Selenium’s impact on the environment
As residents living along the Oldman River anticipate the impacts of open-pit coal mining in our headwaters, we should know more about the potential changes in water quality and their effects on river health and, therefore, our health.
Open-pit coal mining involves the removal of rock that sits above the coal seams that the mining company targets for extraction. This rock, or overburden, is typically dumped into the river valleys near the mine where it is exposed to weathering. It is the weathering process that releases pollutants like cadmium, nitrate, sulphate, iron, uranium and selenium into the environment over time — in the form of particulates in the air but, more significantly, into river systems.
Like some other elements, selenium is biphasic which means that it is necessary for life in small concentrations but becomes toxic to aquatic species in concentrations as low as 1.5 mg/l. Selenium ions are soluble in water, so they don’t settle in containment ponds. When released to the environment, selenium (as selenite and selenides) bioaccumulates in the aquatic system. That is, the selenium increases in concentration as it passes from plankton to aquatic invertebrates to fish that live higher in the food web. As such, fish are an important indicator species for water contamination of this type. Species that consume fish along the food chain, like birds and even humans, are also at risk of the health impacts resulting from higher selenium accumulating in their bodies.
You may have heard about the long-term environmental damage and health impacts in Appalachia or in the coalmining regions of Australia. Closer to home, however, look across the Continental Divide, to the Elk Valley, where mountaintop coal mining has been conducted for many years. Industry water-quality reports have indicated a steady rise of selenium and other pollutants in rivers downstream of these coal mining operations. It is no surprise that the Regional Aquatic Effects Monitoring Program (RAEMP) has measured increased levels of selenium in aquatic species that pose greater risks for birth defects and reproductive failures. Trout populations downstream of Tech coal mines have reportedly collapsed in recent years.
In response to this issue, the United States has very recently set selenium standards for transboundary waters, an issue that British Columbia has shown a reluctance to address. This is complicated by the admission of major coal operators that they are unable to control the release of selenium pollution. In other words, once the damage is done, it is virtually impossible to contain, and it persists for decades.
In summary, selenium is one of a number of water pollutants that can be expected from mountaintop removal techniques of coal mining in Alberta’s eastern slopes. We have a current example of rising selenium levels in the Elk and Fording Rivers using the same techniques in similar bedrock as is proposed in our headwaters. And, the technology is not available to control the release of selenium into rivers nor address pollution over the long term after it happens.
The Government of Alberta recently changed the Coal
Policy to allow open-pit coal mining along the eastern slopes, with the exception of Category 1 land. This, in effect, was in direct response to the expressed desires of mining companies to streamline the application process. Though these sorts of projects may create some employment in the short term, there seems to be little consideration of the environmental impacts in the long term. Residents along the Oldman River rely on safe water for an agriculturally based economy, including water demand for irrigation and livestock operations, not to mention human use. There is mounting opposition to the unilateral decision to change the Coal Policy that allows these sorts of coal mining operations to operate in our region — your MLA may want to hear your opinion.
SAGE is a leading voice for a healthy and environmentally sustainable community. For more information on this topic, please visit