Module 8

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Impacts of the project

A key part of the review processes is to identify the potential effects of the mining project and the plans to minimize these effects. In many cases these issues will already be laid out in the feasibility study. However the review process may require studying alternative plans to ensure that the highest environmental standards that can reasonably be employed are employed.

Reclamation bond

A reclamation bond is an amount of money that a company must set aside in order to have the funds to close the mine at the end of its life. The bond will be held in trust by the government or a legal firm. A bond is put in place to ensure that funds are available to properly close the mine in the event that a company goes bankrupt. The amount of a reclamation bond is established based on the closure and reclamation plan presented by the company in consultation with the government. For large mines the total amount of the bond can be tens of millions of dollars or more.

Sustainability

"Development that meets the needs of the present without compromising the ability of future generations to meet their own needs"Brundtland, 1987 The definition of sustainable development that is most commonly used today was presented in the 1987 Brundtland Commission Report titled "Our Common Future." This report stressed the need for the world to progress toward economic development that could be sustained without permanently harming the environment and our ability to live off the planet. The report described three fundamental components or pillars of sustainability: 1. environmental protection 2. economic growth 3. social equity Since the release of the Brundtland report, most of the world's major industries, many of its governments, and the UN have adopted a policy of sustainable development. The mining industry is no exception. Today major mining companies employ the principles of sustainable development in their environmental policies. This has been a very positive move for the industry as it has allowed it to view the impacts of its operations in a more comprehensive manner. The process has not been easy; conflict is still present and consensus is not always possible. But a sustainable approach to mining builds respect among stakeholders and ensures that mining benefits everyone: from the local community to the international investors.

Economics of sustainability

"Implementing the principles of sustainable development can deliver bottom line advantages - such as reduced operating costs and better efficiency - and top line advantages - such as competitive advantage and access to new opportunities."(Newmont Mining Corporation, 2003) Traditionally a high level of environmental performance was often equated with a high cost and the higher the cost the lower the return on investment for shareholders. The cost of operation is always an important factor, and since most mining companies are public companies, they must ensure a good return for their shareholders. Today the economics of mining are integrated with the social and environmental aspects of mining. Most major mining companies see that a solid record of social and environmental performance equates to economic opportunity. A company that has a good record and that works openly with local and international communities will be afforded opportunities that other companies are not.

Social license to operate

"Social License is the formal and informal approval a company needs from stakeholders to conduct its business. It requires a company to develop ongoing, positive relationships with its stakeholders in order to obtain support from people likely to be affected by the company's activities, to operate in their community. A company's performance in the areas of safety, social and environmental management is critical to gain and retain this 'social license', and in doing so, the company is better positioned to gain access to new resources, receive regulatory approval to operate, attract higher-quality employees and enjoy support from a wider range of stakeholders." (Newmont Mining Corporation, 2003). An outcome of sustainability is the concept of a social license to operate. The mining industry understands that it must have the acceptance of "communities" in order to operate. By communities we mean not only local communities, aboriginal groups, and governments, but the international community (e.g., environmental groups, the financial community, customers, shareholders, and international governments). Inherent in this concept is that the local communities will benefit from the mining project. Mining companies must communicate openly with all interested parties and stakeholders and they must have a solid sustainability record in order to have the social license to operate. A company with a bad record that pushes mining operations forward without listening to communities will not be accepted and will find itself unable to operate or have great difficulty in operating in many parts of the world. Today; sustainability pays.

What does a "social license to operate" mean?

Acceptance by local and national communities

Acid rock drainage

Acid rock drainage (ARD) is one of the most important environmental issues facing the industry. ARD is the development of acidic waters as a result of reaction between water and rocks containing high levels of sulphide minerals (mainly pyrite). Many metal mines have high levels of sulphide minerals and thus water passing through the mine or over waste and tailing piles may become acidic. If this water enters the natural environment it can significantly damage and pollute waterways. A critical issue with ARD is that once it starts, it can be very hard to get under control. Many abandoned and old mines sites are sources of ARD as water flows through old workings and waste piles. In some cases, water flowing out of old mines may need to be treated and neutralized for decades.

Acid Rock Drainage and Metal Leaching

Acid rock drainage (ARD) is the natural oxidation of iron-sulphide minerals (pyrite and pyrrhotite) when these minerals are exposed to air and water in the presence of bacteria (the bacteria acts as a catalyst and increases the rates of oxidation). The result of this oxidation is an increase in the acidity of the water. An increase in water acidity then has the effect of dissolving metal-bearing minerals that it comes into contact with and increasing the metal content of ARD water. ARD is one of the most significant environmental issues in the mining industry. A general formula (unbalanced) for ARD is as follows: FeS2 + O2 + H2O + bacteria = Fe(OH)3 + SO42- + H+ FeS2 = Pyrite O2 = oxygen H2O = water Fe(OH)3 = limonite (essential rust) SO42- = sulphate H+ = hydrogen ion (hydrogen ions produce acidic water) A significant number of mineral deposits contain pyrite and other iron-sulphides as one of the mineral constituents. Although pyrite is not economic, it is mined along with valuable minerals that contain elements such as copper, zinc and gold. Once pyrite is removed from the ground it is exposed to air and will start to oxidize. Since pyrite is considered waste material, it is separated from the valuable minerals and placed in waste piles or disposed of in tailings. This means that both the waste piles and tailings are potential sources of ARD. Also, underground or open pit workings exposure pyrite to air that was previously isolated below ground. Any water running over these exposed workings may then become acidified. Acidic waters can be neutralized naturally when the water comes into contact with acid-consuming material. The primary material that reduces this acidity is the mineral calcite (CaCO3). The first choice in dealing with ARD at a mining operation is avoidance: ensure that ARD does not develop. Once ARD develops it can be hard to control and control measures, such as water treatment, can go on indefinitely. Control strategies for ARD fall under three groups: primary, secondary and tertiary.

Closure and Reclamation

All mines have a finite life. Once the ore is gone, the mine closes and the mine site is reclaimed back to its natural state, or to a state that is as close as possible to the pre-mining environment. A comprehensive baseline study and a mine plan that has incorporated closure from the beginning makes it much easier to return the land to its pre-mining state. 1. Closure encompasses all aspects of shutting down a mine and returning the area to a pre-mining state. 2. A key to the closure of the mine is to establish an end-land-use plan for the site. In other words, what will the mine site look like and how will the lands be used after the mine is closed and fully reclaimed? 3. Reclamation is generally considered the part of closure that involves revegetating land to a useable and/or natural state.

Baseline studies

Before a company can apply for a permit to develop a mine, extensive studies about the state of the physical environment must be undertaken. These studies establish the "baseline" before mining commences. This information is used in the planning and development of the mine; so that environmental impacts can be minimized. It is also used to monitor the effects of the mine during operation. Upon closure, the land should be returned to the "baseline" that existed before mining. Baseline studies usually take several years to complete and some studies such as water monitoring often start in the exploration stage. The biggest part of a baseline study involves studying the physical environment; however, the cultural, social and economic environments must also be considered. Data for the baseline study is produced by the company in the field, and from existing sources such as federal and provincial government data and reports.

Environmental assessment

Before any major mining operation can be put into development it must undergo an environmental review or assessment as legislated by local or national governments. The assessment process is to ensure the operation does not have an unacceptable effect on the environment. Each jurisdiction has different regulations governing environmental review and some are more stringent than others. In British Columbia, most major projects of any nature (including mining) must undergo a review. A typical environmental assessment contains the following elements: 1. An opportunity for all interested parties to identify issues and provide input. 2. Detailed technical studies of all relevant environmental, social, economic, heritage and health effects of the project. 3. Identification of ways to prevent or minimize undesirable effects and enhance desirable effects of the project.

Abandoned and old mine sites

Canada has well over 10,000 abandoned and old mines sites scattered throughout the country. There are more than 6,000 sites alone in Ontario. These sites pose a number of environmental issues ranging from public safety hazards and visual scars, to metal contamination and acid mine drainage. The majority of these mines sites are benign and have been reclaimed naturally, but several continue to be major environmental problems (e.g., metal contamination and acid rock drainage from the Britannia Mine near Vancouver, BC and arsenic contamination from the Giant Mine near Yellowknife, NT.

Consultations

Consultations are a vital part of the review processes. All interested parties are provided with detailed studies about the project and are given the opportunity to provide input. Interested parties include local communities, groups and governments, First Nations and national and international groups. Mining companies that adhere to the principles of sustainability will have undertaken consultations continuously since the exploration stage and should already be aware of, and have addressed major concerns before they officially start the review process.

Environmental Practice through the Life Cycle of Mining (1)

Environmental practice is part of the full life cycle of mining. It is integrated into all aspects of mining from mineral exploration through to closure and in some cases long after the mine has closed.

Closure

Examples of the kind of activities that are undertaken to close a mine are: Removal of buildings and building foundations (unless the buildings can be used for another purpose, such as a business park). This process is made much easier if the buildings were designed to be taken down and removed. Collection and treatment of any soil or ground materials that have been contaminated with substances such as oil. Sealing off underground openings and fencing dangerous surface areas. Monitoring ground and surface water in and around the mine site. This will likely continue for many years to ensure that contaminants are not emanating from the closed mine site. Monitoring and testing of any waste rock piles or tailings piles that have ARD potential. This will also continue for many years to ensure ARD does not develop.

Exploration

For the most part, mineral exploration has a minimal effect on the environment. Most work that is conducted is low impact and may only involve cutting a few trees for grid lines or helicopter pads. At the more advanced stages of exploration, road building, trenching and drilling can have a moderate effect on the environment, with road building often the most significant. In many jurisdictions, permits are required before exploration can be undertaken. These permits specify what type of work will be undertaken, including the number of kilometres of road building, the amount of trenching and the metres of drilling. Often, roads and trenches will have to be removed and reclaimed once work is complete. Depending on the location of the exploration program, local communities and land owners may need to be consulted and their concerns addressed. Although exploration has a relatively low environmental, social and economic impact, high standards of environmental performance are still required and significant environmental impacts must be minimized and reclaimed after work is complete.

Who is credited with the commonly used definition of sustainability?

Gro Harlem Brundtland

Biosolids are used in the reclamation process to ______________________.

Improve the fertility of soil

What is NOT included in Placer Dome's sustainability policy

Increase production rates each year

Adhering to the principles of sustainability can lead to economic benefits for mining companies by:

Increasing development opportunities

History of Mining and the Environment

Mining in the early part of the 20th century was nothing like it is today. In the early 1900s, the environment was given little concern. Waste material from a mine was simply dumped in a convenient location and, when mining was complete, the workers packed up and left without any effort to close the mine in a safe and environmentally sound manner. The industry had little or no knowledge of acid rock drainage, or the long term effects of soil, water, and air pollution emanating from mines and facilities. These past environmental practices have left a legacy of problems that continue to plague the industry. One of the most significant problems is public perception. Mining is one of the least appreciated industries in our society. Most people presume it is dirty, unsafe, and environmentally unsound. In fact, surveys completed in the United States, suggest that the public's perception of mining is at the bottom of the list of industries, falling below tobacco. Although modern mining is highly regulated, productive, and environmentally sound, the history of past practices continue to haunt it.

Dust and airborne particulates

Mining operations can generate elevated levels of dust in the blasting, transportation, crushing and stockpiling of ore and waste rock. A variety of measures are put in place to limit the amount of dust and airborne particulates that occur on the mine site or that leave the mine site. Examples include: 1. Watering roads. 2. Spraying waste rock piles with sealants. This is also used to prevent dust problems when coal is transported by open rails cars. 3. Storing crushed ore in enclosed structures. Revegetating waste piles and tailings piles as soon as possible. 4.Adding filters to remove exhaust fumes from generators and heavy equipment. 5. Adding scrubbers and filters to smoke stacks to remove metals, sulphur dioxide and other contaminants prior to release of gasses to the air.

Water pollution

Modern mining operations are now designed as closed systems where all water entering the mine site, or on the site is collected and reused in the operation. If there is an excess of water on the site, it is treated and cleaned before being released back to the environment. In the past, careful control and treatment of mine water was uncommon. This led to the release of polluted water that could travel long distances in river systems or in ground water. The result was environmental damage over a large area. Some of most common water pollution issues were: 1. Mine dewatering: Ground water flowing into a mining operation requires continual removal while the mine is operating. Once this water enters the mine it may become acidified from reaction with exposed ore (acid rock drainage), or it may be contaminated with chemicals such as residual nitrates from blasting. 2.Effluents from the milling process: A variety of chemicals are used in the milling process (e.g., cyanide). Release of these chemicals with the waste water from the mill was a significant pollution issue. 3. Surface water drainage: Surface water running over the mine site may pick up residual chemicals such as oils and lubricants from equipment. Even surface water that is cloudy with dust and dirt is an environmental contaminant. Water running over and through waste pile

Environmental Practice at the Operating Mine

Modern mining operations have integrated environmental applications into the everyday activities of the mine. Every department works to minimize the effects of the operation on the environment. Most mines have an environment department, but this department works on large issues such as planning for closure or integrating environmental work between other departments at the mine. It is the expectation that every employee continually looks for ways of improving the environmental performance of the mine. Although every operating mine is different, there are general environmental principles under which they work.

What does a positive water balance at a mining operation mean?

More water enters the mines site than is used by the mine

Noise reduction

Noise can be a safety and environmental problem for workers on the mine site and for communities around the mine site. Examples of noise control include: 1. Installing noise reduction filters on heavy equipment, fans, and generators. 2. Building berms around the mine to reduce the amount of noise leaving the site. 3.Optimizing the design of blasts to limit the noise, and timing the blast so it has the least disturbance to surrounding communities.

Introduction

Our environment--the air, water, land, plants and animals around us--is vital to our existence and well being. For hundreds of years, human society developed and expanded with little notice of or concern for the environment. Our resources seemed endless and our natural world very large and adaptable. However, today we know that we cannot continue to expand and use our world's resources without due regard for the environment.

What is the aim of primary control measures for ARD?

Prevent ARD from developing

Spraying waste rock piles with sealants is undertaken to _______________.

Prevent dust pollution

Primary Control Measures

Primary control measures are those that prevent ARD from developing. Some of the techniques that are used include: 1. Segregation and disposal - segregate acid-generating material from non-acid generating material and dispose of the acid-generating material underground or underwater if possible. 2. Blending and Neutralizing - blend acid generating material with neutralizing material such limestone (limestone is comprised of the neutralizing mineral calcite). 3. Covers and Seals - prevents oxygen and water from interacting with acid-generating material. Water is the best cover, but dry covers such as soils and concrete may work.

Reclamation

Reclamation of lands used in the mining operation begins as soon as the land is no longer needed in the operation. For example a waste or tailings pile that has reached its maximum capacity will be contoured, covered with overburden and planted with grasses, shrubs and trees while other parts of the mine continue to operate. The aim is that the process of returning the mine site to its natural state will be well underway by the time the mine officially closes. For example, the Highland Valley Copper Mine near Kamloops, BC began operation in 1960 and continues to operate today. Reclamation activities started on the mine site in 1980 and by 2003, one third of all the land disturbed by mining has been reclaimed.

Reclamation 2

Reclamation of the mine site will be based on the end use plan for the area. Some parts of the mine, such as open pits will become lakes, others may become grazing areas for cattle and still others will become forest lands. Steps: recontouring, capping with a growth medium, seeding and fertilizing, monitoring

What are the three main components of a modern mining company's sustainability policy?

Social, economic and environmental

Sustainability

Sustainability is the ability of an industry to meet the needs of the present generation, without compromising the ability of future generations to also meet their needs. This simple definition has wide ranging implications for the mining industry and is key to our future success. Sustainability is also essential to maintain a "social licence to operate." Mining must have the support of the communities and countries in which it operates in order to be successful. Support is garnered by adhering to the principles of sustainability and ensuring high standards of environmental performance.

Technical studies

Technical studies include baseline and feasibility studies. Baseline studies identify the current state of the environment and feasibility studies provide details of the mine layout and its operating and closure plans.

Tertiary Control Measures

Tertiary control measures involves the long-term collection and treatment of ARD waters. This is a very costly process that can go on indefinitely. It should be avoided at all costs.

advantage of starting reclamation

The advantage of starting reclamation while the mine is operating is that any problems in the reclamation process, such as growth or survival issues, can hopefully be corrected prior to closure and final reclamation of the mine site.

Length of assessment process

The length of a typical assessment process ranges from 9 months to several years. Companies that have undertaken community consultation and extensive studies prior to launching the review processes can complete the processes quickly. Unfortunately, however, these processes can get bogged down in politics and take many years to resolve.

Mining and the environment

The mining industry has followed the same trend as society. Early mines had little, if any, regard for the environment, and were often simply abandoned once the ore body was depleted. However, over the past 50 to 60 years, and in particular over the past 20 to 30 years, the mining industry has come to understand its impact on the environment. Today, we design, develop, operate and close mines in an environmentally sound manner, and great effort is put into continually improving our environmental standard and record. The environment is a diverse and complex topic that extends well beyond the traditional concept of the environment, including the physical environment of air, water, plants, and animals. Today the mining environment includes the social environment, the economic environment, and the health and safety of anyone involved or affected by the industry. It also includes sustainability.

Air pollution

The production of metals such as copper, nickel, zinc, and lead have traditionally required smelting. Conventional smelting techniques involve heating the sulphide minerals containing these metals to extreme temperatures and driving off the sulphur in the form of sulphur dioxide gas. In Canada, prior to around 1970, the sulphur dioxide gas together with vaporized metals and other pollutants was released to the environment virtually unchecked. These gasses settled to the ground producing acidified and polluted lakes and soil, often more than 100 kilometres from the smelter smoke stack. For example, in Sudbury, Ontario more than a century of metal mining and smelting denuded large areas around the city of its vegetation and acidified an estimated 7,000 lakes over an area of 17,000 square kilometres. Pollution control measure implemented in the 1970s and 1990s have reduced sulphur dioxide and gas emissions by more than 90% and much of the area around Sudbury is returning to its natural state.

Sustainability and Environmental Policies

The sustainability and environmental policies of most major mining companies are similar. They are all built upon the premise that the metals and minerals are needed by society for things such as energy generation and transmission, mobility and transportation, information and communication, food supply, health delivery, and countless other services. In short, mining is essential to our everyday life. Placer Dome Inc., a Canadian-based international gold mining company, is at the forefront of developing a sustainability policy. Its policy is a good example of what most major mining companies have in place. Placer Dome's Policy states: "Our commitment to sustainability ensures we explore and design, construct, operate and close mines in a way that respects and responds to the social, environmental and economic needs of present generations and anticipates those of future generations." Placer Dome's policy ensures that it will: 1 Regularly assess environmental conditions through all stages from exploration through mine closure, identifying all issues of environmental concern and establishing objectives and strategies for their management. 2 Provide for the effective involvement of communities in decisions that affect them, to treat them as equals, respect their cultures, customs and values, and take into account their needs, concerns and aspirations in making our decisions. 3 Establish credible monitoring and verification programs to measure impacts and ensure compliance with legal requirements and with our sustainability policy, and communicate the results in an effective manner. 4 Provide training and resources to develop employees and build competencies related to environmental and social responsibilities. 5 Conduct or support research programs to expand knowledge of the impact of mining activities on the environment and the community. 6 Work actively with government, industry and stakeholders to improve public policy, laws, and regulations in support of sustainability. Implementing a sustainability policy such as Placer Dome's is not easy, and each exploration program or mine site must adapt to suite its unique situation. There is also no guarantee that consensus will be reached; conflict still occurs. However open communication, education, and respect will minimize conflicts and ensure that the mine provides the most benefit that it can to society.

What is the Mining Environment?

The traditional concept of the environment is the physical environment that relates to air, water, land, plants and animals. However, to a modern mine, the environment also includes social, economic, and health and safety issues. A sound mining operation with a high level of environmental performance is one that: 1. preserves and protects the natural environment 2. respects and supports the communities and social structure where it operates 3. generates wealth for the company, its employees and the community 4. ensures the health and safety of its employees and the surrounding community Today most major mining companies and their operations integrate their environmental activities into a comprehensive sustainability policy that has three main components: social, economic and environmental.

seeding and fertilizing

This usually take place over many years. Initially fast growing grasses are planted in order to stabilize the soil, this is followed by shrubs and then trees depending on the end use plan. In the case of pits or areas that will become lakes, aquatic vegetation and fish are introduced.

Why is a reclamation bond required before a mine goes into development?

To ensure there are funds to properly close the mine

Capping with a growth medium

Waste rock piles and other areas of the mine site will need to be covered with a soil material that is suitable for the growth of plants. In many cases soil and overburden have been stockpiled on the mine site in anticipation of reclamation.

When does reclamation begin?

While the mine is operating

What is the biggest effect of mineral exploration on the land?

access roads

Acid rock drainage develops when iron-sulphide minerals come in contact with ________________.

air and water

Monitoring

all reclaimed areas are monitored and assessed for vegetation survival and growth rates. Plants in areas that are to be used for grazing will be tested to ensure they contain acceptable levels of metals and other possible contaminates.

Which of the following is NOT a step in the reclamation processes?

illing

Which of the following is NOT a component of a baseline study?

mine planning studies

What is the traditional concept of the mining environment?

physical environment

Acid rock drainage develops in rocks that have a high content of _____________?

pyrite

Secondary Control Measures

secondary control measures are those that prevent or reduce the migration of ARD waters. Techniques include: 1. Diversion - construction of drainage ditches and berms around waste and tailings piles. 2. Groundwater interception - selecting sites that avoid groundwater discharge zones and placing impermeable layers at the base of waste piles. 3. Covers and Seals - prevent water from flowing into or out of a acid generating pile of material or to underground workings.

Baseline studies usually take _________________ to complete. Question options:

several years

What part of the mining operation was historically the biggest contributor to air pollution?

smelting

Recontouring

the ground is resloped and contoured to a final profile that will be stable, provide for proper drainage, facilitate the grow of vegetation, and provide varied habitat for wildlife (or habitat for grazing depending on the end use plan). This may include creating wetlands, streams, ponds or lakes.

Why are hydrology and water quality surveys undertaken as part of a baseline study?

to estalish water quality

Which of the following is NOT a significant problem with abandon mine sites?

unpaid taxes


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