Environmental Code of Practice for metal mines: chapter 1
The Environmental Code of Practice for Metal Mines (henceforth called the "Code") is designed to support the Metal Mining Effluent Regulations (MMER 2002) under the Fisheries Act and includes other subjects that are not dealt with in the MMER that may have an influence on the environmental impact of mining operations. The Metal Mining Effluent Regulations (MMER) were registered on June 6, 2002, under subsections 34(2), 36(5) and 38(9) of the Fisheries Act.
The MMER applies to all Canadian metal mines (except placer mines) that exceed an effluent flow rate of 50 cubic metres per day and deposit effluent into fisheries waters at any time after the regulations were registered. The MMER prescribes limits for arsenic, copper, cyanide, lead, nickel, zinc, total suspended solids (TSS), radium-226, and pH in mine effluent. The MMER also includes a requirement that effluent be non-acutely lethal to rainbow trout.
Mines subject to the MMER are also required to conduct Environmental Effects Monitoring (EEM) programs in accordance with prescribed criteria. The objective of EEM is to evaluate the effects of mining effluent on the receiving aquatic environment, specifically with regard to effects on fish, fish habitat, and the use of fisheries resources.
The starting point for the development of the Code of Practice is the final report (1996) of the multi-stakeholder Assessment of the Aquatic Effects of Mining in Canada (AQUAMIN). AQUAMIN was initiated in 1993 to evaluate the effectiveness of the Metal Mining Liquid Effluent Regulations (MMLER). This process included consideration of the Environmental Code of Practice for Mines that was published in conjunction with the MMLER in 1977.
The AQUAMIN Final Report advanced the following recommendations specific to the 1977 code of practice:
- that the code of practice be updated;
- that the updated code continue to have a significant focus on the issues related to water management and water pollution prevention;
- that the updated code also address other issues, including stakeholder involvement; and
- that the code be revised by updating existing material and adding new sections to address other aspects of environmental management and monitoring.
The AQUAMIN report also recommended that the content of the updated code should:
- emphasize the principles of pollution prevention;
- be applicable to all phases of mining activity;
- provide references to address the production, prevention, control, treatment and monitoring of acid mine drainage, site management of fuels, reagents, solvents and refuse, power generation, and site close-out; and
- recommend measures to involve communities and Aboriginal groups.
It is important to note that while this code is intended to apply specifically to metal mines, the recommendations in the document may be helpful to all sectors within the mining industry.
1.2 The Metal Mining Sector in Canada
As noted above, the primary focus of this document is metal mines that are extracting minerals that contain metals such as copper, nickel, iron, uranium and gold. In this document, mining also includes the primary processing of the minerals extracted to produce a metal concentrate or other product for sale or further processing.
Metal mines in Canada are commonly classified by primary commodity type, as follows:
- base metals, primarily copper, zinc, lead and nickel;
- precious metals, primarily gold, platinum group metals, and silver;
- iron ore; and
- other metals, including titanium, tantalum, tungsten, niobium and magnesium.
To give an indication of the geographic distribution of metal mining facilities across Canada, the locations of mines are illustrated in Figure 1.1.
Figure 1-1: Distribution of mining facilities subject to the Metal Mining Effluent Regulations in Canada in 2007
This figure illustrates the distribution of mining facilities subject to the Metal Mining Effluent Regulations in Canada in 2007. A map of Canada with population centres and major water bodies is shown containing numerous points to indicate the sites of mines and related facilities across the country. Iron ore facilities are clustered in the east, mainly in Labrador, while uranium sites are in Saskatchewan. Base and precious metal facilities are spread out across the country, with clusters in north central Ontario/Quebec, Manitoba, and British Columbia.
The mine life cycle typically includes the following phases: exploration and feasibility, planning and construction, operations, and closure. Activities associated with the mine life cycle may include:
- line cutting, drilling, trenching and bulk sampling;
- development of mine workings and construction of associated infrastructure;
- extraction of ore;
- management of mine and site drainage;
- ore processing;
- disposal of waste rock, tailings and other wastes; and
- site reclamation activities.
Mining facilities are faced with the challenge of managing large volumes of ore, waste rock, and tailings, the disruption of the surface, and the need to address ongoing reclamation of the operational area.
1.3 Code Objectives and Scope
The overall objective of the Code is to identify and promote recommended best practices in order to facilitate and encourage continual improvement in the environmental performance of mining facilities throughout the mine life cycle, in Canada and elsewhere. It addresses all phases of the mining life cycle from exploration and feasibility studies through planning and construction, operation, and closure, and it covers a broad spectrum of environmental aspects ranging from air, water and waste management to biodiversity.
The Code is intended to be a resource for mine owners and operators and regulatory agencies, as well as the general public, particularly those people in communities potentially affected by mining activities.
The Code first describes the major operational activities that occur through the mine life cycle and the environmental concerns associated with these activities. It then presents recommended best practices to minimize the environmental impacts associated with mining operations. Recommendations are accompanied by background text that provides explanation of the rationale for the recommendations and information on the concerns to be addressed. These recommended best practices may be used by the mining sector, regulatory agencies, and the general public as sources of technical and policy guidance in the development and implementation of site-specific environmental protection practices.
Although the recommendations are intended to be clear and specific to the intended results, they are not intended to discourage the use of alternative technologies and practices that can achieve an equivalent or better level of environmental protection.
A glossary of key terms as well as a list of additional resources that were considered in the development of the Code is provided immediately following Chapter 4. The glossary should be consulted to clarify the precise meaning of terms that are used in this document, and the additional resources may be of value in helping readers determine how best to implement specific recommendations that are presented.
1.4 Code Development
The Code was developed by Environment Canada in consultation with a broad range of stakeholders.
Relevant federal, provincial/territorial, and international environmental standards were considered in the development of the recommendations in the Code. Environmental management practices recommended by various national and international organizations were also incorporated. Information on best management practices was drawn from various reports and literature produced by provinces/territories, Environment Canada, the Mine Environment Neutral Drainage Program (MEND), the Government of Australia, the United Nations and the Mining Association of Canada, as well as from individual mining facilities and technical journals. The document has also been widely reviewed by staff from federal, provincial and territorial governments, the mining industry, and a range of other stakeholders.
1.5 Code Implementation
The Code of Practice will be adopted by Environment Canada and others as a guidance document that recommends environmental protection practices for metal mines.
The Code may be adopted on a voluntary basis by individual mining corporations for activities in Canada and other countries, by the Mining Association of Canada (MAC) and its members, provincial or territorial mining associations or other industry associations. A commitment to this code may be included in environmental performance agreements that are entered into by mining companies or individual facilities with Environment Canada and provincial, territorial and Aboriginal environmental departments. It may also be adopted in whole or in part by regulatory agencies.
Some or all of the recommendations in the Code may be used as a requirement by financial lending institutions and/or insurance companies or underwriters.
The Code may be used for benchmarking best practices to achieve continual improvement in the environmental performance of metal mines in Canada and other countries. Code recommendations may also be used as benchmark criteria for use in audits of the environmental performance of sector facilities or companies.
Recommendations in the Code do not carry regulatory status, and a commitment by companies to implement the recommendations in the Code does not remove obligations for such companies to comply with all applicable municipal, Aboriginal, provincial, territorial and federal legal requirements.
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