Water is essential to life on our planet. A prerequisite of sustainable development must be to ensure uncontaminated streams, rivers, lakes and oceans.
As Canadians, we often take the presence of clean water for granted, forgetting its importance and assuming that it is always available. Unfortunately, the law and technology to protect this vital resource remains far from perfect. Increasingly, human activities threaten the water sources on which we all depend. Mining is one such activity. In fact, water has been called "mining's most common casualty."
There is growing awareness of the environmental legacy of mining activities that have been undertaken with little concern for the environment. The price we have paid for our everyday use of minerals has sometimes been very high. Mining by its nature consumes, diverts and can seriously pollute water resources. Changes in laws, technologies and attitudes have begun to address some of the most immediate threats posed by mineral development, but there are still many areas of mining practices and regulations that need to be addressed.
For example, according to the 1993 BC State of the Environment Report, mine drainage is "one of the main sources of chemical threats to groundwater quality" in the province. Groundwater supplies the drinking water of more than half the people living outside of Greater Victoria and Greater Vancouver.
For the sake of current and future generations we need to safeguard the purity and quantity of our water against irresponsible mineral development. We need to ensure the best pollution prevention strategies are employed in cases where the risks can be managed. But we also need to recognize that in some places mining should not be allowed to proceed because the identified risks to other resources are too great.
While there have been improvements in mining practices in recent years, significant environmental risks remain. Negative impacts can vary from the sedimentation caused by poorly built roads during exploration through to the sediment, and disturbance of water during mine construction. Water pollution from mine waste rock and tailings may need to be managed for decades, if not centuries, after closure. These impacts depend on a variety of factors, such as the sensitivity of local terrain, the composition of minerals being mined, the type of technology employed, the skill, knowledge and environmental commitment of the company, and finally, our ability to monitor and enforce compliance with environmental regulations.
One of the problems is that mining has become more mechanized and therefore able to handle more rock and ore material than ever before. Consequently, mine waste has multiplied enormously. As mine technologies are developed to make it more profitable to mine low grade ore, even more waste will be generated in the future. This trend requires the mining industry to adopt and consistently apply practices that minimize the environmental impacts of this waste production.
As a recent book published by the Mineral Policy Center put it, "Once a mine is in operation water protection must remain the highest goal of the company, even if it means reduced mineral productivity. Adopting this common-sense ethic is the only way we can ensure that the golden dreams of mining do not turn into the nightmare of poisoned streams."
In the right place - and with conscientious companies, new technologies and good planning - many of the potential impacts are avoidable. In fact, most mine pollution arises from negligence, not necessity.
For more information on mining's impact on water, see our report on Acid Mine Drainage and water issues (from which this module is excerpted).