What can we learn from this graph?

According to these data, the selenium concentration in the Elk River has increased downstream of mines since recording began in 1985. By comparing different sites, we can start to piece together a clear story. Upstream from mines, at the “Elk River Above Greenhills Mining Operation” location (red), most water impacted by mine waste rock has not entered the river. A this site, concentrations are close to background levels (~0.9 µg/L). Similarly, by monitoring non-mine-impacted streams, ERA found that background concentration of selenium is about 0.4-1.25 µg/L. By contrast, monitoring sites downstream of mine operations (green and purple), are considerably higher, averaging about 10 ug/L and reaching as high as 20 µg/L. As you go further downstream, more creeks and groundwater flow into the Elk River and the concentrations are diluted. By the time water reaches the outflow into the Koocanusa Reservoir (orange), the concentration is about 5-7 ug/L; this is still considerably higher than background concentrations. You might also notice a fluctuation, repeatedly going up and down. This is a seasonal pattern that happens when high snowmelt in May-July dilutes the water and decreases concentrations.

Over the last few years, the rate of selenium increase shows some signs of slowing down. The actual concentrations of selenium are not yet decreasing. Moreover, some streams on mine sites show much higher levels than above; for example, close to the Fording River mine a Compliance Test Point monitored by Teck (Site FR_FRCP1), had concentrations of selenium reached 674 µg/L in 2020 (Teck 2020 FRO LAEMP). Selenium concentrations in the Elk River have not been below the BC Aquatic Life Guideline levels* (which are designed to protect all aquatic life, including the most sensitive species) since 2009, and frequently exceed the BC Source Drinking Water Guidelines at the Sparwood monitoring site.

*Note: Water quality guidelines, such as the ones for aquatic health and drinking water, are not based on levels where adverse impacts on health have been reported. They are used as a signal threshold at which monitoring and mitigation strategies should be implemented to decrease the risk of adverse effects on aquatic life or human health.

Does swimming in the Elk River selenium pose a risk to people’s health?

Mammals, including humans, are far less sensitive to selenium compared to fish or other organisms (such as birds) which feed on aquatic plants and insects. Most of the selenium intake in humans comes from diet and dietary supplements and is not absorbed through the skin. According to the BC Ministry of Environment’s Ambient Water Quality Guidelines for Selenium Technical Report Update (2014, pg. 93, section 7.1.1.1) “Selenium compounds are not easily absorbed through the skin; there is little information concerning systemic effects of dermal exposure to Se compounds in humans”. Because selenium is not easily absorbed through the skin, It is highly unlikely that swimming in the Elk River would cause negative effects from exposure of skin to selenium.

Does Elk River selenium pose a human risk for drinking water?

BC Source Drinking Water guideline levels for selenium are 10 µg/L

Health Canada’s Guidelines for Canadian Drinking Water Quality 50 µg/L

Currently, the Elk River selenium concentrations frequently exceed the BC drinking water guideline—however, serious effects from drinking the water are unlikely. According to the Government of Canada, the adult recommended daily intake of selenium is 45 µg, with the Tolerable Upper Intake Level (highest levels where adults are unlikely to experience adverse effects) being 400 µg (see link). At current average Sparwood concentrations in the Elk River (~10 µg/L) an adult would need to drink 4 liters of river water to reach their recommended intake and 40 liters to exceed the Tolerable Upper Intake Level. So far, selenium levels in the Elk River do not exceed Canadian Drinking Water Quality Guidelines of 50 µg/L. Therefore, consuming small amounts of river water is unlikely to cause problems. Selenium concentrations notwithstanding, drinking untreated water from the river is highly discouraged.

Is Elk Valley tap water safe to drink?

Fernie gets ~70% of its water supply from Fairy Creek, and tributary creeks have considerably lower selenium concentrations (~0.5-1.25 µg/L) as they are not affected by mining. When the water supply from Fairy Creek is not sufficient, a water well in James White Park is used for water. According to the City of Fernie, there are occasional exceedances of tap water above the 10 µg/L guideline, with 12 µg/L being recorded in 2023. Fernie drinking water reports are released here. While these concentrations are unlikely to have consequences, the City of Fernie is currently exploring alternate water sources not impacted by the Elk River.

Sparwood gets its water supply from three wells. When monitoring showed that one of the wells had selenium concentrations above the BC drinking water guideline at certain times of the year, a new well was installed and the well with exceedances was shut down. Concentrations of selenium at all current water supply wells are consistently below the drinking water guideline and monitoring data show that the wells have little connectivity to the Elk River or Michel Creek (see District of Sparwood website for more information).  

Elkford uses water wells for its water supply. ERA has not yet received a response about Elkford drinking water testing.  

In other locations in the RDEK Area A: Elk Valley residents outside of municipal water systems typically get their water from groundwater wells, and selenium levels will vary depending on location. If you get your water from a private water well, testing your water for quality (for all potential contaminants) is recommended. See the Health Canada website on water testing for more information.

Are Elk River fish safe to eat?

Currently there are no selenium-based fish consumption advisories in British Columbia.

Fish populations in the Elk Valley are under strain of multiple human stressors (forestry, mining, urban pollution, agriculture, climate change). Westslope cutthroat trout in most locations in the Elk Valley are catch-and-release only. ERA strongly encourages all anglers to practice responsible catch-and-release to preserve this important population of the species.

Where fish consumption is permitted (for certain species, at certain locations in the watershed), the effect of selenium on dietary safety depends on how much fish you consume. The BC Ministry of Environment Water Quality Guidelines, outlines “screening values” which are thresholds at which health monitoring should be undertaken. These thresholds are designated based on the concentration of selenium in fish tissues, as well as the daily fish consumption amounts. The selenium screening value for people who have a high fish intake (220 g/day, about one fish steak per day) is 7.3 mg/kg (dry fish muscle weight). The screening selenium concentration for people who have a low fish intake (30 g/day, one fish steak every week) is 75 mg/kg. The Regional Aquatic Effects Monitoring Program report  published by Teck in 2020 shows that the concentration of selenium in Westslope cutthroat trout muscle tissue in mine-affected creeks is on average ~8 mg of selenium per kg of dry muscle tissue (i.e., mg/kg) and up to 13 mg/kg in some locations (see Table F.1). Based on these numbers, occasional consumption of Elk Valley fish from mine-affected streams would not exceed the screening values, however daily consumption may exceed screening values. Mountain Whitefish typically have lower concentrations of selenium (see Table F.5) and the body tissue selenium concentration of Westslope cutthroat trout in non-mine-affected streams is considerably lower: 4.36±0.55 mg/kg as reported in Kuchapski and Rasmussen (2015) and an average of 1.29 mg/kg as reported by Henderson and Fischer (2012) (see MOE Water Quality Guidelines). Even high, subsistence level, fish consumption in non-mine-affected creeks is unlikely to trigger screening value thresholds.

At high enough concentrations, selenium can cause body deformation in developing fish. This causes lower survival rates of young fish and this, in turn, can contribute to fish population decline. In the Elk River, the Westslope cutthroat trout is a species of Special Concern under the Species At Risk Act, and is affected by the cumulative effects of multiple stressors (including habitat degradation, fishing, climate change, etc.). The additional stressor of selenium pollution decreases the chances of maintaining a healthy population.

How does high selenium impact fish health?

1. Selenium “bioaccumulates” in animal tissues:
   • Small organisms, such as benthic invertebrates (aquatic insects, worms, etc.) absorb selenium in their tissues.
   • Fish eat many insects and thereby accumulate selenium in their own body.
2. As females lay eggs, the high selenium concentration in their body results in fish eggs with a high selenium content. 
3. High selenium concentration in fish eggs interferes with fish development, and effects have been reported at relatively low water selenium concentrations of 5-10 µg/L in laboratory tests (Lemly, 2002). Hatching time, developmental rate, hatchling survival, and hatchling deformities are some of the effects present in waters with increased selenium concentrations.

Symptoms of selenium toxicity in fish

• Swelling/Inflammation of gills
• Spinal Deformities
• Edema (swelling due to fluid buildup)
• Deformations of the mouth and jaw
• Pathological alterations of livers, kidneys, hearts, and ovaries
• Eye deformations (including cataracts and protruding eyes)
• Reproductive disruption including lack of fertilization, lower hatchability, and higher mortalities of eggs and young fish
• Anemia

Ultimately, yes, if selenium concentrations don’t decrease. Water from the Elk River flows into Lake Koocanusa, and from there it continues to the Kootenay and Columbia Rivers. If not curbed, selenium pollution from the Elk River will continue to contribute to bioaccumulation in Lake Koocanusa and may affect fish further downstream.

Currently, the Lake Koocanusa selenium concentration is about 1 µg/L, which is lower than BC and the United States Environmental Protection Agency limits (2 µg/L and 1.5 µg/L, respectively), but higher than the 0.8 µg/L limit set by the State of Montana in 2020. While the Montana water quality standard is highly cautious—moderate exceedance of this standard is unlikely to have adverse effects on fish—it is a standard that must be met and reinforces the need to curb selenium sources from metallurgical coal mining.

Active Water treatment is an approach to selenium mitigation. Elk Valley Resources (EVR) has active water treatment plants at their Line Creek and Fording River South locations.

EVR is also using a method called “saturated rock fill” (SRF). Saturated rock fills are constructed in mine pits and are kept filled (saturated) with selenium-rich water gathered and pumped from other areas in the mine.  Being covered with water keeps the rock-filled area low in oxygen, which is conducive to the growth of bacteria that convert selenium and nitrogen to less mobile forms. Additional nutrients are added to the rock fill to “boost” the activity of these microbes. The Elkview Saturated Rock Fill has been operational since 2018.

Teck reported that its treatment facilities are achieving about 95% removal of selenium as well as nitrate from treated water. Total water volumes treated by both active treatment and saturated rock fill facilities are have been reported to be 46.5 million gallons per day.

Reductions in selenium concentrations elsewhere in the Elk River system (e.g., Fording River) are not yet apparent according to information provided by the Elk Valley Monitoring Committee (see water quality poster Figure 5); however these data pre-date the commissioning of the Fording River South treatment plant. Given the large volume of legacy waste rock piles at the mining operations, it is not surprising that the relatively recent commissioning of treatment facilities has not yet produced a substantial, or consistent, reduction in selenium concentrations.   

What more can be done?

The key to evaluating the success of mitigation strategies is rigorous monitoring of water quality and assessment of mitigation strategies in a collaborative and transparent manner. Unfortunately, much of the uncertainty over the concentrations and effects of selenium on Elk River stem from insufficient monitoring and lack of data sharing. In 2022 the Elk River Alliance released a discussion document on Proposed Approach for Coal Mining Effluent Regulation [link]. In it we provide several recommendations for improvements to mining effluent management: