Arizona officials have voted to allow a uranium mine near Grand Canyon National Park to raise the allowable levels of arsenic in a monitoring well, despite opposition from the Havasupai Tribal Council.
The Pinyon Plain Mine is located seven miles south of Grand Canyon National Park and sits atop the Redwall-Muav aquifer, which is the sole water source for the local Havasupai people and the source of Havasu Creek, a tributary of the Grand Canyon.
Environmental groups and the Havasupai Tribe say the decision could have large ramifications for the Grand Canyon National Park and beyond, as arsenic could contaminate the aquifer and permanently pollute the canyon’s natural springs.
Amber Reimondo, energy director for the nonprofit Grand Canyon Trust, said that the original maximum allowed level of arsenic was already five times the drinking water standard set by the Environmental Protection Agency (EPA).
The EPA sets the arsenic standard for drinking water at ten micrograms per liter due to its potential to cause several types of cancer.
According to the Arizona Department of Environmental Quality (ADEQ), the decision does not allow the introduction of pollution or a weakening of safeguards, but rather reflects the natural geological reality of the area.
Caroline Oppleman, ADEQ spokesperson, said that over four-and-a-half years of rigorous, site-specific data confirm that the mine is not adding arsenic to the groundwater, but rather, the physical structure of the mineshaft has created a hydraulic sink that draws existing, naturally-occurring geological arsenic from the surrounding area toward the perimeter wells.
Related: Tennis vs Badminton 6 Differences That You Should Know About
Reimondo argued that shifting the arsenic limits in the mine’s monitoring well introduces a dangerous variable into a fragile ecosystem, and that if arsenic seeps into the deep groundwater pathways, it could reach the aquifer and permanently pollute the canyon’s natural springs.
Hydrology in the Grand Canyon is complex.
Making it difficult to determine where water runs and the extent of potential contamination, according to Reimondo, mining in the region has the potential to cause contamination to the springs both inside the Grand Canyon and the groundwater.
The Havasupai Tribal Council chairwoman Melinda Yaiva opposed the decision.
Environmental groups like the Grand Canyon Trust say the decision could have large ramifications for the Grand Canyon National Park and beyond.
The mine, which was built in the eighties, spans 17 acres, and runs nearly 1,500 feet deep.
They are concerned about the potential impact on outdoor escapes in the area.
