Scientific Report Urges Steps to Keep Salmon Habitat Safe From BC Mining Boom

A female Chinook Salmon running the rapids in a shallow river. File photo by Eiko Jones.

A collaborative report by 23 science and policy experts published in the peer-reviewed journal Science Advances says the mining industry is falling short of ensuring the health of wild salmon rivers in Western North America and British Columbia and threatening the future of wild salmon population.

“The paper makes it clear that we need to improve risk assessments that take into account extreme climate events and cumulative effects, and that some places may be best as no-go zones for mining,” said Nikki Skuce, a co-author of the paper who serves as co-chair of the BC Mining Law Reform network.

Science Advances, a multidisciplinary open-access scientific journal established in early 2015, is the first open-access journal published by the American Association for the Advancement of Science.

The report reviews relevant aspects of mining operations, describes the ecology of salmonid-bearing watersheds in northwestern North America and compiles the impacts of metal and coal extractions on salmonids and their habitat. Despite impact assessments that are intended to evaluate risk and inform mitigation, mines continue to harm salmonid-bearing watersheds via pathways such as toxic contaminants, stream channel burial, and flow regime alternation, the report said.

The report speaks to the uncertainty in predicting mining impacts, including infrastructure such as water treatment facilities, tailings reservoir liners and water control structures, and concludes that despite the consideration of mitigation measures in modern impact assessment processes, mining continues to harm watersheds.

“There is evidence that the water quality values predicted during the impact assessment process and the mitigations needed to properly treat water are overly optimistic and often fail …,” and forma studies on this are exceedingly rare, the report said.

The authors also note that climate change and associated natural hazards intensify environmental risks and pose direct challenges to the performance of mining infrastructure and mitigation technology. They further conclude that it is impossible to predict with certainty whether water storage and treatment infrastructure will be able to withstand the unknown envelope of environmental variability and unforeseen extreme weather events and earthquakes over two centuries.

The authors recommend that working groups across all levels of affected governments be formed to consolidate basic mining information into publicly available, user-friendly, and annually updated data portals that transcend political boundaries.

Before consideration of a new mining operation begins, all potentially affected jurisdictions should agree to consistent protocols that lead to a collaborative, watershed-scale monitoring and evaluation program, they said.

The envisioned final reporting products would guide monitoring program design, including defined roles and responsibilities, identification of reference sites, sufficient sampling frequency, and a high likelihood to detect changes to the environment due to potential mining impacts, they said.

The complete report is online at https://www.science.org/doi/10.1126/sciadv.abn0929.