Tanya J Gallegos, Ph.D.

Dr. Tanya Gallegos is a research engineer at the U.S. Geological survey and a registered professional engineer in New Mexico. She joined USGS in 2007 as a Mendenhall Post-Doctoral fellow to study the redox chemistry of iron sulfide, arsenic and uranium in uranium mine waters. Her current research encompasses field and lab studies to understand the products, byproducts and wastes from the energy resource life cycles – unconventional oil and shale gas recovery via hydraulic fracturing and uranium recovery via mining and milling. Research topics include: geochemical and isotopic characterization of mine influenced water, oilfield brine, ore, and solid surfaces (gamma spectrometry, SEM, XRD, ICP-OES, ICP-MS EXAFS/XAS); geochemical modeling; integrated assessments for energy resource development; assessing water use in hydraulic fracturing and uranium mining; groundwater restoration at ISR uranium mines; dilute inorganic chemistry; groundwater remediation of trace elements; and naturally occurring radioactive materials (NORM). She is currently managing the Naturally Occurring Radionuclide Lab and the Advancements in Geochemistry and Geomicrobiology of Energy Resources project. She leads three tasks: Developing sensing Methods to Identify Abandoned Mines, Waste as a Resource in Abandoned Mines, and NORM Products in Energy Resource Life Cycles. Tanya also serves on the steering committees for the Federal Remediation Technology Roundtable and the Federal Mining Dialogue and has previously served on the New Mexico Uranium Mining Task Force. She is also an associate editor for Applied Geochemistry. From 2010-2012, she served on the USGS Strategic Science Planning Team for the Energy and Minerals Resource Mission Area.

Work Experience

Research and Applied Engineering Expertise

• Geochemical and isotopic interpretation of unconventional oil and gas produced waters
• Water use in oil and gas production using hydraulic fracturing in the United States
• Water use and groundwater contamination following uranium mining
• Spectroscopic study of nanoscale iron sulfide and uranium reaction products
• Gamma ray spectroscopy for evaluation of naturally occurring radioactive materials (NORM)
• Development of geoenvironmental assessment methodology for uranium mining
• Rock-water-oil interactions during hydraulic fracturing of tight oil plays
• Laboratory studies to understand the redox behavior of iron sulfides, uranium and arsenic
• Geochemical controls on uranium following in-situ uranium recovery (ISR)
• Geochemical and isotopic tracers of elements from uranium mining and hydraulic fracturing
• Characteristics of uranium deposits amenable to situ recovery of uranium in WY and TX
• Civil engineering design of water, wastewater, and drainage systems.