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MSU study to examine possible links between abandoned mines, Crow water

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BOZEMAN, Mont. – A Montana State University graduate student who grew up hunting agates along the Little Bighorn River now plans to study abandoned mines to see if they’re contaminating water on the Crow Indian Reservation.

Anita Moore-Nall of Bozeman said she will use her 2010 Dennis and Phyllis Washington Native American Graduate Fellowship to examine old uranium and vanadium mines in southern Montana and northern Wyoming.

The $10,000 fellowship will allow her to collect rock samples from abandoned mines in the Pryor Mountains of Montana and possibly in the Little Sheep Mountain Anticline in Wyoming, said Moore-Nall, a master’s degree student in earth sciences, geology consultant, and enrolled member of the Crow Tribe. She will also collect rock, mud and water samples from the Kane Cave area in northern Wyoming, hire undergraduate and graduate student assistants, and pay for sample analysis.

Mari Eggers, a doctoral candidate at MSU and research associate with Little Big Horn College, said Moore-Nall’s research will not only address new questions in geology, but it will be valuable in understanding water quality issues in the Bighorn River Valley on the Crow Reservation. The lower part of the river, downstream of Hardin, is on the State of Montana’s “303d” list of impaired water bodies due to relatively high levels of lead and mercury contamination.

“Walleye in Bighorn Lake, upriver of this impaired stretch, have some of the highest mercury levels of all fish tested by the EPA in a nationwide study,” Eggers said. “The sources and distribution of this lead and mercury contamination are currently unknown.”

Moore-Nall’s research will explore the mineralization of uranium deposits in the Pryor Mountains and their relationship to the hydrothermal Kane Cave area in Wyoming to see if these may provide a geological source for those contaminants. Some of the minerals included in the uranium ore and gangue (waste) rocks had mercury in them. The cave, which is at river level, contains radioactive mud, Moore-Nall said.

Eggers said this study, in turn, will help determine whether water in the upper Bighorn River valley should be tested for lead, mercury and/or other toxic materials.

“Numerous residents of the valley rely on shallow wells for their drinking water, and the river is the drinking water source for the Town of Hardin, so the research Anita is undertaking will be very valuable to our community,” Eggers said.

Moore-Nall said coal plants could be contributing to water contamination on the reservation, but she suspects that hydrothermal influences may be involved. Possibly the construction of Yellowtail Dam allowed naturally occurring hydrothermal waters entering the river through faults to be less diluted by changing the flow of the river and allowing mercury and lead to accumulate.

Hydrothermal refers to warm to hot water. Hydrothermal fluids often rise along faults through the upper parts of the Earth’s crust. This may be occurring in the Little Sheep Mountain Anticline, where caves contain radioactive mud and warm water, Moore-Nall said. The level of the river water sometimes reaches the level of the caves.

If there were a connected fault system during the mineralization of the mines in the Pryor Mountain area, the hydrothermal fluids could have carried uranium, lead and mercury into these deposits, Moore-Nall said. She added that the hydrothermal activity may not be present in the mine area now, but the deposits may reflect past hydrothermal activity. Her study will help see if there is a link in the present-day hydrothermal activity of the cave area and the mobilization of uranium, lead and mercury present in the mines.

David Lageson, a geology professor and Moore-Nall’s academic adviser, said the hypothesis is credible and worth investigating. He noted that the mine-water quality relationship is just one aspect of Moore-Nall’s thesis. She is looking at a combination of problems in the Pryor Mountains that deal with structural geology and the mineralization of uranium ore deposits.

Eggers said Moore-Nall recently discussed her research interests with the Crow Environmental Health Steering Committee, the community group that guides the ongoing water quality research on the reservation.

“Her work clearly complements our existing research project, which primarily focuses on the Little Bighorn River valley and well water quality reservation-wide,” Eggers said.

The CEHSC represents Little Big Horn College, the Apsaalooke Water and Wastewater Authority, the Indian Health Service Hospital, the Crow Tribe and the 107 Committee of Tribal Elders. Technical expertise in water quality and hydrology are provided by Anne Camper and members of her lab, Water Quality Extension Agent Adam Sigler, and Brian McGlynn, all at MSU. Other collaborators include Montana staff of the U.S. Geological Survey, the Environmental Protection Agency and the U.S. Fish and Wildlife Service.

Moore-Nall said she has long been interested in rocks, mining and the outdoors. Her father’s family had a placer claim near Sheridan, Mont. Her father, Paul H. Moore, was an engineer with the BIA, so she spent much of her youth on the Blackfoot Indian Reservation near Glacier National Park. As a result, she became fascinated by geology and mountains, Moore-Nall said. During family fishing trips to area streams, she panned for gold and collected garnets and agates. During trips to visit her mother Rosa’s family on the Crow Indian Reservation, she hunted for agates.

“It’s just nice to be outside and work outside,” Moore-Nall said. “How amazing it is that you can look at rocks and think of them being changed and folded and broken up. And mountains – I like mountains a lot.”

Moore-Nall, now 50, graduated from MSU in 1984 with a bachelor’s degree in geology and photography. She then worked with the USGS and later as an engineering technician at Mineral Hill at Jardine. She later returned to Bozeman and worked as an engineering technician for the U.S. Forest Service. She continues to work as a consulting geologist for exploration companies, including World Industrial Minerals out of Colorado.

Along the way, Moore-Nall became a competitive runner and Nordic skier, and an artist who specializes in beadwork and watercolor. She and her husband, Randy, have two children. Since Randy, a fly fishing guide with the winters off, has a passion for surfing the family used to camp in Baja, Calif. for two or three months every winter.

“I’m not traditional for a Native American or a non-Native American,” Moore-Nall said.

In January, Moore-Nall returned to MSU, where she is part of Lageson’s structure research group in the Department of Earth Sciences. The group – housed in the newly remodeled Gaines Hall – consists of graduate students who work on various projects dealing with structural geology and tectonics in the northern Rockies.

Moore-Nall learned in July that she had been awarded the Native American Graduate Fellowship. The Dennis and Phyllis Washington Foundation awards two Native American Graduate Fellowships a year – one to an MSU grad student and one to a University of Montana grad student. The fellowships run a maximum of two years for master’s students and three years for doctoral students.

“We are thrilled that she received that,” Lageson said. “She was an outstanding undergraduate in our department years ago. We are very excited that she is working again in the department as a graduate student. She brings a lot of experience and knowledge to the table in terms of her work in graduate geology.”