‘Something’s Really Happening Here’: Mining Is Contaminating Snow in the Northern Rockies

During the winter, storms furniture the Rocky Mountains with snowfall that supplies the Western United States’ communities with h2o during the summer. But snowfall isn’t the lone happening that storms deposit connected those mountains.

A squad of researchers has revealed that the wintertime storms that screen the Rocky Mountains with snowfall besides transportation contaminants from mines. Their work, elaborate successful a study published March 26 successful the diary Environmental Pollution, sheds airy connected the ecological consequences of mining activities and however biology processes circulate metallic pollutants.

Led by Monica Arienzo, a researcher successful the Desert Research Institute’s Division of Hydrologic Sciences, the squad investigated contamination levels of mercury, cadmium, zinc, and antimony successful snowfall crossed the Rocky Mountains.

“Metal contamination successful the Rockies is comparatively understudied,” Arienzo said successful a Desert Research Institute statement. “Other studies person focused connected definite parts, truthful the information that we person this transect from Montana to New Mexico makes this survey unique.”

In the outpouring of 2018, Arienzo and her colleagues collected snowfall samples from 48 locations and analyzed the attraction of metals successful each. To find the magnitude of metallic contaminants originating exclusively from quality activity, they compared the quantity of metallic contaminants originating successful earthy particulate (e.g., calcium) to the quantity of metals from some particulate and quality activity.

Their investigation yet revealed higher concentrations of metallic contaminants from quality enactment successful the snowfall of the bluish Rocky Mountains than successful the confederate Rockies, including successful Montana, Idaho, and Northern Wyoming. The researchers noted, however, that the levels are inactive wrong the U.S. Environmental Protection Agency’s information guidelines for drinking h2o and aquatic life.

To double-check their results, the researchers compared their findings to the National Atmospheric Deposition Program’s information documenting calcium and mercury successful rainfall from 2009 to 2018—and reached the aforesaid conclusion.

Researchers collecting snowfall samples successful 2018. © Desert Research Institute

“I was amazed by the magnitude of statement we saw betwixt each these antithetic information sets we brought together,” Arienzo explained. “The snowfall samples showed america that contamination is higher successful the bluish Rockies, and that was truly interesting. Looking astatine mercury contamination implicit clip helped america accidental that 2018 is not conscionable a fluke. When you commencement to spot these trends that are accordant betwixt antithetic records, it makes you consciousness much assured that something’s truly happening here.”

The researchers reconstructed the question of snowstorms successful 2018 to observe that galore of the ones successful the bluish Rockies had travel from the Pacific Northwest, whereas the ones successful the confederate Rockies came from the Mojave Desert. As a result, they suggest the higher levels of metallic contaminants from snowfall successful the bluish Rockies travel from mines successful the Pacific Northwest, Idaho, and Montana.

“Our thought is that the particulate from existent and humanities mining sites gets carried up into the mountains [by storms] and deposited crossed our survey sites,” Arienzo said. “This survey shows the value of continued technological monitoring efforts,” she concluded, “as good arsenic mitigation of existent and humanities mining sites.”

Even successful the seemingly pristine snowfall of the Rocky Mountains, humans person near their fingerprints.