used.
• Record of interagency/forum meetings. This includes lists of both those invited and those that
actually attended, as well as a summary of the discussions.
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5.7.2 Excerpts from the Bolivian Mining Code
Article 70
The tapping of mineral resources shall take account of integrated raw material management, the processing
of waste material, the safe disposal of tailings, waste and clearance materials, efficient energy use and rational
deposit management.
Article 71
Mining operations shall, both during and on completion, make provision for recovery of the areas mined
so as to reduce and control erosion, stabilize the land and protect water resources, streams and hot springs.
Article 72
The Ministry of Mining and Metallurgy shall, in coordination with the National Secretariat for the
Environment, establish appropriate technical standards in order to set permissible limits for the various actions and
effects relating to mining activities.
Article 92
Any individual or group shall have a right to participate in environmental management, in accordance with
the provisions of this Law, and shall have a duty to play an active role in the community in the defense and/or
conservation of the environment and, if necessary, to utilize the rights conferred on them by this Law.
Article 105
Any environmental crime is committed by anyone that violates paragraphs (2) and (7) of Article 216 of the
Criminal Code and specifically when someone:
(a) poisons, contaminates or adulterates water intended for public consumption, for use in industrial
agriculture or fisheries, to levels above the permissible limits to be established in respective
regulations;
(b) violates livestock health standards or spreads epizootic diseases or crop pests.
Such crimes shall be subject to one to ten years imprisonment.
Article 107
Anyone that dumps or discharges untreated wastewater, chemical or biochemical liquids, objects and any
kind of wastes into/on to watersheds, shores/beaches, aquifers, river basins, rivers, lakes, lagoons or ponds, that
are capable of polluting or degrading the water and exceed the limits to be established in the respective regulations,
shall be subject to one to four years' imprisonment and a fine of 100 percent of the damage caused.
Article 112
Anyone that stores, dumps or markets industrial wastes in liquid, solid or gaseous form that endanger
human life and/or cannot be assimilated by the environment, or that do not comply with health and environmental
protection standards, shall be subject to up to two years' imprisonment.
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5.1.3
Excerpts from United States EPA Regulations
§ 440.102 Effluent limitations representing the degree of effluent reduction attainable by the application of the best
practicable control technology (BPT).
Except as provided in Subpart L of this part and 40 CFR 125.30 through 125.32, any existing point source subject
to this subpart must achieve the following effluent limitations representing the degree of effluent reduction attainable
by the application of the best practicable control technology currently available (BPT):
(a) The concentration of pollutants discharged in mine drainage from mines operated to obtain copper bearing ores,
lead bearing ores, zinc bearing ores, gold bearing ores, or silver bearing ores, or any combination of these ores in
open-pit or underground operations other than placer deposits shall not exceed:
Effluent characteristic
Maximum for any 1 day
Average of daily values
for 30 consecutive days
Milligrams per liter
TSS
Cu
Zn
Pb
Hg
Ph
30
30
15
6
002
(*)
20
15
75
3
001
(*)
*Within the range 6.0 to 9.0
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(b) The concentration of pollutants discharged from mills which employ the froth flotation process alone or in
conjunction with other processes, for the beneficiation of copper ores, lead ores, zinc ores, gold ores, or silver ores,
or any combination of these ores shall not exceed:
Effluent characteristic
Maximum for any 1 day
Average of daily values
for 30 consecutive days
Milligrams per liter
TSS
Cu
Zn
Pb
Hg
Cd
Ph
30
30
10
6
002
10
20
15
5
3
001
05
(*)
*Within the range 6.0 to 9.0
(c) (1) Except as provided in paragraph (c) of this section, there shall be no discharge of process wastewater to
navigable water from mines and mills which employ dump, heap, in situ leach or vat leach processes for the
extraction of copper from ores or ore waste materials. The Agency recognizes that the elimination of the discharge
of pollutants to navigable waters may result in an increase in discharges of some pollutants to other media. The
Agency has considered these impacts and has addressed them in preamble published on December 3, 1982.
(2) In the event that the annual precipitation falling on the treatment facility and the drainage area contributing
surface runoff to the treatment facility exceeds the annual evaporation a volume of water equivalent to the difference
between annual precipitation falling on the treatment facility and the drainage area contributing surface runoff to
the treatment facility and annual evaporation may be discharged subject to the limitations set forth in paragraph (a)
of this section.
(d) (1) Except as provided in paragraph (d) of this section, there shall be no discharge of process wastewater to
navigable waters fronrmills which extract gold or silver by use of the cyanidation process. The Agency recognizes
that the elimination of the discharge of pollutants to other media. The Agency has considered these impacts and
has addressed them in the preamble published on December 3,1982.
(2) In the event that the annual precipitation falling on the treatment facility exceeds the annual evaporation, a
volume of water equivalent to the difference between annual precipitation falling on the treatment facility and the
drainage area contributing surface runoff to the treatment facility and annual evaporation may be discharged subject
to the limitations set forth in paragraph (a) of this section.
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(e) The concentration of pollutants discharged in mine drainage from mines producing 5,000 metric tons (5,512
short tons) or more of molybdenum bearing ores per year shall not exceed:
Effluent characteristic
Maximum for any 1 day
Average of daily values
for 30 consecutive days
Milligrams per liter
TSS
Cd
Cu
Zn
Pb
As
Ph
30
10
3
10
6
10
20
05
15
5
3
5
(*)
*Within the range 6.0 to 9.0
(f) The concentration of pollutants discharged in mine drainage from mines producing less than 5,000 metric tons
(5,512 short tons) or discharged from mills processing less than 5,000 metric tons (5,512 short tons) of molybdenum
ores per year by methods other than ore leaching shall not exceed:
Effluent characteristic
TSS
Ph
.
Maximum for
Effluent limitations
any 1 day
Average of daily values
for 30 consecutive days
Milligrams per liter
50
(*)
30
(*)
*Within the range 6.0 to 9.0
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(g) The concentration of pollutants discharged from mills processing 5,000 metric tons (5,512 short tons) or more
molybdenum ores per year by purely physical methods including ore crushing, washing, jigging, heavy media
separation shall not exceed:
Effluent characteristic
Maximum for any 1 day
Average of daily values
for 30 consecutive days
Milligrams per liter
TSS
Cd
Cu
Zn
As
PH
50
10
30
10
10
(*)
30
05
15
5
5
(*)
*Within the range 6.0 to 9.0
(h) The concentration of pollutants discharged from mills processing 5,000 metric tons (5,512 short tons) or more
molybdenum ores per year by froth flotation methods shall not exceed:
Einuem cnaraciensuc
TSS
Cd " .
Cu
Zn
As
oH
Maximum for any 1 day
Average of daily values
for 30 consecutive days
Milligrams per liter
30
10
30
1.0
1.0
(*)
20
05
15
5
5
(*)
*Within the range 6.0 to 9.0
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5.2 APPENDIX 2: Sample Cost Estimates
Listed below are cost estimates for several key environmental control mechanisms. These
are drawn from examples in the U.S. from Copper Dump Leaching and Management Practices
That Minimize The Potential For Environmental Releases, published by the U.S. Department
of Commerce, National Technical Information Services. The report was published in 1988.
These figures give a rough approximation of the costs for environmental safeguards.
Obviously costs will vary widely according to local conditions.
Table 1: 1986 Liner Installation Costs
Liner Type Installed Cost, $/m3
Soil-bentonite i.90
Soil Cement 3.30
(15 cm thick and sealer)
Asphalt-concrete 7.30-10.2
(10 cm thick, hot mix)
Chlorinated polyethylene 7.4-12.7
(CPE)
High-density polyethylene 8.6
(HDPE) (60 mil)
Table 2: 1986 Costs for Establishing Surface Water Controls
Operation Output Unit Cost, $
General Excavation
Front-end Loader 35-40 m3/h " 0.8-1.4/m3
Bulldozer 40-120 m3/h 1.2-1.1/m3
Ditch excavation
0.9 m deep 75-100 m/day 4.78-7.00/m
1.2m deep 50-70 m/day 6.8-10.20/m
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Building embankments;
spreading, shaping,
compacting
0.55-1.1/m3
Material delivered by
scraper: — 1.10-1.70/m3
Material delivered by
backdump:
Ditch Stabilization
Riprap 47 nWday 21.7-25.8/m3
Gunite (with 5-cm mesh,
2.5 cm thick)
Hauling, spreading gravel 790 mVday 7.00-8.00/m3
Table 3: Typical Costs for Capping and Revegetation
Material Available on Site
Excavation
Loading
Hauling
Spreading and Compacting
Material purchased off site
Purchase
Transportation
Spreading
Clay
1.86
1.58
13.39
12.52
10.90
7.35
2.52
Sand
1.00
0.84
3.39
0.55
7.88
7.35
Soil
1.17
0.98
3.39
2.52
13.70
7.35
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5.3 APPENDIX 3: Checklist for Environmental Impact Assessments of Proposed Mining
Projects
The following is an excerpt from the U.S. EPA Publication: TECHNICAL DOCUMENT -
Background for NEPA Reviewers: Non-Coal Mining Operations, December 1994, U.S.
Environmental Protection Agency, Office of Solid Waste, Special Waste Branch, December 1994.
It summarizes the general environmental questions that should be raised and addressed to fully
understand the environmental effects of any proposed mining project.
SUMMARY OF QUESTIONS THAT SHOULD BE ASKED WHEN REVDZWING
NEPA DOCUMENTATION
The following are questions that may be appropriate to ask about mining operations when
reviewing NEPA documentation:
General Questions Applicable to Most Mining Operations
• Has the local geology been defined, including all stratigraphic layers to be
encountered in mining?
• Has baseline data been collected to establish the surface water flow rates
(including seasonal variability) and water quality (including sediments) prior to
disturbance? Has the physical condition of streams within the project area been
determined? Has aquatic life been adequately characterized? What are the
designated and actual uses of surface water in the project area and downstream?
• What is the overall water balance for the facility? Have all potential discharges
to groundwater and surface water been anticipated and described (and controls
provided, as appropriate)? Does the applicant intend to obtain all necessary
NPDES permits? Can the facility ensure compliance with applicable water
quality standards?
• Has the hydrogeology of the site been mapped/clearly delineated? Has baseline
groundwater quality been determined? What are the designated and actual uses
of groundwater? What are the locations of all wells in the area and what are their
uses?
• Has the erosion potential been quantified? Have the appropriate runoff models
been used? Are the assumptions defined and justified? Have the potential
impacts on surface water been determined? Wherever possible, has model data
been validated by comparison to actual field data? What runon and runoff control
measures, including BMPs, will be used? Will they be maintained during active
operations and afterward?
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• Have baseline studies been conducted to characterize aquatic and terrestrial
life/habitats prior to mining/disturbance? Are there any threatened, endangered,
or rare species and/or critical habitats in the area? Have the requirements of the
Endangered Species Act been followed? What measures will be taken to protect
wildlife/habitat, including siting?
• Will any disturbance impact wetlands? If yes, what mitigation measures will be
taken? If jurisdictional wetlands are impacted, have CWA §404(b) requirements
been followed?
• Are the cumulative impacts over the life of the mine (including possible
expansions) described?
• Is public access to the site controlled? Is wildlife access to the site controlled?
Is the control described?
• Have the pre- and post-mining land uses been compared?
• What wastes will be generated? In what volumes? What are the expected
compositions of waste materials? What management practices will be used? Do
waste/materials management units have liners? Will adequate surface preparation
be performed prior to liner installation? Do units have drainage collection
systems? Leak detection systems?
• Have leachability tests been performed on wastes (for metals, sulfates, and other
potential pollutants)? Have radionuclide levels been determined, (where
appropriate)? If there is sulfide mineralization, has ARD/AMD testing been
conducted? Is there a plan to continue waste characterization/acid generation
testing during operations?
• Where wastes can generate ARD, what measures will be used to minimize acid
generation and/or provide treatment prior to discharge? Are mitigation measures
for ARD/AMD based on proven technologies (e.g., conventional treatment),
state-of-the-art technologies, or passive treatment practices (e.g., wetlands)? If
unproven methods are to be used, how will performance be monitored and have
contingencies been provided for?
• Is there a multi-media monitoring program (including surface and groundwater,
sediments, and air)? Are proposed parameters representative of likely discharges?
Where and how often will monitoring occur? Do monitoring frequencies account
for seasonal/operational variability? If impacts are detected, what actions will be
taken? How and to whom will data be reported?
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• Is there a spill prevention and response plan? Does it address all areas where
spills are likely to occur? Is secondary containment provided for storage areas
and pipelines?
• Is there a reclamation/closure plan? Will concurrent reclamation be performed?
Have proposed revegetation procedures been successfully used in the area
previously? Has long-term mine water management been addressed? After
closure, will drainage systems/discharges continue to be
monitored/maintained/addressed?
• Has the baseline air quality been determined? How will air emissions be
minimized? Have stack and fugitive emissions been
characterized/predicted/modelled? What technologies will be used to control such
emissions? How will any air pollution control wastes be managed? Does the
project plan ensure compliance with Federal and State CAA requirements? Has
the baseline meteorology for the area been adequately characterized and data
made available?
Mine Workings
• Is groundwater pumped to control water inflow into the mine workings/pit? At
what rate is the water pumped? Have the extent of aquifer drawdown and the
subsequent impacts been described?
• Are all aquifers and surface waters that might be impacted identified and included
in a monitoring plan? Are groundwater discharge areas (wetlands, ponds, lakes,
streams, seeps, etc.) included in a monitoring plan? Does the monitoring plan
account for seasonal variances? If an impact is suspected, what responses are
proposed?
• What are the consequences when mining and water withdrawal cease and the
pit/mine workings are subsequently flooded? What action will be taken once
mining stops and pumping is no longer employed to dewater the workings?
• Have the characteristics of the mine water been determined, including AMD?
Will collection and treatment be provided, as appropriate?
Waste Rock/Overburden
• How much overburden, waste rock, and ore will be excavated and stored or
disposed of? Are planned management units described fully?
• Have leaching characteristics of waste rock/overburden been determined
(including ARD)? How often during mining will leaching characteristics be
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evaluated? What measures are proposed to ensure protection of groundwater and
surface water from constituents leaching from waste rock dumps or overburden
piles?
Has the stability of waste management units/impoundments been determined? Did
the analysis consider any seismic risk? Will adequate drainage of berms be
provided? How will stability be measured during and after active operations?
Is closure and reclamation of these waste rock/overburden described in detail?
Is recontouring of the piles to stable slopes required? Will concurrent reclamation
be conducted, if appropriate?
Tailings Impoundments
What are the constituents in the tailings? What type of sampling was conducted
and was it representative? Have leaching characteristics of tailings been
determined? If so, what methods were employed? How often will sampling and
characterization be conducted during operation? Have reagents used during
beneficiation been addressed in the constituent analysis? What measures are
proposed to ensure protection of groundwater from constituents leaching from
tailings impoundments?
What other wastes does the operator dispose of in the tailings pond or tailings
area? How are these materials managed as wastes?
Does the project plan provide for maximum possible water reclaim/re-use? Have
all potential source reduction/recycling opportunities been identified and
reviewed?
Has adequate precipitation and snow melt data been compiled? Have all
collection/containment and treatment systems been properly designed to manage
up to a specific storm event and snow melt contributions (i.e., are they
appropriate for the predicted water balance)?
What analysis was conducted to determine stability of any structures (i.e., dams
or berms) associated with the tailings pile or pond? Did the analysis consider
snow melt contributions? Did the analysis consider seismic risk? Does the
document contain detailed drawings so that structural stability can be determined?
Have runon, runoff and unit capacity been evaluated? Have these evaluations
considered storm water and annual snow melt?
Does the plan provide for maximum recycling/reuse of pond water? Is there a
surface water discharge? What are the expected flow rates and discharge
characteristics? Has adequate treatment been provided, if necessary?
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• Is the closure and reclamation of the tailings ponds described in detail? What
steps constitute closure? Is recontouring of the pond required? Is a cap
proposed?
Copper Dump Leach Operations and SX/EW Plants
• What is the planned design of the dumps? How much material will be leached?
How will solution be applied? Has the stability of been determined? How will
stability be measured during and after active operations?
• What are the characteristics of dump materials, including ARD potential? What
type of sampling/testing was conducted and was it representative? What
analytical method was used to determine the constituents and what were the
results? Are there any other wastes generated (e.g., bleed streams)? What are
their characteristics and how will they be managed?
• Is the leaching process a closed loop system (e.g., is all solution collected)?
What will the water balance be after leaching ceases? Have the capacities of the
solution transport ditches and collection ponds been evaluated considering process
solutions and runoff/snow melt contributions? Are solution ditches and ponds
lined/double-lined? Is there a leak detection/collection system?
• How will reagents be transported/stored? Is there secondary containment/leak
detection? Is there a spill prevention and response plan?
• How will the dump affect ground and surface water quality during leaching
operations and after closure? Will monitoring be performed? Where, when, and
for which parameters?
• Will the dump be operated on a seasonal basis? Are temporary closure
procedures proposed? Will the dump be. monitored on a regular basis during the
inactive season?
• What is the proposed closure/reclamation plan? Will concurrent reclamation be
conducted, if appropriate?
Cyanide Leaching Operations
• Are the heap leach pad and process ponds lined appropriately? Is a leak detection
system in place and operational? Is an adequate monitoring plan proposed? What
triggers (chemical constituents) are to be employed within the monitoring plan to
signify the possibility of a leak? What are the proposed contingency plans in the
event a leak is detected?
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• Has the stability of heaps/spent ore management units/impoundments been
determined? Did the analysis consider any seismic risk? How will stability be
measured during and after active operations?
• Has adequate precipitation and snow melt data been compiled? Have all
collection/containment and treatment systems been properly designed to manage
up to a specific storm event and snow melt contributions (i.e., are they
appropriate for the predicted water balance)?
• Are the closure of heaps described in detail? What is the closure treatment
method? What "standard" will be used to measure successful closure? Do spent
heaps present risks after closure, including ARD potential?
• Will the heap be operated on a seasonal basis? Are temporary closure procedures
proposed? Will the heap be monitored on a regular basis during the inactive
season?
• Will concurrent reclamation be conducted, if appropriate?
• How will reagents be transported/stored? What measures will be taken to prevent
spills? Is there a spill prevention and control plan being developed?
• What measures will be used to limit human and wildlife access to the leaching
operation?
In Situ Mining
• What are the proposed lixiviants? Is there demonstration as to the integrity of the
target aquifer? Are injection and recovery rates sufficient to maintain a cone of
depression within the target aquifer? Are monitoring plans developed to detect
constituents of the lixiviant or an appropriate byproduct? What are the
contingency plans in the event of an excursion? What methods are proposed for
aquifer restoration?
• Have waste streams been identified? What are the expected compositions of
waste materials? How are the end products of each waste stream managed?
Have radionuclide levels been determined, (where appropriate)?
• Are solution ditches and ponds lined? Is there leak detection? Is there a plan to
address spills and leaks?
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Milling Operations
• What types of beneficiation will be used at the mill? What are the waste streams
associated with these operations? What are the constituents of each waste stream?
What type of sampling was conducted to provide the description and was it
representative? Were the waste streams tested using the Toxicity Characteristic
Leaching Procedure (TCLP) or other test method? What were the results?
• How will air emissions be minimized? What technologies will be implemented
for fugitive dust emission control? What performance standards were described
for these technologies? How will air pollution control dust be managed? If air
pollution control dust will be reused, in what process will it be reused?
• How will waste streams be managed? Will on-site ponds be used? Will water
be recycled back to the process?
• Is closure and reclamation of the mill and surrounding area described in detail?
Will the mill be disassembled after the operation is closed? Is the closure and
reclamation proposed for the site described in detail?
• How will reagents be transported/stored? Is there secondary containment? Is
there a plan to prevent/address spills or leaks of reagents, products, and wastes?
Smelting/Refining Operations
• What are the waste streams associated with the smelter or refining operation?
What are the constituents of each waste stream? What type of sampling was
conducted? Was it representative? Were the waste streams tested using the
TCLP or other test method? What were the results?
• How will waste water streams be treated and/or managed? Will on-site ponds be
used? If so, will they be lined? Will the water be recycled back to the process?
• How will slag from the smelting furnace be managed? Will any be recycled back
to the concentrator?
• How will emissions be minimized? What technologies will be implemented for
fugitive dust and gas emission control? What performance standards were
described for each of these technologies? How will air pollution control dust be
managed? If air pollution control dust will be reused, in what process will it be
reused? How and where will air pollution control sludge be managed?
• Where and how are wastes such as bleed electrolytes, acid rinsing, tank bottoms,
vessel cleanouts, used oil, etc. being disposed of? Is the facility permitted?
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• For metallurgical sulfuric acid plants, how will acid blowdown be handled? What
are the characteristics of the acid plant blowdown (constituent concentrations,
etc.)?
Phosphoric Acid Production/Phosphogypstacks
• What is the specific manufacturing process used at the site? What is the water
balance for the facility? What are the current and planned dimensions for the
phosphogypstack and cooling ponds?
• What is the pH and chemical composition (phosphorous, sulfur, fluoride,
radionuclides, metals, etc.) of the phosphogypsum and process
wastewaters/cooling pond waters? If a leaching test was performed on the
phosphogypsum, how was it performed? Because leachate is expected to have an
extremely low pH (< 1), a standard Toxicity Characteristic Leaching Procedure
(TCLP) will likely underestimate leaching potential.
• What other wastes/wastewaters does the operator dispose of in the stacks and/or
cooling ponds?
• What is the capacity of the drainage system? Does it take local climatic factors
into consideration? Is overflow anticipated? If yes, how will it be managed?
• Was an analysis conducted to determine the structural stability of the
phosphogypstacks? Has the analysis been certified by a professional engineer
(PE)? If applicable, did the analysis consider snow loading? Does the
documentation include drawings to verify the structural stability?
• What measures will be used to limit public and wildlife access to the
phosphogypstacks?
• Is there a closure plan for the phosphogypstacks? How long will be required for
the stack to fully drain? Will environmental monitoring continue after closure as
long as the potential for impacts remain?
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5.4 APPENDIX 4: The Berlin Accords
As the Berlin Round Table drew to a close, a series, of discussions were held to obtain
a consensus of the views amongst participants at the meeting. This appendix comprises the full
document submitted.
Worldwide long-term economic development can best be achieved through the pursuit of
sustainable development policies comprising a balance of economic, socio-cultural and
environmental protection measures. While taking into account global environmental concerns,
each country should apply this concept to meet the needs of its environment and economic
circumstances.
Sustainable mining activities require good environmental stewardship in all activities, from
exploration and processing to decommissioning and reclamation. It acknowledges the importance
of integrating environmental and economic considerations in the decision-making process and
the fact that mineral deposits are unique in their occurrence. It recognizes the importance of
mining to the social, economic, and material needs of society, in particular for developing
countries, and the minerals, notably metals, offer great potential for the use of future generations
through increased recycling programmes.
Sustainable mining under appropriate environmental guidelines is based on interaction between
industry, governments, non-governmental organizations and the public, directed towards
optimizing economic development while minimizing environmental degradation. The need for
such guidelines is recognized by industry, governments, and international agencies. It is also
recognized that the political will of governments, together with the commitment of industry
management and that of the community, are the essential conditions needed to enforce
environmental legislation and, more importantly, to ensure compliance with all applicable laws
for the protection of the environment, employees, and the public.
5.4.1 Addressed to the Mineral Sector
Governments, mining companies, and the minerals industries should as a minimum:
1. Recognize environmental management as a high priority, notably during the licensing
process and through the development and implementation of environmental management
systems. These should include early and comprehensive environmental impact
assessments, pollution control and other preventative and mitigative measures, monitoring
and auditing activities and emergency response procedures.
2. Establish environmental accountability in industry and government at the highest
management and policy-making levels.
3. Encourage employees at all levels to recognize their responsibility for environmental
management and ensure that adequate resources, staff, and requisite training are available
to implement environmental plans.
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4. Ensure the participation and dialogue with the affected community and other interested
parties on the environmental aspects of all phases of mining activities.
5. Adopt best practices to minimize environmental degradation, notably in the absence of
specific environmental regulations.
6. Adopt environmentally sound technologies in all phases of mining activities and increase
the emphasis on the transfer of appropriate technologies which mitigate environmental
impacts, including those from small-scale mining operations.
7. Seek to provide additional funds and innovative financial arrangements to improve
environmental performance of existing mining operations.
8. Adopt risk analysis and risk management in the development of regulation and in the
design, operation, and decommissioning of mining activities, including the handling and
disposal of hazardous mining and other wastes.
9. Reinforce the infrastructure, information systems service, training, and skills in
environmental management in relation to mining activities.
10. Avoid the use of such environmental regulations that act as unnecessary barriers to trade
and investment.
11. Recognize the linkages between ecology, socio-cultural conditions and human health and
safety, both within the workplace and the natural environment.
12. Evaluate and adopt, wherever appropriate, economic and administrative instruments such
as tax incentive policies to encourage the reduction of pollutant emissions and the
introduction of innovative technology.
13. Explore the feasibility of reciprocal agreements to reduce transboundary pollution.
14. Encourage long-term mining investment by having clear environmental standards with
stable and predictable environmental criteria and procedures.
5.4.2 Addressed to Development Assistance Agencies
Multilateral and bilateral assistance agencies have an essential role to play in furthering
environmental management, particularly in developing nations, and in assisting these nations in
programmes to protect their environment, both nationally and as part of the global environmental
system. Accordingly, they should:
1. Accord high priority to the mitigation of environmental degradation associated with
mining in developing countries to achieve high environmental performance.
2. Initiate, as an integral part of any exploration and mining project, environmental
institution building programmes. Special support should be giving to countries actively
working to improve their environmental capabilities.
3. Require that all mining projects supported shall contain a training component that will
include specific training on environmental awareness and its application to the mining.
4. Support increased research regarding the development of new processes, with fewer
environmental impacts, including recycling.
5. Support the development of activities that would mitigate adverse effects on the socio-
cultural fabric and the ecosystem. To achieve this objective, international agencies
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should give priority to education and training which increase awareness of these issues
and allow the affected community to participate in decision-making.
6. In supporting mining projects, agencies should also take into account the following:
• rehabilitation of displaced population;
• environmental history of the country;
• large-scale impact on socio-economic patterns;
• the overall economic balance of the project vis-a-vis its total environmental
impact;
• the impact on other natural resources and ecologically sensitive areas (e.g.
protected forest lands, mangroves, wildlife parks, and neighboring waterbodies.)
7. Promote conferences and policy research on environmental management practices and
technologies, and ensure the dissemination of this information.
8. Support and promote regional co-operative programmes to achieve sustainable
development of mineral resources.
9. Adopt environmentally safe methods of mining and processing for existing projects, fl
Increase and co-ordinate their assistance to developing nations in the field of
environmental policies management.
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5.5 APPENDIX 5: Annotated Bibliography
5.5.1 Accessing Information on Mining
A number of organizations have compiled information in recent years on the
environmental impacts of mining. These sources can be contacted by phone, or in come cases
via the internet, for more detailed information on specific topics. Major sources of information
include:
The U.S. Environmental Protection Agency, which provides information on mining
through the National Technical Information System (NTIS) or through the internet (see
the box below). The NTIS can be contacted by calling (703) 487-4600 and requesting
a document by its NTIS number (e.g., PB88-I62631). Some of the documents available
through the NTIS are identified in section 5.5.4.
The U.S. Bureau of Mines, a leading research agency on advanced mining methods and
environmental technology for mine remediation, can be contacted in Washington D. C.
at (202) 501-9770.
The United Nations Environment Program (UNEP) has conducted a number of
conferences and prepared various documents on the environmental impacts of mining.
They can be contacted at: The United Nations Environment Program (UNEP), Industry
and Environment Program Activity Center, 39-43, Quai Andre Citroen, 75739 Peris
Cedex 15 - France. Telephone: 33 (1) 40 58 88 50.
/>
Additional information on mining and the environment can be found through:
The American Mining Congress, 1920 N St., Suite 300, Washington D.C. 20036
Tel:(202)-861-2800
California Mining Association, 1 Capitol Mall, Suite 220, Sacramento, CA 95814
Tel (916) 447-1977, Fax: (916) 447-0348
Colorado Mining Association, 1600 Broadway, Suite 1340, Denver, CO 80202
Tel: (303) 894-0536, Fax: (303) 894-8416
Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401
Tel: (303) 273-3000, Fax: (303) 273-3278
The International Council on Metals and the Environment, 360 Albert St., Ottawa,
Ontario, Canada, K1R7X7
Tel: (613)-235-4263
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Mine Environment-Neutral Drainage Program, 555 Booth Street, Ottowa, Ontario,
K1AOG1
Tel: (613) 995-4681
Northwest Miner's Association, 10 North Post Street, Suite 414
Spokane, WA 99201
Tel: (509) 624-1158, Fax: (509) 623-1241
In addition, most international embassies will have access to their country's mining codes.
EPA Mining Documents Available Through the Internet
As part of an interagency "streamlining" initiative, EPA is making many mining
documents available electronically. They can be accessed in electronic format on the
Internet System through:
EPA Public Access Gopher Server: Go to gopher.epa.gov; From the main menu, choose
"EPA Offices and Regions"; Next choose "Office of Solid Waste and Emergency Response
(OSWER)"; Finally choose"Office of Solid Waste/Other Wastes/Bevill Amendment-Mining
Waste."
Through FTP: Go to: ftp.epa.gov; Login: anonymous; Password: Your Internet
Address; Files are located in /pub/gopher. All OSW files are in directories beginning with
OSW.
Through MOSAIC: Go to: http:// www.epa.gov; Choose the EPA Public Access
Gopher; From the main (Gopher) menu choose "EPA Office and Regions"; Next choose
"Office of Solid Waste and Emergency Response (OSWER)"; Finally, choose "Office of
Solid Waste/Other Wastes/Bevill Amendment-Mining Waste."
Through Dial-up access: Dial 919-558-0334; Choose EPA Public Access Gopher; From
the main (Gopher) menu choose "EPA Offices and Regions"; Next choose "Office of Solid
Waste and Emergency Response (OSWER)"; Then choose "Office of Solid Waste/Other
Wastes/Bevill Amendment-Mining Waste."
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There are a number of good, practical sources that we have used extensively for the preparation
of this support package and that can provide policy-makers with additional information as
needed. These are discussed in more detail below.
5.5.2 The Mining Process
The following sources cover general and specific techniques for the extraction and
processing of minerals. In addition, the reference from the U.S. EPA Office of Solid Waste on
copper mining covers pollution prevention techniques and environmental controls. It includes
a number of detailed case studies on environmental problems at copper mines in the United
States.
U.S. Environmental Protection Agency, Technical Resource Document: Copper, Office of
Solid Waste, EPA, 1994.
This report describes all of the major components of the copper mining process including
types of mines, leaching operations, and waste products.
Contact: U.S. Environmental Protection Agency, Office of Solid Waste, 401 M Street
S.W., Washington D.C. 20460
U.S. Environmental Protection Agency, Extraction and Beneficiation of Ores and Minerals:
Volume 4 Copper, Office of Solid Waste, EPA.
This report provides an informative, non-technical description of copper mining methods
and their environmental effects. It also contains a description of current U.S. regulations
and the organization of mining regulatory administration in the United States. The
document also contains several site case studies detailing environmental inspections at
U.S. mining operations.
Robert W. Bartlett Solutipn Mining: Leaching and Fluid Recovery of Materials,
Philadelphia, Pennsylvania: Gordon and Breach Science Publishers.
This book describes various leaching methods as well as procedures that can be taken
to limit the environmental damage caused by the leaching process. It is written at a
fairly advanced level and requires an understanding ofchemistry for full comprehension
of the details.
Contact: Gordon and Breach Scientific Publishers, P. O Box 786 Copper Station, New
York , New York, 10276
Tel: (718) 273-4700
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A.B. Cummins and I.A. Givens, SME Mining Engineering Handbook, Society of Mining
Engineers of the American Institute of Mining, New York, NY: Metallurgy, and
Petroleum Engineers, Inc., 1973.
Contact: Society of Mining Engineers of the American Institute of Mining, Metallurgy,
and Petroleum Engineers. P.O. Box 625002 Littleton,Co. 801-62-5002.
Tel: (303)-973-9550
A standard text in the industry, this manual presents detailed information on mine
planning and operations.
5.5.3 Pollution Prevention and Environmental Control Technologies
These references touch on most pollution prevention and environment controls applicable
to many types of mining. More detailed references to specific environmental problems
can be found in the sections that follow.
M. Sengupta, Environmental Impacts of Mining: Monitoring, Restoration, and Control,
Boca Raton, Florida: Lewis Publishers, 1993.
This book provides a superb overview of the environmental impact of mining. It presents
specific information on control and prevention options for a number of environmental
problems, including acid mine drainage, hydrologic impact, acid rock drainage, erosion,
and sediment control.
Contact: CRC Press, Inc., 2000 Corporate Blvd., N.W., Boca Raton, Florida 33431.
Tel: (407) 994-0555
United Nations Environment Program, Environmental Aspects of Selected 'Non-Ferrous
Metals Ore Mining, A Technical Guide, Paris, France: UNEP, 1991.
This report provides information on the mining process, major environmental problems,
and some control and prevention options for environmental problems. The report is
written for the non-technical reader and contains numerous notes detailing other sources
of information. The section, Procedures for Environmental Control, is particularly good
for establishing an overall environmental strategy for mining.
Contact: United Nations Environment Programme, Industry and Environment
Programme Activity Centre, 39-43 Quai Andre Citroen, 75739 Paris Cedex 15-France.
Tel: 33 (1) 40 58 88 50. Fax 33 (1) 40 58 8874
U.S. Department of the Interior, Bureau of Mines, Selected Publications and Papers of the
Bureau of Mines, 1993-1994: Environmental Technology, August, 1994.
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This report contains abstracts for Bureau of Mines publications regarding environmental
technology and mines.
U.S. Environmental Protection Agency, Extraction and Beneficiation of Ores and Minerals:
Volume 4 Copper, Office of Solid Waste, EPA.
See description under 'THE MINING PROCESS'
U.S. Environmental Protection Agency, Office of Solid Waste/Office of Federal Activities,
Background for NEPA Reviewers -- Non Coal Mining Operations, EPA, December,
1994.
This report provides a general description of mining operations at non-coal mining sites,
potential environmental impacts associated with these operations, and possible
prevention/mitigation measures that may be taken. The report is intended for use by EPA
staff in conducting National Environmental Policy Act (NEPA) reviews of mining site
decisions. Appendix 3 contains an excerpt from this document highlighting the general
environmental questions that should be addressed to fully understand the environmental
effects of any proposed mining project.
U.S. Environmental Protection Agency, Office of Solid Waste, Report to Congress on Solid
Wastes from Mineral Processing: Volume II, Methods and Analyses, EPA, July, 1990.
This report reviews the source and volume of mining wastes produced annually, present
disposal and utilization practices, potential risks to. human health and the environment
from these wastes, alternatives to current disposal methods, and cost and other
considerations associated with the alternatives. The report was produced as a result of
EPA's exclusion of mining wastes from regulation under the Resource Conservation and
Recovery Act (RCRA) until more information could be gathered about the issue.
5.5.4 Acid Mine Drainage and Leaching
U.S. Department of Agriculture, Acid Drainage From Mines on the National Forests, Forest
Service, March, 1993.
This article details acid mine drainage in U.S. national forests and research efforts to
control its impact.
Contact: U.S. Forest Service, 14 and Independence Ave, S.W. Minerals and Geology
Staff, Fourth Floor Central Wing, Washington D. C. 20250
Tel: (202)-205-1224
U.S. Department of Interior, Bureau of Mines, 810 7th Street N.W., Dept of
Environmental Technology, Mail Stop 6205, Washington D. C. 20241 Tel:(202) 501-9271
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PEI Associates INC, Copper Dump Leaching and Management Practices that Minimize the
Potential for Environmental Releases, Cincinnati, Ohio: U.S. Department of Commerce,
National Technical Information Service PB88-155114, January, 1988.
This report presents a description of the extent of copper dump leaching in the U.S., the
potential for environmental impact, and management practices that can be used to
minimize environmental releases. This report is highly technical and provides detailed
information on copper leaching systems.
Contact: Hazardous Waste Engineering Research Laboratory, Office of Research and
Development, U.S. Environmental Protection Agency, Cincinnati, Ohio 45246.
Tel: (513)-569-7562
5.5.5 Information on Mining and Mineral Processing from EPA's Office of Solid Waste,
Mining Waste Section
Documents Prepared by EPA Office of Solid Waste
Report to Congress: Wastes from the Extraction and Beneficiation of Metallic Ores,
Phosphate Rock, Asbestos, Overburden from Uranium Mining, and Oil Shale, EPA,
December 31, 1985. NTIS # PB88-162631
Report to Congress: Wastes from Mineral Processing, EPA, July 1990.
NTIS # PB90-258492
Strawman II, Recommendations for a Regulatory Program for Mining Waste and
Materials Under Subtitle D of the Resource Conservation and Recovery Act, EPA, May
21, 1990. NTIS #PB91-178418
Summary of Data Presented in the Background Document for Effluent Limitations
Guidelines and Standards - Ore Mining and Dressing Point Source Category.
NTIS #PB94-113388
Summary of Data Presented in the Background Document for Effluent Limitations
Guidelines and Standards - Mineral Mining and Processing Point Source Category.
NTIS #PB94-113396
Summary and Technical Review of Supporting Literature for the 1985 Report to Congress
on Wastes from the Extraction and Beneficiation of Metallic Ores, Phosphate Rock,
Asbestos, Overburden from Uranium Mining, and Oil Shale. NTIS # PB94-113404
Mining Sites on the National Priorities List - NPL Site Summary Reports (listed in
alphabetical order by the name of the NPL site).
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Volume I - Aluminum Company of America to Cleveland Mill.
NTIS # PB92-124767
Volume II - Commencement Bay Nearshore/Tideflats to Kerr
McGee. NTIS # PB92-124775
Volume III - Kerr-McGee Chemical Corporation to Ormet Corporation.
NTIS # 92-124783
Volume IV - Oronogo-Duenweg Mining Belt to Tar Creek.
NTIS # PB92-124791
Volume V - Teledyne Wah Chang to Wayne Interim Storage Facility.
NTIS # PB92-124809
Entire set of volumes I-V. NTIS # PB92-124759
Technical Resource Documents on Extraction and Beneficiation of Ores and Minerals.
Volume 1 - Lead-Zinc NTIS # PB94-170248
Volume 2 - Gold NTIS # PB94-170305
Volume 3 - Iron NTIS # PB94-195203
Volume 4- Copper NTIS # PB94-200979
Volume 5 - Uranium NTIS # PB94-200987
Volume 6 - Gold Placer NTIS # PB94-201811
Volume 7 - Other Mining Sectors NTIS # PB94-201001
Volume 8 - Brine, Solution and Underground Melting NTIS # PB94-200995
Innovative Methods of Managing Environmental Releases at Mine Sites.
NTIS # PB94-170255
Acid Mine Drainage Prediction in Mining NTIS # PB94-201829
Detoxification of Cyanide in Heap Leach Piles and Tailings NTIS # PB94-201837
Design and Operation of Tailings Dams NTIS # PB94-201845
Treatment of Cyanide Heap Leaches & Tailings NTIS # PB94-201837
Acid Mine Drainage Prediction NTIS # PB94-201829
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Documents prepared under grants from EPA Office of Solid Waste
Inactive and Abandoned Noncoal Mines:
Volume I - A Scoping Study. NTIS # PB92-190115
Volume II - State Reports. NTIS # PB92-190123
Volume III - Appendix: State Reports. NTIS # PB92-190131
Entire set of volumes I-m. NTIS # PB92-190107
Volume I - Summary Report (Projected Regulatory, Programmatic and Fiscal Impacts of
EPA's Strawman lion State Mine Waste Management Programs). NTIS # PB92-190156
Volume II - State Reports of Western Governors' Association Mine Waste Task Force
States (Projected Regulatory, Programmatic and Fiscal Impacts of EPA's Strawman II
on State Mine Waste Management Programs). NTIS # PB92-190164
Volume III - Appendix: State Reports (Interstate Coalition on Mine Waste).
NTIS # PB92-190172
Entire set of volumes I-m. NTIS # PB92-190149
Abstracts for Selected Precious Metal Mines. NTIS # PB92-180090
Directory of Mine Waste Characterization and Drainage Quality Control.
NTIS # PB92-180108
Solid Sample Analysis of Spent Ore, South Dakota. NTIS # PB92-203496
5.5.6 International Sources of Information
Gary McGee, Mining and Environmental Law, Ottawa, Ontario: Energy Mines and
Resources Canada.
Overview of Mineral Resources Branch of Department of Energy, Mines and Resources
Canada; includes 1989-1990 Budget, Mandate, and Environmental Programs.
Contact: Mineral Technology Branch, Department of Energy, Mines and Resources
Canada; 555 Booth Street, Ottawa, Ontario K1AOG1 Tel: (613)-995-4119
Bolivian Embassy in Washington D.C., Investment Law, Hydrocarbons Law, and Bolivian
Mining Code, Congress of Bolivia: April 11,1991.
Bolivian mining regulation.
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Contact: Consejo National Canero- CONALCA
Av. La Barranca y Cuarto Anillo, P.O Box: 3566 Santa Cruz-Bolivia
Phones: 343446/343445/341094
Telex 4345 CONALCA BV
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