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Navajo Aquifer Concerns May Prove True

An article about aquifer depletion due to strip mining on the Black Mesa in Arizona
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For years, Native opponents of a massive strip mine on Black Mesa in northern Arizona have said longstanding extractive practices of Peabody Energy Corp. (formerly Peabody Western Coal Co.) have depleted a major aquifer on which they depend and a recent analysis seems to bear them out.

“The mining-related impacts on the aquifer are more significant than have been recognized or acknowledged,” said Dr. Daniel Higgins, who performed the analysis as part of Arid Lands Resource Studies, graduate interdisciplinary programs, University of Arizona, Tucson.

His findings were hailed by several Hopi and Navajo organizations, including Black Mesa Water Coalition, Dine’ CARE (Citizens Against Ruining Our Environment), and To’Nizhoni Ani (“Beautiful Water Speaks”), as well as the Center for Biological Diversity and Sierra Club.

The report “comes at a critical time while OSM (Office of Surface Mining Reclamation and Enforcement) is preparing an environmental assessment to analyze the impacts of the Kayenta Mine,” Nicole Horseherder of To’ Nizhoni Ani said in a prepared statement. “OSM officials now need to address and respond to this report before they let Peabody off the hook for damage to the Navajo aquifer (N-Aquifer).”

The organizations have submitted the study to OSM for review in connection with a delayed permit that would have allowed Peabody to expand its area of operations on some 100 square miles of Hopi and Navajo lands including Kayenta Mine, which supplies coal via an 83-mile rail line to the Navajo Generating Station near Page, Arizona.

“Despite what these models predicted years ago, I think any reasonable person who looks at the data would conclude that the rates of water level decline at Kayenta and spring discharge decline at Moenkopi are directly related to Peabody’s groundwater withdrawals,” Higgins is quoted as saying in the organizations’ press release.

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The aquifer Higgins studied for more than five years provides drinking water to Native communities and is a source of water below Black Mesa that feeds sacred springs. Opponents object to the further industrial use of the pristine aquifer water.

Peabody’s prediction of probable hydrologic consequences of mining expansion on Black Mesa was based on an “extraordinary range of hydrogeological uncertainties” that “undermines the conclusiveness of its determination of mining-related impacts,” according to Higgins’ analysis.

“There’s more that’s unknown about the aquifer than is known,” he said by telephone. “Is there potential for things to get worse? That potential is there, though I’m not concluding it will happen.”
People customarily think, “Well, the recharge is more than we’re taking from the aquifer every year,” he summarized. “Based on that, we’d replenish what we take out.” But it’s not like a bank account, he explained,“because being able to see any change or reversal (in aquifer depletion) is going to take a tremendous amount of time in a large aquifer. The impacts will get worse before they get better—it’s not like flipping a switch.”

A federal geochemical analysis in 1997 determined that 90 percent of the water in the N-Aquifer is 10,000 to 35,000 years old. “Technically, that 90 percent of the water is not replenishable on a human time-scale but only on a geological time-scale,” he said.

Al Klein, director of OSM’s Western Region said of the N-Aquifer that “the data does not show that we damaged it in any way, that there was any material damage to the N-Aquifer.” His office conducted the environmental studies for Peabody’s expanded permit request, which it administers.

However, “depletion is a different story (than damage). When we do permitting, we do NEPA (National Environmental Policy Act compliance),” he said by telephone, adding he couldn’t comment further because “I need to have perspective on what we’re talking about here.”

Wahleah Johns of the Black Mesa Water Coalition said, “OSM should not award Peabody a permit renewal until a thorough investigation is conducted on the findings of this report on the N-aquifer.”
The revised permit would expand the boundary of the overall mining area by about 19,000 acres. The Department of the Interior vacated a life-of-mine permit OSM issued in late 2008 for mine expansion on Black Mesa and said further compliance with the NEPA would be required, citing significant changes in planning that would affect impacts on several resources, including water supplies.