eNews June 2020

NMSU Student Receives NM WRRI Student Water Research Grant to Study the Potential of Clay Pellets to Treat Uranium Contamination in Drinking Water

By Marcus Gay, NM WRRI Student Program Coordinator

During the Cold War, uranium mining occurred throughout northwestern New Mexico and across the Navajo Nation. When demand for uranium declined, the mines were abandoned, and lack of regulations and negligence resulted in abandoned uranium mines with large amounts of radioactive waste throughout the Navajo Nation. These unremediated mines have caused uranium contamination in drinking water in northwestern New Mexico and the Navajo Nation.

Treating the contaminated water and providing access to clean drinking water on the Navajo Nation is challenging. Systems like reverse osmosis are impractical due to energy demands, complexities of the system, and costs. Current methods for providing clean drinking water access, include piping and trucking in water, have proven to be ineffective and many people are often forced to consume heavily contaminated water. Thus, for a solution to be effective at solving this issue, it needs to be simple, inexpensive, and accessible.

Solving this problem is the focus of Moticha Franklin’s research. In June 2019, Franklin was awarded an NM WRRI Student Water Research Grant entitled, Surface Area of a Local Clay Material to Elucidate Uranium Abatement for Potable New Mexico Water Management.

Franklin, who grew up on the Navajo Reservation in Toadlena, New Mexico, is now a student at New Mexico State University in the Department of Chemistry and Biochemistry. Her research explores how clay material can be used to treat contaminated drinking water.

Due to clay’s cation exchange capability, it can bind and sequester heavy metals in water. Clay is difficult to manage in its muddy state, so a fabrication process has been developed at the Alumino Phyllosilicates Research Group laboratory to produce clay ceramic pellets that do not disintegrate in water. This project aims to enhance our understanding of clay sorption in the various states: powder, pellet, porous pellet. Franklin’s team hypothesize that clay powder transformed to pellet form decreases available surface area. The capacity for clays to sorb heavy metals is directly related to the surface area of the clay sorbent, so the degree of surface area abatement is important. A surface area and porosity probe will identify the best sorbent material.

Franklin explains that those who will benefit the most from this research are, “definitely the people in the northwestern region of New Mexico . . . Even though our main target is people in the Navajo Nation and the Pojoaque Basin, the potential of clay pellets is geographically limitless.” According to Franklin, this novel technology can be implemented in individual houses with any water source, regardless of the impurities. Due to its proximity to the affected region, a clay from Gallup, New Mexico, was chosen for this research and Franklin explains that clays can be obtained easily and locally.

In addition to uranium, preliminary tests have provided sorption results for other heavy metals like lead and cadmium. For all pollutants tested, the resulting pollutant levels are well below the EPA standards for safe drinking water.

Franklin presented her research at the 64th Annual New Mexico Water Conference, and plans to present this research at the 57th Clay Mineral Society Meeting in Richland, Washington.

Franklin says this research has connected her to her community in a huge way. “On the Navajo Nation, we deal with a lot of problems that no one can help with. With this research, it can help alleviate one of the major problems the Navajo Nation deals with.” Franklin plans to graduate in spring 2021 with a Bachelor of Science in Chemistry, and plans to either continue her education or teach.